Prior patches ensured that all bios are now associated with some blkg.
This now makes bio->bi_css unnecessary as blkg maintains a reference to
the blkcg already.
This patch removes the field bi_css and transfers corresponding uses to
access via bi_blkg.
Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pointer inode is being assigned but is never used hence it is redundant
and can be removed.
Cleans up clang warning:
warning: variable 'inode' set but not used [-Wunused-but-set-variable]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This change adds LOOP_SET_BLOCK_SIZE as one of the supported ioctls
in lo_compat_ioctl. It only takes an unsigned long argument, and
in practice a 32-bit value works fine.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-linus-20180608' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A few fixes for this merge window, where some of them should go in
sooner rather than later, hence a new pull this week. This pull
request contains:
- Set of NVMe fixes, mostly follow up cleanups/fixes to the queue
changes, but also teardown/removal and misc changes (Christop/Dan/
Johannes/Sagi/Steve).
- Two lightnvm fixes for issues that showed up in this window
(Colin/Wei).
- Failfast/driver flags inheritance for flush requests (Hannes).
- The md device put sanitization and fix (Kent).
- dm bio_set inheritance fix (me).
- nbd discard granularity fix (Josef).
- nbd consistency in command printing (Kevin).
- Loop recursion validation fix (Ted).
- Partition overlap check (Wang)"
[ .. and now my build is warning-free again thanks to the md fix - Linus ]
* tag 'for-linus-20180608' of git://git.kernel.dk/linux-block: (22 commits)
nvme: cleanup double shift issue
nvme-pci: make CMB SQ mod-param read-only
nvme-pci: unquiesce dead controller queues
nvme-pci: remove HMB teardown on reset
nvme-pci: queue creation fixes
nvme-pci: remove unnecessary completion doorbell check
nvme-pci: remove unnecessary nested locking
nvmet: filter newlines from user input
nvme-rdma: correctly check for target keyed sgl support
nvme: don't hold nvmf_transports_rwsem for more than transport lookups
nvmet: return all zeroed buffer when we can't find an active namespace
md: Unify mddev destruction paths
dm: use bioset_init_from_src() to copy bio_set
block: add bioset_init_from_src() helper
block: always set partition number to '0' in blk_partition_remap()
block: pass failfast and driver-specific flags to flush requests
nbd: set discard_alignment to the granularity
nbd: Consistently use request pointer in debug messages.
block: add verifier for cmdline partition
lightnvm: pblk: fix resource leak of invalid_bitmap
...
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
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Merge tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
- clean up how we pass around gfp_t and
blk_mq_req_flags_t (Christoph)
- prepare us to defer scheduler attach (Christoph)
- clean up drivers handling of bounce buffers (Christoph)
- fix timeout handling corner cases (Christoph/Bart/Keith)
- bcache fixes (Coly)
- prep work for bcachefs and some block layer optimizations (Kent).
- convert users of bio_sets to using embedded structs (Kent).
- fixes for the BFQ io scheduler (Paolo/Davide/Filippo)
- lightnvm fixes and improvements (Matias, with contributions from Hans
and Javier)
- adding discard throttling to blk-wbt (me)
- sbitmap blk-mq-tag handling (me/Omar/Ming).
- remove the sparc jsflash block driver, acked by DaveM.
- Kyber scheduler improvement from Jianchao, making it more friendly
wrt merging.
- conversion of symbolic proc permissions to octal, from Joe Perches.
Previously the block parts were a mix of both.
