[Ocfs2-tools-devel] [PATCH 03/10] libocfs2: Move b-tree function to extent_tree.c.
Tao Ma
tao.ma at oracle.com
Wed Sep 30 07:27:40 PDT 2009
Now b-tree functions are all in libocfs2/extend_file.c.
But since Tiger has added a new file named extent_tree.c,
We'd better move all b-tree related functions there.
Note:
I only cut/paste the code here, and no functions are changed.
Signed-off-by: Tao Ma <tao.ma at oracle.com>
---
libocfs2/extend_file.c | 3728 -----------------------------------------------
libocfs2/extent_tree.c | 3731 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 3731 insertions(+), 3728 deletions(-)
diff --git a/libocfs2/extend_file.c b/libocfs2/extend_file.c
index 65d3133..d12cb9f 100644
--- a/libocfs2/extend_file.c
+++ b/libocfs2/extend_file.c
@@ -35,3734 +35,6 @@
#include <assert.h>
#include "ocfs2/ocfs2.h"
-/*
- * Structures which describe a path through a btree, and functions to
- * manipulate them.
- *
- * The idea here is to be as generic as possible with the tree
- * manipulation code.
- */
-struct ocfs2_path_item {
- uint64_t blkno;
- char *buf;
- struct ocfs2_extent_list *el;
-};
-
-#define OCFS2_MAX_PATH_DEPTH 5
-
-struct ocfs2_path {
- int p_tree_depth;
- struct ocfs2_path_item p_node[OCFS2_MAX_PATH_DEPTH];
-};
-
-#define path_root_blkno(_path) ((_path)->p_node[0].blkno)
-#define path_root_buf(_path) ((_path)->p_node[0].buf)
-#define path_root_el(_path) ((_path)->p_node[0].el)
-#define path_leaf_blkno(_path) ((_path)->p_node[(_path)->p_tree_depth].blkno)
-#define path_leaf_buf(_path) ((_path)->p_node[(_path)->p_tree_depth].buf)
-#define path_leaf_el(_path) ((_path)->p_node[(_path)->p_tree_depth].el)
-#define path_num_items(_path) ((_path)->p_tree_depth + 1)
-
-struct insert_ctxt {
- ocfs2_filesys *fs;
- struct ocfs2_dinode *di;
- struct ocfs2_extent_rec rec;
-};
-/*
- * Reset the actual path elements so that we can re-use the structure
- * to build another path. Generally, this involves freeing the buffer
- * heads.
- */
-static void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root)
-{
- int i, start = 0, depth = 0;
- struct ocfs2_path_item *node;
-
- if (keep_root)
- start = 1;
-
- for(i = start; i < path_num_items(path); i++) {
- node = &path->p_node[i];
- if (!node->buf)
- continue;
-
- ocfs2_free(&node->buf);
- node->blkno = 0;
- node->buf = NULL;
- node->el = NULL;
- }
-
- /*
- * Tree depth may change during truncate, or insert. If we're
- * keeping the root extent list, then make sure that our path
- * structure reflects the proper depth.
- */
- if (keep_root)
- depth = path_root_el(path)->l_tree_depth;
-
- path->p_tree_depth = depth;
-}
-
-static void ocfs2_free_path(struct ocfs2_path *path)
-{
- /* We don't free the root because often in libocfs2 the root is a
- * shared buffer such as the inode. Caller must be responsible for
- * handling the root of the path.
- */
- if (path) {
- ocfs2_reinit_path(path, 1);
- ocfs2_free(&path);
- }
-}
-
-/*
- * All the elements of src into dest. After this call, src could be freed
- * without affecting dest.
- *
- * Both paths should have the same root. Any non-root elements of dest
- * will be freed.
- */
-static void ocfs2_cp_path(ocfs2_filesys *fs,
- struct ocfs2_path *dest,
- struct ocfs2_path *src)
-{
- int i;
- struct ocfs2_extent_block *eb = NULL;
-
- assert(path_root_blkno(dest) == path_root_blkno(src));
- dest->p_tree_depth = src->p_tree_depth;
-
- for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
- if (!src->p_node[i].buf) {
- if (dest->p_node[i].buf)
- ocfs2_free(dest->p_node[i].buf);
- dest->p_node[i].blkno = 0;
- dest->p_node[i].buf = NULL;
- dest->p_node[i].el = NULL;
- continue;
- }
-
- if (!dest->p_node[i].buf)
- ocfs2_malloc_block(fs->fs_io, &dest->p_node[i].buf);
-
- assert(dest->p_node[i].buf);
- memcpy(dest->p_node[i].buf, src->p_node[i].buf,
- fs->fs_blocksize);
- eb = (struct ocfs2_extent_block *)dest->p_node[i].buf;
- dest->p_node[i].el = &eb->h_list;
-
- dest->p_node[i].blkno = src->p_node[i].blkno;
- }
-}
-
-/*
- * Make the *dest path the same as src and re-initialize src path to
- * have a root only.
- */
-static void ocfs2_mv_path(struct ocfs2_path *dest, struct ocfs2_path *src)
-{
- int i;
-
- assert(path_root_blkno(dest) == path_root_blkno(src));
-
- for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
- ocfs2_free(&dest->p_node[i].buf);
-
- dest->p_node[i].blkno = src->p_node[i].blkno;
- dest->p_node[i].buf = src->p_node[i].buf;
- dest->p_node[i].el = src->p_node[i].el;
-
- src->p_node[i].blkno = 0;
- src->p_node[i].buf = NULL;
- src->p_node[i].el = NULL;
- }
-}
-
-/*
- * Insert an extent block at given index.
- *
- * Note:
- * This buf will be inserted into the path, so the caller shouldn't free it.
- */
-static inline void ocfs2_path_insert_eb(struct ocfs2_path *path, int index,
- char *buf)
-{
- struct ocfs2_extent_block *eb = (struct ocfs2_extent_block *) buf;
- /*
- * Right now, no root buf is an extent block, so this helps
- * catch code errors with dinode trees. The assertion can be
- * safely removed if we ever need to insert extent block
- * structures at the root.
- */
- assert(index);
-
- path->p_node[index].blkno = eb->h_blkno;
- path->p_node[index].buf = (char *)buf;
- path->p_node[index].el = &eb->h_list;
-}
-
-static struct ocfs2_path *ocfs2_new_path(ocfs2_filesys* fs, char *buf,
- struct ocfs2_extent_list *root_el)
-{
- errcode_t ret = 0;
- struct ocfs2_path *path = NULL;
- struct ocfs2_dinode *di = (struct ocfs2_dinode *)buf;
-
- assert(root_el->l_tree_depth < OCFS2_MAX_PATH_DEPTH);
-
- ret = ocfs2_malloc0(sizeof(*path), &path);
- if (path) {
- path->p_tree_depth = root_el->l_tree_depth;
- path->p_node[0].blkno = di->i_blkno;
- path->p_node[0].buf = buf;
- path->p_node[0].el = root_el;
- }
-
- return path;
-}
-
-/*
- * Allocate and initialize a new path based on a disk inode tree.
- */
-static struct ocfs2_path *ocfs2_new_inode_path(ocfs2_filesys *fs,
- struct ocfs2_dinode *di)
-{
- struct ocfs2_extent_list *el = &di->id2.i_list;
-
- return ocfs2_new_path(fs, (char *)di, el);
-}
-
-/* Write all the extent block information to the disk.
- * We write all paths furthur down than subtree_index.
- * The caller will handle writing the sub_index.
- */
-static errcode_t ocfs2_write_path_eb(ocfs2_filesys *fs,
- struct ocfs2_path *path, int sub_index)
-{
- errcode_t ret;
- int i;
-
- for (i = path->p_tree_depth; i > sub_index; i--) {
- ret = ocfs2_write_extent_block(fs,
- path->p_node[i].blkno,
- path->p_node[i].buf);
- if (ret)
- return ret;
- }
-
- return 0;
-}
-
-/* some extent blocks is modified and we need to synchronize them to the disk
- * accordingly.
- *
- * We will not update the inode if subtree_index is "0" since it should be
- * updated by the caller.
- *
- * left_path or right_path can be NULL, but they can't be NULL in the same time.
- * And if they are both not NULL, we will treat subtree_index in the right_path
- * as the right extent block information.
- */
-static errcode_t ocfs2_sync_path_to_disk(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- int subtree_index)
-{
- errcode_t ret = 0;
- struct ocfs2_path *path = NULL;
-
- assert(left_path || right_path);
- if (left_path) {
- ret = ocfs2_write_path_eb(fs, left_path, subtree_index);
- if (ret)
- goto bail;
- }
-
- if (right_path) {
- ret = ocfs2_write_path_eb(fs, right_path, subtree_index);
- if (ret)
- goto bail;
- }
-
- if (subtree_index) {
- /* subtree_index indicates an extent block. */
- path = right_path ? right_path : left_path;
-
- ret = ocfs2_write_extent_block(fs,
- path->p_node[subtree_index].blkno,
- path->p_node[subtree_index].buf);
- if (ret)
- goto bail;
- }
-bail:
- return ret;
-}
-
-/*
- * Return the index of the extent record which contains cluster #v_cluster.
- * -1 is returned if it was not found.
- *
- * Should work fine on interior and exterior nodes.
- */
-int ocfs2_search_extent_list(struct ocfs2_extent_list *el, uint32_t v_cluster)
-{
- int ret = -1;
- int i;
- struct ocfs2_extent_rec *rec;
- uint32_t rec_end, rec_start, clusters;
-
- for(i = 0; i < el->l_next_free_rec; i++) {
- rec = &el->l_recs[i];
-
- rec_start = rec->e_cpos;
- clusters = ocfs2_rec_clusters(el->l_tree_depth, rec);
-
- rec_end = rec_start + clusters;
-
- if (v_cluster >= rec_start && v_cluster < rec_end) {
- ret = i;
- break;
- }
- }
-
- return ret;
-}
-
-enum ocfs2_contig_type {
- CONTIG_NONE = 0,
- CONTIG_LEFT,
- CONTIG_RIGHT,
- CONTIG_LEFTRIGHT,
-};
-
-/*
- * NOTE: ocfs2_block_extent_contig(), ocfs2_extents_adjacent() and
- * ocfs2_extent_contig only work properly against leaf nodes!
- */
-static inline int ocfs2_block_extent_contig(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *ext,
- uint64_t blkno)
-{
- uint64_t blk_end = ext->e_blkno;
-
- blk_end += ocfs2_clusters_to_blocks(fs, ext->e_leaf_clusters);
-
- return blkno == blk_end;
-}
-
-static inline int ocfs2_extents_adjacent(struct ocfs2_extent_rec *left,
- struct ocfs2_extent_rec *right)
-{
- uint32_t left_range;
-
- left_range = left->e_cpos + left->e_leaf_clusters;
-
- return (left_range == right->e_cpos);
-}
-
-static enum ocfs2_contig_type
- ocfs2_extent_contig(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *ext,
- struct ocfs2_extent_rec *insert_rec)
-{
- uint64_t blkno = insert_rec->e_blkno;
-
- /*
- * Refuse to coalesce extent records with different flag
- * fields - we don't want to mix unwritten extents with user
- * data.
- */
- if (ext->e_flags != insert_rec->e_flags)
- return CONTIG_NONE;
-
- if (ocfs2_extents_adjacent(ext, insert_rec) &&
- ocfs2_block_extent_contig(fs, ext, blkno))
- return CONTIG_RIGHT;
-
- blkno = ext->e_blkno;
- if (ocfs2_extents_adjacent(insert_rec, ext) &&
- ocfs2_block_extent_contig(fs, insert_rec, blkno))
- return CONTIG_LEFT;
-
- return CONTIG_NONE;
-}
-
-/*
- * NOTE: We can have pretty much any combination of contiguousness and
- * appending.
- *
- * The usefulness of APPEND_TAIL is more in that it lets us know that
- * we'll have to update the path to that leaf.
- */
-enum ocfs2_append_type {
- APPEND_NONE = 0,
- APPEND_TAIL,
-};
-
-enum ocfs2_split_type {
- SPLIT_NONE = 0,
- SPLIT_LEFT,
- SPLIT_RIGHT,
-};
-
-struct ocfs2_insert_type {
- enum ocfs2_split_type ins_split;
- enum ocfs2_append_type ins_appending;
- enum ocfs2_contig_type ins_contig;
- int ins_contig_index;
- int ins_tree_depth;
-};
-
-struct ocfs2_merge_ctxt {
- enum ocfs2_contig_type c_contig_type;
- int c_has_empty_extent;
- int c_split_covers_rec;
-};
-
-/*
- * Helper function for ocfs2_add_branch() and shift_tree_depth().
- *
- * Returns the sum of the rightmost extent rec logical offset and
- * cluster count.
- *
- * ocfs2_add_branch() uses this to determine what logical cluster
- * value should be populated into the leftmost new branch records.
- *
- * shift_tree_depth() uses this to determine the # clusters
- * value for the new topmost tree record.
- */
-static inline uint32_t ocfs2_sum_rightmost_rec(struct ocfs2_extent_list *el)
-{
- uint16_t i = el->l_next_free_rec - 1;
-
- return el->l_recs[i].e_cpos +
- ocfs2_rec_clusters(el->l_tree_depth, &el->l_recs[i]);
-
-}
-
-/*
- * Add an entire tree branch to our inode. eb_buf is the extent block
- * to start at, if we don't want to start the branch at the dinode
- * structure.
- *
- * last_eb_buf is required as we have to update it's next_leaf pointer
- * for the new last extent block.
- *
- * the new branch will be 'empty' in the sense that every block will
- * contain a single record with e_clusters == 0.
- */
-static int ocfs2_add_branch(ocfs2_filesys *fs,
- struct ocfs2_dinode *fe,
- char *eb_buf,
- char **last_eb_buf)
-{
- errcode_t ret;
- int new_blocks, i;
- uint64_t next_blkno, new_last_eb_blk;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *eb_el;
- struct ocfs2_extent_list *el;
- uint32_t new_cpos;
- uint64_t *new_blknos = NULL;
- char **new_eb_bufs = NULL;
- char *buf = NULL;
-
- assert(*last_eb_buf);
-
- if (eb_buf) {
- eb = (struct ocfs2_extent_block *) eb_buf;
- el = &eb->h_list;
- } else
- el = &fe->id2.i_list;
-
- /* we never add a branch to a leaf. */
- assert(el->l_tree_depth);
-
- new_blocks = el->l_tree_depth;
-
- /* allocate the number of new eb blocks we need new_blocks should be
- * allocated here.*/
- ret = ocfs2_malloc0(sizeof(uint64_t) * new_blocks, &new_blknos);
- if (ret)
- goto bail;
- memset(new_blknos, 0, sizeof(uint64_t) * new_blocks);
-
- ret = ocfs2_malloc0(sizeof(char *) * new_blocks, &new_eb_bufs);
- if (ret)
- goto bail;
- memset(new_eb_bufs, 0, sizeof(char *) * new_blocks);
-
- for (i = 0; i < new_blocks; i++) {
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- return ret;
- new_eb_bufs[i] = buf;
-
- ret = ocfs2_new_extent_block(fs, &new_blknos[i]);
- if (ret)
- goto bail;
-
- ret = ocfs2_read_extent_block(fs, new_blknos[i], buf);
- if (ret)
- goto bail;
- }
-
- eb = (struct ocfs2_extent_block *)(*last_eb_buf);
- new_cpos = ocfs2_sum_rightmost_rec(&eb->h_list);
-
- /* Note: new_eb_bufs[new_blocks - 1] is the guy which will be
- * linked with the rest of the tree.
- * conversly, new_eb_bufs[0] is the new bottommost leaf.
- *
- * when we leave the loop, new_last_eb_blk will point to the
- * newest leaf, and next_blkno will point to the topmost extent
- * block.
- */
- next_blkno = new_last_eb_blk = 0;
- for(i = 0; i < new_blocks; i++) {
- buf = new_eb_bufs[i];
- eb = (struct ocfs2_extent_block *) buf;
- eb_el = &eb->h_list;
-
- eb->h_next_leaf_blk = 0;
- eb_el->l_tree_depth = i;
- eb_el->l_next_free_rec = 1;
- memset(eb_el->l_recs, 0,
- sizeof(struct ocfs2_extent_rec) * eb_el->l_count);
- /*
- * This actually counts as an empty extent as
- * c_clusters == 0
- */
- eb_el->l_recs[0].e_cpos = new_cpos;
- eb_el->l_recs[0].e_blkno = next_blkno;
- /*
- * eb_el isn't always an interior node, but even leaf
- * nodes want a zero'd flags and reserved field so
- * this gets the whole 32 bits regardless of use.
- */
- eb_el->l_recs[0].e_int_clusters = 0;
-
- if (!eb_el->l_tree_depth)
- new_last_eb_blk = eb->h_blkno;
-
- next_blkno = eb->h_blkno;
- }
-
- /* Link the new branch into the rest of the tree (el will
- * either be on the fe, or the extent block passed in.
- */
- i = el->l_next_free_rec;
- el->l_recs[i].e_blkno = next_blkno;
- el->l_recs[i].e_cpos = new_cpos;
- el->l_recs[i].e_int_clusters = 0;
- el->l_next_free_rec++;
-
- /* fe needs a new last extent block pointer, as does the
- * next_leaf on the previously last-extent-block.
- */
- fe->i_last_eb_blk = new_last_eb_blk;
-
- /* here all the extent block and the new inode information should be
- * written back to the disk.
- */
- for(i = 0; i < new_blocks; i++) {
- buf = new_eb_bufs[i];
- ret = ocfs2_write_extent_block(fs, new_blknos[i], buf);
- if (ret)
- goto bail;
- }
-
- /* update last_eb_buf's next_leaf pointer for
- * the new last extent block.
- */
- eb = (struct ocfs2_extent_block *)(*last_eb_buf);
- eb->h_next_leaf_blk = new_last_eb_blk;
- ret = ocfs2_write_extent_block(fs, eb->h_blkno, *last_eb_buf);
- if (ret)
- goto bail;
-
- if (eb_buf) {
- eb = (struct ocfs2_extent_block *)eb_buf;
- ret = ocfs2_write_extent_block(fs, eb->h_blkno, eb_buf);
- if (ret)
- goto bail;
- }
-
- /*
- * Some callers want to track the rightmost leaf so pass it
- * back here.
- */
- memcpy(*last_eb_buf, new_eb_bufs[0], fs->fs_blocksize);
-
- /* The inode information isn't updated since we use duplicated extent
- * block in the insertion and it may fail in other steps.
- */
- ret = 0;
-bail:
- if (new_eb_bufs) {
- for (i = 0; i < new_blocks; i++)
- if (new_eb_bufs[i])
- ocfs2_free(&new_eb_bufs[i]);
- ocfs2_free(&new_eb_bufs);
- }
-
- if (ret && new_blknos)
- for (i = 0; i < new_blocks; i++)
- if (new_blknos[i])
- ocfs2_delete_extent_block(fs, new_blknos[i]);
-
- if (new_blknos)
- ocfs2_free(&new_blknos);
-
- return ret;
-}
-
-/*
- * Should only be called when there is no space left in any of the
- * leaf nodes. What we want to do is find the lowest tree depth
- * non-leaf extent block with room for new records. There are three
- * valid results of this search:
- *
- * 1) a lowest extent block is found, then we pass it back in
- * *target_buf and return '0'
- *
- * 2) the search fails to find anything, but the dinode has room. We
- * pass NULL back in *target_buf, but still return '0'
- *
- * 3) the search fails to find anything AND the dinode is full, in
- * which case we return > 0
- *
- * return status < 0 indicates an error.
- */
-static errcode_t ocfs2_find_branch_target(ocfs2_filesys *fs,
- struct ocfs2_dinode *fe,
- char **target_buf)
-{
- errcode_t ret = 0;
- int i;
- uint64_t blkno;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
- char *buf = NULL, *lowest_buf = NULL;
-
- *target_buf = NULL;
-
- el = &fe->id2.i_list;
-
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- return ret;
-
- while(el->l_tree_depth > 1) {
- if (el->l_next_free_rec == 0) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto bail;
- }
- i = el->l_next_free_rec - 1;
- blkno = el->l_recs[i].e_blkno;
- if (!blkno) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto bail;
- }
-
- ret = ocfs2_read_extent_block(fs, blkno, buf);
- if (ret)
- goto bail;
-
- eb = (struct ocfs2_extent_block *) buf;
- el = &eb->h_list;
-
- if (el->l_next_free_rec < el->l_count)
- lowest_buf = buf;
- }
-
- /* If we didn't find one and the fe doesn't have any room,
- * then return '1' */
- if (!lowest_buf
- && (fe->id2.i_list.l_next_free_rec == fe->id2.i_list.l_count))
- ret = 1;
-
- *target_buf = lowest_buf;
-bail:
- if (buf && !*target_buf)
- ocfs2_free(&buf);
-
- return ret;
-}
-
-/*
- * This function will discard the rightmost extent record.
- */
-static void ocfs2_shift_records_right(struct ocfs2_extent_list *el)
-{
- int next_free = el->l_next_free_rec;
- int count = el->l_count;
- unsigned int num_bytes;
-
- assert(next_free);
- /* This will cause us to go off the end of our extent list. */
- assert(next_free < count);
-
- num_bytes = sizeof(struct ocfs2_extent_rec) * next_free;
-
- memmove(&el->l_recs[1], &el->l_recs[0], num_bytes);
-}
-
-static void ocfs2_rotate_leaf(struct ocfs2_extent_list *el,
- struct ocfs2_extent_rec *insert_rec)
-{
- int i, insert_index, next_free, has_empty, num_bytes;
- uint32_t insert_cpos = insert_rec->e_cpos;
- struct ocfs2_extent_rec *rec;
-
- next_free = el->l_next_free_rec;
- has_empty = ocfs2_is_empty_extent(&el->l_recs[0]);
-
- assert(next_free);
-
- /* The tree code before us didn't allow enough room in the leaf. */
- if (el->l_next_free_rec == el->l_count && !has_empty)
- assert(0);
-
- /*
- * The easiest way to approach this is to just remove the
- * empty extent and temporarily decrement next_free.
- */
- if (has_empty) {
- /*
- * If next_free was 1 (only an empty extent), this
- * loop won't execute, which is fine. We still want
- * the decrement above to happen.
- */
- for(i = 0; i < (next_free - 1); i++)
- el->l_recs[i] = el->l_recs[i+1];
-
- next_free--;
- }
-
- /* Figure out what the new record index should be. */
- for(i = 0; i < next_free; i++) {
- rec = &el->l_recs[i];
-
- if (insert_cpos < rec->e_cpos)
- break;
- }
- insert_index = i;
-
- assert(insert_index >= 0);
- assert(insert_index < el->l_count);
- assert(insert_index <= next_free);
-
- /* No need to memmove if we're just adding to the tail. */
- if (insert_index != next_free) {
- assert(next_free < el->l_count);
-
- num_bytes = next_free - insert_index;
- num_bytes *= sizeof(struct ocfs2_extent_rec);
- memmove(&el->l_recs[insert_index + 1],
- &el->l_recs[insert_index],
- num_bytes);
- }
-
- /*
- * Either we had an empty extent, and need to re-increment or
- * there was no empty extent on a non full rightmost leaf node,
- * in which case we still need to increment.
- */
- next_free++;
- el->l_next_free_rec = next_free;
- /* Make sure none of the math above just messed up our tree. */
- assert(el->l_next_free_rec <= el->l_count);
-
- el->l_recs[insert_index] = *insert_rec;
-}
-
-static void ocfs2_remove_empty_extent(struct ocfs2_extent_list *el)
-{
- int size, num_recs = el->l_next_free_rec;
-
- assert(num_recs);
-
- if (ocfs2_is_empty_extent(&el->l_recs[0])) {
- num_recs--;
- size = num_recs * sizeof(struct ocfs2_extent_rec);
- memmove(&el->l_recs[0], &el->l_recs[1], size);
- memset(&el->l_recs[num_recs], 0,
- sizeof(struct ocfs2_extent_rec));
- el->l_next_free_rec = num_recs;
- }
-}
-
-/*
- * Create an empty extent record .
- *
- * l_next_free_rec may be updated.
- *
- * If an empty extent already exists do nothing.
- */
-static void ocfs2_create_empty_extent(struct ocfs2_extent_list *el)
-{
- int next_free = el->l_next_free_rec;
-
- assert(el->l_tree_depth == 0);
-
- if (next_free == 0)
- goto set_and_inc;
-
- if (ocfs2_is_empty_extent(&el->l_recs[0]))
- return;
-
- ocfs2_shift_records_right(el);
-
-set_and_inc:
- el->l_next_free_rec += 1;
- memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
-}
-
-/*
- * For a rotation which involves two leaf nodes, the "root node" is
- * the lowest level tree node which contains a path to both leafs. This
- * resulting set of information can be used to form a complete "subtree"
- *
- * This function is passed two full paths from the dinode down to a
- * pair of adjacent leaves. It's task is to figure out which path
- * index contains the subtree root - this can be the root index itself
- * in a worst-case rotation.
- *
- * The array index of the subtree root is passed back.
- */
-static int ocfs2_find_subtree_root(struct ocfs2_path *left,
- struct ocfs2_path *right)
-{
- int i = 0;
-
- /* Check that the caller passed in two paths from the same tree. */
- assert(path_root_blkno(left) == path_root_blkno(right));
-
- do {
- i++;
-
- /* The caller didn't pass two adjacent paths. */
- if (i > left->p_tree_depth)
- assert(0);
- } while (left->p_node[i].blkno == right->p_node[i].blkno);
-
- return i - 1;
-}
-
-typedef errcode_t (path_insert_t)(void *, char *);
-
-/*
- * Traverse a btree path in search of cpos, starting at root_el.
- *
- * This code can be called with a cpos larger than the tree, in which
- * case it will return the rightmost path.
- */
-static errcode_t __ocfs2_find_path(ocfs2_filesys *fs,
- struct ocfs2_extent_list *root_el,
- uint32_t cpos,
- path_insert_t *func,
- void *data)
-{
- int i, ret = 0;
- uint32_t range;
- uint64_t blkno;
- char *buf = NULL;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
- struct ocfs2_extent_rec *rec;
-
- el = root_el;
- while (el->l_tree_depth) {
- if (el->l_next_free_rec == 0) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
-
- }
-
-
- for(i = 0; i < el->l_next_free_rec - 1; i++) {
- rec = &el->l_recs[i];
-
- /*
- * In the case that cpos is off the allocation
- * tree, this should just wind up returning the
- * rightmost record.
- */
- range = rec->e_cpos +
- ocfs2_rec_clusters(el->l_tree_depth, rec);
- if (cpos >= rec->e_cpos && cpos < range)
- break;
- }
-
- blkno = el->l_recs[i].e_blkno;
- if (blkno == 0) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
- }
-
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- return ret;
-
- ret = ocfs2_read_extent_block(fs, blkno, buf);
- if (ret)
- goto out;
-
- eb = (struct ocfs2_extent_block *) buf;
- el = &eb->h_list;
-
- if (el->l_next_free_rec > el->l_count) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
- }
-
- /* The user's callback must give us the tip for how to
- * handle the buf we allocated by return values.
- *
- * 1) return '0':
- * the function succeeds,and it will use the buf and
- * take care of the buffer release.
- *
- * 2) return > 0:
- * the function succeeds, and there is no need for buf,
- * so we will release it.
- *
- * 3) return < 0:
- * the function fails.
- */
- if (func) {
- ret = func(data, buf);
-
- if (ret == 0) {
- buf = NULL;
- continue;
- }
- else if (ret < 0)
- goto out;
- }
- ocfs2_free(&buf);
- buf = NULL;
- }
-
-out:
- /* Catch any trailing buf that the loop didn't handle. */
- if (buf)
- ocfs2_free(&buf);
-
- return ret;
-}
-
-/*
- * Given an initialized path (that is, it has a valid root extent
- * list), this function will traverse the btree in search of the path
- * which would contain cpos.
- *
- * The path traveled is recorded in the path structure.
- *
- * Note that this will not do any comparisons on leaf node extent
- * records, so it will work fine in the case that we just added a tree
- * branch.
- */
-struct find_path_data {
- int index;
- struct ocfs2_path *path;
-};
-
-static errcode_t find_path_ins(void *data, char *eb)
-{
- struct find_path_data *fp = data;
-
- ocfs2_path_insert_eb(fp->path, fp->index, eb);
- fp->index++;
-
- return 0;
-}
-
-static int ocfs2_find_path(ocfs2_filesys *fs, struct ocfs2_path *path,
- uint32_t cpos)
-{
- struct find_path_data data;
-
- data.index = 1;
- data.path = path;
- return __ocfs2_find_path(fs, path_root_el(path), cpos,
- find_path_ins, &data);
-}
-
-/*
- * Find the leaf block in the tree which would contain cpos. No
- * checking of the actual leaf is done.
