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2019-09-19Merge tag 'vfs-5.4-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-0/+3
Pull swap access updates from Darrick Wong: "Prohibit writing to active swap files and swap partitions. There's no non-malicious use case for allowing userspace to scribble on storage that the kernel thinks it owns" * tag 'vfs-5.4-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: vfs: don't allow writes to swap files mm: set S_SWAPFILE on blockdev swap devices
2019-08-20vfs: don't allow writes to swap filesDarrick J. Wong1-0/+3
Don't let userspace write to an active swap file because the kernel effectively has a long term lease on the storage and things could get seriously corrupted if we let this happen. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-15block: remove REQ_NOWAIT_INLINEJens Axboe1-44/+5
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 <axboe@kernel.dk>
2019-08-08bdev: Fixup error handling in blkdev_get()Jan Kara1-1/+4
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 <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-07block: fix O_DIRECT error handling for bio fragmentsJens Axboe1-16/+12
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 <darrick.wong@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-01block: Fix __blkdev_direct_IO() for bio fragmentsDamien Le Moal1-1/+2
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 <masato.suzuki@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-07-30loop: Fix mount(2) failure due to race with LOOP_SET_FDJan Kara1-25/+58
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 <kai.heng.feng@canonical.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-07-26Merge tag 'for-linus-20190726' of git://git.kernel.dk/linux-blockLinus Torvalds1-8/+50
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 ...
2019-07-22block: properly handle IOCB_NOWAIT for async O_DIRECT IOJens Axboe1-8/+50
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 <axboe@kernel.dk>
2019-07-19Merge branch 'work.mount0' of ↵Linus Torvalds1-8/+9
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 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() ...
2019-06-29block_dev: use bio_release_pages in bio_unmap_userChristoph Hellwig1-9/+2
Use bio_release_pages instead of duplicating it. Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-29block_dev: use bio_release_pages in blkdev_bio_end_ioChristoph Hellwig1-7/+1
Use bio_release_pages instead of duplicating it. Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-27block: Don't revalidate bdev of hidden gendiskJan Kara1-9/+16
When hidden gendisk is revalidated, there's no point in revalidating associated block device as there's none. We would thus just create new bdev inode, report "detected capacity change from 0 to XXX" message and evict the bdev inode again. Avoid this pointless dance and confusing message in the kernel log. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-26vfs: Convert bdev to use the new mount APIDavid Howells1-8/+9
Convert the bdev filesystem to the new internal mount API as the old one will be obsoleted and removed. This allows greater flexibility in communication of mount parameters between userspace, the VFS and the filesystem. See Documentation/filesystems/mount_api.txt for more information. Signed-off-by: David Howells <dhowells@redhat.com> cc: Jens Axboe <axboe@kernel.dk> cc: linux-fsdevel@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-26mount_pseudo(): drop 'name' argument, switch to d_make_root()Al Viro1-1/+1
Once upon a time we used to set ->d_name of e.g. pipefs root so that d_path() on pipes would work. These days it's completely pointless - dentries of pipes are not even connected to pipefs root. However, mount_pseudo() had set the root dentry name (passed as the second argument) and callers kept inventing names to pass to it. Including those that didn't *have* any non-root dentries to start with... All of that had been pointless for about 8 years now; it's time to get rid of that cargo-culting... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-21treewide: Add SPDX license identifier for missed filesThomas Gleixner1-0/+1
