Merge tag 'for-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...

[linux-block.git] / fs / btrfs / extent_io.c

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index eed81a7e36a4d0dd1cd1fbd05b4b6383f0fc32f8..cf4f19e80e2f7f174ecdd245f4dd4b5e9d7dbd87 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3233,7 +3233,7 @@ static int btrfs_bio_add_page(struct btrfs_bio_ctrl *bio_ctrl,
        u32 bio_size = bio->bi_iter.bi_size;
        u32 real_size;
        const sector_t sector = disk_bytenr >> SECTOR_SHIFT;
-       bool contig;
+       bool contig = false;
        int ret;
 
        ASSERT(bio);
@@ -3242,10 +3242,35 @@ static int btrfs_bio_add_page(struct btrfs_bio_ctrl *bio_ctrl,
        if (bio_ctrl->compress_type != compress_type)
                return 0;
 
-       if (bio_ctrl->compress_type != BTRFS_COMPRESS_NONE)
+
+       if (bio->bi_iter.bi_size == 0) {
+               /* We can always add a page into an empty bio. */
+               contig = true;
+       } else if (bio_ctrl->compress_type == BTRFS_COMPRESS_NONE) {
+               struct bio_vec *bvec = bio_last_bvec_all(bio);
+
+               /*
+                * The contig check requires the following conditions to be met:
+                * 1) The pages are belonging to the same inode
+                *    This is implied by the call chain.
+                *
+                * 2) The range has adjacent logical bytenr
+                *
+                * 3) The range has adjacent file offset
+                *    This is required for the usage of btrfs_bio->file_offset.
+                */
+               if (bio_end_sector(bio) == sector &&
+                   page_offset(bvec->bv_page) + bvec->bv_offset +
+                   bvec->bv_len == page_offset(page) + pg_offset)
+                       contig = true;
+       } else {
+               /*
+                * For compression, all IO should have its logical bytenr
+                * set to the starting bytenr of the compressed extent.
+                */
                contig = bio->bi_iter.bi_sector == sector;
-       else
-               contig = bio_end_sector(bio) == sector;
+       }
+
        if (!contig)
                return 0;