Commit Graph

146 Commits

Author SHA1 Message Date
Hannes Reinecke 345e29608b scsi: scsi: Export blacklist flags to sysfs
Each scsi device is scanned according to the found blacklist flags, but
this information is never presented to sysfs.  This makes it quite hard
to figure out if blacklisting worked as expected.  With this patch we're
exporting an additional attribute 'blacklist' containing the blacklist
flags for this device.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-10-17 00:57:12 -04:00
Hannes Reinecke 2930f81713 scsi: scsi_dh: suppress errors from unsupported devices
Device handlers are optional, and for some handlers like ALUA only
implemented for certain device types.  So suppress any errors for
unsupported devices.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-09-25 19:03:22 -04:00
Bart Van Assche ccf1e0045e scsi: Rework handling of scsi_device.vpd_pg8[03]
Introduce struct scsi_vpd for the VPD page length, data and the RCU head
that will be used to free the VPD data. Use kfree_rcu() instead of
kfree() to free VPD data. Move the VPD buffer pointer check inside the
RCU read lock in the sysfs code. Only annotate pointers that are shared
across threads with __rcu. Use rcu_dereference() when dereferencing an
RCU pointer. This patch suppresses about twenty sparse complaints about
the vpd_pg8[03] pointers. This patch also fixes a race condition, namely
that updating of the VPD pointers and length variables in struct
scsi_device was not atomic with reference to the code reading these
variables. See also "Does the update code tolerate concurrent accesses?"
in Documentation/RCU/checklist.txt.

Fixes: commit 09e2b0b146 ("scsi: rescan VPD attributes")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-29 21:51:42 -04:00
Bart Van Assche 3991e4605d scsi: Convert a strncmp() call into a strcmp() call
This patch avoids that smatch reports the following warning:

drivers/scsi/scsi_sysfs.c:117: check_set() error: strncmp() '"-"' too small (2 vs 20)

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-25 17:08:07 -04:00
weiping zhang 92227b8d3d scsi: scsi-sysfs: Adjust error returned for adapter reset request
If scsi_host_template->host_reset is NULL and the user requests an
adapter reset through

	echo adapter > /sys/class/scsi_host/hostx/host_reset

-EINVAL will be returned even though the "adapter" argument is perfectly
valid.

Change this so that we only return -EINVAL if the provided string is
invalid.  If the host does not implement a ->host_reset function we'll
return -EOPNOTSUPP.

[mkp: tweaked patch description]

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-24 22:29:06 -04:00
Ewan D. Milne f9279c968c scsi: Add STARGET_CREATED_REMOVE state to scsi_target_state
The addition of the STARGET_REMOVE state had the side effect of
introducing a race condition that can cause a crash.

scsi_target_reap_ref_release() checks the starget->state to
see if it still in STARGET_CREATED, and if so, skips calling
transport_remove_device() and device_del(), because the starget->state
is only set to STARGET_RUNNING after scsi_target_add() has called
device_add() and transport_add_device().

However, if an rport loss occurs while a target is being scanned,
it can happen that scsi_remove_target() will be called while the
starget is still in the STARGET_CREATED state.  In this case, the
starget->state will be set to STARGET_REMOVE, and as a result,
scsi_target_reap_ref_release() will take the wrong path.  The end
result is a panic:

[ 1255.356653] Oops: 0000 [#1] SMP
[ 1255.360154] Modules linked in: x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel ghash_clmulni_i
[ 1255.393234] CPU: 5 PID: 149 Comm: kworker/u96:4 Tainted: G        W       4.11.0+ #8
[ 1255.401879] Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
[ 1255.410327] Workqueue: scsi_wq_6 fc_scsi_scan_rport [scsi_transport_fc]
[ 1255.417720] task: ffff88060ca8c8c0 task.stack: ffffc900048a8000
[ 1255.424331] RIP: 0010:kernfs_find_ns+0x13/0xc0
[ 1255.429287] RSP: 0018:ffffc900048abbf0 EFLAGS: 00010246
[ 1255.435123] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 1255.443083] RDX: 0000000000000000 RSI: ffffffff8188d659 RDI: 0000000000000000
[ 1255.451043] RBP: ffffc900048abc10 R08: 0000000000000000 R09: 0000012433fe0025
[ 1255.459005] R10: 0000000025e5a4b5 R11: 0000000025e5a4b5 R12: ffffffff8188d659
[ 1255.466972] R13: 0000000000000000 R14: ffff8805f55e5088 R15: 0000000000000000
[ 1255.474931] FS:  0000000000000000(0000) GS:ffff880616b40000(0000) knlGS:0000000000000000
[ 1255.483959] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1255.490370] CR2: 0000000000000068 CR3: 0000000001c09000 CR4: 00000000000406e0
[ 1255.498332] Call Trace:
[ 1255.501058]  kernfs_find_and_get_ns+0x31/0x60
[ 1255.505916]  sysfs_unmerge_group+0x1d/0x60
[ 1255.510498]  dpm_sysfs_remove+0x22/0x60
[ 1255.514783]  device_del+0xf4/0x2e0
[ 1255.518577]  ? device_remove_file+0x19/0x20
[ 1255.523241]  attribute_container_class_device_del+0x1a/0x20
[ 1255.529457]  transport_remove_classdev+0x4e/0x60
[ 1255.534607]  ? transport_add_class_device+0x40/0x40
[ 1255.540046]  attribute_container_device_trigger+0xb0/0xc0
[ 1255.546069]  transport_remove_device+0x15/0x20
[ 1255.551025]  scsi_target_reap_ref_release+0x25/0x40
[ 1255.556467]  scsi_target_reap+0x2e/0x40
[ 1255.560744]  __scsi_scan_target+0xaa/0x5b0
[ 1255.565312]  scsi_scan_target+0xec/0x100
[ 1255.569689]  fc_scsi_scan_rport+0xb1/0xc0 [scsi_transport_fc]
[ 1255.576099]  process_one_work+0x14b/0x390
[ 1255.580569]  worker_thread+0x4b/0x390
[ 1255.584651]  kthread+0x109/0x140
[ 1255.588251]  ? rescuer_thread+0x330/0x330
[ 1255.592730]  ? kthread_park+0x60/0x60
[ 1255.596815]  ret_from_fork+0x29/0x40
[ 1255.600801] Code: 24 08 48 83 42 40 01 5b 41 5c 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90
[ 1255.621876] RIP: kernfs_find_ns+0x13/0xc0 RSP: ffffc900048abbf0
[ 1255.628479] CR2: 0000000000000068
[ 1255.632756] ---[ end trace 34a69ba0477d036f ]---

