1. 06 3月, 2013 10 次提交
  2. 03 3月, 2013 7 次提交
    • J
      mm: define VM_GROWSUP for CONFIG_METAG · 9ca52ed9
      James Hogan 提交于
      Commit cc2383ec ("mm: introduce
      arch-specific vma flag VM_ARCH_1") merged in v3.7-rc1.
      
      The above commit combined several arch-specific vma flags into one, and
      in the process it changed the VM_GROWSUP definition to depend on
      specific architectures rather than CONFIG_STACK_GROWSUP. Therefore add
      an ifdef for CONFIG_METAG to also set VM_GROWSUP.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Michel Lespinasse <walken@google.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: linux-mm@kvack.org
      9ca52ed9
    • J
      metag: Internal and external irqchips · 5698c50d
      James Hogan 提交于
      Meta core internal interrupts (from HWSTATMETA and friends) are vectored
      onto the TR1 core trigger for the current thread. This is demultiplexed
      in irq-metag.c to individual Linux IRQs for each internal interrupt.
      
      External SoC interrupts (from HWSTATEXT and friends) are vectored onto
      the TR2 core trigger for the current thread. This is demultiplexed in
      irq-metag-ext.c to individual Linux IRQs for each external SoC interrupt.
      The external irqchip has devicetree bindings for configuring the number
      of irq banks and the type of masking available.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Grant Likely <grant.likely@secretlab.ca>
      Cc: Rob Herring <rob.herring@calxeda.com>
      Cc: Rob Landley <rob@landley.net>
      Cc: Dom Cobley <popcornmix@gmail.com>
      Cc: Simon Arlott <simon@fire.lp0.eu>
      Cc: Viresh Kumar <viresh.kumar@linaro.org>
      Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
      Cc: devicetree-discuss@lists.ozlabs.org
      Cc: linux-doc@vger.kernel.org
      5698c50d
    • J
      metag: Time keeping · a2c5d4ed
      James Hogan 提交于
      Add time keeping code for metag. Meta hardware threads have 2 timers.
      The background timer (TXTIMER) is used as a free-running time base, and
      the interrupt timer (TXTIMERI) is used for the timer interrupt. Both
      counters traditionally count at approximately 1MHz.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: John Stultz <johnstul@us.ibm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      a2c5d4ed
    • J
      metag: ptrace · bc3966bf
      James Hogan 提交于
      The ptrace interface for metag provides access to some core register
      sets using the PTRACE_GETREGSET and PTRACE_SETREGSET operations. The
      details of the internal context structures is abstracted into user API
      structures to both ease use and allow flexibility to change the internal
      context layouts. Copyin and copyout functions for these register sets
      are exposed to allow signal handling code to use them to copy to and
      from the signal context.
      
      struct user_gp_regs (NT_PRSTATUS) provides access to the core general
      purpose register context.
      
      struct user_cb_regs (NT_METAG_CBUF) provides access to the TXCATCH*
      registers which contains information abuot a memory fault, unaligned
      access error or watchpoint. This can be modified to alter the way the
      fault is replayed on resume ("catch replay"), or to prevent the replay
      taking place.
      
      struct user_rp_state (NT_METAG_RPIPE) provides access to the state of
      the Meta read pipeline which can be used to hide memory latencies in
      hand optimised data loops.
      
