Commit graph

112 commits

Author SHA1 Message Date
Mike Snitzer
7e8a74b177 [SCSI] scsi_dh: add scsi_dh_attached_handler_name
Introduce scsi_dh_attached_handler_name() to retrieve the name of the
scsi_dh that is attached to the scsi_device associated with the provided
request queue.  Returns NULL if a scsi_dh is not attached.

Also, fix scsi_dh_{attach,detach} function header comments to document
@q rather than @sdev.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:42 +01:00
Bart Van Assche
bb2c94a3a6 [SCSI] scsi_dh_alua: Re-enable STPG for unavailable ports
A quote from SPC-4: "While in the unavailable primary target port
asymmetric access state, the device server shall support those of
the following commands that it supports while in the active/optimized
state: [ ... ] d) SET TARGET PORT GROUPS; [ ... ]". Hence re-enable
sending STPG to a target port group that is in the unavailable state.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Babu Moger <babu.moger@netapp.com> 
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:36 +01:00
Rob Evers
bc97f4bb44 [SCSI] scsi_dh_alua: backoff alua rtpg retry linearly vs. geometrically
Currently the backoff algorithm for when to retry alua rtpg
requests progresses geometrically as so:

2, 4, 8, 16, 32, 64... seconds.

This progression can lead to un-needed delay in retrying
alua rtpg requests when the rtpgs are delayed.  A less
aggressive backoff algorithm that is additive would not
lead to such large jumps when delays start getting long, but
would backoff linearly:

2, 4, 6, 8, 10... seconds.

Signed-off-by: Martin George <marting@netapp.com>
Signed-off-by: Rob Evers <revers@redhat.com>
Reviewed-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:33 +01:00
Rob Evers
8e67ce6072 [SCSI] scsi_dh_alua: retry alua rtpg extended header for illegal request response
Some storage arrays are known to return 'illegal request'
when an rtpg extended header request is made.  T10 says the
array should ignore the bit, and return the non-extended
rtpg as the array doesn't support the request.  Working
around this by retrying the rtpg request without the extended
header bit set when the extended rtpg request results in
illegal request.

Signed-off-by: Rob Evers <revers@redhat.com>
Reviewed-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:33 +01:00
Rob Evers
3588c5a21a [SCSI] scsi_dh_alua: implement 'implied transition timeout'
During alua transitions, an array can return transitioning
status in response to rtpg requests.  These requests get
retried for a maximum of 60 seconds by default before timing
out.  Sometimes this timeout isn't sufficient to allow the
array to complete the transition.  T10-spc4 addresses this
under 'Report Target Port Groups' command.

This update retrieves the timeout value from the storage
array if available and retries the transitioning rtpgs
for up to the 'implied transitioning timeout' value

Signed-off-by: Rob Evers <revers@redhat.com>
Reviewed-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:32 +01:00
Moger, Babu
72d9e0f383 [SCSI] scsi_dh_alua: Optimize the STPG command
This patch optimizes the set target port group(STPG) command. During our
testing, we found that it is not optimal to send stpg command every time
the path group switch happens. This patch uses PREF (preferred target port)
bit with combination of flags passed by multipath user level tool to
optimize this behaviour. If PREF bit is set then it issues a STPG command,
otherwise it will let implicit transfer take place.

By default there is no change in the behaviour. User tool needs to pass the
parameter to make this change take effect. Patch has been tested on NetApp
E series storage.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 19:28:18 +01:00
Moger, Babu
dcd3a754b8 [SCSI] scsi_dh_alua: Store the PREF bit from RTPG
PREF bit indicates preferred target port group for accessing a logical
unit. This bit is used to optimize the STPG command handling.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 19:28:13 +01:00
Moger, Babu
4335d092a1 [SCSI] scsi_dh_alua: Inroduce the set_params interface scsi_dh_alua handler
Handler expects only one parameter to set the flag ALUA_OPTIMIZE_STPG.
This flag is used to optimize the STPG behaviour. There is no change in
behaviour by default.