Fix this by adding another scsi_target state STARGET_CREATED_REMOVE
to distinguish this case.

Fixes: f05795d3d7 ("scsi: Add intermediate STARGET_REMOVE state to scsi_target_state")
Reported-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-07-01 16:54:44 -04:00
Bart Van Assche 255ee9320e scsi: Make __scsi_remove_device go straight from BLOCKED to DEL
If a device is blocked, make __scsi_remove_device() cause it to
transition to the DEL state. This means that all the commands issued in
.shutdown() will error in the mid-layer, thus making the removal proceed
without being stopped.

This patch is a slightly modified version of a patch from James
Bottomley. This patch avoids that the following lockup occurs:

Call Trace:
 schedule+0x35/0x80
 schedule_timeout+0x237/0x2d0
 io_schedule_timeout+0xa6/0x110
 wait_for_completion_io+0xa3/0x110
 blk_execute_rq+0xdf/0x120
 scsi_execute+0xce/0x150 [scsi_mod]
 scsi_execute_req_flags+0x8f/0xf0 [scsi_mod]
 sd_sync_cache+0xa9/0x190 [sd_mod]
 sd_shutdown+0x6a/0x100 [sd_mod]
 sd_remove+0x64/0xc0 [sd_mod]
 __device_release_driver+0x8d/0x120
 device_release_driver+0x1e/0x30
 bus_remove_device+0xf9/0x170
 device_del+0x127/0x240
 __scsi_remove_device+0xc1/0xd0 [scsi_mod]
 scsi_forget_host+0x57/0x60 [scsi_mod]
 scsi_remove_host+0x72/0x110 [scsi_mod]
 srp_remove_work+0x8b/0x200 [ib_srp]

Reported-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Israel Rukshin <israelr@mellanox.com>
Cc: Max Gurtovoy <maxg@mellanox.com>
Cc: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-12 20:55:59 -04:00
Bart Van Assche 0db6ca8a5e scsi: Protect SCSI device state changes with a mutex
Serializing SCSI device state changes avoids that two state changes can
occur concurrently, e.g. the state changes in scsi_target_block() and
__scsi_remove_device(). This serialization is essential to make patch
"Make __scsi_remove_device go straight from BLOCKED to DEL" work
reliably.

Enable this mechanism for all scsi_target_*block() callers but not for
the scsi_internal_device_unblock() calls from the mpt3sas driver because
that driver can call scsi_internal_device_unblock() from atomic context.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-12 20:55:59 -04:00
Wei Fang d2a145252c scsi: avoid a permanent stop of the scsi device's request queue
A race between scanning and fc_remote_port_delete() may result in a
permanent stop if the device gets blocked before scsi_sysfs_add_sdev()
and unblocked after.  The reason is that blocking a device sets both the
SDEV_BLOCKED state and the QUEUE_FLAG_STOPPED.  However,
scsi_sysfs_add_sdev() unconditionally sets SDEV_RUNNING which causes the
device to be ignored by scsi_target_unblock() and thus never have its
QUEUE_FLAG_STOPPED cleared leading to a device which is apparently
running but has a stopped queue.

We actually have two places where SDEV_RUNNING is set: once in
scsi_add_lun() which respects the blocked flag and once in
scsi_sysfs_add_sdev() which doesn't.  Since the second set is entirely
spurious, simply remove it to fix the problem.

