Commit graph

22 commits

Author SHA1 Message Date
Xie Yongji
b27ee76c74 vduse: Fix NULL pointer dereference on sysfs access
The control device has no drvdata. So we will get a
NULL pointer dereference when accessing control
device's msg_timeout attribute via sysfs:

[ 132.841881][ T3644] BUG: kernel NULL pointer dereference, address: 00000000000000f8
[ 132.850619][ T3644] RIP: 0010:msg_timeout_show (drivers/vdpa/vdpa_user/vduse_dev.c:1271)
[ 132.869447][ T3644] dev_attr_show (drivers/base/core.c:2094)
[ 132.870215][ T3644] sysfs_kf_seq_show (fs/sysfs/file.c:59)
[ 132.871164][ T3644] ? device_remove_bin_file (drivers/base/core.c:2088)
[ 132.872082][ T3644] kernfs_seq_show (fs/kernfs/file.c:164)
[ 132.872838][ T3644] seq_read_iter (fs/seq_file.c:230)
[ 132.873578][ T3644] ? __vmalloc_area_node (mm/vmalloc.c:3041)
[ 132.874532][ T3644] kernfs_fop_read_iter (fs/kernfs/file.c:238)
[ 132.875513][ T3644] __kernel_read (fs/read_write.c:440 (discriminator 1))
[ 132.876319][ T3644] kernel_read (fs/read_write.c:459)
[ 132.877129][ T3644] kernel_read_file (fs/kernel_read_file.c:94)
[ 132.877978][ T3644] kernel_read_file_from_fd (include/linux/file.h:45 fs/kernel_read_file.c:186)
[ 132.879019][ T3644] __do_sys_finit_module (kernel/module.c:4207)
[ 132.879930][ T3644] __ia32_sys_finit_module (kernel/module.c:4189)
[ 132.880930][ T3644] do_int80_syscall_32 (arch/x86/entry/common.c:112 arch/x86/entry/common.c:132)
[ 132.881847][ T3644] entry_INT80_compat (arch/x86/entry/entry_64_compat.S:419)

To fix it, don't create the unneeded attribute for
control device anymore.

Fixes: c8a6153b6c ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Reported-by: kernel test robot <oliver.sang@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Message-Id: <20220426073656.229-1-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-08 08:56:03 -04:00
Gautam Dawar
db9adcbf42 vdpa: multiple address spaces support
This patches introduces the multiple address spaces support for vDPA
device. This idea is to identify a specific address space via an
dedicated identifier - ASID.

During vDPA device allocation, vDPA device driver needs to report the
number of address spaces supported by the device then the DMA mapping
ops of the vDPA device needs to be extended to support ASID.

This helps to isolate the environments for the virtqueue that will not
be assigned directly. E.g in the case of virtio-net, the control
virtqueue will not be assigned directly to guest.

As a start, simply claim 1 virtqueue groups and 1 address spaces for
all vDPA devices. And vhost-vDPA will simply reject the device with
more than 1 virtqueue groups or address spaces.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-7-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:44:27 -04:00
Gautam Dawar
d4821902e4 vdpa: introduce virtqueue groups
This patch introduces virtqueue groups to vDPA device. The virtqueue
group is the minimal set of virtqueues that must share an address
space. And the address space identifier could only be attached to
a specific virtqueue group.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-6-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:44:27 -04:00
Linus Torvalds
34af78c4e6 IOMMU Updates for Linux v5.18
Including:
 
 	- IOMMU Core changes:
 	  - Removal of aux domain related code as it is basically dead
 	    and will be replaced by iommu-fd framework
 	  - Split of iommu_ops to carry domain-specific call-backs
 	    separatly
 	  - Cleanup to remove useless ops->capable implementations
 	  - Improve 32-bit free space estimate in iova allocator
 
 	- Intel VT-d updates:
 	  - Various cleanups of the driver
 	  - Support for ATS of SoC-integrated devices listed in
 	    ACPI/SATC table
 
 	- ARM SMMU updates:
 	  - Fix SMMUv3 soft lockup during continuous stream of events
 	  - Fix error path for Qualcomm SMMU probe()
 	  - Rework SMMU IRQ setup to prepare the ground for PMU support
 	  - Minor cleanups and refactoring
 
 	- AMD IOMMU driver:
 	  - Some minor cleanups and error-handling fixes
 
 	- Rockchip IOMMU driver:
 	  - Use standard driver registration
 
 	- MSM IOMMU driver:
 	  - Minor cleanup and change to standard driver registration
 
 	- Mediatek IOMMU driver:
 	  - Fixes for IOTLB flushing logic
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Merge tag 'iommu-updates-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - IOMMU Core changes:
      - Removal of aux domain related code as it is basically dead and
        will be replaced by iommu-fd framework
      - Split of iommu_ops to carry domain-specific call-backs separatly
      - Cleanup to remove useless ops->capable implementations
      - Improve 32-bit free space estimate in iova allocator

