Commit Graph

105 Commits

Author SHA1 Message Date
Dan Carpenter be9c6bad9b vdpa: potential uninitialized return in vhost_vdpa_va_map()
The concern here is that "ret" can be uninitialized if we hit the
"goto next" condition on every iteration through the loop.

Fixes: 41ba1b5f9d4b ("vdpa: Support transferring virtual addressing during DMA mapping")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210907073253.GB18254@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2021-09-14 18:10:43 -04:00
Xie Yongji d8945ec411 vdpa: Support transferring virtual addressing during DMA mapping
This patch introduces an attribute for vDPA device to indicate
whether virtual address can be used. If vDPA device driver set
it, vhost-vdpa bus driver will not pin user page and transfer
userspace virtual address instead of physical address during
DMA mapping. And corresponding vma->vm_file and offset will be
also passed as an opaque pointer.

Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-11-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:57 -04:00
Xie Yongji 22af48cf91 vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap()
The upcoming patch is going to support VA mapping/unmapping.
So let's factor out the logic of PA mapping/unmapping firstly
to make the code more readable.

Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-10-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:57 -04:00
Xie Yongji c10fb9454a vdpa: Add an opaque pointer for vdpa_config_ops.dma_map()
Add an opaque pointer for DMA mapping.

Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-9-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:57 -04:00
Xie Yongji 7f05630dc6 vhost-vdpa: Handle the failure of vdpa_reset()
The vdpa_reset() may fail now. This adds check to its return
value and fail the vhost_vdpa_open().

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-7-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:57 -04:00
Xie Yongji 0686082dbf vdpa: Add reset callback in vdpa_config_ops
This adds a new callback to support device specific reset
behavior. The vdpa bus driver will call the reset function
instead of setting status to zero during resetting.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210831103634.33-6-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:57 -04:00
Cai Huoqing 729ce5a5bd vdpa: Make use of PFN_PHYS/PFN_UP/PFN_DOWN helper macro
it's a nice refactor to make use of
PFN_PHYS/PFN_UP/PFN_DOWN helper macro

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20210802013717.851-1-caihuoqing@baidu.com
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 02:25:16 -04:00
Xie Yongji 0e398290cf vhost-vdpa: Fix integer overflow in vhost_vdpa_process_iotlb_update()
The "msg->iova + msg->size" addition can have an integer overflow
if the iotlb message is from a malicious user space application.
So let's fix it.

Fixes: 1b48dc03e5 ("vhost: vdpa: report iova range")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210728130756.97-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-08-10 11:52:23 -04:00
Jason Wang 530a5678bc vdpa: support packed virtqueue for set/get_vq_state()
This patch extends the vdpa_vq_state to support packed virtqueue
state which is basically the device/driver ring wrap counters and the
avail and used index. This will be used for the virito-vdpa support
for the packed virtqueue and the future vhost/vhost-vdpa support for
the packed virtqueue.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210602021536.39525-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
2021-07-08 07:49:01 -04:00
Linus Torvalds 16bb86b556 virtio,vhost,vdpa: features, fixes
A bunch of new drivers including vdpa support for block
 and virtio-vdpa. Beginning of vq kick (aka doorbell) mapping support.
 Misc fixes.
 
 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:
 "A bunch of new drivers including vdpa support for block and
  virtio-vdpa.

  Beginning of vq kick (aka doorbell) mapping support.

  Misc fixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (40 commits)
  virtio_pci_modern: correct sparse tags for notify
  virtio_pci_modern: __force cast the notify mapping
  vDPA/ifcvf: get_config_size should return dev specific config size
  vDPA/ifcvf: enable Intel C5000X-PL virtio-block for vDPA
  vDPA/ifcvf: deduce VIRTIO device ID when probe
  vdpa_sim_blk: add support for vdpa management tool
  vdpa_sim_blk: handle VIRTIO_BLK_T_GET_ID
  vdpa_sim_blk: implement ramdisk behaviour
  vdpa: add vdpa simulator for block device
  vhost/vdpa: Remove the restriction that only supports virtio-net devices
  vhost/vdpa: use get_config_size callback in vhost_vdpa_config_validate()
  vdpa: add get_config_size callback in vdpa_config_ops
  vdpa_sim: cleanup kiovs in vdpasim_free()
  vringh: add vringh_kiov_length() helper
  vringh: implement vringh_kiov_advance()
  vringh: explain more about cleaning riov and wiov
  vringh: reset kiov 'consumed' field in __vringh_iov()
  vringh: add 'iotlb_lock' to synchronize iotlb accesses
  vdpa_sim: use iova module to allocate IOVA addresses
  vDPA/ifcvf: deduce VIRTIO device ID from pdev ids
  ...
2021-05-05 13:31:39 -07:00
Xie Yongji 9d6d97bff7 vhost/vdpa: Remove the restriction that only supports virtio-net devices
Since the config checks are done by the vDPA drivers, we can remove the
virtio-net restriction and we should be able to support all kinds of
virtio devices.

