diff options
| author | Christoph Hellwig <hch@lst.de> | 2016-07-19 12:23:33 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2016-07-21 02:35:20 +0300 |
| commit | e950fdf71c9b4a6b63b58fed78956a96cc907402 (patch) | |
| tree | eadcf71a0abf034caaab5b019fe8f290df7fbc14 | |
| parent | b09dcf585df959cf26270e65941ea1f79a1345aa (diff) | |
| download | linux-e950fdf71c9b4a6b63b58fed78956a96cc907402.tar.xz | |
block: introduce BLKDEV_DISCARD_ZERO to fix zeroout
Currently blkdev_issue_zeroout cascades down from discards (if the driver
guarantees that discards zero data), to WRITE SAME and then to a loop
writing zeroes. Unfortunately we ignore run-time EOPNOTSUPP errors in the
block layer blkdev_issue_discard helper to work around DM volumes that
may have mixed discard support underneath.
This patch intoroduces a new BLKDEV_DISCARD_ZERO flag to
blkdev_issue_discard that indicates we are called for zeroing operation.
This allows both to ignore the EOPNOTSUPP hack and actually consolidating
the discard_zeroes_data check into the function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | block/blk-lib.c | 17 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 4 |
2 files changed, 14 insertions, 7 deletions
diff --git a/block/blk-lib.c b/block/blk-lib.c index 78626c2fde33..45b35b15496f 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -36,12 +36,17 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, return -ENXIO; if (flags & BLKDEV_DISCARD_SECURE) { + if (flags & BLKDEV_DISCARD_ZERO) + return -EOPNOTSUPP; if (!blk_queue_secure_erase(q)) return -EOPNOTSUPP; op = REQ_OP_SECURE_ERASE; } else { if (!blk_queue_discard(q)) return -EOPNOTSUPP; + if ((flags & BLKDEV_DISCARD_ZERO) && + !q->limits.discard_zeroes_data) + return -EOPNOTSUPP; op = REQ_OP_DISCARD; } @@ -116,7 +121,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, &bio); if (!ret && bio) { ret = submit_bio_wait(bio); - if (ret == -EOPNOTSUPP) + if (ret == -EOPNOTSUPP && !(flags & BLKDEV_DISCARD_ZERO)) ret = 0; } blk_finish_plug(&plug); @@ -241,11 +246,11 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, bool discard) { - struct request_queue *q = bdev_get_queue(bdev); - - if (discard && blk_queue_discard(q) && q->limits.discard_zeroes_data && - blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, 0) == 0) - return 0; + if (discard) { + if (!blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, + BLKDEV_DISCARD_ZERO)) + return 0; + } if (bdev_write_same(bdev) && blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 53fee6123893..156455cb07ad 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1137,7 +1137,9 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, return bqt->tag_index[tag]; } -#define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ + +#define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */ +#define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */ extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, |