kernel/linux.git/block/blk-map.c, branch v6.12.80

block: fix queue limits checks in blk_rq_map_user_bvec for real

2024-10-28T18:35:05+00:00

blk_rq_map_user_bvec currently only has ad-hoc checks for queue limits, and the last fix to it enabled valid NVMe I/O to pass, but also allowed invalid one for drivers that set a max_segment_size or seg_boundary limit. Fix it once for all by using the bio_split_rw_at helper from the I/O path that indicates if and where a bio would be have to be split to adhere to the queue limits, and it returns a positive value, turn that into -EREMOTEIO to retry using the copy path. Fixes: 2ff949441802 ("block: fix sanity checks in blk_rq_map_user_bvec") Signed-off-by: Christoph Hellwig Reviewed-by: John Garry Link: https://lore.kernel.org/r/20241028090840.446180-1-hch@lst.de Signed-off-by: Jens Axboe

block: fix sanity checks in blk_rq_map_user_bvec

2024-10-23T23:02:48+00:00

blk_rq_map_user_bvec contains a check bytes + bv->bv_len > nr_iter which causes unnecessary failures in NVMe passthrough I/O, reproducible as follows: - register a 2 page, page-aligned buffer against a ring - use that buffer to do a 1 page io_uring NVMe passthrough read The second (i = 1) iteration of the loop in blk_rq_map_user_bvec will then have nr_iter == 1 page, bytes == 1 page, bv->bv_len == 1 page, so the check bytes + bv->bv_len > nr_iter will succeed, causing the I/O to fail. This failure is unnecessary, as when the check succeeds, it means we've checked the entire buffer that will be used by the request - i.e. blk_rq_map_user_bvec should complete successfully. Therefore, terminate the loop early and return successfully when the check bytes + bv->bv_len > nr_iter succeeds. While we're at it, also remove the check that all segments in the bvec are single-page. While this seems to be true for all users of the function, it doesn't appear to be required anywhere downstream. CC: stable@vger.kernel.org Signed-off-by: Xinyu Zhang Co-developed-by: Uday Shankar Signed-off-by: Uday Shankar Fixes: 37987547932c ("block: extend functionality to map bvec iterator") Link: https://lore.kernel.org/r/20241023211519.4177873-1-ushankar@purestorage.com Signed-off-by: Jens Axboe

block: don't free the integrity payload in bio_integrity_unmap_free_user

2024-07-03T16:21:16+00:00

Now that the integrity payload is always freed in bio_uninit, don't bother freeing it a little earlier in bio_integrity_unmap_free_user. With that the separate bio_integrity_unmap_free_user can go away by just passing the bio to bio_integrity_unmap_user. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Kanchan Joshi Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20240702151047.1746127-7-hch@lst.de Signed-off-by: Jens Axboe

block: call bio_integrity_unmap_free_user from blk_rq_unmap_user

2024-07-03T16:21:16+00:00

blk_rq_unmap_user always unmaps user space pass-through request. If such a request has integrity data attached it must come from a user mapping as well. Call bio_integrity_unmap_free_user from blk_rq_unmap_user and remove the nvme_unmap_bio wrapper in the nvme driver. Signed-off-by: Christoph Hellwig Reviewed-by: Kanchan Joshi Reviewed-by: Anuj Gupta Reviewed-by: Johannes Thumshirn Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20240702151047.1746127-5-hch@lst.de Signed-off-by: Jens Axboe

block: move dma_pad_mask into queue_limits

2024-06-26T15:37:35+00:00

dma_pad_mask is a queue_limits by all ways of looking at it, so move it there and set it through the atomic queue limits APIs. Add a little helper that takes the alignment and pad into account to simplify the code that is touched a bit. Note that there never was any need for the > check in blk_queue_update_dma_pad, this probably was just copy and paste from dma_update_dma_alignment. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20240626142637.300624-9-hch@lst.de Signed-off-by: Jens Axboe

block: Fix WARNING in _copy_from_iter

2024-01-23T15:56:55+00:00

Syzkaller reports a warning in _copy_from_iter because an iov_iter is supposedly used in the wrong direction. The reason is that syzcaller managed to generate a request with a transfer direction of SG_DXFER_TO_FROM_DEV. This instructs the kernel to copy user buffers into the kernel, read into the copied buffers and then copy the data back to user space. Thus the iovec is used in both directions. Detect this situation in the block layer and construct a new iterator with the correct direction for the copy-in. Reported-by: syzbot+a532b03fdfee2c137666@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/0000000000009b92c10604d7a5e9@google.com/t/ Reported-by: syzbot+63dec323ac56c28e644f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/0000000000003faaa105f6e7c658@google.com/T/ Signed-off-by: Christian A. Ehrhardt Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20240121202634.275068-1-lk@c--e.de Signed-off-by: Jens Axboe

block: fix pin count management when merging same-page segments

2023-09-06T13:32:27+00:00

There is no need to unpin the added page when adding it to the bio fails as that is done by the loop below. Instead we want to unpin it when adding a single page to the bio more than once as bio_release_pages will only unpin it once. Fixes: d1916c86ccdc ("block: move same page handling from __bio_add_pc_page to the callers") Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20230905124731.328255-1-hch@lst.de Signed-off-by: Jens Axboe