      Extended DSP register state, DSP RAM, and hardware breakpoint registers
      aren't yet exposed through ptrace.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Denys Vlasenko <vda.linux@googlemail.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Tony Lindgren <tony@atomide.com>
      Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
      bc3966bf
    • J
      asm-generic/unistd.h: handle symbol prefixes in cond_syscall · 4dd3c959
      James Hogan 提交于
      Some architectures have symbol prefixes and set CONFIG_SYMBOL_PREFIX,
      but this wasn't taken into account by the generic cond_syscall. It's
      easy enough to fix in a generic fashion, so add the symbol prefix to
      symbol names in cond_syscall when CONFIG_SYMBOL_PREFIX is set.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Acked-by: NArnd Bergmann <arnd@arndb.de>
      Acked-by: NMike Frysinger <vapier@gentoo.org>
      4dd3c959
    • J
      asm-generic/io.h: check CONFIG_VIRT_TO_BUS · c93d0312
      James Hogan 提交于
      Make asm-generic/io.h check CONFIG_VIRT_TO_BUS before defining
      virt_to_bus() and bus_to_virt(), otherwise it's easy to accidentally
      have a silently failing incorrect direct mapped definition rather then
      no definition at all.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Acked-by: NArnd Bergmann <arnd@arndb.de>
      c93d0312
    • Y
      x86, ACPI, mm: Revert movablemem_map support · 20e6926d
      Yinghai Lu 提交于
      Tim found:
      
        WARNING: at arch/x86/kernel/smpboot.c:324 topology_sane.isra.2+0x6f/0x80()
        Hardware name: S2600CP
        sched: CPU #1's llc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency.
        smpboot: Booting Node   1, Processors  #1
        Modules linked in:
        Pid: 0, comm: swapper/1 Not tainted 3.9.0-0-generic #1
        Call Trace:
          set_cpu_sibling_map+0x279/0x449
          start_secondary+0x11d/0x1e5
      
      Don Morris reproduced on a HP z620 workstation, and bisected it to
      commit e8d19552 ("acpi, memory-hotplug: parse SRAT before memblock
      is ready")
      
      It turns out movable_map has some problems, and it breaks several things
      
      1. numa_init is called several times, NOT just for srat. so those
      	nodes_clear(numa_nodes_parsed)
      	memset(&numa_meminfo, 0, sizeof(numa_meminfo))
         can not be just removed.  Need to consider sequence is: numaq, srat, amd, dummy.
         and make fall back path working.
      
      2. simply split acpi_numa_init to early_parse_srat.
         a. that early_parse_srat is NOT called for ia64, so you break ia64.
         b.  for (i = 0; i < MAX_LOCAL_APIC; i++)
      	     set_apicid_to_node(i, NUMA_NO_NODE)
           still left in numa_init. So it will just clear result from early_parse_srat.
           it should be moved before that....
         c.  it breaks ACPI_TABLE_OVERIDE...as the acpi table scan is moved
             early before override from INITRD is settled.
      
      3. that patch TITLE is total misleading, there is NO x86 in the title,
         but it changes critical x86 code. It caused x86 guys did not
         pay attention to find the problem early. Those patches really should
         be routed via tip/x86/mm.
      
      4. after that commit, following range can not use movable ram:
        a. real_mode code.... well..funny, legacy Node0 [0,1M) could be hot-removed?
        b. initrd... it will be freed after booting, so it could be on movable...
        c. crashkernel for kdump...: looks like we can not put kdump kernel above 4G
      	anymore.
        d. init_mem_mapping: can not put page table high anymore.
        e. initmem_init: vmemmap can not be high local node anymore. That is
           not good.
      
      If node is hotplugable, the mem related range like page table and
      vmemmap could be on the that node without problem and should be on that
      node.
      
      We have workaround patch that could fix some problems, but some can not
      be fixed.
      
      So just remove that offending commit and related ones including:
      
       f7210e6c ("mm/memblock.c: use CONFIG_HAVE_MEMBLOCK_NODE_MAP to
          protect movablecore_map in memblock_overlaps_region().")
      
