1. 28 Jul, 2010 6 commits
  2. 27 Jul, 2010 4 commits
    • Joe Eykholt's avatar
      [SCSI] libfc: fix indefinite rport restart · f034260d
      Joe Eykholt authored
      
      
      Remote ports were restarting indefinitely after getting
      rejects in PRLI.
      
      Fix by adding a counter of restarts and limiting that with
      the port login retry limit as well.
      Signed-off-by: default avatarJoe Eykholt <jeykholt@cisco.com>
      Signed-off-by: default avatarRobert Love <robert.w.love@intel.com>
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      f034260d
    • Joe Eykholt's avatar
      [SCSI] libfc: Fix remote port restart problem · 4b2164d4
      Joe Eykholt authored
      
      
      This patch somewhat combines two fixes to remote port handing in libfc.
      
      The first problem was that rport work could be queued on a deleted
      and freed rport.  This is handled by not resetting rdata->event
      ton NONE if the rdata is about to be deleted.
      
      However, that fix led to the second problem, described by
      Bhanu Gollapudi, as follows:
      > Here is the sequence of events. T1 is first LOGO receive thread, T2 is
      > fc_rport_work() scheduled by T1 and T3 is second LOGO receive thread and
      > T4 is fc_rport_work scheduled by T3.
      >
      > 1. (T1)Received 1st LOGO in state Ready
      > 2. (T1)Delete port & enter to RESTART state.
      > 3. (T1)schdule event_work, since event is RPORT_EV_NONE.
      > 4. (T1)set event = RPORT_EV_LOGO
      > 5. (T1)Enter RESTART state as disc_id is set.
      > 6. (T2)remember to PLOGI, and set event = RPORT_EV_NONE
      > 6. (T3)Received 2nd LOGO
      > 7. (T3)Delete Port & enter to RESTART state.
      > 8. (T3)schedule event_work, since event is RPORT_EV_NONE.
      > 9. (T3)Enter RESTART state as disc_id is set.
      > 9. (T3)set event = RPORT_EV_LOGO
      > 10.(T2)work restart, enter PLOGI state and issues PLOGI
      > 11.(T4)Since state is not RESTART anymore, restart is not set, and the
      > event is not reset to RPORT_EV_NONE. (current event is RPORT_EV_LOGO).
      > 12. Now, PLOGI succeeds and fc_rport_enter_ready() will not schedule
      > event_work, and hence the rport will never be created, eventually losing
      > the target after dev_loss_tmo.
      
      So, the problem here is that we were tracking the desire for
      the rport be restarted by state RESTART, which was otherwise
      equivalent to DELETE.  A contributing factor is that we dropped
      the lock between steps 6 and 10 in thread T2, which allows the
      state to change, and we didn't completely re-evaluate then.
      
      This is hopefully corrected by the following minor redesign:
      
      Simplify the rport restart logic by making the decision to
      restart after deleting the transport rport.  That decision
      is based on a new STARTED flag that indicates fc_rport_login()
      has been called and fc_rport_logoff() has not been called
      since then.  This replaces the need for the RESTART state.
      
      Only restart if the rdata is still in DELETED state
      and only if it still has the STARTED flag set.
      
      Also now, since we clear the event code much later in the
      work thread, allow for the possibility that the rport may
      have become READY again via incoming PLOGI, and if so,
      queue another event to handle that.
      
      In the problem scenario, the second LOGO received will
      cause the LOGO event to occur again.
      Reported-by: default avatarBhanu Gollapudi <bprakash@broadcom.com>
      Signed-off-by: default avatarJoe Eykholt <jeykholt@cisco.com>
      Signed-off-by: default avatarRobert Love <robert.w.love@intel.com>
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      4b2164d4
    • Bhanu Prakash Gollapudi's avatar
      [SCSI] libfc: Handle unsolicited PRLO request · f8fc6c2c
      Bhanu Prakash Gollapudi authored
      
      
      Resubmitting after incorporating Joe's review comment.
      
      Unsolicited PRLO request is now handled by sending LS_ACC,
      and then relogin to the remote port if an N-port login
      session exists for that remote port.
      
      Note that this patch should be applied on top of Joe Eykholt's
      "Fix remote port restart problem" patch.
      Signed-off-by: default avatarBhanu Prakash Gollapudi <bprakash@broadcom.com>
      Signed-off-by: default avatarRobert Love <robert.w.love@intel.com>
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      f8fc6c2c
    • Joe Eykholt's avatar
      [SCSI] fcoe: clean up TBD comments in FCoE prototype header · 5d4a2e29
      Joe Eykholt authored
      
      
      Some old comments in fc_fcoe.h say TBD long after the
      standard has been passed by T11.  Clean them up.
      Signed-off-by: default avatarJoe Eykholt <jeykholt@cisco.com>
      Signed-off-by: default avatarRobert Love <robert.w.love@intel.com>
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      5d4a2e29
  3. 02 Jun, 2010 1 commit
  4. 16 May, 2010 2 commits
  5. 02 May, 2010 1 commit
  6. 30 Apr, 2010 1 commit
  7. 11 Apr, 2010 6 commits
  8. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  9. 12 Mar, 2010 1 commit
  10. 03 Mar, 2010 1 commit
  11. 08 Feb, 2010 1 commit
  12. 18 Jan, 2010 1 commit
  13. 17 Jan, 2010 1 commit
  14. 30 Dec, 2009 1 commit
    • James Bottomley's avatar
      libsrp: fix compile failure · 75c85a0b
      James Bottomley authored
      commit 45465487
      
       ("kfifo: move struct
      kfifo in place") caused a compile failure in ibmvscsitgt.c because it
      changed a pointer to kfifo in the libsrp.h structure to a direct
      inclusion without including <linux/kfifo.h>.
      
