1. 30 May, 2018 1 commit
  2. 03 Feb, 2018 1 commit
    • David Disseldorp's avatar
      null_blk: fix dev->badblocks leak · 2e194c9c
      David Disseldorp authored
      
      [ Upstream commit 1addb798 ]
      
      null_alloc_dev() allocates memory for dev->badblocks, but cleanup
      currently only occurs in the configfs release codepath, missing a number
      of other places.
      
      This bug was found running the blktests block/010 test, alongside
      kmemleak:
      rapido1:/blktests# ./check block/010
      ...
      rapido1:/blktests# echo scan > /sys/kernel/debug/kmemleak
      [  306.966708] kmemleak: 32 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
      rapido1:/blktests# cat /sys/kernel/debug/kmemleak
      unreferenced object 0xffff88001f86d000 (size 4096):
        comm "modprobe", pid 231, jiffies 4294892415 (age 318.252s)
        hex dump (first 32 bytes):
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
        backtrace:
          [<ffffffff814b0379>] kmemleak_alloc+0x49/0xa0
          [<ffffffff810f180f>] kmem_cache_alloc+0x9f/0xe0
          [<ffffffff8124e45f>] badblocks_init+0x2f/0x60
          [<ffffffffa0019fae>] 0xffffffffa0019fae
          [<ffffffffa0021273>] nullb_device_badblocks_store+0x63/0x130 [null_blk]
          [<ffffffff810004cd>] do_one_initcall+0x3d/0x170
          [<ffffffff8109fe0d>] do_init_module+0x56/0x1e9
          [<ffffffff8109ebd7>] load_module+0x1c47/0x26a0
          [<ffffffff8109f819>] SyS_finit_module+0xa9/0xd0
          [<ffffffff814b4f60>] entry_SYSCALL_64_fastpath+0x13/0x94
      
      Fixes: 2f54a613 ("nullb: badbblocks support")
      Reviewed-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarDavid Disseldorp <ddiss@suse.de>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      Signed-off-by: default avatarSasha Levin <alexander.levin@verizon.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      2e194c9c
  3. 20 Dec, 2017 1 commit
  4. 29 Aug, 2017 1 commit
    • Ying Huang's avatar
      smp: Avoid using two cache lines for struct call_single_data · 966a9671
      Ying Huang authored
      struct call_single_data is used in IPIs to transfer information between
      CPUs.  Its size is bigger than sizeof(unsigned long) and less than
      cache line size.  Currently it is not allocated with any explicit alignment
      requirements.  This makes it possible for allocated call_single_data to
      cross two cache lines, which results in double the number of the cache lines
      that need to be transferred among CPUs.
      
      This can be fixed by requiring call_single_data to be aligned with the
      size of call_single_data. Currently the size of call_single_data is the
      power of 2.  If we add new fields to call_single_data, we may need to
      add padding to make sure the size of new definition is the power of 2
      as well.
      
      Fortunately, this is enforced by GCC, which will report bad sizes.
      
      To set alignment requirements of call_single_data to the size of
      call_single_data, a struct definition and a typedef is used.
      
      To test the effect of the patch, I used the vm-scalability multiple
      thread swap test case (swap-w-seq-mt).  The test will create multiple
      threads and each thread will eat memory until all RAM and part of swap
      is used, so that huge number of IPIs are triggered when unmapping
      memory.  In the test, the throughput of memory writing improves ~5%
      compared with misaligned call_single_data, because of faster IPIs.
      Suggested-by: default avatarPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: default avatarHuang, Ying <ying.huang@intel.com>
      [ Add call_single_data_t and align with size of call_single_data. ]
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Aaron Lu <aaron.lu@intel.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      966a9671
  5. 28 Aug, 2017 2 commits
  6. 25 Aug, 2017 2 commits
  7. 23 Aug, 2017 9 commits
    • Shaohua Li's avatar
      nullb: badbblocks support · 2f54a613
      Shaohua Li authored
      Sometime disk could have tracks broken and data there is inaccessable,
      but data in other parts can be accessed in normal way. MD RAID supports
      such disks. But we don't have a good way to test it, because we can't
      control which part of a physical disk is bad. For a virtual disk, this
      can be easily controlled.
      
      This patch adds a new 'badblock' attribute. Configure it in this way:
      echo "+1-100" > xxx/badblock, this will make sector [1-100] as bad
      blocks.
      echo "-20-30" > xxx/badblock, this will make sector [20-30] good
      
      If badblocks are accessed, the nullb disk will return IO error. Other
      parts of the disk can accessed in normal way.
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      2f54a613
    • Shaohua Li's avatar
      nullb: emulate cache · deb78b41
      Shaohua Li authored
      Software must flush disk cache to guarantee data safety. To check if
      software correctly does disk cache flush, we must know the behavior of
      disk. But physical disk behavior is uncontrollable. Even software
      doesn't do the flush, the disk probably does the flush. This patch tries
      to emulate a cache in the test disk.
      