- nbd fixes (Josef and Kevin Vigor)
- unify how we handle the various kinds of timestamps that the block
core and utility code uses (Omar)
- three NVMe pull requests from Keith and Christoph, bringing AEN to
feature completeness, file backed namespaces, cq/sq lock split, and
various fixes
- various little fixes and improvements all over the map
* tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block: (196 commits)
blk-mq: update nr_requests when switching to 'none' scheduler
block: don't use blocking queue entered for recursive bio submits
dm-crypt: fix warning in shutdown path
lightnvm: pblk: take bitmap alloc. out of critical section
lightnvm: pblk: kick writer on new flush points
lightnvm: pblk: only try to recover lines with written smeta
lightnvm: pblk: remove unnecessary bio_get/put
lightnvm: pblk: add possibility to set write buffer size manually
lightnvm: fix partial read error path
lightnvm: proper error handling for pblk_bio_add_pages
lightnvm: pblk: fix smeta write error path
lightnvm: pblk: garbage collect lines with failed writes
lightnvm: pblk: rework write error recovery path
lightnvm: pblk: remove dead function
lightnvm: pass flag on graceful teardown to targets
lightnvm: pblk: check for chunk size before allocating it
lightnvm: pblk: remove unnecessary argument
lightnvm: pblk: remove unnecessary indirection
lightnvm: pblk: return NVM_ error on failed submission
lightnvm: pblk: warn in case of corrupted write buffer
...
This is the per-I/O equivalent of the ioprio_set system call.
When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the
newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field.
This patch depends on block: add ioprio_check_cap function.
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.
see: https://lkml.org/lkml/2016/8/2/1945
Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>
Miscellanea:
o Wrapped modified multi-line calls to a single line where appropriate
o Realign modified multi-line calls to open parenthesis
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a loop block device encounters a writeback error, that error will
get propagated to the bd_inode's wb_err field. If we then detach the
backing file from it, attach another and fsync it, we'll get back the
writeback error that we had from the previous backing file.
This is a bit of a grey area as POSIX doesn't cover loop devices, but it
is somewhat counterintuitive.
If we detach a backing file from the loopdev while there are still
unreported errors, take it as a sign that we're no longer interested in
the previous file, and clear out the wb_err in the loop blockdev.
Reported-and-Tested-by: Theodore Y. Ts'o <tytso@mit.edu>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We ran into an issue with loop and btrfs, where btrfs would complain about
checksum errors. It turns out that is because we don't handle short reads
at all, we just zero fill the remainder. Worse than that, we don't handle
the filling properly, which results in loop trying to advance a single
bio by much more than its size, since it doesn't take chaining into
account.
Handle short reads appropriately, by simply retrying at the new correct
offset. End the remainder of the request with EIO, if we get a 0 read.
Fixes: bc07c10a36 ("block: loop: support DIO & AIO")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We can always get at the request from the payload, no need to store
a pointer to it.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 2d1d4c1e59 made loop_get_status() drop lo_ctx_mutex before
returning, but the loop_get_status_old(), loop_get_status64(), and
loop_get_status_compat() wrappers don't call loop_get_status() if the
passed argument is NULL. The callers expect that the lock is dropped, so
make sure we drop it in that case, too.
Reported-by: syzbot+31e8daa8b3fc129e75f2@syzkaller.appspotmail.com
Fixes: 2d1d4c1e59 ("loop: don't call into filesystem while holding lo_ctl_mutex")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
"It's a pretty quiet round this time, which is nice. This contains:
- series from Bart, cleaning up the way we set/test/clear atomic
queue flags.
- series from Bart, fixing races between gendisk and queue
registration and removal.
- set of bcache fixes and improvements from various folks, by way of
Michael Lyle.
- set of lightnvm updates from Matias, most of it being the 1.2 to
2.0 transition.
- removal of unused DIO flags from Nikolay.
- blk-mq/sbitmap memory ordering fixes from Omar.
- divide-by-zero fix for BFQ from Paolo.
- minor documentation patches from Randy.
- timeout fix from Tejun.
- Alpha "can't write a char atomically" fix from Mikulas.
- set of NVMe fixes by way of Keith.
- bsg and bsg-lib improvements from Christoph.
- a few sed-opal fixes from Jonas.
- cdrom check-disk-change deadlock fix from Maurizio.
