This introduces support for the remoteproc on Mediatek MT8188, and
enables caches for MT8186 SCP. It adds support for PRU cores found on
the TI K3 AM62x SoCs.
It moves the recovery work after a firmware crash to an unbound
workqueue, to allow recovery to happen in parallel.
A new DMA API is introduced to release dma_mem for a device.
It adds support a panic handler for the Qualcomm modem remoteproc, with
the goal of having caches flushed in memory dumps for post-mortem
debugging and it introduces a mechanism to wait for the modem firmware
on SM8450 to decrypt part of its memory for post-mortem debugging.
Qualcomm sysmon is restricted to only inform remote processors about
peers that are actually running, to avoid a race where Linux tries to
notify a recovering remote processor about its peers new state. A
mechanism for waiting for the sysmon connection to be established is also
introduced, to avoid out-of-sync updates for rapidly restarting remote
processors.
A number of Devicetree binding cleanups and conversions to YAML are
introduced, to facilitate Devicetree validation. Lastly it introduces a
number of smaller fixes and cleanups in the core and a few different
drivers.
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Merge tag 'rproc-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux
Pull remoteproc updates from Bjorn Andersson:
"This introduces support for the remoteproc on Mediatek MT8188, and
enables caches for MT8186 SCP. It adds support for PRU cores found on
the TI K3 AM62x SoCs.
It moves the recovery work after a firmware crash to an unbound
workqueue, to allow recovery to happen in parallel.
A new DMA API is introduced to release dma_mem for a device.
It adds support a panic handler for the Qualcomm modem remoteproc,
with the goal of having caches flushed in memory dumps for post-mortem
debugging and it introduces a mechanism to wait for the modem firmware
on SM8450 to decrypt part of its memory for post-mortem debugging.
Qualcomm sysmon is restricted to only inform remote processors about
peers that are actually running, to avoid a race where Linux tries to
notify a recovering remote processor about its peers new state. A
mechanism for waiting for the sysmon connection to be established is
also introduced, to avoid out-of-sync updates for rapidly restarting
remote processors.
A number of Devicetree binding cleanups and conversions to YAML are
introduced, to facilitate Devicetree validation. Lastly it introduces
a number of smaller fixes and cleanups in the core and a few different
drivers"
* tag 'rproc-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux: (42 commits)
remoteproc: qcom_q6v5_pas: Do not fail if regulators are not found
drivers/remoteproc: fix repeated words in comments
remoteproc: Directly use ida_alloc()/free()
remoteproc: Use unbounded workqueue for recovery work
remoteproc: using pm_runtime_resume_and_get instead of pm_runtime_get_sync
remoteproc: qcom_q6v5_pas: Deal silently with optional px and cx regulators
remoteproc: sysmon: Send sysmon state only for running rprocs
remoteproc: sysmon: Wait for SSCTL service to come up
remoteproc: qcom: q6v5: Set q6 state to offline on receiving wdog irq
remoteproc: qcom: pas: Check if coredump is enabled
remoteproc: qcom: pas: Mark devices as wakeup capable
remoteproc: qcom: pas: Mark va as io memory
remoteproc: qcom: pas: Add decrypt shutdown support for modem
remoteproc: qcom: q6v5-mss: add powerdomains to MSM8996 config
remoteproc: qcom_q6v5: Introduce panic handler for MSS
remoteproc: qcom_q6v5_mss: Update MBA log info
remoteproc: qcom: correct kerneldoc
remoteproc: qcom_q6v5_mss: map/unmap metadata region before/after use
remoteproc: qcom: using pm_runtime_resume_and_get to simplify the code
remoteproc: mediatek: Support MT8188 SCP
...
- 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
...
Debugfs node will be run-timely checked and so local variable
should be not passed to debugfs_create_ulong(). Fix it via
debugfs_create_file() to create io_tlb_used node and calculate
used io tlb number with fops_io_tlb_used attribute.
Fixes: 20347fca71 ("swiotlb: split up the global swiotlb lock")
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
make html doc reports a cryptic warning with the commit named below:
kernel/dma/mapping.c:258: WARNING: Option list ends without a blank
line; unexpected unindent.
Seems the parser is a bit fussy about the tabbing and having a single
space tab causes the warning. To suppress the warning add another
tab to the list and reindent everything.
Fixes: 7c2645a2a3 ("dma-mapping: allow EREMOTEIO return code for P2PDMA transfers")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a flags member to the dma_map_ops structure with one flag to
indicate support for PCI P2PDMA.
Also, add a helper to check if a device supports PCI P2PDMA.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add PCI P2PDMA support for dma_direct_map_sg() so that it can map
PCI P2PDMA pages directly without a hack in the callers. This allows
for heterogeneous SGLs that contain both P2PDMA and regular pages.
A P2PDMA page may have three possible outcomes when being mapped:
1) If the data path between the two devices doesn't go through the
root port, then it should be mapped with a PCI bus address
2) If the data path goes through the host bridge, it should be mapped
normally, as though it were a CPU physical address
3) It is not possible for the two devices to communicate and thus
the mapping operation should fail (and it will return -EREMOTEIO).
SGL segments that contain PCI bus addresses are marked with
sg_dma_mark_pci_p2pdma() and are ignored when unmapped.
P2PDMA mappings are also failed if swiotlb needs to be used on the
mapping.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add EREMOTEIO error return to dma_map_sgtable() which will be used
by .map_sg() implementations that detect P2PDMA pages that the
underlying DMA device cannot access.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
- Fix the used field of struct io_tlb_area wasn't initialized
- Set area number to be 0 if input area number parameter is 0
- Use array_size() to calculate io_tlb_area array size
- Make parameters of swiotlb_do_find_slots() more reasonable
Fixes: 26ffb91fa5e0 ("swiotlb: split up the global swiotlb lock")
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Streaming DMA mapping involving an IOMMU may be much slower for larger
total mapping size. This is because every IOMMU DMA mapping requires an
IOVA to be allocated and freed. IOVA sizes above a certain limit are not
cached, which can have a big impact on DMA mapping performance.
Provide an API for device drivers to know this "optimal" limit, such that
they may try to produce mapping which don't exceed it.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Free slots tracking assumes that slots in a segment can be allocated to
fulfill a request. This implies that slots in a segment should belong to
the same area. Although the possibility of a violation is low, it is better
to explicitly enforce segments won't span multiple areas by adjusting the
number of slabs when configuring areas.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
default_nslabs are rounded up in two cases with exactly same comments.
Add a simple wrapper to reduce duplicate code/comments. It is preparatory
to adding more logics into the round-up.
No functional change intended.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Commit 20347fca71 ("swiotlb: split up the global swiotlb lock") splits
io_tlb_mem into multiple areas. Each area has its own lock and index. The
global ones are not used so remove them.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Don't dereference "mem" after it has been freed. Flip the
two kfree()s around to address this bug.
Fixes: 26ffb91fa5e0 ("swiotlb: split up the global swiotlb lock")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Traditionally swiotlb was not performance critical because it was only
used for slow devices. But in some setups, like TDX/SEV confidential
guests, all IO has to go through swiotlb. Currently swiotlb only has a
single lock. Under high IO load with multiple CPUs this can lead to
significat lock contention on the swiotlb lock.
This patch splits the swiotlb bounce buffer pool into individual areas
which have their own lock. Each CPU tries to allocate in its own area
first. Only if that fails does it search other areas. On freeing the
allocation is freed into the area where the memory was originally
allocated from.
Area number can be set via swiotlb kernel parameter and is default
to be possible cpu number. If possible cpu number is not power of
2, area number will be round up to the next power of 2.
This idea from Andi Kleen patch(https://github.com/intel/tdx/commit/
4529b5784c141782c72ec9bd9a92df2b68cb7d45).
Based-on-idea-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In the failure case of trying to use a buffer which we'd previously
failed to allocate, the "!mem" condition is no longer sufficient since
io_tlb_default_mem became static and assigned by default. Update the
condition to work as intended per the rest of that conversion.
Fixes: 463e862ac6 ("swiotlb: Convert io_default_tlb_mem to static allocation")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add dma_release_coherent_memory to DMA API to allow dma
user call it to release dev->dma_mem when the device is
removed.
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220422062436.14384-2-mark-pk.tsai@mediatek.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
The third parameter of dma_set_encrypted() is a size in bytes rather than
the number of pages.
Fixes: 4d0564785b ("dma-direct: factor out dma_set_{de,en}crypted helpers")
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Panic on purpose if nslabs is too small, in order to sync with the remap
retry logic.
In addition, print the number of bytes for tlb alloc failure.
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Both swiotlb_init_remap() and swiotlb_init() have return type void.
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The swiotlb_init refactor messed up assigning ->force_bounce by doing
it in different places based on what caused the setting of the flag.
Fix this by passing the SWIOTLB_* flags to swiotlb_init_io_tlb_mem
and just setting it there.
Fixes: c6af2aa9ff ("swiotlb: make the swiotlb_init interface more useful")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Limit the error msg to avoid flooding the console. If you have a lot of
threads hitting this at once, they could have already gotten passed the
dma_debug_disabled() check before they get to the point of allocation
failure, resulting in quite a lot of this error message spamming the
log. Use pr_err_once() to limit that.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The original x86 sev_alloc() only called set_memory_decrypted() on
memory returned by alloc_pages_node(), so the page order calculation
fell out of that logic. However, the common dma-direct code has several
potential allocators, not all of which are guaranteed to round up the
underlying allocation to a power-of-two size, so carrying over that
calculation for the encryption/decryption size was a mistake. Fix it by
rounding to a *number* of pages, rather than an order.
Until recently there was an even worse interaction with DMA_DIRECT_REMAP
where we could have ended up decrypting part of the next adjacent
vmalloc area, only averted by no architecture actually supporting both
configs at once. Don't ask how I found that one out...
Fixes: c10f07aa27 ("dma/direct: Handle force decryption for DMA coherent buffers in common code")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Rientjes <rientjes@google.com>
swiotlb_find_slots() skips slots according to io tlb aligned mask
calculated from min aligned mask and original physical address
offset. This affects max mapping size. The mapping size can't
achieve the IO_TLB_SEGSIZE * IO_TLB_SIZE when original offset is
non-zero. This will cause system boot up failure in Hyper-V
Isolation VM where swiotlb force is enabled. Scsi layer use return
value of dma_max_mapping_size() to set max segment size and it
finally calls swiotlb_max_mapping_size(). Hyper-V storage driver
sets min align mask to 4k - 1. Scsi layer may pass 256k length of
request buffer with 0~4k offset and Hyper-V storage driver can't
get swiotlb bounce buffer via DMA API. Swiotlb_find_slots() can't
find 256k length bounce buffer with offset. Make swiotlb_max_mapping
_size() take min align mask into account.
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
nslabs can shrink when allocations or the remap don't succeed, so make
sure to use it for all sizing. For that remove the bytes value that
can get stale and replace it with local calculations and a boolean to
indicate if the originally requested size could not be allocated.
Fixes: 6424e31b1c ("swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
default_nslabs should only be used to initialize nslabs, after that we
need to use the local variable that can shrink when allocations or the
remap don't succeed.
Fixes: 6424e31b1c ("swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
For historical reasons the switlb code paniced when the metadata could
not be allocated, but just printed a warning when the actual main
swiotlb buffer could not be allocated. Restore this somewhat unexpected
behavior as changing it caused a boot failure on the Microchip RISC-V
PolarFire SoC Icicle kit.
Fixes: 6424e31b1c ("swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl")
Reported-by: Conor Dooley <Conor.Dooley@microchip.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <Conor.Dooley@microchip.com>
We observed the error "cacheline tracking ENOMEM, dma-debug disabled"
during a light system load (copying some files). The reason for this error
is that the dma_active_cacheline radix tree uses GFP_NOWAIT allocation -
so it can't access the emergency memory reserves and it fails as soon as
anybody reaches the watermark.