       01a178a9 ("acpi, memory-hotplug: support getting hotplug info from
          SRAT")
      
       27168d38 ("acpi, memory-hotplug: extend movablemem_map ranges to
          the end of node")
      
       e8d19552 ("acpi, memory-hotplug: parse SRAT before memblock is
          ready")
      
       fb06bc8e ("page_alloc: bootmem limit with movablecore_map")
      
       42f47e27 ("page_alloc: make movablemem_map have higher priority")
      
       6981ec31 ("page_alloc: introduce zone_movable_limit[] to keep
          movable limit for nodes")
      
       34b71f1e ("page_alloc: add movable_memmap kernel parameter")
      
       4d59a751 ("x86: get pg_data_t's memory from other node")
      
      Later we should have patches that will make sure kernel put page table
      and vmemmap on local node ram instead of push them down to node0.  Also
      need to find way to put other kernel used ram to local node ram.
      Reported-by: NTim Gardner <tim.gardner@canonical.com>
      Reported-by: NDon Morris <don.morris@hp.com>
      Bisected-by: NDon Morris <don.morris@hp.com>
      Tested-by: NDon Morris <don.morris@hp.com>
      Signed-off-by: NYinghai Lu <yinghai@kernel.org>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Thomas Renninger <trenn@suse.de>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Tang Chen <tangchen@cn.fujitsu.com>
      Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      20e6926d
  3. 02 3月, 2013 9 次提交
    • A
      constify path_get/path_put and fs_struct.c stuff · dcf787f3
      Al Viro 提交于
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      dcf787f3
    • A
      cache the value of file_inode() in struct file · dd37978c
      Al Viro 提交于
      Note that this thing does *not* contribute to inode refcount;
      it's pinned down by dentry.
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      dd37978c
    • A
      dm: add target num_write_bios fn · b0d8ed4d
      Alasdair G Kergon 提交于
      Add a num_write_bios function to struct target.
      
      If an instance of a target sets this, it will be queried before the
      target's mapping function is called on a write bio, and the response
      controls the number of copies of the write bio that the target will
      receive.
      
      This provides a convenient way for a target to send the same data to
      more than one device.  The new cache target uses this in writethrough
      mode, to send the data both to the cache and the backing device.
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      b0d8ed4d
    • M
      dm kcopyd: introduce configurable throttling · df5d2e90
      Mikulas Patocka 提交于
      This patch allows the administrator to reduce the rate at which kcopyd
      issues I/O.
      
      Each module that uses kcopyd acquires a throttle parameter that can be
      set in /sys/module/*/parameters.
      
      We maintain a history of kcopyd usage by each module in the variables
      io_period and total_period in struct dm_kcopyd_throttle. The actual
      kcopyd activity is calculated as a percentage of time equal to
      "(100 * io_period / total_period)".  This is compared with the user-defined
      throttle percentage threshold and if it is exceeded, we sleep.
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      df5d2e90
    • M
      dm ioctl: allow message to return data · a2606241
      Mikulas Patocka 提交于
      This patch introduces enhanced message support that allows the
      device-mapper core to recognise messages that are common to all devices,
      and for messages to return data to userspace.
      
      Core messages are processed by the function "message_for_md".  If the
      device mapper doesn't support the message, it is passed to the target
      driver.
      
      If the message returns data, the kernel sets the flag
      DM_MESSAGE_OUT_FLAG.
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      a2606241
    • M
      dm ioctl: optimize functions without variable params · 02cde50b
      Mikulas Patocka 提交于
      Device-mapper ioctls receive and send data in a buffer supplied
      by userspace.  The buffer has two parts.  The first part contains
      a 'struct dm_ioctl' and has a fixed size.  The second part depends
      on the ioctl and has a variable size.
      
      This patch recognises the specific ioctls that do not use the variable
      part of the buffer and skips allocating memory for it.
      
      In particular, when a device is suspended and a resume ioctl is sent,
      this now avoid memory allocation completely.
      
      The variable "struct dm_ioctl tmp" is moved from the function
      copy_params to its caller ctl_ioctl and renamed to param_kernel.
      It is used directly when the ioctl function doesn't need any arguments.
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      02cde50b
    • A
      dm: rename request variables to bios · 55a62eef
      Alasdair G Kergon 提交于
      Use 'bio' in the name of variables and functions that deal with
      bios rather than 'request' to avoid confusion with the normal
      block layer use of 'request'.
      