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-15fs/block_dev.c: Remove duplicate headerSabyasachi Gupta1-1/+0
linux/dax.h is included more than once. Link: http://lkml.kernel.org/r/5c867e95.1c69fb81.4f15a.e5e4@mx.google.com Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com> Acked-by: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-08Merge branch 'work.misc' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted stuff, with no common topic whatsoever..." * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: libfs: document simple_get_link() Documentation/filesystems/Locking: fix ->get_link() prototype Documentation/filesystems/vfs.txt: document how ->i_link works Documentation/filesystems/vfs.txt: remove bogus "Last updated" date fs: use timespec64 in relatime_need_update fs/block_dev.c: remove unused include
2019-05-08Merge tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-blockLinus Torvalds1-4/+2
Pull block updates from Jens Axboe: "Nothing major in this series, just fixes and improvements all over the map. This contains: - Series of fixes for sed-opal (David, Jonas) - Fixes and performance tweaks for BFQ (via Paolo) - Set of fixes for bcache (via Coly) - Set of fixes for md (via Song) - Enabling multi-page for passthrough requests (Ming) - Queue release fix series (Ming) - Device notification improvements (Martin) - Propagate underlying device rotational status in loop (Holger) - Removal of mtip32xx trim support, which has been disabled for years (Christoph) - Improvement and cleanup of nvme command handling (Christoph) - Add block SPDX tags (Christoph) - Cleanup/hardening of bio/bvec iteration (Christoph) - A few NVMe pull requests (Christoph) - Removal of CONFIG_LBDAF (Christoph) - Various little fixes here and there" * tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block: (164 commits) block: fix mismerge in bvec_advance block: don't drain in-progress dispatch in blk_cleanup_queue() blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release blk-mq: always free hctx after request queue is freed blk-mq: split blk_mq_alloc_and_init_hctx into two parts blk-mq: free hw queue's resource in hctx's release handler blk-mq: move cancel of requeue_work into blk_mq_release blk-mq: grab .q_usage_counter when queuing request from plug code path block: fix function name in comment nvmet: protect discovery change log event list iteration nvme: mark nvme_core_init and nvme_core_exit static nvme: move command size checks to the core nvme-fabrics: check more command sizes nvme-pci: check more command sizes nvme-pci: remove an unneeded variable initialization nvme-pci: unquiesce admin queue on shutdown nvme-pci: shutdown on timeout during deletion nvme-pci: fix psdt field for single segment sgls nvme-multipath: don't print ANA group state by default nvme-multipath: split bios with the ns_head bio_set before submitting ...
2019-05-07Merge branch 'work.icache' of ↵Linus Torvalds1-11/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs inode freeing updates from Al Viro: "Introduction of separate method for RCU-delayed part of ->destroy_inode() (if any). Pretty much as posted, except that destroy_inode() stashes ->free_inode into the victim (anon-unioned with ->i_fops) before scheduling i_callback() and the last two patches (sockfs conversion and folding struct socket_wq into struct socket) are excluded - that pair should go through netdev once davem reopens his tree" * 'work.icache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (58 commits) orangefs: make use of ->free_inode() shmem: make use of ->free_inode() hugetlb: make use of ->free_inode() overlayfs: make use of ->free_inode() jfs: switch to ->free_inode() fuse: switch to ->free_inode() ext4: make use of ->free_inode() ecryptfs: make use of ->free_inode() ceph: use ->free_inode() btrfs: use ->free_inode() afs: switch to use of ->free_inode() dax: make use of ->free_inode() ntfs: switch to ->free_inode() securityfs: switch to ->free_inode() apparmor: switch to ->free_inode() rpcpipe: switch to ->free_inode() bpf: switch to ->free_inode() mqueue: switch to ->free_inode() ufs: switch to ->free_inode() coda: switch to ->free_inode() ...
