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path: root/drivers/scsi/virtio_scsi.c
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2019-04-10scsi: virtio_scsi: limit number of hw queues by nr_cpu_idsDongli Zhang1-0/+1
When tag_set->nr_maps is 1, the block layer limits the number of hw queues by nr_cpu_ids. No matter how many hw queues are used by virtio-scsi, as it has (tag_set->nr_maps == 1), it can use at most nr_cpu_ids hw queues. In addition, specifically for pci scenario, when the 'num_queues' specified by qemu is more than maxcpus, virtio-scsi would not be able to allocate more than maxcpus vectors in order to have a vector for each queue. As a result, it falls back into MSI-X with one vector for config and one shared for queues. Considering above reasons, this patch limits the number of hw queues used by virtio-scsi by nr_cpu_ids. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-03-19scsi: virtio_scsi: Use HCTX_TYPE_DEFAULT for blk_mq_tag_set->mapDongli Zhang1-1/+1
Use HCTX_TYPE_DEFAULT instead of 0 to avoid hardcoding. Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-03-06scsi: virtio_scsi: don't send sc payload with tmfsFelipe Franciosi1-2/+0
The virtio scsi spec defines struct virtio_scsi_ctrl_tmf as a set of device-readable records and a single device-writable response entry: struct virtio_scsi_ctrl_tmf { // Device-readable part le32 type; le32 subtype; u8 lun[8]; le64 id; // Device-writable part u8 response; } The above should be organised as two descriptor entries (or potentially more if using VIRTIO_F_ANY_LAYOUT), but without any extra data after "le64 id" or after "u8 response". The Linux driver doesn't respect that, with virtscsi_abort() and virtscsi_device_reset() setting cmd->sc before calling virtscsi_tmf(). It results in the original scsi command payload (or writable buffers) added to the tmf. This fixes the problem by leaving cmd->sc zeroed out, which makes virtscsi_kick_cmd() add the tmf to the control vq without any payload. Cc: stable@vger.kernel.org Signed-off-by: Felipe Franciosi <felipe@nutanix.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-02-05scsi: remove bidirectional command supportChristoph Hellwig1-11/+3
No real need for bidi support once the OSD code is gone. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-28Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-53/+0
Pull SCSI updates from James Bottomley: "This is mostly update of the usual drivers: smarpqi, lpfc, qedi, megaraid_sas, libsas, zfcp, mpt3sas, hisi_sas. Additionally, we have a pile of annotation, unused variable and minor updates. The big API change is the updates for Christoph's DMA rework which include removing the DISABLE_CLUSTERING flag. And finally there are a couple of target tree updates" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (259 commits) scsi: isci: request: mark expected switch fall-through scsi: isci: remote_node_context: mark expected switch fall-throughs scsi: isci: remote_device: Mark expected switch fall-throughs scsi: isci: phy: Mark expected switch fall-through scsi: iscsi: Capture iscsi debug messages using tracepoints scsi: myrb: Mark expected switch fall-throughs scsi: megaraid: fix out-of-bound array accesses scsi: mpt3sas: mpt3sas_scsih: Mark expected switch fall-through scsi: fcoe: remove set but not used variable 'port' scsi: smartpqi: call pqi_free_interrupts() in pqi_shutdown() scsi: smartpqi: fix build warnings scsi: smartpqi: update driver version scsi: smartpqi: add ofa support scsi: smartpqi: increase fw status register read timeout scsi: smartpqi: bump driver version scsi: smartpqi: add smp_utils support scsi: smartpqi: correct lun reset issues scsi: smartpqi: correct volume status scsi: smartpqi: do not offline disks for transient did no connect conditions scsi: smartpqi: allow for larger raid maps ...
2018-12-18scsi: flip the default on use_clusteringChristoph Hellwig1-1/+0
Most SCSI drivers want to enable "clustering", that is merging of segments so that they might span more than a single page. Remove the ENABLE_CLUSTERING define, and require drivers to explicitly set DISABLE_CLUSTERING to disable this feature. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-18scsi: virtio_scsi: Remove per-target data because it is no longer usedBart Van Assche1-52/+0
Commit b5b6e8c8d3b4 ("scsi: virtio_scsi: fix IO hang caused by automatic irq vector affinity") removed all virtio_scsi hostdata users. Since the SCSI host data is no longer used, also remove the host data itself. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Hannes Reinecke <hare@suse.de> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-11-07blk-mq: abstract out queue mapJens Axboe1-1/+2
This is in preparation for allowing multiple sets of maps per queue, if so desired. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-26scsi: virtio_scsi: fix pi_bytes{out,in} on 4 KiB block size devicesGreg Edwards1-4/+4
When the underlying device is a 4 KiB logical block size device with a protection interval exponent of 0, i.e. 4096 bytes data + 8 bytes PI, the driver miscalculates the pi_bytes{out,in} by a factor of 8x (64 bytes). This leads to errors on all reads and writes on 4 KiB logical block size devices when CONFIG_BLK_DEV_INTEGRITY is enabled and the VIRTIO_SCSI_F_T10_PI feature bit has been negotiated. Fixes: e6dc783a38ec0 ("virtio-scsi: Enable DIF/DIX modes in SCSI host LLD") Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Edwards <gedwards@ddn.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook1-3/+4
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-03-14scsi: virtio_scsi: unify scsi_host_templateMing Lei1-59/+15
Now that virtio_scsi uses blk-mq exclusively, we can remove the scsi_host_template and associated plumbing for the legacy I/O path. [mkp: commit desc] Cc: Omar Sandoval <osandov@fb.com>, Cc: "Martin K. Petersen" <martin.petersen@oracle.com>, Cc: James Bottomley <james.bottomley@hansenpartnership.com>, Cc: Christoph Hellwig <hch@lst.de>, Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Laurence Oberman <loberman@redhat.com> Cc: Hannes Reinecke <hare@suse.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Suggested-by: Christoph Hellwig <hch@lst.de>, Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-03-14scsi: virtio_scsi: fix IO hang caused by automatic irq vector affinityMing Lei1-56/+3
Since commit 84676c1f21e8ff5 ("genirq/affinity: assign vectors to all possible CPUs") it is possible to end up in a scenario where only offline CPUs are mapped to an interrupt vector. This is only an issue for the legacy I/O path since with blk-mq/scsi-mq an I/O can't be submitted to a hardware queue if the queue isn't mapped to an online CPU. Fix this issue by forcing virtio-scsi to use blk-mq. [mkp: commit desc] Cc: Omar Sandoval <osandov@fb.com>, Cc: "Martin K. Petersen" <martin.petersen@oracle.com>, Cc: James Bottomley <james.bottomley@hansenpartnership.com>, Cc: Christoph Hellwig <hch@lst.de>, Cc: Don Brace <don.brace@microsemi.com> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Laurence Oberman <loberman@redhat.com> Fixes: 84676c1f21e8 ("genirq/affinity: assign vectors to all possible CPUs") Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-24scsi: virtio: virtio_scsi: Set can_queue to the length of the virtqueue.Richard W.M. Jones1-2/+2
Since switching to blk-mq as the default in commit 5c279bd9e406 ("scsi: default to scsi-mq"), virtio-scsi LUNs consume about 10x as much kernel memory. qemu currently allocates a fixed 128 entry virtqueue. can_queue currently is set to 1024. But with indirect descriptors, each command in the queue takes 1 virtqueue entry, so the number of commands which can be queued is equal to the length of the virtqueue. Note I intend to send a patch to qemu to allow the virtqueue size to be configured from the qemu command line. Signed-off-by: Richard W.M. Jones <rjones@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-07-12scsi: virtio_scsi: always read VPD pages for multiqueue tooPaolo Bonzini1-0/+1
Multi-queue virtio-scsi uses a different scsi_host_template struct. Add the .device_alloc field there, too. Fixes: 25d1d50e23275e141e3a3fe06c25a99f4c4bf4e0 Cc: stable@vger.kernel.org Cc: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-26scsi: virtio_scsi: let host do exception handlingPaolo Bonzini1-0/+12
virtio_scsi tries to do exception handling after the default 30 seconds timeout expires. However, it's better to let the host control the timeout, otherwise with a heavy I/O load it is likely that an abort will also timeout. This leads to fatal errors like filesystems going offline. Disable the 'sd' timeout and allow the host to do exception handling, following the precedent of the storvsc driver. Hannes has a proposal to introduce timeouts in virtio, but this provides an immediate solution for stable kernels too. [mkp: fixed typo] Reported-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Hannes Reinecke <hare@suse.de> Cc: linux-scsi@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-12scsi: virtio_scsi: Remove code that zeroes driver-private command dataBart Van Assche1-1/+0
Since the SCSI core zeroes driver-private command data, remove that code from the virtio driver. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-05-10Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-2/+1
Pull virtio updates from Michael Tsirkin: "Fixes, cleanups, performance A bunch of changes to virtio, most affecting virtio net. Also ptr_ring batched zeroing - first of batching enhancements that seems ready." * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: s390/virtio: change maintainership tools/virtio: fix spelling mistake: "wakeus" -> "wakeups" virtio_net: tidy a couple debug statements ptr_ring: support testing different batching sizes ringtest: support test specific parameters ptr_ring: batch ring zeroing virtio: virtio_driver doc virtio_net: don't reset twice on XDP on/off virtio_net: fix support for small rings virtio_net: reduce alignment for buffers virtio_net: rework mergeable buffer handling virtio_net: allow specifying context for rx virtio: allow extra context per descriptor tools/virtio: fix build breakage virtio: add context flag to find vqs virtio: wrap find_vqs ringtest: fix an assert statement