      All write will go to a cache first, when the cache is full, we then
      flush some data to disk storage. A flush request will flush all data of
      the cache to disk storage. A FUA write will write to memory store
      directly and revalidate data in cache. If there is a power failure (by
      writing to power attribute, 'echo 0 > disk_name/power'), we discard all
      data in the cache, but preserve the data in disk storage. Later we can
      power on the disk again as usual (write 1 to 'power' attribute), then we
      can check data integrity and very if software does everything correctly.
      
      A new attribute 'cache_size' (in MB) is added to configure cache size.
      
      Based on original patch from Kyungchan Koh
      Signed-off-by: default avatarKyungchan Koh <kkc6196@fb.com>
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      deb78b41
    • Shaohua Li's avatar
      nullb: bandwidth control · eff2c4f1
      Shaohua Li authored
      In test, we usually expect controllable disk speed. For example, in a
      raid array, we'd like some disks are fast and some are slow. MD RAID
      actually has a feature for this. To test the feature, we'd like to make
      the disk run in specific speed.
      
      block throttling probably can be used for this purpose, but it requires
      cgroup setup. Here we just implement a simple throttling mechanism in
      the driver. There is slight fluctuation in the mechanism, but it's good
      enough for test.
      
      To configure the bandwidth cap, user sets the 'mbps' attribute. mbps is
      MB/s.
      
      Based on original patch from Kyungchan Koh
      Signed-off-by: default avatarKyungchan Koh <kkc6196@fb.com>
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      eff2c4f1
    • Shaohua Li's avatar
      nullb: support discard · 306eb6b4
      Shaohua Li authored
      discard makes sense for memory backed disk. And also it's useful to test
      if upper layer supports dicard correctly.
      
      User configures 'discard' attribute to enable/disable dicard support.
      
      Based on original patch from Kyungchan Koh
      Signed-off-by: default avatarKyungchan Koh <kkc6196@fb.com>
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      306eb6b4
    • Shaohua Li's avatar
      nullb: support memory backed store · 5bcd0e0c
      Shaohua Li authored
      This adds memory backed store in nullb.
      
      User configure 'memory_backed' attribute for this. By default, nullb
      disk doesn't use memory backed store.
      
      Based on original patch from Kyungchan Koh
      Signed-off-by: default avatarKyungchan Koh <kkc6196@fb.com>
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      5bcd0e0c
    • Shaohua Li's avatar
      nullb: use ida to manage index · 94bc02e3
      Shaohua Li authored
      We now dynamically create disks. Managing the disk index with ida to
      avoid bump up the index too much.
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      94bc02e3
    • Shaohua Li's avatar
      nullb: add interface to power on disk · cedcafad
      Shaohua Li authored
      The device created in nullb configfs interface isn't power on by
      default. After user configures the device, user can do 'echo 1 >
      xxx/nullb/device_name/power' to power on the device, which will create a
      disk. the xxx/nullb/device_name/index is the disk index, so if the index
      is 2, the new created disk should be named as /dev/nullb2. Note, the
      'index' is only valid after disk is power on.
      
      'echo 0 > xxx/nullb/device_name/power' will remove the disk. Note, this
      doesn't remove the device. To remove the device, user should do 'rmdir
      xxx/nullb/device_name'. Removing the device will remove the disk too.
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      cedcafad
    • Shaohua Li's avatar
      nullb: add configfs interface · 3bf2bd20
      Shaohua Li authored
      Add configfs interface for nullb. configfs interface is more flexible
      and easy to configure in a per-disk basis.
      
      Configuration is something like this:
      mount -t configfs none /mnt
      
      Checking which features the driver supports:
      cat /mnt/nullb/features
      
      The 'features' attribute is for future extension. We probably will add
      new features into the driver, userspace can check this attribute to find
      the supported features.
      
      Create/remove a device:
      mkdir/rmdir /mnt/nullb/a
      
      Then configure the device by setting attributes under /mnt/nullb/a, most
      of nullb supported module parameters are converted to attributes:
      size; /* device size in MB */
      completion_nsec; /* time in ns to complete a request */
      submit_queues; /* number of submission queues */
      home_node; /* home node for the device */
      queue_mode; /* block interface */
      blocksize; /* block size */
      irqmode; /* IRQ completion handler */
      hw_queue_depth; /* queue depth */
      use_lightnvm; /* register as a LightNVM device */
      blocking; /* blocking blk-mq device */
      use_per_node_hctx; /* use per-node allocation for hardware context */
      
      Note, creating a device doesn't create a disk immediately. Creating a
      disk is done in two phases: create a device and then power on the
      device. Next patch will introduce device power on.
      
      Based on original patch from Kyungchan Koh
      Signed-off-by: default avatarKyungchan Koh <kkc6196@fb.com>
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      3bf2bd20
    • Shaohua Li's avatar
      nullb: factor disk parameters · 2984c868
      Shaohua Li authored
      When we switch to configfs interface, each disk could have different
      configuration. To prepare for the change, we move most disk setting to a
      separate data structure. The existing module parameter interface is
      kept. The 'nr_devices' and 'shared_tags' don't make sense for per-disk
      setting, so they are remained as global settings.
      Signed-off-by: default avatarShaohua Li <shli@fb.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      2984c868
  8. 07 Aug, 2017 2 commits
  9. 06 Jul, 2017 1 commit
  10. 20 Jun, 2017 1 commit
    • Jens Axboe's avatar
      null_blk: add support for shared tags · 82f402fe
      Jens Axboe authored
      Some storage drivers need to share tag sets between devices. It's
      useful to be able to model that with null_blk, to find hangs or
      performance issues.
      
