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2014-05-22Merge tag 'v3.15-rc6' into sched/core, to pick up the latest fixesIngo Molnar1-4/+7
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07Merge branch 'sched/urgent' into sched/core, to avoid conflictsIngo Molnar17-481/+1388
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-05floppy: don't write kernel-only members to FDRAWCMD ioctl outputMatthew Daley1-1/+4
Do not leak kernel-only floppy_raw_cmd structure members to userspace. This includes the linked-list pointer and the pointer to the allocated DMA space. Signed-off-by: Matthew Daley <mattd@bugfuzz.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-05-05floppy: ignore kernel-only members in FDRAWCMD ioctl inputMatthew Daley1-3/+3
Always clear out these floppy_raw_cmd struct members after copying the entire structure from userspace so that the in-kernel version is always valid and never left in an interdeterminate state. Signed-off-by: Matthew Daley <mattd@bugfuzz.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-18sched, treewide: Replace hardcoded nice values with MIN_NICE/MAX_NICEDongsheng Yang3-3/+3
Replace various -20/+19 hardcoded nice values with MIN_NICE/MAX_NICE. Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/ff13819fd09b7a5dba5ab5ae797f2e7019bdfa17.1394532288.git.yangds.fnst@cn.fujitsu.com Cc: devel@driverdev.osuosl.org Cc: devicetree@vger.kernel.org Cc: fcoe-devel@open-fcoe.org Cc: linux390@de.ibm.com Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-s390@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: nbd-general@lists.sourceforge.net Cc: ocfs2-devel@oss.oracle.com Cc: openipmi-developer@lists.sourceforge.net Cc: qla2xxx-upstream@qlogic.com Cc: linux-arch@vger.kernel.org [ Consolidated the patches, twiddled the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-12Merge branch 'for-linus' of ↵Linus Torvalds2-40/+20
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "The first vfs pile, with deep apologies for being very late in this window. Assorted cleanups and fixes, plus a large preparatory part of iov_iter work. There's a lot more of that, but it'll probably go into the next merge window - it *does* shape up nicely, removes a lot of boilerplate, gets rid of locking inconsistencie between aio_write and splice_write and I hope to get Kent's direct-io rewrite merged into the same queue, but some of the stuff after this point is having (mostly trivial) conflicts with the things already merged into mainline and with some I want more testing. This one passes LTP and xfstests without regressions, in addition to usual beating. BTW, readahead02 in ltp syscalls testsuite has started giving failures since "mm/readahead.c: fix readahead failure for memoryless NUMA nodes and limit readahead pages" - might be a false positive, might be a real regression..." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) missing bits of "splice: fix racy pipe->buffers uses" cifs: fix the race in cifs_writev() ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure kill generic_file_buffered_write() ocfs2_file_aio_write(): switch to generic_perform_write() ceph_aio_write(): switch to generic_perform_write() xfs_file_buffered_aio_write(): switch to generic_perform_write() export generic_perform_write(), start getting rid of generic_file_buffer_write() generic_file_direct_write(): get rid of ppos argument btrfs_file_aio_write(): get rid of ppos kill the 5th argument of generic_file_buffered_write() kill the 4th argument of __generic_file_aio_write() lustre: don't open-code kernel_recvmsg() ocfs2: don't open-code kernel_recvmsg() drbd: don't open-code kernel_recvmsg() constify blk_rq_map_user_iov() and friends lustre: switch to kernel_sendmsg() ocfs2: don't open-code kernel_sendmsg() take iov_iter stuff to mm/iov_iter.c process_vm_access: tidy up a bit ...