This patch changes GFP_NOWAIT to GFP_ATOMIC, so that it can access the
emergency memory reserves.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
When dma_direct_alloc_pages encounters a highmem page it just gives up
currently. But what we really should do is to try memory using the
page allocator instead - without this platforms with a global highmem
CMA pool will fail all dma_alloc_pages allocations.
Fixes: efa70f2fdc ("dma-mapping: add a new dma_alloc_pages API")
Reported-by: Mark O'Neill <mao@tumblingdice.co.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
No users left.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
To shared more code between swiotlb and xen-swiotlb, offer a
swiotlb_init_remap interface and add a remap callback to
swiotlb_init_late that will allow Xen to remap the buffer without
duplicating much of the logic.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Let the caller chose a zone to allocate from. This will be used
later on by the xen-swiotlb initialization on arm.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Power SVM wants to allocate a swiotlb buffer that is not restricted to
low memory for the trusted hypervisor scheme. Consolidate the support
for this into the swiotlb_init interface by adding a new flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pass a boolean flag to indicate if swiotlb needs to be enabled based on
the addressing needs, and replace the verbose argument with a set of
flags, including one to force enable bounce buffering.
Note that this patch removes the possibility to force xen-swiotlb use
with the swiotlb=force parameter on the command line on x86 (arm and
arm64 never supported that), but this interface will be restored shortly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
swiotlb_late_init_with_default_size is an overly verbose name that
doesn't even catch what the function is doing, given that the size is
not just a default but the actual requested size.
Rename it to swiotlb_init_late.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Remove the bogus Xen override that was usually larger than the actual
size and just calculate the value on demand. Note that
swiotlb_max_segment still doesn't make sense as an interface and should
eventually be removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
If force bouncing is enabled we can't release the buffers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Use the more specific is_swiotlb_active check instead of checking the
global swiotlb_force variable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
When we looked into FIO performance with swiotlb enabled in VM, we found
swiotlb_bounce() is always called one more time than expected for each DMA
read request.
It turns out that the bounce buffer is copied to original DMA buffer twice
after the completion of a DMA request (one is done by in
dma_direct_sync_single_for_cpu(), the other by swiotlb_tbl_unmap_single()).
But the content in bounce buffer actually doesn't change between the two
rounds of copy. So, one round of copy is redundant.
Pass DMA_ATTR_SKIP_CPU_SYNC flag to swiotlb_tbl_unmap_single() to
skip the memory copy in it.
This fix increases FIO 64KB sequential read throughput in a guest with
swiotlb=force by 5.6%.
Fixes: 55897af630 ("dma-direct: merge swiotlb_dma_ops into the dma_direct code")
Reported-by: Wang Zhaoyang1 <zhaoyang1.wang@intel.com>
Reported-by: Gao Liang <liang.gao@intel.com>
Signed-off-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
pgprot_decrypted is used by AMD SME systems to allow access to memory
that was set to not encrypted using set_memory_decrypted. That only
happens for dma-direct memory as the IOMMU solves the addressing
challenges for the encryption bit using its own remapping.
Move the pgprot_decrypted call out of dma_pgprot which is also used
by the IOMMU mappings and into dma-direct so that it is only used with
memory that was set decrypted.