<linux/virtio_net.h> is not needed anymore, but we need to include
<linux/slab.h> to avoid compilation failures.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210315163450.254396-11-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2021-05-03 04:55:53 -04:00
Stefano Garzarella d6d8bb92fd vhost/vdpa: use get_config_size callback in vhost_vdpa_config_validate()
Let's use the new 'get_config_size()' callback available instead of
using the 'virtio_id' to get the size of the device config space.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210315163450.254396-10-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2021-05-03 04:55:53 -04:00
Jason Wang 3a3e0fad16 vhost-vdpa: fix vm_flags for virtqueue doorbell mapping
The virtqueue doorbell is usually implemented via registeres but we
don't provide the necessary vma->flags like VM_PFNMAP. This may cause
several issues e.g when userspace tries to map the doorbell via vhost
IOTLB, kernel may panic due to the page is not backed by page
structure. This patch fixes this by setting the necessary
vm_flags. With this patch, try to map doorbell via IOTLB will fail
with bad address.

Cc: stable@vger.kernel.org
Fixes: ddd89d0a05 ("vhost_vdpa: support doorbell mapping via mmap")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210413091557.29008-1-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-05-03 04:55:52 -04:00
Linus Torvalds 4f9701057a IOMMU Updates for Linux v5.13
Including:
 
 	- Big cleanup of almost unsused parts of the IOMMU API by
 	  Christoph Hellwig. This mostly affects the Freescale PAMU
 	  driver.
 
 	- New IOMMU driver for Unisoc SOCs
 
 	- ARM SMMU Updates from Will:
 
 	  - SMMUv3: Drop vestigial PREFETCH_ADDR support
 	  - SMMUv3: Elide TLB sync logic for empty gather
 	  - SMMUv3: Fix "Service Failure Mode" handling
     	  - SMMUv2: New Qualcomm compatible string
 
 	- Removal of the AMD IOMMU performance counter writeable check
 	  on AMD. It caused long boot delays on some machines and is
 	  only needed to work around an errata on some older (possibly
 	  pre-production) chips. If someone is still hit by this
 	  hardware issue anyway the performance counters will just
 	  return 0.
 
 	- Support for targeted invalidations in the AMD IOMMU driver.
 	  Before that the driver only invalidated a single 4k page or the
 	  whole IO/TLB for an address space. This has been extended now
 	  and is mostly useful for emulated AMD IOMMUs.
 
 	- Several fixes for the Shared Virtual Memory support in the
 	  Intel VT-d driver
 
 	- Mediatek drivers can now be built as modules
 
 	- Re-introduction of the forcedac boot option which got lost
 	  when converting the Intel VT-d driver to the common dma-iommu
 	  implementation.
 
 	- Extension of the IOMMU device registration interface and
 	  support iommu_ops to be const again when drivers are built as
 	  modules.
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Merge tag 'iommu-updates-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - Big cleanup of almost unsused parts of the IOMMU API by Christoph
   Hellwig. This mostly affects the Freescale PAMU driver.

 - New IOMMU driver for Unisoc SOCs

 - ARM SMMU Updates from Will:
     - Drop vestigial PREFETCH_ADDR support (SMMUv3)
     - Elide TLB sync logic for empty gather (SMMUv3)
     - Fix "Service Failure Mode" handling (SMMUv3)
     - New Qualcomm compatible string (SMMUv2)

 - Removal of the AMD IOMMU performance counter writeable check on AMD.
   It caused long boot delays on some machines and is only needed to
   work around an errata on some older (possibly pre-production) chips.
   If someone is still hit by this hardware issue anyway the performance
   counters will just return 0.