2014-04-11Merge git://git.infradead.org/users/willy/linux-nvmeLinus Torvalds2-236/+491
Pull NVMe driver updates from Matthew Wilcox: "Various updates to the NVMe driver. The most user-visible change is that drive hotplugging now works and CPU hotplug while an NVMe drive is installed should also work better" * git://git.infradead.org/users/willy/linux-nvme: NVMe: Retry failed commands with non-fatal errors NVMe: Add getgeo to block ops NVMe: Start-stop nvme_thread during device add-remove. NVMe: Make I/O timeout a module parameter NVMe: CPU hot plug notification NVMe: per-cpu io queues NVMe: Replace DEFINE_PCI_DEVICE_TABLE NVMe: Fix divide-by-zero in nvme_trans_io_get_num_cmds NVMe: IOCTL path RCU protect queue access NVMe: RCU protected access to io queues NVMe: Initialize device reference count earlier NVMe: Add CONFIG_PM_SLEEP to suspend/resume functions
2014-04-10NVMe: Retry failed commands with non-fatal errorsKeith Busch2-94/+151
For commands returned with failed status, queue these for resubmission and continue retrying them until success or for a limited amount of time. The final timeout was arbitrarily chosen so requests can't be retried indefinitely. Since these are requeued on the nvmeq that submitted the command, the callbacks have to take an nvmeq instead of an nvme_dev as a parameter so that we can use the locked queue to append the iod to retry later. The nvme_iod conviently can be used to track how long we've been trying to successfully complete an iod request. The nvme_iod also provides the nvme prp dma mappings, so I had to move a few things around so we can keep those mappings. Signed-off-by: Keith Busch <keith.busch@intel.com> [fixed checkpatch issue with long line] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2014-04-10NVMe: Add getgeo to block opsKeith Busch1-0/+11
Some programs require HDIO_GETGEO work, which requires we implement getgeo. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2014-04-10NVMe: Start-stop nvme_thread during device add-remove.Dan McLeran1-14/+42
Done to ensure nvme_thread is not running when there are no devices to poll. Signed-off-by: Dan McLeran <daniel.mcleran@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2014-04-10NVMe: Make I/O timeout a module parameterKeith Busch1-0/+4
Increase the default timeout to 30 seconds to match SCSI. Signed-off-by: Keith Busch <keith.busch@intel.com> [use byte instead of ushort] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2014-04-10NVMe: CPU hot plug notificationKeith Busch1-0/+19
Registers with hot cpu notification to rebalance, and potentially allocate additional, io queues. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2014-04-10NVMe: per-cpu io queuesKeith Busch1-37/+167
The device's IO queues are associated with CPUs, so we can use a per-cpu variable to map the a qid to a cpu. This provides a convienient way to optimally assign queues to multiple cpus when the device supports fewer queues than the host has cpus. The previous implementation may have assigned these poorly in these situations. This patch addresses this by sharing queues among cpus that are "close" together and should have a lower lock contention penalty. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2014-04-10Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds1-4/+4
Pull block layer fixes from Jens Axboe: "A small collection of fixes that should go in before -rc1. The pull request contains: - A two patch fix for a regression with block enabled tagging caused by a commit in the initial pull request. One patch is from Martin and ensures that SCSI doesn't truncate 64-bit block flags, the other one is from me and prevents us from double using struct request queuelist for both completion and busy tags. This caused anything from a boot crash for some, to crashes under load. - A blk-mq fix for a potential soft stall when hot unplugging CPUs with busy IO. - percpu_counter fix is listed in here, that caused a suspend issue with virtio-blk due to percpu counters having an inconsistent state during CPU removal. Andrew sent this in separately a few days ago, but it's here. JFYI. - A few fixes for block integrity from Martin. - A ratelimit fix for loop from Mike Galbraith, to avoid spewing too much in error cases" * 'for-linus' of git://git.kernel.dk/linux-block: block: fix regression with block enabled tagging scsi: Make sure cmd_flags are 64-bit block: Ensure we only enable integrity metadata for reads and writes block: Fix integrity verification block: Fix for_each_bvec() drivers/block/loop.c: ratelimit error messages blk-mq: fix potential stall during CPU unplug with IO pending percpu_counter: fix bad counter state during suspend
2014-04-08drivers/block/loop.c: ratelimit error messagesMike Galbraith1-4/+4
Metric tons of high speed spew is not helpful when things go pear shaped. systemd lost its mind, forgot how to stop services it insists on being sole manager of, massive printk() flood ensued, box eventually died. [16206.684000] loop: Write error at byte offset 11412291584, length 4096. [16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost. [16206.684000] loop: Write error at byte offset 13155434496, length 4096. [16206.684000] loop: Write error at byte offset 13155438592, length 4096. [16206.684000] loop: Write error at byte offset 13155442688, length 4096. [16206.684000] loop: Write error at byte offset 13960736768, length 4096. [16206.684000] loop: Write error at byte offset 14229172224, length 4096. [16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost. [16206.684000] loop: Write error at byte offset 14766043136, length 4096. [16206.684000] loop: Write error at byte offset 15034478592, length 4096. [16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost. Signed-off-by: Mike Galbraith <bitbucket@online.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-07Merge branch 'akpm' (incoming from Andrew)Linus Torvalds10-170/+797
Merge second patch-bomb from Andrew Morton: - the rest of MM - zram updates - zswap updates - exit - procfs - exec - wait - crash dump - lib/idr - rapidio - adfs, affs, bfs, ufs - cris - Kconfig things - initramfs - small amount of IPC material - percpu enhancements - early ioremap support - various other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (156 commits) MAINTAINERS: update Intel C600 SAS driver maintainers fs/ufs: remove unused ufs_super_block_third pointer fs/ufs: remove unused ufs_super_block_second pointer fs/ufs: remove unused ufs_super_block_first pointer fs/ufs/super.c: add __init to init_inodecache() doc/kernel-parameters.txt: add early_ioremap_debug arm64: add early_ioremap support arm64: initialize pgprot info earlier in boot x86: use generic early_ioremap mm: create generic early_ioremap() support x86/mm: sparse warning fix for early_memremap lglock: map to spinlock when !CONFIG_SMP percpu: add preemption checks to __this_cpu ops vmstat: use raw_cpu_ops to avoid false positives on preemption checks slub: use raw_cpu_inc for incrementing statistics net: replace __this_cpu_inc in route.c with raw_cpu_inc modules: use raw_cpu_write for initialization of per cpu refcount. mm: use raw_cpu ops for determining current NUMA node percpu: add raw_cpu_ops slub: fix leak of 'name' in sysfs_slab_add ...