- *
- * This function doesn't handle non btree extent lists.
- */
-int ocfs2_find_leaf(ocfs2_filesys *fs, struct ocfs2_dinode *di,
- uint32_t cpos, char **leaf_buf)
-{
- int ret;
- char *buf = NULL;
- struct ocfs2_path *path = NULL;
- struct ocfs2_extent_list *el = &di->id2.i_list;
-
- assert(el->l_tree_depth > 0);
-
- path = ocfs2_new_inode_path(fs, di);
- if (!path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- ret = ocfs2_find_path(fs, path, cpos);
- if (ret)
- goto out;
-
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- goto out;
-
- memcpy(buf, path_leaf_buf(path), fs->fs_blocksize);
- *leaf_buf = buf;
-out:
- ocfs2_free_path(path);
- return ret;
-}
-
-int ocfs2_xattr_find_leaf(ocfs2_filesys *fs, struct ocfs2_xattr_block *xb,
- uint32_t cpos, char **leaf_buf)
-{
- int ret;
- char *buf = NULL;
- struct ocfs2_path *path = NULL;
- struct ocfs2_extent_list *el = &xb->xb_attrs.xb_root.xt_list;
-
- assert(el->l_tree_depth > 0);
-
-
- ret = ocfs2_malloc0(sizeof(*path), &path);
-
- if (!path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- } else {
- path->p_tree_depth = el->l_tree_depth;
- path->p_node[0].blkno = xb->xb_blkno;
- path->p_node[0].buf = (char *)xb;
- path->p_node[0].el = el;
- }
-
- ret = ocfs2_find_path(fs, path, cpos);
- if (ret)
- goto out;
-
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- goto out;
-
- memcpy(buf, path_leaf_buf(path), fs->fs_blocksize);
- *leaf_buf = buf;
-out:
- ocfs2_free_path(path);
- return ret;
-}
-
-/*
- * Adjust the adjacent records (left_rec, right_rec) involved in a rotation.
- *
- * Basically, we've moved stuff around at the bottom of the tree and
- * we need to fix up the extent records above the changes to reflect
- * the new changes.
- *
- * left_rec: the record on the left.
- * left_child_el: is the child list pointed to by left_rec
- * right_rec: the record to the right of left_rec
- * right_child_el: is the child list pointed to by right_rec
- *
- * By definition, this only works on interior nodes.
- */
-static void ocfs2_adjust_adjacent_records(struct ocfs2_extent_rec *left_rec,
- struct ocfs2_extent_list *left_child_el,
- struct ocfs2_extent_rec *right_rec,
- struct ocfs2_extent_list *right_child_el)
-{
- uint32_t left_clusters, right_end;
-
- /*
- * Interior nodes never have holes. Their cpos is the cpos of
- * the leftmost record in their child list. Their cluster
- * count covers the full theoretical range of their child list
- * - the range between their cpos and the cpos of the record
- * immediately to their right.
- */
- left_clusters = right_child_el->l_recs[0].e_cpos;
- if (ocfs2_is_empty_extent(&right_child_el->l_recs[0])) {
- assert(right_child_el->l_next_free_rec > 1);
- left_clusters = right_child_el->l_recs[1].e_cpos;
- }
- left_clusters -= left_rec->e_cpos;
- left_rec->e_int_clusters = left_clusters;
-
- /*
- * Calculate the rightmost cluster count boundary before
- * moving cpos - we will need to adjust clusters after
- * updating e_cpos to keep the same highest cluster count.
- */
- right_end = right_rec->e_cpos;
- right_end += right_rec->e_int_clusters;
-
- right_rec->e_cpos = left_rec->e_cpos;
- right_rec->e_cpos += left_clusters;
-
- right_end -= right_rec->e_cpos;
- right_rec->e_int_clusters = right_end;
-}
-
-/*
- * Adjust the adjacent root node records involved in a
- * rotation. left_el_blkno is passed in as a key so that we can easily
- * find it's index in the root list.
- */
-static void ocfs2_adjust_root_records(struct ocfs2_extent_list *root_el,
- struct ocfs2_extent_list *left_el,
- struct ocfs2_extent_list *right_el,
- uint64_t left_el_blkno)
-{
- int i;
-
- assert(root_el->l_tree_depth > left_el->l_tree_depth);
-
- for(i = 0; i < root_el->l_next_free_rec - 1; i++) {
- if (root_el->l_recs[i].e_blkno == left_el_blkno)
- break;
- }
-
- /*
- * The path walking code should have never returned a root and
- * two paths which are not adjacent.
- */
- assert(i < (root_el->l_next_free_rec - 1));
-
- ocfs2_adjust_adjacent_records(&root_el->l_recs[i], left_el,
- &root_el->l_recs[i + 1], right_el);
-}
-
-/*
- * We've changed a leaf block (in right_path) and need to reflect that
- * change back up the subtree.
- *
- * This happens in multiple places:
- * - When we've moved an extent record from the left path leaf to the right
- * path leaf to make room for an empty extent in the left path leaf.
- * - When our insert into the right path leaf is at the leftmost edge
- * and requires an update of the path immediately to it's left. This
- * can occur at the end of some types of rotation and appending inserts.
- */
-static void ocfs2_complete_edge_insert(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- int subtree_index)
-{
- int i, idx;
- uint64_t blkno;
- struct ocfs2_extent_list *el, *left_el, *right_el;
- struct ocfs2_extent_rec *left_rec, *right_rec;
-
- /*
- * Update the counts and position values within all the
- * interior nodes to reflect the leaf rotation we just did.
- *
- * The root node is handled below the loop.
- *
- * We begin the loop with right_el and left_el pointing to the
- * leaf lists and work our way up.
- *
- * NOTE: within this loop, left_el and right_el always refer
- * to the *child* lists.
- */
- left_el = path_leaf_el(left_path);
- right_el = path_leaf_el(right_path);
- for(i = left_path->p_tree_depth - 1; i > subtree_index; i--) {
-
- /*
- * One nice property of knowing that all of these
- * nodes are below the root is that we only deal with
- * the leftmost right node record and the rightmost
- * left node record.
- */
- el = left_path->p_node[i].el;
- idx = left_el->l_next_free_rec - 1;
- left_rec = &el->l_recs[idx];
-
- el = right_path->p_node[i].el;
- right_rec = &el->l_recs[0];
-
- ocfs2_adjust_adjacent_records(left_rec, left_el, right_rec,
- right_el);
-
- /*
- * Setup our list pointers now so that the current
- * parents become children in the next iteration.
- */
- left_el = left_path->p_node[i].el;
- right_el = right_path->p_node[i].el;
- }
-
- /*
- * At the root node, adjust the two adjacent records which
- * begin our path to the leaves.
- */
-
- el = left_path->p_node[subtree_index].el;
- left_el = left_path->p_node[subtree_index + 1].el;
- right_el = right_path->p_node[subtree_index + 1].el;
- blkno = left_path->p_node[subtree_index + 1].blkno;
-
- ocfs2_adjust_root_records(el, left_el, right_el, blkno);
-
- /* ocfs2_adjust_root_records only update the extent block in the left
- * path, and actually right_path->p_node[subtree_index].eb indicates the
- * same extent block, so we must keep them the same content.
- */
- memcpy(right_path->p_node[subtree_index].buf,
- left_path->p_node[subtree_index].buf, fs->fs_blocksize);
-}
-
-/* Rotate the subtree to right.
- *
- * Note: After successful rotation, the extent block will be flashed
- * to disk accordingly.
- */
-static errcode_t ocfs2_rotate_subtree_right(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- int subtree_index)
-{
- errcode_t ret;
- int i;
- char *right_leaf_eb;
- char *left_leaf_eb = NULL;
- struct ocfs2_extent_list *right_el, *left_el;
- struct ocfs2_extent_rec move_rec;
- struct ocfs2_extent_block *eb;
-
- left_leaf_eb = path_leaf_buf(left_path);
- eb = (struct ocfs2_extent_block *)left_leaf_eb;
- left_el = path_leaf_el(left_path);
-
- if (left_el->l_next_free_rec != left_el->l_count)
- return OCFS2_ET_CORRUPT_EXTENT_BLOCK;
-
- /*
- * This extent block may already have an empty record, so we
- * return early if so.
- */
- if (ocfs2_is_empty_extent(&left_el->l_recs[0]))
- return 0;
-
- assert(left_path->p_node[subtree_index].blkno ==
- right_path->p_node[subtree_index].blkno);
-
- right_leaf_eb = path_leaf_buf(right_path);
- right_el = path_leaf_el(right_path);
-
- ocfs2_create_empty_extent(right_el);
-
- /* Do the copy now. */
- i = left_el->l_next_free_rec - 1;
- move_rec = left_el->l_recs[i];
- right_el->l_recs[0] = move_rec;
-
- /*
- * Clear out the record we just copied and shift everything
- * over, leaving an empty extent in the left leaf.
- *
- * We temporarily subtract from next_free_rec so that the
- * shift will lose the tail record (which is now defunct).
- */
- left_el->l_next_free_rec -= 1;
- ocfs2_shift_records_right(left_el);
- memset(&left_el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
- left_el->l_next_free_rec += 1;
-
- ocfs2_complete_edge_insert(fs, left_path, right_path, subtree_index);
-
- ret = ocfs2_sync_path_to_disk(fs, left_path, right_path, subtree_index);
-
- return ret;
-}
-
-/*
- * Given a full path, determine what cpos value would return us a path
- * containing the leaf immediately to the left of the current one.
- *
- * Will return zero if the path passed in is already the leftmost path.
- */
-static int ocfs2_find_cpos_for_left_leaf(struct ocfs2_path *path,
- uint32_t *cpos)
-{
- int i, j, ret = 0;
- uint64_t blkno;
- struct ocfs2_extent_list *el;
-
- assert(path->p_tree_depth > 0);
-
- *cpos = 0;
-
- blkno = path_leaf_blkno(path);
-
- /* Start at the tree node just above the leaf and work our way up. */
- i = path->p_tree_depth - 1;
- while (i >= 0) {
- el = path->p_node[i].el;
-
- /* Find the extent record just before the one in our path. */
- for(j = 0; j < el->l_next_free_rec; j++) {
- if (el->l_recs[j].e_blkno == blkno) {
- if (j == 0) {
- if (i == 0) {
- /*
- * We've determined that the
- * path specified is already
- * the leftmost one - return a
- * cpos of zero.
- */
- goto out;
- }
- /*
- * The leftmost record points to our
- * leaf - we need to travel up the
- * tree one level.
- */
- goto next_node;
- }
-
- *cpos = el->l_recs[j - 1].e_cpos;
- *cpos = *cpos + ocfs2_rec_clusters(
- el->l_tree_depth,
- &el->l_recs[j - 1]);
- *cpos = *cpos - 1;
- goto out;
- }
- }
-
- /*
- * If we got here, we never found a valid node where
- * the tree indicated one should be.
- */
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
-
-next_node:
- blkno = path->p_node[i].blkno;
- i--;
- }
-
-out:
- return ret;
-}
-
-/*
- * Trap the case where we're inserting into the theoretical range past
- * the _actual_ left leaf range. Otherwise, we'll rotate a record
- * whose cpos is less than ours into the right leaf.
- *
- * It's only necessary to look at the rightmost record of the left
- * leaf because the logic that calls us should ensure that the
- * theoretical ranges in the path components above the leaves are
- * correct.
- */
-static int ocfs2_rotate_requires_path_adjustment(struct ocfs2_path *left_path,
- uint32_t insert_cpos)
-{
- struct ocfs2_extent_list *left_el;
- struct ocfs2_extent_rec *rec;
- int next_free;
-
- left_el = path_leaf_el(left_path);
- next_free = left_el->l_next_free_rec;
- rec = &left_el->l_recs[next_free - 1];
-
- if (insert_cpos > rec->e_cpos)
- return 1;
- return 0;
-}
-
-static int ocfs2_leftmost_rec_contains(struct ocfs2_extent_list *el,
- uint32_t cpos)
-{
- int next_free = el->l_next_free_rec;
- unsigned int range;
- struct ocfs2_extent_rec *rec;
-
- if (next_free == 0)
- return 0;
-
- rec = &el->l_recs[0];
- if (ocfs2_is_empty_extent(rec)) {
- /* Empty list. */
- if (next_free == 1)
- return 0;
- rec = &el->l_recs[1];
- }
-
- range = rec->e_cpos + ocfs2_rec_clusters(el->l_tree_depth, rec);
- if (cpos >= rec->e_cpos && cpos < range)
- return 1;
- return 0;
-}
-
-/*
- * Rotate all the records in a btree right one record, starting at insert_cpos.
- *
- * The path to the rightmost leaf should be passed in.
- *
- * The array is assumed to be large enough to hold an entire path (tree depth).
- *
- * Upon succesful return from this function:
- *
- * - The 'right_path' array will contain a path to the leaf block
- * whose range contains e_cpos.
- * - That leaf block will have a single empty extent in list index 0.
- * - In the case that the rotation requires a post-insert update,
- * *ret_left_path will contain a valid path which can be passed to
- * ocfs2_insert_path().
- */
-static int ocfs2_rotate_tree_right(ocfs2_filesys *fs,
- enum ocfs2_split_type split,
- uint32_t insert_cpos,
- struct ocfs2_path *right_path,
- struct ocfs2_path **ret_left_path)
-{
- int ret, start;
- uint32_t cpos;
- struct ocfs2_path *left_path = NULL;
-
- *ret_left_path = NULL;
-
- left_path = ocfs2_new_path(fs, path_root_buf(right_path),
- path_root_el(right_path));
- if (!left_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- ret = ocfs2_find_cpos_for_left_leaf(right_path, &cpos);
- if (ret)
- goto out;
-
- /*
- * What we want to do here is:
- *
- * 1) Start with the rightmost path.
- *
- * 2) Determine a path to the leaf block directly to the left
- * of that leaf.
- *
- * 3) Determine the 'subtree root' - the lowest level tree node
- * which contains a path to both leaves.
- *
- * 4) Rotate the subtree.
- *
- * 5) Find the next subtree by considering the left path to be
- * the new right path.
- *
- * The check at the top of this while loop also accepts
- * insert_cpos == cpos because cpos is only a _theoretical_
- * value to get us the left path - insert_cpos might very well
- * be filling that hole.
- *
- * Stop at a cpos of '0' because we either started at the
- * leftmost branch (i.e., a tree with one branch and a
- * rotation inside of it), or we've gone as far as we can in
- * rotating subtrees.
- */
- while (cpos && insert_cpos <= cpos) {
-
- ret = ocfs2_find_path(fs, left_path, cpos);
- if (ret)
- goto out;
-
- if (path_leaf_blkno(left_path) == path_leaf_blkno(right_path))
- assert(0);
-
- if (split == SPLIT_NONE &&
- ocfs2_rotate_requires_path_adjustment(left_path,
- insert_cpos)) {
- /*
- * We've rotated the tree as much as we
- * should. The rest is up to
- * ocfs2_insert_path() to complete, after the
- * record insertion. We indicate this
- * situation by returning the left path.
- *
- * The reason we don't adjust the records here
- * before the record insert is that an error
- * later might break the rule where a parent
- * record e_cpos will reflect the actual
- * e_cpos of the 1st nonempty record of the
- * child list.
- */
- *ret_left_path = left_path;
- goto out_ret_path;
- }
-
- start = ocfs2_find_subtree_root(left_path, right_path);
-
- ret = ocfs2_rotate_subtree_right(fs, left_path, right_path,
- start);
- if (ret)
- goto out;
-
- if (split != SPLIT_NONE &&
- ocfs2_leftmost_rec_contains(path_leaf_el(right_path),
- insert_cpos)) {
- /*
- * A rotate moves the rightmost left leaf
- * record over to the leftmost right leaf
- * slot. If we're doing an extent split
- * instead of a real insert, then we have to
- * check that the extent to be split wasn't
- * just moved over. If it was, then we can
- * exit here, passing left_path back -
- * ocfs2_split_extent() is smart enough to
- * search both leaves.
- */
- *ret_left_path = left_path;
- goto out_ret_path;
- }
- /*
- * There is no need to re-read the next right path
- * as we know that it'll be our current left
- * path. Optimize by copying values instead.
- */
- ocfs2_mv_path(right_path, left_path);
-
- ret = ocfs2_find_cpos_for_left_leaf(right_path, &cpos);
- if (ret)
- goto out;
- }
-
-out:
- ocfs2_free_path(left_path);
-
-out_ret_path:
- return ret;
-}
-
-static void ocfs2_update_edge_lengths(struct ocfs2_path *path)
-{
- int i, idx;
- struct ocfs2_extent_rec *rec;
- struct ocfs2_extent_list *el;
- struct ocfs2_extent_block *eb;
- uint32_t range;
-
- /* Path should always be rightmost. */
- eb = (struct ocfs2_extent_block *)path_leaf_buf(path);
- assert(eb->h_next_leaf_blk == 0ULL);
-
- el = &eb->h_list;
- assert(el->l_next_free_rec > 0);
- idx = el->l_next_free_rec - 1;
- rec = &el->l_recs[idx];
- range = rec->e_cpos + ocfs2_rec_clusters(el->l_tree_depth, rec);
-
- for (i = 0; i < path->p_tree_depth; i++) {
- el = path->p_node[i].el;
- idx = el->l_next_free_rec - 1;
- rec = &el->l_recs[idx];
-
- rec->e_int_clusters = range;
- rec->e_int_clusters -= rec->e_cpos;
- }
-}
-
-static errcode_t ocfs2_unlink_path(ocfs2_filesys *fs,
- struct ocfs2_path *path, int unlink_start)
-{
- int ret, i;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
- char *buf;
-
- for(i = unlink_start; i < path_num_items(path); i++) {
- buf = path->p_node[i].buf;
-
- eb = (struct ocfs2_extent_block *)buf;
- /*
- * Not all nodes might have had their final count
- * decremented by the caller - handle this here.
- */
- el = &eb->h_list;
- assert(el->l_next_free_rec <= 1);
-
- el->l_next_free_rec = 0;
- memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
- ret = ocfs2_delete_extent_block(fs, path->p_node[i].blkno);
- if (ret)
- return ret;
- }
- return 0;
-}
-
-/*
- * ocfs2_unlink_subtree will delete extent blocks in the "right_path"
- * from "subtree_index".
- */
-static errcode_t ocfs2_unlink_subtree(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- int subtree_index)
-{
- errcode_t ret;
- int i;
- struct ocfs2_extent_list *root_el = left_path->p_node[subtree_index].el;
- struct ocfs2_extent_list *el;
- struct ocfs2_extent_block *eb;
-
- el = path_leaf_el(left_path);
-
- eb = (struct ocfs2_extent_block *)right_path->p_node[subtree_index + 1].buf;
-
- for(i = 1; i < root_el->l_next_free_rec; i++)
- if (root_el->l_recs[i].e_blkno == eb->h_blkno)
- break;
-
- assert(i < root_el->l_next_free_rec);
-
- memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
- root_el->l_next_free_rec -= 1;
-
- eb = (struct ocfs2_extent_block *)path_leaf_buf(left_path);
- eb->h_next_leaf_blk = 0;
-
- ret = ocfs2_unlink_path(fs, right_path, subtree_index + 1);
- if (ret)
- return ret;
-
- return 0;
-}
-
-static int ocfs2_rotate_subtree_left(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- int subtree_index,
- int *deleted)
-{
- errcode_t ret;
- int i, del_right_subtree = 0, right_has_empty = 0;
- char *root_buf, *di_buf = path_root_buf(right_path);
- struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_buf;
- struct ocfs2_extent_list *right_leaf_el, *left_leaf_el;
- struct ocfs2_extent_block *eb;
-
- *deleted = 0;
-
- right_leaf_el = path_leaf_el(right_path);
- left_leaf_el = path_leaf_el(left_path);
- root_buf = left_path->p_node[subtree_index].buf;
- assert(left_path->p_node[subtree_index].blkno ==
- right_path->p_node[subtree_index].blkno);
-
- if (!ocfs2_is_empty_extent(&left_leaf_el->l_recs[0]))
- return 0;
-
- eb = (struct ocfs2_extent_block *)path_leaf_buf(right_path);
- if (ocfs2_is_empty_extent(&right_leaf_el->l_recs[0])) {
- /*
- * It's legal for us to proceed if the right leaf is
- * the rightmost one and it has an empty extent. There
- * are two cases to handle - whether the leaf will be
- * empty after removal or not. If the leaf isn't empty
- * then just remove the empty extent up front. The
- * next block will handle empty leaves by flagging
- * them for unlink.
- *
- * Non rightmost leaves will throw EAGAIN and the
- * caller can manually move the subtree and retry.
- */
-
- if (eb->h_next_leaf_blk != 0ULL)
- return EAGAIN;
-
- if (right_leaf_el->l_next_free_rec > 1) {
- ocfs2_remove_empty_extent(right_leaf_el);
- } else
- right_has_empty = 1;
- }
-
- if (eb->h_next_leaf_blk == 0ULL &&
- right_leaf_el->l_next_free_rec == 1) {
- /*
- * We have to update i_last_eb_blk during the meta
- * data delete.
- */
- del_right_subtree = 1;
- }
-
- /*
- * Getting here with an empty extent in the right path implies
- * that it's the rightmost path and will be deleted.
- */
- assert(!right_has_empty || del_right_subtree);
-
- if (!right_has_empty) {
- /*
- * Only do this if we're moving a real
- * record. Otherwise, the action is delayed until
- * after removal of the right path in which case we
- * can do a simple shift to remove the empty extent.
- */
- ocfs2_rotate_leaf(left_leaf_el, &right_leaf_el->l_recs[0]);
- memset(&right_leaf_el->l_recs[0], 0,
- sizeof(struct ocfs2_extent_rec));
- }
- if (eb->h_next_leaf_blk == 0ULL) {
- /*
- * Move recs over to get rid of empty extent, decrease
- * next_free. This is allowed to remove the last
- * extent in our leaf (setting l_next_free_rec to
- * zero) - the delete code below won't care.
- */
- ocfs2_remove_empty_extent(right_leaf_el);
- }
-
- if (del_right_subtree) {
- ocfs2_unlink_subtree(fs, left_path, right_path, subtree_index);
- ocfs2_update_edge_lengths(left_path);
-
- /*
- * Now the good extent block information is stored in left_path, so
- * synchronize the right path with it.
- */
- for (i = 0; i <= subtree_index; i++)
- memcpy(right_path->p_node[i].buf,
- left_path->p_node[i].buf,
- fs->fs_blocksize);
-
- eb = (struct ocfs2_extent_block *)path_leaf_buf(left_path);
- di->i_last_eb_blk = eb->h_blkno;
-
- /*
- * Removal of the extent in the left leaf was skipped
- * above so we could delete the right path
- * 1st.
- */
- if (right_has_empty)
- ocfs2_remove_empty_extent(left_leaf_el);
-
- *deleted = 1;
-
- /*
- * The extent block in the right path belwo subtree_index
- * have been deleted, so we don't need to synchronize
- * them to the disk.
- */
- ret = ocfs2_sync_path_to_disk(fs, left_path, NULL,
- subtree_index);
- } else {
- ocfs2_complete_edge_insert(fs, left_path, right_path,
- subtree_index);
-
- ret = ocfs2_sync_path_to_disk(fs, left_path, right_path,
- subtree_index);
- }
-
- return ret;
-}
-
-/*
- * Given a full path, determine what cpos value would return us a path
- * containing the leaf immediately to the right of the current one.
- *
- * Will return zero if the path passed in is already the rightmost path.
- *
- * This looks similar, but is subtly different to
- * ocfs2_find_cpos_for_left_leaf().
- */
-static int ocfs2_find_cpos_for_right_leaf(ocfs2_filesys *fs,
- struct ocfs2_path *path,
- uint32_t *cpos)
-{
- int i, j, ret = 0;
- uint64_t blkno;
- struct ocfs2_extent_list *el;
-
- *cpos = 0;
-
- if (path->p_tree_depth == 0)
- return 0;
-
- blkno = path_leaf_blkno(path);
-
- /* Start at the tree node just above the leaf and work our way up. */
- i = path->p_tree_depth - 1;
- while (i >= 0) {
- int next_free;
-
- el = path->p_node[i].el;
-
- /*
- * Find the extent record just after the one in our
- * path.
- */
- next_free = el->l_next_free_rec;
- for(j = 0; j < el->l_next_free_rec; j++) {
- if (el->l_recs[j].e_blkno == blkno) {
- if (j == (next_free - 1)) {
- if (i == 0) {
- /*
- * We've determined that the
- * path specified is already
- * the rightmost one - return a
- * cpos of zero.
- */
- goto out;
- }
- /*
- * The rightmost record points to our
- * leaf - we need to travel up the
- * tree one level.
- */
- goto next_node;
- }
-
- *cpos = el->l_recs[j + 1].e_cpos;
- goto out;
- }
- }
-
- /*
- * If we got here, we never found a valid node where
- * the tree indicated one should be.
- */
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
-
-next_node:
- blkno = path->p_node[i].blkno;
- i--;
- }
-
-out:
- return ret;
-}
-
-static void ocfs2_rotate_rightmost_leaf_left(ocfs2_filesys *fs,
- struct ocfs2_extent_list *el)
-{
- if (!ocfs2_is_empty_extent(&el->l_recs[0]))
- return;
-
- ocfs2_remove_empty_extent(el);
-
- return;
-}
-
-static int __ocfs2_rotate_tree_left(ocfs2_filesys *fs,
- struct ocfs2_path *path,
- struct ocfs2_path **empty_extent_path)
-{
- int i, ret, subtree_root, deleted;
- uint32_t right_cpos;
- struct ocfs2_path *left_path = NULL;
- struct ocfs2_path *right_path = NULL;
-
- assert(ocfs2_is_empty_extent(&(path_leaf_el(path)->l_recs[0])));
-
- *empty_extent_path = NULL;
-
- ret = ocfs2_find_cpos_for_right_leaf(fs, path, &right_cpos);
- if (ret)
- goto out;
-
- left_path = ocfs2_new_path(fs, path_root_buf(path),
- path_root_el(path));
- if (!left_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- ocfs2_cp_path(fs, left_path, path);
-
- right_path = ocfs2_new_path(fs, path_root_buf(path),
- path_root_el(path));
- if (!right_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- while (right_cpos) {
- ret = ocfs2_find_path(fs, right_path, right_cpos);
- if (ret)
- goto out;
-
- subtree_root = ocfs2_find_subtree_root(left_path,
- right_path);
-
- ret = ocfs2_rotate_subtree_left(fs, left_path,
- right_path, subtree_root,
- &deleted);
- if (ret == EAGAIN) {
- /*
- * The rotation has to temporarily stop due to
- * the right subtree having an empty
- * extent. Pass it back to the caller for a
- * fixup.
- */
- *empty_extent_path = right_path;
- right_path = NULL;
- goto out;
- }
- if (ret)
- goto out;
-
- /*
- * The subtree rotate might have removed records on
- * the rightmost edge. If so, then rotation is
- * complete.
- */
- if (deleted)
- break;
-
- ocfs2_mv_path(left_path, right_path);
-
- ret = ocfs2_find_cpos_for_right_leaf(fs, left_path,
- &right_cpos);
- if (ret)
- goto out;
- }
-
-out:
- ocfs2_free_path(right_path);
- ocfs2_free_path(left_path);
-
- /*
- * the path's information is changed during the process of rotation,
- * so re-read them.
- */
- for (i = 1; i <= path->p_tree_depth; i++) {
- ret = ocfs2_read_extent_block(fs, path->p_node[i].blkno,
- path->p_node[i].buf);
- if (ret)
- break;
- }
-
- return ret;
-}
-
-static int ocfs2_remove_rightmost_path(ocfs2_filesys *fs,
- struct ocfs2_path *path)
-{
- int ret, subtree_index, i;
- uint32_t cpos;
- struct ocfs2_path *left_path = NULL;
- struct ocfs2_dinode *di;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
-
- /*
- * XXX: This code assumes that the root is an inode, which is
- * true for now but may change as tree code gets generic.
- */
- di = (struct ocfs2_dinode *)path_root_buf(path);
-
- ret = ocfs2_find_cpos_for_left_leaf(path, &cpos);
- if (ret)
- goto out;
-
- if (cpos) {
- /*
- * We have a path to the left of this one - it needs
- * an update too.