Merge tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux

2023-06-26T19:47:20+00:00

Pull block updates from Jens Axboe: - NVMe pull request via Keith: - Various cleanups all around (Irvin, Chaitanya, Christophe) - Better struct packing (Christophe JAILLET) - Reduce controller error logs for optional commands (Keith) - Support for >=64KiB block sizes (Daniel Gomez) - Fabrics fixes and code organization (Max, Chaitanya, Daniel Wagner) - bcache updates via Coly: - Fix a race at init time (Mingzhe Zou) - Misc fixes and cleanups (Andrea, Thomas, Zheng, Ye) - use page pinning in the block layer for dio (David) - convert old block dio code to page pinning (David, Christoph) - cleanups for pktcdvd (Andy) - cleanups for rnbd (Guoqing) - use the unchecked __bio_add_page() for the initial single page additions (Johannes) - fix overflows in the Amiga partition handling code (Michael) - improve mq-deadline zoned device support (Bart) - keep passthrough requests out of the IO schedulers (Christoph, Ming) - improve support for flush requests, making them less special to deal with (Christoph) - add bdev holder ops and shutdown methods (Christoph) - fix the name_to_dev_t() situation and use cases (Christoph) - decouple the block open flags from fmode_t (Christoph) - ublk updates and cleanups, including adding user copy support (Ming) - BFQ sanity checking (Bart) - convert brd from radix to xarray (Pankaj) - constify various structures (Thomas, Ivan) - more fine grained persistent reservation ioctl capability checks (Jingbo) - misc fixes and cleanups (Arnd, Azeem, Demi, Ed, Hengqi, Hou, Jan, Jordy, Li, Min, Yu, Zhong, Waiman) * tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux: (266 commits) scsi/sg: don't grab scsi host module reference ext4: Fix warning in blkdev_put() block: don't return -EINVAL for not found names in devt_from_devname cdrom: Fix spectre-v1 gadget block: Improve kernel-doc headers blk-mq: don't insert passthrough request into sw queue bsg: make bsg_class a static const structure ublk: make ublk_chr_class a static const structure aoe: make aoe_class a static const structure block/rnbd: make all 'class' structures const block: fix the exclusive open mask in disk_scan_partitions block: add overflow checks for Amiga partition support block: change all __u32 annotations to __be32 in affs_hardblocks.h block: fix signed int overflow in Amiga partition support block: add capacity validation in bdev_add_partition() block: fine-granular CAP_SYS_ADMIN for Persistent Reservation block: disallow Persistent Reservation on partitions reiserfs: fix blkdev_put() warning from release_journal_dev() block: fix wrong mode for blkdev_get_by_dev() from disk_scan_partitions() block: document the holder argument to blkdev_get_by_path ...

block: convert bio_map_user_iov to use iov_iter_extract_pages

2023-05-24T14:42:44+00:00

This will pin pages or leave them unaltered rather than getting a ref on them as appropriate to the iterator. The pages need to be pinned for DIO rather than having refs taken on them to prevent VM copy-on-write from malfunctioning during a concurrent fork() (the result of the I/O could otherwise end up being visible to/affected by the child process). Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: John Hubbard cc: Al Viro cc: Jens Axboe cc: Jan Kara cc: Matthew Wilcox cc: Logan Gunthorpe cc: linux-block@vger.kernel.org Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20230522205744.2825689-7-dhowells@redhat.com Signed-off-by: Jens Axboe

block: Replace BIO_NO_PAGE_REF with BIO_PAGE_REFFED with inverted logic

2023-05-24T14:42:44+00:00

Replace BIO_NO_PAGE_REF with a BIO_PAGE_REFFED flag that has the inverted meaning is only set when a page reference has been acquired that needs to be released by bio_release_pages(). Signed-off-by: Christoph Hellwig Signed-off-by: David Howells Reviewed-by: John Hubbard cc: Al Viro cc: Jens Axboe cc: Jan Kara cc: Matthew Wilcox cc: Logan Gunthorpe cc: linux-block@vger.kernel.org Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20230522205744.2825689-4-dhowells@redhat.com Signed-off-by: Jens Axboe