Automatically scaling the depot up to suit the peak capacity of a
workload is all well and good, but it would be nice to have a way to
scale it back down again if the workload changes. To that end, add
backround reclaim that will gradually free surplus magazines if the
depot size remains above a reasonable threshold for long enough.
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/03170665c56d89c6ce6081246b47f68d4e483308.1694535580.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The algorithm in the original paper specifies the storage of full
magazines in the depot as an unbounded list rather than a fixed-size
array. It turns out to be pretty straightforward to do this in our
implementation with no significant loss of efficiency. This allows
the depot to scale up to the working set sizes of larger systems,
while also potentially saving some memory on smaller ones too.
Since this involves touching struct iova_magazine with the requisite
care, we may as well reinforce the comment with a proper assertion too.
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/f597aa72fc3e1d315bc4574af0ce0ebe5c31cd22.1694535580.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Only the member 'size' needs to be initialized to 0. Clearing the array
pfns[], which is about 1 KiB in size, not only wastes time, but also
causes cache pollution.
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20230421072422.869-1-thunder.leizhen@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
In __alloc_and_insert_iova_range, there is an issue that retry_pfn
overflows. The value of iovad->anchor.pfn_hi is ~0UL, then when
iovad->cached_node is iovad->anchor, curr_iova->pfn_hi + 1 will
overflow. As a result, if the retry logic is executed, low_pfn is
updated to 0, and then new_pfn < low_pfn returns false to make the
allocation successful.
This issue occurs in the following two situations:
1. The first iova size exceeds the domain size. When initializing
iova domain, iovad->cached_node is assigned as iovad->anchor. For
example, the iova domain size is 10M, start_pfn is 0x1_F000_0000,
and the iova size allocated for the first time is 11M. The
following is the log information, new->pfn_lo is smaller than
iovad->cached_node.
Example log as follows:
[ 223.798112][T1705487] sh: [name:iova&]__alloc_and_insert_iova_range
start_pfn:0x1f0000,retry_pfn:0x0,size:0xb00,limit_pfn:0x1f0a00
[ 223.799590][T1705487] sh: [name:iova&]__alloc_and_insert_iova_range
success start_pfn:0x1f0000,new->pfn_lo:0x1efe00,new->pfn_hi:0x1f08ff
2. The node with the largest iova->pfn_lo value in the iova domain
is deleted, iovad->cached_node will be updated to iovad->anchor,
and then the alloc iova size exceeds the maximum iova size that can
be allocated in the domain.
After judging that retry_pfn is less than limit_pfn, call retry_pfn+1
to fix the overflow issue.
Signed-off-by: jianjiao zeng <jianjiao.zeng@mediatek.com>
Signed-off-by: Yunfei Wang <yf.wang@mediatek.com>
Cc: <stable@vger.kernel.org> # 5.15.*
Fixes: 4e89dce725 ("iommu/iova: Retry from last rb tree node if iova search fails")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20230111063801.25107-1-yf.wang@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The iovad->rcaches check in iova_rcache_get() is pretty much useless
without the same check in iova_rcache_insert().
Instead of adding this symmetric check to fastpath iova_rcache_insert(),
drop the check in iova_rcache_get() in favour of making the IOVA domain
rcache init more robust to failure in future.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1662557681-145906-4-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Two of the magazine helpers have BUG_ON() checks, as follows:
- iova_magazine_pop() - here we ensure that the mag is not empty. However
we already ensure that in the only caller, __iova_rcache_get().
- iova_magazine_push() - here we ensure that the mag is not full. However
we already ensure that in the only caller, __iova_rcache_insert().
As described, the two bug checks are pointless so drop them.
Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/1662557681-145906-3-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since commit 32e92d9f6f ("iommu/iova: Separate out rcache init") it
has not been possible to have NULL CPU rcache "loaded" or "prev" magazine
pointers once the IOVA domain has been properly initialized. Previously it
was only possible to have NULL pointers from failure to allocate the
magazines in the IOVA domain initialization. The only other two functions
to modify these pointers - __iova_rcache_{get, insert}() - would already
ensure that these pointers were non-NULL if initially non-NULL.