- */
- left_path = ocfs2_new_path(fs, path_root_buf(path),
- path_root_el(path));
- if (!left_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- ret = ocfs2_find_path(fs, left_path, cpos);
- if (ret)
- goto out;
-
- subtree_index = ocfs2_find_subtree_root(left_path, path);
-
- ocfs2_unlink_subtree(fs, left_path, path,
- subtree_index);
- ocfs2_update_edge_lengths(left_path);
-
- /*
- * Now the good extent block information is stored in left_path, so
- * synchronize the right path with it.
- */
- for (i = 0; i <= subtree_index; i++)
- memcpy(path->p_node[i].buf,
- left_path->p_node[i].buf,
- fs->fs_blocksize);
- ret = ocfs2_sync_path_to_disk(fs, left_path,
- NULL, subtree_index);
- if (ret)
- goto out;
-
- eb = (struct ocfs2_extent_block *)path_leaf_buf(left_path);
- di->i_last_eb_blk = eb->h_blkno;
- } else {
- /*
- * 'path' is also the leftmost path which
- * means it must be the only one. This gets
- * handled differently because we want to
- * revert the inode back to having extents
- * in-line.
- */
- ocfs2_unlink_path(fs, path, 1);
-
- el = &di->id2.i_list;
- el->l_tree_depth = 0;
- el->l_next_free_rec = 0;
- memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
-
- di->i_last_eb_blk = 0;
- }
-
-out:
- ocfs2_free_path(left_path);
- return ret;
-}
-
-/*
- * Left rotation of btree records.
- *
- * In many ways, this is (unsurprisingly) the opposite of right
- * rotation. We start at some non-rightmost path containing an empty
- * extent in the leaf block. The code works its way to the rightmost
- * path by rotating records to the left in every subtree.
- *
- * This is used by any code which reduces the number of extent records
- * in a leaf. After removal, an empty record should be placed in the
- * leftmost list position.
- *
- * This won't handle a length update of the rightmost path records if
- * the rightmost tree leaf record is removed so the caller is
- * responsible for detecting and correcting that.
- */
-static int ocfs2_rotate_tree_left(ocfs2_filesys *fs, struct ocfs2_path *path)
-{
- int ret = 0;
- struct ocfs2_path *tmp_path = NULL, *restart_path = NULL;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
-
- el = path_leaf_el(path);
- if (!ocfs2_is_empty_extent(&el->l_recs[0]))
- return 0;
-
- if (path->p_tree_depth == 0) {
-rightmost_no_delete:
- /*
- * In-inode extents. This is trivially handled, so do
- * it up front.
- */
- ocfs2_rotate_rightmost_leaf_left(fs,
- path_leaf_el(path));
-
- /* we have to synchronize the modified extent block to disk. */
- if (path->p_tree_depth > 0) {
- ret = ocfs2_write_extent_block(fs,
- path_leaf_blkno(path),
- path_leaf_buf(path));
- }
-
- goto out;
- }
-
- /*
- * Handle rightmost branch now. There's several cases:
- * 1) simple rotation leaving records in there. That's trivial.
- * 2) rotation requiring a branch delete - there's no more
- * records left. Two cases of this:
- * a) There are branches to the left.
- * b) This is also the leftmost (the only) branch.
- *
- * 1) is handled via ocfs2_rotate_rightmost_leaf_left()
- * 2a) we need the left branch so that we can update it with the unlink
- * 2b) we need to bring the inode back to inline extents.
- */
-
- eb = (struct ocfs2_extent_block *)path_leaf_buf(path);
- el = &eb->h_list;
- if (eb->h_next_leaf_blk == 0) {
- /*
- * This gets a bit tricky if we're going to delete the
- * rightmost path. Get the other cases out of the way
- * 1st.
- */
- if (el->l_next_free_rec > 1)
- goto rightmost_no_delete;
-
- if (el->l_next_free_rec == 0) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
- }
-
- /*
- * XXX: The caller can not trust "path" any more after
- * this as it will have been deleted. What do we do?
- *
- * In theory the rotate-for-merge code will never get
- * here because it'll always ask for a rotate in a
- * nonempty list.
- */
-
- ret = ocfs2_remove_rightmost_path(fs, path);
- goto out;
- }
-
- /*
- * Now we can loop, remembering the path we get from EAGAIN
- * and restarting from there.
- */
-try_rotate:
- ret = __ocfs2_rotate_tree_left(fs, path, &restart_path);
- if (ret && ret != EAGAIN) {
- goto out;
- }
-
- while (ret == EAGAIN) {
- tmp_path = restart_path;
- restart_path = NULL;
-
- ret = __ocfs2_rotate_tree_left(fs, tmp_path, &restart_path);
- if (ret && ret != EAGAIN) {
- goto out;
- }
-
- ocfs2_free_path(tmp_path);
- tmp_path = NULL;
-
- if (ret == 0)
- goto try_rotate;
- }
-
-out:
- ocfs2_free_path(tmp_path);
- ocfs2_free_path(restart_path);
- return ret;
-}
-
-static void ocfs2_cleanup_merge(struct ocfs2_extent_list *el,
- int index)
-{
- struct ocfs2_extent_rec *rec = &el->l_recs[index];
- unsigned int size;
-
- if (rec->e_leaf_clusters == 0) {
- /*
- * We consumed all of the merged-from record. An empty
- * extent cannot exist anywhere but the 1st array
- * position, so move things over if the merged-from
- * record doesn't occupy that position.
- *
- * This creates a new empty extent so the caller
- * should be smart enough to have removed any existing
- * ones.
- */
- if (index > 0) {
- assert(!ocfs2_is_empty_extent(&el->l_recs[0]));
- size = index * sizeof(struct ocfs2_extent_rec);
- memmove(&el->l_recs[1], &el->l_recs[0], size);
- }
-
- /*
- * Always memset - the caller doesn't check whether it
- * created an empty extent, so there could be junk in
- * the other fields.
- */
- memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
- }
-}
-
-/*
- * Remove split_rec clusters from the record at index and merge them
- * onto the beginning of the record at index + 1.
- */
-static int ocfs2_merge_rec_right(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *split_rec,
- struct ocfs2_extent_list *el, int index)
-{
- unsigned int split_clusters = split_rec->e_leaf_clusters;
- struct ocfs2_extent_rec *left_rec;
- struct ocfs2_extent_rec *right_rec;
-
- assert(index < el->l_next_free_rec);
-
- left_rec = &el->l_recs[index];
- right_rec = &el->l_recs[index + 1];
-
- left_rec->e_leaf_clusters -= split_clusters;
-
- right_rec->e_cpos -= split_clusters;
- right_rec->e_blkno -=
- ocfs2_clusters_to_blocks(fs, split_clusters);
- right_rec->e_leaf_clusters += split_clusters;
-
- ocfs2_cleanup_merge(el, index);
-
- return 0;
-}
-
-/*
- * Remove split_rec clusters from the record at index and merge them
- * onto the tail of the record at index - 1.
- */
-static int ocfs2_merge_rec_left(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *split_rec,
- struct ocfs2_extent_list *el, int index)
-{
- int has_empty_extent = 0;
- unsigned int split_clusters = split_rec->e_leaf_clusters;
- struct ocfs2_extent_rec *left_rec;
- struct ocfs2_extent_rec *right_rec;
-
- assert(index > 0);
-
- left_rec = &el->l_recs[index - 1];
- right_rec = &el->l_recs[index];
- if (ocfs2_is_empty_extent(&el->l_recs[0]))
- has_empty_extent = 1;
-
- if (has_empty_extent && index == 1) {
- /*
- * The easy case - we can just plop the record right in.
- */
- *left_rec = *split_rec;
-
- has_empty_extent = 0;
- } else {
- left_rec->e_leaf_clusters += split_clusters;
- }
-
- right_rec->e_cpos += split_clusters;
- right_rec->e_blkno +=
- ocfs2_clusters_to_blocks(fs, split_clusters);
- right_rec->e_leaf_clusters -= split_clusters;
-
- ocfs2_cleanup_merge(el, index);
-
- return 0;
-}
-
-static int ocfs2_try_to_merge_extent(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- int split_index,
- struct ocfs2_extent_rec *split_rec,
- struct ocfs2_merge_ctxt *ctxt)
-
-{
- int ret = 0;
- struct ocfs2_extent_list *el = path_leaf_el(left_path);
- struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
-
- assert(ctxt->c_contig_type != CONTIG_NONE);
-
- if (ctxt->c_split_covers_rec && ctxt->c_has_empty_extent) {
- /*
- * The merge code will need to create an empty
- * extent to take the place of the newly
- * emptied slot. Remove any pre-existing empty
- * extents - having more than one in a leaf is
- * illegal.
- */
- ret = ocfs2_rotate_tree_left(fs, left_path);
- if (ret)
- goto out;
-
- split_index--;
- rec = &el->l_recs[split_index];
- }
-
- if (ctxt->c_contig_type == CONTIG_LEFTRIGHT) {
- /*
- * Left-right contig implies this.
- */
- assert(ctxt->c_split_covers_rec);
- assert(split_index != 0);
-
- /*
- * Since the leftright insert always covers the entire
- * extent, this call will delete the insert record
- * entirely, resulting in an empty extent record added to
- * the extent block.
- *
- * Since the adding of an empty extent shifts
- * everything back to the right, there's no need to
- * update split_index here.
- */
- ret = ocfs2_merge_rec_left(fs, split_rec, el, split_index);
- if (ret)
- goto out;
-
- /*
- * We can only get this from logic error above.
- */
- assert(ocfs2_is_empty_extent(&el->l_recs[0]));
-
- /*
- * The left merge left us with an empty extent, remove
- * it.
- */
- ret = ocfs2_rotate_tree_left(fs, left_path);
- if (ret)
- goto out;
-
- split_index--;
- rec = &el->l_recs[split_index];
-
- /*
- * Note that we don't pass split_rec here on purpose -
- * we've merged it into the left side.
- */
- ret = ocfs2_merge_rec_right(fs, rec, el, split_index);
- if (ret)
- goto out;
-
- assert(ocfs2_is_empty_extent(&el->l_recs[0]));
-
- ret = ocfs2_rotate_tree_left(fs, left_path);
- /*
- * Error from this last rotate is not critical, so
- * don't bubble it up.
- */
- ret = 0;
- } else {
- /*
- * Merge a record to the left or right.
- *
- * 'contig_type' is relative to the existing record,
- * so for example, if we're "right contig", it's to
- * the record on the left (hence the left merge).
- */
- if (ctxt->c_contig_type == CONTIG_RIGHT) {
- ret = ocfs2_merge_rec_left(fs,
- split_rec, el,
- split_index);
- if (ret)
- goto out;
- } else {
- ret = ocfs2_merge_rec_right(fs,
- split_rec, el,
- split_index);
- if (ret)
- goto out;
- }
-
- /* we have to synchronize the modified extent block to disk. */
- if (left_path->p_tree_depth > 0) {
- ret = ocfs2_write_extent_block(fs,
- path_leaf_blkno(left_path),
- path_leaf_buf(left_path));
- if (ret)
- goto out;
- }
-
- if (ctxt->c_split_covers_rec) {
- /*
- * The merge may have left an empty extent in
- * our leaf. Try to rotate it away.
- */
- ret = ocfs2_rotate_tree_left(fs,left_path);
- ret = 0;
- }
- }
-
-out:
- return ret;
-}
-
-static void ocfs2_subtract_from_rec(ocfs2_filesys *fs,
- enum ocfs2_split_type split,
- struct ocfs2_extent_rec *rec,
- struct ocfs2_extent_rec *split_rec)
-{
- uint64_t len_blocks;
-
- len_blocks = ocfs2_clusters_to_blocks(fs, split_rec->e_leaf_clusters);
-
- if (split == SPLIT_LEFT) {
- /*
- * Region is on the left edge of the existing
- * record.
- */
- rec->e_cpos += split_rec->e_leaf_clusters;
- rec->e_blkno += len_blocks;
- rec->e_leaf_clusters -= split_rec->e_leaf_clusters;
- } else {
- /*
- * Region is on the right edge of the existing
- * record.
- */
- rec->e_leaf_clusters -= split_rec->e_leaf_clusters;
- }
-}
-
-/*
- * Change the depth of the tree. That means allocating an extent block,
- * copying all extent records from the dinode into the extent block,
- * and then pointing the dinode to the new extent_block.
- */
-static errcode_t shift_tree_depth(ocfs2_filesys *fs,
- struct ocfs2_dinode *di,
- char **new_eb)
-{
- errcode_t ret;
- char *buf = NULL;
- uint64_t blkno;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
- uint32_t new_clusters;
-
- el = &di->id2.i_list;
- if (el->l_next_free_rec != el->l_count)
- return OCFS2_ET_INTERNAL_FAILURE;
-
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- return ret;
-
- ret = ocfs2_new_extent_block(fs, &blkno);
- if (ret)
- goto out;
-
- ret = ocfs2_read_extent_block(fs, blkno, buf);
- if (ret)
- goto out;
-
- eb = (struct ocfs2_extent_block *)buf;
- eb->h_list.l_tree_depth = el->l_tree_depth;
- eb->h_list.l_next_free_rec = el->l_next_free_rec;
- memcpy(eb->h_list.l_recs, el->l_recs,
- sizeof(struct ocfs2_extent_rec) * el->l_count);
-
- new_clusters = ocfs2_sum_rightmost_rec(&eb->h_list);
-
- el->l_tree_depth++;
- memset(el->l_recs, 0,
- sizeof(struct ocfs2_extent_rec) * el->l_count);
- el->l_recs[0].e_cpos = 0;
- el->l_recs[0].e_blkno = blkno;
- el->l_recs[0].e_int_clusters = new_clusters;
- el->l_next_free_rec = 1;
-
- if (el->l_tree_depth == 1)
- di->i_last_eb_blk = blkno;
-
- ret = ocfs2_write_extent_block(fs, blkno, buf);
- if (!ret)
- *new_eb = buf;
-out:
- if (buf && !*new_eb)
- ocfs2_free(&buf);
-
- return ret;
-}
-
-static enum ocfs2_contig_type
-ocfs2_figure_merge_contig_type(ocfs2_filesys *fs,
- struct ocfs2_extent_list *el, int index,
- struct ocfs2_extent_rec *split_rec)
-{
- struct ocfs2_extent_rec *rec;
- enum ocfs2_contig_type ret = CONTIG_NONE;
-
- /*
- * We're careful to check for an empty extent record here -
- * the merge code will know what to do if it sees one.
- */
-
- if (index > 0) {
- rec = &el->l_recs[index - 1];
- if (index == 1 && ocfs2_is_empty_extent(rec)) {
- if (split_rec->e_cpos == el->l_recs[index].e_cpos)
- ret = CONTIG_RIGHT;
- } else {
- ret = ocfs2_extent_contig(fs, rec, split_rec);
- }
- }
-
- if (index < el->l_next_free_rec - 1) {
- enum ocfs2_contig_type contig_type;
-
- rec = &el->l_recs[index + 1];
- contig_type = ocfs2_extent_contig(fs, rec, split_rec);
-
- if (contig_type == CONTIG_LEFT && ret == CONTIG_RIGHT)
- ret = CONTIG_LEFTRIGHT;
- else if (ret == CONTIG_NONE)
- ret = contig_type;
- }
-
- return ret;
-}
-
-static void ocfs2_figure_contig_type(ocfs2_filesys *fs,
- struct ocfs2_insert_type *insert,
- struct ocfs2_extent_list *el,
- struct ocfs2_extent_rec *insert_rec)
-{
- int i;
- enum ocfs2_contig_type contig_type = CONTIG_NONE;
-
- assert(el->l_tree_depth == 0);
-
- for(i = 0; i < el->l_next_free_rec; i++) {
- contig_type = ocfs2_extent_contig(fs, &el->l_recs[i],
- insert_rec);
- if (contig_type != CONTIG_NONE) {
- insert->ins_contig_index = i;
- break;
- }
- }
- insert->ins_contig = contig_type;
-}
-
-/*
- * This should only be called against the righmost leaf extent list.
- *
- * ocfs2_figure_appending_type() will figure out whether we'll have to
- * insert at the tail of the rightmost leaf.
- *
- * This should also work against the dinode list for tree's with 0
- * depth. If we consider the dinode list to be the rightmost leaf node
- * then the logic here makes sense.
- */
-static void ocfs2_figure_appending_type(struct ocfs2_insert_type *insert,
- struct ocfs2_extent_list *el,
- struct ocfs2_extent_rec *insert_rec)
-{
- int i;
- uint32_t cpos = insert_rec->e_cpos;
- struct ocfs2_extent_rec *rec;
-
- insert->ins_appending = APPEND_NONE;
-
- assert(el->l_tree_depth == 0);
-
- if (!el->l_next_free_rec)
- goto set_tail_append;
-
- if (ocfs2_is_empty_extent(&el->l_recs[0])) {
- /* Were all records empty? */
- if (el->l_next_free_rec == 1)
- goto set_tail_append;
- }
-
- i = el->l_next_free_rec - 1;
- rec = &el->l_recs[i];
-
- if (cpos >= (rec->e_cpos + rec->e_leaf_clusters))
- goto set_tail_append;
-
- return;
-
-set_tail_append:
- insert->ins_appending = APPEND_TAIL;
-}
-
-/*
- * Helper function called at the begining of an insert.
- *
- * This computes a few things that are commonly used in the process of
- * inserting into the btree:
- * - Whether the new extent is contiguous with an existing one.
- * - The current tree depth.
- * - Whether the insert is an appending one.
- * - The total # of free records in the tree.
- *
- * All of the information is stored on the ocfs2_insert_type
- * structure.
- */
-static int ocfs2_figure_insert_type(struct insert_ctxt *ctxt,
- char **last_eb_buf,
- int *free_records,
- struct ocfs2_insert_type *insert)
-{
- int ret;
- struct ocfs2_extent_block *eb;
- struct ocfs2_extent_list *el;
- struct ocfs2_dinode *di = ctxt->di;
- struct ocfs2_extent_rec *insert_rec = &ctxt->rec;
- ocfs2_filesys *fs = ctxt->fs;
- struct ocfs2_path *path = NULL;
- char *buf = *last_eb_buf;
-
- insert->ins_split = SPLIT_NONE;
-
- el = &di->id2.i_list;
- insert->ins_tree_depth = el->l_tree_depth;
-
- if (el->l_tree_depth) {
- /*
- * If we have tree depth, we read in the
- * rightmost extent block ahead of time as
- * ocfs2_figure_insert_type() and ocfs2_add_branch()
- * may want it later.
- */
- assert(buf);
- ret = ocfs2_read_extent_block(fs, di->i_last_eb_blk, buf);
- if (ret)
- goto out;
-
- eb = (struct ocfs2_extent_block *) buf;
- el = &eb->h_list;
- }
- /*
- * Unless we have a contiguous insert, we'll need to know if
- * there is room left in our allocation tree for another
- * extent record.
- *
- * XXX: This test is simplistic, we can search for empty
- * extent records too.
- */
- *free_records = el->l_count - el->l_next_free_rec;
-
- if (!insert->ins_tree_depth) {
- ocfs2_figure_contig_type(fs, insert, el, insert_rec);
- ocfs2_figure_appending_type(insert, el, insert_rec);
- return 0;
- }
-
- path = ocfs2_new_inode_path(fs, di);
- if (!path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
- /*
- * In the case that we're inserting past what the tree
- * currently accounts for, ocf2_find_path() will return for
- * us the rightmost tree path. This is accounted for below in
- * the appending code.
- */
- ret = ocfs2_find_path(fs, path, insert_rec->e_cpos);
- if (ret)
- goto out;
-
- el = path_leaf_el(path);
-
- /*
- * Now that we have the path, there's two things we want to determine:
- * 1) Contiguousness (also set contig_index if this is so)
- *
- * 2) Are we doing an append? We can trivially break this up
- * into two types of appends: simple record append, or a
- * rotate inside the tail leaf.
- */
- ocfs2_figure_contig_type(fs, insert, el, insert_rec);
-
- /*
- * The insert code isn't quite ready to deal with all cases of
- * left contiguousness. Specifically, if it's an insert into
- * the 1st record in a leaf, it will require the adjustment of
- * e_clusters on the last record of the path directly to it's
- * left. For now, just catch that case and fool the layers
- * above us. This works just fine for tree_depth == 0, which
- * is why we allow that above.
- */
- if (insert->ins_contig == CONTIG_LEFT &&
- insert->ins_contig_index == 0)
- insert->ins_contig = CONTIG_NONE;
-
- /*
- * Ok, so we can simply compare against last_eb to figure out
- * whether the path doesn't exist. This will only happen in
- * the case that we're doing a tail append, so maybe we can
- * take advantage of that information somehow.
- */
- if (di->i_last_eb_blk == path_leaf_blkno(path)) {
- /*
- * Ok, ocfs2_find_path() returned us the rightmost
- * tree path. This might be an appending insert. There are
- * two cases:
- * 1) We're doing a true append at the tail:
- * -This might even be off the end of the leaf
- * 2) We're "appending" by rotating in the tail
- */
- ocfs2_figure_appending_type(insert, el, insert_rec);
- }
-
-out:
- ocfs2_free_path(path);
-
- return ret;
-}
-
-/*
- * Do the final bits of extent record insertion at the target leaf
- * list. If this leaf is part of an allocation tree, it is assumed
- * that the tree above has been prepared.
- */
-static void ocfs2_insert_at_leaf(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *insert_rec,
- struct ocfs2_extent_list *el,
- struct ocfs2_insert_type *insert)
-{
- int i = insert->ins_contig_index;
- unsigned int range;
- struct ocfs2_extent_rec *rec;
-
- assert(el->l_tree_depth == 0);
-
- if (insert->ins_split != SPLIT_NONE) {
- i = ocfs2_search_extent_list(el, insert_rec->e_cpos);
- assert(i != -1);
- rec = &el->l_recs[i];
- ocfs2_subtract_from_rec(fs, insert->ins_split, rec,
- insert_rec);
- goto rotate;
- }
-
- /*
- * Contiguous insert - either left or right.
- */
- if (insert->ins_contig != CONTIG_NONE) {
- rec = &el->l_recs[i];
- if (insert->ins_contig == CONTIG_LEFT) {
- rec->e_blkno = insert_rec->e_blkno;
- rec->e_cpos = insert_rec->e_cpos;
- }
- rec->e_leaf_clusters += insert_rec->e_leaf_clusters;
- return;
- }
-
- /*
- * Handle insert into an empty leaf.
- */
- if (el->l_next_free_rec == 0 ||
- (el->l_next_free_rec == 1 &&
- ocfs2_is_empty_extent(&el->l_recs[0]))) {
- el->l_recs[0] = *insert_rec;
- el->l_next_free_rec = 1;
- return;
- }
-
- /*
- * Appending insert.
- */
- if (insert->ins_appending == APPEND_TAIL) {
- i = el->l_next_free_rec - 1;
- rec = &el->l_recs[i];
- range = rec->e_cpos + rec->e_leaf_clusters;
- assert(insert_rec->e_cpos >= range);
-
- i++;
- el->l_recs[i] = *insert_rec;
- el->l_next_free_rec += 1;
- return;
- }
-
-rotate:
- /*
- * Ok, we have to rotate.
- *
- * At this point, it is safe to assume that inserting into an
- * empty leaf and appending to a leaf have both been handled
- * above.
- *
- * This leaf needs to have space, either by the empty 1st
- * extent record, or by virtue of an l_next_rec < l_count.
- */
- ocfs2_rotate_leaf(el, insert_rec);
-}
-
-static int ocfs2_adjust_rightmost_records(ocfs2_filesys *fs,
- struct ocfs2_path *path,
- struct ocfs2_extent_rec *insert_rec)
-{
- int i, next_free;
- struct ocfs2_extent_list *el;
- struct ocfs2_extent_rec *rec;
-
- /*
- * Update everything except the leaf block.
- */
- for (i = 0; i < path->p_tree_depth; i++) {
- el = path->p_node[i].el;
-
- next_free = el->l_next_free_rec;
- if (next_free == 0)
- return OCFS2_ET_CORRUPT_EXTENT_BLOCK;
-
- rec = &el->l_recs[next_free - 1];
-
- rec->e_int_clusters = insert_rec->e_cpos;
- rec->e_int_clusters += insert_rec->e_leaf_clusters;
- rec->e_int_clusters -= rec->e_cpos;
- }
-
- return 0;
-}
-
-static int ocfs2_append_rec_to_path(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *insert_rec,
- struct ocfs2_path *right_path,
- struct ocfs2_path **ret_left_path)
-{
- int ret, next_free;
- struct ocfs2_extent_list *el;
- struct ocfs2_path *left_path = NULL;
-
- *ret_left_path = NULL;
-
- /*
- * This shouldn't happen for non-trees. The extent rec cluster
- * count manipulation below only works for interior nodes.
- */
- assert(right_path->p_tree_depth > 0);
-
- /*
- * If our appending insert is at the leftmost edge of a leaf,
- * then we might need to update the rightmost records of the
- * neighboring path.
- */
-
- el = path_leaf_el(right_path);
- next_free = el->l_next_free_rec;
- if (next_free == 0 ||
- (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0]))) {
- uint32_t left_cpos;
-
- ret = ocfs2_find_cpos_for_left_leaf(right_path, &left_cpos);
- if (ret)
- goto out;
- /*
- * No need to worry if the append is already in the
- * leftmost leaf.
- */
- if (left_cpos) {
- left_path = ocfs2_new_path(fs,
- path_root_buf(right_path),
- path_root_el(right_path));
- if (!left_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- ret = ocfs2_find_path(fs, left_path, left_cpos);
- if (ret)
- goto out;
- }
- }
-
- ret = ocfs2_adjust_rightmost_records(fs, right_path, insert_rec);
- if (ret)
- goto out;
-
- *ret_left_path = left_path;
- ret = 0;
-out:
- if (ret)
- ocfs2_free_path(left_path);
- return ret;
-}
-
-static void ocfs2_split_record(ocfs2_filesys *fs,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- struct ocfs2_extent_rec *split_rec,
- enum ocfs2_split_type split)
-{
- int index;
- uint32_t cpos = split_rec->e_cpos;
- struct ocfs2_extent_list *left_el = NULL, *right_el, *insert_el, *el;
- struct ocfs2_extent_rec *rec, *tmprec;
-
- right_el = path_leaf_el(right_path);;
- if (left_path)
- left_el = path_leaf_el(left_path);
-
- el = right_el;
- insert_el = right_el;
- index = ocfs2_search_extent_list(el, cpos);
- if (index != -1) {
- if (index == 0 && left_path) {
- assert(!ocfs2_is_empty_extent(&el->l_recs[0]));
-
- /*
- * This typically means that the record
- * started in the left path but moved to the
- * right as a result of rotation. We either
- * move the existing record to the left, or we
- * do the later insert there.
- *
- * In this case, the left path should always
- * exist as the rotate code will have passed
- * it back for a post-insert update.
- */
-
- if (split == SPLIT_LEFT) {
- /*
- * It's a left split. Since we know
- * that the rotate code gave us an
- * empty extent in the left path, we
- * can just do the insert there.
- */
- insert_el = left_el;
- } else {
- /*
- * Right split - we have to move the
- * existing record over to the left
- * leaf. The insert will be into the
- * newly created empty extent in the
- * right leaf.
- */
- tmprec = &right_el->l_recs[index];
- ocfs2_rotate_leaf(left_el, tmprec);
- el = left_el;
-
- memset(tmprec, 0, sizeof(*tmprec));
- index = ocfs2_search_extent_list(left_el, cpos);
- assert(index != -1);
- }
- }
- } else {
- assert(left_path);
- assert(ocfs2_is_empty_extent(&left_el->l_recs[0]));
- /*
- * Left path is easy - we can just allow the insert to
- * happen.
- */
- el = left_el;
- insert_el = left_el;
- index = ocfs2_search_extent_list(el, cpos);
- assert(index != -1);
- }
-
- rec = &el->l_recs[index];
- ocfs2_subtract_from_rec(fs, split, rec, split_rec);
- ocfs2_rotate_leaf(insert_el, split_rec);
-}
-
-/*
- * This function only does inserts on an allocation b-tree. For dinode
- * lists, ocfs2_insert_at_leaf() is called directly.
- *
- * right_path is the path we want to do the actual insert
- * in. left_path should only be passed in if we need to update that
- * portion of the tree after an edge insert.
- */
-static int ocfs2_insert_path(struct insert_ctxt* ctxt,
- struct ocfs2_path *left_path,
- struct ocfs2_path *right_path,
- struct ocfs2_extent_rec *insert_rec,
- struct ocfs2_insert_type *insert)
-{
- int ret, subtree_index;
-
- if (insert->ins_split != SPLIT_NONE) {
- /*
- * We could call ocfs2_insert_at_leaf() for some types
- * of splits, but it's easier to just let one seperate
- * function sort it all out.