2017-05-02virtio: wrap find_vqsMichael S. Tsirkin1-2/+1
We are going to add more parameters to find_vqs, let's wrap the call so we don't need to tweak all drivers every time. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-19scsi: virtio_scsi: Always try to read VPD pagesDavid Gibson1-0/+24
Passed through SCSI targets may have transfer limits which come from the host SCSI controller or something on the host side other than the target itself. To make this work properly, the hypervisor can adjust the target's VPD information to advertise these limits. But for that to work, the guest has to look at the VPD pages, which we won't do by default if it is an SPC-2 device, even if it does actually support it. This adds a workaround to address this, forcing devices attached to a virtio-scsi controller to always check the VPD pages. This is modelled on a similar workaround for the storvsc (Hyper-V) SCSI controller, although that exists for slightly different reasons. A specific case which causes this is a volume from IBM's IPR RAID controller (which presents as an SPC-2 device, although it does support VPD) passed through with qemu's 'scsi-block' device. [mkp: fixed typo] Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-02-27virtio_scsi: use virtio IRQ affinityChristoph Hellwig1-114/+12
Use automatic IRQ affinity assignment in the virtio layer if available, and build the blk-mq queues based on it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27virtio: allow drivers to request IRQ affinity when creating VQsChristoph Hellwig1-1/+2
Add a struct irq_affinity pointer to the find_vqs methods, which if set is used to tell the PCI layer to create the MSI-X vectors for our I/O virtqueues with the proper affinity from the start. Compared to after the fact affinity hints this gives us an instantly working setup and allows to allocate the irq descritors node-local and avoid interconnect traffic. Last but not least this will allow blk-mq queues are created based on the interrupt affinity for storage drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-20scsi: virtio_scsi: Reject commands when virtqueue is brokenEric Farman1-1/+10
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>
2016-10-07Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-1/+1
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 ...
2016-09-19virtio scsi: Convert to hotplug state machineSebastian Andrzej Siewior1-27/+49
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>
2016-09-14scsi: virtio_scsi: Use complete() instead complete_all()Daniel Wagner1-1/+1
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>
2015-07-23Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-1/+3
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
2015-07-07virtio scsi: fix unused variable warningStephen Rothwell1-1/+3
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>
2015-05-25virtio_scsi: don't select CONFIG_BLK_DEV_INTEGRITYChristoph Hellwig1-1/+10
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>
2015-01-21virtio/scsi: verify device has config spaceMichael S. Tsirkin1-0/+6
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>
2014-12-11Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-19/+31
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 ...
2014-12-09virtio: drop VIRTIO_F_VERSION_1 from driversMichael S. Tsirkin1-1/+0
Core activates this bit automatically now, drop it from drivers that set it explicitly. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09virtio_scsi: v1.0 supportMichael S. Tsirkin1-19/+32
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>
2014-11-24scsi: drop reason argument from ->change_queue_depthChristoph Hellwig1-6/+2
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>
2014-11-24scsi: avoid ->change_queue_depth indirection for queue full trackingChristoph Hellwig1-12/+3
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>
2014-11-20virtio_scsi: support multi hw queue of blk-mqMing Lei1-1/+16
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>
2014-11-12scsi: don't set tagging state from scsi_adjust_queue_depthChristoph Hellwig1-3/+1
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>
2014-10-15virtio_scsi: drop scan callbackMichael S. Tsirkin1-16/+7
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>
2014-10-15virtio_scsi: fix race on device removalMichael S. Tsirkin1-1/+10
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>
2014-10-15virito_scsi: use freezable WQ for eventsPaolo Bonzini1-1/+1
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>
2014-10-15virtio_scsi: enable VQs early on restoreMichael S. Tsirkin1-0/+2
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>
2014-10-15virtio_scsi: move kick event out from virtscsi_initMichael S. Tsirkin1-5/+11
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>
2014-07-25virtio-scsi: Implement change_queue_depth for virtscsi targetsVenkatesh Srinivas1-0/+33
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>
2014-07-25virtio-scsi: replace target spinlock with seqcountMing Lei1-13/+29
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>
2014-06-25virtio-scsi: fix various bad behavior on aborted requestsPaolo Bonzini1-0/+22
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>
2014-06-25virtio-scsi: avoid cancelling uninitialized work itemsPaolo Bonzini1-1/+3
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>
2014-06-12Merge branch 'for-next' of ↵Linus Torvalds1-17/+69
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 ...
2014-06-11Merge tag 'virtio-next-for-linus' of ↵Linus Torvalds1-9/+6
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.
2014-06-02virtio-scsi: Enable DIF/DIX modes in SCSI host LLDNicholas Bellinger1-18/+69
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>
2014-05-21virtio_scsi: don't call virtqueue_add_sgs(... GFP_NOIO) holding spinlock.Rusty Russell1-9/+6
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>
2014-05-19virtio_scsi: use cmd_sizeChristoph Hellwig1-18/+7
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>