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- Yosry has also eliminated cgroup's atomic rstat flushing.
- Nhat Pham adds the new cachestat() syscall. It provides userspace
with the ability to query pagecache status - a similar concept to
mincore() but more powerful and with improved usability.
- Mel Gorman provides more optimizations for compaction, reducing the
prevalence of page rescanning.
- Lorenzo Stoakes has done some maintanance work on the get_user_pages()
interface.
- Liam Howlett continues with cleanups and maintenance work to the maple
tree code. Peng Zhang also does some work on maple tree.
- Johannes Weiner has done some cleanup work on the compaction code.
- David Hildenbrand has contributed additional selftests for
get_user_pages().
- Thomas Gleixner has contributed some maintenance and optimization work
for the vmalloc code.
- Baolin Wang has provided some compaction cleanups,
- SeongJae Park continues maintenance work on the DAMON code.
- Huang Ying has done some maintenance on the swap code's usage of
device refcounting.
- Christoph Hellwig has some cleanups for the filemap/directio code.
- Ryan Roberts provides two patch series which yield some
rationalization of the kernel's access to pte entries - use the provided
APIs rather than open-coding accesses.
- Lorenzo Stoakes has some fixes to the interaction between pagecache
and directio access to file mappings.
- John Hubbard has a series of fixes to the MM selftesting code.
- ZhangPeng continues the folio conversion campaign.
- Hugh Dickins has been working on the pagetable handling code, mainly
with a view to reducing the load on the mmap_lock.
- Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from
128 to 8.
- Domenico Cerasuolo has improved the zswap reclaim mechanism by
reorganizing the LRU management.
- Matthew Wilcox provides some fixups to make gfs2 work better with the
buffer_head code.
- Vishal Moola also has done some folio conversion work.
- Matthew Wilcox has removed the remnants of the pagevec code - their
functionality is migrated over to struct folio_batch.
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Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
- Yosry Ahmed brought back some cgroup v1 stats in OOM logs
- Yosry has also eliminated cgroup's atomic rstat flushing
- Nhat Pham adds the new cachestat() syscall. It provides userspace
with the ability to query pagecache status - a similar concept to
mincore() but more powerful and with improved usability
- Mel Gorman provides more optimizations for compaction, reducing the
prevalence of page rescanning
- Lorenzo Stoakes has done some maintanance work on the
get_user_pages() interface
- Liam Howlett continues with cleanups and maintenance work to the
maple tree code. Peng Zhang also does some work on maple tree
- Johannes Weiner has done some cleanup work on the compaction code
- David Hildenbrand has contributed additional selftests for
get_user_pages()
- Thomas Gleixner has contributed some maintenance and optimization
work for the vmalloc code
- Baolin Wang has provided some compaction cleanups,
- SeongJae Park continues maintenance work on the DAMON code
- Huang Ying has done some maintenance on the swap code's usage of
device refcounting
- Christoph Hellwig has some cleanups for the filemap/directio code
- Ryan Roberts provides two patch series which yield some
rationalization of the kernel's access to pte entries - use the
provided APIs rather than open-coding accesses
- Lorenzo Stoakes has some fixes to the interaction between pagecache
and directio access to file mappings
- John Hubbard has a series of fixes to the MM selftesting code
- ZhangPeng continues the folio conversion campaign
- Hugh Dickins has been working on the pagetable handling code, mainly
with a view to reducing the load on the mmap_lock
- Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
from 128 to 8
- Domenico Cerasuolo has improved the zswap reclaim mechanism by
reorganizing the LRU management
- Matthew Wilcox provides some fixups to make gfs2 work better with the
buffer_head code
- Vishal Moola also has done some folio conversion work
- Matthew Wilcox has removed the remnants of the pagevec code - their
functionality is migrated over to struct folio_batch
* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
mm/hugetlb: remove hugetlb_set_page_subpool()
mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
hugetlb: revert use of page_cache_next_miss()
Revert "page cache: fix page_cache_next/prev_miss off by one"
mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
mm: memcg: rename and document global_reclaim()
mm: kill [add|del]_page_to_lru_list()
mm: compaction: convert to use a folio in isolate_migratepages_block()
mm: zswap: fix double invalidate with exclusive loads
mm: remove unnecessary pagevec includes
mm: remove references to pagevec
mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
mm: remove struct pagevec
net: convert sunrpc from pagevec to folio_batch
i915: convert i915_gpu_error to use a folio_batch
pagevec: rename fbatch_count()
mm: remove check_move_unevictable_pages()
drm: convert drm_gem_put_pages() to use a folio_batch
i915: convert shmem_sg_free_table() to use a folio_batch
scatterlist: add sg_set_folio()
...
We are now in a position where no caller of pin_user_pages() requires the
vmas parameter at all, so eliminate this parameter from the function and
all callers.
This clears the way to removing the vmas parameter from GUP altogether.
Link: https://lkml.kernel.org/r/195a99ae949c9f5cb589d2222b736ced96ec199a.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> [qib]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> [drivers/media]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the right structs for PACKED or split vqs when setting and
getting the vring base.
Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Message-Id: <20230424225031.18947-4-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
As is done in the net, iscsi, and vsock vhost support, let the vdpa vqs
know about the features that have been negotiated. This allows vhost
to more safely make decisions based on the features, such as when using
PACKED vs split queues.
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230424225031.18947-2-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
reduction in interrupt rate in virtio
perf improvement for VDUSE
scalability for vhost-scsi
non power of 2 ring support for packed rings
better management for mlx5 vdpa
suspend for snet
VIRTIO_F_NOTIFICATION_DATA
shared backend with vdpa-sim-blk
user VA support in vdpa-sim
better struct packing for virtio
fixes, cleanups 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,vhost,vdpa: features, fixes, and cleanups:
- reduction in interrupt rate in virtio
- perf improvement for VDUSE
- scalability for vhost-scsi
- non power of 2 ring support for packed rings
- better management for mlx5 vdpa
- suspend for snet
- VIRTIO_F_NOTIFICATION_DATA
- shared backend with vdpa-sim-blk
- user VA support in vdpa-sim
- better struct packing for virtio
and fixes, cleanups all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (52 commits)
vhost_vdpa: fix unmap process in no-batch mode
MAINTAINERS: make me a reviewer of VIRTIO CORE AND NET DRIVERS
tools/virtio: fix build caused by virtio_ring changes
virtio_ring: add a struct device forward declaration
vdpa_sim_blk: support shared backend
vdpa_sim: move buffer allocation in the devices
vdpa/snet: use likely/unlikely macros in hot functions
vdpa/snet: implement kick_vq_with_data callback
virtio-vdpa: add VIRTIO_F_NOTIFICATION_DATA feature support
virtio: add VIRTIO_F_NOTIFICATION_DATA feature support
vdpa/snet: support the suspend vDPA callback
vdpa/snet: support getting and setting VQ state
MAINTAINERS: add vringh.h to Virtio Core and Net Drivers
vringh: address kdoc warnings
vdpa: address kdoc warnings
virtio_ring: don't update event idx on get_buf
vdpa_sim: add support for user VA
vdpa_sim: replace the spinlock with a mutex to protect the state
vdpa_sim: use kthread worker
vdpa_sim: make devices agnostic for work management
...
While using the vdpa device with vIOMMU enabled
in the guest VM, when the vdpa device bind to vfio-pci and run testpmd
then system will fail to unmap.
The test process is
Load guest VM --> attach to virtio driver--> bind to vfio-pci driver
So the mapping process is
1)batched mode map to normal MR
2)batched mode unmapped the normal MR
3)unmapped all the memory
4)mapped to iommu MR
This error happened in step 3). The iotlb was freed in step 2)
and the function vhost_vdpa_process_iotlb_msg will return fail
Which causes failure.
To fix this, we will not remove the AS while the iotlb->nmaps is 0.
This will free in the vhost_vdpa_clean
Cc: stable@vger.kernel.org
Fixes: aaca8373c4 ("vhost-vdpa: support ASID based IOTLB API")
Signed-off-by: Cindy Lu <lulu@redhat.com>
Message-Id: <20230420151734.860168-1-lulu@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When the user call VHOST_SET_OWNER ioctl and the vDPA device
has `use_va` set to true, let's call the bind_mm callback.
In this way we can bind the device to the user address space
and directly use the user VA.
The unbind_mm callback is called during the release after
stopping the device.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230404131326.44403-3-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add eventfd for the vdpa callback so that user
can signal it directly instead of triggering the
callback. It will be used for vhost-vdpa case.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Message-Id: <20230323053043.35-9-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
We need the fixes in here for testing, as well as the driver core
changes for documentation updates to build on.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently vhost_vdpa_cleanup() unmaps the DMA mappings by calling
`iommu_unmap(v->domain, map->start, map->size);`
from vhost_vdpa_general_unmap() when the parent vDPA driver doesn't
provide DMA config operations.
However, the IOMMU domain referred to by `v->domain` is freed in
vhost_vdpa_free_domain() before vhost_vdpa_cleanup() in
vhost_vdpa_release() which results in NULL pointer de-reference.
Accordingly, moving the call to vhost_vdpa_free_domain() in
vhost_vdpa_cleanup() would makes sense. This will also help
detaching the dma device in error handling of vhost_vdpa_alloc_domain().
This issue was observed on terminating QEMU with SIGQUIT.
Fixes: 037d430556 ("vhost-vdpa: call vhost_vdpa_cleanup during the release")
Signed-off-by: Gautam Dawar <gautam.dawar@amd.com>
Message-Id: <20230301163203.29883-1-gautam.dawar@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
device feature provisioning in ifcvf, mlx5
new SolidNET driver
support for zoned block device in virtio blk
numa support in virtio pmem
VIRTIO_F_RING_RESET support in vhost-net
more debugfs entries in mlx5
resume support in vdpa
completion batching in virtio blk
cleanup of dma api use in vdpa
now simulating more features in vdpa-sim
documentation, features, 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:
- device feature provisioning in ifcvf, mlx5
- new SolidNET driver
- support for zoned block device in virtio blk
- numa support in virtio pmem
- VIRTIO_F_RING_RESET support in vhost-net
- more debugfs entries in mlx5
- resume support in vdpa
- completion batching in virtio blk
- cleanup of dma api use in vdpa
- now simulating more features in vdpa-sim
- documentation, features, fixes all over the place
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (64 commits)
vdpa/mlx5: support device features provisioning
vdpa/mlx5: make MTU/STATUS presence conditional on feature bits
vdpa: validate device feature provisioning against supported class
vdpa: validate provisioned device features against specified attribute
vdpa: conditionally read STATUS in config space
vdpa: fix improper error message when adding vdpa dev
vdpa/mlx5: Initialize CVQ iotlb spinlock
vdpa/mlx5: Don't clear mr struct on destroy MR
vdpa/mlx5: Directly assign memory key
tools/virtio: enable to build with retpoline
vringh: fix a typo in comments for vringh_kiov
vhost-vdpa: print warning when vhost_vdpa_alloc_domain fails
scsi: virtio_scsi: fix handling of kmalloc failure
vdpa: Fix a couple of spelling mistakes in some messages
vhost-net: support VIRTIO_F_RING_RESET
vhost-scsi: convert sysfs snprintf and sprintf to sysfs_emit
vdpa: mlx5: support per virtqueue dma device
vdpa: set dma mask for vDPA device
virtio-vdpa: support per vq dma device
vdpa: introduce get_vq_dma_device()
...
Including:
- Consolidate iommu_map/unmap functions. There have been
blocking and atomic variants so far, but that was problematic
as this approach does not scale with required new variants
which just differ in the GFP flags used.
So Jason consolidated this back into single functions that
take a GFP parameter. This has the potential to cause
conflicts with other trees, as they introduce new call-sites
for the changed functions. I offered them to pull in the
branch containing these changes and resolve it, but I am not
sure everyone did that. The conflicts this caused with
upstream up to v6.2-rc8 are resolved in the final merge
commit.