For example, to set the flag pass the following parameters from multipath.conf
hardware_handler        "2 alua 1"

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 19:28:07 +01:00
Moger, Babu
3569e5374d [SCSI] scsi_dh_rdac: Fix for unbalanced reference count
This patch fixes an unbalanced refcount issue.

Elevating the lock for both kref_put and also for controller node deletion.
Previously, controller deletion was protected but the not the kref_put. This
was causing the other thread to pick up the controller structure which was
already kref'd zero.

This was causing the following WARN_ON and also sometimes panic.

WARNING: at lib/kref.c:43 kref_get+0x2d/0x30() (Not tainted)
Hardware name: IBM System x3655 -[7985AC1]-
Modules linked in: fuse scsi_dh_rdac autofs4 nfs lockd fscache nfs_acl
auth_rpcgss sunrpc 8021q garp stp llc ipv6 ib_srp(U) scsi_transport_srp
scsi_tgt ib_cm(U) ib_sa(U) ib_uverbs(U) ib_umad(U) mlx4_ib(U) mlx4_core(U)
ib_mthca(U) ib_mad(U) ib_core(U) dm_mirror dm_region_hash dm_log dm_round_robin
dm_multipath uinput bnx2 ses enclosure sg ibmpex ibmaem ipmi_msghandler
serio_raw k8temp hwmon amd64_edac_mod edac_core edac_mce_amd shpchp i2c_piix4
ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif sata_svw pata_acpi ata_generic
pata_serverworks aacraid radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core
dm_mod [last unloaded: freq_table]
Pid: 13735, comm: srp_daemon Not tainted 2.6.32-71.el6.x86_64 #1
Call Trace:
[<ffffffff8106b857>] warn_slowpath_common+0x87/0xc0
[<ffffffff8106b8aa>] warn_slowpath_null+0x1a/0x20
[<ffffffff8125c39d>] kref_get+0x2d/0x30
[<ffffffffa01b4029>] rdac_bus_attach+0x459/0x580 [scsi_dh_rdac]
[<ffffffff8135232a>] scsi_dh_handler_attach+0x2a/0x80
[<ffffffff81352c7b>] scsi_dh_notifier+0x9b/0xa0
[<ffffffff814cd7a5>] notifier_call_chain+0x55/0x80
[<ffffffff8109711a>] __blocking_notifier_call_chain+0x5a/0x80
[<ffffffff81097156>] blocking_notifier_call_chain+0x16/0x20
[<ffffffff8132bec5>] device_add+0x515/0x640
[<ffffffff813329e4>] ? attribute_container_device_trigger+0xc4/0xe0
[<ffffffff8134f659>] scsi_sysfs_add_sdev+0x89/0x2c0
[<ffffffff8134d096>] scsi_probe_and_add_lun+0xea6/0xed0
[<ffffffff8134beb2>] ? scsi_alloc_target+0x292/0x2d0
[<ffffffff8134d1e1>] __scsi_scan_target+0x121/0x750
[<ffffffff811df806>] ? sysfs_create_file+0x26/0x30
[<ffffffff8132b759>] ? device_create_file+0x19/0x20
[<ffffffff81332838>] ? attribute_container_add_attrs+0x78/0x90
[<ffffffff814b008c>] ? klist_next+0x4c/0xf0
[<ffffffff81332e30>] ? transport_configure+0x0/0x20
[<ffffffff813329e4>] ? attribute_container_device_trigger+0xc4/0xe0
[<ffffffff8134df40>] scsi_scan_target+0xd0/0xe0
[<ffffffffa02f053a>] srp_create_target+0x75a/0x890 [ib_srp]
[<ffffffff8132a130>] dev_attr_store+0x20/0x30
[<ffffffff811df145>] sysfs_write_file+0xe5/0x170
[<ffffffff8116c818>] vfs_write+0xb8/0x1a0
[<ffffffff810d40a2>] ? audit_syscall_entry+0x272/0x2a0
[<ffffffff8116d251>] sys_write+0x51/0x90
[<ffffffff81013172>] system_call_fastpath+0x16/0x1b

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-22 12:15:19 -06:00
Moger, Babu
410f02d813 [SCSI] scsi_dh_alua: Retry the check-condition in case Mode Parameters Changed
This patch adds a check-condition in scsi_dh_alua handler for a retry.
Sometimes, I have seen attach failing due to this check-condition with
following error messages on NetApp E series storage.