2019-05-02bdev: switch to ->free_inode()Al Viro1-11/+3
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-01block: fix handling for BIO_NO_PAGE_REFMing Lei1-1/+2
Commit 399254aaf489211 ("block: add BIO_NO_PAGE_REF flag") introduces BIO_NO_PAGE_REF, and once this flag is set for one bio, all pages in the bio won't be get/put during IO. However, if one bio is submitted via __blkdev_direct_IO_simple(), even though BIO_NO_PAGE_REF is set, pages still may be put. Fixes this issue by avoiding to put pages if BIO_NO_PAGE_REF is set. Fixes: 399254aaf489211 ("block: add BIO_NO_PAGE_REF flag") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30block: remove the i argument to bio_for_each_segment_allChristoph Hellwig1-4/+2
We only have two callers that need the integer loop iterator, and they can easily maintain it themselves. Suggested-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Coly Li <colyli@suse.de> Reviewed-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-12block: fix the return errno for direct IOJason Yan1-4/+4
If the last bio returned is not dio->bio, the status of the bio will not assigned to dio->bio if it is error. This will cause the whole IO status wrong. ksoftirqd/21-117 [021] ..s. 4017.966090: 8,0 C N 4883648 [0] <idle>-0 [018] ..s. 4017.970888: 8,0 C WS 4924800 + 1024 [0] <idle>-0 [018] ..s. 4017.970909: 8,0 D WS 4935424 + 1024 [<idle>] <idle>-0 [018] ..s. 4017.970924: 8,0 D WS 4936448 + 321 [<idle>] ksoftirqd/21-117 [021] ..s. 4017.995033: 8,0 C R 4883648 + 336 [65475] ksoftirqd/21-117 [021] d.s. 4018.001988: myprobe1: (blkdev_bio_end_io+0x0/0x168) bi_status=7 ksoftirqd/21-117 [021] d.s. 4018.001992: myprobe: (aio_complete_rw+0x0/0x148) x0=0xffff802f2595ad80 res=0x12a000 res2=0x0 We always have to assign bio->bi_status to dio->bio.bi_status because we will only check dio->bio.bi_status when we return the whole IO to the upper layer. Fixes: 542ff7bf18c6 ("block: new direct I/O implementation") Cc: stable@vger.kernel.org Cc: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-10fs/block_dev.c: remove unused includeChengguang Xu1-1/+0
Just remove unused include <linux/badblocks.h> from fs/block_dev.c. Signed-off-by: Chengguang Xu <cgxu519@gmx.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-03-18block: add BIO_NO_PAGE_REF flagJens Axboe1-5/+7
If bio_iov_iter_get_pages() is called on an iov_iter that is flagged with NO_REF, then we don't need to add a page reference for the pages that we add. Add BIO_NO_PAGE_REF to track this in the bio, so IO completion knows not to drop a reference to these pages. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-24block: add bio_set_polled() helperJens Axboe1-2/+2
For the upcoming async polled IO, we can't sleep allocating requests. If we do, then we introduce a deadlock where the submitter already has async polled IO in-flight, but can't wait for them to complete since polled requests must be active found and reaped. Utilize the helper in the blockdev DIRECT_IO code. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-24block: wire up block device iopoll methodChristoph Hellwig1-1/+17
Just call blk_poll on the iocb cookie, we can derive the block device from the inode trivially. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-15block: allow bio_for_each_segment_all() to iterate over multi-page bvecMing Lei1-2/+4
This patch introduces one extra iterator variable to bio_for_each_segment_all(), then we can allow bio_for_each_segment_all() to iterate over multi-page bvec. Given it is just one mechannical & simple change on all bio_for_each_segment_all() users, this patch does tree-wide change in one single patch, so that we can avoid to use a temporary helper for this conversion. Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-01-15blockdev: Fix livelocks on loop deviceJan Kara1-10/+18
