user/sven/linux.git/fs/block_dev.c, branch v5.3.11

block: remove REQ_NOWAIT_INLINE

2019-08-15T17:09:16Z

We had a few issues with this code, and there's still a problem around how we deal with error handling for chained/split bios. For now, just revert the code and we'll try again with a thoroug solution. This reverts commits: e15c2ffa1091 ("block: fix O_DIRECT error handling for bio fragments") 0eb6ddfb865c ("block: Fix __blkdev_direct_IO() for bio fragments") 6a43074e2f46 ("block: properly handle IOCB_NOWAIT for async O_DIRECT IO") 893a1c97205a ("blk-mq: allow REQ_NOWAIT to return an error inline") Signed-off-by: Jens Axboe

bdev: Fixup error handling in blkdev_get()

2019-08-08T13:37:03Z

Commit 89e524c04fa9 ("loop: Fix mount(2) failure due to race with LOOP_SET_FD") converted blkdev_get() to use the new helpers for finishing claiming of a block device. However the conversion botched the error handling in blkdev_get() and thus the bdev has been marked as held even in case __blkdev_get() returned error. This led to occasional warnings with block/001 test from blktests like: kernel: WARNING: CPU: 5 PID: 907 at fs/block_dev.c:1899 __blkdev_put+0x396/0x3a0 Correct the error handling. CC: stable@vger.kernel.org Fixes: 89e524c04fa9 ("loop: Fix mount(2) failure due to race with LOOP_SET_FD") Signed-off-by: Jan Kara Signed-off-by: Jens Axboe

block: fix O_DIRECT error handling for bio fragments

2019-08-07T18:19:43Z

0eb6ddfb865c tried to fix this up, but introduced a use-after-free of dio. Additionally, we still had an issue with error handling, as reported by Darrick: "I noticed a regression in xfs/747 (an unreleased xfstest for the xfs_scrub media scanning feature) on 5.3-rc3. I'll condense that down to a simpler reproducer: error-test: 0 209 linear 8:48 0 error-test: 209 1 error error-test: 210 6446894 linear 8:48 210 Basically we have a ~3G /dev/sdd and we set up device mapper to fail IO for sector 209 and to pass the io to the scsi device everywhere else. On 5.3-rc3, performing a directio pread of this range with a < 1M buffer (in other words, a request for fewer than MAX_BIO_PAGES bytes) yields EIO like you'd expect: pread64(3, 0x7f880e1c7000, 1048576, 0) = -1 EIO (Input/output error) pread: Input/output error +++ exited with 0 +++ But doing it with a larger buffer succeeds(!): pread64(3, "XFSB\0\0\20\0\0\0\0\0\0\fL\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 1146880, 0) = 1146880 read 1146880/1146880 bytes at offset 0 1 MiB, 1 ops; 0.0009 sec (1.124 GiB/sec and 1052.6316 ops/sec) +++ exited with 0 +++ (Note that the part of the buffer corresponding to the dm-error area is uninitialized) On 5.3-rc2, both commands would fail with EIO like you'd expect. The only change between rc2 and rc3 is commit 0eb6ddfb865c ("block: Fix __blkdev_direct_IO() for bio fragments"). AFAICT we end up in __blkdev_direct_IO with a 1120K buffer, which gets split into two bios: one for the first BIO_MAX_PAGES worth of data (1MB) and a second one for the 96k after that." Fix this by noting that it's always safe to dereference dio if we get BLK_QC_T_EAGAIN returned, as end_io hasn't been run for that case. So we can safely increment the dio size before calling submit_bio(), and then decrement it on failure (not that it really matters, as the bio and dio are going away). For error handling, return to the original method of just using 'ret' for tracking the error, and the size tracking in dio->size. Fixes: 0eb6ddfb865c ("block: Fix __blkdev_direct_IO() for bio fragments") Fixes: 6a43074e2f46 ("block: properly handle IOCB_NOWAIT for async O_DIRECT IO") Reported-by: Darrick J. Wong Signed-off-by: Jens Axboe

block: Fix __blkdev_direct_IO() for bio fragments

2019-08-01T19:51:18Z

The recent fix to properly handle IOCB_NOWAIT for async O_DIRECT IO (patch 6a43074e2f46) introduced two problems with BIO fragment handling for direct IOs: 1) The dio size processed is calculated by incrementing the ret variable by the size of the bio fragment issued for the dio. However, this size is obtained directly from bio->bi_iter.bi_size AFTER the bio submission which may result in referencing the bi_size value after the bio completed, resulting in an incorrect value use. 2) The ret variable is not incremented by the size of the last bio fragment issued for the bio, leading to an invalid IO size being returned to the user. Fix both problem by using dio->size (which is incremented before the bio submission) to update the value of ret after bio submissions, including for the last bio fragment issued. Fixes: 6a43074e2f46 ("block: properly handle IOCB_NOWAIT for async O_DIRECT IO") Reported-by: Masato Suzuki Signed-off-by: Damien Le Moal Signed-off-by: Jens Axboe