- */
- ocfs2_split_record(ctxt->fs, left_path, right_path,
- insert_rec, insert->ins_split);
- } else
- ocfs2_insert_at_leaf(ctxt->fs, insert_rec, path_leaf_el(right_path),
- insert);
-
- if (left_path) {
- /*
- * The rotate code has indicated that we need to fix
- * up portions of the tree after the insert.
- */
- subtree_index = ocfs2_find_subtree_root(left_path, right_path);
- ocfs2_complete_edge_insert(ctxt->fs, left_path,
- right_path, subtree_index);
- } else
- subtree_index = 0;
-
- ret = ocfs2_sync_path_to_disk(ctxt->fs, left_path,
- right_path, subtree_index);
- if (ret)
- goto out;
-
- ret = 0;
-out:
- return ret;
-}
-
-static int ocfs2_do_insert_extent(struct insert_ctxt* ctxt,
- struct ocfs2_insert_type *type)
-{
- int ret, rotate = 0;
- uint32_t cpos;
- struct ocfs2_path *right_path = NULL;
- struct ocfs2_path *left_path = NULL;
- struct ocfs2_extent_rec *insert_rec = &ctxt->rec;
- ocfs2_filesys *fs = ctxt->fs;
- struct ocfs2_dinode *di = ctxt->di;
- struct ocfs2_extent_list *el = &di->id2.i_list;
-
- if (el->l_tree_depth == 0) {
- ocfs2_insert_at_leaf(fs, insert_rec, el, type);
- goto out_update_clusters;
- }
-
- right_path = ocfs2_new_inode_path(fs, di);
- if (!right_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- /*
- * Determine the path to start with. Rotations need the
- * rightmost path, everything else can go directly to the
- * target leaf.
- */
- cpos = insert_rec->e_cpos;
- if (type->ins_appending == APPEND_NONE &&
- type->ins_contig == CONTIG_NONE) {
- rotate = 1;
- cpos = UINT_MAX;
- }
-
- ret = ocfs2_find_path(fs, right_path, cpos);
- if (ret)
- goto out;
-
- /*
- * Rotations and appends need special treatment - they modify
- * parts of the tree's above them.
- *
- * Both might pass back a path immediate to the left of the
- * one being inserted to. This will be cause
- * ocfs2_insert_path() to modify the rightmost records of
- * left_path to account for an edge insert.
- *
- * XXX: When modifying this code, keep in mind that an insert
- * can wind up skipping both of these two special cases...
- */
-
- if (rotate) {
- ret = ocfs2_rotate_tree_right(fs, type->ins_split,
- insert_rec->e_cpos,
- right_path, &left_path);
- if (ret)
- goto out;
- } else if (type->ins_appending == APPEND_TAIL
- && type->ins_contig != CONTIG_LEFT) {
- ret = ocfs2_append_rec_to_path(fs, insert_rec,
- right_path, &left_path);
- if (ret)
- goto out;
- }
-
- ret = ocfs2_insert_path(ctxt, left_path, right_path, insert_rec, type);
- if (ret)
- goto out;
-
-out_update_clusters:
- if (type->ins_split == SPLIT_NONE)
- di->i_clusters += insert_rec->e_leaf_clusters;
- ret = 0;
-
-out:
- ocfs2_free_path(left_path);
- ocfs2_free_path(right_path);
-
- return ret;
-}
-
-struct duplicate_ctxt {
- struct ocfs2_dinode *di;
- uint64_t next_leaf_blk;
-};
-
-static errcode_t duplicate_extent_block(ocfs2_filesys *fs,
- struct ocfs2_extent_list *old_el,
- struct ocfs2_extent_list *new_el,
- struct duplicate_ctxt *ctxt)
-{
- int i;
- errcode_t ret;
- uint64_t blkno, new_blkno;
- struct ocfs2_extent_rec *rec = NULL;
- char *eb_buf = NULL, *new_eb_buf = NULL;
- struct ocfs2_extent_block *eb = NULL;
- struct ocfs2_extent_list *child_old_el = NULL, *child_new_el = NULL;
-
- assert (old_el->l_tree_depth > 0);
-
- /* empty the whole extent list at first. */
- *new_el = *old_el;
- new_el->l_next_free_rec = 0;
- memset(new_el->l_recs, 0,
- sizeof(struct ocfs2_extent_rec) * new_el->l_count);
-
- if (old_el->l_next_free_rec == 0) {
- /* XXX:
- * We have a tree depth > 0 and no extent record in it,
- * should it be a corrupted block?
- */
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto bail;
- }
-
- ret = ocfs2_malloc_block(fs->fs_io, &eb_buf);
- if (ret)
- goto bail;
- ret = ocfs2_malloc_block(fs->fs_io, &new_eb_buf);
- if (ret)
- goto bail;
-
- /* we iterate the extent list from the last one for recording
- * the next_leaf_blk for the previous leaf.
- */
- for (i = old_el->l_next_free_rec - 1; i >= 0; i--) {
- rec = &old_el->l_recs[i];
-
- if (!ocfs2_rec_clusters(old_el->l_tree_depth, rec))
- continue;
-
- blkno = rec->e_blkno;
- ret = ocfs2_read_extent_block(fs, blkno, eb_buf);
- if (ret)
- goto bail;
-
- /* First make the new_buf the same as the old buf. */
- memcpy(new_eb_buf, eb_buf, fs->fs_blocksize);
-
- eb = (struct ocfs2_extent_block *)eb_buf;
- child_old_el = &eb->h_list;
- eb = (struct ocfs2_extent_block *)new_eb_buf;
- child_new_el = &eb->h_list;
-
- if (child_old_el->l_tree_depth > 0) {
- /* the extent record in our list still has child extent
- * block, so we have to iterate it.
- */
- ret = duplicate_extent_block(fs,
- child_old_el,
- child_new_el,
- ctxt);
- if (ret)
- goto bail;
- }
-
- /* now we allocate a new extent block and save it. */
- ret = ocfs2_new_extent_block(fs, &new_blkno);
- if (ret)
- goto bail;
-
- eb = (struct ocfs2_extent_block *)new_eb_buf;
- eb->h_blkno = new_blkno;
- if (child_old_el->l_tree_depth == 0) {
- /*
- * This is the leaf blkno, we have to set its
- * h_next_leaf_blk and then record itself for
- * future use.
- */
- eb->h_next_leaf_blk = ctxt->next_leaf_blk;
- ctxt->next_leaf_blk = new_blkno;
- }
-
- ret = ocfs2_write_extent_block(fs, new_blkno, new_eb_buf);
- if (ret)
- goto bail;
-
- memcpy(&new_el->l_recs[i], rec, sizeof(struct ocfs2_extent_rec));
- new_el->l_recs[i].e_blkno = new_blkno;
-
- eb = (struct ocfs2_extent_block *)new_eb_buf;
- /* set the new i_last_eb_blk in the new dinode. */
- if (ctxt->di->i_last_eb_blk == blkno)
- ctxt->di->i_last_eb_blk = new_blkno;
- }
-
- new_el->l_next_free_rec = old_el->l_next_free_rec;
- ret = 0;
-
-bail:
- if (eb_buf)
- ocfs2_free(&eb_buf);
- if (new_eb_buf)
- ocfs2_free(&new_eb_buf);
- /* Free all the extent block we allocate. */
- if (ret) {
- for (i = 0; i < old_el->l_next_free_rec; i++) {
- rec = &new_el->l_recs[i];
- if (rec->e_blkno)
- ocfs2_delete_extent_block(fs, rec->e_blkno);
- }
- }
-
- return ret;
-}
-
-static errcode_t duplicate_extent_block_dinode(ocfs2_filesys *fs,
- char *old_buf, char *new_buf)
-{
- errcode_t ret = 0;
- struct ocfs2_dinode *old_di = NULL, *new_di = NULL;
- struct ocfs2_extent_list *old_el = NULL, *new_el = NULL;
- struct duplicate_ctxt ctxt;
-
- old_di = (struct ocfs2_dinode *)old_buf;
- old_el = &old_di->id2.i_list;
- new_di = (struct ocfs2_dinode *)new_buf;
- new_el = &new_di->id2.i_list;
-
- assert(old_el->l_tree_depth > 0);
-
- /* empty the whole extent list at first. */
- *new_el = *old_el;
- memset(new_el->l_recs, 0,
- sizeof(struct ocfs2_extent_rec) * new_el->l_count);
- new_el->l_next_free_rec = 0;
-
- memset(&ctxt, 0, sizeof(ctxt));
- ctxt.di = new_di;
- ctxt.next_leaf_blk = 0;
- ret = duplicate_extent_block(fs, old_el, new_el, &ctxt);
-
- return ret;
-}
-
-static void free_duplicated_extent_block(ocfs2_filesys *fs,
- struct ocfs2_extent_list *el)
-{
- int i;
- errcode_t ret;
- char *buf = NULL;
- struct ocfs2_extent_rec *rec;
- struct ocfs2_extent_list *child_el;
- struct ocfs2_extent_block *eb;
-
- assert(el->l_tree_depth > 0);
-
- ret = ocfs2_malloc_block(fs->fs_io, &buf);
- if (ret)
- return;
-
- for (i = 0; i < el->l_next_free_rec; i ++) {
- rec = &el->l_recs[i];
-
- if (!ocfs2_rec_clusters(el->l_tree_depth, rec))
- continue;
-
- ret = ocfs2_read_extent_block(fs, rec->e_blkno, buf);
- if (ret)
- continue;
-
- eb = (struct ocfs2_extent_block *)buf;
- child_el = &eb->h_list;
- if (child_el->l_tree_depth > 0)
- free_duplicated_extent_block(fs, child_el);
-
- ocfs2_delete_extent_block(fs, rec->e_blkno);
- }
-
- if(buf)
- ocfs2_free(&buf);
-}
-
-static void free_duplicated_extent_block_dinode(ocfs2_filesys *fs,
- char *di_buf)
-{
- struct ocfs2_dinode *di = NULL;
- struct ocfs2_extent_list *el = NULL;
-
- di = (struct ocfs2_dinode *)di_buf;
- el = &di->id2.i_list;
-
- assert(el->l_tree_depth > 0);
-
- free_duplicated_extent_block(fs, el);
-}
-
-/*
- * Grow a b-tree so that it has more records.
- *
- * We might shift the tree depth in which case existing paths should
- * be considered invalid.
- *
- * Tree depth after the grow is returned via *final_depth.
- *
- * *last_eb will be updated by ocfs2_add_branch().
- */
-static int ocfs2_grow_tree(ocfs2_filesys *fs, struct ocfs2_dinode *di,
- int *final_depth, char **last_eb)
-{
- errcode_t ret;
- char *eb_buf = NULL;
- int shift;
- int depth = di->id2.i_list.l_tree_depth;
-
- shift = ocfs2_find_branch_target(fs, di, &eb_buf);
- if (shift < 0) {
- ret = shift;
- goto out;
- }
-
- /* We traveled all the way to the bottom of the allocation tree
- * and didn't find room for any more extents - we need to add
- * another tree level */
- if (shift) {
-
- /* shift_tree_depth will return us a buffer with
- * the new extent block (so we can pass that to
- * ocfs2_add_branch). */
- ret = shift_tree_depth(fs, di, &eb_buf);
- if (ret)
- goto out;
-
- depth++;
- if (depth == 1) {
- /*
- * Special case: we have room now if we shifted from
- * tree_depth 0, so no more work needs to be done.
- *
- * We won't be calling add_branch, so pass
- * back *last_eb as the new leaf.
- */
- assert(*last_eb);
- memcpy(*last_eb, eb_buf, fs->fs_blocksize);
- goto out;
- }
- }
-
- /* call ocfs2_add_branch to add the final part of the tree with
- * the new data. */
- ret = ocfs2_add_branch(fs, di, eb_buf, last_eb);
-
-out:
- if (final_depth)
- *final_depth = depth;
- return ret;
-}
-
-/*
- * Insert an extent into an inode btree.
- */
-errcode_t ocfs2_insert_extent(ocfs2_filesys *fs, uint64_t ino, uint32_t cpos,
- uint64_t c_blkno, uint32_t clusters,
- uint16_t flag)
-{
- errcode_t ret;
- ocfs2_cached_inode *ci = NULL;
-
- ret = ocfs2_read_cached_inode(fs, ino, &ci);
- if (ret)
- goto bail;
-
- ret = ocfs2_cached_inode_insert_extent(ci, cpos, c_blkno,
- clusters, flag);
- if (ret)
- goto bail;
-
- ret = ocfs2_write_cached_inode(fs, ci);
-
-bail:
- if (ci)
- ocfs2_free_cached_inode(fs, ci);
-
- return ret;
-}
-
-errcode_t ocfs2_cached_inode_insert_extent(ocfs2_cached_inode *ci,
- uint32_t cpos, uint64_t c_blkno,
- uint32_t clusters, uint16_t flag)
-{
- errcode_t ret;
- struct insert_ctxt ctxt;
- struct ocfs2_insert_type insert = {0, };
- char *last_eb = NULL;
- char *backup_buf = NULL;
- char *di_buf = NULL;
- int free_records = 0;
- ocfs2_filesys *fs = ci->ci_fs;
-
- ctxt.fs = fs;
- ctxt.di = ci->ci_inode;
- di_buf = (char *)ctxt.di;
-
- /* In order to orderize the written block sequence and avoid
- * the corruption for the inode, we duplicate the extent block
- * here and do the insertion in the duplicated ones.
- *
- * Note: we only do this in case the file has extent blocks.
- * And if the duplicate process fails, we should go on the normal
- * insert process.
- */
- if (ctxt.di->id2.i_list.l_tree_depth) {
- ret = ocfs2_malloc_block(fs->fs_io, &backup_buf);
- if (ret)
- goto bail;
-
- memcpy(backup_buf, di_buf, fs->fs_blocksize);
-
- /* duplicate the extent block. If it succeeds, di_buf
- * will point to the new allocated extent blocks, and
- * the following insertion will happens to the new ones.
- */
- ret = duplicate_extent_block_dinode(fs, backup_buf, di_buf);
- if (ret) {
- memcpy(di_buf, backup_buf,fs->fs_blocksize);
- ocfs2_free(&backup_buf);
- backup_buf = NULL;
- }
- }
-
- memset(&ctxt.rec, 0, sizeof(struct ocfs2_extent_rec));
- ctxt.rec.e_cpos = cpos;
- ctxt.rec.e_blkno = c_blkno;
- ctxt.rec.e_leaf_clusters = clusters;
- ctxt.rec.e_flags = flag;
-
- ret = ocfs2_malloc_block(fs->fs_io, &last_eb);
- if (ret)
- return ret;
-
- ret = ocfs2_figure_insert_type(&ctxt, &last_eb, &free_records, &insert);
- if (ret)
- goto bail;
-
- if (insert.ins_contig == CONTIG_NONE && free_records == 0) {
- ret = ocfs2_grow_tree(fs, ctxt.di,
- &insert.ins_tree_depth, &last_eb);
- if (ret)
- goto bail;
- }
-
- /* Finally, we can add clusters. This might rotate the tree for us. */
- ret = ocfs2_do_insert_extent(&ctxt, &insert);
- if (ret)
- goto bail;
-
-bail:
- if (backup_buf) {
- /* we have duplicated the extent block during the insertion.
- * so if it succeeds, we should free the old ones, and if fails,
- * the duplicate ones should be freed.
- */
- if (ret)
- free_duplicated_extent_block_dinode(fs, di_buf);
- else
- free_duplicated_extent_block_dinode(fs, backup_buf);
- ocfs2_free(&backup_buf);
- }
-
- if (last_eb)
- ocfs2_free(&last_eb);
-
- return ret;
-}
-
-static void ocfs2_make_right_split_rec(ocfs2_filesys *fs,
- struct ocfs2_extent_rec *split_rec,
- uint32_t cpos,
- struct ocfs2_extent_rec *rec)
-{
- uint32_t rec_cpos = rec->e_cpos;
- uint32_t rec_range = rec_cpos + rec->e_leaf_clusters;
-
- memset(split_rec, 0, sizeof(struct ocfs2_extent_rec));
-
- split_rec->e_cpos = cpos;
- split_rec->e_leaf_clusters = rec_range - cpos;
-
- split_rec->e_blkno = rec->e_blkno;
- split_rec->e_blkno += ocfs2_clusters_to_blocks(fs, cpos - rec_cpos);
-
- split_rec->e_flags = rec->e_flags;
-}
-
-static int ocfs2_split_and_insert(struct insert_ctxt *ctxt,
- struct ocfs2_path *path,
- char **last_eb_buf,
- int split_index,
- struct ocfs2_extent_rec *orig_split_rec)
-{
- int ret = 0, depth;
- unsigned int insert_range, rec_range, do_leftright = 0;
- struct ocfs2_extent_rec tmprec;
- struct ocfs2_extent_list *rightmost_el;
- struct ocfs2_extent_rec rec;
- struct ocfs2_insert_type insert;
- struct ocfs2_extent_block *eb;
-
-leftright:
- /*
- * Store a copy of the record on the stack - it might move
- * around as the tree is manipulated below.
- */
- rec = path_leaf_el(path)->l_recs[split_index];
-
- rightmost_el = &ctxt->di->id2.i_list;
-
- depth = rightmost_el->l_tree_depth;
- if (depth) {
- assert(*last_eb_buf);
- eb = (struct ocfs2_extent_block *) (*last_eb_buf);
- rightmost_el = &eb->h_list;
- }
-
- if (rightmost_el->l_next_free_rec == rightmost_el->l_count) {
- ret = ocfs2_grow_tree(ctxt->fs, ctxt->di, &depth, last_eb_buf);
- if (ret)
- goto out;
- }
-
- memset(&insert, 0, sizeof(struct ocfs2_insert_type));
- insert.ins_appending = APPEND_NONE;
- insert.ins_contig = CONTIG_NONE;
- insert.ins_tree_depth = depth;
-
- insert_range = ctxt->rec.e_cpos + ctxt->rec.e_leaf_clusters;
- rec_range = rec.e_cpos + rec.e_leaf_clusters;
-
- if (ctxt->rec.e_cpos == rec.e_cpos) {
- insert.ins_split = SPLIT_LEFT;
- } else if (insert_range == rec_range) {
- insert.ins_split = SPLIT_RIGHT;
- } else {
- /*
- * Left/right split. We fake this as a right split
- * first and then make a second pass as a left split.
- */
- insert.ins_split = SPLIT_RIGHT;
-
- ocfs2_make_right_split_rec(ctxt->fs, &tmprec, insert_range,
- &rec);
-
- ctxt->rec = tmprec;
-
- assert(!do_leftright);
- do_leftright = 1;
- }
-
- ret = ocfs2_do_insert_extent(ctxt, &insert);
- if (ret)
- goto out;
-
- if (do_leftright == 1) {
- uint32_t cpos;
- struct ocfs2_extent_list *el;
-
- do_leftright++;
- ctxt->rec = *orig_split_rec;
-
- ocfs2_reinit_path(path, 1);
-
- cpos = ctxt->rec.e_cpos;
- ret = ocfs2_find_path(ctxt->fs, path, cpos);
- if (ret)
- goto out;
-
- el = path_leaf_el(path);
- split_index = ocfs2_search_extent_list(el, cpos);
- goto leftright;
- }
-out:
-
- return ret;
-}
-
-/*
- * Mark part or all of the extent record at split_index in the leaf
- * pointed to by path as written. This removes the unwritten
- * extent flag.
- *
- * Care is taken to handle contiguousness so as to not grow the tree.
- *
- * last_eb_buf should be the rightmost leaf block for any inode with a
- * btree. Since a split may grow the tree or a merge might shrink it,
- * the caller cannot trust the contents of that buffer after this call.
- *
- * This code is optimized for readability - several passes might be
- * made over certain portions of the tree.
- */
-static int __ocfs2_mark_extent_written(struct insert_ctxt *insert_ctxt,
- struct ocfs2_path *path,
- int split_index)
-{
- int ret = 0;
- struct ocfs2_extent_rec split_rec = insert_ctxt->rec;
- struct ocfs2_extent_list *el = path_leaf_el(path);
- char *last_eb_buf = NULL;
- struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
- struct ocfs2_merge_ctxt merge_ctxt;
- struct ocfs2_extent_list *rightmost_el;
- ocfs2_filesys *fs = insert_ctxt->fs;
-
- if (!rec->e_flags & OCFS2_EXT_UNWRITTEN) {
- ret = OCFS2_ET_INVALID_ARGUMENT;
- goto out;
- }
-
- if (rec->e_cpos > split_rec.e_cpos ||
- ((rec->e_cpos + rec->e_leaf_clusters) <
- (split_rec.e_cpos + split_rec.e_leaf_clusters))) {
- ret = OCFS2_ET_INVALID_ARGUMENT;
- goto out;
- }
-
- merge_ctxt.c_contig_type = ocfs2_figure_merge_contig_type(fs, el,
- split_index,
- &split_rec);
-
- /*
- * We have to allocate the last_eb_buf no matter the current tree
- * depth is since we may shift the tree depth from 0 to 1 in
- * ocfs2_split_and_insert and use last_eb_buf to store.
- */
- ret = ocfs2_malloc_block(fs->fs_io, &last_eb_buf);
- if (ret)
- goto out;
- /*
- * The core merge / split code wants to know how much room is
- * left in this inodes allocation tree, so we pass the
- * rightmost extent list.
- */
- if (path->p_tree_depth) {
- struct ocfs2_extent_block *eb;
- struct ocfs2_dinode *di = insert_ctxt->di;
-
- ret = ocfs2_read_extent_block(fs,
- di->i_last_eb_blk,
- last_eb_buf);
- if (ret)
- goto out;
-
- eb = (struct ocfs2_extent_block *) last_eb_buf;
-
- rightmost_el = &eb->h_list;
- } else
- rightmost_el = path_root_el(path);
-
- if (rec->e_cpos == split_rec.e_cpos &&
- rec->e_leaf_clusters == split_rec.e_leaf_clusters)
- merge_ctxt.c_split_covers_rec = 1;
- else
- merge_ctxt.c_split_covers_rec = 0;
-
- merge_ctxt.c_has_empty_extent = ocfs2_is_empty_extent(&el->l_recs[0]);
-
- if (merge_ctxt.c_contig_type == CONTIG_NONE) {
- if (merge_ctxt.c_split_covers_rec)
- el->l_recs[split_index] = split_rec;
- else
- ret = ocfs2_split_and_insert(insert_ctxt, path,
- &last_eb_buf, split_index,
- &split_rec);
- } else {
- ret = ocfs2_try_to_merge_extent(fs, path,
- split_index, &split_rec,
- &merge_ctxt);
- }
-
-out:
- if (last_eb_buf)
- ocfs2_free(&last_eb_buf);
- return ret;
-}
-
-/*
- * Mark the already-existing extent at cpos as written for len clusters.
- *
- * If the existing extent is larger than the request, initiate a
- * split. An attempt will be made at merging with adjacent extents.
- *
- */
-int ocfs2_mark_extent_written(ocfs2_filesys *fs, struct ocfs2_dinode *di,
- uint32_t cpos, uint32_t len,
- uint64_t p_blkno)
-{
- int ret, index;
- struct ocfs2_path *left_path = NULL;
- struct ocfs2_extent_list *el;
- struct insert_ctxt ctxt;
- char *backup_buf = NULL, *di_buf = NULL;
-
- if (!ocfs2_writes_unwritten_extents(OCFS2_RAW_SB(fs->fs_super)))
- return OCFS2_ET_UNSUPP_FEATURE;
-
- /* In order to orderize the written block sequence and avoid
- * the corruption for the inode, we duplicate the extent block
- * here and do the insertion in the duplicated ones.
- *
- * Note: we only do this in case the file has extent blocks.
- * And if the duplicate process fails, we should go on the normal
- * insert process.
- */
- di_buf = (char *)di;
- if (di->id2.i_list.l_tree_depth) {
- ret = ocfs2_malloc_block(fs->fs_io, &backup_buf);
- if (ret)
- goto out;
-
- memcpy(backup_buf, di_buf, fs->fs_blocksize);
-
- /* duplicate the extent block. If it succeeds, di_buf
- * will point to the new allocated extent blocks, and
- * the following insertion will happens to the new ones.
- */
- ret = duplicate_extent_block_dinode(fs, backup_buf, di_buf);
- if (ret) {
- memcpy(di_buf, backup_buf,fs->fs_blocksize);
- ocfs2_free(&backup_buf);
- backup_buf = NULL;
- }
- }
-
- left_path = ocfs2_new_inode_path(fs, di);
- if (!left_path) {
- ret = OCFS2_ET_NO_MEMORY;
- goto out;
- }
-
- ret = ocfs2_find_path(fs, left_path, cpos);
- if (ret)
- goto out;
-
- el = path_leaf_el(left_path);
-
- index = ocfs2_search_extent_list(el, cpos);
- if (index == -1 || index >= el->l_next_free_rec) {
- ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
- goto out;
- }
-
- ctxt.fs = fs;
- ctxt.di = di;
-
- memset(&ctxt.rec, 0, sizeof(struct ocfs2_extent_rec));
- ctxt.rec.e_cpos = cpos;
- ctxt.rec.e_leaf_clusters = len;
- ctxt.rec.e_blkno = p_blkno;
- ctxt.rec.e_flags = path_leaf_el(left_path)->l_recs[index].e_flags;
- ctxt.rec.e_flags &= ~OCFS2_EXT_UNWRITTEN;
-
- ret = __ocfs2_mark_extent_written(&ctxt, left_path, index);
- if (ret)
- goto out;
-
- ret = ocfs2_write_inode(fs, di->i_blkno, di_buf);
-
-out:
- if (backup_buf) {
- /* we have duplicated the extent block during the insertion.
- * so if it succeeds, we should free the old ones, and if fails,
- * the duplicate ones should be freed.
- */
- if (ret)
- free_duplicated_extent_block_dinode(fs, di_buf);
- else
- free_duplicated_extent_block_dinode(fs, backup_buf);
- ocfs2_free(&backup_buf);
- }
- ocfs2_free_path(left_path);
- return ret;
-}
errcode_t ocfs2_cached_inode_extend_allocation(ocfs2_cached_inode *ci,
uint32_t new_clusters)
diff --git a/libocfs2/extent_tree.c b/libocfs2/extent_tree.c
index e4f59a9..07c0e46 100644
--- a/libocfs2/extent_tree.c
+++ b/libocfs2/extent_tree.c
@@ -17,6 +17,8 @@
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
+#include <errno.h>
+#include <assert.h>
#include "ocfs2/byteorder.h"
#include "ocfs2/ocfs2.h"
@@ -87,3 +89,3732 @@ void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et,
ocfs2_write_inode,
buf, &ocfs2_dinode_et_ops);
}
+
+/*
+ * Structures which describe a path through a btree, and functions to
+ * manipulate them.
+ *
+ * The idea here is to be as generic as possible with the tree
+ * manipulation code.
+ */
+struct ocfs2_path_item {
+ uint64_t blkno;
+ char *buf;
+ struct ocfs2_extent_list *el;
+};
+
+#define OCFS2_MAX_PATH_DEPTH 5
+
+struct ocfs2_path {
+ int p_tree_depth;
+ struct ocfs2_path_item p_node[OCFS2_MAX_PATH_DEPTH];
+};
+
+#define path_root_blkno(_path) ((_path)->p_node[0].blkno)
+#define path_root_buf(_path) ((_path)->p_node[0].buf)
+#define path_root_el(_path) ((_path)->p_node[0].el)
+#define path_leaf_blkno(_path) ((_path)->p_node[(_path)->p_tree_depth].blkno)
+#define path_leaf_buf(_path) ((_path)->p_node[(_path)->p_tree_depth].buf)
+#define path_leaf_el(_path) ((_path)->p_node[(_path)->p_tree_depth].el)
+#define path_num_items(_path) ((_path)->p_tree_depth + 1)
+
+struct insert_ctxt {
+ ocfs2_filesys *fs;
+ struct ocfs2_dinode *di;
+ struct ocfs2_extent_rec rec;
+};
+/*
+ * Reset the actual path elements so that we can re-use the structure
+ * to build another path. Generally, this involves freeing the buffer
+ * heads.
+ */
+static void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root)
+{
+ int i, start = 0, depth = 0;
+ struct ocfs2_path_item *node;
+
+ if (keep_root)
+ start = 1;
+
+ for(i = start; i < path_num_items(path); i++) {
+ node = &path->p_node[i];
+ if (!node->buf)
+ continue;
+
+ ocfs2_free(&node->buf);
+ node->blkno = 0;
+ node->buf = NULL;
+ node->el = NULL;
+ }
+
+ /*
+ * Tree depth may change during truncate, or insert. If we're
+ * keeping the root extent list, then make sure that our path
+ * structure reflects the proper depth.
