linux/block/bdev.c, branch v6.15

Merge tag 'block-6.15-20250424' of git://git.kernel.dk/linux

2025-04-25T18:34:39Z

Pull block fixes from Jens Axboe: - Fix autoloading of drivers from stat*(2) - Fix losing read-ahead setting one suspend/resume, when a device is re-probed. - Fix race between setting the block size and page cache updates. Includes a helper that a coming XFS fix will use as well. - ublk cancelation fixes. - ublk selftest additions and fixes. - NVMe pull via Christoph: - fix an out-of-bounds access in nvmet_enable_port (Richard Weinberger) * tag 'block-6.15-20250424' of git://git.kernel.dk/linux: ublk: fix race between io_uring_cmd_complete_in_task and ublk_cancel_cmd ublk: call ublk_dispatch_req() for handling UBLK_U_IO_NEED_GET_DATA block: don't autoload drivers on blk-cgroup configuration block: don't autoload drivers on stat block: remove the backing_inode variable in bdev_statx block: move blkdev_{get,put} _no_open prototypes out of blkdev.h block: never reduce ra_pages in blk_apply_bdi_limits selftests: ublk: common: fix _get_disk_dev_t for pre-9.0 coreutils selftests: ublk: remove useless 'delay_us' from 'struct dev_ctx' selftests: ublk: fix recover test block: hoist block size validation code to a separate function block: fix race between set_blocksize and read paths nvmet: fix out-of-bounds access in nvmet_enable_port

block: don't autoload drivers on stat

2025-04-24T13:35:23Z

blkdev_get_no_open can trigger the legacy autoload of block drivers. A simple stat of a block device has not historically done that, so disable this behavior again. Fixes: 9abcfbd235f5 ("block: Add atomic write support for statx") Signed-off-by: Christoph Hellwig Reviewed-by: Christian Brauner Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20250423053810.1683309-4-hch@lst.de Signed-off-by: Jens Axboe

block: remove the backing_inode variable in bdev_statx

2025-04-24T13:35:09Z

backing_inode is only used once, so remove it and update the comment describing the bdev lookup to be a bit more clear. Signed-off-by: Christoph Hellwig Reviewed-by: Christian Brauner Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20250423053810.1683309-3-hch@lst.de Signed-off-by: Jens Axboe

block: hoist block size validation code to a separate function

2025-04-23T19:58:06Z

Hoist the block size validation code to bdev_validate_blocksize so that we can call it from filesystems that don't care about the bdev pagecache manipulations of set_blocksize. Signed-off-by: Darrick J. Wong Reviewed-by: Luis Chamberlain Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/174543795720.4139148.840349813093799165.stgit@frogsfrogsfrogs Signed-off-by: Jens Axboe

block: fix race between set_blocksize and read paths

2025-04-23T19:58:06Z

With the new large sector size support, it's now the case that set_blocksize can change i_blksize and the folio order in a manner that conflicts with a concurrent reader and causes a kernel crash. Specifically, let's say that udev-worker calls libblkid to detect the labels on a block device. The read call can create an order-0 folio to read the first 4096 bytes from the disk. But then udev is preempted. Next, someone tries to mount an 8k-sectorsize filesystem from the same block device. The filesystem calls set_blksize, which sets i_blksize to 8192 and the minimum folio order to 1. Now udev resumes, still holding the order-0 folio it allocated. It then tries to schedule a read bio and do_mpage_readahead tries to create bufferheads for the folio. Unfortunately, blocks_per_folio == 0 because the page size is 4096 but the blocksize is 8192 so no bufferheads are attached and the bh walk never sets bdev. We then submit the bio with a NULL block device and crash. Therefore, truncate the page cache after flushing but before updating i_blksize. However, that's not enough -- we also need to lock out file IO and page faults during the update. Take both the i_rwsem and the invalidate_lock in exclusive mode for invalidations, and in shared mode for read/write operations. I don't know if this is the correct fix, but xfs/259 found it. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Luis Chamberlain Tested-by: Shin'ichiro Kawasaki Link: https://lore.kernel.org/r/174543795699.4139148.2086129139322431423.stgit@frogsfrogsfrogs Signed-off-by: Jens Axboe

fs: move the bdex_statx call to vfs_getattr_nosec

2025-04-17T08:14:34Z

Currently bdex_statx is only called from the very high-level vfs_statx_path function, and thus bypassing it for in-kernel calls to vfs_getattr or vfs_getattr_nosec. This breaks querying the block ѕize of the underlying device in the loop driver and also is a pitfall for any other new kernel caller. Move the call into the lowest level helper to ensure all callers get the right results. Fixes: 2d985f8c6b91 ("vfs: support STATX_DIOALIGN on block devices") Fixes: f4774e92aab8 ("loop: take the file system minimum dio alignment into account") Reported-by: "Darrick J. Wong" Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/20250417064042.712140-1-hch@lst.de Signed-off-by: Christian Brauner

bdev: add back PAGE_SIZE block size validation for sb_set_blocksize()