bd_set_size() updates also block device's block size. This is somewhat unexpected from its name and at this point, only blkdev_open() uses this functionality. Furthermore, this can result in changing block size under a filesystem mounted on a loop device which leads to livelocks inside __getblk_gfp() like: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10863 Comm: syz-executor0 Not tainted 4.18.0-rc5+ #151 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x50 kernel/kcov.c:106 ... Call Trace: init_page_buffers+0x3e2/0x530 fs/buffer.c:904 grow_dev_page fs/buffer.c:947 [inline] grow_buffers fs/buffer.c:1009 [inline] __getblk_slow fs/buffer.c:1036 [inline] __getblk_gfp+0x906/0xb10 fs/buffer.c:1313 __bread_gfp+0x2d/0x310 fs/buffer.c:1347 sb_bread include/linux/buffer_head.h:307 [inline] fat12_ent_bread+0x14e/0x3d0 fs/fat/fatent.c:75 fat_ent_read_block fs/fat/fatent.c:441 [inline] fat_alloc_clusters+0x8ce/0x16e0 fs/fat/fatent.c:489 fat_add_cluster+0x7a/0x150 fs/fat/inode.c:101 __fat_get_block fs/fat/inode.c:148 [inline] ... Trivial reproducer for the problem looks like: truncate -s 1G /tmp/image losetup /dev/loop0 /tmp/image mkfs.ext4 -b 1024 /dev/loop0 mount -t ext4 /dev/loop0 /mnt losetup -c /dev/loop0 l /mnt Fix the problem by moving initialization of a block device block size into a separate function and call it when needed. Thanks to Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> for help with debugging the problem. Reported-by: syzbot+9933e4476f365f5d5a1b@syzkaller.appspotmail.com Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-01-02block: don't use un-ordered __set_current_state(TASK_UNINTERRUPTIBLE)Linus Torvalds1-5/+2
This mostly reverts commit 849a370016a5 ("block: avoid ordered task state change for polled IO"). It was wrongly claiming that the ordering wasn't necessary. The memory barrier _is_ necessary. If something is truly polling and not going to sleep, it's the whole state setting that is unnecessary, not the memory barrier. Whenever you set your state to a sleeping state, you absolutely need the memory barrier. Note that sometimes the memory barrier can be elsewhere. For example, the ordering might be provided by an external lock, or by setting the process state to sleeping before adding yourself to the wait queue list that is used for waking up (where the wait queue lock itself will guarantee that any wakeup will correctly see the sleeping state). But none of those cases were true here. NOTE! Some of the polling paths may indeed be able to drop the state setting entirely, at which point the memory barrier also goes away. (Also note that this doesn't revert the TASK_RUNNING cases: there is no race between a wakeup and setting the process state to TASK_RUNNING, since the end result doesn't depend on ordering). Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-29Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+1
Merge misc updates from Andrew Morton: - large KASAN update to use arm's "software tag-based mode" - a few misc things - sh updates - ocfs2 updates - just about all of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (167 commits) kernel/fork.c: mark 'stack_vm_area' with __maybe_unused memcg, oom: notify on oom killer invocation from the charge path mm, swap: fix swapoff with KSM pages include/linux/gfp.h: fix typo mm/hmm: fix memremap.h, move dev_page_fault_t callback to hmm hugetlbfs: Use i_mmap_rwsem to fix page fault/truncate race hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization memory_hotplug: add missing newlines to debugging output mm: remove __hugepage_set_anon_rmap() include/linux/vmstat.h: remove unused page state adjustment macro mm/page_alloc.c: allow error injection mm: migrate: drop unused argument of migrate_page_move_mapping() blkdev: avoid migration stalls for blkdev pages mm: migrate: provide buffer_migrate_page_norefs() mm: migrate: move migrate_page_lock_buffers() mm: migrate: lock buffers before migrate_page_move_mapping() mm: migration: factor out code to compute expected number of page references mm, page_alloc: enable pcpu_drain with zone capability kmemleak: add config to select auto scan mm/page_alloc.c: don't call kasan_free_pages() at deferred mem init ...