2014-04-07zram: support REQ_DISCARDJoonsoo Kim1-0/+62
zram is ram based block device and can be used by backend of filesystem. When filesystem deletes a file, it normally doesn't do anything on data block of that file. It just marks on metadata of that file. This behavior has no problem on disk based block device, but has problems on ram based block device, since we can't free memory used for data block. To overcome this disadvantage, there is REQ_DISCARD functionality. If block device support REQ_DISCARD and filesystem is mounted with discard option, filesystem sends REQ_DISCARD to block device whenever some data blocks are discarded. All we have to do is to handle this request. This patch implements to flag up QUEUE_FLAG_DISCARD and handle this REQ_DISCARD request. With it, we can free memory used by zram if it isn't used. [akpm@linux-foundation.org: tweak comments] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: use scnprintf() in attrs show() methodsSergey Senozhatsky2-9/+11
sysfs.txt documentation lists the following requirements: - The buffer will always be PAGE_SIZE bytes in length. On i386, this is 4096. - show() methods should return the number of bytes printed into the buffer. This is the return value of scnprintf(). - show() should always use scnprintf(). Use scnprintf() in show() functions. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: propagate error to userMinchan Kim3-11/+20
When we initialized zcomp with single, we couldn't change max_comp_streams without zram reset but current interface doesn't show any error to user and even it changes max_comp_streams's value without any effect so it would make user very confusing. This patch prevents max_comp_streams's change when zcomp was initialized as single zcomp and emit the error to user(ex, echo). [akpm@linux-foundation.org: don't return with the lock held, per Sergey] [fengguang.wu@intel.com: fix coccinelle warnings] Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: return error-valued pointer from zcomp_create()Sergey Senozhatsky2-15/+18
Instead of returning just NULL, return ERR_PTR from zcomp_create() if compressing backend creation has failed. ERR_PTR(-EINVAL) for unsupported compression algorithm request, ERR_PTR(-ENOMEM) for allocation (zcomp or compression stream) error. Perform IS_ERR() check of returned from zcomp_create() value in disksize_store() and set return code to PTR_ERR(). Change suggested by Jerome Marchand. [akpm@linux-foundation.org: clean up error recovery flow] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Jerome Marchand <jmarchan@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: move comp allocation out of init_lockSergey Senozhatsky1-12/+15
While fixing lockdep spew of ->init_lock reported by Sasha Levin [1], Minchan Kim noted [2] that it's better to move compression backend allocation (using GPF_KERNEL) out of the ->init_lock lock, same way as with zram_meta_alloc(), in order to prevent the same lockdep spew. [1] https://lkml.org/lkml/2014/2/27/337 [2] https://lkml.org/lkml/2014/3/3/32 Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Minchan Kim <minchan@kernel.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Acked-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: add lz4 algorithm backendSergey Senozhatsky5-0/+82
Introduce LZ4 compression backend and make it available for selection. LZ4 support is optional and requires user to set ZRAM_LZ4_COMPRESS config option. The default compression backend is LZO. TEST (x86_64, core i5, 2 cores + 2 hyperthreading, zram disk size 1G, ext4 file system, 3 compression streams) iozone -t 3 -R -r 16K -s 60M -I +Z Test LZO LZ4 ---------------------------------------------- Initial write 1642744.62 1317005.09 Rewrite 2498980.88 1800645.16 Read 3957026.38 5877043.75 Re-read 3950997.38 5861847.00 Reverse Read 2937114.56 5047384.00 Stride read 2948163.19 4929587.38 Random read 3292692.69 4880793.62 Mixed workload 1545602.62 3502940.38 Random write 2448039.75 1758786.25 Pwrite 1670051.03 1338329.69 Pread 2530682.00 5097177.62 Fwrite 3232085.62 3275942.56 Fread 6306880.25 6645271.12 So on my system LZ4 is slower in write-only tests, while it performs better in read-only and mixed (reads + writes) tests. Official LZ4 benchmarks available here http://code.google.com/p/lz4/ (linux kernel uses revision r90). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: make compression algorithm selection possibleSergey Senozhatsky4-6/+66
Add and document `comp_algorithm' device attribute. This attribute allows to show supported compression and currently selected compression algorithms: cat /sys/block/zram0/comp_algorithm [lzo] lz4 and change selected compression algorithm: echo lzo > /sys/block/zram0/comp_algorithm Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: add set_max_streams knobSergey Senozhatsky3-3/+41