- Retire the detach_dev() call-back in iommu_ops
- Arm SMMU updates from Will:
- Device-tree binding updates:
* Cater for three power domains on SM6375
* Document existing compatible strings for Qualcomm SoCs
* Tighten up clocks description for platform-specific compatible strings
- Enable Qualcomm workarounds for some additional platforms that need them
- Intel VT-d updates from Lu Baolu:
- Add Intel IOMMU performance monitoring support
- Set No Execute Enable bit in PASID table entry
- Two performance optimizations
- Fix PASID directory pointer coherency
- Fix missed rollbacks in error path
- Cleanups
- Apple t8110 DART support
- Exynos IOMMU:
- Implement better fault handling
- Error handling fixes
- Renesas IPMMU:
- Add device tree bindings for r8a779g0
- AMD IOMMU:
- Various fixes for handling on SNP-enabled systems and
handling of faults with unknown request-ids
- Cleanups and other small fixes
- Various other smaller fixes and cleanups
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Merge tag 'iommu-updates-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
- Consolidate iommu_map/unmap functions.
There have been blocking and atomic variants so far, but that was
problematic as this approach does not scale with required new
variants which just differ in the GFP flags used. So Jason
consolidated this back into single functions that take a GFP
parameter.
- Retire the detach_dev() call-back in iommu_ops
- Arm SMMU updates from Will:
- Device-tree binding updates:
- Cater for three power domains on SM6375
- Document existing compatible strings for Qualcomm SoCs
- Tighten up clocks description for platform-specific
compatible strings
- Enable Qualcomm workarounds for some additional platforms that
need them
- Intel VT-d updates from Lu Baolu:
- Add Intel IOMMU performance monitoring support
- Set No Execute Enable bit in PASID table entry
- Two performance optimizations
- Fix PASID directory pointer coherency
- Fix missed rollbacks in error path
- Cleanups
- Apple t8110 DART support
- Exynos IOMMU:
- Implement better fault handling
- Error handling fixes
- Renesas IPMMU:
- Add device tree bindings for r8a779g0
- AMD IOMMU:
- Various fixes for handling on SNP-enabled systems and
handling of faults with unknown request-ids
- Cleanups and other small fixes
- Various other smaller fixes and cleanups
* tag 'iommu-updates-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (71 commits)
iommu/amd: Skip attach device domain is same as new domain
iommu: Attach device group to old domain in error path
iommu/vt-d: Allow to use flush-queue when first level is default
iommu/vt-d: Fix PASID directory pointer coherency
iommu/vt-d: Avoid superfluous IOTLB tracking in lazy mode
iommu/vt-d: Fix error handling in sva enable/disable paths
iommu/amd: Improve page fault error reporting
iommu/amd: Do not identity map v2 capable device when snp is enabled
iommu: Fix error unwind in iommu_group_alloc()
iommu/of: mark an unused function as __maybe_unused
iommu: dart: DART_T8110_ERROR range should be 0 to 5
iommu/vt-d: Enable IOMMU perfmon support
iommu/vt-d: Add IOMMU perfmon overflow handler support
iommu/vt-d: Support cpumask for IOMMU perfmon
iommu/vt-d: Add IOMMU perfmon support
iommu/vt-d: Support Enhanced Command Interface
iommu/vt-d: Retrieve IOMMU perfmon capability information
iommu/vt-d: Support size of the register set in DRHD
iommu/vt-d: Set No Execute Enable bit in PASID table entry
iommu/vt-d: Remove sva from intel_svm_dev
...
Add a print explaining why vhost_vdpa_alloc_domain failed if the device
is not IOMMU cache coherent capable.
Without this print, we have no hint why the operation failed.
For example:
$ virsh start <domain>
error: Failed to start domain <domain>
error: Unable to open '/dev/vhost-vdpa-<idx>' for vdpa device:
Unknown error 524
Suggested-by: Eugenio Perez Martin <eperezma@redhat.com>
Signed-off-by: Alvaro Karsz <alvaro.karsz@solid-run.com>
Message-Id: <20230202084212.1328530-1-alvaro.karsz@solid-run.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eugenio Pérez Martin <eperezma@redhat.com>
This new ioctl adds support for resuming the device from userspace.
This is required when trying to restore the device in a functioning
state after it's been suspended. It is already possible to reset a
suspended device, but that means the device must be reconfigured and
all the IOMMU/IOTLB mappings must be recreated. This new operation
allows the device to be resumed without going through a full reset.
This is particularly useful when trying to perform offline migration of
a virtual machine (also known as snapshot/restore) as it allows the VMM
to resume the virtual machine back to a running state after the snapshot
is performed.
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Message-Id: <73b75fb87d25cff59768b4955a81fe7ffe5b4770.1672742878.git.sebastien.boeuf@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Userspace knows if the device can be resumed or not by checking this
feature bit.
It's only exposed if the vdpa driver backend implements the resume()
operation callback. Userspace trying to negotiate this feature when it
hasn't been exposed will result in an error.
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Message-Id: <b18db236ba3d990cdb41278eb4703be9201d9514.1672742878.git.sebastien.boeuf@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Replace direct modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma locking
correctness.
[akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo]
Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minchan Kim <minchan@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Oskolkov <posk@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Punit Agrawal <punit.agrawal@bytedance.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The internal mechanisms support this, but instead of exposting the gfp to
the caller it wrappers it into iommu_map() and iommu_map_atomic()
Fix this instead of adding more variants for GFP_KERNEL_ACCOUNT.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/1-v3-76b587fe28df+6e3-iommu_map_gfp_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Before commit 3d56987938 ("vhost-vdpa: introduce asid based IOTLB")
we called vhost_vdpa_iotlb_unmap(v, iotlb, 0ULL, 0ULL - 1) during
release to free all the resources allocated when processing user IOTLB
messages through vhost_vdpa_process_iotlb_update().
That commit changed the handling of IOTLB a bit, and we accidentally
removed some code called during the release.
We partially fixed this with commit 037d430556 ("vhost-vdpa: call
vhost_vdpa_cleanup during the release") but a potential memory leak is
still there as showed by kmemleak if the application does not send
VHOST_IOTLB_INVALIDATE or crashes:
unreferenced object 0xffff888007fbaa30 (size 16):
comm "blkio-bench", pid 914, jiffies 4294993521 (age 885.500s)
hex dump (first 16 bytes):
40 73 41 07 80 88 ff ff 00 00 00 00 00 00 00 00 @sA.............
backtrace:
[<0000000087736d2a>] kmem_cache_alloc_trace+0x142/0x1c0
[<0000000060740f50>] vhost_vdpa_process_iotlb_msg+0x68c/0x901 [vhost_vdpa]
[<0000000083e8e205>] vhost_chr_write_iter+0xc0/0x4a0 [vhost]
[<000000008f2f414a>] vhost_vdpa_chr_write_iter+0x18/0x20 [vhost_vdpa]
[<00000000de1cd4a0>] vfs_write+0x216/0x4b0
[<00000000a2850200>] ksys_write+0x71/0xf0
[<00000000de8e720b>] __x64_sys_write+0x19/0x20
[<0000000018b12cbb>] do_syscall_64+0x3f/0x90
[<00000000986ec465>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
Let's fix this calling vhost_vdpa_iotlb_unmap() on the whole range in
vhost_vdpa_remove_as(). We move that call before vhost_dev_cleanup()
since we need a valid v->vdev.mm in vhost_vdpa_pa_unmap().
vhost_iotlb_reset() call can be removed, since vhost_vdpa_iotlb_unmap()
on the whole range removes all the entries.
The kmemleak log reported was observed with a vDPA device that has `use_va`
set to true (e.g. VDUSE). This patch has been tested with both types of
devices.
Fixes: 037d430556 ("vhost-vdpa: call vhost_vdpa_cleanup during the release")
Fixes: 3d56987938 ("vhost-vdpa: introduce asid based IOTLB")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20221109154213.146789-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
The ioctl adds support for suspending the device from userspace.
This is a must before getting virtqueue indexes (base) for live migration,
since the device could modify them after userland gets them. There are
individual ways to perform that action for some devices
(VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
way to perform it for any vhost device (and, in particular, vhost-vdpa).
After a successful return of the ioctl call the device must not process
more virtqueue descriptors. The device can answer to read or writes of
config fields as if it were not suspended. In particular, writing to
"queue_enable" with a value of 1 will not make the device start
processing buffers of the virtqueue.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20220810171512.2343333-4-eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Userland knows if it can suspend the device or not by checking this feature
bit.
It's only offered if the vdpa driver backend implements the suspend()
operation callback, and to offer it or userland to ack it if the backend
does not offer that callback is an error.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20220810171512.2343333-3-eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In function vhost_vdpa_probe(), when code execution fails, we should
call ida_simple_remove() to free ida.