Cc: <stable@vger.kernel.org>
Reported-by: Zengxi Chen <chenzengxi@huawei.com>
Signed-off-by: Wei Fang <fangwei1@huawei.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-12-14 15:51:17 -05:00
Johannes Thumshirn 305c2e71b3 Revert "scsi: fix soft lockup in scsi_remove_target() on module removal"
Now that we've done a more comprehensive fix with the intermediate
target state we can remove the previous hack introduced with commit
90a88d6ef8 ("scsi: fix soft lockup in scsi_remove_target() on module
removal").

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-15 16:53:07 -04:00
Johannes Thumshirn f05795d3d7 scsi: Add intermediate STARGET_REMOVE state to scsi_target_state
Add intermediate STARGET_REMOVE state to scsi_target_state to avoid
running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE
state is only valid in the path from scsi_remove_target() to
scsi_target_destroy() indicating this target is going to be removed.

This re-fixes the problem introduced in commits bc3f02a795 ("[SCSI]
scsi_remove_target: fix softlockup regression on hot remove") and
4099819356 ("scsi: restart list search after unlock in
scsi_remove_target") in a more comprehensive way.

[mkp: Included James' fix for scsi_target_destroy()]

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: 4099819356
Cc: stable@vger.kernel.org
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-15 16:51:53 -04:00
Hannes Reinecke 1d64508810 scsi: disable automatic target scan
On larger installations it is useful to disable automatic LUN scanning,
and only add the required LUNs via udev rules.  This can speed up bootup
dramatically.

This patch introduces a new scan module parameter value 'manual', which
works like 'none', but can be overridden by setting the 'rescan' value
from scsi_scan_target to 'SCSI_SCAN_MANUAL'.  And it updates all
relevant callers to set the 'rescan' value to 'SCSI_SCAN_MANUAL' if
invoked via the 'scan' option in sysfs.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Bart Van Assche d78540dae7 scsi: Declare local symbols static
Avoid that building with W=1 causes gcc to report warnings about symbols
that have not been declared.

Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-29 20:29:55 -04:00
Hannes Reinecke 688875826f scsi_sysfs: Fix typo in is_bin_visible()
The test for the existence vpd_pg83 is inverted.

Fixes: 7e47976bcf ("scsi_sysfs: add 'is_bin_visible' callback")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Laurence Oberman loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-10 20:29:54 -05:00
Hannes Reinecke 4cd2459c06 scsi_sysfs: call 'device_add' after attaching device handler
'device_add' will be evaluating the 'is_visible' callback when creating
the sysfs attributes. As by this time the device handler has not been
attached the 'access_state' attribute will never be visible.

This patch moves the code around so that the device handler is present
by the time 'is_visible' is evaluated to correctly display the
'access_state' attribute.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:21:41 -05:00
Hannes Reinecke 77c9df9644 scsi: Add 'access_state' and 'preferred_path' attribute
Add an 'access_state' field to struct scsi_device and display them in
sysfs as 'access_state' and 'preferred_path' attribute.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:14:37 -05:00
Hannes Reinecke 7e47976bcf scsi_sysfs: add 'is_bin_visible' callback
Add 'is_bin_visible' callback to blank out unsupported vpd pages.

Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:10:03 -05:00
James Bottomley 90a88d6ef8 scsi: fix soft lockup in scsi_remove_target() on module removal
This softlockup is currently happening:

[  444.088002] NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [kworker/1:1:29]
[  444.088002] Modules linked in: lpfc(-) qla2x00tgt(O) qla2xxx_scst(O) scst_vdisk(O) scsi_transport_fc libcrc32c scst(O) dlm configfs nfsd lockd grace nfs_acl auth_rpcgss sunrpc ed
d snd_pcm_oss snd_mixer_oss snd_seq snd_seq_device dm_mod iTCO_wdt snd_hda_codec_realtek snd_hda_codec_generic gpio_ich iTCO_vendor_support ppdev snd_hda_intel snd_hda_codec snd_hda
_core snd_hwdep tg3 snd_pcm snd_timer libphy lpc_ich parport_pc ptp acpi_cpufreq snd pps_core fjes parport i2c_i801 ehci_pci tpm_tis tpm sr_mod cdrom soundcore floppy hwmon sg 8250_
fintek pcspkr i915 drm_kms_helper uhci_hcd ehci_hcd drm fb_sys_fops sysimgblt sysfillrect syscopyarea i2c_algo_bit usbcore button video usb_common fan ata_generic ata_piix libata th
ermal
[  444.088002] CPU: 1 PID: 29 Comm: kworker/1:1 Tainted: G           O    4.4.0-rc5-2.g1e923a3-default #1
[  444.088002] Hardware name: FUJITSU SIEMENS ESPRIMO E           /D2164-A1, BIOS 5.00 R1.10.2164.A1               05/08/2006
[  444.088002] Workqueue: fc_wq_4 fc_rport_final_delete [scsi_transport_fc]
[  444.088002] task: f6266ec0 ti: f6268000 task.ti: f6268000
[  444.088002] EIP: 0060:[<c07e7044>] EFLAGS: 00000286 CPU: 1
[  444.088002] EIP is at _raw_spin_unlock_irqrestore+0x14/0x20
[  444.088002] EAX: 00000286 EBX: f20d3800 ECX: 00000002 EDX: 00000286
[  444.088002] ESI: f50ba800 EDI: f2146848 EBP: f6269ec8 ESP: f6269ec8
[  444.088002]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[  444.088002] CR0: 8005003b CR2: 08f96600 CR3: 363ae000 CR4: 000006d0
[  444.088002] Stack:
[  444.088002]  f6269eec c066b0f7 00000286 f2146848 f50ba808 f50ba800 f50ba800 f2146a90
[  444.088002]  f2146848 f6269f08 f8f0a4ed f3141000 f2146800 f2146a90 f619fa00 00000040
[  444.088002]  f6269f40 c026cb25 00000001 166c6392 00000061 f6757140 f6136340 00000004
[  444.088002] Call Trace:
[  444.088002]  [<c066b0f7>] scsi_remove_target+0x167/0x1c0
[  444.088002]  [<f8f0a4ed>] fc_rport_final_delete+0x9d/0x1e0 [scsi_transport_fc]
[  444.088002]  [<c026cb25>] process_one_work+0x155/0x3e0
[  444.088002]  [<c026cde7>] worker_thread+0x37/0x490
[  444.088002]  [<c027214b>] kthread+0x9b/0xb0
[  444.088002]  [<c07e72c1>] ret_from_kernel_thread+0x21/0x40

What appears to be happening is that something has pinned the target
so it can't go into STARGET_DEL via final release and the loop in
scsi_remove_target spins endlessly until that happens.

The fix for this soft lockup is to not keep looping over a device that
we've called remove on but which hasn't gone into DEL state.  This
patch will retain a simplistic memory of the last target and not keep
looping over it.

Reported-by: Sebastian Herbszt <herbszt@gmx.de>
Tested-by: Sebastian Herbszt <herbszt@gmx.de>
Fixes: 4099819356
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2016-02-11 21:47:32 -08:00
James Bottomley abaee091a1 Merge branch 'jejb-scsi' into misc 2016-01-07 15:51:13 -08:00
James Bottomley be9e2f775f Merge branch 'mkp-fixes' into fixes 2015-12-03 09:32:33 -08:00
Hannes Reinecke 248d4fe95f scsi: export 'wwid' to sysfs
Use scsi_vpd_lun_id() to export the world-wide unique id (wwid) to
sysfs.  Note that this is the 'best' wwid according to the rules in
scsi_vpd_lun_id(), not every possible wwid presented by the drive.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:42:13 -05:00
Hannes Reinecke 221255aee6 scsi: ignore errors from scsi_dh_add_device()
device handler initialisation might fail due to a number of
reasons. But as device_handlers are optional this shouldn't
cause us to disable the device entirely.
So just ignore errors from scsi_dh_add_device().

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:29:46 -05:00
Hannes Reinecke 41f95dd2ef scsi_dh: move 'dh_state' sysfs attribute to generic code
As scsi_dh.c is now always compiled in we should be moving
the 'dh_state' attribute to the generic code.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:29:19 -05:00
Bart Van Assche e619e6cbec Revert "scsi: Fix a bdi reregistration race"
The SCSI sd driver probes SCSI devices asynchronously. The sd_remove()
function, called indirectly by device_del(), waits until asynchronous
probing has finished. Since the block layer queue must only be cleaned
up after probing has finished, device_del() has to be called before
blk_cleanup_queue(). Hence revert commit bf2cf3baa2.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-12-02 11:53:44 -08:00
Hannes Reinecke 09e2b0b146 scsi: rescan VPD attributes
The VPD page information might change, so we need to be able to update
it. This patch implements a VPD page rescan whenever the 'rescan' sysfs
attribute is triggered.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-11-30 11:23:45 -05:00
Vitaly Kuznetsov be821fd8e6 scsi_sysfs: protect against double execution of __scsi_remove_device()
On some host errors storvsc module tries to remove sdev by scheduling a job
which does the following:

   sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
   if (sdev) {
       scsi_remove_device(sdev);
       scsi_device_put(sdev);
   }

While this code seems correct the following crash is observed:

 general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
 RIP: 0010:[<ffffffff81169979>]  [<ffffffff81169979>] bdi_destroy+0x39/0x220
 ...
 [<ffffffff814aecdc>] ? _raw_spin_unlock_irq+0x2c/0x40
 [<ffffffff8127b7db>] blk_cleanup_queue+0x17b/0x270
 [<ffffffffa00b54c4>] __scsi_remove_device+0x54/0xd0 [scsi_mod]
 [<ffffffffa00b556b>] scsi_remove_device+0x2b/0x40 [scsi_mod]
 [<ffffffffa00ec47d>] storvsc_remove_lun+0x3d/0x60 [hv_storvsc]
 [<ffffffff81080791>] process_one_work+0x1b1/0x530
 ...