Dec  7 15:31:01 nilgiris kernel: [102979.696673] scsi 3:0:2:9: alua: port group 00 rel port 01
Dec  7 15:31:01 nilgiris kernel: [102979.697082] scsi 3:0:2:9: alua: rtpg failed with 8000002
Dec  7 15:31:01 nilgiris kernel: [102979.697086] scsi 3:0:2:9: alua: rtpg sense code 06/2a/01
Dec  7 15:31:01 nilgiris kernel: [102979.697088] scsi 3:0:2:9: alua: not attached

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-01-10 17:01:24 -06:00
Richard Weinberger
9fc397fc08 [SCSI] scsi_dh_rdac: Fix error path
If create_singlethread_workqueue() failes, rdac_init should fail too.

Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: "Moger, Babu" <Babu.Moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-01-10 17:01:18 -06:00
Moger, Babu
2b132577a0 [SCSI] scsi_dh: code cleanup and remove the references to scsi_dev_info
All the handlers have now implemented the match function so We don't need to
use scsi_dev_info any more for matching purposes.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-12-15 10:55:00 +04:00
Moger, Babu
bee89eae8d [SCSI] scsi_dh_rdac: Adding the match function for rdac device handler
This patch introduces the match function for rdac device handler. Without
this, sometimes handler attach fails during the device_add. Included check for
TPGS bit before proceeding further. The match function was introduced by
commit 6c3633d08a

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-12-15 10:55:00 +04:00
Moger, Babu
a315969e8d [SCSI] scsi_dh_hp_sw: Adding the match function for hp_sw device handler
This patch introduces the match function for hp_sw device handler.  Included
the check for TPGS bit before proceeding further per Hannes comment.  The
match function was introduced by commit
6c3633d08a

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-12-15 10:55:00 +04:00
Moger, Babu
4f10143f6e [SCSI] scsi_dh_emc: Add a match function for emc device handler
This patch introduces the match function for emc device handler.  Included
check for TPGS bit before proceeding further.  The match function was
introduced by commit 6c3633d08a

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-12-15 10:55:00 +04:00
Linus Torvalds
32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00
Moger, Babu
ab72002bc5 [SCSI] scsi_dh_alua: Fix the time inteval for alua rtpg commands
This patch corrects the retry interval for alua rtpg command. Purpose was to retry the commands in seconds.
But that was not happening. Reason is msleep takes argument in milliseconds.

Also added minor text after successful attach.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-11-03 11:18:10 +04:00
Paul Gortmaker
acf3368ffb scsi: Fix up files implicitly depending on module.h inclusion
The module.h header was implicitly present everywhere, so files
with no explicit include of the module infrastructure would build
anyway.  We are now removing the implicit include, and so we need
to call out the module.h file that we need explicitly.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:24 -04:00
Moger, Babu
a18a920c70 [SCSI] scsi_dh: check queuedata pointer before proceeding further
This patch validates sdev pointer in scsi_dh_activate before proceeding further.

Without this check we might see the panic as below. I have seen this
panic multiple times..

Call trace:

 #0 [ffff88007d647b50] machine_kexec at ffffffff81020902
 #1 [ffff88007d647ba0] crash_kexec at ffffffff810875b0
 #2 [ffff88007d647c70] oops_end at ffffffff8139c650
 #3 [ffff88007d647c90] __bad_area_nosemaphore at ffffffff8102dd15
 #4 [ffff88007d647d50] page_fault at ffffffff8139b8cf
    [exception RIP: scsi_dh_activate+0x82]
    RIP: ffffffffa0041922  RSP: ffff88007d647e00  RFLAGS: 00010046
    RAX: 0000000000000000  RBX: 0000000000000000  RCX: 00000000000093c5
    RDX: 00000000000093c5  RSI: ffffffffa02e6640  RDI: ffff88007cc88988
    RBP: 000000000000000f   R8: ffff88007d646000   R9: 0000000000000000
    R10: ffff880082293790  R11: 00000000ffffffff  R12: ffff88007cc88988
    R13: 0000000000000000  R14: 0000000000000286  R15: ffff880037b845e0
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
 #5 [ffff88007d647e38] run_workqueue at ffffffff81060268
 #6 [ffff88007d647e78] worker_thread at ffffffff81060386
 #7 [ffff88007d647ee8] kthread at ffffffff81064436
 #8 [ffff88007d647f48] kernel_thread at ffffffff81003fba