      The fix is simple, just add the include, but how did this happen? This
      change, introduced at -rc2, hardly looks like a bug fix, and it clearly
      didn't go through linux-next, which would have picked up this compile
      failure (it only occurs on ppc because of the ibm virtual scsi target).
      
      [ Apparently all of -mm wasn't in linux-next.. ]
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      75c85a0b
  15. 22 Dec, 2009 1 commit
    • Stefani Seibold's avatar
      kfifo: move struct kfifo in place · 45465487
      Stefani Seibold authored
      
      
      This is a new generic kernel FIFO implementation.
      
      The current kernel fifo API is not very widely used, because it has to
      many constrains.  Only 17 files in the current 2.6.31-rc5 used it.
      FIFO's are like list's a very basic thing and a kfifo API which handles
      the most use case would save a lot of development time and memory
      resources.
      
      I think this are the reasons why kfifo is not in use:
      
       - The API is to simple, important functions are missing
       - A fifo can be only allocated dynamically
       - There is a requirement of a spinlock whether you need it or not
       - There is no support for data records inside a fifo
      
      So I decided to extend the kfifo in a more generic way without blowing up
      the API to much.  The new API has the following benefits:
      
       - Generic usage: For kernel internal use and/or device driver.
       - Provide an API for the most use case.
       - Slim API: The whole API provides 25 functions.
       - Linux style habit.
       - DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros
       - Direct copy_to_user from the fifo and copy_from_user into the fifo.
       - The kfifo itself is an in place member of the using data structure, this save an
         indirection access and does not waste the kernel allocator.
       - Lockless access: if only one reader and one writer is active on the fifo,
         which is the common use case, no additional locking is necessary.
       - Remove spinlock - give the user the freedom of choice what kind of locking to use if
         one is required.
       - Ability to handle records. Three type of records are supported:
         - Variable length records between 0-255 bytes, with a record size
           field of 1 bytes.
         - Variable length records between 0-65535 bytes, with a record size
           field of 2 bytes.
         - Fixed size records, which no record size field.
       - Preserve memory resource.
       - Performance!
       - Easy to use!
      
      This patch:
      
      Since most users want to have the kfifo as part of another object,
      reorganize the code to allow including struct kfifo in another data
      structure.  This requires changing the kfifo_alloc and kfifo_init
      prototypes so that we pass an existing kfifo pointer into them.  This
      patch changes the implementation and all existing users.
      
      [akpm@linux-foundation.org: fix warning]
      Signed-off-by: default avatarStefani Seibold <stefani@seibold.net>
      Acked-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      Acked-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
      Acked-by: default avatarAndi Kleen <ak@linux.intel.com>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      45465487
  16. 10 Dec, 2009 1 commit
    • Boaz Harrosh's avatar
      [SCSI] libosd: Fix blk_put_request locking again · 5d0961fd
      Boaz Harrosh authored
      
      
      So libosd has decided to sacrifice some code simplicity for the sake of
      a clean API. One of these things is the possibility for users to call
      osd_end_request, in any condition at any state. This opens up some
      problems with calling blk_put_request when out-side of the completion
      callback but calling __blk_put_request when detecting a from-completion
      state.
      
      The current hack was working just fine until exofs decided to operate on
      all devices in parallel and wait for the sum of the requests, before
      deallocating all osd-requests at once. There are two new possible cases
      1. All request in a group are deallocated as part of the last request's
         async-done, request_queue is locked.
      2. All request in a group where executed asynchronously, but
         de-allocation was delayed to after the async-done, in the context of
         another thread. Async execution but request_queue is not locked.
      
      The solution I chose was to separate the deallocation of the osd_request
      which has the information users need, from the deallocation of the
      internal(2) requests which impose the locking problem. The internal
      block-requests are freed unconditionally inside the async-done-callback,
      when we know the queue is always locked. If at osd_end_request time we
      still have a bock-request, then we know it did not come from within an
      async-done-callback and we can call the regular blk_put_request.
      
      The internal requests were used for carrying error information after
      execution. This information is now copied to osd_request members for
      later analysis by user code.
      
      The external API and behaviour was unchanged, except now it really
      supports what was previously advertised.
      Reported-by: default avatarVineet Agarwal <checkout.vineet@gmail.com>
      Signed-off-by: default avatarBoaz Harrosh <bharrosh@panasas.com>
      Cc: Stable Tree <stable@kernel.org>
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      5d0961fd
  17. 04 Dec, 2009 10 commits