The problem comes with the fact that many such jobs (for the same device)
are being scheduled simultaneously. While scsi_remove_device() uses
shost->scan_mutex and scsi_device_lookup() will fail for a device in
SDEV_DEL state there is no protection against someone who did
scsi_device_lookup() before we actually entered __scsi_remove_device(). So
the whole scenario looks like that: two callers do simultaneous (or
preemption happens) calls to scsi_device_lookup() ant these calls succeed
for both of them, after that they try doing scsi_remove_device().
shost->scan_mutex only serializes their calls to __scsi_remove_device()
and we end up doing the cleanup path twice.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-11-19 12:15:09 -05:00
Linus Torvalds d83763f4a6 SCSI misc on 20151113
Sorry for the delay in this patch which was mostly caused by getting the
 merger of the mpt2/mpt3sas driver, which was seen as an essential item of
 maintenance work to do before the drivers diverge too much.  Unfortunately,
 this caused a compile failure (detected by linux-next), which then had to be
 fixed up and incubated.  In addition to the mpt2/3sas rework, there are
 updates from pm80xx, lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc
 and ufs plus an assortment of changes including some year 2038 issues, a fix
 for a remove before detach issue in some drivers and a couple of other minor
 issues.
 
 Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull final round of SCSI updates from James Bottomley:
 "Sorry for the delay in this patch which was mostly caused by getting
  the merger of the mpt2/mpt3sas driver, which was seen as an essential
  item of maintenance work to do before the drivers diverge too much.
  Unfortunately, this caused a compile failure (detected by linux-next),
  which then had to be fixed up and incubated.

  In addition to the mpt2/3sas rework, there are updates from pm80xx,
  lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc and ufs plus
  an assortment of changes including some year 2038 issues, a fix for a
  remove before detach issue in some drivers and a couple of other minor
  issues"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (141 commits)
  mpt3sas: fix inline markers on non inline function declarations
  sd: Clear PS bit before Mode Select.
  ibmvscsi: set max_lun to 32
  ibmvscsi: display default value for max_id, max_lun and max_channel.
  mptfusion: don't allow negative bytes in kbuf_alloc_2_sgl()
  scsi: pmcraid: replace struct timeval with ktime_get_real_seconds()
  mvumi: 64bit value for seconds_since1970
  be2iscsi: Fix bogus WARN_ON length check
  scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice
  mpt3sas: Bump mpt3sas driver version to 09.102.00.00
  mpt3sas: Single driver module which supports both SAS 2.0 & SAS 3.0 HBAs
  mpt2sas, mpt3sas: Update the driver versions
  mpt3sas: setpci reset kernel oops fix
  mpt3sas: Added OEM Gen2 PnP ID branding names
  mpt3sas: Refcount fw_events and fix unsafe list usage
  mpt3sas: Refcount sas_device objects and fix unsafe list usage
  mpt3sas: sysfs attribute to report Backup Rail Monitor Status
  mpt3sas: Ported WarpDrive product SSS6200 support
  mpt3sas: fix for driver fails EEH, recovery from injected pci bus error
  mpt3sas: Manage MSI-X vectors according to HBA device type
  ...
2015-11-13 20:35:54 -08:00
James Bottomley febdfbd213 SCSI queue for 4.4.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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Merge tag '4.4-scsi-mkp' into misc

SCSI queue for 4.4.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-11-12 07:06:18 -05:00
Peter Oberparleiter 5cb9b40d61 scsi_sysfs: Fix queue_ramp_up_period return code
Writing a number to /sys/bus/scsi/devices/<sdev>/queue_ramp_up_period
returns the value of that number instead of the number of bytes written.
This behavior can confuse programs expecting POSIX write() semantics.
Fix this by returning the number of bytes written instead.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-11-09 17:40:22 -08:00
Bart Van Assche bf2cf3baa2 scsi: Fix a bdi reregistration race
Unregister and reregister BDI devices in the proper order. This patch
avoids that the following kernel warning can get triggered:

WARNING: CPU: 7 PID: 203 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x68/0x80()
sysfs: cannot create duplicate filename '/devices/virtual/bdi/8:32'
Workqueue: events_unbound async_run_entry_fn
Call Trace:
[<ffffffff814ff5a4>] dump_stack+0x4c/0x65
[<ffffffff810746ba>] warn_slowpath_common+0x8a/0xc0
[<ffffffff81074736>] warn_slowpath_fmt+0x46/0x50
[<ffffffff81237ca8>] sysfs_warn_dup+0x68/0x80
[<ffffffff81237d8e>] sysfs_create_dir_ns+0x7e/0x90
[<ffffffff81291f58>] kobject_add_internal+0xa8/0x320
[<ffffffff812923a0>] kobject_add+0x60/0xb0
[<ffffffff8138c937>] device_add+0x107/0x5e0
[<ffffffff8138d018>] device_create_groups_vargs+0xd8/0x100
[<ffffffff8138d05c>] device_create_vargs+0x1c/0x20
[<ffffffff8117f233>] bdi_register+0x63/0x2a0
[<ffffffff8117f497>] bdi_register_dev+0x27/0x30
[<ffffffff81281549>] add_disk+0x1a9/0x4e0
[<ffffffffa00c5739>] sd_probe_async+0x119/0x1d0 [sd_mod]
[<ffffffff8109a81a>] async_run_entry_fn+0x4a/0x140
[<ffffffff81091078>] process_one_work+0x1d8/0x7c0
[<ffffffff81091774>] worker_thread+0x114/0x460
[<ffffffff81097878>] kthread+0xf8/0x110
[<ffffffff8150801f>] ret_from_fork+0x3f/0x70

See also patch "block: destroy bdi before blockdev is unregistered"
(commit ID 6cd18e711d).

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-11-09 16:34:14 -08:00
Peter Oberparleiter 863e02d0e1 scsi_sysfs: Fix queue_ramp_up_period return code
Writing a number to /sys/bus/scsi/devices/<sdev>/queue_ramp_up_period
returns the value of that number instead of the number of bytes written.
This behavior can confuse programs expecting POSIX write() semantics.
Fix this by returning the number of bytes written instead.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-11-09 12:26:31 -05:00
Johannes Thumshirn 92e6246c8e scsi: Export SCSI Inquiry data to sysfs
Export the RAW SCSI Inquiry to sysfs as binfile. This way the data can be used
by userland without the need to have and ioctl or use the sg_inq tool.

Here is an example of the provided data

linux:~ # hexdump /sys/class/scsi_device/1\:0\:0\:0/device/inquiry
0000000 8005 3205 001f 0000 4551 554d 2020 2020
0000010 4551 554d 4420 4456 522d 4d4f 2020 2020
0000020 2e32 2e33
0000024

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-11-09 11:46:44 -05:00
Christoph Hellwig 4099819356 scsi: restart list search after unlock in scsi_remove_target
When dropping a lock while iterating a list we must restart the search
as other threads could have manipulated the list under us.  Without this
we can get stuck in an endless loop.  This bug was introduced by

commit bc3f02a795
Author: Dan Williams <djbw@fb.com>
Date:   Tue Aug 28 22:12:10 2012 -0700

    [SCSI] scsi_remove_target: fix softlockup regression on hot remove

Which was itself trying to fix a reported soft lockup issue

http://thread.gmane.org/gmane.linux.kernel/1348679

However, we believe even with this revert of the original patch, the soft
lockup problem has been fixed by

commit f2495e228f
Author: James Bottomley <JBottomley@Parallels.com>
Date:   Tue Jan 21 07:01:41 2014 -0800

    [SCSI] dual scan thread bug fix

Thanks go to Dan Williams <dan.j.williams@intel.com> for tracking all this
prior history down.

Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: bc3f02a795
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-11-05 09:24:14 -08:00
Junichi Nomura 23695e41a1 scsi_dh: fix use-after-free when removing scsi device
The commit 1bab0de027 ("dm-mpath, scsi_dh: don't let dm detach device
handlers") removed reference counting of attached scsi device handler.
As a result, handler data is freed immediately via scsi_dh->detach()
in the context of scsi_remove_device() where activation request can be
still in flight.

This patch moves scsi_dh_handler_detach() to sdev releasing function,
scsi_device_dev_release_usercontext(), at that point the device
is already in quiesced state.

Fixes: 1bab0de027 ("dm-mpath, scsi_dh: don't let dm detach device handlers")
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-10-27 11:22:37 +09:00
Christoph Hellwig 086b91d052 scsi_dh: integrate into the core SCSI code
Stop building scsi_dh as a separate module and integrate it fully into the
core SCSI code with explicit callouts at bus scan time.  For now the
callouts are placed at the same point as the old bus notifiers were called,
but in the future we will be able to look at ALUA INQUIRY data earlier on.

Note that this also means that the device handler modules need to be loaded
by the time we scan the bus.  The next patches will add support for
autoloading device handlers at bus scan time to make sure they are always
loaded if they are enabled in the kernel config.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-28 13:14:56 -07:00
Jens Axboe 1278dd6809 scsi: fix host max depth checking for the 'queue_depth' sysfs interface
Commit 1e6f241604 changed the scsi sysfs 'queue_depth' code to
rejects depths higher than the scsi host template setting. But lots
of hosts set this to 1, and update the settings in the scsi host
when the controller/devices probing happens.

This breaks (at least) mpt2sas and mpt3sas runtime setting of queue
depth, returning EINVAL for all settings but '1'. And once it's set to
1, there's no way to go back up.