As such, the mag NULL pointer checks in iova_magazine_full(),
iova_magazine_empty(), and iova_magazine_free_pfns() may be dropped.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/1662557681-145906-2-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
- convert arm32 to the common dma-direct code (Arnd Bergmann, Robin Murphy,
Christoph Hellwig)
- restructure the PCIe peer to peer mapping support (Logan Gunthorpe)
- allow the IOMMU code to communicate an optional DMA mapping length
and use that in scsi and libata (John Garry)
- split the global swiotlb lock (Tianyu Lan)
- various fixes and cleanup (Chao Gao, Dan Carpenter, Dongli Zhang,
Lukas Bulwahn, Robin Murphy)
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Merge tag 'dma-mapping-5.20-2022-08-06' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- convert arm32 to the common dma-direct code (Arnd Bergmann, Robin
Murphy, Christoph Hellwig)
- restructure the PCIe peer to peer mapping support (Logan Gunthorpe)
- allow the IOMMU code to communicate an optional DMA mapping length
and use that in scsi and libata (John Garry)
- split the global swiotlb lock (Tianyu Lan)
- various fixes and cleanup (Chao Gao, Dan Carpenter, Dongli Zhang,
Lukas Bulwahn, Robin Murphy)
* tag 'dma-mapping-5.20-2022-08-06' of git://git.infradead.org/users/hch/dma-mapping: (45 commits)
swiotlb: fix passing local variable to debugfs_create_ulong()
dma-mapping: reformat comment to suppress htmldoc warning
PCI/P2PDMA: Remove pci_p2pdma_[un]map_sg()
RDMA/rw: drop pci_p2pdma_[un]map_sg()
RDMA/core: introduce ib_dma_pci_p2p_dma_supported()
nvme-pci: convert to using dma_map_sgtable()
nvme-pci: check DMA ops when indicating support for PCI P2PDMA
iommu/dma: support PCI P2PDMA pages in dma-iommu map_sg
iommu: Explicitly skip bus address marked segments in __iommu_map_sg()
dma-mapping: add flags to dma_map_ops to indicate PCI P2PDMA support
dma-direct: support PCI P2PDMA pages in dma-direct map_sg
dma-mapping: allow EREMOTEIO return code for P2PDMA transfers
PCI/P2PDMA: Introduce helpers for dma_map_sg implementations
PCI/P2PDMA: Attempt to set map_type if it has not been set
lib/scatterlist: add flag for indicating P2PDMA segments in an SGL
swiotlb: clean up some coding style and minor issues
dma-mapping: update comment after dmabounce removal
scsi: sd: Add a comment about limiting max_sectors to shost optimal limit
ata: libata-scsi: cap ata_device->max_sectors according to shost->max_sectors
scsi: scsi_transport_sas: cap shost opt_sectors according to DMA optimal limit
...
Add the IOMMU callback for DMA mapping API dma_opt_mapping_size(), which
allows the drivers to know the optimal mapping limit and thus limit the
requested IOVA lengths.
This value is based on the IOVA rcache range limit, as IOVAs allocated
above this limit must always be newly allocated, which may be quite slow.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
kmalloc will round up the request size to power of 2, and current
iova_magazine's size is 1032 (1024+8) bytes, so each instance
allocated will get 2048 bytes from kmalloc, causing around 1KB
waste.
Change IOVA_MAG_SIZE from 128 to 127 to make size of 'iova_magazine'
1024 bytes so that no memory will be wasted.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20220703114450.15184-1-feng.tang@intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
For various reasons based on the allocator behaviour and typical
use-cases at the time, when the max32_alloc_size optimisation was
introduced it seemed reasonable to couple the reset of the tracked
size to the update of cached32_node upon freeing a relevant IOVA.
However, since subsequent optimisations focused on helping genuine
32-bit devices make best use of even more limited address spaces, it
is now a lot more likely for cached32_node to be anywhere in a "full"
32-bit address space, and as such more likely for space to become
available from IOVAs below that node being freed.
At this point, the short-cut in __cached_rbnode_delete_update() really
doesn't hold up any more, and we need to fix the logic to reliably
provide the expected behaviour. We still want cached32_node to only move
upwards, but we should reset the allocation size if *any* 32-bit space
has become available.
Reported-by: Yunfei Wang <yf.wang@mediatek.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Miles Chen <miles.chen@mediatek.com>
Link: https://lore.kernel.org/r/033815732d83ca73b13c11485ac39336f15c3b40.1646318408.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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>
Complete the move into iommu-dma by refactoring the flush queues
themselves to belong to the DMA cookie rather than the IOVA domain.