      No functional changes.
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      55a62eef
    • M
      dm: fix truncated status strings · fd7c092e
      Mikulas Patocka 提交于
      Avoid returning a truncated table or status string instead of setting
      the DM_BUFFER_FULL_FLAG when the last target of a table fills the
      buffer.
      
      When processing a table or status request, the function retrieve_status
      calls ti->type->status. If ti->type->status returns non-zero,
      retrieve_status assumes that the buffer overflowed and sets
      DM_BUFFER_FULL_FLAG.
      
      However, targets don't return non-zero values from their status method
      on overflow. Most targets returns always zero.
      
      If a buffer overflow happens in a target that is not the last in the
      table, it gets noticed during the next iteration of the loop in
      retrieve_status; but if a buffer overflow happens in the last target, it
      goes unnoticed and erroneously truncated data is returned.
      
      In the current code, the targets behave in the following way:
      * dm-crypt returns -ENOMEM if there is not enough space to store the
        key, but it returns 0 on all other overflows.
      * dm-thin returns errors from the status method if a disk error happened.
        This is incorrect because retrieve_status doesn't check the error
        code, it assumes that all non-zero values mean buffer overflow.
      * all the other targets always return 0.
      
      This patch changes the ti->type->status function to return void (because
      most targets don't use the return code). Overflow is detected in
      retrieve_status: if the status method fills up the remaining space
      completely, it is assumed that buffer overflow happened.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      fd7c092e
    • R
      hsi: fix kernel-doc warnings · 8eae508b
      Randy Dunlap 提交于
      Fix kernel-doc warnings in hsi files:
      
        Warning(include/linux/hsi/hsi.h:136): Excess struct/union/enum/typedef member 'e_handler' description in 'hsi_client'
        Warning(include/linux/hsi/hsi.h:136): Excess struct/union/enum/typedef member 'pclaimed' description in 'hsi_client'
        Warning(include/linux/hsi/hsi.h:136): Excess struct/union/enum/typedef member 'nb' description in 'hsi_client'
        Warning(drivers/hsi/hsi.c:434): No description found for parameter 'handler'
        Warning(drivers/hsi/hsi.c:434): Excess function parameter 'cb' description in 'hsi_register_port_event'
      
      Don't document "private:" fields with kernel-doc notation.
      If you want to leave them fully documented, that's OK, but
      then don't mark them as "private:".
      Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
      Cc: Carlos Chinea <carlos.chinea@nokia.com>
      Cc: Linus Walleij <linus.walleij@linaro.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: linux-kernel@vger.kernel.org
      Cc: linux-omap@vger.kernel.org
      Acked-by: NNishanth Menon <nm@ti.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8eae508b
  4. 01 3月, 2013 6 次提交
  5. 28 2月, 2013 8 次提交
    • A
      dmaengine: dw_dmac: move to generic DMA binding · f9c6a655
      Arnd Bergmann 提交于
      The original device tree binding for this driver, from Viresh Kumar
      unfortunately conflicted with the generic DMA binding, and did not allow
      to completely seperate slave device configuration from the controller.
      
      This is an attempt to replace it with an implementation of the generic
      binding, but it is currently completely untested, because I do not have
      any hardware with this particular controller.
      
      The patch applies on top of the slave-dma tree, which contains both the base
      support for the generic DMA binding, as well as the earlier attempt from
      Viresh. Both of these are currently not merged upstream however.
      
