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Introduce two APIs: vduse_domain_add_user_bounce_pages()
and vduse_domain_remove_user_bounce_pages() to support
adding and removing userspace pages for bounce buffers.
During adding and removing, the DMA data would be copied
from the kernel bounce pages to the userspace bounce pages
and back.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220803045523.23851-4-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
kmap_atomic() is being deprecated in favor of kmap_local_page().
The use of kmap_atomic() in do_bounce() is all thread local therefore
kmap_local_page() is a sufficient replacement.
Convert to kmap_local_page() but, instead of open coding it,
use the helpers memcpy_to_page() and memcpy_from_page().
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Message-Id: <20220803045523.23851-3-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Now we use domain->iotlb_lock to protect two different
variables: domain->bounce_maps->bounce_page and
domain->iotlb. But for domain->bounce_maps->bounce_page,
we actually don't need any synchronization between
vduse_domain_get_bounce_page() and vduse_domain_free_bounce_pages()
since vduse_domain_get_bounce_page() will only be called in
page fault handler and vduse_domain_free_bounce_pages() will
be called during file release.
So let's remove the unnecessary spin lock protection in
vduse_domain_get_bounce_page(). Then the usage of
domain->iotlb_lock could be more clear: the lock will be
only used to protect the domain->iotlb.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220803045523.23851-2-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vduse devices are not backed by any real devices such as PCI. Hence it
doesn't have any parent device linked to it.
Kernel driver model in [1] suggests to avoid an empty device
release callback.
Hence tie the mgmtdevice object's life cycle to an allocate dummy struct
device instead of static one.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/core-api/kobject.rst?h=v5.18-rc7#n284
Signed-off-by: Parav Pandit <parav@nvidia.com>
Message-Id: <20220613195223.473966-1-parav@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
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>
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>
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
...
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>
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>
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
...
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>
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>
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
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
$ 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>
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>
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>
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>
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>
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
...
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>
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>
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>