loop: Fix mount(2) failure due to race with LOOP_SET_FD

2019-07-30T19:16:57Z

Commit 33ec3e53e7b1 ("loop: Don't change loop device under exclusive opener") made LOOP_SET_FD ioctl acquire exclusive block device reference while it updates loop device binding. However this can make perfectly valid mount(2) fail with EBUSY due to racing LOOP_SET_FD holding temporarily the exclusive bdev reference in cases like this: for i in {a..z}{a..z}; do dd if=/dev/zero of=$i.image bs=1k count=0 seek=1024 mkfs.ext2 $i.image mkdir mnt$i done echo "Run" for i in {a..z}{a..z}; do mount -o loop -t ext2 $i.image mnt$i & done Fix the problem by not getting full exclusive bdev reference in LOOP_SET_FD but instead just mark the bdev as being claimed while we update the binding information. This just blocks new exclusive openers instead of failing them with EBUSY thus fixing the problem. Fixes: 33ec3e53e7b1 ("loop: Don't change loop device under exclusive opener") Cc: stable@vger.kernel.org Tested-by: Kai-Heng Feng Signed-off-by: Jan Kara Signed-off-by: Jens Axboe

Merge tag 'for-linus-20190726' of git://git.kernel.dk/linux-block

2019-07-26T17:32:12Z

Pull block fixes from Jens Axboe: - Several io_uring fixes/improvements: - Blocking fix for O_DIRECT (me) - Latter page slowness for registered buffers (me) - Fix poll hang under certain conditions (me) - Defer sequence check fix for wrapped rings (Zhengyuan) - Mismatch in async inc/dec accounting (Zhengyuan) - Memory ordering issue that could cause stall (Zhengyuan) - Track sequential defer in bytes, not pages (Zhengyuan) - NVMe pull request from Christoph - Set of hang fixes for wbt (Josef) - Redundant error message kill for libahci (Ding) - Remove unused blk_mq_sched_started_request() and related ops (Marcos) - drbd dynamic alloc shash descriptor to reduce stack use (Arnd) - blkcg ->pd_stat() non-debug print (Tejun) - bcache memory leak fix (Wei) - Comment fix (Akinobu) - BFQ perf regression fix (Paolo) * tag 'for-linus-20190726' of git://git.kernel.dk/linux-block: (24 commits) io_uring: ensure ->list is initialized for poll commands Revert "nvme-pci: don't create a read hctx mapping without read queues" nvme: fix multipath crash when ANA is deactivated nvme: fix memory leak caused by incorrect subsystem free nvme: ignore subnqn for ADATA SX6000LNP drbd: dynamically allocate shash descriptor block: blk-mq: Remove blk_mq_sched_started_request and started_request bcache: fix possible memory leak in bch_cached_dev_run() io_uring: track io length in async_list based on bytes io_uring: don't use iov_iter_advance() for fixed buffers block: properly handle IOCB_NOWAIT for async O_DIRECT IO blk-mq: allow REQ_NOWAIT to return an error inline io_uring: add a memory barrier before atomic_read rq-qos: use a mb for got_token rq-qos: set ourself TASK_UNINTERRUPTIBLE after we schedule rq-qos: don't reset has_sleepers on spurious wakeups rq-qos: fix missed wake-ups in rq_qos_throttle wait: add wq_has_single_sleeper helper block, bfq: check also in-flight I/O in dispatch plugging block: fix sysfs module parameters directory path in comment ...

block: properly handle IOCB_NOWAIT for async O_DIRECT IO

2019-07-22T03:46:29Z

A caller is supposed to pass in REQ_NOWAIT if we can't block for any given operation, but O_DIRECT for block devices just ignore this. Hence we'll block for various resource shortages on the block layer side, like having to wait for requests. Use the new REQ_NOWAIT_INLINE to ask for this error to be returned inline, so we can handle it appropriately and return -EAGAIN to the caller. Signed-off-by: Jens Axboe

Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2019-07-19T17:42:02Z

Pull vfs mount updates from Al Viro: "The first part of mount updates. Convert filesystems to use the new mount API" * 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) mnt_init(): call shmem_init() unconditionally constify ksys_mount() string arguments don't bother with registering rootfs init_rootfs(): don't bother with init_ramfs_fs() vfs: Convert smackfs to use the new mount API vfs: Convert selinuxfs to use the new mount API vfs: Convert securityfs to use the new mount API vfs: Convert apparmorfs to use the new mount API vfs: Convert openpromfs to use the new mount API vfs: Convert xenfs to use the new mount API vfs: Convert gadgetfs to use the new mount API vfs: Convert oprofilefs to use the new mount API vfs: Convert ibmasmfs to use the new mount API vfs: Convert qib_fs/ipathfs to use the new mount API vfs: Convert efivarfs to use the new mount API vfs: Convert configfs to use the new mount API vfs: Convert binfmt_misc to use the new mount API convenience helper: get_tree_single() convenience helper get_tree_nodev() vfs: Kill sget_userns() ...

block_dev: use bio_release_pages in bio_unmap_user

2019-06-29T15:47:31Z

Use bio_release_pages instead of duplicating it. Reviewed-by: Chaitanya Kulkarni Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block_dev: use bio_release_pages in blkdev_bio_end_io

2019-06-29T15:47:31Z

Use bio_release_pages instead of duplicating it. Reviewed-by: Minwoo Im Reviewed-by: Chaitanya Kulkarni Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe