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60 Commits

Author SHA1 Message Date
Eric Farman 773c7220e2 scsi: virtio_scsi: Reject commands when virtqueue is broken
In the case of a graceful set of detaches, where the virtio-scsi-ccw
disk is removed from the guest prior to the controller, the guest
behaves quite normally.  Specifically, the detach gets us into
sd_sync_cache to issue a Synchronize Cache(10) command, which
immediately fails (and is retried a couple of times) because the device
has been removed.  Later, the removal of the controller sees two CRWs
presented, but there's no further indication of the removal from the
guest viewpoint.

 [   17.217458] sd 0:0:0:0: [sda] Synchronizing SCSI cache
 [   17.219257] sd 0:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK
 [   21.449400] crw_info : CRW reports slct=0, oflw=0, chn=1, rsc=3, anc=0, erc=4, rsid=2
 [   21.449406] crw_info : CRW reports slct=0, oflw=0, chn=0, rsc=3, anc=0, erc=4, rsid=0

However, on s390, the SCSI disks can be removed "by surprise" when an
entire controller (host) is removed and all associated disks are removed
via the loop in scsi_forget_host.  The same call to sd_sync_cache is
made, but because the controller has already been removed, the
Synchronize Cache(10) command is neither issued (and then failed) nor
rejected.

That the I/O isn't returned means the guest cannot have other devices
added nor removed, and other tasks (such as shutdown or reboot) issued
by the guest will not complete either.  The virtio ring has already been
marked as broken (via virtio_break_device in virtio_ccw_remove), but we
still attempt to queue the command only to have it remain there.  The
calling sequence provides a bit of distinction for us:

  virtscsi_queuecommand()
   -> virtscsi_kick_cmd()
    -> virtscsi_add_cmd()
     -> virtqueue_add_sgs()
      -> virtqueue_add()
         if success
           return 0
         elseif vq->broken or vring_mapping_error()
           return -EIO
         else
           return -ENOSPC

A return of ENOSPC is generally a temporary condition, so returning
"host busy" from virtscsi_queuecommand makes sense here, to have it
redriven in a moment or two.  But the EIO return code is more of a
permanent error and so it would be wise to return the I/O itself and
allow the calling thread to finish gracefully.  The result is these four
kernel messages in the guest (the fourth one does not occur prior to
this patch):

 [   22.921562] crw_info : CRW reports slct=0, oflw=0, chn=1, rsc=3, anc=0, erc=4, rsid=2
 [   22.921580] crw_info : CRW reports slct=0, oflw=0, chn=0, rsc=3, anc=0, erc=4, rsid=0
 [   22.921978] sd 0:0:0:0: [sda] Synchronizing SCSI cache
 [   22.921993] sd 0:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK

I opted to fill in the same response data that is returned from the more
graceful device detach, where the disk device is removed prior to the
controller device.

Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-20 19:17:18 -05:00
Linus Torvalds 4dfddf5036 SCSI misc on 20161006
This update includes the usual round of major driver updates (hpsa, be2iscsi,
 hisi_sas, zfcp, cxlflash).  There's a new incarnation of hpsa called smartpqi
 for which a driver is added, there's some cleanup work of the ibm vscsi target
 and updates to libfc, plus a whole host of minor fixes and updates and finally
 the removal of several ISA drivers which seem not to have been used for years.
 
 Signed-off-by: James Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This update includes the usual round of major driver updates (hpsa,
  be2iscsi, hisi_sas, zfcp, cxlflash). There's a new incarnation of hpsa
  called smartpqi for which a driver is added, there's some cleanup work
  of the ibm vscsi target and updates to libfc, plus a whole host of
  minor fixes and updates and finally the removal of several ISA drivers
  which seem not to have been used for years"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (173 commits)
  scsi: mvsas: Mark symbols static where possible
  scsi: pm8001: Mark symbols static where possible
  scsi: arcmsr: Simplify user_len checking
  scsi: fcoe: fix off by one in eth2fc_speed()
  scsi: dtc: remove from tree
  scsi: t128: remove from tree
  scsi: pas16: remove from tree
  scsi: u14-34f: remove from tree
  scsi: ultrastor: remove from tree
  scsi: in2000: remove from tree
  scsi: wd7000: remove from tree
  scsi: scsi_dh_alua: Fix memory leak in alua_rtpg()
  scsi: lpfc: Mark symbols static where possible
  scsi: hpsa: correct call to hpsa_do_reset
  scsi: ufs: Get a TM service response from the correct offset
  scsi: ibmvfc: Fix I/O hang when port is not mapped
  scsi: megaraid_sas: clean function declarations in megaraid_sas_base.c up
  scsi: ipr: Remove redundant messages at adapter init time
  scsi: ipr: Don't log unnecessary 9084 error details
  scsi: smartpqi: raid bypass lba calculation fix
  ...
2016-10-07 09:28:53 -07:00
Sebastian Andrzej Siewior 8904f5a5af virtio scsi: Convert to hotplug state machine
Install the callbacks via the state machine. It uses the multi instance
infrastructure of the hotplug code to handle each interface.

virtscsi_set_affinity() is removed from virtscsi_init() because
virtscsi_cpu_notif_add() (the function which registers the instance) is invoked
right after it and the cpuhp_state_add_instance() functions invokes the startup
callback on all online CPUs.

The same thing can not be applied virtscsi_cpu_notif_remove() because
virtscsi_remove_vqs() invokes virtscsi_set_affinity() with affinity = false as
argument but the old CPU_DEAD state invoked the function with affinity = true
(which does not match the DEAD callback).

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: linux-scsi@vger.kernel.org
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: virtualization@lists.linux-foundation.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160906170457.32393-11-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-19 21:44:29 +02:00
Daniel Wagner e8f8142025 scsi: virtio_scsi: Use complete() instead complete_all()
There is only one waiter for the completion, therefore there is no need
to use complete_all(). Let's make that clear by using complete() instead
of complete_all().

The usage pattern of the completion is:

waiter context                          waker context

virtscsi_tmf()
  DECLARE_COMPLETION_ONSTACK()
  virtscsi_kick_cmd()
  wait_for_completion()

                                        virtscsi_complete_free()
                                          complete()

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-14 13:19:57 -04:00
Linus Torvalds d1a343a023 virtio/vhost: fixes for 4.2
Bugfixes and documentation fixes. Igor's patch that allows
 users to tweak memory table size is borderline,
 but it does fix known crashes, so I merged it.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost fixes from Michael Tsirkin:
 "Bugfixes and documentation fixes.

  Igor's patch that allows users to tweak memory table size is
  borderline, but it does fix known crashes, so I merged it"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: add max_mem_regions module parameter
  vhost: extend memory regions allocation to vmalloc
  9p/trans_virtio: reset virtio device on remove
  virtio/s390: rename drivers/s390/kvm -> drivers/s390/virtio
  MAINTAINERS: separate section for s390 virtio drivers
  virtio: define virtio_pci_cfg_cap in header.
  virtio: Fix typecast of pointer in vring_init()
  virtio scsi: fix unused variable warning
  vhost: use binary search instead of linear in find_region()
  virtio_net: document VIRTIO_NET_CTRL_GUEST_OFFLOADS
2015-07-23 13:07:04 -07:00
Stephen Rothwell 908a5544cd virtio scsi: fix unused variable warning
drivers/scsi/virtio_scsi.c: In function 'virtscsi_probe':
drivers/scsi/virtio_scsi.c:952:11: warning: unused variable 'host_prot' [-Wunused-variable]
  int err, host_prot;
           ^

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07 14:27:03 +03:00
Christoph Hellwig c5c2567fd3 virtio_scsi: don't select CONFIG_BLK_DEV_INTEGRITY
T10 PI is just another optional feature, LLDDs should work without
the infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-05-25 09:14:47 -07:00
Michael S. Tsirkin 8cab3cd6ad virtio/scsi: verify device has config space
Some devices might not implement config space access
(e.g. remoteproc used not to - before 3.9).
virtio/scsi needs config space access so make it
fail gracefully if not there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:47 +10:30
Linus Torvalds 6b9e2cea42 virtio: virtio 1.0 support, misc patches
This adds a lot of infrastructure for virtio 1.0 support.
 Notable missing pieces: virtio pci, virtio balloon (needs spec extension),
 vhost scsi.
 
 Plus, there are some minor fixes in a couple of places.
 
 Cc: David Miller <davem@davemloft.net>
 Cc: Rusty Russell <rusty@rustcorp.com.au>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "virtio: virtio 1.0 support, misc patches

  This adds a lot of infrastructure for virtio 1.0 support.  Notable
  missing pieces: virtio pci, virtio balloon (needs spec extension),
  vhost scsi.

  Plus, there are some minor fixes in a couple of places.

  Note: some net drivers are affected by these patches.  David said he's
  fine with merging these patches through my tree.

  Rusty's on vacation, he acked using my tree for these, too"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (70 commits)
  virtio_ccw: finalize_features error handling
  virtio_ccw: future-proof finalize_features
  virtio_pci: rename virtio_pci -> virtio_pci_common
  virtio_pci: update file descriptions and copyright
  virtio_pci: split out legacy device support
  virtio_pci: setup config vector indirectly
  virtio_pci: setup vqs indirectly
  virtio_pci: delete vqs indirectly
  virtio_pci: use priv for vq notification
  virtio_pci: free up vq->priv
  virtio_pci: fix coding style for structs
  virtio_pci: add isr field
  virtio: drop legacy_only driver flag
  virtio_balloon: drop legacy_only driver flag
  virtio_ccw: rev 1 devices set VIRTIO_F_VERSION_1
  virtio: allow finalize_features to fail
  virtio_ccw: legacy: don't negotiate rev 1/features
  virtio: add API to detect legacy devices
  virtio_console: fix sparse warnings
  vhost: remove unnecessary forward declarations in vhost.h
  ...
2014-12-11 12:20:31 -08:00
Michael S. Tsirkin 51cdc3815f virtio: drop VIRTIO_F_VERSION_1 from drivers
Core activates this bit automatically now,
drop it from drivers that set it explicitly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:06:32 +02:00
Michael S. Tsirkin d75dff39df virtio_scsi: v1.0 support
Note: for consistency, and to avoid sparse errors,
  convert all fields, even those no longer in use
  for virtio v1.0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-09 12:05:31 +02:00
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 c40ecc12cf scsi: avoid ->change_queue_depth indirection for queue full tracking
All drivers use the implementation for ramping the queue up and down, so
instead of overloading the change_queue_depth method call the
implementation diretly if the driver opts into it by setting the
track_queue_depth flag in the host template.

Note that a few drivers validated the new queue depth in their
change_queue_depth method, but as we never go over the queue depth
set during slave_configure or the sysfs file this isn't nessecary
and can safely be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>
2014-11-24 14:45:12 +01:00
Ming Lei ccbedf117f virtio_scsi: support multi hw queue of blk-mq
Since virtio_scsi has supported multi virtqueue already,
it is natural to map the virtque to hw-queue of blk-mq.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:28 +01:00
Christoph Hellwig c8b09f6fb6 scsi: don't set tagging state from scsi_adjust_queue_depth
Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth.  For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.

Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway.  The one other case looks
broken, but I've kept the behavior as-is for now.

Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.

Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-11-12 11:19:43 +01:00
Michael S. Tsirkin 5d8f16d08b virtio_scsi: drop scan callback
Enable VQs early like we do for restore.
This makes it possible to drop the scan callback,
moving scanning into the probe function, and making
code simpler.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-15 10:25:14 +10:30
Michael S. Tsirkin e67423c7b4 virtio_scsi: fix race on device removal
We cancel event work on device removal, but an interrupt
could trigger immediately after this, and queue it
again.

To fix, set a flag.

Loosely based on patch by Paolo Bonzini

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-15 10:25:12 +10:30
Paolo Bonzini 1fa5b2a784 virito_scsi: use freezable WQ for events
Michael S. Tsirkin noticed a race condition:
we reset device on freeze, but system WQ is still
running so it might try adding bufs to a VQ meanwhile.

To fix, switch to handling events from the freezable WQ.

Reported-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-15 10:25:11 +10:30
Michael S. Tsirkin 52c9cf1ac3 virtio_scsi: enable VQs early on restore
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after restore returns, virtio scsi violated
this rule on restore by kicking event vq within restore.

To fix, call virtio_device_ready before using event queue.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-15 10:25:08 +10:30
Michael S. Tsirkin cd67904895 virtio_scsi: move kick event out from virtscsi_init
We currently kick event within virtscsi_init,
before host is fully initialized.

This can in theory confuse guest if device
consumes the buffers immediately.

To fix,  move virtscsi_kick_event_all out to scan/restore.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-15 10:25:06 +10:30
Venkatesh Srinivas 761f1193f2 virtio-scsi: Implement change_queue_depth for virtscsi targets
change_queue_depth allows changing per-target queue depth via sysfs.

It also allows the SCSI midlayer to ramp down the number of concurrent
inflight requests in response to a SCSI BUSY status response and allows
the midlayer to ramp the count back up to the device maximum when the
BUSY condition has resolved.

Signed-off-by: Venkatesh Srinivas <venkateshs@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25 17:17:00 -04:00
Ming Lei 938ece711c virtio-scsi: replace target spinlock with seqcount
The spinlock of tgt_lock is only for serializing read and write
req_vq, one lockless seqcount is enough for the purpose.

On one 16core VM with vhost-scsi backend, the patch can improve
IOPS with 3% on random read test.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
[Add initialization in virtscsi_target_alloc. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25 17:17:00 -04:00
Paolo Bonzini 8faeb529b2 virtio-scsi: fix various bad behavior on aborted requests
Even though the virtio-scsi spec guarantees that all requests related
to the TMF will have been completed by the time the TMF itself completes,
the request queue's callback might not have run yet.  This causes requests
to be completed more than once, and as a result triggers a variety of
BUGs or oopses.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-25 13:29:33 +02:00
Paolo Bonzini cdda0e5acb virtio-scsi: avoid cancelling uninitialized work items
Calling the workqueue interface on uninitialized work items isn't a
good idea even if they're zeroed. It's not failing catastrophically only
through happy accidents.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-25 13:29:33 +02:00
Linus Torvalds ed9ea4ed3a Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "The highlights this round include:

   - Add support for T10 PI pass-through between vhost-scsi +
     virtio-scsi (MST + Paolo + MKP + nab)
   - Add support for T10 PI in qla2xxx target mode (Quinn + MKP + hch +
     nab, merged through scsi.git)
   - Add support for percpu-ida pre-allocation in qla2xxx target code
     (Quinn + nab)
   - A number of iser-target fixes related to hardening the network
     portal shutdown path (Sagi + Slava)
   - Fix response length residual handling for a number of control CDBs
     (Roland + Christophe V.)
   - Various iscsi RFC conformance fixes in the CHAP authentication path
     (Tejas and Calsoft folks + nab)
   - Return TASK_SET_FULL status for tcm_fc(FCoE) DataIn + Response
     failures (Vasu + Jun + nab)
   - Fix long-standing ABORT_TASK + session reset hang (nab)
   - Convert iser-initiator + iser-target to include T10 bytes into EDTL
     (Sagi + Or + MKP + Mike Christie)
   - Fix NULL pointer dereference regression related to XCOPY introduced
     in v3.15 + CC'ed to v3.12.y (nab)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (34 commits)
  target: Fix NULL pointer dereference for XCOPY in target_put_sess_cmd
  vhost-scsi: Include prot_bytes into expected data transfer length
  TARGET/sbc,loopback: Adjust command data length in case pi exists on the wire
  libiscsi, iser: Adjust data_length to include protection information
  scsi_cmnd: Introduce scsi_transfer_length helper
  target: Report correct response length for some commands
  target/sbc: Check that the LBA and number of blocks are correct in VERIFY
  target/sbc: Remove sbc_check_valid_sectors()
  Target/iscsi: Fix sendtargets response pdu for iser transport
  Target/iser: Fix a wrong dereference in case discovery session is over iser
  iscsi-target: Fix ABORT_TASK + connection reset iscsi_queue_req memory leak
  target: Use complete_all for se_cmd->t_transport_stop_comp
  target: Set CMD_T_ACTIVE bit for Task Management Requests
  target: cleanup some boolean tests
  target/spc: Simplify INQUIRY EVPD=0x80
  tcm_fc: Generate TASK_SET_FULL status for response failures
  tcm_fc: Generate TASK_SET_FULL status for DataIN failures
  iscsi-target: Reject mutual authentication with reflected CHAP_C
  iscsi-target: Remove no-op from iscsit_tpg_del_portal_group
  iscsi-target: Fix CHAP_A parameter list handling
  ...
2014-06-12 22:38:32 -07:00
Linus Torvalds 5c02c392cd Main excitement is a virtio_scsi fix for alloc holding spinlock on the abort
path, which I refuse to CC stable since (1) I discovered it myself, and
 (2) it's been there forever with no reports.
 
 Cheers,
 Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "Main excitement is a virtio_scsi fix for alloc holding spinlock on the
  abort path, which I refuse to CC stable since (1) I discovered it
  myself, and (2) it's been there forever with no reports"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_scsi: don't call virtqueue_add_sgs(... GFP_NOIO) holding spinlock.
  virtio-rng: fixes for device registration/unregistration
  virtio-rng: fix boot with virtio-rng device
  virtio-rng: support multiple virtio-rng devices
  virtio_ccw: introduce device_lost in virtio_ccw_device
  virtio: virtio_break_device() to mark all virtqueues broken.
2014-06-11 21:10:33 -07:00
Nicholas Bellinger e6dc783a38 virtio-scsi: Enable DIF/DIX modes in SCSI host LLD
This patch updates virtscsi_probe() to setup necessary Scsi_Host
level protection resources. (currently hardcoded to 1)

It changes virtscsi_add_cmd() to attach outgoing / incoming
protection SGLs preceeding the data payload, and is using the
new virtio_scsi_cmd_req_pi->pi_bytes[out,in] field to signal
to signal to vhost/scsi bytes to expect for protection data.

(Add missing #include <linux/blkdev.h> for blk_integrity - sfr + nab)

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@dev.mellanox.co.il>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-06-02 12:42:19 -07:00
Rusty Russell c77fba9ab0 virtio_scsi: don't call virtqueue_add_sgs(... GFP_NOIO) holding spinlock.
This triggers every time we do a SCSI abort:

virtscsi_tmf -> virtscsi_kick_cmd (grab lock and call) -> virtscsi_add_cmd
	-> virtqueue_add_sgs (GFP_NOIO)

Logs look like this:
 sd 0:0:0:0: [sda] abort
 BUG: sleeping function called from invalid context at mm/slub.c:966
 in_atomic(): 1, irqs_disabled(): 1, pid: 6, name: kworker/u2:0
 3 locks held by kworker/u2:0/6:
  #0:  ("scsi_tmf_%d"shost->host_no){......}, at: [<c0153180>] process_one_work+0xe0/0x3d0
  #1:  ((&(&cmd->abort_work)->work)){......}, at: [<c0153180>] process_one_work+0xe0/0x3d0
  #2:  (&(&virtscsi_vq->vq_lock)->rlock){......}, at: [<c043f508>] virtscsi_kick_cmd+0x18/0x1b0
 CPU: 0 PID: 6 Comm: kworker/u2:0 Not tainted 3.15.0-rc5+ #110
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-rc1-0-gb1d4dc9-20140515_140003-nilsson.home.kraxel.org 04/01/2014
 Workqueue: scsi_tmf_0 scmd_eh_abort_handler

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2014-05-21 11:25:41 +09:30
Christoph Hellwig b54197c43d virtio_scsi: use cmd_size
Taken almost entirely from Nicholas Bellinger's scsi-mq conversion.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-05-19 19:57:23 +02:00
Ming Lei f259d9bdd2 virtio_scsi: remove ACCESS_ONCE() and smp_read_barrier_depends()
Access to tgt->req_vq is strictly serialized by spin_lock
of tgt->tgt_lock, so the ACCESS_ONCE() isn't necessary.

smp_read_barrier_depends() in virtscsi_req_done was introduced
to order reading req_vq and decreasing tgt->reqs, but it isn't
needed now because req_vq is read from
scsi->req_vqs[vq->index - VIRTIO_SCSI_VQ_BASE] instead of
tgt->req_vq, so remove the unnecessary barrier.