 - Intel VT-d updates:
      - Various cleanups of the driver
      - Support for ATS of SoC-integrated devices listed in ACPI/SATC
        table

 - ARM SMMU updates:
      - Fix SMMUv3 soft lockup during continuous stream of events
      - Fix error path for Qualcomm SMMU probe()
      - Rework SMMU IRQ setup to prepare the ground for PMU support
      - Minor cleanups and refactoring

 - AMD IOMMU driver:
      - Some minor cleanups and error-handling fixes

 - Rockchip IOMMU driver:
      - Use standard driver registration

 - MSM IOMMU driver:
      - Minor cleanup and change to standard driver registration

 - Mediatek IOMMU driver:
      - Fixes for IOTLB flushing logic

* tag 'iommu-updates-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (47 commits)
  iommu/amd: Improve amd_iommu_v2_exit()
  iommu/amd: Remove unused struct fault.devid
  iommu/amd: Clean up function declarations
  iommu/amd: Call memunmap in error path
  iommu/arm-smmu: Account for PMU interrupts
  iommu/vt-d: Enable ATS for the devices in SATC table
  iommu/vt-d: Remove unused function intel_svm_capable()
  iommu/vt-d: Add missing "__init" for rmrr_sanity_check()
  iommu/vt-d: Move intel_iommu_ops to header file
  iommu/vt-d: Fix indentation of goto labels
  iommu/vt-d: Remove unnecessary prototypes
  iommu/vt-d: Remove unnecessary includes
  iommu/vt-d: Remove DEFER_DEVICE_DOMAIN_INFO
  iommu/vt-d: Remove domain and devinfo mempool
  iommu/vt-d: Remove iova_cache_get/put()
  iommu/vt-d: Remove finding domain in dmar_insert_one_dev_info()
  iommu/vt-d: Remove intel_iommu::domains
  iommu/mediatek: Always tlb_flush_all when each PM resume
  iommu/mediatek: Add tlb_lock in tlb_flush_all
  iommu/mediatek: Remove the power status checking in tlb flush all
  ...
2022-03-24 19:48:57 -07:00
Xie Yongji
b9d102dafe vduse: Fix returning wrong type in vduse_domain_alloc_iova()
This fixes the following smatch warnings:

drivers/vdpa/vdpa_user/iova_domain.c:305 vduse_domain_alloc_iova() warn: should 'iova_pfn << shift' be a 64 bit type?

Fixes: 8c773d53fb ("vduse: Implement an MMU-based software IOTLB")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20220121083940.102-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2022-03-04 11:56:34 -05:00
John Garry
32e92d9f6f iommu/iova: Separate out rcache init
Currently the rcache structures are allocated for all IOVA domains, even if
they do not use "fast" alloc+free interface. This is wasteful of memory.

In addition, fails in init_iova_rcaches() are not handled safely, which is
less than ideal.

Make "fast" users call a separate rcache init explicitly, which includes
error checking.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/1643882360-241739-1-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2022-02-14 15:43:15 +01:00
Linus Torvalds
3bf6a9e36e virtio,vdpa,qemu_fw_cfg: features, cleanups, fixes
partial support for < MAX_ORDER - 1 granularity for virtio-mem
 driver_override for vdpa
 sysfs ABI documentation for vdpa
 multiqueue config support for mlx5 vdpa
 
 Misc fixes, cleanups.
 
 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,vdpa,qemu_fw_cfg: features, cleanups, and fixes.

   - partial support for < MAX_ORDER - 1 granularity for virtio-mem

   - driver_override for vdpa

   - sysfs ABI documentation for vdpa

   - multiqueue config support for mlx5 vdpa

   - and misc fixes, cleanups"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (42 commits)
  vdpa/mlx5: Fix tracking of current number of VQs
  vdpa/mlx5: Fix is_index_valid() to refer to features
  vdpa: Protect vdpa reset with cf_mutex
  vdpa: Avoid taking cf_mutex lock on get status
  vdpa/vdpa_sim_net: Report max device capabilities
  vdpa: Use BIT_ULL for bit operations
  vdpa/vdpa_sim: Configure max supported virtqueues
  vdpa/mlx5: Report max device capabilities
  vdpa: Support reporting max device capabilities
  vdpa/mlx5: Restore cur_num_vqs in case of failure in change_num_qps()
  vdpa: Add support for returning device configuration information
  vdpa/mlx5: Support configuring max data virtqueue
  vdpa/mlx5: Fix config_attr_mask assignment
  vdpa: Allow to configure max data virtqueues
  vdpa: Read device configuration only if FEATURES_OK
  vdpa: Sync calls set/get config/status with cf_mutex
  vdpa/mlx5: Distribute RX virtqueues in RQT object
  vdpa: Provide interface to read driver features
  vdpa: clean up get_config_size ret value handling
  virtio_ring: mark ring unused on error
  ...
2022-01-18 10:05:48 +02:00
Eli Cohen
a64917bc2e vdpa: Provide interface to read driver features
Provide an interface to read the negotiated features. This is needed
when building the netlink message in vdpa_dev_net_config_fill().