Cc: stable@vger.kernel.org
Fixes: 1e6f241604 "scsi: don't allow setting of queue_depth bigger than can_queue"
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-07-16 16:09:53 +03:00
Christoph Hellwig efc3c1df5f scsi: remove ->change_queue_type method
Since we got rid of ordered tag support in 2010 the prime use case of
switching on and off ordered tags has been obsolete.  The other function
of enabling/disabling tagging entirely has only been correctly implemented
by the 53c700 driver and isn't generally useful.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-12-04 09:55:45 +01:00
Christoph Hellwig db5ed4dfd5 scsi: drop reason argument from ->change_queue_depth
Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24 14:45:27 +01:00
Christoph Hellwig 1e6f241604 scsi: don't allow setting of queue_depth bigger than can_queue
We won't ever queue more commands than the host allows.  Instead of
letting drivers either reject or ignore this case handle it in
common code.  Note that various driver use internal constant or
variables that are assigned to both shost->can_queue and checked
in ->change_queue_depth - I did remove those checks as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24 14:45:26 +01:00
Christoph Hellwig 609aa22f3b scsi: remove ordered_tags scsi_device field
Remove the ordered_tags field, we haven't been issuing ordered tags based
on it since the big barrier rework in 2010.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-11-12 11:19:40 +01:00
Subhash Jadavani 6fe8c1dbef scsi: balance out autopm get/put calls in scsi_sysfs_add_sdev()
SCSI Well-known logical units generally don't have any scsi driver
associated with it which means no one will call scsi_autopm_put_device()
on these wlun scsi devices and this would result in keeping the
corresponding scsi device always active (hence LLD can't be suspended as
well). Same exact problem can be seen for other scsi device representing
normal logical unit whose driver is yet to be loaded. This patch fixes
the above problem with this approach:

- make the scsi_autopm_put_device call at the end of scsi_sysfs_add_sdev
  to make it balance out the get earlier in the function.
- let drivers do paired get/put calls in their probe methods.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-09-15 16:02:05 -07:00
Alan Stern 50c4e96411 scsi: don't store LUN bits in CDB[1] for USB mass-storage devices
The SCSI specification requires that the second Command Data Byte
should contain the LUN value in its high-order bits if the recipient
device reports SCSI level 2 or below.  Nevertheless, some USB
mass-storage devices use those bits for other purposes in
vendor-specific commands.  Currently Linux has no way to send such
commands, because the SCSI stack always overwrites the LUN bits.

Testing shows that Windows 7 and XP do not store the LUN bits in the
CDB when sending commands to a USB device.  This doesn't matter if the
device uses the Bulk-Only or UAS transports (which virtually all
modern USB mass-storage devices do), as these have a separate
mechanism for sending the LUN value.

Therefore this patch introduces a flag in the Scsi_Host structure to
inform the SCSI midlayer that a transport does not require the LUN
bits to be stored in the CDB, and it makes usb-storage set this flag
for all devices using the Bulk-Only transport.  (UAS is handled by a
separate driver, but it doesn't really matter because no SCSI-2 or
lower device is at all likely to use UAS.)

The patch also cleans up the code responsible for storing the LUN
value by adding a bitflag to the scsi_device structure.  The test for
whether to stick the LUN value in the CDB can be made when the device
is probed, and stored for future use rather than being made over and
over in the fast path.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Tiziano Bacocco <tiziano.bacocco@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-09-15 16:01:58 -07:00
Daniel Walter f7c65af513 drivers/scsi: replace strict_strto calls
Replace obsolete strict_strto with more appropriate kstrto calls

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:28 -07:00
Christoph Hellwig d285203cf6 scsi: add support for a blk-mq based I/O path.
This patch adds support for an alternate I/O path in the scsi midlayer
which uses the blk-mq infrastructure instead of the legacy request code.

Use of blk-mq is fully transparent to drivers, although for now a host
template field is provided to opt out of blk-mq usage in case any unforseen
incompatibilities arise.

In general replacing the legacy request code with blk-mq is a simple and
mostly mechanical transformation.  The biggest exception is the new code
that deals with the fact the I/O submissions in blk-mq must happen from
process context, which slightly complicates the I/O completion handler.
The second biggest differences is that blk-mq is build around the concept
of preallocated requests that also include driver specific data, which
in SCSI context means the scsi_cmnd structure.  This completely avoids
dynamic memory allocations for the fast path through I/O submission.

Due the preallocated requests the MQ code path exclusively uses the
host-wide shared tag allocator instead of a per-LUN one.  This only
affects drivers actually using the block layer provided tag allocator
instead of their own.  Unlike the old path blk-mq always provides a tag,
although drivers don't have to use it.

For now the blk-mq path is disable by defauly and must be enabled using
the "use_blk_mq" module parameter.  Once the remaining work in the block
layer to make blk-mq more suitable for slow devices is complete I hope
to make it the default and eventually even remove the old code path.

Based on the earlier scsi-mq prototype by Nicholas Bellinger.

