1. Oct 04, 2014
    • Joern Engel's avatar
      qla_target: don't delete changed nacls · f4c24db1
      Joern Engel authored
      
      
      The code is currently riddled with "drop the hardware_lock to avoid a
      deadlock" bugs that expose races.  One of those races seems to expose a
      valid warning in tcm_qla2xxx_clear_nacl_from_fcport_map.  Add some
      bandaid to it.
      
      Signed-off-by: default avatarJoern Engel <joern@logfs.org>
      Cc: <stable@vger.kernel.org> # v3.5+
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      f4c24db1
    • Andy Grover's avatar
      target/user: Recalculate pad size inside is_ring_space_avail() · f56574a2
      Andy Grover authored
      
      
      If more than one thread is waiting for command ring space that includes
      a PAD, then if the first one finishes (inserts a PAD and a CMD at the
      start of the cmd ring) then the second one will incorrectly think it still
      needs to insert a PAD (i.e. cmdr_space_needed is now wrong.) This will
      lead to it asking for more space than it actually needs, and then inserting
      a PAD somewhere else than at the end -- not what we want.
      
      This patch moves the pad calculation inside is_ring_space_available() so
      in the above scenario the second thread would then ask for space not
      including a PAD. The patch also inserts a PAD op based upon an up-to-date
      cmd_head, instead of the potentially stale value.
      
      Signed-off-by: default avatarAndy Grover <agrover@redhat.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      f56574a2
    • Hannes Reinecke's avatar
      tcm_loop: Fixup tag handling · 6375f890
      Hannes Reinecke authored
      
      
      The SCSI command tag is set to the tag assigned from the block
      layer, not the SCSI-II tag message. So we need to convert
      it into the correct SCSI-II tag message based on the
      device flags, not the tag value itself.
      
      Signed-off-by: default avatarHannes Reinecke <hare@suse.de>
      Reviewed-by: default avatarSagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      6375f890
    • Sagi Grimberg's avatar
      iser-target: Fix smatch warning · 1acff63f
      Sagi Grimberg authored
      
      
      Unused return value from down_interruptible
      
      Reported-by: default avatarOr Gerlitz <ogerlitz@mellanox.com>
      Signed-off-by: default avatarSagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      1acff63f
    • Nicholas Bellinger's avatar
      target/user: Fix up smatch warnings in tcmu_netlink_event · 6e14eab9
      Nicholas Bellinger authored
      
      
      This patch fixes up the following unused return smatch warnings:
      
        drivers/target/target_core_user.c:778 tcmu_netlink_event warn: unused return: ret = nla_put_string()
        drivers/target/target_core_user.c:780 tcmu_netlink_event warn: unused `return: ret = nla_put_u32()
      
      (Fix up missing semicolon: grover)
      
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      6e14eab9
    • Andy Grover's avatar
      target: Add a user-passthrough backstore · 7c9e7a6f
      Andy Grover authored
      
      
      Add a LIO storage engine that presents commands to userspace for execution.
      This would allow more complex backstores to be implemented out-of-kernel,
      and also make experimentation a-la FUSE (but at the SCSI level -- "SUSE"?)
      possible.
      
      It uses a mmap()able UIO device per LUN to share a command ring and data
      area. The commands are raw SCSI CDBs and iovs for in/out data. The command
      ring is also reused for returning scsi command status and optional sense
      data.
      
      This implementation is based on Shaohua Li's earlier version but heavily
      modified. Differences include:
      
      * Shared memory allocated by kernel, not locked-down user pages
      * Single ring for command request and response
      * Offsets instead of embedded pointers
      * Generic SCSI CDB passthrough instead of per-cmd specialization in ring
        format.
      * Uses UIO device instead of anon_file passed in mailbox.
      * Optional in-kernel handling of some commands.
      
      The main reason for these differences is to permit greater resiliency
      if the user process dies or hangs.
      