 - Support for targeted invalidations in the AMD IOMMU driver. Before
   that the driver only invalidated a single 4k page or the whole IO/TLB
   for an address space. This has been extended now and is mostly useful
   for emulated AMD IOMMUs.

 - Several fixes for the Shared Virtual Memory support in the Intel VT-d
   driver

 - Mediatek drivers can now be built as modules

 - Re-introduction of the forcedac boot option which got lost when
   converting the Intel VT-d driver to the common dma-iommu
   implementation.

 - Extension of the IOMMU device registration interface and support
   iommu_ops to be const again when drivers are built as modules.

* tag 'iommu-updates-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (84 commits)
  iommu: Streamline registration interface
  iommu: Statically set module owner
  iommu/mediatek-v1: Add error handle for mtk_iommu_probe
  iommu/mediatek-v1: Avoid build fail when build as module
  iommu/mediatek: Always enable the clk on resume
  iommu/fsl-pamu: Fix uninitialized variable warning
  iommu/vt-d: Force to flush iotlb before creating superpage
  iommu/amd: Put newline after closing bracket in warning
  iommu/vt-d: Fix an error handling path in 'intel_prepare_irq_remapping()'
  iommu/vt-d: Fix build error of pasid_enable_wpe() with !X86
  iommu/amd: Remove performance counter pre-initialization test
  Revert "iommu/amd: Fix performance counter initialization"
  iommu/amd: Remove duplicate check of devid
  iommu/exynos: Remove unneeded local variable initialization
  iommu/amd: Page-specific invalidations for more than one page
  iommu/arm-smmu-v3: Remove the unused fields for PREFETCH_CONFIG command
  iommu/vt-d: Avoid unnecessary cache flush in pasid entry teardown
  iommu/vt-d: Invalidate PASID cache when root/context entry changed
  iommu/vt-d: Remove WO permissions on second-level paging entries
  iommu/vt-d: Report the right page fault address
  ...
2021-05-01 09:33:00 -07:00
Xie Yongji a9d064524f vhost-vdpa: protect concurrent access to vhost device iotlb
Protect vhost device iotlb by vhost_dev->mutex. Otherwise,
it might cause corruption of the list and interval tree in
struct vhost_iotlb if userspace sends the VHOST_IOTLB_MSG_V2
message concurrently.

Fixes: 4c8cf318("vhost: introduce vDPA-based backend")
Cc: stable@vger.kernel.org
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210412095512.178-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-04-22 18:15:31 -04:00
Joerg Roedel 49d11527e5 Merge branches 'iommu/fixes', 'arm/mediatek', 'arm/smmu', 'arm/exynos', 'unisoc', 'x86/vt-d', 'x86/amd' and 'core' into next 2021-04-16 17:16:03 +02:00
Christoph Hellwig bc9a05eef1 iommu: remove DOMAIN_ATTR_GEOMETRY
The geometry information can be trivially queried from the iommu_domain
struture.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Li Yang <leoyang.li@nxp.com>
Link: https://lore.kernel.org/r/20210401155256.298656-16-hch@lst.de
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-04-07 10:56:53 +02:00
Stefano Garzarella 0bde59c172 vhost-vdpa: set v->config_ctx to NULL if eventfd_ctx_fdget() fails
In vhost_vdpa_set_config_call() if eventfd_ctx_fdget() fails the
'v->config_ctx' contains an error instead of a valid pointer.

Since we consider 'v->config_ctx' valid if it is not NULL, we should
set it to NULL in this case to avoid to use an invalid pointer in
other functions such as vhost_vdpa_config_put().

Fixes: 776f395004 ("vhost_vdpa: Support config interrupt in vdpa")
Cc: lingshan.zhu@intel.com
Cc: stable@vger.kernel.org
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210311135257.109460-3-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2021-03-14 18:10:07 -04:00
Stefano Garzarella f6bbf0010b vhost-vdpa: fix use-after-free of v->config_ctx
When the 'v->config_ctx' eventfd_ctx reference is released we didn't
set it to NULL. So if the same character device (e.g. /dev/vhost-vdpa-0)
is re-opened, the 'v->config_ctx' is invalid and calling again
vhost_vdpa_config_put() causes use-after-free issues like the
following refcount_t underflow:

    refcount_t: underflow; use-after-free.
    WARNING: CPU: 2 PID: 872 at lib/refcount.c:28 refcount_warn_saturate+0xae/0xf0
    RIP: 0010:refcount_warn_saturate+0xae/0xf0
    Call Trace:
     eventfd_ctx_put+0x5b/0x70
     vhost_vdpa_release+0xcd/0x150 [vhost_vdpa]
     __fput+0x8e/0x240
     ____fput+0xe/0x10
     task_work_run+0x66/0xa0
     exit_to_user_mode_prepare+0x118/0x120
     syscall_exit_to_user_mode+0x21/0x50
     ? __x64_sys_close+0x12/0x40
     do_syscall_64+0x45/0x50
     entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 776f395004 ("vhost_vdpa: Support config interrupt in vdpa")
Cc: lingshan.zhu@intel.com
Cc: stable@vger.kernel.org
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210311135257.109460-2-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Zhu Lingshan <lingshan.zhu@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2021-03-14 18:10:07 -04:00
Gautam Dawar 4c050286bb vhost_vdpa: fix the missing irq_bypass_unregister_producer() invocation
When qemu with vhost-vdpa netdevice is run for the first time,
it works well. But after the VM is powered off, the next qemu run
causes kernel panic due to a NULL pointer dereference in
irq_bypass_register_producer().

When the VM is powered off, vhost_vdpa_clean_irq() misses on calling
irq_bypass_unregister_producer() for irq 0 because of the existing check.

This leaves stale producer nodes, which are reset in
vhost_vring_call_reset() when vhost_dev_init() is invoked during the
second qemu run.

As the node member of struct irq_bypass_producer is also initialized
to zero, traversal on the producers list causes crash due to NULL
pointer dereference.

Fixes: 2cf1ba9a4d ("vhost_vdpa: implement IRQ offloading in vhost_vdpa")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211711
Signed-off-by: Gautam Dawar <gdawar.xilinx@gmail.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210224114845.104173-1-gdawar.xilinx@gmail.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-03-14 04:37:36 -04:00
Tian Tao 0ab4b8901a vhost_vdpa: switch to vmemdup_user()
Replace opencoded alloc and copy with vmemdup_user()

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1605057288-60400-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2020-12-18 16:14:28 -05:00
Dan Carpenter 2c602741b5 vhost_vdpa: return -EFAULT if copy_to_user() fails
The copy_to_user() function returns the number of bytes remaining to be
copied but this should return -EFAULT to the user.

Fixes: 1b48dc03e5 ("vhost: vdpa: report iova range")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/X8c32z5EtDsMyyIL@mwanda
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2020-12-02 04:36:40 -05:00
Si-Wei Liu ad89653f79 vhost-vdpa: fix page pinning leakage in error path (rework)
Pinned pages are not properly accounted particularly when
mapping error occurs on IOTLB update. Clean up dangling
pinned pages for the error path.

The memory usage for bookkeeping pinned pages is reverted
to what it was before: only one single free page is needed.
This helps reduce the host memory demand for VM with a large
amount of memory, or in the situation where host is running
short of free memory.

Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Link: https://lore.kernel.org/r/1604618793-4681-1-git-send-email-si-wei.liu@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-11-25 04:29:07 -05:00
Zhu Lingshan e01afe36df vdpa: handle irq bypass register failure case
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 <lingshan.zhu@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20201023104046.404794-1-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-10-30 04:02:53 -04:00
Michael S. Tsirkin 5e1a3149ee Revert "vhost-vdpa: fix page pinning leakage in error path"
This reverts commit 7ed9e3d97c.

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

Fixes: 7ed9e3d97c ("vhost-vdpa: fix page pinning leakage in error path")
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-10-30 04:02:39 -04:00
Dan Carpenter 7922460e33 vhost_vdpa: Return -EFAULT if copy_from_user() fails
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: a127c5bbb6 ("vhost-vdpa: fix backend feature ioctls")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20201023120853.GI282278@mwanda
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: Jason Wang <jasowang@redhat.com>
2020-10-30 04:02:25 -04:00
Jason Wang 1b48dc03e5 vhost: vdpa: report iova range
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 <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20201023090043.14430-3-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-10-23 11:55:28 -04:00
Zhu Lingshan 86e182fe12 vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call
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 <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20200909065234.3313-1-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-10-21 10:48:10 -04:00
Tian Tao b9747fdf0c vhost_vdpa: Fix duplicate included kernel.h
linux/kernel.h is included more than once, Remove the one that isn't
necessary.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1600131102-24672-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-10-21 10:34:11 -04:00
Si-Wei Liu 7ed9e3d97c vhost-vdpa: fix page pinning leakage in error path
Pinned pages are not properly accounted particularly when
mapping error occurs on IOTLB update. Clean up dangling
pinned pages for the error path. As the inflight pinned
pages, specifically for memory region that strides across
multiple chunks, would need more than one free page for
book keeping and accounting. For simplicity, pin pages
for all memory in the IOVA range in one go rather than
have multiple pin_user_pages calls to make up the entire
region. This way it's easier to track and account the
pages already mapped, particularly for clean-up in the
error path.

Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Link: https://lore.kernel.org/r/1601701330-16837-3-git-send-email-si-wei.liu@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-10-04 03:47:02 -04:00
Si-Wei Liu 1477c8aebb vhost-vdpa: fix vhost_vdpa_map() on error condition
vhost_vdpa_map() should remove the iotlb entry just added
if the corresponding mapping fails to set up properly.

Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Link: https://lore.kernel.org/r/1601701330-16837-2-git-send-email-si-wei.liu@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-10-04 03:47:02 -04:00
Mike Christie 37787e9f81 vhost vdpa: fix vhost_vdpa_open error handling
We must free the vqs array in the open failure path, because
vhost_vdpa_release will not be called.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/1600712588-9514-2-git-send-email-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-09-30 11:25:06 -04:00
Jason Wang a127c5bbb6 vhost-vdpa: fix backend feature ioctls
Commit 653055b9ac ("vhost-vdpa: support get/set backend features")
introduces two malfunction backend features ioctls:

1) the ioctls was blindly added to vring ioctl instead of vdpa device
   ioctl
2) vhost_set_backend_features() was called when dev mutex has already
   been held which will lead a deadlock

This patch fixes the above issues.

Cc: Eli Cohen <elic@nvidia.com>
Reported-by: Zhu Lingshan <lingshan.zhu@intel.com>
Fixes: 653055b9ac ("vhost-vdpa: support get/set backend features")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200907104343.31141-1-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-09-24 05:54:36 -04:00
Eli Cohen 23750e39d5 vdpa: Modify get_vq_state() to return error code
Modify get_vq_state() so it returns an error code. In case of hardware
acceleration, the available index may be retrieved from the device, an
operation that can possibly fail.

Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Eli Cohen <eli@mellanox.com>
Link: https://lore.kernel.org/r/20200804162048.22587-9-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-08-05 19:00:23 -04:00
Eli Cohen aac50c0bd4 net/vdpa: Use struct for set/get vq state
For now VQ state involves 16 bit available index value encoded in u64
variable. In the future it will be extended to contain more fields. Use
struct to contain the state, now containing only a single u16 for the
available index. In the future we can add fields to this struct.

Reviewed-by: Parav Pandit <parav@mellanox.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eli Cohen <eli@mellanox.com>
Link: https://lore.kernel.org/r/20200804162048.22587-8-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 18:39:19 -04:00
Max Gurtovoy a9974489b6 vdpa: remove hard coded virtq num
This will enable vdpa providers to add support for multi queue feature
and publish it to upper layers (vhost and virtio).

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200804162048.22587-7-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 18:39:18 -04:00
Jason Wang 25abc060d2 vhost-vdpa: support IOTLB batching hints
This patches extend the vhost IOTLB API to accept batch updating hints
form userspace. When userspace wants update the device IOTLB in a
batch, it may do:

1) Write vhost_iotlb_msg with VHOST_IOTLB_BATCH_BEGIN flag
2) Perform a batch of IOTLB updating via VHOST_IOTLB_UPDATE/INVALIDATE
3) Write vhost_iotlb_msg with VHOST_IOTLB_BATCH_END flag

Vhost-vdpa may decide to batch the IOMMU/IOTLB updating in step 3 when
vDPA device support set_map() ops. This is useful for the vDPA device
that want to know all the mappings to tweak their own DMA translation
logic.

For vDPA device that doesn't require set_map(), no behavior changes.

This capability is advertised via VHOST_BACKEND_F_IOTLB_BATCH capability.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200804162048.22587-5-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 18:39:18 -04:00
Jason Wang 653055b9ac vhost-vdpa: support get/set backend features
This patch makes userspace can get and set backend features to
vhost-vdpa.

