diff options
| author | Mikulas Patocka | 2020-02-24 10:20:31 +0100 |
|---|---|---|
| committer | Mike Snitzer | 2020-03-24 11:26:18 -0400 |
| commit | d53f1fafec9d086f1c5166436abefdaef30e0363 (patch) | |
| tree | d876e8292420f04d2c38ebf5defa92683fdcf982 /drivers/md | |
| parent | eaab4bde6e645a37febba9a4126dc71e5994e3a1 (diff) | |
dm writecache: do direct write if the cache is full
If the cache device is full, we do a direct write to the origin device.
Note that we must not do it if the written block is already in the cache.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-writecache.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index a09bdc000e64..dc1e10c6ecd7 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -1194,6 +1194,7 @@ read_next_block: } } else { do { + bool found_entry = false; if (writecache_has_error(wc)) goto unlock_error; e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0); @@ -1204,9 +1205,21 @@ read_next_block: wc->overwrote_committed = true; goto bio_copy; } + found_entry = true; } e = writecache_pop_from_freelist(wc, (sector_t)-1); if (unlikely(!e)) { + if (!found_entry) { + e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING); + if (e) { + sector_t next_boundary = read_original_sector(wc, e) - bio->bi_iter.bi_sector; + BUG_ON(!next_boundary); + if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) { + dm_accept_partial_bio(bio, next_boundary); + } + } + goto unlock_remap_origin; + } writecache_wait_on_freelist(wc); continue; } |