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-31 13:10:36 +04:00
Moger, Babu
bf81973a5d [SCSI] scsi_dh_alua: Add one more check-condition for alua handler
This patch adds one more check-condition for scsi_dh_alua handler. Without
this, the handler attach fails sometimes during the discovery. I have noticed
this with NetApp E-Series storage with alua mode. Also removed some
unnecessary brackets {} for consistency.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-16 10:57:27 -05:00
Chauhan, Vijay
5f7a643304 [SCSI] scsi_dh_rdac: Adding NetApp as a brand name for rdac
Signed-off-by: Vijay Chauhan <Vijay.chauhan@netapp.com>
Reviewed-by: Bob Stankey <Robert.stankey@netapp.com>
Reviewed-by: Babu Moger <Babu.moger@netapp.com>
Acked-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-09-22 15:26:43 +04:00
Moger, Babu
66195fc9fa [SCSI] scsi_dh_rdac: Adding couple more vendor product ids
This patch adds couple more Vendor/Product IDs for RDAC.. There are no
functional changes.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-09-22 15:02:57 +04:00
Hannes Reinecke
ebd1f645bd [SCSI] scsi_dh_alua: Decrease retry interval
The alua device handler starts the first retry after 10 seconds,
and increases it times 10 for each round.
This leads to an unnecessary delay. This patch modifies it to
start after one second, and increase by a factor of two.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:33:06 -07:00
Hannes Reinecke
cfde3fa166 [SCSI] scsi_dh_alua: Fix Erroneous TPG ID check
For Target Portal Group IDs occupying the full 2 bytes in the
RTPG response, the following group_id check in the alua_rtpg
routine always fails in scsi_dh_alua.c:

if (h->group_id == (ucp[2] << 8) + ucp[3]) {

This causes the ALUA handler to wrongly identify the AAS of
a specified device as well as incorrectly interpreting the
supported AAS of the target as seen by the following entries
in the /var/log/messages:

"alua: port group 3ea state A supports tousna"
"alua: port group 3e9 state A supports tousna"

This is because 'ucp' is wrongly declared in alua_rtpg as
a character pointer instead of an unsigned character pointer.

Signed-off-by: Martin George <marting@netapp.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:32:41 -07:00
Hannes Reinecke
6bc8d2a0c6 [SCSI] scsi_dh: Check for sdev state in store_dh_state()
Avoid attaching a hardware handler to a device which is
already scheduled for deletion.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:31:24 -07:00
Hannes Reinecke
46ccf6b55b [SCSI] scsi_dh_alua: always update TPGS status on activate
When activating a patch we should always update the TPGS state
as it might have changed in between.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:31:03 -07:00
Hannes Reinecke
6c3633d08a [SCSI] scsi_dh: Implement match callback function
Some device handler types are not tied to the vendor/model
but rather to a specific capability. Eg ALUA is supported
if the 'TPGS' setting in the standard inquiry is set.
This patch implements a 'match' callback for device handler
which supersedes the original vendor/model lookup and
implements the callback for the ALUA handler.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:28:30 -07:00
Hannes Reinecke
2a9ab40f74 [SCSI] scsi_dh: Fixup kernel-doc comments
Fixup some kernel-doc comments to reference to the
correct function name.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:27:41 -07:00
Hannes Reinecke
d7c48feb38 [SCSI] scsi_dh_alua: Evaluate TPGS setting from inquiry data
Instead of issuing a standard inquiry from within the
alua device handler we can evaluate the TPGS setting from
the existing inquiry data of the sdev and save us the I/O.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:26:49 -07:00
Chandra Seetharaman
d685759539 [SCSI] dh_rdac: Associate HBA and storage in rdac_controller to support partitions in storage
rdac hardware handler assumes that there is one-to-one relation ship
between the host and the controller w.r.t lun.  IOW, it does not
support "multiple storage partitions" within a storage.