The refactoring may as well extend to some minor cosmetic aspects
too, to help us stay one step ahead of the style police.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/24304722005bc6f144e2a1fdd865d1465722fc2e.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Flush queues are specific to DMA ops, which are now handled exclusively
by iommu-dma. As such, now that the historical artefacts from being
shared directly with drivers have been cleaned up, move the flush queue
code into iommu-dma itself to get it out of the way of other IOVA users.
This is pure code movement with no functional change; refactoring to
clean up the headers and definitions will follow.
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1d9a1ee1392e96eaae5e6467181b3e83edfdfbad.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Squash and simplify some of the freeing code, and move the init
and free routines down into the rest of the flush queue code to
obviate the forward declarations.
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/b0dd4565e6646b6489599d7a1eaa362c75f53c95.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
page->freelist is for the use of slab. We already have the ability
to free a list of pages in the core mm, but it requires the use of a
list_head and for the pages to be chained together through page->lru.
Switch the Intel IOMMU and IOVA code over to using free_pages_list().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
[rm: split from original patch, cosmetic tweaks, fix fq entries]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/2115b560d9a0ce7cd4b948bd51a2b7bde8fdfd59.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Once again, with iommu-dma now being the only flush queue user, we no
longer need the extra level of indirection through flush_cb. Squash that
and let the flush queue code call the domain method directly. This does
mean temporarily having to carry an additional copy of the IOMMU domain
pointer around instead, but only until a later patch untangles it again.
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/e3f9b4acdd6640012ef4fbc819ac868d727b64a9.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
All flush queues are driven by iommu-dma now, so there is no need to
abstract entry_dtor or its data any more. Squash the now-canonical
implementation directly into the IOVA code to get it out of the way.
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/2260f8de00ab5e0f9d2a1cf8978e6ae7cd4f182c.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
It turns out to be possible for hotplugging out a device to reach the
stage of tearing down the device's group and default domain before the
domain's flush queue has drained naturally. At this point, it is then
possible for the timeout to expire just before the del_timer() call
in free_iova_flush_queue(), such that we then proceed to free the FQ
resources while fq_flush_timeout() is still accessing them on another
CPU. Crashes due to this have been observed in the wild while removing
NVMe devices.
Close the race window by using del_timer_sync() to safely wait for any
active timeout handler to finish before we start to free things. We
already avoid any locking in free_iova_flush_queue() since the FQ is
supposed to be inactive anyway, so the potential deadlock scenario does
not apply.
Fixes: 9a005a800a ("iommu/iova: Add flush timer")
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
[ rm: rewrite commit message ]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0a365e5b07f14b7344677ad6a9a734966a8422ce.1639753638.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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>
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
...
Export alloc_iova_fast() and free_iova_fast() so that
some modules can make use of the per-CPU cache to get
rid of rbtree spinlock in alloc_iova() and free_iova()
during IOVA allocation.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210831103634.33-2-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Allocating and enabling a flush queue is in fact something we can
reasonably do while a DMA domain is active, without having to rebuild it
from scratch. Thus we can allow a strict -> non-strict transition from
sysfs without requiring to unbind the device's driver, which is of
particular interest to users who want to make selective relaxations to
critical devices like the one serving their root filesystem.
Disabling and draining a queue also seems technically possible to
achieve without rebuilding the whole domain, but would certainly be more
involved. Furthermore there's not such a clear use-case for tightening
up security *after* the device may already have done whatever it is that
you don't trust it not to do, so we only consider the relaxation case.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/d652966348c78457c38bf18daf369272a4ebc2c9.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since iommu_iotlb_gather exists to help drivers optimise flushing for a
given unmap request, it is also the logical place to indicate whether
the unmap is strict or not, and thus help them further optimise for
whether to expect a sync or a flush_all subsequently. As part of that,
it also seems fair to make the flush queue code take responsibility for
enforcing the really subtle ordering requirement it brings, so that we
don't need to worry about forgetting that if new drivers want to add
flush queue support, and can consolidate the existing versions.
While we're adding to the kerneldoc, also fill in some info for
@freelist which was overlooked previously.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/bf5f8e2ad84e48c712ccbf80fa8c610594c7595f.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
It is not necessary to put free_iova_mem() inside of spinlock/unlock
iova_rbtree_lock which only leads to more completion for the spinlock.