Thanks to Bart Van Assche and Robert Elliot for testing, benchmarking and
various sugestions and code contributions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 17:16:28 -04:00
Christoph Hellwig cd9070c9c5 scsi: fix the {host,target,device}_blocked counter mess
Seems like these counters are missing any sort of synchronization for
updates, as a over 10 year old comment from me noted.  Fix this by
using atomic counters, and while we're at it also make sure they are
in the same cacheline as the _busy counters and not needlessly stored
to in every I/O completion.

With the new model the _busy counters can temporarily go negative,
so all the readers are updated to check for > 0 values.  Longer
term every successful I/O completion will reset the counters to zero,
so the temporarily negative values will not cause any harm.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 17:15:48 -04:00
Christoph Hellwig 71e75c97f9 scsi: convert device_busy to atomic_t
Avoid taking the queue_lock to check the per-device queue limit.  Instead
we do an atomic_inc_return early on to grab our slot in the queue,
and if necessary decrement it after finishing all checks.

Unlike the host and target busy counters this doesn't allow us to avoid the
queue_lock in the request_fn due to the way the interface works, but it'll
allow us to prepare for using the blk-mq code, which doesn't use the
queue_lock at all, and it at least avoids a queue_lock round trip in
scsi_device_unbusy, which is still important given how busy the queue_lock
is.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 07:43:45 -04:00
Christoph Hellwig 7466501608 scsi: convert host_busy to atomic_t
Avoid taking the host-wide host_lock to check the per-host queue limit.
Instead we do an atomic_inc_return early on to grab our slot in the queue,
and if necessary decrement it after finishing all checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 07:43:43 -04:00
Hannes Reinecke 9cb78c16f5 scsi: use 64-bit LUNs
The SCSI standard defines 64-bit values for LUNs, and large arrays
employing large or hierarchical LUN numbers become more and more
common.

So update the linux SCSI stack to use 64-bit LUN numbers.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:37 +02:00
Linus Torvalds 1a0b6abaea SCSI misc on 20140401
This patch consists of the usual driver updates (megaraid_sas, scsi_debug,
 qla2xxx, qla4xxx, lpfc, bnx2fc, be2iscsi, hpsa, ipr) plus an assortment of
 minor fixes and the first precursors of SCSI-MQ (the code path
 simplifications) and the bug fix for the USB oops on remove (which involves an
 infrastructure change, so is sent via the main tree with a delayed backport
 after a cycle in which it is shown to introduce no new bugs).
 
 Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull first round of SCSI updates from James Bottomley:
 "This patch consists of the usual driver updates (megaraid_sas,
  scsi_debug, qla2xxx, qla4xxx, lpfc, bnx2fc, be2iscsi, hpsa, ipr) plus
  an assortment of minor fixes and the first precursors of SCSI-MQ (the
  code path simplifications) and the bug fix for the USB oops on remove
  (which involves an infrastructure change, so is sent via the main tree
  with a delayed backport after a cycle in which it is shown to
  introduce no new bugs)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (196 commits)
  [SCSI] sd: Quiesce mode sense error messages
  [SCSI] add support for per-host cmd pools
  [SCSI] simplify command allocation and freeing a bit
  [SCSI] megaraid: simplify internal command handling
  [SCSI] ses: Use vpd information from scsi_device
  [SCSI] Add EVPD page 0x83 and 0x80 to sysfs
  [SCSI] Return VPD page length in scsi_vpd_inquiry()
  [SCSI] scsi_sysfs: Implement 'is_visible' callback
  [SCSI] hpsa: update driver version to 3.4.4-1
  [SCSI] hpsa: fix bad endif placement in RAID 5 mapper code
  [SCSI] qla2xxx: Fix build errors related to invalid print fields on some architectures.
  [SCSI] bfa: Replace large udelay() with mdelay()
  [SCSI] vmw_pvscsi: Some improvements in pvscsi driver.
  [SCSI] vmw_pvscsi: Add support for I/O requests coalescing.
  [SCSI] vmw_pvscsi: Fix pvscsi_abort() function.
  [SCSI] remove deprecated IRQF_DISABLED from SCSI
  [SCSI] bfa: Updating Maintainers email ids
  [SCSI] ipr: Add new CCIN definition for Grand Canyon support
  [SCSI] ipr: Format HCAM overlay ID 0x21
  [SCSI] ipr: Use pci_enable_msi_range() and pci_enable_msix_range()
  ...
2014-04-01 18:49:04 -07:00
Hannes Reinecke b3ae8780b4 [SCSI] Add EVPD page 0x83 and 0x80 to sysfs
EVPD page 0x83 is used to uniquely identify the device.
So instead of having each and every program issue a separate
SG_IO call to retrieve this information it does make far more
sense to display it in sysfs.

Some older devices (most notably tapes) will only report reliable
information in page 0x80 (Unit Serial Number). So export this
in the sysfs attribute 'vpd_pg80'.

[jejb: checkpatch fix]
[hare: attach after transport configure]
[fengguang.wu@intel.com: spotted problems with the original now fixed]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-27 08:25:33 -07:00