[Ocfs2-devel] [PATCH 21/41] ocfs2: Add normal functions for reflink a normal file's extents.
Tao Ma
tao.ma at oracle.com
Mon Aug 17 23:19:22 PDT 2009
2 major functions are added in this patch.
ocfs2_attach_refcount_tree will create a new refcount tree to the
old file if it doesn't have one and insert all the extent records
to the tree if they are not refcounted.
ocfs2_create_reflink_node will:
1. set the refcount tree to the new file.
2. call ocfs2_duplicate_extent_list which will iterate all the
extents for the old file, insert it to the new file and increase
the corresponding referennce count.
Signed-off-by: Tao Ma <tao.ma at oracle.com>
---
fs/ocfs2/refcounttree.c | 286 +++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 286 insertions(+), 0 deletions(-)
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 0231f17..ec07518 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -3139,3 +3139,289 @@ int ocfs2_refcount_cow(struct inode *inode,
out:
return ret;
}
+
+/*
+ * Insert a new extent into refcount tree and mark a extent rec
+ * as refcounted in the dinode tree.
+ */
+int ocfs2_add_refcount_flag(struct inode *inode,
+ struct ocfs2_extent_tree *data_et,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ u32 cpos, u32 p_cluster, u32 num_clusters,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret;
+ handle_t *handle;
+ int credits = 1, ref_blocks = 0;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_alloc_context *meta_ac = NULL;
+
+ ret = ocfs2_calc_refcount_meta_credits(inode->i_sb,
+ ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ &ref_blocks, &credits);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ mlog(0, "reserve new metadata %d, credits = %d\n",
+ ref_blocks, credits);
+
+ if (ref_blocks) {
+ ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb),
+ ref_blocks, &meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_mark_extent_refcounted(inode, data_et, handle,
+ cpos, num_clusters, p_cluster,
+ meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = __ocfs2_increase_refcount(handle, ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ meta_ac, dealloc);
+ if (ret)
+ mlog_errno(ret);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out:
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+ return ret;
+}
+
+static int ocfs2_attach_refcount_tree(struct inode *inode,
+ struct buffer_head *di_bh)
+{
+ int ret;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_refcount_tree *ref_tree;
+ unsigned int ext_flags;
+ loff_t size;
+ u32 cpos, num_clusters, clusters, p_cluster;
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_extent_tree di_et;
+
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ if (!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)) {
+ ret = ocfs2_create_refcount_tree(inode, di_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ BUG_ON(!di->i_refcount_loc);
+ ret = ocfs2_lock_refcount_tree(osb,
+ le64_to_cpu(di->i_refcount_loc), 1,
+ &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ocfs2_init_dinode_extent_tree(&di_et, INODE_CACHE(inode), di_bh);
+
+ size = i_size_read(inode);
+ clusters = ocfs2_clusters_for_bytes(inode->i_sb, size);
+
+ cpos = 0;
+ while (cpos < clusters) {
+ ret = ocfs2_get_clusters(inode, cpos, &p_cluster,
+ &num_clusters, &ext_flags);
+
+ if (p_cluster && !(ext_flags & OCFS2_EXT_REFCOUNTED)) {
+ ret = ocfs2_add_refcount_flag(inode, &di_et,
+ &ref_tree->rf_ci,
+ ref_root_bh, cpos,
+ p_cluster, num_clusters,
+ &dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+ }
+ cpos += num_clusters;
+ }
+
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+
+ if (!ret && ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+out:
+ /*
+ * Empty the extent map so that we may get the right extent
+ * record from the disk.
+ */
+ ocfs2_extent_map_trunc(inode, 0);
+
+ return ret;
+}
+
+static int ocfs2_add_refcounted_extent(struct inode *inode,
+ struct ocfs2_extent_tree *et,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ u32 cpos, u32 p_cluster, u32 num_clusters,
+ unsigned int ext_flags,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret;
+ handle_t *handle;
+ int credits = 0;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_alloc_context *meta_ac = NULL;
+
+ ret = ocfs2_lock_refcount_allocators(inode->i_sb,
+ p_cluster, num_clusters,
+ et, ref_ci,
+ ref_root_bh, &meta_ac,
+ NULL, &credits);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_insert_extent(handle, et, cpos,
+ cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
+ p_cluster)),
+ num_clusters, ext_flags, meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = __ocfs2_increase_refcount(handle, ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ meta_ac, dealloc);
+ if (ret)
+ mlog_errno(ret);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out:
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+ return ret;
+}
+
+static int ocfs2_duplicate_extent_list(struct inode *s_inode,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret = 0;
+ u32 p_cluster, num_clusters, clusters, cpos;
+ loff_t size;
+ unsigned int ext_flags;
+ struct ocfs2_extent_tree et;
+
+ ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(t_inode), t_bh);
+
+ size = i_size_read(s_inode);
+ clusters = ocfs2_clusters_for_bytes(s_inode->i_sb, size);
+
+ cpos = 0;
+ while (cpos < clusters) {
+ ret = ocfs2_get_clusters(s_inode, cpos, &p_cluster,
+ &num_clusters, &ext_flags);
+
+ if (p_cluster) {
+ ret = ocfs2_add_refcounted_extent(t_inode, &et,
+ ref_ci, ref_root_bh,
+ cpos, p_cluster,
+ num_clusters,
+ ext_flags,
+ dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ cpos += num_clusters;
+ }
+
+out:
+ return ret;
+}
+
+static int ocfs2_create_reflink_node(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh)
+{
+ int ret;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_super *osb = OCFS2_SB(s_inode->i_sb);
+ struct ocfs2_refcount_block *rb;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)s_bh->b_data;
+ struct ocfs2_refcount_tree *ref_tree;
+
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ ret = ocfs2_set_refcount_tree(t_inode, t_bh,
+ le64_to_cpu(di->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_lock_refcount_tree(osb, le64_to_cpu(di->i_refcount_loc),
+ 1, &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+
+ ret = ocfs2_duplicate_extent_list(s_inode, t_inode, t_bh,
+ &ref_tree->rf_ci, ref_root_bh,
+ &dealloc);
+ if (ret)
+ mlog_errno(ret);
+
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+out:
+ if (ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+
+ return ret;
+}
--
1.6.2.rc2.16.gf474c
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