Signed-off-by: Cindy Lu <lulu@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200804162048.22587-4-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 18:39:18 -04:00
Jason Wang b0bd82bf72 vhost-vdpa: refine ioctl pre-processing
Switch to use 'switch' to make the codes more easier to be extended.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200804162048.22587-2-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 18:39:17 -04:00
Zhu Lingshan 4c05433bc6 vDPA: dont change vq irq after DRIVER_OK
IRQ of a vq is not expected to be changed in a DRIVER_OK ~ !DRIVER_OK
period for irq offloading purposes. Place this comment at the side of
bus ops get_vq_irq than in set_status in vhost_vdpa.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20200804102123.69978-1-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:42 -04:00
Zhu Lingshan 2cf1ba9a4d vhost_vdpa: implement IRQ offloading in vhost_vdpa
This patch introduce a set of functions for setup/unsetup
and update irq offloading respectively by register/unregister
and re-register the irq_bypass_producer.

With these functions, this commit can setup/unsetup
irq offloading through setting DRIVER_OK/!DRIVER_OK, and
update irq offloading through SET_VRING_CALL.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-5-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:42 -04:00
Zhu Lingshan 265a0ad873 vhost: introduce vhost_vring_call
This commit introduces struct vhost_vring_call which replaced
raw struct eventfd_ctx *call_ctx in struct vhost_virtqueue.
Besides eventfd_ctx, it contains a spin lock and an
irq_bypass_producer in its structure.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-2-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:42 -04:00
Jason Wang 6234f80574 vhost: vdpa: remove per device feature whitelist
We used to have a per device feature whitelist to filter out the
unsupported virtio features. But this seems unnecessary since:

- the main idea behind feature whitelist is to block control vq
  feature until we finalize the control virtqueue API. But the current
  vhost-vDPA uAPI is sufficient to support control virtqueue. For
  device that has hardware control virtqueue, the vDPA device driver
  can just setup the hardware virtqueue and let userspace to use
  hardware virtqueue directly. For device that doesn't have a control
  virtqueue, the vDPA device driver need to use e.g vringh to emulate
  a software control virtqueue.
- we don't do it in virtio-vDPA driver

So remove this limitation.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200720085043.16485-1-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin 0d234007a5 vhost/vdpa: switch to new helpers
For new helpers handling legacy features to be effective,
vhost needs to invoke them. Tie them in.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:40 -04:00
Michael S. Tsirkin 321bd21261 virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM
Rename the bit to match latest virtio spec.
Add a compat macro to avoid breaking existing userspace.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-08-03 16:11:42 -04:00
Dan Carpenter c09cc2c319 vhost_vdpa: Fix potential underflow in vhost_vdpa_mmap()
The "vma->vm_pgoff" variable is an unsigned long so if it's larger than
INT_MAX then "index" can be negative leading to an underflow.  Fix this
by changing the type of "index" to "unsigned long".

Fixes: ddd89d0a05 ("vhost_vdpa: support doorbell mapping via mmap")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200610085852.GB5439@mwanda
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:21 -04:00
Linus Torvalds 09102704c6 virtio: features, fixes
virtio-mem
 doorbell mapping for vdpa
 config interrupt support in ifc
 fixes all over the place
 
 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-mem: paravirtualized memory hotplug

 - support doorbell mapping for vdpa

 - config interrupt support in ifc

 - fixes all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (40 commits)
  vhost/test: fix up after API change
  virtio_mem: convert device block size into 64bit
  virtio-mem: drop unnecessary initialization
  ifcvf: implement config interrupt in IFCVF
  vhost: replace -1 with VHOST_FILE_UNBIND in ioctls
  vhost_vdpa: Support config interrupt in vdpa
  ifcvf: ignore continuous setting same status value
  virtio-mem: Don't rely on implicit compiler padding for requests
  virtio-mem: Try to unplug the complete online memory block first
  virtio-mem: Use -ETXTBSY as error code if the device is busy
  virtio-mem: Unplug subblocks right-to-left
  virtio-mem: Drop manual check for already present memory
  virtio-mem: Add parent resource for all added "System RAM"
  virtio-mem: Better retry handling
  virtio-mem: Offline and remove completely unplugged memory blocks
  mm/memory_hotplug: Introduce offline_and_remove_memory()
  virtio-mem: Allow to offline partially unplugged memory blocks
  mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINE
  virtio-mem: Paravirtualized memory hotunplug part 2
  virtio-mem: Paravirtualized memory hotunplug part 1
  ...
2020-06-10 13:42:09 -07:00
Michel Lespinasse d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Zhu Lingshan 776f395004 vhost_vdpa: Support config interrupt in vdpa
This commit implements config interrupt support in
vhost_vdpa layer.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/1591352835-22441-4-git-send-email-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-06 16:26:27 -04:00
Michael S. Tsirkin 4b4e4867d9 vhost_vdpa: disable doorbell mapping for !MMU
There could be ways to support doorbell mapping with !MMU, but things
like pgprot_noncached are not universally supported.
Fixable, but just disable this for now.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:51 -04:00
Jason Wang ddd89d0a05 vhost_vdpa: support doorbell mapping via mmap
Currently the doorbell is relayed via eventfd which may have
significant overhead because of the cost of vmexits or syscall. This
patch introduces mmap() based doorbell mapping which can eliminate the
overhead caused by vmexit or syscall.