Example:
HBA1 and HBA2 see lun 0 and 1 in storage A (1)
HBA3 and HBA4 see lun 0 and 1 in storage A (2)
HBA5 and HBA6 see lun 0 and 1 in storage A (3)

luns 0 and 1 in (1), (2) and (3) are totally different.

But, rdac handler treats the lun 0s (and lun 1s) as the same when
sending a mode select to the controller, which is wrong.

This patch makes the rdac hardware handler associate HBA and the
storage w.r.t lun (and not the host itself).

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-28 11:38:47 +04:00
Chandra Seetharaman
a53becc9a9 [SCSI] dh_rdac: Use WWID from C8 page instead of Subsystem id from C4 page to identify storage
rdac hardware handler uses "Subsystem Identifier" from C4 inquiry page
to uniquely identify a storage. The problem with that is that if any
any of the bytes are non-ascii, subsys_id will all be spaces (hex
0x20). This creates lot of problems especially when there are multiple
rdac storages are connected to the server.

Use "Storage Array Unique Identifier" from C8 inquiry page, which is the
world wide unique identifier for the storage array, to uniquely identify
the storage.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-27 14:29:44 +04:00
Phil Carmody
497888cf69 treewide: fix potentially dangerous trailing ';' in #defined values/expressions
All these are instances of
  #define NAME value;
or
  #define NAME(params_opt) value;

These of course fail to build when used in contexts like
  if(foo $OP NAME)
  while(bar $OP NAME)
and may silently generate the wrong code in contexts such as
  foo = NAME + 1;    /* foo = value; + 1; */
  bar = NAME - 1;    /* bar = value; - 1; */
  baz = NAME & quux; /* baz = value; & quux; */

Reported on comp.lang.c,
Message-ID: <ab0d55fe-25e5-482b-811e-c475aa6065c3@c29g2000yqd.googlegroups.com>
Initial analysis of the dangers provided by Keith Thompson in that thread.

There are many more instances of more complicated macros having unnecessary
trailing semicolons, but this pile seems to be all of the cases of simple
values suffering from the problem. (Thus things that are likely to be found
in one of the contexts above, more complicated ones aren't.)

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-07-21 14:10:00 +02:00
Linus Torvalds
ad9471752e Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (110 commits)
  [SCSI] qla2xxx: Refactor call to qla2xxx_read_sfp for thermal temperature.
  [SCSI] qla2xxx: Unify the read/write sfp mailbox command routines.
  [SCSI] qla2xxx: Clear complete initialization control block.
  [SCSI] qla2xxx: Allow an override of the registered maximum LUN.
  [SCSI] qla2xxx: Add host number in reset and quiescent message logs.
  [SCSI] qla2xxx: Correctly read sfp single byte mailbox register.
  [SCSI] qla2xxx: Add qla82xx_rom_unlock() function.
  [SCSI] qla2xxx: Log if qla82xx firmware fails to load from flash.
  [SCSI] qla2xxx: Use passed in host to initialize local scsi_qla_host in queuecommand function
  [SCSI] qla2xxx: Correct buffer start in edc sysfs debug print.
  [SCSI] qla2xxx: Update firmware version after flash update for ISP82xx.
  [SCSI] qla2xxx: Fix hang during driver unload when vport is active.
  [SCSI] qla2xxx: Properly set the dsd_list_len for dsd_chaining in cmd type 6.
  [SCSI] qla2xxx: Fix virtual port failing to login after chip reset.
  [SCSI] qla2xxx: Fix vport delete hang when logins are outstanding.
  [SCSI] hpsa: Change memset using sizeof(ptr) to sizeof(*ptr)
  [SCSI] ipr: Rate limit DMA mapping errors
  [SCSI] hpsa: add P2000 to list of shared SAS devices
  [SCSI] hpsa: do not attempt PCI power management reset method if we know it won't work.
  [SCSI] hpsa: remove superfluous sleeps around reset code
  ...
2011-05-20 13:29:52 -07:00
Martin George
c0d289b3e5 [SCSI] scsi_dh_alua: Attach to UNAVAILABLE/OFFLINE AAS devices
The SCSI ALUA handler currently fails to attach to devices
reporting an UNAVAILABLE/OFFLINE AAS. But given that an
UNAVAILABLE/OFFLINE AAS can transition to other states
like ACTIVE/OPTIMIZED, ACTIVE/NON-OPTIMIZED, etc. as per
SPC4, this ALUA handler behavior should be rectified so
as to attach to devices which also report an
UNAVAILABLE/OFFLINE AAS.