This patch allows to change max_comp_streams on initialised zcomp. Introduce zcomp set_max_streams() knob, zcomp_strm_multi_set_max_streams() and zcomp_strm_single_set_max_streams() callbacks to change streams limit for zcomp_strm_multi and zcomp_strm_single, accordingly. set_max_streams for single steam zcomp does nothing. If user has lowered the limit, then zcomp_strm_multi_set_max_streams() attempts to immediately free extra streams (as much as it can, depending on idle streams availability). Note, this patch does not allow to change stream 'policy' from single to multi stream (or vice versa) on already initialised compression backend. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: add multi stream functionalitySergey Senozhatsky4-5/+167
Existing zram (zcomp) implementation has only one compression stream (buffer and algorithm private part), so in order to prevent data corruption only one write (compress operation) can use this compression stream, forcing all concurrent write operations to wait for stream lock to be released. This patch changes zcomp to keep a compression streams list of user-defined size (via sysfs device attr). Each write operation still exclusively holds compression stream, the difference is that we can have N write operations (depending on size of streams list) executing in parallel. See TEST section later in commit message for performance data. Introduce struct zcomp_strm_multi and a set of functions to manage zcomp_strm stream access. zcomp_strm_multi has a list of idle zcomp_strm structs, spinlock to protect idle list and wait queue, making it possible to perform parallel compressions. The following set of functions added: - zcomp_strm_multi_find()/zcomp_strm_multi_release() find and release a compression stream, implement required locking - zcomp_strm_multi_create()/zcomp_strm_multi_destroy() create and destroy zcomp_strm_multi zcomp ->strm_find() and ->strm_release() callbacks are set during initialisation to zcomp_strm_multi_find()/zcomp_strm_multi_release() correspondingly. Each time zcomp issues a zcomp_strm_multi_find() call, the following set of operations performed: - spin lock strm_lock - if idle list is not empty, remove zcomp_strm from idle list, spin unlock and return zcomp stream pointer to caller - if idle list is empty, current adds itself to wait queue. it will be awaken by zcomp_strm_multi_release() caller. zcomp_strm_multi_release(): - spin lock strm_lock - add zcomp stream to idle list - spin unlock, wake up sleeper Minchan Kim reported that spinlock-based locking scheme has demonstrated a severe perfomance regression for single compression stream case, comparing to mutex-based (see https://lkml.org/lkml/2014/2/18/16) base spinlock mutex ==Initial write ==Initial write ==Initial write records: 5 records: 5 records: 5 avg: 1642424.35 avg: 699610.40 avg: 1655583.71 std: 39890.95(2.43%) std: 232014.19(33.16%) std: 52293.96 max: 1690170.94 max: 1163473.45 max: 1697164.75 min: 1568669.52 min: 573429.88 min: 1553410.23 ==Rewrite ==Rewrite ==Rewrite records: 5 records: 5 records: 5 avg: 1611775.39 avg: 501406.64 avg: 1684419.11 std: 17144.58(1.06%) std: 15354.41(3.06%) std: 18367.42 max: 1641800.95 max: 531356.78 max: 1706445.84 min: 1593515.27 min: 488817.78 min: 1655335.73 When only one compression stream available, mutex with spin on owner tends to perform much better than frequent wait_event()/wake_up(). This is why single stream implemented as a special case with mutex locking. Introduce and document zram device attribute max_comp_streams. This attr shows and stores current zcomp's max number of zcomp streams (max_strm). Extend zcomp's zcomp_create() with `max_strm' parameter. `max_strm' limits the number of zcomp_strm structs in compression backend's idle list (max_comp_streams). max_comp_streams used during initialisation as follows: -- passing to zcomp_create() max_strm equals to 1 will initialise zcomp using single compression stream zcomp_strm_single (mutex-based locking). -- passing to zcomp_create() max_strm greater than 1 will initialise zcomp using multi compression stream zcomp_strm_multi (spinlock-based locking). default max_comp_streams value is 1, meaning that zram with single stream will be initialised. Later patch will introduce configuration knob to change max_comp_streams on already initialised and used zcomp. TEST iozone -t 3 -R -r 16K -s 60M -I +Z test base 1 strm (mutex) 3 strm (spinlock) ----------------------------------------------------------------------- Initial write 589286.78 583518.39 718011.05 Rewrite 604837.97 596776.38 1515125.72 Random write 584120.11 595714.58 1388850.25 Pwrite 535731.17 541117.38 739295.27 Fwrite 1418083.88 1478612.72 1484927.06 Usage example: set max_comp_streams to 4 echo 4 > /sys/block/zram0/max_comp_streams show current max_comp_streams (default value is 1). cat /sys/block/zram0/max_comp_streams Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: factor out single stream compressionSergey Senozhatsky2-10/+59