2018-12-28blkdev: avoid migration stalls for blkdev pagesJan Kara1-0/+1
Currently, block device pages don't provide a ->migratepage callback and thus fallback_migrate_page() is used for them. This handler cannot deal with dirty pages in async mode and also with the case a buffer head is in the LRU buffer head cache (as it has elevated b_count). Thus such page can block memory offlining. Fix the problem by using buffer_migrate_page_norefs() for migrating block device pages. That function takes care of dropping bh LRU in case migration would fail due to elevated buffer refcount to avoid stalls and can also migrate dirty pages without writing them. Link: http://lkml.kernel.org/r/20181211172143.7358-6-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-30block: avoid extra bio reference for async O_DIRECTChristoph Hellwig1-4/+13
The bio referencing has a trick that doesn't do any actual atomic inc/dec on the reference count until we have to elevator to > 1. For the async IO O_DIRECT case, we can't use the simple DIO variants, so we use __blkdev_direct_IO(). It always grabs an extra reference to the bio after allocation, which means we then enter the slower path of actually having to do atomic_inc/dec on the count. We don't need to do that for the async case, unless we end up going multi-bio, in which case we're already doing huge amounts of IO. For the smaller IO case (< BIO_MAX_PAGES), we can do without the extra ref. Based on an earlier patch (and commit log) from Jens Axboe. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-26block: make blk_poll() take a parameter on whether to spin or notJens Axboe1-2/+2
blk_poll() has always kept spinning until it found an IO. This is fine for SYNC polling, since we need to find one request we have pending, but in preparation for ASYNC polling it can be beneficial to just check if we have any entries available or not. Existing callers are converted to pass in 'spin == true', to retain the old behavior. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-19block: avoid ordered task state change for polled IOJens Axboe1-2/+5
For the core poll helper, the task state setting don't need to imply any atomics, as it's the current task itself that is being modified and we're not going to sleep. For IRQ driven, the wakeup path have the necessary barriers to not need us using the heavy handed version of the task state setting. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-16block: don't plug for aio/O_DIRECT HIPRI IOJens Axboe1-2/+11
Those will go straight to issue inside blk-mq, so don't bother setting up a block plug for them. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-16block: for async O_DIRECT, mark us as polling if asked toJens Axboe1-0/+3
Inherit the iocb IOCB_HIPRI flag, and pass on REQ_HIPRI for those kinds of requests. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-16block: add polled wakeup task helperJens Axboe1-2/+2
If we're polling for IO on a device that doesn't use interrupts, then IO completion loop (and wake of task) is done by submitting task itself. If that is the case, then we don't need to enter the wake_up_process() function, we can simply mark ourselves as TASK_RUNNING. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-07block: add REQ_HIPRI and inherit it from IOCB_HIPRIJens Axboe1-0/+2
We use IOCB_HIPRI to poll for IO in the caller instead of scheduling. This information is not available for (or after) IO submission. The driver may make different queue choices based on the type of IO, so make the fact that we will poll for this IO known to the lower layers as well. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-24iov_iter: Use accessor functionDavid Howells1-1/+1
Use accessor functions to access an iterator's type and direction. This allows for the possibility of using some other method of determining the type of iterator than if-chains with bitwise-AND conditions. Signed-off-by: David Howells <dhowells@redhat.com>
2018-08-14Merge tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-blockLinus Torvalds1-2/+4
Pull block updates from Jens Axboe: "First pull request for this merge window, there will also be a followup request with some stragglers. This pull request contains: - Fix for a thundering heard issue in the wbt block code (Anchal Agarwal) - A few NVMe pull requests: * Improved tracepoints (Keith) * Larger inline data support for RDMA (Steve Wise) * RDMA setup/teardown fixes (Sagi) * Effects log suppor for NVMe target (Chaitanya Kulkarni) * Buffered IO suppor for NVMe target (Chaitanya Kulkarni) * TP4004 (ANA) support (Christoph) * Various NVMe fixes - Block io-latency controller support. Much needed support for properly containing block devices. (Josef) - Series improving how we handle sense information on the stack (Kees) - Lightnvm fixes and updates/improvements (Mathias/Javier et al) - Zoned device support for null_blk (Matias) - AIX partition fixes (Mauricio Faria de Oliveira) - DIF checksum code made generic (Max Gurtovoy) - Add support for discard in iostats (Michael Callahan / Tejun) - Set of updates for BFQ (Paolo) - Removal of async write support for bsg (Christoph) - Bio page dirtying and clone fixups (Christoph) - Set of bcache fix/changes (via Coly) - Series improving blk-mq queue setup/teardown speed (Ming) - Series improving merging performance on blk-mq (Ming) - Lots of other fixes and cleanups from a slew of folks" * tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-block: (190 commits) blkcg: Make blkg_root_lookup() work for queues in bypass mode bcache: fix error setting writeback_rate through sysfs interface null_blk: add lock drop/acquire annotation Blk-throttle: reduce tail io latency when iops limit is enforced block: paride: pd: mark expected switch fall-throughs block: Ensure that a request queue is dissociated from the cgroup controller block: Introduce blk_exit_queue() blkcg: Introduce blkg_root_lookup() block: Remove two superfluous #include directives blk-mq: count the hctx as active before allocating tag block: bvec_nr_vecs() returns value for wrong slab bcache: trivial - remove tailing backslash in macro BTREE_FLAG bcache: make the pr_err statement used for ENOENT only in sysfs_attatch section bcache: set max writeback rate when I/O request is idle bcache: add code comments for bset.c bcache: fix mistaken comments in request.c bcache: fix mistaken code comments in bcache.h bcache: add a comment in super.c bcache: avoid unncessary cache prefetch bch_btree_node_get() bcache: display rate debug parameters to 0 when writeback is not running ...