+ */
+ if (keep_root)
+ depth = path_root_el(path)->l_tree_depth;
+
+ path->p_tree_depth = depth;
+}
+
+static void ocfs2_free_path(struct ocfs2_path *path)
+{
+ /* We don't free the root because often in libocfs2 the root is a
+ * shared buffer such as the inode. Caller must be responsible for
+ * handling the root of the path.
+ */
+ if (path) {
+ ocfs2_reinit_path(path, 1);
+ ocfs2_free(&path);
+ }
+}
+
+/*
+ * All the elements of src into dest. After this call, src could be freed
+ * without affecting dest.
+ *
+ * Both paths should have the same root. Any non-root elements of dest
+ * will be freed.
+ */
+static void ocfs2_cp_path(ocfs2_filesys *fs,
+ struct ocfs2_path *dest,
+ struct ocfs2_path *src)
+{
+ int i;
+ struct ocfs2_extent_block *eb = NULL;
+
+ assert(path_root_blkno(dest) == path_root_blkno(src));
+ dest->p_tree_depth = src->p_tree_depth;
+
+ for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
+ if (!src->p_node[i].buf) {
+ if (dest->p_node[i].buf)
+ ocfs2_free(dest->p_node[i].buf);
+ dest->p_node[i].blkno = 0;
+ dest->p_node[i].buf = NULL;
+ dest->p_node[i].el = NULL;
+ continue;
+ }
+
+ if (!dest->p_node[i].buf)
+ ocfs2_malloc_block(fs->fs_io, &dest->p_node[i].buf);
+
+ assert(dest->p_node[i].buf);
+ memcpy(dest->p_node[i].buf, src->p_node[i].buf,
+ fs->fs_blocksize);
+ eb = (struct ocfs2_extent_block *)dest->p_node[i].buf;
+ dest->p_node[i].el = &eb->h_list;
+
+ dest->p_node[i].blkno = src->p_node[i].blkno;
+ }
+}
+
+/*
+ * Make the *dest path the same as src and re-initialize src path to
+ * have a root only.
+ */
+static void ocfs2_mv_path(struct ocfs2_path *dest, struct ocfs2_path *src)
+{
+ int i;
+
+ assert(path_root_blkno(dest) == path_root_blkno(src));
+
+ for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
+ ocfs2_free(&dest->p_node[i].buf);
+
+ dest->p_node[i].blkno = src->p_node[i].blkno;
+ dest->p_node[i].buf = src->p_node[i].buf;
+ dest->p_node[i].el = src->p_node[i].el;
+
+ src->p_node[i].blkno = 0;
+ src->p_node[i].buf = NULL;
+ src->p_node[i].el = NULL;
+ }
+}
+
+/*
+ * Insert an extent block at given index.
+ *
+ * Note:
+ * This buf will be inserted into the path, so the caller shouldn't free it.
+ */
+static inline void ocfs2_path_insert_eb(struct ocfs2_path *path, int index,
+ char *buf)
+{
+ struct ocfs2_extent_block *eb = (struct ocfs2_extent_block *) buf;
+ /*
+ * Right now, no root buf is an extent block, so this helps
+ * catch code errors with dinode trees. The assertion can be
+ * safely removed if we ever need to insert extent block
+ * structures at the root.
+ */
+ assert(index);
+
+ path->p_node[index].blkno = eb->h_blkno;
+ path->p_node[index].buf = (char *)buf;
+ path->p_node[index].el = &eb->h_list;
+}
+
+static struct ocfs2_path *ocfs2_new_path(ocfs2_filesys* fs, char *buf,
+ struct ocfs2_extent_list *root_el)
+{
+ errcode_t ret = 0;
+ struct ocfs2_path *path = NULL;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)buf;
+
+ assert(root_el->l_tree_depth < OCFS2_MAX_PATH_DEPTH);
+
+ ret = ocfs2_malloc0(sizeof(*path), &path);
+ if (path) {
+ path->p_tree_depth = root_el->l_tree_depth;
+ path->p_node[0].blkno = di->i_blkno;
+ path->p_node[0].buf = buf;
+ path->p_node[0].el = root_el;
+ }
+
+ return path;
+}
+
+/*
+ * Allocate and initialize a new path based on a disk inode tree.
+ */
+static struct ocfs2_path *ocfs2_new_inode_path(ocfs2_filesys *fs,
+ struct ocfs2_dinode *di)
+{
+ struct ocfs2_extent_list *el = &di->id2.i_list;
+
+ return ocfs2_new_path(fs, (char *)di, el);
+}
+
+/* Write all the extent block information to the disk.
+ * We write all paths furthur down than subtree_index.
+ * The caller will handle writing the sub_index.
+ */
+static errcode_t ocfs2_write_path_eb(ocfs2_filesys *fs,
+ struct ocfs2_path *path, int sub_index)
+{
+ errcode_t ret;
+ int i;
+
+ for (i = path->p_tree_depth; i > sub_index; i--) {
+ ret = ocfs2_write_extent_block(fs,
+ path->p_node[i].blkno,
+ path->p_node[i].buf);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* some extent blocks is modified and we need to synchronize them to the disk
+ * accordingly.
+ *
+ * We will not update the inode if subtree_index is "0" since it should be
+ * updated by the caller.
+ *
+ * left_path or right_path can be NULL, but they can't be NULL in the same time.
+ * And if they are both not NULL, we will treat subtree_index in the right_path
+ * as the right extent block information.
+ */
+static errcode_t ocfs2_sync_path_to_disk(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ int subtree_index)
+{
+ errcode_t ret = 0;
+ struct ocfs2_path *path = NULL;
+
+ assert(left_path || right_path);
+ if (left_path) {
+ ret = ocfs2_write_path_eb(fs, left_path, subtree_index);
+ if (ret)
+ goto bail;
+ }
+
+ if (right_path) {
+ ret = ocfs2_write_path_eb(fs, right_path, subtree_index);
+ if (ret)
+ goto bail;
+ }
+
+ if (subtree_index) {
+ /* subtree_index indicates an extent block. */
+ path = right_path ? right_path : left_path;
+
+ ret = ocfs2_write_extent_block(fs,
+ path->p_node[subtree_index].blkno,
+ path->p_node[subtree_index].buf);
+ if (ret)
+ goto bail;
+ }
+bail:
+ return ret;
+}
+
+/*
+ * Return the index of the extent record which contains cluster #v_cluster.
+ * -1 is returned if it was not found.
+ *
+ * Should work fine on interior and exterior nodes.
+ */
+int ocfs2_search_extent_list(struct ocfs2_extent_list *el, uint32_t v_cluster)
+{
+ int ret = -1;
+ int i;
+ struct ocfs2_extent_rec *rec;
+ uint32_t rec_end, rec_start, clusters;
+
+ for(i = 0; i < el->l_next_free_rec; i++) {
+ rec = &el->l_recs[i];
+
+ rec_start = rec->e_cpos;
+ clusters = ocfs2_rec_clusters(el->l_tree_depth, rec);
+
+ rec_end = rec_start + clusters;
+
+ if (v_cluster >= rec_start && v_cluster < rec_end) {
+ ret = i;
+ break;
+ }
+ }
+
+ return ret;
+}
+
+enum ocfs2_contig_type {
+ CONTIG_NONE = 0,
+ CONTIG_LEFT,
+ CONTIG_RIGHT,
+ CONTIG_LEFTRIGHT,
+};
+
+/*
+ * NOTE: ocfs2_block_extent_contig(), ocfs2_extents_adjacent() and
+ * ocfs2_extent_contig only work properly against leaf nodes!
+ */
+static inline int ocfs2_block_extent_contig(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *ext,
+ uint64_t blkno)
+{
+ uint64_t blk_end = ext->e_blkno;
+
+ blk_end += ocfs2_clusters_to_blocks(fs, ext->e_leaf_clusters);
+
+ return blkno == blk_end;
+}
+
+static inline int ocfs2_extents_adjacent(struct ocfs2_extent_rec *left,
+ struct ocfs2_extent_rec *right)
+{
+ uint32_t left_range;
+
+ left_range = left->e_cpos + left->e_leaf_clusters;
+
+ return (left_range == right->e_cpos);
+}
+
+static enum ocfs2_contig_type
+ ocfs2_extent_contig(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *ext,
+ struct ocfs2_extent_rec *insert_rec)
+{
+ uint64_t blkno = insert_rec->e_blkno;
+
+ /*
+ * Refuse to coalesce extent records with different flag
+ * fields - we don't want to mix unwritten extents with user
+ * data.
+ */
+ if (ext->e_flags != insert_rec->e_flags)
+ return CONTIG_NONE;
+
+ if (ocfs2_extents_adjacent(ext, insert_rec) &&
+ ocfs2_block_extent_contig(fs, ext, blkno))
+ return CONTIG_RIGHT;
+
+ blkno = ext->e_blkno;
+ if (ocfs2_extents_adjacent(insert_rec, ext) &&
+ ocfs2_block_extent_contig(fs, insert_rec, blkno))
+ return CONTIG_LEFT;
+
+ return CONTIG_NONE;
+}
+
+/*
+ * NOTE: We can have pretty much any combination of contiguousness and
+ * appending.
+ *
+ * The usefulness of APPEND_TAIL is more in that it lets us know that
+ * we'll have to update the path to that leaf.
+ */
+enum ocfs2_append_type {
+ APPEND_NONE = 0,
+ APPEND_TAIL,
+};
+
+enum ocfs2_split_type {
+ SPLIT_NONE = 0,
+ SPLIT_LEFT,
+ SPLIT_RIGHT,
+};
+
+struct ocfs2_insert_type {
+ enum ocfs2_split_type ins_split;
+ enum ocfs2_append_type ins_appending;
+ enum ocfs2_contig_type ins_contig;
+ int ins_contig_index;
+ int ins_tree_depth;
+};
+
+struct ocfs2_merge_ctxt {
+ enum ocfs2_contig_type c_contig_type;
+ int c_has_empty_extent;
+ int c_split_covers_rec;
+};
+
+/*
+ * Helper function for ocfs2_add_branch() and shift_tree_depth().
+ *
+ * Returns the sum of the rightmost extent rec logical offset and
+ * cluster count.
+ *
+ * ocfs2_add_branch() uses this to determine what logical cluster
+ * value should be populated into the leftmost new branch records.
+ *
+ * shift_tree_depth() uses this to determine the # clusters
+ * value for the new topmost tree record.
+ */
+static inline uint32_t ocfs2_sum_rightmost_rec(struct ocfs2_extent_list *el)
+{
+ uint16_t i = el->l_next_free_rec - 1;
+
+ return el->l_recs[i].e_cpos +
+ ocfs2_rec_clusters(el->l_tree_depth, &el->l_recs[i]);
+
+}
+
+/*
+ * Add an entire tree branch to our inode. eb_buf is the extent block
+ * to start at, if we don't want to start the branch at the dinode
+ * structure.
+ *
+ * last_eb_buf is required as we have to update it's next_leaf pointer
+ * for the new last extent block.
+ *
+ * the new branch will be 'empty' in the sense that every block will
+ * contain a single record with e_clusters == 0.
+ */
+static int ocfs2_add_branch(ocfs2_filesys *fs,
+ struct ocfs2_dinode *fe,
+ char *eb_buf,
+ char **last_eb_buf)
+{
+ errcode_t ret;
+ int new_blocks, i;
+ uint64_t next_blkno, new_last_eb_blk;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *eb_el;
+ struct ocfs2_extent_list *el;
+ uint32_t new_cpos;
+ uint64_t *new_blknos = NULL;
+ char **new_eb_bufs = NULL;
+ char *buf = NULL;
+
+ assert(*last_eb_buf);
+
+ if (eb_buf) {
+ eb = (struct ocfs2_extent_block *) eb_buf;
+ el = &eb->h_list;
+ } else
+ el = &fe->id2.i_list;
+
+ /* we never add a branch to a leaf. */
+ assert(el->l_tree_depth);
+
+ new_blocks = el->l_tree_depth;
+
+ /* allocate the number of new eb blocks we need new_blocks should be
+ * allocated here.*/
+ ret = ocfs2_malloc0(sizeof(uint64_t) * new_blocks, &new_blknos);
+ if (ret)
+ goto bail;
+ memset(new_blknos, 0, sizeof(uint64_t) * new_blocks);
+
+ ret = ocfs2_malloc0(sizeof(char *) * new_blocks, &new_eb_bufs);
+ if (ret)
+ goto bail;
+ memset(new_eb_bufs, 0, sizeof(char *) * new_blocks);
+
+ for (i = 0; i < new_blocks; i++) {
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ return ret;
+ new_eb_bufs[i] = buf;
+
+ ret = ocfs2_new_extent_block(fs, &new_blknos[i]);
+ if (ret)
+ goto bail;
+
+ ret = ocfs2_read_extent_block(fs, new_blknos[i], buf);
+ if (ret)
+ goto bail;
+ }
+
+ eb = (struct ocfs2_extent_block *)(*last_eb_buf);
+ new_cpos = ocfs2_sum_rightmost_rec(&eb->h_list);
+
+ /* Note: new_eb_bufs[new_blocks - 1] is the guy which will be
+ * linked with the rest of the tree.
+ * conversly, new_eb_bufs[0] is the new bottommost leaf.
+ *
+ * when we leave the loop, new_last_eb_blk will point to the
+ * newest leaf, and next_blkno will point to the topmost extent
+ * block.
+ */
+ next_blkno = new_last_eb_blk = 0;
+ for(i = 0; i < new_blocks; i++) {
+ buf = new_eb_bufs[i];
+ eb = (struct ocfs2_extent_block *) buf;
+ eb_el = &eb->h_list;
+
+ eb->h_next_leaf_blk = 0;
+ eb_el->l_tree_depth = i;
+ eb_el->l_next_free_rec = 1;
+ memset(eb_el->l_recs, 0,
+ sizeof(struct ocfs2_extent_rec) * eb_el->l_count);
+ /*
+ * This actually counts as an empty extent as
+ * c_clusters == 0
+ */
+ eb_el->l_recs[0].e_cpos = new_cpos;
+ eb_el->l_recs[0].e_blkno = next_blkno;
+ /*
+ * eb_el isn't always an interior node, but even leaf
+ * nodes want a zero'd flags and reserved field so
+ * this gets the whole 32 bits regardless of use.
+ */
+ eb_el->l_recs[0].e_int_clusters = 0;
+
+ if (!eb_el->l_tree_depth)
+ new_last_eb_blk = eb->h_blkno;
+
+ next_blkno = eb->h_blkno;
+ }
+
+ /* Link the new branch into the rest of the tree (el will
+ * either be on the fe, or the extent block passed in.
+ */
+ i = el->l_next_free_rec;
+ el->l_recs[i].e_blkno = next_blkno;
+ el->l_recs[i].e_cpos = new_cpos;
+ el->l_recs[i].e_int_clusters = 0;
+ el->l_next_free_rec++;
+
+ /* fe needs a new last extent block pointer, as does the
+ * next_leaf on the previously last-extent-block.
+ */
+ fe->i_last_eb_blk = new_last_eb_blk;
+
+ /* here all the extent block and the new inode information should be
+ * written back to the disk.
+ */
+ for(i = 0; i < new_blocks; i++) {
+ buf = new_eb_bufs[i];
+ ret = ocfs2_write_extent_block(fs, new_blknos[i], buf);
+ if (ret)
+ goto bail;
+ }
+
+ /* update last_eb_buf's next_leaf pointer for
+ * the new last extent block.
+ */
+ eb = (struct ocfs2_extent_block *)(*last_eb_buf);
+ eb->h_next_leaf_blk = new_last_eb_blk;
+ ret = ocfs2_write_extent_block(fs, eb->h_blkno, *last_eb_buf);
+ if (ret)
+ goto bail;
+
+ if (eb_buf) {
+ eb = (struct ocfs2_extent_block *)eb_buf;
+ ret = ocfs2_write_extent_block(fs, eb->h_blkno, eb_buf);
+ if (ret)
+ goto bail;
+ }
+
+ /*
+ * Some callers want to track the rightmost leaf so pass it
+ * back here.
+ */
+ memcpy(*last_eb_buf, new_eb_bufs[0], fs->fs_blocksize);
+
+ /* The inode information isn't updated since we use duplicated extent
+ * block in the insertion and it may fail in other steps.
+ */
+ ret = 0;
+bail:
+ if (new_eb_bufs) {
+ for (i = 0; i < new_blocks; i++)
+ if (new_eb_bufs[i])
+ ocfs2_free(&new_eb_bufs[i]);
+ ocfs2_free(&new_eb_bufs);
+ }
+
+ if (ret && new_blknos)
+ for (i = 0; i < new_blocks; i++)
+ if (new_blknos[i])
+ ocfs2_delete_extent_block(fs, new_blknos[i]);
+
+ if (new_blknos)
+ ocfs2_free(&new_blknos);
+
+ return ret;
+}
+
+/*
+ * Should only be called when there is no space left in any of the
+ * leaf nodes. What we want to do is find the lowest tree depth
+ * non-leaf extent block with room for new records. There are three
+ * valid results of this search:
+ *
+ * 1) a lowest extent block is found, then we pass it back in
+ * *target_buf and return '0'
+ *
+ * 2) the search fails to find anything, but the dinode has room. We
+ * pass NULL back in *target_buf, but still return '0'
+ *
+ * 3) the search fails to find anything AND the dinode is full, in
+ * which case we return > 0
+ *
+ * return status < 0 indicates an error.
+ */
+static errcode_t ocfs2_find_branch_target(ocfs2_filesys *fs,
+ struct ocfs2_dinode *fe,
+ char **target_buf)
+{
+ errcode_t ret = 0;
+ int i;
+ uint64_t blkno;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+ char *buf = NULL, *lowest_buf = NULL;
+
+ *target_buf = NULL;
+
+ el = &fe->id2.i_list;
+
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ return ret;
+
+ while(el->l_tree_depth > 1) {
+ if (el->l_next_free_rec == 0) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto bail;
+ }
+ i = el->l_next_free_rec - 1;
+ blkno = el->l_recs[i].e_blkno;
+ if (!blkno) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto bail;
+ }
+
+ ret = ocfs2_read_extent_block(fs, blkno, buf);
+ if (ret)
+ goto bail;
+
+ eb = (struct ocfs2_extent_block *) buf;
+ el = &eb->h_list;
+
+ if (el->l_next_free_rec < el->l_count)
+ lowest_buf = buf;
+ }
+
+ /* If we didn't find one and the fe doesn't have any room,
+ * then return '1' */
+ if (!lowest_buf
+ && (fe->id2.i_list.l_next_free_rec == fe->id2.i_list.l_count))
+ ret = 1;
+
+ *target_buf = lowest_buf;
+bail:
+ if (buf && !*target_buf)
+ ocfs2_free(&buf);
+
+ return ret;
+}
+
+/*
+ * This function will discard the rightmost extent record.
+ */
+static void ocfs2_shift_records_right(struct ocfs2_extent_list *el)
+{
+ int next_free = el->l_next_free_rec;
+ int count = el->l_count;
+ unsigned int num_bytes;
+
+ assert(next_free);
+ /* This will cause us to go off the end of our extent list. */
+ assert(next_free < count);
+
+ num_bytes = sizeof(struct ocfs2_extent_rec) * next_free;
+
+ memmove(&el->l_recs[1], &el->l_recs[0], num_bytes);
+}
+
+static void ocfs2_rotate_leaf(struct ocfs2_extent_list *el,
+ struct ocfs2_extent_rec *insert_rec)
+{
+ int i, insert_index, next_free, has_empty, num_bytes;
+ uint32_t insert_cpos = insert_rec->e_cpos;
+ struct ocfs2_extent_rec *rec;
+
+ next_free = el->l_next_free_rec;
+ has_empty = ocfs2_is_empty_extent(&el->l_recs[0]);
+
+ assert(next_free);
+
+ /* The tree code before us didn't allow enough room in the leaf. */
+ if (el->l_next_free_rec == el->l_count && !has_empty)
+ assert(0);
+
+ /*
+ * The easiest way to approach this is to just remove the
+ * empty extent and temporarily decrement next_free.
+ */
+ if (has_empty) {
+ /*
+ * If next_free was 1 (only an empty extent), this
+ * loop won't execute, which is fine. We still want
+ * the decrement above to happen.
+ */
+ for(i = 0; i < (next_free - 1); i++)
+ el->l_recs[i] = el->l_recs[i+1];
+
+ next_free--;
+ }
+
+ /* Figure out what the new record index should be. */
+ for(i = 0; i < next_free; i++) {
+ rec = &el->l_recs[i];
+
+ if (insert_cpos < rec->e_cpos)
+ break;
+ }
+ insert_index = i;
+
+ assert(insert_index >= 0);
+ assert(insert_index < el->l_count);
+ assert(insert_index <= next_free);
+
+ /* No need to memmove if we're just adding to the tail. */
+ if (insert_index != next_free) {
+ assert(next_free < el->l_count);
+
+ num_bytes = next_free - insert_index;
+ num_bytes *= sizeof(struct ocfs2_extent_rec);
+ memmove(&el->l_recs[insert_index + 1],
+ &el->l_recs[insert_index],
+ num_bytes);
+ }
+
+ /*
+ * Either we had an empty extent, and need to re-increment or
+ * there was no empty extent on a non full rightmost leaf node,
+ * in which case we still need to increment.
+ */
+ next_free++;
+ el->l_next_free_rec = next_free;
+ /* Make sure none of the math above just messed up our tree. */
+ assert(el->l_next_free_rec <= el->l_count);
+
+ el->l_recs[insert_index] = *insert_rec;
+}
+
+static void ocfs2_remove_empty_extent(struct ocfs2_extent_list *el)
+{
+ int size, num_recs = el->l_next_free_rec;
+
+ assert(num_recs);
+
+ if (ocfs2_is_empty_extent(&el->l_recs[0])) {
+ num_recs--;
+ size = num_recs * sizeof(struct ocfs2_extent_rec);
+ memmove(&el->l_recs[0], &el->l_recs[1], size);
+ memset(&el->l_recs[num_recs], 0,
+ sizeof(struct ocfs2_extent_rec));
+ el->l_next_free_rec = num_recs;
+ }
+}
+
+/*
+ * Create an empty extent record .
+ *
+ * l_next_free_rec may be updated.
+ *
+ * If an empty extent already exists do nothing.
+ */
+static void ocfs2_create_empty_extent(struct ocfs2_extent_list *el)
+{
+ int next_free = el->l_next_free_rec;
+
+ assert(el->l_tree_depth == 0);
+
+ if (next_free == 0)
+ goto set_and_inc;
+
+ if (ocfs2_is_empty_extent(&el->l_recs[0]))
+ return;
+
+ ocfs2_shift_records_right(el);
+
+set_and_inc:
+ el->l_next_free_rec += 1;
+ memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
+}
+
+/*
+ * For a rotation which involves two leaf nodes, the "root node" is
+ * the lowest level tree node which contains a path to both leafs. This
+ * resulting set of information can be used to form a complete "subtree"
+ *
+ * This function is passed two full paths from the dinode down to a
+ * pair of adjacent leaves. It's task is to figure out which path
+ * index contains the subtree root - this can be the root index itself
+ * in a worst-case rotation.
+ *
+ * The array index of the subtree root is passed back.
+ */
+static int ocfs2_find_subtree_root(struct ocfs2_path *left,
+ struct ocfs2_path *right)
+{
+ int i = 0;
+
+ /* Check that the caller passed in two paths from the same tree. */
+ assert(path_root_blkno(left) == path_root_blkno(right));
+
+ do {
+ i++;
+
+ /* The caller didn't pass two adjacent paths. */
+ if (i > left->p_tree_depth)
+ assert(0);
+ } while (left->p_node[i].blkno == right->p_node[i].blkno);
+
+ return i - 1;
+}
+
+typedef errcode_t (path_insert_t)(void *, char *);
+
+/*
+ * Traverse a btree path in search of cpos, starting at root_el.
+ *
+ * This code can be called with a cpos larger than the tree, in which
+ * case it will return the rightmost path.
+ */
+static errcode_t __ocfs2_find_path(ocfs2_filesys *fs,
+ struct ocfs2_extent_list *root_el,
+ uint32_t cpos,
+ path_insert_t *func,
+ void *data)
+{
+ int i, ret = 0;
+ uint32_t range;
+ uint64_t blkno;
+ char *buf = NULL;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_rec *rec;
+
+ el = root_el;
+ while (el->l_tree_depth) {
+ if (el->l_next_free_rec == 0) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+
+ }
+
+
+ for(i = 0; i < el->l_next_free_rec - 1; i++) {
+ rec = &el->l_recs[i];
+
+ /*
+ * In the case that cpos is off the allocation
+ * tree, this should just wind up returning the
+ * rightmost record.
+ */
+ range = rec->e_cpos +
+ ocfs2_rec_clusters(el->l_tree_depth, rec);
+ if (cpos >= rec->e_cpos && cpos < range)
+ break;
+ }
+
+ blkno = el->l_recs[i].e_blkno;
+ if (blkno == 0) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+ }
+
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ return ret;
+
+ ret = ocfs2_read_extent_block(fs, blkno, buf);
+ if (ret)
+ goto out;
+
+ eb = (struct ocfs2_extent_block *) buf;
+ el = &eb->h_list;
+
+ if (el->l_next_free_rec > el->l_count) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+ }
+
+ /* The user's callback must give us the tip for how to
+ * handle the buf we allocated by return values.
+ *
+ * 1) return '0':
+ * the function succeeds,and it will use the buf and
+ * take care of the buffer release.
+ *
+ * 2) return > 0:
+ * the function succeeds, and there is no need for buf,
+ * so we will release it.
+ *
+ * 3) return < 0:
+ * the function fails.
+ */
+ if (func) {
+ ret = func(data, buf);
+
+ if (ret == 0) {
+ buf = NULL;
+ continue;
+ }
+ else if (ret < 0)
+ goto out;
+ }
+ ocfs2_free(&buf);
+ buf = NULL;
+ }
+
+out:
+ /* Catch any trailing buf that the loop didn't handle. */
+ if (buf)
+ ocfs2_free(&buf);
+
+ return ret;
+}
+
+/*
+ * Given an initialized path (that is, it has a valid root extent
+ * list), this function will traverse the btree in search of the path
+ * which would contain cpos.
+ *
+ * The path traveled is recorded in the path structure.
+ *
+ * Note that this will not do any comparisons on leaf node extent
+ * records, so it will work fine in the case that we just added a tree
+ * branch.
+ */
+struct find_path_data {
+ int index;
+ struct ocfs2_path *path;
+};
+
+static errcode_t find_path_ins(void *data, char *eb)
+{
+ struct find_path_data *fp = data;
+
+ ocfs2_path_insert_eb(fp->path, fp->index, eb);
+ fp->index++;
+
+ return 0;
+}
+
+static int ocfs2_find_path(ocfs2_filesys *fs, struct ocfs2_path *path,
+ uint32_t cpos)
+{
+ struct find_path_data data;
+
+ data.index = 1;
+ data.path = path;
+ return __ocfs2_find_path(fs, path_root_el(path), cpos,
+ find_path_ins, &data);
+}
+
+/*
+ * Find the leaf block in the tree which would contain cpos. No
+ * checking of the actual leaf is done.
+ *
+ * This function doesn't handle non btree extent lists.
+ */
+int ocfs2_find_leaf(ocfs2_filesys *fs, struct ocfs2_dinode *di,
+ uint32_t cpos, char **leaf_buf)
+{
+ int ret;
+ char *buf = NULL;
+ struct ocfs2_path *path = NULL;
+ struct ocfs2_extent_list *el = &di->id2.i_list;
+
+ assert(el->l_tree_depth > 0);
+
+ path = ocfs2_new_inode_path(fs, di);
+ if (!path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ ret = ocfs2_find_path(fs, path, cpos);
+ if (ret)
+ goto out;
+
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ goto out;
+
+ memcpy(buf, path_leaf_buf(path), fs->fs_blocksize);
+ *leaf_buf = buf;
+out:
+ ocfs2_free_path(path);
+ return ret;
+}
+
+int ocfs2_xattr_find_leaf(ocfs2_filesys *fs, struct ocfs2_xattr_block *xb,
+ uint32_t cpos, char **leaf_buf)
+{
+ int ret;
+ char *buf = NULL;
+ struct ocfs2_path *path = NULL;
+ struct ocfs2_extent_list *el = &xb->xb_attrs.xb_root.xt_list;
+
+ assert(el->l_tree_depth > 0);
+
+
+ ret = ocfs2_malloc0(sizeof(*path), &path);
+
+ if (!path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ } else {
+ path->p_tree_depth = el->l_tree_depth;
+ path->p_node[0].blkno = xb->xb_blkno;
+ path->p_node[0].buf = (char *)xb;
+ path->p_node[0].el = el;
+ }
+
+ ret = ocfs2_find_path(fs, path, cpos);
+ if (ret)
+ goto out;
+
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ goto out;
+
+ memcpy(buf, path_leaf_buf(path), fs->fs_blocksize);
+ *leaf_buf = buf;
+out:
+ ocfs2_free_path(path);
+ return ret;
+}
+
+/*
+ * Adjust the adjacent records (left_rec, right_rec) involved in a rotation.