      Add a 'shared_tags' bool module parameter that. If that is set to
      true and nr_devices is bigger than 1, all devices allocated will
      share the same tag set.
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      82f402fe
  11. 09 Jun, 2017 2 commits
    • Christoph Hellwig's avatar
      blk-mq: switch ->queue_rq return value to blk_status_t · fc17b653
      Christoph Hellwig authored
      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: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      fc17b653
    • Christoph Hellwig's avatar
      block: introduce new block status code type · 2a842aca
      Christoph Hellwig authored
      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: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      2a842aca
  12. 20 Apr, 2017 2 commits
  13. 19 Apr, 2017 1 commit
  14. 31 Mar, 2017 1 commit
  15. 30 Mar, 2017 1 commit
    • Jens Axboe's avatar
      null_blk: add blocking mode · db5bcf87
      Jens Axboe authored
      This adds a new module parameter to null_blk, blocking. If set, null_blk
      will set the BLK_MQ_F_BLOCKING flag, indicating that it sometimes/always
      needs to block in its ->queue_rq() function.  The intent is to help find
      regressions in blocking drivers, since not many of them exist.
      
      If null_blk is loaded with submit_queues > 1 and blocking=1, this
      shows the regression recently fixed by bf4907c0.
      Reviewed-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      db5bcf87
  16. 31 Jan, 2017 3 commits
  17. 25 Dec, 2016 1 commit
    • Thomas Gleixner's avatar
      ktime: Cleanup ktime_set() usage · 8b0e1953
      Thomas Gleixner authored
      ktime_set(S,N) was required for the timespec storage type and is still
      useful for situations where a Seconds and Nanoseconds part of a time value
      needs to be converted. For anything where the Seconds argument is 0, this
      is pointless and can be replaced with a simple assignment.
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      8b0e1953
  18. 16 Nov, 2016 1 commit
  19. 21 Sep, 2016 2 commits
    • Matias Bjørling's avatar
      lightnvm: control life of nvm_dev in driver · b0b4e09c
      Matias Bjørling authored
      LightNVM compatible device drivers does not have a method to expose
      LightNVM specific sysfs entries.
      
      To enable LightNVM sysfs entries to be exposed, lightnvm device
      drivers require a struct device to attach it to. To allow both the
      actual device driver and lightnvm sysfs entries to coexist, the device
      driver tracks the lifetime of the nvm_dev structure.
      
      This patch refactors NVMe and null_blk to handle the lifetime of struct
      nvm_dev, which eliminates the need for struct gendisk when a lightnvm
      compatible device is provided.
      Signed-off-by: default avatarMatias Bjørling <m@bjorling.me>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      b0b4e09c
    • Matias Bjørling's avatar
      null_blk: refactor to support non-gendisk devices · 9ae2d0aa
      Matias Bjørling authored
      With LightNVM enabled devices, the gendisk structure is not exposed
      to the user. This hides the device driver specific sysfs entries, and
      prevents binding of LightNVM geometry information to the device.
      
      Refactor the device registration process, so that gendisk and
      non-gendisk devices are easily managed.
      Signed-off-by: default avatarMatias Bjørling <m@bjorling.me>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      9ae2d0aa
  20. 15 Sep, 2016 1 commit
  21. 20 Jul, 2016 1 commit
  22. 19 Mar, 2016 1 commit
  23. 11 Feb, 2016 1 commit
    • Matias Bjørling's avatar
      null_blk: oops when initializing without lightnvm · a514379b
      Matias Bjørling authored
      If the LightNVM subsystem is not compiled into the kernel, and the
      null_blk device driver requests lightnvm to be initialized. The call to
      nvm_register fails and the null_add_dev function cleans up the
      initialization. However, at this point the null block device has
      already been added to the nullb_list and thus a second cleanup will
      occur when the function has returned, that leads to a double call to
      blk_cleanup_queue.
      Signed-off-by: default avatarMatias Bjørling <m@bjorling.me>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      a514379b
  24. 04 Feb, 2016 1 commit
    • Matias Bjørling's avatar
      lightnvm: allow to force mm initialization · bf643185
      Matias Bjørling authored
      System block allows the device to initialize with its configured media
      manager. The system blocks is written to disk, and read again when media
      manager is determined. For this to work, the backend must store the
      data. Device drivers, such as null_blk, does not have any backend
      storage. This patch allows the media manager to be initialized without a
      storage backend.
      
      It also fix incorrect configuration of capabilities in null_blk, as it
      does not support get/set bad block interface.
      Signed-off-by: default avatarMatias Bjørling <m@bjorling.me>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      bf643185