This is preparation patch to add multi stream support to zcomp. Introduce struct zcomp_strm_single and a set of functions to manage zcomp_strm stream access. zcomp_strm_single implements single compession stream, same way as current zcomp implementation. This moves zcomp_strm stream control and locking from zcomp, so compressing backend zcomp is not aware of required locking. Single and multi streams require different locking schemes. Minchan Kim reported that spinlock-based locking scheme (which is used in multi stream implementation) has demonstrated a severe perfomance regression for single compression stream case, comparing to mutex-based. see https://lkml.org/lkml/2014/2/18/16 The following set of functions added: - zcomp_strm_single_find()/zcomp_strm_single_release() find and release a compression stream, implement required locking - zcomp_strm_single_create()/zcomp_strm_single_destroy() create and destroy zcomp_strm_single New ->strm_find() and ->strm_release() callbacks added to zcomp, which are set to zcomp_strm_single_find() and zcomp_strm_single_release() during initialisation. Instead of direct locking and zcomp_strm access from zcomp_strm_find() and zcomp_strm_release(), zcomp now calls ->strm_find() and ->strm_release() correspondingly. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: use zcomp compressing backendsSergey Senozhatsky3-43/+36
Do not perform direct LZO compress/decompress calls, initialise and use zcomp LZO backend (single compression stream) instead. [akpm@linux-foundation.org: resolve conflicts with zram-delete-zram_init_device-fix.patch] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: introduce compressing backend abstractionSergey Senozhatsky4-0/+237
ZRAM performs direct LZO compression algorithm calls, making it the one and only option. While LZO is generally performs well, LZ4 algorithm tends to have a faster decompression (see http://code.google.com/p/lz4/ for full report) Name Ratio C.speed D.speed MB/s MB/s LZ4 (r101) 2.084 422 1820 LZO 2.06 2.106 414 600 Thus, users who have mostly read (decompress) usage scenarious or mixed workflow (writes with relatively high read ops number) will benefit from using LZ4 compression backend. Introduce compressing backend abstraction zcomp in order to support multiple compression algorithms with the following set of operations: .create .destroy .compress .decompress Schematically zram write() usually contains the following steps: 0) preparation (decompression of partioal IO, etc.) 1) lock buffer_lock mutex (protects meta compress buffers) 2) compress (using meta compress buffers) 3) alloc and map zs_pool object 4) copy compressed data (from meta compress buffers) to object allocated by 3) 5) free previous pool page, assign a new one 6) unlock buffer_lock mutex As we can see, compressing buffers must remain untouched from 1) to 4), because, otherwise, concurrent write() can overwrite data. At the same time, zram_meta must be aware of a) specific compression algorithm memory requirements and b) necessary locking to protect compression buffers. To remove requirement a) new struct zcomp_strm introduced, which contains a compress/decompress `buffer' and compression algorithm `private' part. While struct zcomp implements zcomp_strm stream handling and locking and removes requirement b) from zram meta. zcomp ->create() and ->destroy(), respectively, allocate and deallocate algorithm specific zcomp_strm `private' part. Every zcomp has zcomp stream and mutex to protect its compression stream. Stream usage semantics remains the same -- only one write can hold stream lock and use its buffers. zcomp_strm_find() turns caller into exclusive user of a stream (holding stream mutex until zram release stream), and zcomp_strm_release() makes zcomp stream available (unlock the stream mutex). Hence no concurrent write (compression) operations possible at the moment. iozone -t 3 -R -r 16K -s 60M -I +Z test base patched -------------------------------------------------- Initial write 597992.91 591660.58 Rewrite 609674.34 616054.97 Read 2404771.75 2452909.12 Re-read 2459216.81 2470074.44 Reverse Read 1652769.66 1589128.66 Stride read 2202441.81 2202173.31 Random read 2236311.47 2276565.31 Mixed workload 1423760.41 1709760.06 Random write 579584.08 615933.86 Pwrite 597550.02 594933.70 Pread 1703672.53 1718126.72 Fwrite 1330497.06 1461054.00 Fread 3922851.00 3957242.62 Usage examples: comp = zcomp_create(NAME) /* NAME e.g. "lzo" */ which initialises compressing backend if requested algorithm is supported. Compress: zstrm = zcomp_strm_find(comp) zcomp_compress(comp, zstrm, src, &dst_len) [..] /* copy compressed data */ zcomp_strm_release(comp, zstrm) Decompress: zcomp_decompress(comp, src, src_len, dst); Free compessing backend and its zcomp stream: zcomp_destroy(comp) Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: delete zram_init_device()Sergey Senozhatsky1-11/+5
allocate new `zram_meta' in disksize_store() only for uninitialised zram device, saving a number of allocations and deallocations in case if disksize_store() was called on currently used device. at the same time zram_meta stack variable is not necessary, because we can set ->meta directly. there is also no need in setting QUEUE_FLAG_NONROT queue on every disksize_store(), set it once during device creation. [minchan@kernel.org: handle zram->meta alloc fail case] [minchan@kernel.org: prevent lockdep spew of init_lock] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: move zram size warning to documentationSergey Senozhatsky1-15/+0