2018-07-27Merge tag 'for-linus-20180727' of git://git.kernel.dk/linux-blockLinus Torvalds1-4/+5
Pull block fixes from Jens Axboe: "Bigger than usual at this time, mostly due to the O_DIRECT corruption issue and the fact that I was on vacation last week. This contains: - NVMe pull request with two fixes for the FC code, and two target fixes (Christoph) - a DIF bio reset iteration fix (Greg Edwards) - two nbd reply and requeue fixes (Josef) - SCSI timeout fixup (Keith) - a small series that fixes an issue with bio_iov_iter_get_pages(), which ended up causing corruption for larger sized O_DIRECT writes that ended up racing with buffered writes (Martin Wilck)" * tag 'for-linus-20180727' of git://git.kernel.dk/linux-block: block: reset bi_iter.bi_done after splitting bio block: bio_iov_iter_get_pages: pin more pages for multi-segment IOs blkdev: __blkdev_direct_IO_simple: fix leak in error case block: bio_iov_iter_get_pages: fix size of last iovec nvmet: only check for filebacking on -ENOTBLK nvmet: fixup crash on NULL device path scsi: set timed out out mq requests to complete blk-mq: export setting request completion state nvme: if_ready checks to fail io to deleting controller nvmet-fc: fix target sgl list on large transfers nbd: handle unexpected replies better nbd: don't requeue the same request twice.
2018-07-26blkdev: __blkdev_direct_IO_simple: fix leak in error caseMartin Wilck1-4/+5
Fixes: 72ecad22d9f1 ("block: support a full bio worth of IO for simplified bdev direct-io") Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin Wilck <mwilck@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-18block: make bdev_ops->rw_page() take a REQ_OP instead of boolTejun Heo1-2/+4
c11f0c0b5bb9 ("block/mm: make bdev_ops->rw_page() take a bool for read/write") replaced @op with boolean @is_write, which limited the amount of information going into ->rw_page() and more importantly page_endio(), which removed the need to expose block internals to mm. Unfortunately, we want to track discards separately and @is_write isn't enough information. This patch updates bdev_ops->rw_page() to take REQ_OP instead but leaves page_endio() to take bool @is_write. This allows the block part of operations to have enough information while not leaking it to mm. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Mike Christie <mchristi@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-13treewide: kmalloc() -> kmalloc_array()Kees Cook1-1/+2
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-08Merge branch 'work.aio' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull aio iopriority support from Al Viro: "The rest of aio stuff for this cycle - Adam's aio ioprio series" * 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: aio ioprio use ioprio_check_cap ret val fs: aio ioprio add explicit block layer dependence fs: iomap dio set bio prio from kiocb prio fs: blkdev set bio prio from kiocb prio fs: Add aio iopriority support fs: Convert kiocb rw_hint from enum to u16 block: add ioprio_check_cap function
2018-05-31fs: blkdev set bio prio from kiocb prioAdam Manzanares1-0/+2
Now that kiocb has an ioprio field copy this over to the bio when it is created from the kiocb. Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-31fs: convert block_dev.c to bioset_init()Kent Overstreet1-6/+3
Convert block DIO code to embedded bio sets. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29block: don't print a message when the device went awayChristoph Hellwig1-5/+9
The information about a size change in this case just creates confusion. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>