- various little fixes, comment fixes, etc from various folks"
* tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits)
blk-mq: Directly schedule q->timeout_work when aborting a request
blktrace: fix comment in blktrace_api.h
lightnvm: remove function name in strings
lightnvm: pblk: remove some unnecessary NULL checks
lightnvm: pblk: don't recover unwritten lines
lightnvm: pblk: implement 2.0 support
lightnvm: pblk: implement get log report chunk
lightnvm: pblk: rename ppaf* to addrf*
lightnvm: pblk: check for supported version
lightnvm: implement get log report chunk helpers
lightnvm: make address conversions depend on generic device
lightnvm: add support for 2.0 address format
lightnvm: normalize geometry nomenclature
lightnvm: complete geo structure with maxoc*
lightnvm: add shorten OCSSD version in geo
lightnvm: add minor version to generic geometry
lightnvm: simplify geometry structure
lightnvm: pblk: refactor init/exit sequences
lightnvm: Avoid validation of default op value
lightnvm: centralize permission check for lightnvm ioctl
...
Even after the previous patch to drop lo_ctl_mutex while calling
vfs_getattr(), there are other cases where we can end up sleeping for a
long time while holding lo_ctl_mutex. Let's avoid the uninterruptible
sleep from the ioctls.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We hit an issue where a loop device on NFS was stuck in
loop_get_status() doing vfs_getattr() after the NFS server died, which
caused a pile-up of uninterruptible processes waiting on lo_ctl_mutex.
There's no reason to hold this lock while we wait on the filesystem;
let's drop it so that other processes can do their thing. We need to
grab a reference on lo_backing_file while we use it, and we can get rid
of the check on lo_device, which has been unnecessary since commit
a34c0ae9ebd6 ("[PATCH] loop: remove the bio remapping capability") in
the linux-history tree.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The following commit:
commit aa4d86163e ("block: loop: switch to VFS ITER_BVEC")
replaced __do_lo_send_write(), which used ITER_KVEC iterators, with
lo_write_bvec() which uses ITER_BVEC iterators. In this change, though,
the WRITE flag was lost:
- iov_iter_kvec(&from, ITER_KVEC | WRITE, &kvec, 1, len);
+ iov_iter_bvec(&i, ITER_BVEC, bvec, 1, bvec->bv_len);
This flag is necessary for the DAX case because we make decisions based on
whether or not the iterator is a READ or a WRITE in dax_iomap_actor() and
in dax_iomap_rw().
We end up going through this path in configurations where we combine a PMEM
device with 4k sectors, a loopback device and DAX. The consequence of this
missed flag is that what we intend as a write actually turns into a read in
the DAX code, so no data is ever written.
The very simplest test case is to create a loopback device and try and
write a small string to it, then hexdump a few bytes of the device to see
if the write took. Without this patch you read back all zeros, with this
you read back the string you wrote.
For XFS this causes us to fail or panic during the following xfstests:
xfs/074 xfs/078 xfs/216 xfs/217 xfs/250
For ext4 we have a similar issue where writes never happen, but we don't
currently have any xfstests that use loopback and show this issue.
Fix this by restoring the WRITE flag argument to iov_iter_bvec(). This
causes the xfstests to all pass.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Fixes: commit aa4d86163e ("block: loop: switch to VFS ITER_BVEC")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch has been generated as follows:
for verb in set_unlocked clear_unlocked set clear; do
replace-in-files queue_flag_${verb} blk_queue_flag_${verb%_unlocked} \
$(git grep -lw queue_flag_${verb} drivers block/bsg*)
done
Except for protecting all queue flag changes with the queue lock
this patch does not change any functionality.
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove the disk, partition and bdi sysfs attributes before cleaning up
the request queue associated with the disk.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rename get_disk() to get_disk_and_module() to make sure what the
function does. It's not a great name but at least it is now clear that
put_disk() is not it's counterpart.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
范龙飞 reports that KASAN can report a use-after-free in __lock_acquire.
The reason is due to insufficient serialization in lo_release(), which
will continue to use the loop device even after it has decremented the
lo_refcnt to zero.
In the meantime, another process can come in, open the loop device
again as it is being shut down. Confusion ensues.
Reported-by: 范龙飞 <long7573@126.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The code is only for blkcg not for all cgroups
Fixes: d4478e92d6 ("block/loop: make loop cgroup aware")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
loop block device handles IO in a separate thread. The actual IO
dispatched isn't cloned from the IO loop device received, so the
dispatched IO loses the cgroup context.