Move zram warning about disksize and size of memory correlation to zram documentation. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: drop not used table `count' memberSergey Senozhatsky1-1/+0
struct table `count' member is not used. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: report failed read and write statsSergey Senozhatsky1-0/+4
zram accounted but did not report numbers of failed read and write queries. make these stats available as failed_reads and failed_writes attrs. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: remove zram stats code duplicationSergey Senozhatsky1-59/+23
Introduce ZRAM_ATTR_RO macro that generates device_attribute and default ATTR show() function for existing atomic64_t zram stats. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: use atomic64_t for all zram statsSergey Senozhatsky2-12/+12
This is a preparation patch for stats code duplication removal. 1) use atomic64_t for `pages_zero' and `pages_stored' zram stats. 2) `compr_size' and `pages_zero' struct zram_stats members did not follow the existing device attr naming scheme: zram_stats.ATTR has ATTR_show() function. rename them: -- compr_size -> compr_data_size -- pages_zero -> zero_pages Minchan Kim's note: If we really have trouble with atomic stat operation, we could change it with percpu_counter so that it could solve atomic overhead and unnecessary memory space by introducing unsigned long instead of 64bit atomic_t. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: remove good and bad compress statsSergey Senozhatsky2-13/+0
Remove `good' and `bad' compressed sub-requests stats. RW request may cause a number of RW sub-requests. zram used to account `good' compressed sub-queries (with compressed size less than 50% of original size), `bad' compressed sub-queries (with compressed size greater that 75% of original size), leaving sub-requests with compression size between 50% and 75% of original size not accounted and not reported. zram already accounts each sub-request's compression size so we can calculate real device compression ratio. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: do not pass rw argument to __zram_make_request()Sergey Senozhatsky1-18/+12
Do not pass rw argument down the __zram_make_request() -> zram_bvec_rw() chain, decode it in zram_bvec_rw() instead. Besides, this is the place where we distinguish READ and WRITE bio data directions, so account zram RW stats here, instead of __zram_make_request(). This also allows to account a real number of zram READ/WRITE operations, not just requests (single RW request may cause a number of zram RW ops with separate locking, compression/decompression, etc). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07zram: drop `init_done' struct zram memberSergey Senozhatsky2-11/+11
Introduce init_done() helper function which allows us to drop `init_done' struct zram member. init_done() uses the fact that ->init_done == 1 equals to ->meta != NULL. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07Merge branch 'for-linus' of ↵Linus Torvalds1-28/+59
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph updates from Sage Weil: "The biggest chunk is a series of patches from Ilya that add support for new Ceph osd and crush map features, including some new tunables, primary affinity, and the new encoding that is needed for erasure coding support. This brings things into parity with the server side and the looming firefly release. There is also support for allocation hints in RBD that help limit fragmentation on the server side. There is also a series of patches from Zheng fixing NFS reexport, directory fragmentation support, flock vs fnctl behavior, and some issues with clustered MDS. Finally, there are some miscellaneous fixes from Yunchuan Wen for fscache, Fabian Frederick for ACLs, and from me for fsync(dirfd) behavior" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (79 commits) ceph: skip invalid dentry during dcache readdir libceph: dump pool {read,write}_tier to debugfs libceph: output primary affinity values on osdmap updates ceph: flush cap release queue when trimming session caps ceph: don't grabs open file reference for aborted request ceph: drop extra open file reference in ceph_atomic_open() ceph: preallocate buffer for readdir reply libceph: enable PRIMARY_AFFINITY feature bit libceph: redo ceph_calc_pg_primary() in terms of ceph_calc_pg_acting() libceph: add support for osd primary affinity libceph: add support for primary_temp mappings libceph: return primary from ceph_calc_pg_acting() libceph: switch ceph_calc_pg_acting() to new helpers libceph: introduce apply_temps() helper libceph: introduce pg_to_raw_osds() and raw_to_up_osds() helpers libceph: ceph_can_shift_osds(pool) and pool type defines libceph: ceph_osd_{exists,is_up,is_down}(osd) definitions libceph: enable OSDMAP_ENC feature bit libceph: primary_affinity decode bits libceph: primary_affinity infrastructure ...
