[Ocfs2-devel] [PATCH 14/16] Ocfs2/move_extents: move/defrag extents within a certain range.
Tristan Ye
tristan.ye at oracle.com
Thu Mar 17 23:35:41 PDT 2011
he basic logic of moving extents for a file is pretty like punching-hole
sequence, walk the extents within the range as user specified, calculating
an appropriate len to defrag/move, then let ocfs2_defrag/move_extent() to
do the actual moving.
This func ends up setting 'OCFS2_MOVE_EXT_FL_COMPLETE' to userpace if operation
gets done successfully.
Signed-off-by: Tristan Ye <tristan.ye at oracle.com>
---
fs/ocfs2/ioctl.c | 5 +
fs/ocfs2/move_extents.c | 312 +++++++++++++++++++++++++++++++++++++++++++++++
fs/ocfs2/move_extents.h | 2 +
3 files changed, 319 insertions(+), 0 deletions(-)
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index 7a48681..b8fe7a7 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -23,6 +23,7 @@
#include "ioctl.h"
#include "resize.h"
#include "refcounttree.h"
+#include "move_extents.h"
#include <linux/ext2_fs.h>
@@ -523,6 +524,8 @@ long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return -EFAULT;
return ocfs2_info_handle(inode, &info, 0);
+ case OCFS2_IOC_MOVE_EXT:
+ return ocfs2_ioctl_move_extents(filp, (void __user *)arg);
default:
return -ENOTTY;
}
@@ -565,6 +568,8 @@ long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
return -EFAULT;
return ocfs2_info_handle(inode, &info, 1);
+ case OCFS2_IOC_MOVE_EXT:
+ break;
default:
return -ENOIOCTLCMD;
}
diff --git a/fs/ocfs2/move_extents.c b/fs/ocfs2/move_extents.c
index 2d31bad..71c97de 100644
--- a/fs/ocfs2/move_extents.c
+++ b/fs/ocfs2/move_extents.c
@@ -831,3 +831,315 @@ static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
*len_defraged = 0;
}
}
+
+static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
+ struct ocfs2_move_extents_context *context)
+{
+ int ret, flags, do_defrag, skip = 0;
+ u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
+ u32 len_defraged = 0, defrag_thresh, new_phys_cpos = 0;
+
+ struct inode *inode = context->inode;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct ocfs2_move_extents *range = context->range;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ if ((inode->i_size == 0) || (range->me_len == 0))
+ return 0;
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+ return 0;
+
+ context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
+
+ ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
+ ocfs2_init_dealloc_ctxt(&context->dealloc);
+
+ /*
+ * TO-DO XXX:
+ *
+ * - xattr extents.
+ */
+
+ do_defrag = context->auto_defrag;
+
+ /*
+ * extents moving happens in unit of clusters, for the sake
+ * of simplicity, we may ignore two clusters where 'byte_start'
+ * and 'byte_start + len' were within.
+ */
+ move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
+ len_to_move = (range->me_start + range->me_len) >>
+ osb->s_clustersize_bits;
+ if (len_to_move >= move_start)
+ len_to_move -= move_start;
+ else
+ len_to_move = 0;
+
+ if (do_defrag)
+ defrag_thresh = range->me_thresh >> osb->s_clustersize_bits;
+ else
+ new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
+ range->me_goal);
+
+ mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
+ "thresh: %u\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)range->me_start,
+ (unsigned long long)range->me_len,
+ move_start, len_to_move, defrag_thresh);
+
+ cpos = move_start;
+ while (len_to_move) {
+ ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
+ &flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (alloc_size > len_to_move)
+ alloc_size = len_to_move;
+
+ /*
+ * XXX: how to deal with a hole:
+ *
+ * - skip the hole of course
+ * - force a new defragmentation
+ */
+ if (!phys_cpos) {
+ if (do_defrag)
+ len_defraged = 0;
+
+ goto next;
+ }
+
+ if (do_defrag) {
+ ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
+ defrag_thresh, &skip);
+ /*
+ * skip large extents
+ */
+ if (skip) {
+ skip = 0;
+ goto next;
+ }
+
+ mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
+ "alloc_size: %u, len_defraged: %u\n",
+ cpos, phys_cpos, alloc_size, len_defraged);
+
+ ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
+ alloc_size, flags);
+ } else {
+ ret = ocfs2_move_extent(context, cpos, phys_cpos,
+ &new_phys_cpos, alloc_size,
+ flags);
+
+ new_phys_cpos += alloc_size;
+ }
+
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ context->clusters_moved += alloc_size;
+next:
+ cpos += alloc_size;
+ len_to_move -= alloc_size;
+ }
+
+ range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
+
+out:
+ range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