It has a small promote on the performance after the change. And also
rename private_free_iova() as remove_iova() because the function will not
free iova after that change.
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1620647582-194621-1-git-send-email-chenxiang66@hisilicon.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Function free_iova_fast() is only referenced by dma-iommu.c, which can
only be in-built, so stop exporting it.
This was missed in an earlier tidy-up patch.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1616675401-151997-5-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Function iommu_dma_free_cpu_cached_iovas() no longer has any caller, so
delete it.
With that, function free_cpu_cached_iovas() may be made static.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1616675401-151997-4-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Like the Intel IOMMU driver already does, flush the per-IOVA domain
CPU rcache when a CPU goes offline - there's no point in keeping it.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1616675401-151997-2-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
When restarting after searching below the cached node fails, resetting
the start point to the anchor node is often overly pessimistic. If
allocations are made with mixed limits - particularly in the case of the
opportunistic 32-bit allocation for PCI devices - this could mean
significant time wasted walking through the whole populated upper range
just to reach the initial limit. We can improve on that by implementing
a proper tree traversal to find the first node above the relevant limit,
and set the exact start point.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/076b3484d1e5057b95d8c387c894bd6ad2514043.1614962123.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The following functions are not referenced outside dma-iommu.c (and
iova.c), which can only be built-in:
- init_iova_flush_queue()
- free_iova_fast()
- queue_iova()
- alloc_iova_fast()
So stop exporting them.
Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/1609940111-28563-4-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since commit c588072bba ("iommu/vt-d: Convert intel iommu driver to the
iommu ops"), function copy_reserved_iova() is not referenced, so delete
it.
Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/1609940111-28563-3-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Both find_iova() and __free_iova() take iova_rbtree_lock,
there is no reason to take and release it twice inside
free_iova().
Fold them into one critical section by calling the unlock
versions instead.
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1605608734-84416-5-git-send-email-john.garry@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
When ever an iova alloc request fails we free the iova
ranges present in the percpu iova rcaches and then retry
but the global iova rcache is not freed as a result we could
still see iova alloc failure even after retry as global
rcache is holding the iova's which can cause fragmentation.
So, free the global iova rcache as well and then go for the
retry.
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: John Garry <john.garry@huaqwei.com>
Link: https://lore.kernel.org/r/1601451864-5956-2-git-send-email-vjitta@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
When ever a new iova alloc request comes iova is always searched
from the cached node and the nodes which are previous to cached
node. So, even if there is free iova space available in the nodes
which are next to the cached node iova allocation can still fail
because of this approach.
Consider the following sequence of iova alloc and frees on
1GB of iova space
1) alloc - 500MB
2) alloc - 12MB
3) alloc - 499MB
4) free - 12MB which was allocated in step 2
5) alloc - 13MB
After the above sequence we will have 12MB of free iova space and
cached node will be pointing to the iova pfn of last alloc of 13MB
which will be the lowest iova pfn of that iova space. Now if we get an
alloc request of 2MB we just search from cached node and then look
for lower iova pfn's for free iova and as they aren't any, iova alloc
fails though there is 12MB of free iova space.
To avoid such iova search failures do a retry from the last rb tree node
when iova search fails, this will search the entire tree and get an iova
if its available.
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1601451864-5956-1-git-send-email-vjitta@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
The performance of the atomic_xchg is better than atomic_cmpxchg because
no comparison is required. While the value of @fq_timer_on can only be 0
or 1. Let's use atomic_xchg instead of atomic_cmpxchg here because we
only need to check that the value changes from 0 to 1 or from 1 to 1.
Signed-off-by: Yuqi Jin <jinyuqi@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Link: https://lore.kernel.org/r/1598517834-30275-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Unlike the other instances which represent a complete loss of
consistency within the rcache mechanism itself, or a fundamental
and obvious misconfiguration by an IOMMU driver, the BUG_ON() in
iova_magazine_free_pfns() can be provoked at more or less any time
in a "spooky action-at-a-distance" manner by any old device driver
passing nonsense to dma_unmap_*() which then propagates through to
queue_iova().
Not only is this well outside the IOVA layer's control, it's also
nowhere near fatal enough to justify panicking anyway - all that
really achieves is to make debugging the offending driver more
difficult. Let's simply WARN and otherwise ignore bogus PFNs.