2014-04-03rbd: prefix rbd writes with CEPH_OSD_OP_SETALLOCHINT osd opIlya Dryomov1-15/+39
In an effort to reduce fragmentation, prefix every rbd write with a CEPH_OSD_OP_SETALLOCHINT osd op with an expected_write_size value set to the object size (1 << order). Backwards compatibility is taken care of on the libceph/osd side. "The CEPH_OSD_OP_SETALLOCHINT hint is durable, in that it's enough to do it once. The reason every rbd write is prefixed is that rbd doesn't explicitly create objects and relies on writes creating them implicitly, so there is no place to stick a single hint op into. To get around that we decided to prefix every rbd write with a hint (just like write and setattr ops, hint op will create an object implicitly if it doesn't exist)." Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-04-03rbd: num_ops parameter for rbd_osd_req_create()Ilya Dryomov1-10/+18
In preparation for prefixing rbd writes with an allocation hint introduce a num_ops parameter for rbd_osd_req_create(). The rationale is that not every write request is a write op that needs to be prefixed (e.g. watch op), so the num_ops logic needs to be in the callers. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-04-03libceph: bump CEPH_OSD_MAX_OP to 3Ilya Dryomov1-1/+1
Our longest osd request now contains 3 ops: copyup+hint+write. Also, CEPH_OSD_MAX_OP value in a BUG_ON in rbd_osd_req_callback() was hard-coded to 2. Fix it, and switch to rbd_assert while at it. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-04-03rbd: fix error paths in rbd_img_request_fill()Ilya Dryomov1-1/+1
Doing rbd_obj_request_put() in rbd_img_request_fill() error paths is not only insufficient, but also triggers an rbd_assert() in rbd_obj_request_destroy(): Assertion failure in rbd_obj_request_destroy() at line 1867: rbd_assert(obj_request->img_request == NULL); rbd_img_obj_request_add() adds obj_requests to the img_request, the opposite is rbd_img_obj_request_del(). Use it. Fixes: http://tracker.ceph.com/issues/7327 Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-04-03rbd: remove out_partial label in rbd_img_request_fill()Ilya Dryomov1-4/+3
Commit 03507db631c94 ("rbd: fix buffer size for writes to images with snapshots") moved the call to rbd_img_obj_request_add() up, making the out_partial label bogus. Remove it. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-04-02Merge tag 'virtio-next-for-linus' of ↵Linus Torvalds1-3/+17
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio updates from Rusty Russell: "Nothing exciting: virtio-blk users might see a bit of a boost from the doubling of the default queue length though" * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: virtio-blk: base queue-depth on virtqueue ringsize or module param Revert a02bbb1ccfe8: MAINTAINERS: add virtio-dev ML for virtio virtio: fail adding buffer on broken queues. virtio-rng: don't crash if virtqueue is broken. virtio_balloon: don't crash if virtqueue is broken. virtio_blk: don't crash, report error if virtqueue is broken. virtio_net: don't crash if virtqueue is broken. virtio_balloon: don't softlockup on huge balloon changes. virtio: Use pci_enable_msix_exact() instead of pci_enable_msix() MAINTAINERS: virtio-dev is subscribers only tools/virtio: add a missing ) tools/virtio: fix missing kmemleak_ignore symbol tools/virtio: update internal copies of headers
2014-04-01drbd: don't open-code kernel_recvmsg()Al Viro1-11/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01switch nbd to sockfd_lookup/sockfd_putAl Viro1-29/+19
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01Merge branch 'for-3.15/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds24-5486/+5885
Pull block driver update from Jens Axboe: "On top of the core pull request, here's the pull request for the driver related changes for 3.15. It contains: - Improvements for msi-x registration for block drivers (mtip32xx, skd, cciss, nvme) from Alexander Gordeev. - A round of cleanups and improvements for drbd from Andreas Gruenbacher and Rashika Kheria. - A round of clanups and improvements for bcache from Kent. - Removal of sleep_on() and friends in DAC960, ataflop, swim3 from Arnd Bergmann. - Bug fix for a bug in the mtip32xx async completion code from Sam Bradshaw. - Bug fix for accidentally bouncing IO on 32-bit platforms with mtip32xx from Felipe Franciosi" * 'for-3.15/drivers' of git://git.kernel.dk/linux-block: (103 commits) bcache: remove nested function usage bcache: Kill bucket->gc_gen bcache: Kill unused freelist bcache: Rework btree cache reserve handling bcache: Kill btree_io_wq bcache: btree locking rework bcache: Fix a race when freeing btree nodes bcache: Add a real GC_MARK_RECLAIMABLE bcache: Add bch_keylist_init_single() bcache: Improve priority_stats bcache: Better alloc tracepoints bcache: Kill dead cgroup code bcache: stop moving_gc marking buckets that can't be moved. bcache: Fix moving_pred() bcache: Fix moving_gc deadlocking with a foreground write bcache: Fix discard granularity bcache: Fix another bug recovering from unclean shutdown bcache: Fix a bug recovering from unclean shutdown bcache: Fix a journalling reclaim after recovery bug bcache: Fix a null ptr deref in journal replay ...