Also remove related comment about the barrier.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-05-19 19:12:26 +02:00
Fam Zheng 0c8482ac92 [SCSI] virtio-scsi: Skip setting affinity on uninitialized vq
virtscsi_init calls virtscsi_remove_vqs on err, even before initializing
the vqs. The latter calls virtscsi_set_affinity, so let's check the
pointer there before setting affinity on it.

This fixes a panic when setting device's num_queues=2 on RHEL 6.5:

qemu-system-x86_64 ... \
-device virtio-scsi-pci,id=scsi0,addr=0x13,...,num_queues=2 \
-drive file=/stor/vm/dummy.raw,id=drive-scsi-disk,... \
-device scsi-hd,drive=drive-scsi-disk,...

[    0.354734] scsi0 : Virtio SCSI HBA
[    0.379504] BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
[    0.380141] IP: [<ffffffff814741ef>] __virtscsi_set_affinity+0x4f/0x120
[    0.380141] PGD 0
[    0.380141] Oops: 0000 [#1] SMP
[    0.380141] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.0+ #5
[    0.380141] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007
[    0.380141] task: ffff88003c9f0000 ti: ffff88003c9f8000 task.ti: ffff88003c9f8000
[    0.380141] RIP: 0010:[<ffffffff814741ef>]  [<ffffffff814741ef>] __virtscsi_set_affinity+0x4f/0x120
[    0.380141] RSP: 0000:ffff88003c9f9c08  EFLAGS: 00010256
[    0.380141] RAX: 0000000000000000 RBX: ffff88003c3a9d40 RCX: 0000000000001070
[    0.380141] RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
[    0.380141] RBP: ffff88003c9f9c28 R08: 00000000000136c0 R09: ffff88003c801c00
[    0.380141] R10: ffffffff81475229 R11: 0000000000000008 R12: 0000000000000000
[    0.380141] R13: ffffffff81cc7ca8 R14: ffff88003cac3d40 R15: ffff88003cac37a0
[    0.380141] FS:  0000000000000000(0000) GS:ffff88003e400000(0000) knlGS:0000000000000000
[    0.380141] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    0.380141] CR2: 0000000000000020 CR3: 0000000001c0e000 CR4: 00000000000006f0
[    0.380141] Stack:
[    0.380141]  ffff88003c3a9d40 0000000000000000 ffff88003cac3d80 ffff88003cac3d40
[    0.380141]  ffff88003c9f9c48 ffffffff814742e8 ffff88003c26d000 ffff88003c26d000
[    0.380141]  ffff88003c9f9c68 ffffffff81474321 ffff88003c26d000 ffff88003c3a9d40
[    0.380141] Call Trace:
[    0.380141]  [<ffffffff814742e8>] virtscsi_set_affinity+0x28/0x40
[    0.380141]  [<ffffffff81474321>] virtscsi_remove_vqs+0x21/0x50
[    0.380141]  [<ffffffff81475231>] virtscsi_init+0x91/0x240
[    0.380141]  [<ffffffff81365290>] ? vp_get+0x50/0x70
[    0.380141]  [<ffffffff81475544>] virtscsi_probe+0xf4/0x280
[    0.380141]  [<ffffffff81363ea5>] virtio_dev_probe+0xe5/0x140
[    0.380141]  [<ffffffff8144c669>] driver_probe_device+0x89/0x230
[    0.380141]  [<ffffffff8144c8ab>] __driver_attach+0x9b/0xa0
[    0.380141]  [<ffffffff8144c810>] ? driver_probe_device+0x230/0x230
[    0.380141]  [<ffffffff8144c810>] ? driver_probe_device+0x230/0x230
[    0.380141]  [<ffffffff8144ac1c>] bus_for_each_dev+0x8c/0xb0
[    0.380141]  [<ffffffff8144c499>] driver_attach+0x19/0x20
[    0.380141]  [<ffffffff8144bf28>] bus_add_driver+0x198/0x220
[    0.380141]  [<ffffffff8144ce9f>] driver_register+0x5f/0xf0
[    0.380141]  [<ffffffff81d27c91>] ? spi_transport_init+0x79/0x79
[    0.380141]  [<ffffffff8136403b>] register_virtio_driver+0x1b/0x30
[    0.380141]  [<ffffffff81d27d19>] init+0x88/0xd6
[    0.380141]  [<ffffffff81d27c18>] ? scsi_init_procfs+0x5b/0x5b
[    0.380141]  [<ffffffff81ce88a7>] do_one_initcall+0x7f/0x10a
[    0.380141]  [<ffffffff81ce8aa7>] kernel_init_freeable+0x14a/0x1de
[    0.380141]  [<ffffffff81ce8b3b>] ? kernel_init_freeable+0x1de/0x1de
[    0.380141]  [<ffffffff817dec20>] ? rest_init+0x80/0x80
[    0.380141]  [<ffffffff817dec29>] kernel_init+0x9/0xf0
[    0.380141]  [<ffffffff817e68fc>] ret_from_fork+0x7c/0xb0
[    0.380141]  [<ffffffff817dec20>] ? rest_init+0x80/0x80
[    0.380141] RIP  [<ffffffff814741ef>] __virtscsi_set_affinity+0x4f/0x120
[    0.380141]  RSP <ffff88003c9f9c08>
[    0.380141] CR2: 0000000000000020
[    0.380141] ---[ end trace 8074b70c3d5e1d73 ]---
[    0.475018] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009
[    0.475018]
[    0.475068] Kernel Offset: 0x0 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffff9fffffff)
[    0.475068] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009

[jejb: checkpatch fixes]
Signed-off-by: Fam Zheng <famz@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-04-28 16:16:08 -07:00
Asias He f466f75385 virtio-scsi: Fix hotcpu_notifier use-after-free with virtscsi_freeze
vqs are freed in virtscsi_freeze but the hotcpu_notifier is not
unregistered. We will have a use-after-free usage when the notifier
callback is called after virtscsi_freeze.

Fixes: 285e71ea6f
("virtio-scsi: reset virtqueue affinity when doing cpu hotplug")

Cc: stable@vger.kernel.org
Signed-off-by: Asias He <asias.hejun@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-01-16 10:22:27 +10:30
Heinz Graalfs 2bf4fd3139 virtio_scsi: verify if queue is broken after virtqueue_get_buf()
If virtqueue_get_buf() returned with a NULL pointer avoid a possibly
endless loop by checking for a broken virtqueue.

Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-11-11 11:53:26 +10:30
Rusty Russell 855e0c5288 virtio: use size-based config accessors.
This lets the transport do endian conversion if necessary, and insulates
the drivers from the difference.

Most drivers can use the simple helpers virtio_cread() and virtio_cwrite().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-10-17 10:55:37 +10:30
Aaron Lu 8910700039 virtio: pm: use CONFIG_PM_SLEEP instead of CONFIG_PM
The freeze and restore functions defined in virtio drivers are used
for suspend and hibernate, so CONFIG_PM_SLEEP is more appropriate than
CONFIG_PM. This patch replace all CONFIG_PM with CONFIG_PM_SLEEP for
virtio drivers that implement freeze and restore callbacks.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-09-23 15:45:58 +09:30
Asias He aa52aeea27 virtio-scsi: Fix virtqueue affinity setup
vscsi->num_queues counts the number of request virtqueue which does not
include the control and event virtqueue. It is wrong to subtract
VIRTIO_SCSI_VQ_BASE from vscsi->num_queues.

This patch fixes the following panic.

(qemu) device_del scsi0

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
 IP: [<ffffffff8179b29f>] __virtscsi_set_affinity+0x6f/0x120
 PGD 0
 Oops: 0000 [#1] SMP
 Modules linked in:
 CPU: 0 PID: 659 Comm: kworker/0:1 Not tainted 3.11.0-rc2+ #1172
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 Workqueue: kacpi_hotplug _handle_hotplug_event_func
 task: ffff88007bee1cc0 ti: ffff88007bfe4000 task.ti: ffff88007bfe4000
 RIP: 0010:[<ffffffff8179b29f>]  [<ffffffff8179b29f>] __virtscsi_set_affinity+0x6f/0x120
 RSP: 0018:ffff88007bfe5a38  EFLAGS: 00010202
 RAX: 0000000000000010 RBX: ffff880077fd0d28 RCX: 0000000000000050
 RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000000
 RBP: ffff88007bfe5a58 R08: ffff880077f6ff00 R09: 0000000000000001
 R10: ffffffff8143e673 R11: 0000000000000001 R12: 0000000000000001
 R13: ffff880077fd0800 R14: 0000000000000000 R15: ffff88007bf489b0
 FS:  0000000000000000(0000) GS:ffff88007ea00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 0000000000000020 CR3: 0000000079f8b000 CR4: 00000000000006f0
 Stack:
  ffff880077fd0d28 0000000000000000 ffff880077fd0800 0000000000000008
  ffff88007bfe5a78 ffffffff8179b37d ffff88007bccc800 ffff88007bccc800
  ffff88007bfe5a98 ffffffff8179b3b6 ffff88007bccc800 ffff880077fd0d28
 Call Trace:
  [<ffffffff8179b37d>] virtscsi_set_affinity+0x2d/0x40
  [<ffffffff8179b3b6>] virtscsi_remove_vqs+0x26/0x50
  [<ffffffff8179c7d2>] virtscsi_remove+0x82/0xa0
  [<ffffffff814cb6b2>] virtio_dev_remove+0x22/0x70
  [<ffffffff8167ca49>] __device_release_driver+0x69/0xd0
  [<ffffffff8167cb9d>] device_release_driver+0x2d/0x40
  [<ffffffff8167bb96>] bus_remove_device+0x116/0x150
  [<ffffffff81679936>] device_del+0x126/0x1e0
  [<ffffffff81679a06>] device_unregister+0x16/0x30
  [<ffffffff814cb889>] unregister_virtio_device+0x19/0x30
  [<ffffffff814cdad6>] virtio_pci_remove+0x36/0x80
  [<ffffffff81464ae7>] pci_device_remove+0x37/0x70
  [<ffffffff8167ca49>] __device_release_driver+0x69/0xd0
  [<ffffffff8167cb9d>] device_release_driver+0x2d/0x40
  [<ffffffff8167bb96>] bus_remove_device+0x116/0x150
  [<ffffffff81679936>] device_del+0x126/0x1e0
  [<ffffffff8145edfc>] pci_stop_bus_device+0x9c/0xb0
  [<ffffffff8145f036>] pci_stop_and_remove_bus_device+0x16/0x30
  [<ffffffff81474a9e>] acpiphp_disable_slot+0x8e/0x150
  [<ffffffff81474f6a>] hotplug_event_func+0xba/0x1a0
  [<ffffffff814906c8>] ? acpi_os_release_object+0xe/0x12
  [<ffffffff81475911>] _handle_hotplug_event_func+0x31/0x70
  [<ffffffff810b5333>] process_one_work+0x183/0x500
  [<ffffffff810b66e2>] worker_thread+0x122/0x400
  [<ffffffff810b65c0>] ? manage_workers+0x2d0/0x2d0
  [<ffffffff810bc5de>] kthread+0xce/0xe0
  [<ffffffff810bc510>] ? kthread_freezable_should_stop+0x70/0x70
  [<ffffffff81ca045c>] ret_from_fork+0x7c/0xb0
  [<ffffffff810bc510>] ? kthread_freezable_should_stop+0x70/0x70
 Code: 01 00 00 00 74 59 45 31 e4 83 bb c8 01 00 00 02 74 46 66 2e 0f 1f 84 00 00 00 00 00 49 63 c4 48 c1 e0 04 48 8b bc 0
3 10 02 00 00 <48> 8b 47 20 48 8b 80 d0 01 00 00 48 8b 40 50 48 85 c0 74 07 be
 RIP  [<ffffffff8179b29f>] __virtscsi_set_affinity+0x6f/0x120
  RSP <ffff88007bfe5a38>
 CR2: 0000000000000020
 ---[ end trace 99679331a3775f48 ]---

CC: stable@vger.kernel.org
Signed-off-by: Asias He <asias@redhat.com>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-08-01 11:37:19 +09:30
Wanlong Gao 285e71ea6f virtio-scsi: reset virtqueue affinity when doing cpu hotplug
Add hot cpu notifier to reset the request virtqueue affinity
when doing cpu hotplug.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-08 23:06:56 +09:30
Paolo Bonzini 9141a4ca0d virtio-scsi: introduce multiqueue support
This patch adds queue steering to virtio-scsi.  When a target is sent
multiple requests, we always drive them to the same queue so that FIFO
processing order is kept.  However, if a target was idle, we can choose
a queue arbitrarily.  In this case the queue is chosen according to the
current VCPU, so the driver expects the number of request queues to be
equal to the number of VCPUs.  This makes it easy and fast to select
the queue, and also lets the driver optimize the IRQ affinity for the
virtqueues (each virtqueue's affinity is set to the CPU that "owns"
the queue).

The speedup comes from improving cache locality and giving CPU affinity
to the virtqueues, which is why this scheme was selected.  Assuming that
the thread that is sending requests to the device is I/O-bound, it is
likely to be sleeping at the time the ISR is executed, and thus executing
the ISR on the same processor that sent the requests is cheap.

However, the kernel will not execute the ISR on the "best" processor
unless you explicitly set the affinity.  This is because in practice
you will have many such I/O-bound processes and thus many otherwise
idle processors.  Then the kernel will execute the ISR on a random
processor, rather than the one that is sending requests to the device.

The alternative to per-CPU virtqueues is per-target virtqueues.  To
achieve the same locality, we could dynamically choose the virtqueue's
affinity based on the CPU of the last task that sent a request.  This
is less appealing because we do not set the affinity directly---we only
provide a hint to the irqbalanced running in userspace.  Dynamically
changing the affinity only works if the userspace applies the hint
fast enough.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Tested-by: Venkatesh Srinivas <venkateshs@google.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-08 23:06:55 +09:30
Paolo Bonzini 10f34f64d3 virtio-scsi: push vq lock/unlock into virtscsi_vq_done
Avoid duplicated code in all of the callers.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-08 23:06:53 +09:30
Paolo Bonzini 7f82b3c915 virtio-scsi: pass struct virtio_scsi to virtqueue completion function
This will be needed soon in order to retrieve the per-target
struct.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-08 23:06:49 +09:30
Wanlong Gao 5c370194df virtio-scsi: redo allocation of target data
virtio_scsi_target_state is now empty.  We will find new uses for it in
the next few patches, so this patch does not drop it completely.

