@@ -1008,7 +1008,7 @@ static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
u64 *last_len, u64 *skip, u64 *defrag_end,
- int compress)
+ int compress, int compress_type)
{
struct extent_map *em;
int ret = 1;
@@ -1043,8 +1043,29 @@ static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
* real extent, don't bother defragging it
*/
if (!compress && (*last_len == 0 || *last_len >= thresh) &&
- (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
+ (em->len >= thresh || (!next_mergeable && !prev_mergeable))) {
ret = 0;
+ goto out;
+ }
+
+
+ /*
+ * Try not recompress compressed extents
+ * thresh >= BTRFS_MAX_UNCOMPRESSED will lead to
+ * recompress all compressed extents
+ */
+ if (em->compress_type != 0 && thresh >= BTRFS_MAX_UNCOMPRESSED) {
+ if (!compress) {
+ if (em->len == BTRFS_MAX_UNCOMPRESSED)
+ ret = 0;
+ } else {
+ if (em->compress_type != compress_type)
+ goto out;
+ if (em->len == BTRFS_MAX_UNCOMPRESSED)
+ ret = 0;
+ }
+ }
+
out:
/*
* last_len ends up being a counter of how many bytes we've defragged.
@@ -1342,7 +1363,8 @@ int btrfs_defrag_file(struct inode *inode, struct file *file,
if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
extent_thresh, &last_len, &skip,
- &defrag_end, do_compress)){
+ &defrag_end, do_compress,
+ compress_type)){
unsigned long next;
/*
* the should_defrag function tells us how much to skip
Both, defrag ioctl and autodefrag - call btrfs_defrag_file() for file defragmentation. Kernel default target extent size - 256KiB. Btrfs progs default - 32MiB. Both bigger then maximum size of compressed extent - 128KiB. That lead to rewrite all compressed data on disk. Fix that by check compression extents with different logic. As addition, make should_defrag_range() understood compressed extent type, if requested target compression are same as current extent compression type. Just don't recompress/rewrite extents. To avoid useless recompression of compressed extents. Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com> --- fs/btrfs/ioctl.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-)