To ease the userspace modeling of the doorbell layout (usually
virtio-pci), this patch starts from a doorbell per page
model. Vhost-vdpa only support the hardware doorbell that sit at the
boundary of a page and does not share the page with other registers.

Doorbell of each virtqueue must be mapped separately, pgoff is the
index of the virtqueue. This allows userspace to map a subset of the
doorbell which may be useful for the implementation of software
assisted virtqueue (control vq) in the future.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200529080303.15449-5-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:51 -04:00
Jason Wang 01fcb1cbc8 vhost: allow device that does not depend on vhost worker
vDPA device currently relays the eventfd via vhost worker. This is
inefficient due the latency of wakeup and scheduling, so this patch
tries to introduce a use_worker attribute for the vhost device. When
use_worker is not set with vhost_dev_init(), vhost won't try to
allocate a worker thread and the vhost_poll will be processed directly
in the wakeup function.

This help for vDPA since it reduces the latency caused by vhost worker.

In my testing, it saves 0.2 ms in pings between VMs on a mutual host.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200529080303.15449-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:51 -04:00
Jason Yan e373f3d78d vhost: remove set but not used variable 'status'
Fix the following gcc warning:
drivers/vhost/vdpa.c:299:5: warning: variable 'status' set but not used [-Wunused-but-set-variable]
  u8 status;
     ^~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200402065106.20108-1-yanaijie@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-16 18:31:03 -04:00
Gustavo A. R. Silva aa21c2e73e vhost: vdpa: remove unnecessary null check
container_of is never null, so this null check is
unnecessary.

Addresses-Coverity-ID: 1492006 ("Logically dead code")
Fixes: 20453a45fb06 ("vhost: introduce vDPA-based backend")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200330235040.GA9997@embeddedor
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-16 18:31:02 -04:00
Tiwei Bie 4c8cf31885 vhost: introduce vDPA-based backend
This patch introduces a vDPA-based vhost backend. This backend is
built on top of the same interface defined in virtio-vDPA and provides
a generic vhost interface for userspace to accelerate the virtio
devices in guest.

This backend is implemented as a vDPA device driver on top of the same
ops used in virtio-vDPA. It will create char device entry named
vhost-vdpa-$index for userspace to use. Userspace can use vhost ioctls
on top of this char device to setup the backend.

Vhost ioctls are extended to make it type agnostic and behave like a
virtio device, this help to eliminate type specific API like what
vhost_net/scsi/vsock did:

- VHOST_VDPA_GET_DEVICE_ID: get the virtio device ID which is defined
  by virtio specification to differ from different type of devices
- VHOST_VDPA_GET_VRING_NUM: get the maximum size of virtqueue
  supported by the vDPA device
- VHSOT_VDPA_SET/GET_STATUS: set and get virtio status of vDPA device
- VHOST_VDPA_SET/GET_CONFIG: access virtio config space
- VHOST_VDPA_SET_VRING_ENABLE: enable a specific virtqueue

For memory mapping, IOTLB API is mandated for vhost-vDPA which means
userspace drivers are required to use
VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE to add or remove mapping for
a specific userspace memory region.

The vhost-vDPA API is designed to be type agnostic, but it allows net
device only in current stage. Due to the lacking of control virtqueue
support, some features were filter out by vhost-vdpa.

We will enable more features and devices in the near future.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-8-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00