Signed-off-by: Bo Liu <liubo03@inspur.com>
Message-Id: <20220805091254.20026-1-liubo03@inspur.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Use the new interface to check the capability for our device
specifically.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Message-Id: <548e316fa282ce513fabb991a4c4d92258062eb5.1654688822.git.robin.murphy@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Before commit 3d56987938 ("vhost-vdpa: introduce asid based IOTLB")
we call vhost_vdpa_iotlb_free() during the release to clean all regions
mapped in the iotlb.
That commit removed vhost_vdpa_iotlb_free() and added vhost_vdpa_cleanup()
to do some cleanup, including deleting all mappings, but we forgot to call
it in vhost_vdpa_release().
This causes that if an application does not remove all mappings explicitly
(or it crashes), the mappings remain in the iotlb and subsequent
applications may fail if they map the same addresses.
Calling vhost_vdpa_cleanup() also fixes a memory leak since we are not
freeing `v->vdev.vqs` during the release from the same commit.
Since vhost_vdpa_cleanup() calls vhost_dev_cleanup() we can remove its
call from vhost_vdpa_release().
Fixes: 3d56987938 ("vhost-vdpa: introduce asid based IOTLB")
Cc: gautam.dawar@xilinx.com
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20220622151407.51232-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
This patch makes get_vq_group and set_group_asid optional. This is
needed to unbreak the vDPA parent that doesn't support multiple
address spaces.
Cc: Gautam Dawar <gautam.dawar@xilinx.com>
Fixes: aaca8373c4 ("vhost-vdpa: support ASID based IOTLB API")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220609041901.2029-1-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The copy_to_user() function returns the number of bytes remaining to be
copied. However, we need to return a negative error code, -EFAULT, to
the user.
Fixes: 87f4c217413a ("vhost-vdpa: introduce uAPI to get the number of virtqueue groups")
Fixes: e96ef636f154 ("vhost-vdpa: introduce uAPI to get the number of address spaces")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Message-Id: <YotG1vXKXXSayr63@kili>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
This patch extends the vhost-vdpa to support ASID based IOTLB API. The
vhost-vdpa device will allocated multiple IOTLBs for vDPA device that
supports multiple address spaces. The IOTLBs and vDPA device memory
mappings is determined and maintained through ASID.
Note that we still don't support vDPA device with more than one
address spaces that depends on platform IOMMU. This work will be done
by moving the IOMMU logic from vhost-vDPA to vDPA device driver.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-16-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Includes fixup:
vhost-vdpa: Fix some error handling path in vhost_vdpa_process_iotlb_msg()
In the error paths introduced by the original patch, a mutex may be left locked.
Add the correct goto instead of a direct return.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Message-Id: <89ef0ae4c26ac3cfa440c71e97e392dcb328ac1b.1653227924.git.christophe.jaillet@wanadoo.fr>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Follows the vDPA support for associating ASID to a specific virtqueue
group. This patch adds a uAPI to support setting them from userspace.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-15-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Follows the support for virtqueue group in vDPA. This patches
introduces uAPI to get the virtqueue group ID for a specific virtqueue
in vhost-vdpa.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-14-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch introduces the uAPI for getting the number of address
spaces supported by this vDPA device.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-13-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Follows the vDPA support for multiple address spaces, this patch
introduce uAPI for the userspace to know the number of virtqueue
groups supported by the vDPA device.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-12-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch converts the vhost-vDPA device to support multiple IOTLBs
tagged via ASID via hlist. This will be used for supporting multiple
address spaces in the following patches.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-11-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patches allows userspace to send ASID based IOTLB message to
vhost. This idea is to use the reserved u32 field in the existing V2
IOTLB message. Vhost device should advertise this capability via
VHOST_BACKEND_F_IOTLB_ASID backend feature.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-10-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@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>
To ease the implementation of per group ASID support for vDPA
device. This patch switches to use a vhost-vdpa specific IOTLB to
avoid the unnecessary refactoring of the vhost core.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-5-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
To prepare for the ASID support for vhost-vdpa, try to pass IOTLB
object to dma helpers. No functional changes, it's just a preparation
for support multiple IOTLBs.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-4-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
- GET_VQS_COUNT: the count of virtqueues that exposed
Signed-off-by: Longpeng <longpeng2@huawei.com>
Link: https://lore.kernel.org/r/20220315032553.455-4-longpeng2@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Longpeng <<a href="mailto:longpeng2@huawei.com" target="_blank">longpeng2@huawei.com</a>><br>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Change vdpa_device.nvqs and vhost_vdpa.nvqs to use u32
Signed-off-by: Longpeng <longpeng2@huawei.com>
Link: https://lore.kernel.org/r/20220315032553.455-3-longpeng2@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Longpeng <<a href="mailto:longpeng2@huawei.com" target="_blank">longpeng2@huawei.com</a>><br></blockquote><div><br></div><div>Acked-by: Jason Wang <<a href="mailto:jasowang@redhat.com">jasowang@redhat.com</a>></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
- GET_CONFIG_SIZE: return the size of the virtio config space.