2014-04-01Merge branch 'for-3.15/core' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+2
Pull core block layer updates from Jens Axboe: "This is the pull request for the core block IO bits for the 3.15 kernel. It's a smaller round this time, it contains: - Various little blk-mq fixes and additions from Christoph and myself. - Cleanup of the IPI usage from the block layer, and associated helper code. From Frederic Weisbecker and Jan Kara. - Duplicate code cleanup in bio-integrity from Gu Zheng. This will give you a merge conflict, but that should be easy to resolve. - blk-mq notify spinlock fix for RT from Mike Galbraith. - A blktrace partial accounting bug fix from Roman Pen. - Missing REQ_SYNC detection fix for blk-mq from Shaohua Li" * 'for-3.15/core' of git://git.kernel.dk/linux-block: (25 commits) blk-mq: add REQ_SYNC early rt,blk,mq: Make blk_mq_cpu_notify_lock a raw spinlock blk-mq: support partial I/O completions blk-mq: merge blk_mq_insert_request and blk_mq_run_request blk-mq: remove blk_mq_alloc_rq blk-mq: don't dump CPU -> hw queue map on driver load blk-mq: fix wrong usage of hctx->state vs hctx->flags blk-mq: allow blk_mq_init_commands() to return failure block: remove old blk_iopoll_enabled variable blktrace: fix accounting of partially completed requests smp: Rename __smp_call_function_single() to smp_call_function_single_async() smp: Remove wait argument from __smp_call_function_single() watchdog: Simplify a little the IPI call smp: Move __smp_call_function_single() below its safe version smp: Consolidate the various smp_call_function_single() declensions smp: Teach __smp_call_function_single() to check for offline cpus smp: Remove unused list_head from csd smp: Iterate functions through llist_for_each_entry_safe() block: Stop abusing rq->csd.list in blk-softirq block: Remove useless IPI struct initialization ...
2014-03-31Merge branch 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds2-20/+40
Pull workqueue changes from Tejun Heo: "PREPARE_[DELAYED_]WORK() were used to change the work function of work items without fully reinitializing it; however, this makes workqueue consider the work item as a different one from before and allows the work item to start executing before the previous instance is finished which can lead to extremely subtle issues which are painful to debug. The interface has never been popular. This pull request contains patches to remove existing usages and kill the interface. As one of the changes was routed during the last devel cycle and another depended on a pending change in nvme, for-3.15 contains a couple merge commits. In addition, interfaces which were deprecated quite a while ago - __cancel_delayed_work() and WQ_NON_REENTRANT - are removed too" * 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: remove deprecated WQ_NON_REENTRANT workqueue: Spelling s/instensive/intensive/ workqueue: remove PREPARE_[DELAYED_]WORK() staging/fwserial: don't use PREPARE_WORK afs: don't use PREPARE_WORK nvme: don't use PREPARE_WORK usb: don't use PREPARE_DELAYED_WORK floppy: don't use PREPARE_[DELAYED_]WORK ps3-vuart: don't use PREPARE_WORK wireless/rt2x00: don't use PREPARE_WORK in rt2800usb.c workqueue: Remove deprecated __cancel_delayed_work()
2014-03-29Merge branch 'for-linus' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph fix from Sage Weil: "This drops a bad assert that a few users have been hitting but we've only recently been able to track down" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: rbd: drop an unsafe assertion