Also fix the implementation of vdpa_dev_net_config_fill() to use the
negotiated features instead of the device features.

To make APIs clearer, make the following name changes to struct
vdpa_config_ops so they better describe their operations:

get_features -> get_device_features
set_features -> set_driver_features

Finally, add get_driver_features to return the negotiated features and
add implementation to all the upstream drivers.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220105114646.577224-2-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:53 -05:00
Guanjun
b4d80c8dda vduse: moving kvfree into caller
This free action should be moved into caller 'vduse_ioctl' in
concert with the allocation.

No functional change.

Signed-off-by: Guanjun <guanjun@linux.alibaba.com>
Link: https://lore.kernel.org/r/1638780498-55571-1-git-send-email-guanjun@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:52 -05:00
Joerg Roedel
66dc1b791c Merge branches 'arm/smmu', 'virtio', 'x86/amd', 'x86/vt-d' and 'core' into next 2022-01-04 10:33:45 +01:00
John Garry via iommu
972bf252f8 iommu/iova: Move fast alloc size roundup into alloc_iova_fast()
It really is a property of the IOVA rcache code that we need to alloc a
power-of-2 size, so relocate the functionality to resize into
alloc_iova_fast(), rather than the callsites.

Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1638875846-23993-1-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-12-17 09:10:40 +01:00
Dan Carpenter
dc1db0060c vduse: check that offset is within bounds in get_config()
This condition checks "len" but it does not check "offset" and that
could result in an out of bounds read if "offset > dev->config_size".
The problem is that since both variables are unsigned the
"dev->config_size - offset" subtraction would result in a very high
unsigned value.

I think these checks might not be necessary because "len" and "offset"
are supposed to already have been validated using the
vhost_vdpa_config_validate() function.  But I do not know the code
perfectly, and I like to be safe.

Fixes: c8a6153b6c ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211208150956.GA29160@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
2021-12-08 14:53:15 -05:00
Dan Carpenter
ff9f9c6e74 vduse: fix memory corruption in vduse_dev_ioctl()
The "config.offset" comes from the user.  There needs to a check to
prevent it being out of bounds.  The "config.offset" and
"dev->config_size" variables are both type u32.  So if the offset if
out of bounds then the "dev->config_size - config.offset" subtraction
results in a very high u32 value.  The out of bounds offset can result
in memory corruption.

Fixes: c8a6153b6c ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211208103307.GA3778@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
2021-12-08 14:53:15 -05:00
Parav Pandit
d8ca2fa5be vdpa: Enable user to set mac and mtu of vdpa device
$ vdpa dev add name bar mgmtdev vdpasim_net mac 00:11:22:33:44:55 mtu 9000

$ vdpa dev config show
bar: mac 00:11:22:33:44:55 link up link_announce false mtu 9000

$ vdpa dev config show -jp
{
    "config": {
        "bar": {
            "mac": "00:11:22:33:44:55",
            "link ": "up",
            "link_announce ": false,
            "mtu": 9000,
        }
    }
}

Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Acked-by: Jason Wang <jasowang@redhat.com>

Link: https://lore.kernel.org/r/20211026175519.87795-5-parav@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2021-11-01 05:26:49 -04:00
Xie Yongji
0943aacf5a vduse: Fix race condition between resetting and irq injecting
The interrupt might be triggered after a reset since there is
no synchronization between resetting and irq injecting. And it
might break something if the interrupt is delayed until a new
round of device initialization.

Fixes: c8a6153b6c ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210929083050.88-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-10-22 06:49:14 -04:00
Xie Yongji
1394103fd7 vduse: Disallow injecting interrupt before DRIVER_OK is set
The interrupt callback should not be triggered before DRIVER_OK
is set. Otherwise, it might break the virtio device driver.
So let's add a check to avoid the unexpected behavior.

Fixes: c8a6153b6c ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210923075722.98-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-10-22 06:49:14 -04:00
Xie Yongji
7bb5fb2073 vduse: Cleanup the old kernel states after reset failure
We should cleanup the old kernel states e.g. interrupt callback
no matter whether the userspace handle the reset correctly or not
since virtio-vdpa can't handle the reset failure now.

Otherwise, the old state might be used after reset which might
break something, e.g. the old interrupt callback might be triggered
by userspace after reset, which can break the virtio device driver.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210906142158.181-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2021-09-14 18:10:43 -04:00
Dan Carpenter
6243e3c78a vduse: missing error code in vduse_init()
This should return -ENOMEM if alloc_workqueue() fails.  Currently it
returns success.