The size contains the fields which are conditional on feature
bits.
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Longpeng <longpeng2@huawei.com>
Link: https://lore.kernel.org/r/20220315032553.455-2-longpeng2@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
When irq number is negative(e.g., -EINVAL), the virtqueue
may be disabled or the virtqueues are sharing a device irq.
In such case, we should not setup irq offloading for a virtqueue.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20220222115428.998334-3-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
No functional change introduced. vdpa bus driver such as virtio_vdpa
or vhost_vdpa is not supposed to take care of the locking for core
by its own. The locked API vdpa_set_features should suffice the
bus driver's need.
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/1642206481-30721-2-git-send-email-si-wei.liu@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Call reset using the wrapper function vdpa_reset() to make sure the
operation is serialized with cf_mutex.
This comes to protect from the following possible scenario:
vhost_vdpa_set_status() could call the reset op. Since the call is not
protected by cf_mutex, a netlink thread calling vdpa_dev_config_fill
could get passed the VIRTIO_CONFIG_S_FEATURES_OK check in
vdpa_dev_config_fill() and end up reporting wrong features.
Fixes: 5f6e85953d8f ("vdpa: Read device configuration only if FEATURES_OK")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220111183400.38418-3-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu<si-wei.liu@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Avoid the wrapper holding cf_mutex since it is not protecting anything.
To avoid confusion and unnecessary overhead incurred by it, remove.
Fixes: f489f27bc0ab ("vdpa: Sync calls set/get config/status with cf_mutex")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220111183400.38418-2-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu<si-wei.liu@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Add netlink support to configure the max virtqueue pairs for a device.
At least one pair is required. The maximum is dictated by the device.
Example:
$ vdpa dev add name vdpa-a mgmtdev auxiliary/mlx5_core.sf.1 max_vqp 4
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220105114646.577224-6-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add wrappers to get/set status and protect these operations with
cf_mutex to serialize these operations with respect to get/set config
operations.
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220105114646.577224-4-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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>
The return type of get_config_size is size_t so it makes
sense to change the type of the variable holding its result.
That said, this already got taken care of (differently, and arguably
not as well) by commit 3ed21c1451 ("vdpa: check that offsets are
within bounds").
The added 'c->off > size' test in that commit will be done as an
unsigned comparison on 32-bit (safe due to not being signed).
On a 64-bit platform, it will be done as a signed comparison, but in
that case the comparison will be done in 64-bit, and 'c->off' being an
u32 it will be valid thanks to the extended range (ie both values will
be positive in 64 bits).
So this was a real bug, but it was already addressed and marked for stable.
Signed-off-by: Laura Abbott <labbott@kernel.org>
Reported-by: Luo Likang <luolikang@nsfocus.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
It has no sense to call get_status twice, since we already have a
variable for that.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20211104195833.2089796-1-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
In this function "c->off" is a u32 and "size" is a long. On 64bit systems
if "c->off" is greater than "size" then "size - c->off" is a negative and
we always return -E2BIG. But on 32bit systems the subtraction is type
promoted to a high positive u32 value and basically any "c->len" is
accepted.
Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Reported-by: Xie Yongji <xieyongji@bytedance.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211208103337.GA4047@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
