Btrfs: add new defrag-range ioctl.
The btrfs defrag ioctl was limited to doing the entire file. This
commit adds a new interface that can defrag a specific range inside
the file.
It can also force compression on the file, allowing you to selectively
compress individual files after they were created, even when mount -o
compress isn't turned on.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 7d10d1c..3657925 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -379,7 +379,8 @@
* change at any time if we discover bad compression ratios.
*/
if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
- btrfs_test_opt(root, COMPRESS)) {
+ (btrfs_test_opt(root, COMPRESS) ||
+ (BTRFS_I(inode)->force_compress))) {
WARN_ON(pages);
pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
@@ -483,8 +484,10 @@
nr_pages_ret = 0;
/* flag the file so we don't compress in the future */
- if (!btrfs_test_opt(root, FORCE_COMPRESS))
+ if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
+ !(BTRFS_I(inode)->force_compress)) {
BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
+ }
}
if (will_compress) {
*num_added += 1;
@@ -1211,7 +1214,8 @@
else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
ret = run_delalloc_nocow(inode, locked_page, start, end,
page_started, 0, nr_written);
- else if (!btrfs_test_opt(root, COMPRESS))
+ else if (!btrfs_test_opt(root, COMPRESS) &&
+ !(BTRFS_I(inode)->force_compress))
ret = cow_file_range(inode, locked_page, start, end,
page_started, nr_written, 1);
else
@@ -3639,6 +3643,7 @@
bi->index_cnt = (u64)-1;
bi->last_unlink_trans = 0;
bi->ordered_data_close = 0;
+ bi->force_compress = 0;
extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
extent_io_tree_init(&BTRFS_I(inode)->io_tree,
inode->i_mapping, GFP_NOFS);