+ context->clusters_moved);
+ range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
+ context->new_phys_cpos);
+
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &context->dealloc);
+
+ return ret;
+}
+
+static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
+{
+ int status;
+ handle_t *handle;
+ struct inode *inode = context->inode;
+ struct ocfs2_dinode *di;
+ struct buffer_head *di_bh = NULL;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ if (!inode)
+ return -ENOENT;
+
+ if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+ return -EROFS;
+
+ mutex_lock(&inode->i_mutex);
+
+ /*
+ * This prevents concurrent writes from other nodes
+ */
+ status = ocfs2_rw_lock(inode, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out;
+ }
+
+ status = ocfs2_inode_lock(inode, &di_bh, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_rw_unlock;
+ }
+
+ /*
+ * rememer ip_xattr_sem also needs to be held if necessary
+ */
+ down_write(&OCFS2_I(inode)->ip_alloc_sem);
+
+ status = __ocfs2_move_extents_range(di_bh, context);
+
+ up_write(&OCFS2_I(inode)->ip_alloc_sem);
+ if (status) {
+ mlog_errno(status);
+ goto out_inode_unlock;
+ }
+
+ /*
+ * We update ctime for these changes
+ */
+ handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ status = PTR_ERR(handle);
+ mlog_errno(status);
+ goto out_inode_unlock;
+ }
+
+ status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (status) {
+ mlog_errno(status);
+ goto out_commit;
+ }
+
+ di = (struct ocfs2_dinode *)di_bh->b_data;
+ inode->i_ctime = CURRENT_TIME;
+ di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
+ di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
+
+ ocfs2_journal_dirty(handle, di_bh);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+
+out_inode_unlock:
+ brelse(di_bh);
+ ocfs2_inode_unlock(inode, 1);
+out_rw_unlock:
+ ocfs2_rw_unlock(inode, 1);
+out:
+ mutex_unlock(&inode->i_mutex);
+
+ return status;
+}
+
+int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
+{
+ int status;
+
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct ocfs2_move_extents range;
+ struct ocfs2_move_extents_context *context = NULL;
+
+ status = mnt_want_write(filp->f_path.mnt);
+ if (status)
+ return status;
+
+ status = -EINVAL;
+
+ if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE))
+ goto out;
+
+ if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
+ status = -EPERM;
+ goto out;
+ }
+
+ context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
+ if (!context) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto out;
+ }
+
+ context->inode = inode;
+ context->file = filp;
+
+ if (!argp) {
+ memset(&range, 0, sizeof(range));
+ range.me_len = (u64)-1;
+ range.me_flags |= OCFS2_MOVE_EXT_FL_AUTO_DEFRAG;
+ context->auto_defrag = 1;
+ } else {
+ if (copy_from_user(&range, (struct ocfs2_move_extents *)argp,
+ sizeof(range))) {
+ status = -EFAULT;
+ goto out;
+ }
+ }
+
+ if (range.me_start > i_size_read(inode))
+ goto out;
+
+ if (range.me_start + range.me_len > i_size_read(inode))
+ range.me_len = i_size_read(inode) - range.me_start;
+
+ context->range = ⦥
+
+ if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
+ context->auto_defrag = 1;
+ if (!range.me_thresh)
+ /*
+ * ok, the default theshold for the defragmentation
+ * is 1M, since our maximum clustersize was 1M also.
+ * any thought?
+ */
+ range.me_thresh = 1024 * 1024;
+ } else {
+ /*
+ * first best-effort attempt to validate and adjust the goal
+ * (physical address in block), while it can't guarantee later
+ * operation can succeed all the time since global_bitmap may
+ * change a bit over time.
+ */
+
+ status = ocfs2_validate_and_adjust_move_goal(inode, &range);
+ if (status)
+ goto out;
+ }
+
+ status = ocfs2_move_extents(context);
+ if (status)
+ mlog_errno(status);
+out:
+ /*
+ * movement/defragmentation may end up being partially completed,
+ * that's the reason why we need to return userspace the finished
+ * length and new_offset even if failure happens somewhere.
+ */
+ if (argp) {
+ if (copy_to_user((struct ocfs2_move_extents *)argp, &range,
+ sizeof(range)))
+ status = -EFAULT;
+ }
+
+ kfree(context);
+
+ mnt_drop_write(filp->f_path.mnt);
+
+ return status;
+}
diff --git a/fs/ocfs2/move_extents.h b/fs/ocfs2/move_extents.h
index eba4044..d9f0f29 100644
--- a/fs/ocfs2/move_extents.h
+++ b/fs/ocfs2/move_extents.h
@@ -17,4 +17,6 @@
#ifndef OCFS2_MOVE_EXTENTS_H
#define OCFS2_MOVE_EXTENTS_H
+int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp);
+
#endif /* OCFS2_MOVE_EXTENTS_H */
--
1.5.5
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