+ *
+ * Basically, we've moved stuff around at the bottom of the tree and
+ * we need to fix up the extent records above the changes to reflect
+ * the new changes.
+ *
+ * left_rec: the record on the left.
+ * left_child_el: is the child list pointed to by left_rec
+ * right_rec: the record to the right of left_rec
+ * right_child_el: is the child list pointed to by right_rec
+ *
+ * By definition, this only works on interior nodes.
+ */
+static void ocfs2_adjust_adjacent_records(struct ocfs2_extent_rec *left_rec,
+ struct ocfs2_extent_list *left_child_el,
+ struct ocfs2_extent_rec *right_rec,
+ struct ocfs2_extent_list *right_child_el)
+{
+ uint32_t left_clusters, right_end;
+
+ /*
+ * Interior nodes never have holes. Their cpos is the cpos of
+ * the leftmost record in their child list. Their cluster
+ * count covers the full theoretical range of their child list
+ * - the range between their cpos and the cpos of the record
+ * immediately to their right.
+ */
+ left_clusters = right_child_el->l_recs[0].e_cpos;
+ if (ocfs2_is_empty_extent(&right_child_el->l_recs[0])) {
+ assert(right_child_el->l_next_free_rec > 1);
+ left_clusters = right_child_el->l_recs[1].e_cpos;
+ }
+ left_clusters -= left_rec->e_cpos;
+ left_rec->e_int_clusters = left_clusters;
+
+ /*
+ * Calculate the rightmost cluster count boundary before
+ * moving cpos - we will need to adjust clusters after
+ * updating e_cpos to keep the same highest cluster count.
+ */
+ right_end = right_rec->e_cpos;
+ right_end += right_rec->e_int_clusters;
+
+ right_rec->e_cpos = left_rec->e_cpos;
+ right_rec->e_cpos += left_clusters;
+
+ right_end -= right_rec->e_cpos;
+ right_rec->e_int_clusters = right_end;
+}
+
+/*
+ * Adjust the adjacent root node records involved in a
+ * rotation. left_el_blkno is passed in as a key so that we can easily
+ * find it's index in the root list.
+ */
+static void ocfs2_adjust_root_records(struct ocfs2_extent_list *root_el,
+ struct ocfs2_extent_list *left_el,
+ struct ocfs2_extent_list *right_el,
+ uint64_t left_el_blkno)
+{
+ int i;
+
+ assert(root_el->l_tree_depth > left_el->l_tree_depth);
+
+ for(i = 0; i < root_el->l_next_free_rec - 1; i++) {
+ if (root_el->l_recs[i].e_blkno == left_el_blkno)
+ break;
+ }
+
+ /*
+ * The path walking code should have never returned a root and
+ * two paths which are not adjacent.
+ */
+ assert(i < (root_el->l_next_free_rec - 1));
+
+ ocfs2_adjust_adjacent_records(&root_el->l_recs[i], left_el,
+ &root_el->l_recs[i + 1], right_el);
+}
+
+/*
+ * We've changed a leaf block (in right_path) and need to reflect that
+ * change back up the subtree.
+ *
+ * This happens in multiple places:
+ * - When we've moved an extent record from the left path leaf to the right
+ * path leaf to make room for an empty extent in the left path leaf.
+ * - When our insert into the right path leaf is at the leftmost edge
+ * and requires an update of the path immediately to it's left. This
+ * can occur at the end of some types of rotation and appending inserts.
+ */
+static void ocfs2_complete_edge_insert(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ int subtree_index)
+{
+ int i, idx;
+ uint64_t blkno;
+ struct ocfs2_extent_list *el, *left_el, *right_el;
+ struct ocfs2_extent_rec *left_rec, *right_rec;
+
+ /*
+ * Update the counts and position values within all the
+ * interior nodes to reflect the leaf rotation we just did.
+ *
+ * The root node is handled below the loop.
+ *
+ * We begin the loop with right_el and left_el pointing to the
+ * leaf lists and work our way up.
+ *
+ * NOTE: within this loop, left_el and right_el always refer
+ * to the *child* lists.
+ */
+ left_el = path_leaf_el(left_path);
+ right_el = path_leaf_el(right_path);
+ for(i = left_path->p_tree_depth - 1; i > subtree_index; i--) {
+
+ /*
+ * One nice property of knowing that all of these
+ * nodes are below the root is that we only deal with
+ * the leftmost right node record and the rightmost
+ * left node record.
+ */
+ el = left_path->p_node[i].el;
+ idx = left_el->l_next_free_rec - 1;
+ left_rec = &el->l_recs[idx];
+
+ el = right_path->p_node[i].el;
+ right_rec = &el->l_recs[0];
+
+ ocfs2_adjust_adjacent_records(left_rec, left_el, right_rec,
+ right_el);
+
+ /*
+ * Setup our list pointers now so that the current
+ * parents become children in the next iteration.
+ */
+ left_el = left_path->p_node[i].el;
+ right_el = right_path->p_node[i].el;
+ }
+
+ /*
+ * At the root node, adjust the two adjacent records which
+ * begin our path to the leaves.
+ */
+
+ el = left_path->p_node[subtree_index].el;
+ left_el = left_path->p_node[subtree_index + 1].el;
+ right_el = right_path->p_node[subtree_index + 1].el;
+ blkno = left_path->p_node[subtree_index + 1].blkno;
+
+ ocfs2_adjust_root_records(el, left_el, right_el, blkno);
+
+ /* ocfs2_adjust_root_records only update the extent block in the left
+ * path, and actually right_path->p_node[subtree_index].eb indicates the
+ * same extent block, so we must keep them the same content.
+ */
+ memcpy(right_path->p_node[subtree_index].buf,
+ left_path->p_node[subtree_index].buf, fs->fs_blocksize);
+}
+
+/* Rotate the subtree to right.
+ *
+ * Note: After successful rotation, the extent block will be flashed
+ * to disk accordingly.
+ */
+static errcode_t ocfs2_rotate_subtree_right(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ int subtree_index)
+{
+ errcode_t ret;
+ int i;
+ char *right_leaf_eb;
+ char *left_leaf_eb = NULL;
+ struct ocfs2_extent_list *right_el, *left_el;
+ struct ocfs2_extent_rec move_rec;
+ struct ocfs2_extent_block *eb;
+
+ left_leaf_eb = path_leaf_buf(left_path);
+ eb = (struct ocfs2_extent_block *)left_leaf_eb;
+ left_el = path_leaf_el(left_path);
+
+ if (left_el->l_next_free_rec != left_el->l_count)
+ return OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+
+ /*
+ * This extent block may already have an empty record, so we
+ * return early if so.
+ */
+ if (ocfs2_is_empty_extent(&left_el->l_recs[0]))
+ return 0;
+
+ assert(left_path->p_node[subtree_index].blkno ==
+ right_path->p_node[subtree_index].blkno);
+
+ right_leaf_eb = path_leaf_buf(right_path);
+ right_el = path_leaf_el(right_path);
+
+ ocfs2_create_empty_extent(right_el);
+
+ /* Do the copy now. */
+ i = left_el->l_next_free_rec - 1;
+ move_rec = left_el->l_recs[i];
+ right_el->l_recs[0] = move_rec;
+
+ /*
+ * Clear out the record we just copied and shift everything
+ * over, leaving an empty extent in the left leaf.
+ *
+ * We temporarily subtract from next_free_rec so that the
+ * shift will lose the tail record (which is now defunct).
+ */
+ left_el->l_next_free_rec -= 1;
+ ocfs2_shift_records_right(left_el);
+ memset(&left_el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
+ left_el->l_next_free_rec += 1;
+
+ ocfs2_complete_edge_insert(fs, left_path, right_path, subtree_index);
+
+ ret = ocfs2_sync_path_to_disk(fs, left_path, right_path, subtree_index);
+
+ return ret;
+}
+
+/*
+ * Given a full path, determine what cpos value would return us a path
+ * containing the leaf immediately to the left of the current one.
+ *
+ * Will return zero if the path passed in is already the leftmost path.
+ */
+static int ocfs2_find_cpos_for_left_leaf(struct ocfs2_path *path,
+ uint32_t *cpos)
+{
+ int i, j, ret = 0;
+ uint64_t blkno;
+ struct ocfs2_extent_list *el;
+
+ assert(path->p_tree_depth > 0);
+
+ *cpos = 0;
+
+ blkno = path_leaf_blkno(path);
+
+ /* Start at the tree node just above the leaf and work our way up. */
+ i = path->p_tree_depth - 1;
+ while (i >= 0) {
+ el = path->p_node[i].el;
+
+ /* Find the extent record just before the one in our path. */
+ for(j = 0; j < el->l_next_free_rec; j++) {
+ if (el->l_recs[j].e_blkno == blkno) {
+ if (j == 0) {
+ if (i == 0) {
+ /*
+ * We've determined that the
+ * path specified is already
+ * the leftmost one - return a
+ * cpos of zero.
+ */
+ goto out;
+ }
+ /*
+ * The leftmost record points to our
+ * leaf - we need to travel up the
+ * tree one level.
+ */
+ goto next_node;
+ }
+
+ *cpos = el->l_recs[j - 1].e_cpos;
+ *cpos = *cpos + ocfs2_rec_clusters(
+ el->l_tree_depth,
+ &el->l_recs[j - 1]);
+ *cpos = *cpos - 1;
+ goto out;
+ }
+ }
+
+ /*
+ * If we got here, we never found a valid node where
+ * the tree indicated one should be.
+ */
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+
+next_node:
+ blkno = path->p_node[i].blkno;
+ i--;
+ }
+
+out:
+ return ret;
+}
+
+/*
+ * Trap the case where we're inserting into the theoretical range past
+ * the _actual_ left leaf range. Otherwise, we'll rotate a record
+ * whose cpos is less than ours into the right leaf.
+ *
+ * It's only necessary to look at the rightmost record of the left
+ * leaf because the logic that calls us should ensure that the
+ * theoretical ranges in the path components above the leaves are
+ * correct.
+ */
+static int ocfs2_rotate_requires_path_adjustment(struct ocfs2_path *left_path,
+ uint32_t insert_cpos)
+{
+ struct ocfs2_extent_list *left_el;
+ struct ocfs2_extent_rec *rec;
+ int next_free;
+
+ left_el = path_leaf_el(left_path);
+ next_free = left_el->l_next_free_rec;
+ rec = &left_el->l_recs[next_free - 1];
+
+ if (insert_cpos > rec->e_cpos)
+ return 1;
+ return 0;
+}
+
+static int ocfs2_leftmost_rec_contains(struct ocfs2_extent_list *el,
+ uint32_t cpos)
+{
+ int next_free = el->l_next_free_rec;
+ unsigned int range;
+ struct ocfs2_extent_rec *rec;
+
+ if (next_free == 0)
+ return 0;
+
+ rec = &el->l_recs[0];
+ if (ocfs2_is_empty_extent(rec)) {
+ /* Empty list. */
+ if (next_free == 1)
+ return 0;
+ rec = &el->l_recs[1];
+ }
+
+ range = rec->e_cpos + ocfs2_rec_clusters(el->l_tree_depth, rec);
+ if (cpos >= rec->e_cpos && cpos < range)
+ return 1;
+ return 0;
+}
+
+/*
+ * Rotate all the records in a btree right one record, starting at insert_cpos.
+ *
+ * The path to the rightmost leaf should be passed in.
+ *
+ * The array is assumed to be large enough to hold an entire path (tree depth).
+ *
+ * Upon succesful return from this function:
+ *
+ * - The 'right_path' array will contain a path to the leaf block
+ * whose range contains e_cpos.
+ * - That leaf block will have a single empty extent in list index 0.
+ * - In the case that the rotation requires a post-insert update,
+ * *ret_left_path will contain a valid path which can be passed to
+ * ocfs2_insert_path().
+ */
+static int ocfs2_rotate_tree_right(ocfs2_filesys *fs,
+ enum ocfs2_split_type split,
+ uint32_t insert_cpos,
+ struct ocfs2_path *right_path,
+ struct ocfs2_path **ret_left_path)
+{
+ int ret, start;
+ uint32_t cpos;
+ struct ocfs2_path *left_path = NULL;
+
+ *ret_left_path = NULL;
+
+ left_path = ocfs2_new_path(fs, path_root_buf(right_path),
+ path_root_el(right_path));
+ if (!left_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ ret = ocfs2_find_cpos_for_left_leaf(right_path, &cpos);
+ if (ret)
+ goto out;
+
+ /*
+ * What we want to do here is:
+ *
+ * 1) Start with the rightmost path.
+ *
+ * 2) Determine a path to the leaf block directly to the left
+ * of that leaf.
+ *
+ * 3) Determine the 'subtree root' - the lowest level tree node
+ * which contains a path to both leaves.
+ *
+ * 4) Rotate the subtree.
+ *
+ * 5) Find the next subtree by considering the left path to be
+ * the new right path.
+ *
+ * The check at the top of this while loop also accepts
+ * insert_cpos == cpos because cpos is only a _theoretical_
+ * value to get us the left path - insert_cpos might very well
+ * be filling that hole.
+ *
+ * Stop at a cpos of '0' because we either started at the
+ * leftmost branch (i.e., a tree with one branch and a
+ * rotation inside of it), or we've gone as far as we can in
+ * rotating subtrees.
+ */
+ while (cpos && insert_cpos <= cpos) {
+
+ ret = ocfs2_find_path(fs, left_path, cpos);
+ if (ret)
+ goto out;
+
+ if (path_leaf_blkno(left_path) == path_leaf_blkno(right_path))
+ assert(0);
+
+ if (split == SPLIT_NONE &&
+ ocfs2_rotate_requires_path_adjustment(left_path,
+ insert_cpos)) {
+ /*
+ * We've rotated the tree as much as we
+ * should. The rest is up to
+ * ocfs2_insert_path() to complete, after the
+ * record insertion. We indicate this
+ * situation by returning the left path.
+ *
+ * The reason we don't adjust the records here
+ * before the record insert is that an error
+ * later might break the rule where a parent
+ * record e_cpos will reflect the actual
+ * e_cpos of the 1st nonempty record of the
+ * child list.
+ */
+ *ret_left_path = left_path;
+ goto out_ret_path;
+ }
+
+ start = ocfs2_find_subtree_root(left_path, right_path);
+
+ ret = ocfs2_rotate_subtree_right(fs, left_path, right_path,
+ start);
+ if (ret)
+ goto out;
+
+ if (split != SPLIT_NONE &&
+ ocfs2_leftmost_rec_contains(path_leaf_el(right_path),
+ insert_cpos)) {
+ /*
+ * A rotate moves the rightmost left leaf
+ * record over to the leftmost right leaf
+ * slot. If we're doing an extent split
+ * instead of a real insert, then we have to
+ * check that the extent to be split wasn't
+ * just moved over. If it was, then we can
+ * exit here, passing left_path back -
+ * ocfs2_split_extent() is smart enough to
+ * search both leaves.
+ */
+ *ret_left_path = left_path;
+ goto out_ret_path;
+ }
+ /*
+ * There is no need to re-read the next right path
+ * as we know that it'll be our current left
+ * path. Optimize by copying values instead.
+ */
+ ocfs2_mv_path(right_path, left_path);
+
+ ret = ocfs2_find_cpos_for_left_leaf(right_path, &cpos);
+ if (ret)
+ goto out;
+ }
+
+out:
+ ocfs2_free_path(left_path);
+
+out_ret_path:
+ return ret;
+}
+
+static void ocfs2_update_edge_lengths(struct ocfs2_path *path)
+{
+ int i, idx;
+ struct ocfs2_extent_rec *rec;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_block *eb;
+ uint32_t range;
+
+ /* Path should always be rightmost. */
+ eb = (struct ocfs2_extent_block *)path_leaf_buf(path);
+ assert(eb->h_next_leaf_blk == 0ULL);
+
+ el = &eb->h_list;
+ assert(el->l_next_free_rec > 0);
+ idx = el->l_next_free_rec - 1;
+ rec = &el->l_recs[idx];
+ range = rec->e_cpos + ocfs2_rec_clusters(el->l_tree_depth, rec);
+
+ for (i = 0; i < path->p_tree_depth; i++) {
+ el = path->p_node[i].el;
+ idx = el->l_next_free_rec - 1;
+ rec = &el->l_recs[idx];
+
+ rec->e_int_clusters = range;
+ rec->e_int_clusters -= rec->e_cpos;
+ }
+}
+
+static errcode_t ocfs2_unlink_path(ocfs2_filesys *fs,
+ struct ocfs2_path *path, int unlink_start)
+{
+ int ret, i;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+ char *buf;
+
+ for(i = unlink_start; i < path_num_items(path); i++) {
+ buf = path->p_node[i].buf;
+
+ eb = (struct ocfs2_extent_block *)buf;
+ /*
+ * Not all nodes might have had their final count
+ * decremented by the caller - handle this here.
+ */
+ el = &eb->h_list;
+ assert(el->l_next_free_rec <= 1);
+
+ el->l_next_free_rec = 0;
+ memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
+ ret = ocfs2_delete_extent_block(fs, path->p_node[i].blkno);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/*
+ * ocfs2_unlink_subtree will delete extent blocks in the "right_path"
+ * from "subtree_index".
+ */
+static errcode_t ocfs2_unlink_subtree(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ int subtree_index)
+{
+ errcode_t ret;
+ int i;
+ struct ocfs2_extent_list *root_el = left_path->p_node[subtree_index].el;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_block *eb;
+
+ el = path_leaf_el(left_path);
+
+ eb = (struct ocfs2_extent_block *)right_path->p_node[subtree_index + 1].buf;
+
+ for(i = 1; i < root_el->l_next_free_rec; i++)
+ if (root_el->l_recs[i].e_blkno == eb->h_blkno)
+ break;
+
+ assert(i < root_el->l_next_free_rec);
+
+ memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
+ root_el->l_next_free_rec -= 1;
+
+ eb = (struct ocfs2_extent_block *)path_leaf_buf(left_path);
+ eb->h_next_leaf_blk = 0;
+
+ ret = ocfs2_unlink_path(fs, right_path, subtree_index + 1);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int ocfs2_rotate_subtree_left(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ int subtree_index,
+ int *deleted)
+{
+ errcode_t ret;
+ int i, del_right_subtree = 0, right_has_empty = 0;
+ char *root_buf, *di_buf = path_root_buf(right_path);
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_buf;
+ struct ocfs2_extent_list *right_leaf_el, *left_leaf_el;
+ struct ocfs2_extent_block *eb;
+
+ *deleted = 0;
+
+ right_leaf_el = path_leaf_el(right_path);
+ left_leaf_el = path_leaf_el(left_path);
+ root_buf = left_path->p_node[subtree_index].buf;
+ assert(left_path->p_node[subtree_index].blkno ==
+ right_path->p_node[subtree_index].blkno);
+
+ if (!ocfs2_is_empty_extent(&left_leaf_el->l_recs[0]))
+ return 0;
+
+ eb = (struct ocfs2_extent_block *)path_leaf_buf(right_path);
+ if (ocfs2_is_empty_extent(&right_leaf_el->l_recs[0])) {
+ /*
+ * It's legal for us to proceed if the right leaf is
+ * the rightmost one and it has an empty extent. There
+ * are two cases to handle - whether the leaf will be
+ * empty after removal or not. If the leaf isn't empty
+ * then just remove the empty extent up front. The
+ * next block will handle empty leaves by flagging
+ * them for unlink.
+ *
+ * Non rightmost leaves will throw EAGAIN and the
+ * caller can manually move the subtree and retry.
+ */
+
+ if (eb->h_next_leaf_blk != 0ULL)
+ return EAGAIN;
+
+ if (right_leaf_el->l_next_free_rec > 1) {
+ ocfs2_remove_empty_extent(right_leaf_el);
+ } else
+ right_has_empty = 1;
+ }
+
+ if (eb->h_next_leaf_blk == 0ULL &&
+ right_leaf_el->l_next_free_rec == 1) {
+ /*
+ * We have to update i_last_eb_blk during the meta
+ * data delete.
+ */
+ del_right_subtree = 1;
+ }
+
+ /*
+ * Getting here with an empty extent in the right path implies
+ * that it's the rightmost path and will be deleted.
+ */
+ assert(!right_has_empty || del_right_subtree);
+
+ if (!right_has_empty) {
+ /*
+ * Only do this if we're moving a real
+ * record. Otherwise, the action is delayed until
+ * after removal of the right path in which case we
+ * can do a simple shift to remove the empty extent.
+ */
+ ocfs2_rotate_leaf(left_leaf_el, &right_leaf_el->l_recs[0]);
+ memset(&right_leaf_el->l_recs[0], 0,
+ sizeof(struct ocfs2_extent_rec));
+ }
+ if (eb->h_next_leaf_blk == 0ULL) {
+ /*
+ * Move recs over to get rid of empty extent, decrease
+ * next_free. This is allowed to remove the last
+ * extent in our leaf (setting l_next_free_rec to
+ * zero) - the delete code below won't care.
+ */
+ ocfs2_remove_empty_extent(right_leaf_el);
+ }
+
+ if (del_right_subtree) {
+ ocfs2_unlink_subtree(fs, left_path, right_path, subtree_index);
+ ocfs2_update_edge_lengths(left_path);
+
+ /*
+ * Now the good extent block information is stored in left_path, so
+ * synchronize the right path with it.
+ */
+ for (i = 0; i <= subtree_index; i++)
+ memcpy(right_path->p_node[i].buf,
+ left_path->p_node[i].buf,
+ fs->fs_blocksize);
+
+ eb = (struct ocfs2_extent_block *)path_leaf_buf(left_path);
+ di->i_last_eb_blk = eb->h_blkno;
+
+ /*
+ * Removal of the extent in the left leaf was skipped
+ * above so we could delete the right path
+ * 1st.
+ */
+ if (right_has_empty)
+ ocfs2_remove_empty_extent(left_leaf_el);
+
+ *deleted = 1;
+
+ /*
+ * The extent block in the right path belwo subtree_index
+ * have been deleted, so we don't need to synchronize
+ * them to the disk.
+ */
+ ret = ocfs2_sync_path_to_disk(fs, left_path, NULL,
+ subtree_index);
+ } else {
+ ocfs2_complete_edge_insert(fs, left_path, right_path,
+ subtree_index);
+
+ ret = ocfs2_sync_path_to_disk(fs, left_path, right_path,
+ subtree_index);
+ }
+
+ return ret;
+}
+
+/*
+ * Given a full path, determine what cpos value would return us a path
+ * containing the leaf immediately to the right of the current one.
+ *
+ * Will return zero if the path passed in is already the rightmost path.
+ *
+ * This looks similar, but is subtly different to
+ * ocfs2_find_cpos_for_left_leaf().
+ */
+static int ocfs2_find_cpos_for_right_leaf(ocfs2_filesys *fs,
+ struct ocfs2_path *path,
+ uint32_t *cpos)
+{
+ int i, j, ret = 0;
+ uint64_t blkno;
+ struct ocfs2_extent_list *el;
+
+ *cpos = 0;
+
+ if (path->p_tree_depth == 0)
+ return 0;
+
+ blkno = path_leaf_blkno(path);
+
+ /* Start at the tree node just above the leaf and work our way up. */
+ i = path->p_tree_depth - 1;
+ while (i >= 0) {
+ int next_free;
+
+ el = path->p_node[i].el;
+
+ /*
+ * Find the extent record just after the one in our
+ * path.
+ */
+ next_free = el->l_next_free_rec;
+ for(j = 0; j < el->l_next_free_rec; j++) {
+ if (el->l_recs[j].e_blkno == blkno) {
+ if (j == (next_free - 1)) {
+ if (i == 0) {
+ /*
+ * We've determined that the
+ * path specified is already
+ * the rightmost one - return a
+ * cpos of zero.
+ */
+ goto out;
+ }
+ /*
+ * The rightmost record points to our
+ * leaf - we need to travel up the
+ * tree one level.
+ */
+ goto next_node;
+ }
+
+ *cpos = el->l_recs[j + 1].e_cpos;
+ goto out;
+ }
+ }
+
+ /*
+ * If we got here, we never found a valid node where
+ * the tree indicated one should be.
+ */
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+
+next_node:
+ blkno = path->p_node[i].blkno;
+ i--;
+ }
+
+out:
+ return ret;
+}
+
+static void ocfs2_rotate_rightmost_leaf_left(ocfs2_filesys *fs,
+ struct ocfs2_extent_list *el)
+{
+ if (!ocfs2_is_empty_extent(&el->l_recs[0]))
+ return;
+
+ ocfs2_remove_empty_extent(el);
+
+ return;
+}
+
+static int __ocfs2_rotate_tree_left(ocfs2_filesys *fs,
+ struct ocfs2_path *path,
+ struct ocfs2_path **empty_extent_path)
+{
+ int i, ret, subtree_root, deleted;
+ uint32_t right_cpos;
+ struct ocfs2_path *left_path = NULL;
+ struct ocfs2_path *right_path = NULL;
+
+ assert(ocfs2_is_empty_extent(&(path_leaf_el(path)->l_recs[0])));
+
+ *empty_extent_path = NULL;
+
+ ret = ocfs2_find_cpos_for_right_leaf(fs, path, &right_cpos);
+ if (ret)
+ goto out;
+
+ left_path = ocfs2_new_path(fs, path_root_buf(path),
+ path_root_el(path));
+ if (!left_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ ocfs2_cp_path(fs, left_path, path);
+
+ right_path = ocfs2_new_path(fs, path_root_buf(path),
+ path_root_el(path));
+ if (!right_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ while (right_cpos) {
+ ret = ocfs2_find_path(fs, right_path, right_cpos);
+ if (ret)
+ goto out;
+
+ subtree_root = ocfs2_find_subtree_root(left_path,
+ right_path);
+
+ ret = ocfs2_rotate_subtree_left(fs, left_path,
+ right_path, subtree_root,
+ &deleted);
+ if (ret == EAGAIN) {
+ /*
+ * The rotation has to temporarily stop due to
+ * the right subtree having an empty
+ * extent. Pass it back to the caller for a
+ * fixup.
+ */
+ *empty_extent_path = right_path;
+ right_path = NULL;
+ goto out;
+ }
+ if (ret)
+ goto out;
+
+ /*
+ * The subtree rotate might have removed records on
+ * the rightmost edge. If so, then rotation is
+ * complete.
+ */
+ if (deleted)
+ break;
+
+ ocfs2_mv_path(left_path, right_path);
+
+ ret = ocfs2_find_cpos_for_right_leaf(fs, left_path,
+ &right_cpos);
+ if (ret)
+ goto out;
+ }
+
+out:
+ ocfs2_free_path(right_path);
+ ocfs2_free_path(left_path);
+
+ /*
+ * the path's information is changed during the process of rotation,
+ * so re-read them.
+ */
+ for (i = 1; i <= path->p_tree_depth; i++) {
+ ret = ocfs2_read_extent_block(fs, path->p_node[i].blkno,
+ path->p_node[i].buf);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static int ocfs2_remove_rightmost_path(ocfs2_filesys *fs,
+ struct ocfs2_path *path)
+{
+ int ret, subtree_index, i;
+ uint32_t cpos;
+ struct ocfs2_path *left_path = NULL;
+ struct ocfs2_dinode *di;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+
+ /*
+ * XXX: This code assumes that the root is an inode, which is
+ * true for now but may change as tree code gets generic.
+ */
+ di = (struct ocfs2_dinode *)path_root_buf(path);
+
+ ret = ocfs2_find_cpos_for_left_leaf(path, &cpos);
+ if (ret)
+ goto out;
+
+ if (cpos) {
+ /*
+ * We have a path to the left of this one - it needs
+ * an update too.
+ */
+ left_path = ocfs2_new_path(fs, path_root_buf(path),
+ path_root_el(path));
+ if (!left_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ ret = ocfs2_find_path(fs, left_path, cpos);
+ if (ret)
+ goto out;
+
+ subtree_index = ocfs2_find_subtree_root(left_path, path);
+
+ ocfs2_unlink_subtree(fs, left_path, path,
+ subtree_index);
+ ocfs2_update_edge_lengths(left_path);
+
+ /*
+ * Now the good extent block information is stored in left_path, so
+ * synchronize the right path with it.