Signed-off-by: Martin George <marting@netapp.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-05-01 12:05:40 -05:00
Moger, Babu
3425fbfe22 [SCSI] scsi_dh_rdac : decide whether to send mode select based on operating mode
Based on the operating modes, handler decides whether to send mode
select or not. Purpose here is to reduce io-shipping as much as
possible whenever there is an option.

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Reviewed-by: Yanling Qi <yanling.qi@lsi.com>
Reviewed-by: Sudhir Dachepalli <Sudhir.Dachepalli@lis.com>
Reviewed-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Reviewed-by: Bob Stankey <Robert.Stankey@lsi.com>
Reviewed-by: Vijay Chauhan <Vijay.Chauhan@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-05-01 10:47:41 -05:00
Moger, Babu
1c3afc4234 [SCSI] scsi_dh_rdac : Detect the different RDAC operating modes
This patch detects different operating RDAC modes during the
discovery. It also collects the information about the preferred path.

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Reviewed-by: Yanling Qi <yanling.qi@lsi.com>
Reviewed-by: Sudhir Dachepalli <Sudhir.Dachepalli@lis.com>
Reviewed-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Reviewed-by: Bob Stankey <Robert.Stankey@lsi.com>
Reviewed-by: Vijay Chauhan <Vijay.Chauhan@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-05-01 10:46:57 -05:00
Moger, Babu
eebe9b96dd [SCSI] scsi_dh_rdac : Add definitions for different RDAC operating modes
This patch adds definitions to support for different operating modes
for LSI rdac storage.  Currently, rdac support 3 operation modes.

1. RDAC mode(legacy)
2. AVT mode
3. IOSHIP mode

These definitions are used while activating the path(rdac_activate).

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Reviewed-by: Yanling Qi <yanling.qi@lsi.com>
Reviewed-by: Sudhir Dachepalli <Sudhir.Dachepalli@lis.com>
Reviewed-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Reviewed-by: Bob Stankey <Robert.Stankey@lsi.com>
Reviewed-by: Vijay Chauhan <Vijay.Chauhan@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-05-01 10:45:22 -05:00
Mike Snitzer
0b8393578c [SCSI] scsi_dh: fix reference counting in scsi_dh_activate error path
Commit db422318cb ([SCSI] scsi_dh:
propagate SCSI device deletion) introduced a regression where the device
reference is not dropped prior to scsi_dh_activate's early return from
the error path.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org # 2.6.38
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-04-24 11:02:09 -05:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Yanqing_Liu@Dell.com
bc898c97f7 [SCSI] scsi_dh_rdac: Add MD36xxf into device list
This patch is to add Dell MD36xxf array into the RDAC handler device list.

Singed-off-by: Yanqing Liu <Yanqing_Liu@Dell.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-14 19:05:07 -05:00
Moger, Babu
a0b990c62c [SCSI] scsi_dh_rdac : Adding MODULE VERSION for rdac device handler
Adding MODULE_VERSION for scsi_dh_rdac. This will be helpful sometimes
to get the code level without looking at the code.