Reported-by: Prakash Gupta <guptap@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Prakash Gupta <guptap@codeaurora.org>
Link: https://lore.kernel.org/r/acbd2d092b42738a03a21b417ce64e27f8c91c86.1591103298.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
In commit 14bd9a607f ("iommu/iova: Separate atomic variables
to improve performance") Jinyu Qi identified that the atomic_cmpxchg()
in queue_iova() was causing a performance loss and moved critical fields
so that the false sharing would not impact them.
However, avoiding the false sharing in the first place seems easy.
We should attempt the atomic_cmpxchg() no more than 100 times
per second. Adding an atomic_read() will keep the cache
line mostly shared.
This false sharing came with commit 9a005a800a
("iommu/iova: Add flush timer").
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 9a005a800a ('iommu/iova: Add flush timer')
Cc: Jinyu Qi <jinyuqi@huawei.com>
Cc: Joerg Roedel <jroedel@suse.de>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since the cached32_node is allowed to be advanced above dma_32bit_pfn
(to provide a shortcut into the limited range), we need to be careful to
remove the to be freed node if it is the cached32_node.
[ 48.477773] BUG: KASAN: use-after-free in __cached_rbnode_delete_update+0x68/0x110
[ 48.477812] Read of size 8 at addr ffff88870fc19020 by task kworker/u8:1/37
[ 48.477843]
[ 48.477879] CPU: 1 PID: 37 Comm: kworker/u8:1 Tainted: G U 5.2.0+ #735
[ 48.477915] Hardware name: Intel Corporation NUC7i5BNK/NUC7i5BNB, BIOS BNKBL357.86A.0052.2017.0918.1346 09/18/2017
[ 48.478047] Workqueue: i915 __i915_gem_free_work [i915]
[ 48.478075] Call Trace:
[ 48.478111] dump_stack+0x5b/0x90
[ 48.478137] print_address_description+0x67/0x237
[ 48.478178] ? __cached_rbnode_delete_update+0x68/0x110
[ 48.478212] __kasan_report.cold.3+0x1c/0x38
[ 48.478240] ? __cached_rbnode_delete_update+0x68/0x110
[ 48.478280] ? __cached_rbnode_delete_update+0x68/0x110
[ 48.478308] __cached_rbnode_delete_update+0x68/0x110
[ 48.478344] private_free_iova+0x2b/0x60
[ 48.478378] iova_magazine_free_pfns+0x46/0xa0
[ 48.478403] free_iova_fast+0x277/0x340
[ 48.478443] fq_ring_free+0x15a/0x1a0
[ 48.478473] queue_iova+0x19c/0x1f0
[ 48.478597] cleanup_page_dma.isra.64+0x62/0xb0 [i915]
[ 48.478712] __gen8_ppgtt_cleanup+0x63/0x80 [i915]
[ 48.478826] __gen8_ppgtt_cleanup+0x42/0x80 [i915]
[ 48.478940] __gen8_ppgtt_clear+0x433/0x4b0 [i915]
[ 48.479053] __gen8_ppgtt_clear+0x462/0x4b0 [i915]
[ 48.479081] ? __sg_free_table+0x9e/0xf0
[ 48.479116] ? kfree+0x7f/0x150
[ 48.479234] i915_vma_unbind+0x1e2/0x240 [i915]
[ 48.479352] i915_vma_destroy+0x3a/0x280 [i915]
[ 48.479465] __i915_gem_free_objects+0xf0/0x2d0 [i915]
[ 48.479579] __i915_gem_free_work+0x41/0xa0 [i915]
[ 48.479607] process_one_work+0x495/0x710
[ 48.479642] worker_thread+0x4c7/0x6f0
[ 48.479687] ? process_one_work+0x710/0x710
[ 48.479724] kthread+0x1b2/0x1d0
[ 48.479774] ? kthread_create_worker_on_cpu+0xa0/0xa0
[ 48.479820] ret_from_fork+0x1f/0x30
[ 48.479864]
[ 48.479907] Allocated by task 631:
[ 48.479944] save_stack+0x19/0x80
[ 48.479994] __kasan_kmalloc.constprop.6+0xc1/0xd0
[ 48.480038] kmem_cache_alloc+0x91/0xf0
[ 48.480082] alloc_iova+0x2b/0x1e0
[ 48.480125] alloc_iova_fast+0x58/0x376
[ 48.480166] intel_alloc_iova+0x90/0xc0
[ 48.480214] intel_map_sg+0xde/0x1f0
[ 48.480343] i915_gem_gtt_prepare_pages+0xb8/0x170 [i915]
[ 48.480465] huge_get_pages+0x232/0x2b0 [i915]
[ 48.480590] ____i915_gem_object_get_pages+0x40/0xb0 [i915]