Fixes: b66219796563 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210907073223.GA18254@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2021-09-14 18:10:42 -04:00
Linus Torvalds
78e709522d virtio,vdpa,vhost: features, fixes
vduse driver supporting blk
 virtio-vsock support for end of record with SEQPACKET
 vdpa: mac and mq support for ifcvf and mlx5
 vdpa: management netlink for ifcvf
 virtio-i2c, gpio dt bindings
 
 misc fixes, cleanups
 
 NB: when merging this with
 b542e383d8 ("eventfd: Make signal recursion protection a task bit")
 from Linus' tree, replace eventfd_signal_count with
 eventfd_signal_allowed, and drop the export of eventfd_wake_count from
 ("eventfd: Export eventfd_wake_count to modules").
 
 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:

 - vduse driver ("vDPA Device in Userspace") supporting emulated virtio
   block devices

 - virtio-vsock support for end of record with SEQPACKET

 - vdpa: mac and mq support for ifcvf and mlx5

 - vdpa: management netlink for ifcvf

 - virtio-i2c, gpio dt bindings

 - misc fixes and cleanups

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (39 commits)
  Documentation: Add documentation for VDUSE
  vduse: Introduce VDUSE - vDPA Device in Userspace
  vduse: Implement an MMU-based software IOTLB
  vdpa: Support transferring virtual addressing during DMA mapping
  vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap()
  vdpa: Add an opaque pointer for vdpa_config_ops.dma_map()
  vhost-iotlb: Add an opaque pointer for vhost IOTLB
  vhost-vdpa: Handle the failure of vdpa_reset()
  vdpa: Add reset callback in vdpa_config_ops
  vdpa: Fix some coding style issues
  file: Export receive_fd() to modules
  eventfd: Export eventfd_wake_count to modules
  iova: Export alloc_iova_fast() and free_iova_fast()
  virtio-blk: remove unneeded "likely" statements
  virtio-balloon: Use virtio_find_vqs() helper
  vdpa: Make use of PFN_PHYS/PFN_UP/PFN_DOWN helper macro
  vsock_test: update message bounds test for MSG_EOR
  af_vsock: rename variables in receive loop
  virtio/vsock: support MSG_EOR bit processing
  vhost/vsock: support MSG_EOR bit processing
  ...
2021-09-11 14:48:42 -07:00
Xie Yongji
7bc7f61897 Documentation: Add documentation for VDUSE
VDUSE (vDPA Device in Userspace) is a framework to support
implementing software-emulated vDPA devices in userspace. This
document is intended to clarify the VDUSE design and usage.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-14-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:58 -04:00
Xie Yongji
c8a6153b6c vduse: Introduce VDUSE - vDPA Device in Userspace
This VDUSE driver enables implementing software-emulated vDPA
devices in userspace. The vDPA device is created by
ioctl(VDUSE_CREATE_DEV) on /dev/vduse/control. Then a char device
interface (/dev/vduse/$NAME) is exported to userspace for device
emulation.

In order to make the device emulation more secure, the device's
control path is handled in kernel. A message mechnism is introduced
to forward some dataplane related control messages to userspace.

And in the data path, the DMA buffer will be mapped into userspace
address space through different ways depending on the vDPA bus to
which the vDPA device is attached. In virtio-vdpa case, the MMU-based
software IOTLB is used to achieve that. And in vhost-vdpa case, the
DMA buffer is reside in a userspace memory region which can be shared
to the VDUSE userspace processs via transferring the shmfd.

For more details on VDUSE design and usage, please see the follow-on
Documentation commit.

NB(mst): when merging this with
b542e383d8 ("eventfd: Make signal recursion protection a task bit")
replace eventfd_signal_count with eventfd_signal_allowed,
and drop the previous
("eventfd: Export eventfd_wake_count to modules").

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-13-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:58 -04:00
Xie Yongji
8c773d53fb vduse: Implement an MMU-based software IOTLB
This implements an MMU-based software IOTLB to support mapping
kernel dma buffer into userspace dynamically. The basic idea
behind it is treating MMU (VA->PA) as IOMMU (IOVA->PA). The
software IOTLB will set up MMU mapping instead of IOMMU mapping
for the DMA transfer so that the userspace process is able to
use its virtual address to access the dma buffer in kernel.

To avoid security issue, a bounce-buffering mechanism is
introduced to prevent userspace accessing the original buffer
directly which may contain other kernel data. During the mapping,
unmapping, the software IOTLB will copy the data from the original
buffer to the bounce buffer and back, depending on the direction
of the transfer. And the bounce-buffer addresses will be mapped
into the user address space instead of the original one.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-12-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 07:20:58 -04:00