linux-toradex.git/drivers/vhost, branch v5.10-rc6

vhost scsi: Add support for LUN resets.

2020-11-15T22:30:55+00:00

In newer versions of virtio-scsi we just reset the timer when an a
command times out, so TMFs are never sent for the cmd time out case.
However, in older kernels and for the TMF inject cases, we can still get
resets and we end up just failing immediately so the guest might see the
device get offlined and IO errors.

For the older kernel cases, we want the same end result as the
modern virtio-scsi driver where we let the lower levels fire their error
handling and handle the problem. And at the upper levels we want to
wait. This patch ties the LUN reset handling into the LIO TMF code which
will just wait for outstanding commands to complete like we are doing in
the modern virtio-scsi case.

Note: I did not handle the ABORT case to keep this simple. For ABORTs
LIO just waits on the cmd like how it does for the RESET case. If
an ABORT fails, the guest OS ends up escalating to LUN RESET, so in
the end we get the same behavior where we wait on the outstanding
cmds.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/1604986403-4931-6-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin 
Acked-by: Stefan Hajnoczi

vhost scsi: add lun parser helper

2020-11-15T22:30:55+00:00

Move code to parse lun from req's lun_buf to helper, so tmf code
can use it in the next patch.

Signed-off-by: Mike Christie 
Reviewed-by: Paolo Bonzini 
Acked-by: Jason Wang 
Link: https://lore.kernel.org/r/1604986403-4931-5-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin 
Acked-by: Stefan Hajnoczi

vhost scsi: fix cmd completion race

2020-11-15T22:30:55+00:00

We might not do the final se_cmd put from vhost_scsi_complete_cmd_work.
When the last put happens a little later then we could race where
vhost_scsi_complete_cmd_work does vhost_signal, the guest runs and sends
more IO, and vhost_scsi_handle_vq runs but does not find any free cmds.

This patch has us delay completing the cmd until the last lio core ref
is dropped. We then know that once we signal to the guest that the cmd
is completed that if it queues a new command it will find a free cmd.

Signed-off-by: Mike Christie 
Reviewed-by: Maurizio Lombardi 
Link: https://lore.kernel.org/r/1604986403-4931-4-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin 
Acked-by: Stefan Hajnoczi

vhost scsi: alloc cmds per vq instead of session

2020-11-15T22:30:55+00:00

We currently are limited to 256 cmds per session. This leads to problems
where if the user has increased virtqueue_size to more than 2 or
cmd_per_lun to more than 256 vhost_scsi_get_tag can fail and the guest
will get IO errors.

This patch moves the cmd allocation to per vq so we can easily match
whatever the user has specified for num_queues and
virtqueue_size/cmd_per_lun. It also makes it easier to control how much
memory we preallocate. For cases, where perf is not as important and
we can use the current defaults (1 vq and 128 cmds per vq) memory use
from preallocate cmds is cut in half. For cases, where we are willing
to use more memory for higher perf, cmd mem use will now increase as
the num queues and queue depth increases.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/1604986403-4931-3-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Maurizio Lombardi 
Acked-by: Stefan Hajnoczi

vhost: add helper to check if a vq has been setup

2020-11-15T22:30:54+00:00

This adds a helper check if a vq has been setup. The next patches
will use this when we move the vhost scsi cmd preallocation from per
session to per vq. In the per vq case, we only want to allocate cmds
for vqs that have actually been setup and not for all the possible
vqs.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/1604986403-4931-2-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin 
Acked-by: Jason Wang 
Acked-by: Stefan Hajnoczi

vdpa: handle irq bypass register failure case

2020-10-30T08:02:53+00:00

LKP considered variable 'ret' in vhost_vdpa_setup_vq_irq() as
a unused variable, so suggest we remove it. Actually it stores
return value of irq_bypass_register_producer(), but we did not
check it, we should handle the failure case.

This commit will print a message if irq bypass register producer
fail, in this case, vqs still remain functional.

Signed-off-by: Zhu Lingshan 
Reported-by: kernel test robot 
Link: https://lore.kernel.org/r/20201023104046.404794-1-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin 
Acked-by: Jason Wang

Revert "vhost-vdpa: fix page pinning leakage in error path"

2020-10-30T08:02:39+00:00

This reverts commit 7ed9e3d97c32d969caded2dfb6e67c1a2cc5a0b1.

The patch creates a DoS risk since it can result in a high order memory
allocation.

Fixes: 7ed9e3d97c32d ("vhost-vdpa: fix page pinning leakage in error path")
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin

vhost_vdpa: Return -EFAULT if copy_from_user() fails

2020-10-30T08:02:25+00:00

The copy_to/from_user() functions return the number of bytes which we
weren't able to copy but the ioctl should return -EFAULT if they fail.

Fixes: a127c5bbb6a8 ("vhost-vdpa: fix backend feature ioctls")
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20201023120853.GI282278@mwanda
Signed-off-by: Michael S. Tsirkin 
Cc: stable@vger.kernel.org
Acked-by: Jason Wang

vhost: vdpa: report iova range

2020-10-23T15:55:28+00:00

This patch introduces a new ioctl for vhost-vdpa device that can
report the iova range by the device.

For device that implements get_iova_range() method, we fetch it from
the vDPA device. If device doesn't implement get_iova_range() but
depends on platform IOMMU, we will query via DOMAIN_ATTR_GEOMETRY,
otherwise [0, ULLONG_MAX] is assumed.

For safety, this patch also rules out the map request which is not in
the valid range.

Signed-off-by: Jason Wang 
Link: https://lore.kernel.org/r/20201023090043.14430-3-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin

vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call

2020-10-21T14:48:10+00:00

This commit removed unnecessary spin_locks in vhost_vring_call
and related operations. Because we manipulate irq offloading
contents in vhost_vdpa ioctl code path which is already
protected by dev mutex and vq mutex.

Signed-off-by: Zhu Lingshan 
Link: https://lore.kernel.org/r/20200909065234.3313-1-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin 
Acked-by: Jason Wang