[ 48.480712] __i915_gem_object_get_pages+0x90/0xa0 [i915]
[ 48.480834] i915_gem_object_prepare_write+0x2d6/0x330 [i915]
[ 48.480955] create_test_object.isra.54+0x1a9/0x3e0 [i915]
[ 48.481075] igt_shared_ctx_exec+0x365/0x3c0 [i915]
[ 48.481210] __i915_subtests.cold.4+0x30/0x92 [i915]
[ 48.481341] __run_selftests.cold.3+0xa9/0x119 [i915]
[ 48.481466] i915_live_selftests+0x3c/0x70 [i915]
[ 48.481583] i915_pci_probe+0xe7/0x220 [i915]
[ 48.481620] pci_device_probe+0xe0/0x180
[ 48.481665] really_probe+0x163/0x4e0
[ 48.481710] device_driver_attach+0x85/0x90
[ 48.481750] __driver_attach+0xa5/0x180
[ 48.481796] bus_for_each_dev+0xda/0x130
[ 48.481831] bus_add_driver+0x205/0x2e0
[ 48.481882] driver_register+0xca/0x140
[ 48.481927] do_one_initcall+0x6c/0x1af
[ 48.481970] do_init_module+0x106/0x350
[ 48.482010] load_module+0x3d2c/0x3ea0
[ 48.482058] __do_sys_finit_module+0x110/0x180
[ 48.482102] do_syscall_64+0x62/0x1f0
[ 48.482147] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 48.482190]
[ 48.482224] Freed by task 37:
[ 48.482273] save_stack+0x19/0x80
[ 48.482318] __kasan_slab_free+0x12e/0x180
[ 48.482363] kmem_cache_free+0x70/0x140
[ 48.482406] __free_iova+0x1d/0x30
[ 48.482445] fq_ring_free+0x15a/0x1a0
[ 48.482490] queue_iova+0x19c/0x1f0
[ 48.482624] cleanup_page_dma.isra.64+0x62/0xb0 [i915]
[ 48.482749] __gen8_ppgtt_cleanup+0x63/0x80 [i915]
[ 48.482873] __gen8_ppgtt_cleanup+0x42/0x80 [i915]
[ 48.482999] __gen8_ppgtt_clear+0x433/0x4b0 [i915]
[ 48.483123] __gen8_ppgtt_clear+0x462/0x4b0 [i915]
[ 48.483250] i915_vma_unbind+0x1e2/0x240 [i915]
[ 48.483378] i915_vma_destroy+0x3a/0x280 [i915]
[ 48.483500] __i915_gem_free_objects+0xf0/0x2d0 [i915]
[ 48.483622] __i915_gem_free_work+0x41/0xa0 [i915]
[ 48.483659] process_one_work+0x495/0x710
[ 48.483704] worker_thread+0x4c7/0x6f0
[ 48.483748] kthread+0x1b2/0x1d0
[ 48.483787] ret_from_fork+0x1f/0x30
[ 48.483831]
[ 48.483868] The buggy address belongs to the object at ffff88870fc19000
[ 48.483868] which belongs to the cache iommu_iova of size 40
[ 48.483920] The buggy address is located 32 bytes inside of
[ 48.483920] 40-byte region [ffff88870fc19000, ffff88870fc19028)
[ 48.483964] The buggy address belongs to the page:
[ 48.484006] page:ffffea001c3f0600 refcount:1 mapcount:0 mapping:ffff8888181a91c0 index:0x0 compound_mapcount: 0
[ 48.484045] flags: 0x8000000000010200(slab|head)
[ 48.484096] raw: 8000000000010200 ffffea001c421a08 ffffea001c447e88 ffff8888181a91c0
[ 48.484141] raw: 0000000000000000 0000000000120012 00000001ffffffff 0000000000000000
[ 48.484188] page dumped because: kasan: bad access detected
[ 48.484230]
[ 48.484265] Memory state around the buggy address:
[ 48.484314] ffff88870fc18f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 48.484361] ffff88870fc18f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 48.484406] >ffff88870fc19000: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
[ 48.484451] ^
[ 48.484494] ffff88870fc19080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 48.484530] ffff88870fc19100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108602
Fixes: e60aa7b538 ("iommu/iova: Extend rbtree node caching")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: <stable@vger.kernel.org> # v4.15+
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Intel VT-d driver was reworked to use common deferred flushing
implementation. Previously there was one global per-cpu flush queue,
afterwards - one per domain.