I'm ignoring buffer IO case now, which is quite complicated. Making the
loop thread aware cgroup context doesn't really help. The loop device
only writes to a single file. In current writeback cgroup
implementation, the file can only belong to one cgroup.
For direct IO case, we could workaround the issue in theory. For
example, say we assign cgroup1 5M/s BW for loop device and cgroup2
10M/s. We can create a special cgroup for loop thread and assign at
least 15M/s for the underlayer disk. In this way, we correctly throttle
the two cgroups. But this is tricky to setup.
This patch tries to address the issue. We record bio's css in loop
command. When loop thread is handling the command, we then use the API
provided in patch 1 to set the css for current task. The bio layer will
use the css for new IO (from patch 3).
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 6c6b6f28b3 ("loop: set physical block size to PAGE_SIZE")
caused mkfs.xfs to barf on ppc64 [1]. Always using PAGE_SIZE as the
physical block size still makes the most sense semantically, but let's
just lie and always set it to the same value as the logical block size
(same goes for io_min). In the future we might want to at least bump up
io_min to PAGE_SIZE but I'm sick of these stupid changes so let's play
it safe.
1: https://marc.info/?l=linux-xfs&m=150459024723753&w=2
Tested-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
lo_rw_aio->call_read_iter->
1 aops->direct_IO
2 iov_iter_revert
lo_rw_aio_complete could happen between 1 and 2, the bio and bvec could
be freed before 2, which accesses bvec.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently loop disables merge. While it makes sense for buffer IO mode,
directio mode can benefit from request merge. Without merge, loop could
send small size IO to underlayer disk and harm performance.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Loop can handle any size of request. Limiting it to 255 sectors just
burns the CPU for bio split and request merge for underlayer disk and
also cause bad fs block allocation in directio mode.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The comments here are really outdated, and blk-mq made flushing much
simpler, so just fold the two cases into the callers.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is a different approach from the first attempt in f2c6df7dbf
("loop: support 4k physical blocksize"). Rather than extending
LOOP_{GET,SET}_STATUS, add a separate ioctl just for setting the block
size.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The physical block size is "the lowest possible sector size that the
hardware can operate on without reverting to read-modify-write
operations" (from the comment on blk_queue_physical_block_size()). Since
loop does buffered I/O on the backing file by default, the RMW unit is a
page. This isn't the case for direct I/O mode, but let's keep it simple.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is only used for setting the soft block size on the struct
block_device once and then never used again.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There's some stuff still up in the air, let's not get stuck with a
subpar ABI. I'll follow up with something better for 4.14.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The early device registration made possible a race leading to allocations
of disks with wrong minors.
This patch moves the device registration further down the loop_init
function to make the race infeasible.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Anton Volkov <avolkov@ispras.ru>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull read/write updates from Al Viro:
"Christoph's fs/read_write.c series - consolidation and cleanups"
* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
nfsd: remove nfsd_vfs_read
nfsd: use vfs_iter_read/write
fs: implement vfs_iter_write using do_iter_write
fs: implement vfs_iter_read using do_iter_read
fs: move more code into do_iter_read/do_iter_write
fs: remove __do_readv_writev
fs: remove do_compat_readv_writev
fs: remove do_readv_writev
De-dupliate some code and allow for passing the flags argument to
vfs_iter_write. Additionally it now properly updates timestamps.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
De-dupliate some code and allow for passing the flags argument to
vfs_iter_read. Additional it properly updates atime now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When a filesystem is mounted from a loop device, writes are
throttled by balance_dirty_pages() twice: once when writing
to the filesystem and once when the loop_handle_cmd() writes
to the backing file. This double-throttling can trigger
positive feedback loops that create significant delays. The
throttling at the lower level is seen by the upper level as
a slow device, so it throttles extra hard.
The PF_LESS_THROTTLE flag was created to handle exactly this
circumstance, though with an NFS filesystem mounted from a
local NFS server. It reduces the throttling on the lower
layer so that it can proceed largely unthrottled.