      This version incorporates feedback from Viresh Kumar, Andy Shevchenko
      and Russell King.
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
      Acked-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
      Cc: Vinod Koul <vinod.koul@linux.intel.com>
      Cc: devicetree-discuss@lists.ozlabs.org
      Cc: linux-arm-kernel@lists.infradead.org
      Signed-off-by: NVinod Koul <vinod.koul@intel.com>
      f9c6a655
    • A
      9p: turn fid->dlist into hlist · c4d30967
      Al Viro 提交于
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      c4d30967
    • S
      hlist: drop the node parameter from iterators · b67bfe0d
      Sasha Levin 提交于
      I'm not sure why, but the hlist for each entry iterators were conceived
      
              list_for_each_entry(pos, head, member)
      
      The hlist ones were greedy and wanted an extra parameter:
      
              hlist_for_each_entry(tpos, pos, head, member)
      
      Why did they need an extra pos parameter? I'm not quite sure. Not only
      they don't really need it, it also prevents the iterator from looking
      exactly like the list iterator, which is unfortunate.
      
      Besides the semantic patch, there was some manual work required:
      
       - Fix up the actual hlist iterators in linux/list.h
       - Fix up the declaration of other iterators based on the hlist ones.
       - A very small amount of places were using the 'node' parameter, this
       was modified to use 'obj->member' instead.
       - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
       properly, so those had to be fixed up manually.
      
      The semantic patch which is mostly the work of Peter Senna Tschudin is here:
      
      @@
      iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
      
      type T;
      expression a,c,d,e;
      identifier b;
      statement S;
      @@
      
      -T b;
          <+... when != b
      (
      hlist_for_each_entry(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_continue(a,
      - b,
      c) S
      |
      hlist_for_each_entry_from(a,
      - b,
      c) S
      |
      hlist_for_each_entry_rcu(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_rcu_bh(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_continue_rcu_bh(a,
      - b,
      c) S
      |
      for_each_busy_worker(a, c,
      - b,
      d) S
      |
      ax25_uid_for_each(a,
      - b,
      c) S
      |
      ax25_for_each(a,
      - b,
      c) S
      |
      inet_bind_bucket_for_each(a,
      - b,
      c) S
      |
      sctp_for_each_hentry(a,
      - b,
      c) S
      |
      sk_for_each(a,
      - b,
      c) S
      |
      sk_for_each_rcu(a,
      - b,
      c) S
      |
      sk_for_each_from
      -(a, b)
      +(a)
      S
      + sk_for_each_from(a) S
      |
      sk_for_each_safe(a,
      - b,
      c, d) S
      |
      sk_for_each_bound(a,
      - b,
      c) S
      |
      hlist_for_each_entry_safe(a,
      - b,
      c, d, e) S
      |
      hlist_for_each_entry_continue_rcu(a,
      - b,
      c) S
      |
      nr_neigh_for_each(a,
      - b,
      c) S
      |
      nr_neigh_for_each_safe(a,
      - b,
      c, d) S
      |
      nr_node_for_each(a,
      - b,
      c) S
      |
      nr_node_for_each_safe(a,
      - b,
      c, d) S
      |
      - for_each_gfn_sp(a, c, d, b) S
      + for_each_gfn_sp(a, c, d) S
      |
      - for_each_gfn_indirect_valid_sp(a, c, d, b) S
      + for_each_gfn_indirect_valid_sp(a, c, d) S
      |
      for_each_host(a,
      - b,
      c) S
      |
      for_each_host_safe(a,
      - b,
      c, d) S
      |
      for_each_mesh_entry(a,
      - b,
      c, d) S
      )
          ...+>
      