2025-03-07T11:56:05Z

The commit titled "block/bdev: lift block size restrictions to 64k" lifted the block layer's max supported block size to 64k inside the helper blk_validate_block_size() now that we support large folios. However in lifting the block size we also removed the silly use cases many filesystems have to use sb_set_blocksize() to *verify* that the block size <= PAGE_SIZE. The call to sb_set_blocksize() was used to check the block size <= PAGE_SIZE since historically we've always supported userspace to create for example 64k block size filesystems even on 4k page size systems, but what we didn't allow was mounting them. Older filesystems have been using the check with sb_set_blocksize() for years. While, we could argue that such checks should be filesystem specific, there are much more users of sb_set_blocksize() than LBS enabled filesystem on upstream, so just do the easier thing and bring back the PAGE_SIZE check for sb_set_blocksize() users and only skip it for LBS enabled filesystems. This will ensure that tests such as generic/466 when run in a loop against say, ext4, won't try to try to actually mount a filesystem with a block size larger than your filesystem supports given your PAGE_SIZE and in the worst case crash. Cc: Kent Overstreet Signed-off-by: Luis Chamberlain Link: https://lore.kernel.org/r/20250307020403.3068567-1-mcgrof@kernel.org Reviewed-by: Kent Overstreet Reviewed-by: "Darrick J. Wong" Signed-off-by: Christian Brauner

bdev: use bdev_io_min() for statx block size

2025-02-24T10:44:44Z

You can use lsblk to query for a block device block device block size: lsblk -o MIN-IO /dev/nvme0n1 MIN-IO 4096 The min-io is the minimum IO the block device prefers for optimal performance. In turn we map this to the block device block size. The current block size exposed even for block devices with an LBA format of 16k is 4k. Likewise devices which support 4k LBA format but have a larger Indirection Unit of 16k have an exposed block size of 4k. This incurs read-modify-writes on direct IO against devices with a min-io larger than the page size. To fix this, use the block device min io, which is the minimal optimal IO the device prefers. With this we now get: lsblk -o MIN-IO /dev/nvme0n1 MIN-IO 16384 And so userspace gets the appropriate information it needs for optimal performance. This is verified with blkalgn against mkfs against a device with LBA format of 4k but an NPWG of 16k (min io size) mkfs.xfs -f -b size=16k /dev/nvme3n1 blkalgn -d nvme3n1 --ops Write Block size : count distribution 0 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 0 | | 4096 -> 8191 : 0 | | 8192 -> 16383 : 0 | | 16384 -> 32767 : 66 |****************************************| 32768 -> 65535 : 0 | | 65536 -> 131071 : 0 | | 131072 -> 262143 : 2 |* | Block size: 14 - 66 Block size: 17 - 2 Algn size : count distribution 0 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 0 | | 4096 -> 8191 : 0 | | 8192 -> 16383 : 0 | | 16384 -> 32767 : 66 |****************************************| 32768 -> 65535 : 0 | | 65536 -> 131071 : 0 | | 131072 -> 262143 : 2 |* | Algn size: 14 - 66 Algn size: 17 - 2 Reviewed-by: Hannes Reinecke Signed-off-by: Luis Chamberlain Link: https://lore.kernel.org/r/20250221223823.1680616-9-mcgrof@kernel.org Reviewed-by: John Garry Signed-off-by: Christian Brauner

block/bdev: lift block size restrictions to 64k

2025-02-24T10:44:44Z

We now can support blocksizes larger than PAGE_SIZE, so in theory we should be able to lift the restriction up to the max supported page cache order. However bound ourselves to what we can currently validate and test. Through blktests and fstest we can validate up to 64k today. Reviewed-by: Hannes Reinecke Reviewed-by: "Matthew Wilcox (Oracle)" Signed-off-by: Luis Chamberlain Link: https://lore.kernel.org/r/20250221223823.1680616-8-mcgrof@kernel.org Signed-off-by: Christian Brauner

block/bdev: enable large folio support for large logical block sizes

2025-02-24T10:44:44Z

Call mapping_set_folio_min_order() when modifying the logical block size to ensure folios are allocated with the correct size. Reviewed-by: Luis Chamberlain Reviewed-by: "Matthew Wilcox (Oracle)" Signed-off-by: Hannes Reinecke Link: https://lore.kernel.org/r/20250221223823.1680616-7-mcgrof@kernel.org Reviewed-by: John Garry Reviewed-by: Hannes Reinecke Signed-off-by: Christian Brauner