And as James suggested, we use entries target_alloc and target_destroy
in the host template to allocate and destroy the virtio_scsi_target_state
of each target, attach this struct to scsi_target->hostdata. Now
we can get at it from the sdev with scsi_target(sdev)->hostdata.
No messing around with fixed size arrays and bulk memory allocation
and no need to pass in the maximum target size as a parameter because
everything should now happen dynamically.

Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-08 23:06:47 +09:30
Rusty Russell bf9582910b virtio_scsi: use virtqueue_add_inbuf() for virtscsi_kick_event.
It's a bit clearer, and add_buf is going away.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Asias He <asias@redhat.com>
2013-03-20 15:45:00 +10:30
Wanlong Gao 682993b4e4 virtio-scsi: use virtqueue_add_sgs for command buffers
Using the new virtqueue_add_sgs function lets us simplify the queueing
path.  In particular, all data protected by the tgt_lock is just gone
(multiqueue will find a new use for the lock).

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 15:44:59 +10:30
Wanlong Gao ba06d1e1d3 virtio-scsi: use pr_err() instead of printk()
Convert the virtio-scsi driver to use pr_err() instead of printk().

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-12 15:36:12 +10:30
Greg Kroah-Hartman 6f03979051 Drivers: scsi: remove __dev* attributes.
CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, __devinitdata,
__devinitconst, and __devexit from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Adam Radford <linuxraid@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 15:57:01 -08:00
Linus Torvalds b7dfde956d Some nice cleanups, and even a patch my wife did as a "live" demo for
Latinoware 2012.
 
 There's a slightly non-trivial merge in virtio-net, as we cleaned up the
 virtio add_buf interface while DaveM accepted the mq virtio-net patches.
 
 You can see my solution in my pending-rebases branch, if that helps, but I
 know you love merging:
 
 https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe
 
 Cheers,
 Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio update from Rusty Russell:
 "Some nice cleanups, and even a patch my wife did as a "live" demo for
  Latinoware 2012.

  There's a slightly non-trivial merge in virtio-net, as we cleaned up
  the virtio add_buf interface while DaveM accepted the mq virtio-net
  patches."

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits)
  virtio_console: Add support for remoteproc serial
  virtio_console: Merge struct buffer_token into struct port_buffer
  virtio: add drv_to_virtio to make code clearly
  virtio: use dev_to_virtio wrapper in virtio
  virtio-mmio: Fix irq parsing in command line parameter
  virtio_console: Free buffers from out-queue upon close
  virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>(
  virtio_console: Use kmalloc instead of kzalloc
  virtio_console: Free buffer if splice fails
  virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: make virtqueue_add_buf() returning 0 on success, not capacity.
  virtio: console: don't rely on virtqueue_add_buf() returning capacity.
  virtio_net: don't rely on virtqueue_add_buf() returning capacity.
  virtio-net: remove unused skb_vnet_hdr->num_sg field
  virtio-net: correct capacity math on ring full
  virtio: move queue_index and num_free fields into core struct virtqueue.
  ...
2012-12-20 08:37:05 -08:00
Rusty Russell 4614e51ccc virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0
We simplified virtqueue_add_buf(), make it clear in the callers.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:37 +10:30
Eric Northup b56d100351 [SCSI] virtio_scsi: fix memory leak on full queue condition.
virtscsi_queuecommand was leaking memory when the virtio queue was full.

Tested: Guest operates correctly even with very small queue sizes, validated
we're not leaking kmalloc-192 sized allocations anymore.

Signed-off-by: Eric Northup <digitaleric@google.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-11-27 08:59:45 +04:00
Paolo Bonzini 865b58c05b [SCSI] virtio-scsi: support online resizing of disks
Support the LUN parameter change event.  Currently, the host fires this event
when the capacity of a disk is changed from the virtual machine monitor.
The resize then appears in the kernel log like this:

  sd 0:0:0:0: [sda] 46137344 512-byte logical blocks: (23.6 GB/22.0 GIb)
  sda: detected capacity change from 22548578304 to 23622320128

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-10-09 11:24:47 +01:00
Paolo Bonzini 9da5f5ac6a [SCSI] virtio-scsi: fix LUNs greater than 255
virtio-scsi needs to report LUNs greater than 256 using the "flat"
format.  Because the Linux SCSI layer just maps the SCSI LUN to
an u32, without any parsing, these end up in the range from 16640
to 32767.  Fix max_lun to account for the possibility that logical
unit numbers are encoded with the "flat" format.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-10-09 11:23:28 +01:00