      [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
      [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
      [akpm@linux-foundation.org: checkpatch fixes]
      [akpm@linux-foundation.org: fix warnings]
      [akpm@linux-foudnation.org: redo intrusive kvm changes]
      Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
      Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
      Cc: Wu Fengguang <fengguang.wu@intel.com>
      Cc: Marcelo Tosatti <mtosatti@redhat.com>
      Cc: Gleb Natapov <gleb@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b67bfe0d
    • M
      include/linux/eventfd.h: fix incorrect filename is a comment · 1d730c49
      Martin Sustrik 提交于
      Comment in eventfd.h referred to 'include/asm-generic/fcntl.h'
      while the correct path is 'include/uapi/asm-generic/fcntl.h'.
      Signed-off-by: NMartin Sustrik <sustrik@250bpm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      1d730c49
    • A
      nbd: support FLUSH requests · 75f187ab
      Alex Bligh 提交于
      Currently, the NBD device does not accept flush requests from the Linux
      block layer.  If the NBD server opened the target with neither O_SYNC nor
      O_DSYNC, however, the device will be effectively backed by a writeback
      cache.  Without issuing flushes properly, operation of the NBD device will
      not be safe against power losses.
      
      The NBD protocol has support for both a cache flush command and a FUA
      command flag; the server will also pass a flag to note its support for
      these features.  This patch adds support for the cache flush command and
      flag.  In the kernel, we receive the flags via the NBD_SET_FLAGS ioctl,
      and map NBD_FLAG_SEND_FLUSH to the argument of blk_queue_flush.  When the
      flag is active the block layer will send REQ_FLUSH requests, which we
      translate to NBD_CMD_FLUSH commands.
      
      FUA support is not included in this patch because all free software
      servers implement it with a full fdatasync; thus it has no advantage over
      supporting flush only.  Because I [Paolo] cannot really benchmark it in a
      realistic scenario, I cannot tell if it is a good idea or not.  It is also
      not clear if it is valid for an NBD server to support FUA but not flush.
      The Linux block layer gives a warning for this combination, the NBD
      protocol documentation says nothing about it.
      
      The patch also fixes a small problem in the handling of flags: nbd->flags
      must be cleared at the end of NBD_DO_IT, but the driver was not doing
      that.  The bug manifests itself as follows.  Suppose you two different
      client/server pairs to start the NBD device.  Suppose also that the first
      client supports NBD_SET_FLAGS, and the first server sends
      NBD_FLAG_SEND_FLUSH; the second pair instead does neither of these two
      things.  Before this patch, the second invocation of NBD_DO_IT will use a
      stale value of nbd->flags, and the second server will issue an error every
      time it receives an NBD_CMD_FLUSH command.
      
      This bug is pre-existing, but it becomes much more important after this
      patch; flush failures make the device pretty much unusable, unlike
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NAlex Bligh <alex@alex.org.uk>
      Acked-by: NPaul Clements <Paul.Clements@steeleye.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      75f187ab
    • R
      ipmi: remove superfluous kernel/userspace explanation · 59fb1b9f
      Robert P. J. Day 提交于
      Given the obvious distinction between kernel and userspace supported
      by uapi/, it seems unnecessary to comment on that.
      Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
      Signed-off-by: NCorey Minyard <cminyard@mvista.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      59fb1b9f
    • T
      idr: implement lookup hint · 0ffc2a9c
      Tejun Heo 提交于
      While idr lookup isn't a particularly heavy operation, it still is too
      substantial to use in hot paths without worrying about the performance
      implications.  With recent changes, each idr_layer covers 256 slots
      which should be enough to cover most use cases with single idr_layer
      making lookup hint very attractive.
      
      This patch adds idr->hint which points to the idr_layer which
      allocated an ID most recently and the fast path lookup becomes
      
      	if (look up target's prefix matches that of the hinted layer)
      		return hint->ary[ID's offset in the leaf layer];
      
      which can be inlined.
      
      idr->hint is set to the leaf node on idr_fill_slot() and cleared from
      free_layer().
      
      [andriy.shevchenko@linux.intel.com: always do slow path when hint is uninitialized]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Sasha Levin <sasha.levin@oracle.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0ffc2a9c
    • T
      idr: add idr_layer->prefix · 54616283
      Tejun Heo 提交于
      Add a field which carries the prefix of ID the idr_layer covers.  This
      will be used to implement lookup hint.
      
      This patch doesn't make use of the new field and doesn't introduce any
      behavior difference.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      54616283