      Things not yet implemented (on purpose):
      
      * Zero copy. The data area is flexible enough to allow page flipping or
        backend-allocated pages to be used by fabrics, but it's not clear these
        are performance wins. Can come later.
      * Out-of-order command completion by userspace. Possible to add by just
        allowing userspace to change cmd_id in rsp cmd entries, but currently
        not supported.
      * No locks between kernel cmd submission and completion routines. Sounds
        like it's possible, but this can come later.
      * Sparse allocation of mmaped area. Current code vmallocs the whole thing.
        If the mapped area was larger and not fully mapped then the driver would
        have more freedom to change cmd and data area sizes based on demand.
      
      Current code open issues:
      
      * The use of idrs may be overkill -- we maybe can replace them with a
        simple counter to generate cmd_ids, and a hash table to get a cmd_id's
        associated pointer.
      * Use of a free-running counter for cmd ring instead of explicit modulo
        math. This would require power-of-2 cmd ring size.
      
      (Add kconfig depends NET - Randy)
      
      Signed-off-by: default avatarAndy Grover <agrover@redhat.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      7c9e7a6f
  2. Oct 03, 2014
  3. Oct 02, 2014
  4. Sep 18, 2014
  5. Sep 16, 2014
  6. Sep 15, 2014
    • Linus Torvalds's avatar
      Linux 3.17-rc5 · 9e82bf01
      Linus Torvalds authored
      9e82bf01
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · 83373f70
      Linus Torvalds authored
      Pull vfs fixes from Al Viro:
       "double iput() on failure exit in lustre, racy removal of spliced
        dentries from ->s_anon in __d_materialise_dentry() plus a bunch of
        assorted RCU pathwalk fixes"
      
      The RCU pathwalk fixes end up fixing a couple of cases where we
      incorrectly dropped out of RCU walking, due to incorrect initialization
      and testing of the sequence locks in some corner cases.  Since dropping
      out of RCU walk mode forces the slow locked accesses, those corner cases
      slowed down quite dramatically.
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
        be careful with nd->inode in path_init() and follow_dotdot_rcu()
        don't bugger nd->seq on set_root_rcu() from follow_dotdot_rcu()
        fix bogus read_seqretry() checks introduced in b37199e6
        move the call of __d_drop(anon) into __d_materialise_unique(dentry, anon)
        [fix] lustre: d_make_root() does iput() on dentry allocation failure
      83373f70
    • Linus Torvalds's avatar
      vfs: avoid non-forwarding large load after small store in path lookup · 9226b5b4
      Linus Torvalds authored
      The performance regression that Josef Bacik reported in the pathname
      lookup (see commit 99d263d4
      
       "vfs: fix bad hashing of dentries") made
      me look at performance stability of the dcache code, just to verify that
      the problem was actually fixed.  That turned up a few other problems in
      this area.
      
      There are a few cases where we exit RCU lookup mode and go to the slow
      serializing case when we shouldn't, Al has fixed those and they'll come
      in with the next VFS pull.
      
      But my performance verification also shows that link_path_walk() turns
      out to have a very unfortunate 32-bit store of the length and hash of
      the name we look up, followed by a 64-bit read of the combined hash_len
      field.  That screws up the processor store to load forwarding, causing
      an unnecessary hickup in this critical routine.
      
      It's caused by the ugly calling convention for the "hash_name()"
      function, and easily fixed by just making hash_name() fill in the whole
      'struct qstr' rather than passing it a pointer to just the hash value.
      
      With that, the profile for this function looks much smoother.
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9226b5b4
    • Linus Torvalds's avatar
      Merge branch 'parisc-3.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux · 5910cfdc
      Linus Torvalds authored
      Pull parisc updates from Helge Deller:
       "The most important patch is a new Light Weigth Syscall (LWS) for 8,
        16, 32 and 64 bit atomic CAS operations which is required in order to
        be able to implement the atomic gcc builtins on our platform.
      
        Other than that, we wire up the seccomp, getrandom and memfd_create
        syscalls, fixes a minor off-by-one bug and a wrong printk string"
      
      * 'parisc-3.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
        parisc: Implement new LWS CAS supporting 64 bit operations.
        parisc: Wire up seccomp, getrandom and memfd_create syscalls
        parisc: dino: fix %d confusingly prefixed with 0x in format string
        parisc: sys_hpux: NUL terminator is one past the end
      5910cfdc