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 14:14:11 -06:00
Hillf Danton
9dfeb3157e [SCSI] scsi_dh: cosmetic change to sizeof()
instead of doing sizeof(struct X) it's better to do sizeof(*v) where v
is the variable pointing to struct X.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 14:13:34 -06:00
Moger, Babu
04b6e153b6 [SCSI] scsi_dh_rdac: fix for lun_table update for rdac device handler
During one of our testing, we noticed that mode select command sent
from the host did not have the lun_table updated.

Problem is root caused to the way lun table is updated. Lun table
update was done after the call to blk_rq_map_kern is made. This was
causing problem because kernel uses bounce buffer(bio_copy_kern) if
the address is not aligned.  The command buffer updated after the
call(blk_rq_map_kern) was not going on the wire. Moved the code to
update the lun_table before the call to fix the problem.

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Signed-off-by: Yanling Qi <Yanling.Qi@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 14:05:08 -06:00
Mike Snitzer
7a1e9d829f [SCSI] scsi_dh_hp_sw: fix deadlock in start_stop_endio
The use of blk_execute_rq_nowait() implies __blk_put_request() is needed
in start_stop_endio() rather than blk_put_request() --
blk_finish_request() is called with queue lock already held.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 10:31:04 -06:00
Peter Jones
940d7faa48 [SCSI] scsi_dh: Use scsi_devinfo functions to do matching of device_handler tables.
Previously we were using strncmp in order to avoid having to include
whitespace in the devlist, but this means "HSV1000" matches a device
list entry that says "HSV100", which is wrong.  This patch changes
scsi_dh.c to use scsi_devinfo's matching functions instead, since they
handle these cases correctly.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 12:02:09 -06:00
Mike Snitzer
5fd1062fdf [SCSI] scsi_dh_alua: add scalable ONTAP lun to dev list
Currently NetApp's VID/PID details in the INQUIRY response shows up as
'NETAPP' and 'LUN'.  With upcoming scalable SAN ONTAP version on NetApp
controllers, the PID entry alone is being modified to 'LUN C-Mode' (to
distinguish current ONTAP LUNs from scalable ONTAP LUNs).

'LUN' would still suffice for matching 'LUN C-Mode' but best to
explicitly add these new NetApp LUNs to the device list.

Reported-by: Martin George <marting@netapp.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 11:13:48 -06:00
Ilgu Hong
a3b1eff70b [SCSI] scsi_dh_alua: Add Promise VTrak to dev list
Adds Promise VTrak devices to the ALUA device handler.

Signed-off-by: Ilgu Hong <ilgu.hong@promise.com>
Signed-off-by: Joseph Gruher <joseph.r.gruher@intel.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 11:13:37 -06:00
Joseph Gruher
9349923d3f [SCSI] scsi_dh_alua: fix stpg_endio group state reporting
Initialize stpg_endio() 'err' to SCSI_DH_OK and only change it to
SCSI_DH_IO accordingly.  This allows the switching of target group state
to be properly reported when no error has occurred.

Signed-off-by: Joseph Gruher <joseph.r.gruher@intel.com>
Signed-off-by: Ilgu Hong <ilgu.hong@promise.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 11:13:25 -06:00
Joseph Gruher
ed0f36bc57 [SCSI] scsi_dh_alua: fix deadlock in stpg_endio
The use of blk_execute_rq_nowait() implies __blk_put_request() is needed
in stpg_endio() rather than blk_put_request() -- blk_finish_request() is
called with queue lock already held.

Signed-off-by: Joseph Gruher <joseph.r.gruher@intel.com>
Signed-off-by: Ilgu Hong <ilgu.hong@promise.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 11:13:13 -06:00
Joseph Gruher
7c66e9a5e6 [SCSI] scsi_dh_alua: fix submit_stpg return
submit_stpg() will always return failure so alua_activate() will report
failure via dm-multipath callback function.  Even though the stpg fired
successfuly dm-multipath does not know and always fails to change the
valid path.

By returning SCSI_DH_OK we're now skipping alua_activate()'s call to
activate_complete 'fn'.  But this is fine because stpg_endio() will call
it via h->callback_fn().

Signed-off-by: Joseph Gruher <joseph.r.gruher@intel.com>
Signed-off-by: Ilgu Hong <ilgu.hong@promise.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 11:11:58 -06:00