+ */
+ for (i = 0; i <= subtree_index; i++)
+ memcpy(path->p_node[i].buf,
+ left_path->p_node[i].buf,
+ fs->fs_blocksize);
+ ret = ocfs2_sync_path_to_disk(fs, left_path,
+ NULL, subtree_index);
+ if (ret)
+ goto out;
+
+ eb = (struct ocfs2_extent_block *)path_leaf_buf(left_path);
+ di->i_last_eb_blk = eb->h_blkno;
+ } else {
+ /*
+ * 'path' is also the leftmost path which
+ * means it must be the only one. This gets
+ * handled differently because we want to
+ * revert the inode back to having extents
+ * in-line.
+ */
+ ocfs2_unlink_path(fs, path, 1);
+
+ el = &di->id2.i_list;
+ el->l_tree_depth = 0;
+ el->l_next_free_rec = 0;
+ memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
+
+ di->i_last_eb_blk = 0;
+ }
+
+out:
+ ocfs2_free_path(left_path);
+ return ret;
+}
+
+/*
+ * Left rotation of btree records.
+ *
+ * In many ways, this is (unsurprisingly) the opposite of right
+ * rotation. We start at some non-rightmost path containing an empty
+ * extent in the leaf block. The code works its way to the rightmost
+ * path by rotating records to the left in every subtree.
+ *
+ * This is used by any code which reduces the number of extent records
+ * in a leaf. After removal, an empty record should be placed in the
+ * leftmost list position.
+ *
+ * This won't handle a length update of the rightmost path records if
+ * the rightmost tree leaf record is removed so the caller is
+ * responsible for detecting and correcting that.
+ */
+static int ocfs2_rotate_tree_left(ocfs2_filesys *fs, struct ocfs2_path *path)
+{
+ int ret = 0;
+ struct ocfs2_path *tmp_path = NULL, *restart_path = NULL;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+
+ el = path_leaf_el(path);
+ if (!ocfs2_is_empty_extent(&el->l_recs[0]))
+ return 0;
+
+ if (path->p_tree_depth == 0) {
+rightmost_no_delete:
+ /*
+ * In-inode extents. This is trivially handled, so do
+ * it up front.
+ */
+ ocfs2_rotate_rightmost_leaf_left(fs,
+ path_leaf_el(path));
+
+ /* we have to synchronize the modified extent block to disk. */
+ if (path->p_tree_depth > 0) {
+ ret = ocfs2_write_extent_block(fs,
+ path_leaf_blkno(path),
+ path_leaf_buf(path));
+ }
+
+ goto out;
+ }
+
+ /*
+ * Handle rightmost branch now. There's several cases:
+ * 1) simple rotation leaving records in there. That's trivial.
+ * 2) rotation requiring a branch delete - there's no more
+ * records left. Two cases of this:
+ * a) There are branches to the left.
+ * b) This is also the leftmost (the only) branch.
+ *
+ * 1) is handled via ocfs2_rotate_rightmost_leaf_left()
+ * 2a) we need the left branch so that we can update it with the unlink
+ * 2b) we need to bring the inode back to inline extents.
+ */
+
+ eb = (struct ocfs2_extent_block *)path_leaf_buf(path);
+ el = &eb->h_list;
+ if (eb->h_next_leaf_blk == 0) {
+ /*
+ * This gets a bit tricky if we're going to delete the
+ * rightmost path. Get the other cases out of the way
+ * 1st.
+ */
+ if (el->l_next_free_rec > 1)
+ goto rightmost_no_delete;
+
+ if (el->l_next_free_rec == 0) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+ }
+
+ /*
+ * XXX: The caller can not trust "path" any more after
+ * this as it will have been deleted. What do we do?
+ *
+ * In theory the rotate-for-merge code will never get
+ * here because it'll always ask for a rotate in a
+ * nonempty list.
+ */
+
+ ret = ocfs2_remove_rightmost_path(fs, path);
+ goto out;
+ }
+
+ /*
+ * Now we can loop, remembering the path we get from EAGAIN
+ * and restarting from there.
+ */
+try_rotate:
+ ret = __ocfs2_rotate_tree_left(fs, path, &restart_path);
+ if (ret && ret != EAGAIN) {
+ goto out;
+ }
+
+ while (ret == EAGAIN) {
+ tmp_path = restart_path;
+ restart_path = NULL;
+
+ ret = __ocfs2_rotate_tree_left(fs, tmp_path, &restart_path);
+ if (ret && ret != EAGAIN) {
+ goto out;
+ }
+
+ ocfs2_free_path(tmp_path);
+ tmp_path = NULL;
+
+ if (ret == 0)
+ goto try_rotate;
+ }
+
+out:
+ ocfs2_free_path(tmp_path);
+ ocfs2_free_path(restart_path);
+ return ret;
+}
+
+static void ocfs2_cleanup_merge(struct ocfs2_extent_list *el,
+ int index)
+{
+ struct ocfs2_extent_rec *rec = &el->l_recs[index];
+ unsigned int size;
+
+ if (rec->e_leaf_clusters == 0) {
+ /*
+ * We consumed all of the merged-from record. An empty
+ * extent cannot exist anywhere but the 1st array
+ * position, so move things over if the merged-from
+ * record doesn't occupy that position.
+ *
+ * This creates a new empty extent so the caller
+ * should be smart enough to have removed any existing
+ * ones.
+ */
+ if (index > 0) {
+ assert(!ocfs2_is_empty_extent(&el->l_recs[0]));
+ size = index * sizeof(struct ocfs2_extent_rec);
+ memmove(&el->l_recs[1], &el->l_recs[0], size);
+ }
+
+ /*
+ * Always memset - the caller doesn't check whether it
+ * created an empty extent, so there could be junk in
+ * the other fields.
+ */
+ memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
+ }
+}
+
+/*
+ * Remove split_rec clusters from the record at index and merge them
+ * onto the beginning of the record at index + 1.
+ */
+static int ocfs2_merge_rec_right(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *split_rec,
+ struct ocfs2_extent_list *el, int index)
+{
+ unsigned int split_clusters = split_rec->e_leaf_clusters;
+ struct ocfs2_extent_rec *left_rec;
+ struct ocfs2_extent_rec *right_rec;
+
+ assert(index < el->l_next_free_rec);
+
+ left_rec = &el->l_recs[index];
+ right_rec = &el->l_recs[index + 1];
+
+ left_rec->e_leaf_clusters -= split_clusters;
+
+ right_rec->e_cpos -= split_clusters;
+ right_rec->e_blkno -=
+ ocfs2_clusters_to_blocks(fs, split_clusters);
+ right_rec->e_leaf_clusters += split_clusters;
+
+ ocfs2_cleanup_merge(el, index);
+
+ return 0;
+}
+
+/*
+ * Remove split_rec clusters from the record at index and merge them
+ * onto the tail of the record at index - 1.
+ */
+static int ocfs2_merge_rec_left(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *split_rec,
+ struct ocfs2_extent_list *el, int index)
+{
+ int has_empty_extent = 0;
+ unsigned int split_clusters = split_rec->e_leaf_clusters;
+ struct ocfs2_extent_rec *left_rec;
+ struct ocfs2_extent_rec *right_rec;
+
+ assert(index > 0);
+
+ left_rec = &el->l_recs[index - 1];
+ right_rec = &el->l_recs[index];
+ if (ocfs2_is_empty_extent(&el->l_recs[0]))
+ has_empty_extent = 1;
+
+ if (has_empty_extent && index == 1) {
+ /*
+ * The easy case - we can just plop the record right in.
+ */
+ *left_rec = *split_rec;
+
+ has_empty_extent = 0;
+ } else {
+ left_rec->e_leaf_clusters += split_clusters;
+ }
+
+ right_rec->e_cpos += split_clusters;
+ right_rec->e_blkno +=
+ ocfs2_clusters_to_blocks(fs, split_clusters);
+ right_rec->e_leaf_clusters -= split_clusters;
+
+ ocfs2_cleanup_merge(el, index);
+
+ return 0;
+}
+
+static int ocfs2_try_to_merge_extent(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ int split_index,
+ struct ocfs2_extent_rec *split_rec,
+ struct ocfs2_merge_ctxt *ctxt)
+
+{
+ int ret = 0;
+ struct ocfs2_extent_list *el = path_leaf_el(left_path);
+ struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
+
+ assert(ctxt->c_contig_type != CONTIG_NONE);
+
+ if (ctxt->c_split_covers_rec && ctxt->c_has_empty_extent) {
+ /*
+ * The merge code will need to create an empty
+ * extent to take the place of the newly
+ * emptied slot. Remove any pre-existing empty
+ * extents - having more than one in a leaf is
+ * illegal.
+ */
+ ret = ocfs2_rotate_tree_left(fs, left_path);
+ if (ret)
+ goto out;
+
+ split_index--;
+ rec = &el->l_recs[split_index];
+ }
+
+ if (ctxt->c_contig_type == CONTIG_LEFTRIGHT) {
+ /*
+ * Left-right contig implies this.
+ */
+ assert(ctxt->c_split_covers_rec);
+ assert(split_index != 0);
+
+ /*
+ * Since the leftright insert always covers the entire
+ * extent, this call will delete the insert record
+ * entirely, resulting in an empty extent record added to
+ * the extent block.
+ *
+ * Since the adding of an empty extent shifts
+ * everything back to the right, there's no need to
+ * update split_index here.
+ */
+ ret = ocfs2_merge_rec_left(fs, split_rec, el, split_index);
+ if (ret)
+ goto out;
+
+ /*
+ * We can only get this from logic error above.
+ */
+ assert(ocfs2_is_empty_extent(&el->l_recs[0]));
+
+ /*
+ * The left merge left us with an empty extent, remove
+ * it.
+ */
+ ret = ocfs2_rotate_tree_left(fs, left_path);
+ if (ret)
+ goto out;
+
+ split_index--;
+ rec = &el->l_recs[split_index];
+
+ /*
+ * Note that we don't pass split_rec here on purpose -
+ * we've merged it into the left side.
+ */
+ ret = ocfs2_merge_rec_right(fs, rec, el, split_index);
+ if (ret)
+ goto out;
+
+ assert(ocfs2_is_empty_extent(&el->l_recs[0]));
+
+ ret = ocfs2_rotate_tree_left(fs, left_path);
+ /*
+ * Error from this last rotate is not critical, so
+ * don't bubble it up.
+ */
+ ret = 0;
+ } else {
+ /*
+ * Merge a record to the left or right.
+ *
+ * 'contig_type' is relative to the existing record,
+ * so for example, if we're "right contig", it's to
+ * the record on the left (hence the left merge).
+ */
+ if (ctxt->c_contig_type == CONTIG_RIGHT) {
+ ret = ocfs2_merge_rec_left(fs,
+ split_rec, el,
+ split_index);
+ if (ret)
+ goto out;
+ } else {
+ ret = ocfs2_merge_rec_right(fs,
+ split_rec, el,
+ split_index);
+ if (ret)
+ goto out;
+ }
+
+ /* we have to synchronize the modified extent block to disk. */
+ if (left_path->p_tree_depth > 0) {
+ ret = ocfs2_write_extent_block(fs,
+ path_leaf_blkno(left_path),
+ path_leaf_buf(left_path));
+ if (ret)
+ goto out;
+ }
+
+ if (ctxt->c_split_covers_rec) {
+ /*
+ * The merge may have left an empty extent in
+ * our leaf. Try to rotate it away.
+ */
+ ret = ocfs2_rotate_tree_left(fs,left_path);
+ ret = 0;
+ }
+ }
+
+out:
+ return ret;
+}
+
+static void ocfs2_subtract_from_rec(ocfs2_filesys *fs,
+ enum ocfs2_split_type split,
+ struct ocfs2_extent_rec *rec,
+ struct ocfs2_extent_rec *split_rec)
+{
+ uint64_t len_blocks;
+
+ len_blocks = ocfs2_clusters_to_blocks(fs, split_rec->e_leaf_clusters);
+
+ if (split == SPLIT_LEFT) {
+ /*
+ * Region is on the left edge of the existing
+ * record.
+ */
+ rec->e_cpos += split_rec->e_leaf_clusters;
+ rec->e_blkno += len_blocks;
+ rec->e_leaf_clusters -= split_rec->e_leaf_clusters;
+ } else {
+ /*
+ * Region is on the right edge of the existing
+ * record.
+ */
+ rec->e_leaf_clusters -= split_rec->e_leaf_clusters;
+ }
+}
+
+/*
+ * Change the depth of the tree. That means allocating an extent block,
+ * copying all extent records from the dinode into the extent block,
+ * and then pointing the dinode to the new extent_block.
+ */
+static errcode_t shift_tree_depth(ocfs2_filesys *fs,
+ struct ocfs2_dinode *di,
+ char **new_eb)
+{
+ errcode_t ret;
+ char *buf = NULL;
+ uint64_t blkno;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+ uint32_t new_clusters;
+
+ el = &di->id2.i_list;
+ if (el->l_next_free_rec != el->l_count)
+ return OCFS2_ET_INTERNAL_FAILURE;
+
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ return ret;
+
+ ret = ocfs2_new_extent_block(fs, &blkno);
+ if (ret)
+ goto out;
+
+ ret = ocfs2_read_extent_block(fs, blkno, buf);
+ if (ret)
+ goto out;
+
+ eb = (struct ocfs2_extent_block *)buf;
+ eb->h_list.l_tree_depth = el->l_tree_depth;
+ eb->h_list.l_next_free_rec = el->l_next_free_rec;
+ memcpy(eb->h_list.l_recs, el->l_recs,
+ sizeof(struct ocfs2_extent_rec) * el->l_count);
+
+ new_clusters = ocfs2_sum_rightmost_rec(&eb->h_list);
+
+ el->l_tree_depth++;
+ memset(el->l_recs, 0,
+ sizeof(struct ocfs2_extent_rec) * el->l_count);
+ el->l_recs[0].e_cpos = 0;
+ el->l_recs[0].e_blkno = blkno;
+ el->l_recs[0].e_int_clusters = new_clusters;
+ el->l_next_free_rec = 1;
+
+ if (el->l_tree_depth == 1)
+ di->i_last_eb_blk = blkno;
+
+ ret = ocfs2_write_extent_block(fs, blkno, buf);
+ if (!ret)
+ *new_eb = buf;
+out:
+ if (buf && !*new_eb)
+ ocfs2_free(&buf);
+
+ return ret;
+}
+
+static enum ocfs2_contig_type
+ocfs2_figure_merge_contig_type(ocfs2_filesys *fs,
+ struct ocfs2_extent_list *el, int index,
+ struct ocfs2_extent_rec *split_rec)
+{
+ struct ocfs2_extent_rec *rec;
+ enum ocfs2_contig_type ret = CONTIG_NONE;
+
+ /*
+ * We're careful to check for an empty extent record here -
+ * the merge code will know what to do if it sees one.
+ */
+
+ if (index > 0) {
+ rec = &el->l_recs[index - 1];
+ if (index == 1 && ocfs2_is_empty_extent(rec)) {
+ if (split_rec->e_cpos == el->l_recs[index].e_cpos)
+ ret = CONTIG_RIGHT;
+ } else {
+ ret = ocfs2_extent_contig(fs, rec, split_rec);
+ }
+ }
+
+ if (index < el->l_next_free_rec - 1) {
+ enum ocfs2_contig_type contig_type;
+
+ rec = &el->l_recs[index + 1];
+ contig_type = ocfs2_extent_contig(fs, rec, split_rec);
+
+ if (contig_type == CONTIG_LEFT && ret == CONTIG_RIGHT)
+ ret = CONTIG_LEFTRIGHT;
+ else if (ret == CONTIG_NONE)
+ ret = contig_type;
+ }
+
+ return ret;
+}
+
+static void ocfs2_figure_contig_type(ocfs2_filesys *fs,
+ struct ocfs2_insert_type *insert,
+ struct ocfs2_extent_list *el,
+ struct ocfs2_extent_rec *insert_rec)
+{
+ int i;
+ enum ocfs2_contig_type contig_type = CONTIG_NONE;
+
+ assert(el->l_tree_depth == 0);
+
+ for(i = 0; i < el->l_next_free_rec; i++) {
+ contig_type = ocfs2_extent_contig(fs, &el->l_recs[i],
+ insert_rec);
+ if (contig_type != CONTIG_NONE) {
+ insert->ins_contig_index = i;
+ break;
+ }
+ }
+ insert->ins_contig = contig_type;
+}
+
+/*
+ * This should only be called against the righmost leaf extent list.
+ *
+ * ocfs2_figure_appending_type() will figure out whether we'll have to
+ * insert at the tail of the rightmost leaf.
+ *
+ * This should also work against the dinode list for tree's with 0
+ * depth. If we consider the dinode list to be the rightmost leaf node
+ * then the logic here makes sense.
+ */
+static void ocfs2_figure_appending_type(struct ocfs2_insert_type *insert,
+ struct ocfs2_extent_list *el,
+ struct ocfs2_extent_rec *insert_rec)
+{
+ int i;
+ uint32_t cpos = insert_rec->e_cpos;
+ struct ocfs2_extent_rec *rec;
+
+ insert->ins_appending = APPEND_NONE;
+
+ assert(el->l_tree_depth == 0);
+
+ if (!el->l_next_free_rec)
+ goto set_tail_append;
+
+ if (ocfs2_is_empty_extent(&el->l_recs[0])) {
+ /* Were all records empty? */
+ if (el->l_next_free_rec == 1)
+ goto set_tail_append;
+ }
+
+ i = el->l_next_free_rec - 1;
+ rec = &el->l_recs[i];
+
+ if (cpos >= (rec->e_cpos + rec->e_leaf_clusters))
+ goto set_tail_append;
+
+ return;
+
+set_tail_append:
+ insert->ins_appending = APPEND_TAIL;
+}
+
+/*
+ * Helper function called at the begining of an insert.
+ *
+ * This computes a few things that are commonly used in the process of
+ * inserting into the btree:
+ * - Whether the new extent is contiguous with an existing one.
+ * - The current tree depth.
+ * - Whether the insert is an appending one.
+ * - The total # of free records in the tree.
+ *
+ * All of the information is stored on the ocfs2_insert_type
+ * structure.
+ */
+static int ocfs2_figure_insert_type(struct insert_ctxt *ctxt,
+ char **last_eb_buf,
+ int *free_records,
+ struct ocfs2_insert_type *insert)
+{
+ int ret;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_dinode *di = ctxt->di;
+ struct ocfs2_extent_rec *insert_rec = &ctxt->rec;
+ ocfs2_filesys *fs = ctxt->fs;
+ struct ocfs2_path *path = NULL;
+ char *buf = *last_eb_buf;
+
+ insert->ins_split = SPLIT_NONE;
+
+ el = &di->id2.i_list;
+ insert->ins_tree_depth = el->l_tree_depth;
+
+ if (el->l_tree_depth) {
+ /*
+ * If we have tree depth, we read in the
+ * rightmost extent block ahead of time as
+ * ocfs2_figure_insert_type() and ocfs2_add_branch()
+ * may want it later.
+ */
+ assert(buf);
+ ret = ocfs2_read_extent_block(fs, di->i_last_eb_blk, buf);
+ if (ret)
+ goto out;
+
+ eb = (struct ocfs2_extent_block *) buf;
+ el = &eb->h_list;
+ }
+ /*
+ * Unless we have a contiguous insert, we'll need to know if
+ * there is room left in our allocation tree for another
+ * extent record.
+ *
+ * XXX: This test is simplistic, we can search for empty
+ * extent records too.
+ */
+ *free_records = el->l_count - el->l_next_free_rec;
+
+ if (!insert->ins_tree_depth) {
+ ocfs2_figure_contig_type(fs, insert, el, insert_rec);
+ ocfs2_figure_appending_type(insert, el, insert_rec);
+ return 0;
+ }
+
+ path = ocfs2_new_inode_path(fs, di);
+ if (!path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+ /*
+ * In the case that we're inserting past what the tree
+ * currently accounts for, ocf2_find_path() will return for
+ * us the rightmost tree path. This is accounted for below in
+ * the appending code.
+ */
+ ret = ocfs2_find_path(fs, path, insert_rec->e_cpos);
+ if (ret)
+ goto out;
+
+ el = path_leaf_el(path);
+
+ /*
+ * Now that we have the path, there's two things we want to determine:
+ * 1) Contiguousness (also set contig_index if this is so)
+ *
+ * 2) Are we doing an append? We can trivially break this up
+ * into two types of appends: simple record append, or a
+ * rotate inside the tail leaf.
+ */
+ ocfs2_figure_contig_type(fs, insert, el, insert_rec);
+
+ /*
+ * The insert code isn't quite ready to deal with all cases of
+ * left contiguousness. Specifically, if it's an insert into
+ * the 1st record in a leaf, it will require the adjustment of
+ * e_clusters on the last record of the path directly to it's
+ * left. For now, just catch that case and fool the layers
+ * above us. This works just fine for tree_depth == 0, which
+ * is why we allow that above.
+ */
+ if (insert->ins_contig == CONTIG_LEFT &&
+ insert->ins_contig_index == 0)
+ insert->ins_contig = CONTIG_NONE;
+
+ /*
+ * Ok, so we can simply compare against last_eb to figure out
+ * whether the path doesn't exist. This will only happen in
+ * the case that we're doing a tail append, so maybe we can
+ * take advantage of that information somehow.
+ */
+ if (di->i_last_eb_blk == path_leaf_blkno(path)) {
+ /*
+ * Ok, ocfs2_find_path() returned us the rightmost
+ * tree path. This might be an appending insert. There are
+ * two cases:
+ * 1) We're doing a true append at the tail:
+ * -This might even be off the end of the leaf
+ * 2) We're "appending" by rotating in the tail
+ */
+ ocfs2_figure_appending_type(insert, el, insert_rec);
+ }
+
+out:
+ ocfs2_free_path(path);
+
+ return ret;
+}
+
+/*
+ * Do the final bits of extent record insertion at the target leaf
+ * list. If this leaf is part of an allocation tree, it is assumed
+ * that the tree above has been prepared.
+ */
+static void ocfs2_insert_at_leaf(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *insert_rec,
+ struct ocfs2_extent_list *el,
+ struct ocfs2_insert_type *insert)
+{
+ int i = insert->ins_contig_index;
+ unsigned int range;
+ struct ocfs2_extent_rec *rec;
+
+ assert(el->l_tree_depth == 0);
+
+ if (insert->ins_split != SPLIT_NONE) {
+ i = ocfs2_search_extent_list(el, insert_rec->e_cpos);
+ assert(i != -1);
+ rec = &el->l_recs[i];
+ ocfs2_subtract_from_rec(fs, insert->ins_split, rec,
+ insert_rec);
+ goto rotate;
+ }
+
+ /*
+ * Contiguous insert - either left or right.
+ */
+ if (insert->ins_contig != CONTIG_NONE) {
+ rec = &el->l_recs[i];
+ if (insert->ins_contig == CONTIG_LEFT) {
+ rec->e_blkno = insert_rec->e_blkno;
+ rec->e_cpos = insert_rec->e_cpos;
+ }
+ rec->e_leaf_clusters += insert_rec->e_leaf_clusters;
+ return;
+ }
+
+ /*
+ * Handle insert into an empty leaf.
+ */
+ if (el->l_next_free_rec == 0 ||
+ (el->l_next_free_rec == 1 &&
+ ocfs2_is_empty_extent(&el->l_recs[0]))) {
+ el->l_recs[0] = *insert_rec;
+ el->l_next_free_rec = 1;
+ return;
+ }
+
+ /*
+ * Appending insert.
+ */
+ if (insert->ins_appending == APPEND_TAIL) {
+ i = el->l_next_free_rec - 1;
+ rec = &el->l_recs[i];
+ range = rec->e_cpos + rec->e_leaf_clusters;
+ assert(insert_rec->e_cpos >= range);
+
+ i++;
+ el->l_recs[i] = *insert_rec;
+ el->l_next_free_rec += 1;
+ return;
+ }
+
+rotate:
+ /*
+ * Ok, we have to rotate.
+ *
+ * At this point, it is safe to assume that inserting into an
+ * empty leaf and appending to a leaf have both been handled
+ * above.
+ *
+ * This leaf needs to have space, either by the empty 1st
+ * extent record, or by virtue of an l_next_rec < l_count.
+ */
+ ocfs2_rotate_leaf(el, insert_rec);
+}
+
+static int ocfs2_adjust_rightmost_records(ocfs2_filesys *fs,
+ struct ocfs2_path *path,
+ struct ocfs2_extent_rec *insert_rec)
+{
+ int i, next_free;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_rec *rec;
+
+ /*
+ * Update everything except the leaf block.
+ */
+ for (i = 0; i < path->p_tree_depth; i++) {
+ el = path->p_node[i].el;
+
+ next_free = el->l_next_free_rec;
+ if (next_free == 0)
+ return OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+
+ rec = &el->l_recs[next_free - 1];
+
+ rec->e_int_clusters = insert_rec->e_cpos;
+ rec->e_int_clusters += insert_rec->e_leaf_clusters;
+ rec->e_int_clusters -= rec->e_cpos;
+ }
+
+ return 0;
+}
+
+static int ocfs2_append_rec_to_path(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *insert_rec,
+ struct ocfs2_path *right_path,
+ struct ocfs2_path **ret_left_path)
+{
+ int ret, next_free;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_path *left_path = NULL;
+
+ *ret_left_path = NULL;
+
+ /*
+ * This shouldn't happen for non-trees. The extent rec cluster
+ * count manipulation below only works for interior nodes.
+ */
+ assert(right_path->p_tree_depth > 0);
+
+ /*
+ * If our appending insert is at the leftmost edge of a leaf,
+ * then we might need to update the rightmost records of the
+ * neighboring path.
+ */
+
+ el = path_leaf_el(right_path);
+ next_free = el->l_next_free_rec;
+ if (next_free == 0 ||
+ (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0]))) {
+ uint32_t left_cpos;
+
+ ret = ocfs2_find_cpos_for_left_leaf(right_path, &left_cpos);
+ if (ret)
+ goto out;
+ /*
+ * No need to worry if the append is already in the
+ * leftmost leaf.
+ */
+ if (left_cpos) {
+ left_path = ocfs2_new_path(fs,
+ path_root_buf(right_path),
+ path_root_el(right_path));
+ if (!left_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ ret = ocfs2_find_path(fs, left_path, left_cpos);
+ if (ret)
+ goto out;
+ }
+ }
+
+ ret = ocfs2_adjust_rightmost_records(fs, right_path, insert_rec);
+ if (ret)
+ goto out;
+
+ *ret_left_path = left_path;
+ ret = 0;
+out:
+ if (ret)
+ ocfs2_free_path(left_path);
+ return ret;
+}
+
+static void ocfs2_split_record(ocfs2_filesys *fs,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ struct ocfs2_extent_rec *split_rec,
+ enum ocfs2_split_type split)
+{
+ int index;
+ uint32_t cpos = split_rec->e_cpos;
+ struct ocfs2_extent_list *left_el = NULL, *right_el, *insert_el, *el;
+ struct ocfs2_extent_rec *rec, *tmprec;
+
+ right_el = path_leaf_el(right_path);;
+ if (left_path)
+ left_el = path_leaf_el(left_path);
+
+ el = right_el;
+ insert_el = right_el;
+ index = ocfs2_search_extent_list(el, cpos);
+ if (index != -1) {
+ if (index == 0 && left_path) {
+ assert(!ocfs2_is_empty_extent(&el->l_recs[0]));
+
+ /*
+ * This typically means that the record
+ * started in the left path but moved to the
+ * right as a result of rotation. We either
+ * move the existing record to the left, or we
+ * do the later insert there.
+ *
+ * In this case, the left path should always
+ * exist as the rotate code will have passed
+ * it back for a post-insert update.
+ */
+
+ if (split == SPLIT_LEFT) {
+ /*
+ * It's a left split. Since we know
+ * that the rotate code gave us an
+ * empty extent in the left path, we
+ * can just do the insert there.
+ */
+ insert_el = left_el;
+ } else {
+ /*
+ * Right split - we have to move the
+ * existing record over to the left
+ * leaf. The insert will be into the
+ * newly created empty extent in the
+ * right leaf.
+ */
+ tmprec = &right_el->l_recs[index];
+ ocfs2_rotate_leaf(left_el, tmprec);
+ el = left_el;
+
+ memset(tmprec, 0, sizeof(*tmprec));
+ index = ocfs2_search_extent_list(left_el, cpos);
+ assert(index != -1);
+ }
+ }
+ } else {
+ assert(left_path);
+ assert(ocfs2_is_empty_extent(&left_el->l_recs[0]));
+ /*
+ * Left path is easy - we can just allow the insert to
+ * happen.