To demonstrate this, create a filesystem on a loop device
and write (e.g. with dd) several large files which combine
to consume significantly more than the limit set by
/proc/sys/vm/dirty_ratio or dirty_bytes. Measure the total
time taken.
When I do this directly on a device (no loop device) the
total time for several runs (mkfs, mount, write 200 files,
umount) is fairly stable: 28-35 seconds.
When I do this over a loop device the times are much worse
and less stable. 52-460 seconds. Half below 100seconds,
half above.
When I apply this patch, the times become stable again,
though not as fast as the no-loop-back case: 53-72 seconds.
There may be room for further improvement as the total overhead still
seems too high, but this is a big improvement.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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Merge tag 'v4.12-rc5' into for-4.13/block
We've already got a few conflicts and upcoming work depends on some of the
changes that have gone into mainline as regression fixes for this series.
Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream
trees to continue working on 4.13 changes.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use the same values for use for request completion errors as the return
value from ->queue_rq. BLK_STS_RESOURCE is special cased to cause
a requeue, and all the others are completed as-is.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently we use nornal Linux errno values in the block layer, and while
we accept any error a few have overloaded magic meanings. This patch
instead introduces a new blk_status_t value that holds block layer specific
status codes and explicitly explains their meaning. Helpers to convert from
and to the previous special meanings are provided for now, but I suspect
we want to get rid of them in the long run - those drivers that have a
errno input (e.g. networking) usually get errnos that don't know about
the special block layer overloads, and similarly returning them to userspace
will usually return somethings that strictly speaking isn't correct
for file system operations, but that's left as an exercise for later.
For now the set of errors is a very limited set that closely corresponds
to the previous overloaded errno values, but there is some low hanging
fruite to improve it.
blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse
typechecking, so that we can easily catch places passing the wrong values.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
gcc points out an unusual indentation:
drivers/block/loop.c: In function 'loop_set_status':
drivers/block/loop.c:1149:3: error: this 'if' clause does not guard... [-Werror=misleading-indentation]
if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit,
^~
drivers/block/loop.c:1152:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
goto exit;
This was introduced by a new feature that accidentally moved the opening
braces from one condition to another. Adding a second pair of braces
makes it work correctly again and also more readable.
Fixes: f2c6df7dbf ("loop: support 4k physical blocksize")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
When generating bootable VM images certain systems (most notably
s390x) require devices with 4k blocksize. This patch implements
a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
blocksize to that of the underlying device, and allow to change
the logical blocksize for up to the physical blocksize.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
While installing SLES-12 (based on v4.4), I found that the installer
will stall for 60+ seconds during LVM disk scan. The root cause was
determined to be the removal of a bound device check in loop_flush()
by commit b5dd2f6047 ("block: loop: improve performance via blk-mq").
Restoring this check, examining ->lo_state as set by loop_set_fd()
eliminates the bad behavior.
Test method:
modprobe loop max_loop=64
dd if=/dev/zero of=disk bs=512 count=200K
for((i=0;i<4;i++))do losetup -f disk; done
mkfs.ext4 -F /dev/loop0
for((i=0;i<4;i++))do mkdir t$i; mount /dev/loop$i t$i;done
for f in `ls /dev/loop[0-9]*|sort`; do \
echo $f; dd if=$f of=/dev/null bs=512 count=1; \
done
Test output: stock patched
/dev/loop0 18.1217e-05 8.3842e-05
/dev/loop1 6.1114e-05 0.000147979
/dev/loop10 0.414701 0.000116564
/dev/loop11 0.7474 6.7942e-05
/dev/loop12 0.747986 8.9082e-05
/dev/loop13 0.746532 7.4799e-05
/dev/loop14 0.480041 9.3926e-05
/dev/loop15 1.26453 7.2522e-05
Note that from loop10 onward, the device is not mounted, yet the
stock kernel consumes several orders of magnitude more wall time
than it does for a mounted device.
(Thanks for Mike Galbraith <efault@gmx.de>, give a changelog review.)
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: James Wang <jnwang@suse.com>
Fixes: b5dd2f6047 ("block: loop: improve performance via blk-mq")
Signed-off-by: Jens Axboe <axboe@fb.com>
