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Diffstat (limited to 'drivers/md/bcache/request.c')
-rw-r--r--drivers/md/bcache/request.c17
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 73478a91a342..820d8402a1dc 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -379,13 +379,20 @@ static bool check_should_bypass(struct cached_dev *dc, struct bio *bio)
goto skip;
/*
- * Flag for bypass if the IO is for read-ahead or background,
- * unless the read-ahead request is for metadata
+ * If the bio is for read-ahead or background IO, bypass it or
+ * not depends on the following situations,
+ * - If the IO is for meta data, always cache it and no bypass
+ * - If the IO is not meta data, check dc->cache_reada_policy,
+ * BCH_CACHE_READA_ALL: cache it and not bypass
+ * BCH_CACHE_READA_META_ONLY: not cache it and bypass
+ * That is, read-ahead request for metadata always get cached
* (eg, for gfs2 or xfs).
*/
- if (bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND) &&
- !(bio->bi_opf & (REQ_META|REQ_PRIO)))
- goto skip;
+ if ((bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND))) {
+ if (!(bio->bi_opf & (REQ_META|REQ_PRIO)) &&
+ (dc->cache_readahead_policy != BCH_CACHE_READA_ALL))
+ goto skip;
+ }
if (bio->bi_iter.bi_sector & (c->sb.block_size - 1) ||
bio_sectors(bio) & (c->sb.block_size - 1)) {