+ */
+ el = left_el;
+ insert_el = left_el;
+ index = ocfs2_search_extent_list(el, cpos);
+ assert(index != -1);
+ }
+
+ rec = &el->l_recs[index];
+ ocfs2_subtract_from_rec(fs, split, rec, split_rec);
+ ocfs2_rotate_leaf(insert_el, split_rec);
+}
+
+/*
+ * This function only does inserts on an allocation b-tree. For dinode
+ * lists, ocfs2_insert_at_leaf() is called directly.
+ *
+ * right_path is the path we want to do the actual insert
+ * in. left_path should only be passed in if we need to update that
+ * portion of the tree after an edge insert.
+ */
+static int ocfs2_insert_path(struct insert_ctxt* ctxt,
+ struct ocfs2_path *left_path,
+ struct ocfs2_path *right_path,
+ struct ocfs2_extent_rec *insert_rec,
+ struct ocfs2_insert_type *insert)
+{
+ int ret, subtree_index;
+
+ if (insert->ins_split != SPLIT_NONE) {
+ /*
+ * We could call ocfs2_insert_at_leaf() for some types
+ * of splits, but it's easier to just let one seperate
+ * function sort it all out.
+ */
+ ocfs2_split_record(ctxt->fs, left_path, right_path,
+ insert_rec, insert->ins_split);
+ } else
+ ocfs2_insert_at_leaf(ctxt->fs, insert_rec, path_leaf_el(right_path),
+ insert);
+
+ if (left_path) {
+ /*
+ * The rotate code has indicated that we need to fix
+ * up portions of the tree after the insert.
+ */
+ subtree_index = ocfs2_find_subtree_root(left_path, right_path);
+ ocfs2_complete_edge_insert(ctxt->fs, left_path,
+ right_path, subtree_index);
+ } else
+ subtree_index = 0;
+
+ ret = ocfs2_sync_path_to_disk(ctxt->fs, left_path,
+ right_path, subtree_index);
+ if (ret)
+ goto out;
+
+ ret = 0;
+out:
+ return ret;
+}
+
+static int ocfs2_do_insert_extent(struct insert_ctxt* ctxt,
+ struct ocfs2_insert_type *type)
+{
+ int ret, rotate = 0;
+ uint32_t cpos;
+ struct ocfs2_path *right_path = NULL;
+ struct ocfs2_path *left_path = NULL;
+ struct ocfs2_extent_rec *insert_rec = &ctxt->rec;
+ ocfs2_filesys *fs = ctxt->fs;
+ struct ocfs2_dinode *di = ctxt->di;
+ struct ocfs2_extent_list *el = &di->id2.i_list;
+
+ if (el->l_tree_depth == 0) {
+ ocfs2_insert_at_leaf(fs, insert_rec, el, type);
+ goto out_update_clusters;
+ }
+
+ right_path = ocfs2_new_inode_path(fs, di);
+ if (!right_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ /*
+ * Determine the path to start with. Rotations need the
+ * rightmost path, everything else can go directly to the
+ * target leaf.
+ */
+ cpos = insert_rec->e_cpos;
+ if (type->ins_appending == APPEND_NONE &&
+ type->ins_contig == CONTIG_NONE) {
+ rotate = 1;
+ cpos = UINT_MAX;
+ }
+
+ ret = ocfs2_find_path(fs, right_path, cpos);
+ if (ret)
+ goto out;
+
+ /*
+ * Rotations and appends need special treatment - they modify
+ * parts of the tree's above them.
+ *
+ * Both might pass back a path immediate to the left of the
+ * one being inserted to. This will be cause
+ * ocfs2_insert_path() to modify the rightmost records of
+ * left_path to account for an edge insert.
+ *
+ * XXX: When modifying this code, keep in mind that an insert
+ * can wind up skipping both of these two special cases...
+ */
+
+ if (rotate) {
+ ret = ocfs2_rotate_tree_right(fs, type->ins_split,
+ insert_rec->e_cpos,
+ right_path, &left_path);
+ if (ret)
+ goto out;
+ } else if (type->ins_appending == APPEND_TAIL
+ && type->ins_contig != CONTIG_LEFT) {
+ ret = ocfs2_append_rec_to_path(fs, insert_rec,
+ right_path, &left_path);
+ if (ret)
+ goto out;
+ }
+
+ ret = ocfs2_insert_path(ctxt, left_path, right_path, insert_rec, type);
+ if (ret)
+ goto out;
+
+out_update_clusters:
+ if (type->ins_split == SPLIT_NONE)
+ di->i_clusters += insert_rec->e_leaf_clusters;
+ ret = 0;
+
+out:
+ ocfs2_free_path(left_path);
+ ocfs2_free_path(right_path);
+
+ return ret;
+}
+
+struct duplicate_ctxt {
+ struct ocfs2_dinode *di;
+ uint64_t next_leaf_blk;
+};
+
+static errcode_t duplicate_extent_block(ocfs2_filesys *fs,
+ struct ocfs2_extent_list *old_el,
+ struct ocfs2_extent_list *new_el,
+ struct duplicate_ctxt *ctxt)
+{
+ int i;
+ errcode_t ret;
+ uint64_t blkno, new_blkno;
+ struct ocfs2_extent_rec *rec = NULL;
+ char *eb_buf = NULL, *new_eb_buf = NULL;
+ struct ocfs2_extent_block *eb = NULL;
+ struct ocfs2_extent_list *child_old_el = NULL, *child_new_el = NULL;
+
+ assert (old_el->l_tree_depth > 0);
+
+ /* empty the whole extent list at first. */
+ *new_el = *old_el;
+ new_el->l_next_free_rec = 0;
+ memset(new_el->l_recs, 0,
+ sizeof(struct ocfs2_extent_rec) * new_el->l_count);
+
+ if (old_el->l_next_free_rec == 0) {
+ /* XXX:
+ * We have a tree depth > 0 and no extent record in it,
+ * should it be a corrupted block?
+ */
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto bail;
+ }
+
+ ret = ocfs2_malloc_block(fs->fs_io, &eb_buf);
+ if (ret)
+ goto bail;
+ ret = ocfs2_malloc_block(fs->fs_io, &new_eb_buf);
+ if (ret)
+ goto bail;
+
+ /* we iterate the extent list from the last one for recording
+ * the next_leaf_blk for the previous leaf.
+ */
+ for (i = old_el->l_next_free_rec - 1; i >= 0; i--) {
+ rec = &old_el->l_recs[i];
+
+ if (!ocfs2_rec_clusters(old_el->l_tree_depth, rec))
+ continue;
+
+ blkno = rec->e_blkno;
+ ret = ocfs2_read_extent_block(fs, blkno, eb_buf);
+ if (ret)
+ goto bail;
+
+ /* First make the new_buf the same as the old buf. */
+ memcpy(new_eb_buf, eb_buf, fs->fs_blocksize);
+
+ eb = (struct ocfs2_extent_block *)eb_buf;
+ child_old_el = &eb->h_list;
+ eb = (struct ocfs2_extent_block *)new_eb_buf;
+ child_new_el = &eb->h_list;
+
+ if (child_old_el->l_tree_depth > 0) {
+ /* the extent record in our list still has child extent
+ * block, so we have to iterate it.
+ */
+ ret = duplicate_extent_block(fs,
+ child_old_el,
+ child_new_el,
+ ctxt);
+ if (ret)
+ goto bail;
+ }
+
+ /* now we allocate a new extent block and save it. */
+ ret = ocfs2_new_extent_block(fs, &new_blkno);
+ if (ret)
+ goto bail;
+
+ eb = (struct ocfs2_extent_block *)new_eb_buf;
+ eb->h_blkno = new_blkno;
+ if (child_old_el->l_tree_depth == 0) {
+ /*
+ * This is the leaf blkno, we have to set its
+ * h_next_leaf_blk and then record itself for
+ * future use.
+ */
+ eb->h_next_leaf_blk = ctxt->next_leaf_blk;
+ ctxt->next_leaf_blk = new_blkno;
+ }
+
+ ret = ocfs2_write_extent_block(fs, new_blkno, new_eb_buf);
+ if (ret)
+ goto bail;
+
+ memcpy(&new_el->l_recs[i], rec, sizeof(struct ocfs2_extent_rec));
+ new_el->l_recs[i].e_blkno = new_blkno;
+
+ eb = (struct ocfs2_extent_block *)new_eb_buf;
+ /* set the new i_last_eb_blk in the new dinode. */
+ if (ctxt->di->i_last_eb_blk == blkno)
+ ctxt->di->i_last_eb_blk = new_blkno;
+ }
+
+ new_el->l_next_free_rec = old_el->l_next_free_rec;
+ ret = 0;
+
+bail:
+ if (eb_buf)
+ ocfs2_free(&eb_buf);
+ if (new_eb_buf)
+ ocfs2_free(&new_eb_buf);
+ /* Free all the extent block we allocate. */
+ if (ret) {
+ for (i = 0; i < old_el->l_next_free_rec; i++) {
+ rec = &new_el->l_recs[i];
+ if (rec->e_blkno)
+ ocfs2_delete_extent_block(fs, rec->e_blkno);
+ }
+ }
+
+ return ret;
+}
+
+static errcode_t duplicate_extent_block_dinode(ocfs2_filesys *fs,
+ char *old_buf, char *new_buf)
+{
+ errcode_t ret = 0;
+ struct ocfs2_dinode *old_di = NULL, *new_di = NULL;
+ struct ocfs2_extent_list *old_el = NULL, *new_el = NULL;
+ struct duplicate_ctxt ctxt;
+
+ old_di = (struct ocfs2_dinode *)old_buf;
+ old_el = &old_di->id2.i_list;
+ new_di = (struct ocfs2_dinode *)new_buf;
+ new_el = &new_di->id2.i_list;
+
+ assert(old_el->l_tree_depth > 0);
+
+ /* empty the whole extent list at first. */
+ *new_el = *old_el;
+ memset(new_el->l_recs, 0,
+ sizeof(struct ocfs2_extent_rec) * new_el->l_count);
+ new_el->l_next_free_rec = 0;
+
+ memset(&ctxt, 0, sizeof(ctxt));
+ ctxt.di = new_di;
+ ctxt.next_leaf_blk = 0;
+ ret = duplicate_extent_block(fs, old_el, new_el, &ctxt);
+
+ return ret;
+}
+
+static void free_duplicated_extent_block(ocfs2_filesys *fs,
+ struct ocfs2_extent_list *el)
+{
+ int i;
+ errcode_t ret;
+ char *buf = NULL;
+ struct ocfs2_extent_rec *rec;
+ struct ocfs2_extent_list *child_el;
+ struct ocfs2_extent_block *eb;
+
+ assert(el->l_tree_depth > 0);
+
+ ret = ocfs2_malloc_block(fs->fs_io, &buf);
+ if (ret)
+ return;
+
+ for (i = 0; i < el->l_next_free_rec; i ++) {
+ rec = &el->l_recs[i];
+
+ if (!ocfs2_rec_clusters(el->l_tree_depth, rec))
+ continue;
+
+ ret = ocfs2_read_extent_block(fs, rec->e_blkno, buf);
+ if (ret)
+ continue;
+
+ eb = (struct ocfs2_extent_block *)buf;
+ child_el = &eb->h_list;
+ if (child_el->l_tree_depth > 0)
+ free_duplicated_extent_block(fs, child_el);
+
+ ocfs2_delete_extent_block(fs, rec->e_blkno);
+ }
+
+ if(buf)
+ ocfs2_free(&buf);
+}
+
+static void free_duplicated_extent_block_dinode(ocfs2_filesys *fs,
+ char *di_buf)
+{
+ struct ocfs2_dinode *di = NULL;
+ struct ocfs2_extent_list *el = NULL;
+
+ di = (struct ocfs2_dinode *)di_buf;
+ el = &di->id2.i_list;
+
+ assert(el->l_tree_depth > 0);
+
+ free_duplicated_extent_block(fs, el);
+}
+
+/*
+ * Grow a b-tree so that it has more records.
+ *
+ * We might shift the tree depth in which case existing paths should
+ * be considered invalid.
+ *
+ * Tree depth after the grow is returned via *final_depth.
+ *
+ * *last_eb will be updated by ocfs2_add_branch().
+ */
+static int ocfs2_grow_tree(ocfs2_filesys *fs, struct ocfs2_dinode *di,
+ int *final_depth, char **last_eb)
+{
+ errcode_t ret;
+ char *eb_buf = NULL;
+ int shift;
+ int depth = di->id2.i_list.l_tree_depth;
+
+ shift = ocfs2_find_branch_target(fs, di, &eb_buf);
+ if (shift < 0) {
+ ret = shift;
+ goto out;
+ }
+
+ /* We traveled all the way to the bottom of the allocation tree
+ * and didn't find room for any more extents - we need to add
+ * another tree level */
+ if (shift) {
+
+ /* shift_tree_depth will return us a buffer with
+ * the new extent block (so we can pass that to
+ * ocfs2_add_branch). */
+ ret = shift_tree_depth(fs, di, &eb_buf);
+ if (ret)
+ goto out;
+
+ depth++;
+ if (depth == 1) {
+ /*
+ * Special case: we have room now if we shifted from
+ * tree_depth 0, so no more work needs to be done.
+ *
+ * We won't be calling add_branch, so pass
+ * back *last_eb as the new leaf.
+ */
+ assert(*last_eb);
+ memcpy(*last_eb, eb_buf, fs->fs_blocksize);
+ goto out;
+ }
+ }
+
+ /* call ocfs2_add_branch to add the final part of the tree with
+ * the new data. */
+ ret = ocfs2_add_branch(fs, di, eb_buf, last_eb);
+
+out:
+ if (final_depth)
+ *final_depth = depth;
+ return ret;
+}
+
+/*
+ * Insert an extent into an inode btree.
+ */
+errcode_t ocfs2_insert_extent(ocfs2_filesys *fs, uint64_t ino, uint32_t cpos,
+ uint64_t c_blkno, uint32_t clusters,
+ uint16_t flag)
+{
+ errcode_t ret;
+ ocfs2_cached_inode *ci = NULL;
+
+ ret = ocfs2_read_cached_inode(fs, ino, &ci);
+ if (ret)
+ goto bail;
+
+ ret = ocfs2_cached_inode_insert_extent(ci, cpos, c_blkno,
+ clusters, flag);
+ if (ret)
+ goto bail;
+
+ ret = ocfs2_write_cached_inode(fs, ci);
+
+bail:
+ if (ci)
+ ocfs2_free_cached_inode(fs, ci);
+
+ return ret;
+}
+
+errcode_t ocfs2_cached_inode_insert_extent(ocfs2_cached_inode *ci,
+ uint32_t cpos, uint64_t c_blkno,
+ uint32_t clusters, uint16_t flag)
+{
+ errcode_t ret;
+ struct insert_ctxt ctxt;
+ struct ocfs2_insert_type insert = {0, };
+ char *last_eb = NULL;
+ char *backup_buf = NULL;
+ char *di_buf = NULL;
+ int free_records = 0;
+ ocfs2_filesys *fs = ci->ci_fs;
+
+ ctxt.fs = fs;
+ ctxt.di = ci->ci_inode;
+ di_buf = (char *)ctxt.di;
+
+ /* In order to orderize the written block sequence and avoid
+ * the corruption for the inode, we duplicate the extent block
+ * here and do the insertion in the duplicated ones.
+ *
+ * Note: we only do this in case the file has extent blocks.
+ * And if the duplicate process fails, we should go on the normal
+ * insert process.
+ */
+ if (ctxt.di->id2.i_list.l_tree_depth) {
+ ret = ocfs2_malloc_block(fs->fs_io, &backup_buf);
+ if (ret)
+ goto bail;
+
+ memcpy(backup_buf, di_buf, fs->fs_blocksize);
+
+ /* duplicate the extent block. If it succeeds, di_buf
+ * will point to the new allocated extent blocks, and
+ * the following insertion will happens to the new ones.
+ */
+ ret = duplicate_extent_block_dinode(fs, backup_buf, di_buf);
+ if (ret) {
+ memcpy(di_buf, backup_buf,fs->fs_blocksize);
+ ocfs2_free(&backup_buf);
+ backup_buf = NULL;
+ }
+ }
+
+ memset(&ctxt.rec, 0, sizeof(struct ocfs2_extent_rec));
+ ctxt.rec.e_cpos = cpos;
+ ctxt.rec.e_blkno = c_blkno;
+ ctxt.rec.e_leaf_clusters = clusters;
+ ctxt.rec.e_flags = flag;
+
+ ret = ocfs2_malloc_block(fs->fs_io, &last_eb);
+ if (ret)
+ return ret;
+
+ ret = ocfs2_figure_insert_type(&ctxt, &last_eb, &free_records, &insert);
+ if (ret)
+ goto bail;
+
+ if (insert.ins_contig == CONTIG_NONE && free_records == 0) {
+ ret = ocfs2_grow_tree(fs, ctxt.di,
+ &insert.ins_tree_depth, &last_eb);
+ if (ret)
+ goto bail;
+ }
+
+ /* Finally, we can add clusters. This might rotate the tree for us. */
+ ret = ocfs2_do_insert_extent(&ctxt, &insert);
+ if (ret)
+ goto bail;
+
+bail:
+ if (backup_buf) {
+ /* we have duplicated the extent block during the insertion.
+ * so if it succeeds, we should free the old ones, and if fails,
+ * the duplicate ones should be freed.
+ */
+ if (ret)
+ free_duplicated_extent_block_dinode(fs, di_buf);
+ else
+ free_duplicated_extent_block_dinode(fs, backup_buf);
+ ocfs2_free(&backup_buf);
+ }
+
+ if (last_eb)
+ ocfs2_free(&last_eb);
+
+ return ret;
+}
+
+static void ocfs2_make_right_split_rec(ocfs2_filesys *fs,
+ struct ocfs2_extent_rec *split_rec,
+ uint32_t cpos,
+ struct ocfs2_extent_rec *rec)
+{
+ uint32_t rec_cpos = rec->e_cpos;
+ uint32_t rec_range = rec_cpos + rec->e_leaf_clusters;
+
+ memset(split_rec, 0, sizeof(struct ocfs2_extent_rec));
+
+ split_rec->e_cpos = cpos;
+ split_rec->e_leaf_clusters = rec_range - cpos;
+
+ split_rec->e_blkno = rec->e_blkno;
+ split_rec->e_blkno += ocfs2_clusters_to_blocks(fs, cpos - rec_cpos);
+
+ split_rec->e_flags = rec->e_flags;
+}
+
+static int ocfs2_split_and_insert(struct insert_ctxt *ctxt,
+ struct ocfs2_path *path,
+ char **last_eb_buf,
+ int split_index,
+ struct ocfs2_extent_rec *orig_split_rec)
+{
+ int ret = 0, depth;
+ unsigned int insert_range, rec_range, do_leftright = 0;
+ struct ocfs2_extent_rec tmprec;
+ struct ocfs2_extent_list *rightmost_el;
+ struct ocfs2_extent_rec rec;
+ struct ocfs2_insert_type insert;
+ struct ocfs2_extent_block *eb;
+
+leftright:
+ /*
+ * Store a copy of the record on the stack - it might move
+ * around as the tree is manipulated below.
+ */
+ rec = path_leaf_el(path)->l_recs[split_index];
+
+ rightmost_el = &ctxt->di->id2.i_list;
+
+ depth = rightmost_el->l_tree_depth;
+ if (depth) {
+ assert(*last_eb_buf);
+ eb = (struct ocfs2_extent_block *) (*last_eb_buf);
+ rightmost_el = &eb->h_list;
+ }
+
+ if (rightmost_el->l_next_free_rec == rightmost_el->l_count) {
+ ret = ocfs2_grow_tree(ctxt->fs, ctxt->di, &depth, last_eb_buf);
+ if (ret)
+ goto out;
+ }
+
+ memset(&insert, 0, sizeof(struct ocfs2_insert_type));
+ insert.ins_appending = APPEND_NONE;
+ insert.ins_contig = CONTIG_NONE;
+ insert.ins_tree_depth = depth;
+
+ insert_range = ctxt->rec.e_cpos + ctxt->rec.e_leaf_clusters;
+ rec_range = rec.e_cpos + rec.e_leaf_clusters;
+
+ if (ctxt->rec.e_cpos == rec.e_cpos) {
+ insert.ins_split = SPLIT_LEFT;
+ } else if (insert_range == rec_range) {
+ insert.ins_split = SPLIT_RIGHT;
+ } else {
+ /*
+ * Left/right split. We fake this as a right split
+ * first and then make a second pass as a left split.
+ */
+ insert.ins_split = SPLIT_RIGHT;
+
+ ocfs2_make_right_split_rec(ctxt->fs, &tmprec, insert_range,
+ &rec);
+
+ ctxt->rec = tmprec;
+
+ assert(!do_leftright);
+ do_leftright = 1;
+ }
+
+ ret = ocfs2_do_insert_extent(ctxt, &insert);
+ if (ret)
+ goto out;
+
+ if (do_leftright == 1) {
+ uint32_t cpos;
+ struct ocfs2_extent_list *el;
+
+ do_leftright++;
+ ctxt->rec = *orig_split_rec;
+
+ ocfs2_reinit_path(path, 1);
+
+ cpos = ctxt->rec.e_cpos;
+ ret = ocfs2_find_path(ctxt->fs, path, cpos);
+ if (ret)
+ goto out;
+
+ el = path_leaf_el(path);
+ split_index = ocfs2_search_extent_list(el, cpos);
+ goto leftright;
+ }
+out:
+
+ return ret;
+}
+
+/*
+ * Mark part or all of the extent record at split_index in the leaf
+ * pointed to by path as written. This removes the unwritten
+ * extent flag.
+ *
+ * Care is taken to handle contiguousness so as to not grow the tree.
+ *
+ * last_eb_buf should be the rightmost leaf block for any inode with a
+ * btree. Since a split may grow the tree or a merge might shrink it,
+ * the caller cannot trust the contents of that buffer after this call.
+ *
+ * This code is optimized for readability - several passes might be
+ * made over certain portions of the tree.
+ */
+static int __ocfs2_mark_extent_written(struct insert_ctxt *insert_ctxt,
+ struct ocfs2_path *path,
+ int split_index)
+{
+ int ret = 0;
+ struct ocfs2_extent_rec split_rec = insert_ctxt->rec;
+ struct ocfs2_extent_list *el = path_leaf_el(path);
+ char *last_eb_buf = NULL;
+ struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
+ struct ocfs2_merge_ctxt merge_ctxt;
+ struct ocfs2_extent_list *rightmost_el;
+ ocfs2_filesys *fs = insert_ctxt->fs;
+
+ if (!rec->e_flags & OCFS2_EXT_UNWRITTEN) {
+ ret = OCFS2_ET_INVALID_ARGUMENT;
+ goto out;
+ }
+
+ if (rec->e_cpos > split_rec.e_cpos ||
+ ((rec->e_cpos + rec->e_leaf_clusters) <
+ (split_rec.e_cpos + split_rec.e_leaf_clusters))) {
+ ret = OCFS2_ET_INVALID_ARGUMENT;
+ goto out;
+ }
+
+ merge_ctxt.c_contig_type = ocfs2_figure_merge_contig_type(fs, el,
+ split_index,
+ &split_rec);
+
+ /*
+ * We have to allocate the last_eb_buf no matter the current tree
+ * depth is since we may shift the tree depth from 0 to 1 in
+ * ocfs2_split_and_insert and use last_eb_buf to store.
+ */
+ ret = ocfs2_malloc_block(fs->fs_io, &last_eb_buf);
+ if (ret)
+ goto out;
+ /*
+ * The core merge / split code wants to know how much room is
+ * left in this inodes allocation tree, so we pass the
+ * rightmost extent list.
+ */
+ if (path->p_tree_depth) {
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_dinode *di = insert_ctxt->di;
+
+ ret = ocfs2_read_extent_block(fs,
+ di->i_last_eb_blk,
+ last_eb_buf);
+ if (ret)
+ goto out;
+
+ eb = (struct ocfs2_extent_block *) last_eb_buf;
+
+ rightmost_el = &eb->h_list;
+ } else
+ rightmost_el = path_root_el(path);
+
+ if (rec->e_cpos == split_rec.e_cpos &&
+ rec->e_leaf_clusters == split_rec.e_leaf_clusters)
+ merge_ctxt.c_split_covers_rec = 1;
+ else
+ merge_ctxt.c_split_covers_rec = 0;
+
+ merge_ctxt.c_has_empty_extent = ocfs2_is_empty_extent(&el->l_recs[0]);
+
+ if (merge_ctxt.c_contig_type == CONTIG_NONE) {
+ if (merge_ctxt.c_split_covers_rec)
+ el->l_recs[split_index] = split_rec;
+ else
+ ret = ocfs2_split_and_insert(insert_ctxt, path,
+ &last_eb_buf, split_index,
+ &split_rec);
+ } else {
+ ret = ocfs2_try_to_merge_extent(fs, path,
+ split_index, &split_rec,
+ &merge_ctxt);
+ }
+
+out:
+ if (last_eb_buf)
+ ocfs2_free(&last_eb_buf);
+ return ret;
+}
+
+/*
+ * Mark the already-existing extent at cpos as written for len clusters.
+ *
+ * If the existing extent is larger than the request, initiate a
+ * split. An attempt will be made at merging with adjacent extents.
+ *
+ */
+int ocfs2_mark_extent_written(ocfs2_filesys *fs, struct ocfs2_dinode *di,
+ uint32_t cpos, uint32_t len,
+ uint64_t p_blkno)
+{
+ int ret, index;
+ struct ocfs2_path *left_path = NULL;
+ struct ocfs2_extent_list *el;
+ struct insert_ctxt ctxt;
+ char *backup_buf = NULL, *di_buf = NULL;
+
+ if (!ocfs2_writes_unwritten_extents(OCFS2_RAW_SB(fs->fs_super)))
+ return OCFS2_ET_UNSUPP_FEATURE;
+
+ /* In order to orderize the written block sequence and avoid
+ * the corruption for the inode, we duplicate the extent block
+ * here and do the insertion in the duplicated ones.
+ *
+ * Note: we only do this in case the file has extent blocks.
+ * And if the duplicate process fails, we should go on the normal
+ * insert process.
+ */
+ di_buf = (char *)di;
+ if (di->id2.i_list.l_tree_depth) {
+ ret = ocfs2_malloc_block(fs->fs_io, &backup_buf);
+ if (ret)
+ goto out;
+
+ memcpy(backup_buf, di_buf, fs->fs_blocksize);
+
+ /* duplicate the extent block. If it succeeds, di_buf
+ * will point to the new allocated extent blocks, and
+ * the following insertion will happens to the new ones.
+ */
+ ret = duplicate_extent_block_dinode(fs, backup_buf, di_buf);
+ if (ret) {
+ memcpy(di_buf, backup_buf,fs->fs_blocksize);
+ ocfs2_free(&backup_buf);
+ backup_buf = NULL;
+ }
+ }
+
+ left_path = ocfs2_new_inode_path(fs, di);
+ if (!left_path) {
+ ret = OCFS2_ET_NO_MEMORY;
+ goto out;
+ }
+
+ ret = ocfs2_find_path(fs, left_path, cpos);
+ if (ret)
+ goto out;
+
+ el = path_leaf_el(left_path);
+
+ index = ocfs2_search_extent_list(el, cpos);
+ if (index == -1 || index >= el->l_next_free_rec) {
+ ret = OCFS2_ET_CORRUPT_EXTENT_BLOCK;
+ goto out;
+ }
+
+ ctxt.fs = fs;
+ ctxt.di = di;
+
+ memset(&ctxt.rec, 0, sizeof(struct ocfs2_extent_rec));
+ ctxt.rec.e_cpos = cpos;
+ ctxt.rec.e_leaf_clusters = len;
+ ctxt.rec.e_blkno = p_blkno;
+ ctxt.rec.e_flags = path_leaf_el(left_path)->l_recs[index].e_flags;
+ ctxt.rec.e_flags &= ~OCFS2_EXT_UNWRITTEN;
+
+ ret = __ocfs2_mark_extent_written(&ctxt, left_path, index);
+ if (ret)
+ goto out;
+
+ ret = ocfs2_write_inode(fs, di->i_blkno, di_buf);
+
+out:
+ if (backup_buf) {
+ /* we have duplicated the extent block during the insertion.
+ * so if it succeeds, we should free the old ones, and if fails,
+ * the duplicate ones should be freed.
+ */
+ if (ret)
+ free_duplicated_extent_block_dinode(fs, di_buf);
+ else
+ free_duplicated_extent_block_dinode(fs, backup_buf);
+ ocfs2_free(&backup_buf);
+ }
+ ocfs2_free_path(left_path);
+ return ret;
+}
--
1.5.5
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