Before deferring a flush, the queue should be allocated and initialized.
Currently only domains with IOMMU_DOMAIN_DMA type initialize their flush
queue. It's probably worth to init it for static or unmanaged domains
too, but it may be arguable - I'm leaving it to iommu folks.
Prevent queuing an iova flush if the domain doesn't have a queue.
The defensive check seems to be worth to keep even if queue would be
initialized for all kinds of domains. And is easy backportable.
On 4.19.43 stable kernel it has a user-visible effect: previously for
devices in si domain there were crashes, on sata devices:
BUG: spinlock bad magic on CPU#6, swapper/0/1
lock: 0xffff88844f582008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 6 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #1
Call Trace:
<IRQ>
dump_stack+0x61/0x7e
spin_bug+0x9d/0xa3
do_raw_spin_lock+0x22/0x8e
_raw_spin_lock_irqsave+0x32/0x3a
queue_iova+0x45/0x115
intel_unmap+0x107/0x113
intel_unmap_sg+0x6b/0x76
__ata_qc_complete+0x7f/0x103
ata_qc_complete+0x9b/0x26a
ata_qc_complete_multiple+0xd0/0xe3
ahci_handle_port_interrupt+0x3ee/0x48a
ahci_handle_port_intr+0x73/0xa9
ahci_single_level_irq_intr+0x40/0x60
__handle_irq_event_percpu+0x7f/0x19a
handle_irq_event_percpu+0x32/0x72
handle_irq_event+0x38/0x56
handle_edge_irq+0x102/0x121
handle_irq+0x147/0x15c
do_IRQ+0x66/0xf2
common_interrupt+0xf/0xf
RIP: 0010:__do_softirq+0x8c/0x2df
The same for usb devices that use ehci-pci:
BUG: spinlock bad magic on CPU#0, swapper/0/1
lock: 0xffff88844f402008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #4
Call Trace:
<IRQ>
dump_stack+0x61/0x7e
spin_bug+0x9d/0xa3
do_raw_spin_lock+0x22/0x8e
_raw_spin_lock_irqsave+0x32/0x3a
queue_iova+0x77/0x145
intel_unmap+0x107/0x113
intel_unmap_page+0xe/0x10
usb_hcd_unmap_urb_setup_for_dma+0x53/0x9d
usb_hcd_unmap_urb_for_dma+0x17/0x100
unmap_urb_for_dma+0x22/0x24
__usb_hcd_giveback_urb+0x51/0xc3
usb_giveback_urb_bh+0x97/0xde
tasklet_action_common.isra.4+0x5f/0xa1
tasklet_action+0x2d/0x30
__do_softirq+0x138/0x2df
irq_exit+0x7d/0x8b
smp_apic_timer_interrupt+0x10f/0x151
apic_timer_interrupt+0xf/0x20
</IRQ>
RIP: 0010:_raw_spin_unlock_irqrestore+0x17/0x39
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: <stable@vger.kernel.org> # 4.14+
Fixes: 13cf017446 ("iommu/vt-d: Make use of iova deferred flushing")
Signed-off-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 59 temple place suite 330 boston ma 02111
1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 33 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000435.254582722@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a 32 bit allocation request is too big to possibly succeed, it
early exits with a failure and then should never update max32_alloc_
size. This patch fixes current code, now the size is only updated if
the slow path failed while walking the tree. Without the fix the
allocation may enter the slow path again even if there was a failure
before of a request with the same or a smaller size.
Cc: <stable@vger.kernel.org> # 4.20+
Fixes: bee60e94a1 ("iommu/iova: Optimise attempts to allocate iova from 32bit address range")
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Robert Richter <rrichter@marvell.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
