From 30f1e724142242a453f92d90b33e030014900bf0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 6 May 2024 06:20:23 +0200 Subject: [PATCH] block: move discard checks into the ioctl handler Most bio operations get basic sanity checking in submit_bio and anything more complicated than that is done in the callers. Discards are a bit different from that in that a lot of checking is done in __blkdev_issue_discard, and the specific errnos for that are returned to userspace. Move the checks that require specific errnos to the ioctl handler instead, and just leave the basic sanity checking in submit_bio for the other handlers. This introduces two changes in behavior: 1) the logical block size alignment check of the start and len is lost for non-ioctl callers. This matches what is done for other operations including reads and writes. We should probably verify this for all bios, but for now make discards match the normal flow. 2) for non-ioctl callers all errors are reported on I/O completion now instead of synchronously. Callers in general mostly ignore or log errors so this will actually simplify the code once cleaned up Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20240506042027.2289826-3-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-lib.c | 13 ------------- block/ioctl.c | 7 +++++-- 2 files changed, 5 insertions(+), 15 deletions(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index 7ec3e170e7f6..6e54ef140bab 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -39,19 +39,6 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, struct bio **biop) { struct bio *bio = *biop; - sector_t bs_mask; - - if (bdev_read_only(bdev)) - return -EPERM; - if (!bdev_max_discard_sectors(bdev)) - return -EOPNOTSUPP; - - bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1; - if ((sector | nr_sects) & bs_mask) - return -EINVAL; - - if (!nr_sects) - return -EINVAL; while (nr_sects) { sector_t req_sects = diff --git a/block/ioctl.c b/block/ioctl.c index 06ff3023e2a1..49fa02b17ec1 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -95,6 +95,7 @@ static int compat_blkpg_ioctl(struct block_device *bdev, static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode, unsigned long arg) { + unsigned int bs_mask = bdev_logical_block_size(bdev) - 1; uint64_t range[2]; uint64_t start, len; struct inode *inode = bdev->bd_inode; @@ -105,6 +106,8 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode, if (!bdev_max_discard_sectors(bdev)) return -EOPNOTSUPP; + if (bdev_read_only(bdev)) + return -EPERM; if (copy_from_user(range, (void __user *)arg, sizeof(range))) return -EFAULT; @@ -112,9 +115,9 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode, start = range[0]; len = range[1]; - if (start & 511) + if (!len) return -EINVAL; - if (len & 511) + if ((start | len) & bs_mask) return -EINVAL; if (start + len > bdev_nr_bytes(bdev))