Fixes: f5ff79fddf ("dma-mapping: remove CONFIG_DMA_REMAP")
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
- do not zero buffer in set_memory_decrypted (Kirill A. Shutemov)
- fix return value of dma-debug __setup handlers (Randy Dunlap)
- swiotlb cleanups (Robin Murphy)
- remove most remaining users of the pci-dma-compat.h API
(Christophe JAILLET)
- share the ABI header for the DMA map_benchmark with userspace
(Tian Tao)
- update the maintainer for DMA MAPPING BENCHMARK (Xiang Chen)
- remove CONFIG_DMA_REMAP (me)
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Merge tag 'dma-mapping-5.18' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- do not zero buffer in set_memory_decrypted (Kirill A. Shutemov)
- fix return value of dma-debug __setup handlers (Randy Dunlap)
- swiotlb cleanups (Robin Murphy)
- remove most remaining users of the pci-dma-compat.h API
(Christophe JAILLET)
- share the ABI header for the DMA map_benchmark with userspace
(Tian Tao)
- update the maintainer for DMA MAPPING BENCHMARK (Xiang Chen)
- remove CONFIG_DMA_REMAP (me)
* tag 'dma-mapping-5.18' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: benchmark: extract a common header file for map_benchmark definition
dma-debug: fix return value of __setup handlers
dma-mapping: remove CONFIG_DMA_REMAP
media: v4l2-pci-skeleton: Remove usage of the deprecated "pci-dma-compat.h" API
rapidio/tsi721: Remove usage of the deprecated "pci-dma-compat.h" API
sparc: Remove usage of the deprecated "pci-dma-compat.h" API
agp/intel: Remove usage of the deprecated "pci-dma-compat.h" API
alpha: Remove usage of the deprecated "pci-dma-compat.h" API
MAINTAINERS: update maintainer list of DMA MAPPING BENCHMARK
swiotlb: simplify array allocation
swiotlb: tidy up includes
swiotlb: simplify debugfs setup
swiotlb: do not zero buffer in set_memory_decrypted()
Halil Pasic points out [1] that the full revert of that commit (revert
in bddac7c1e0), and that a partial revert that only reverts the
problematic case, but still keeps some of the cleanups is probably
better. 
And that partial revert [2] had already been verified by Oleksandr
Natalenko to also fix the issue, I had just missed that in the long
discussion.
So let's reinstate the cleanups from commit aa6f8dcbab ("swiotlb:
rework "fix info leak with DMA_FROM_DEVICE""), and effectively only
revert the part that caused problems.
Link: https://lore.kernel.org/all/20220328013731.017ae3e3.pasic@linux.ibm.com/ [1]
Link: https://lore.kernel.org/all/20220324055732.GB12078@lst.de/ [2]
Link: https://lore.kernel.org/all/4386660.LvFx2qVVIh@natalenko.name/ [3]
Suggested-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: Christoph Hellwig" <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit aa6f8dcbab.
It turns out this breaks at least the ath9k wireless driver, and
possibly others.
What the ath9k driver does on packet receive is to set up the DMA
transfer with:
int ath_rx_init(..)
..
bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
common->rx_bufsize,
DMA_FROM_DEVICE);
and then the receive logic (through ath_rx_tasklet()) will fetch
incoming packets
static bool ath_edma_get_buffers(..)
..
dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
common->rx_bufsize, DMA_FROM_DEVICE);
ret = ath9k_hw_process_rxdesc_edma(ah, rs, skb->data);
if (ret == -EINPROGRESS) {
/*let device gain the buffer again*/
dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
common->rx_bufsize, DMA_FROM_DEVICE);
return false;
}
and it's worth noting how that first DMA sync:
dma_sync_single_for_cpu(..DMA_FROM_DEVICE);
is there to make sure the CPU can read the DMA buffer (possibly by
copying it from the bounce buffer area, or by doing some cache flush).
The iommu correctly turns that into a "copy from bounce bufer" so that
the driver can look at the state of the packets.
In the meantime, the device may continue to write to the DMA buffer, but
we at least have a snapshot of the state due to that first DMA sync.
But that _second_ DMA sync:
dma_sync_single_for_device(..DMA_FROM_DEVICE);
is telling the DMA mapping that the CPU wasn't interested in the area
because the packet wasn't there. In the case of a DMA bounce buffer,
that is a no-op.
Note how it's not a sync for the CPU (the "for_device()" part), and it's
not a sync for data written by the CPU (the "DMA_FROM_DEVICE" part).
Or rather, it _should_ be a no-op. That's what commit aa6f8dcbab
broke: it made the code bounce the buffer unconditionally, and changed
the DMA_FROM_DEVICE to just unconditionally and illogically be
DMA_TO_DEVICE.
[ Side note: purely within the confines of the swiotlb driver it wasn't
entirely illogical: The reason it did that odd DMA_FROM_DEVICE ->
DMA_TO_DEVICE conversion thing is because inside the swiotlb driver,
it uses just a swiotlb_bounce() helper that doesn't care about the
whole distinction of who the sync is for - only which direction to
bounce.
So it took the "sync for device" to mean that the CPU must have been
the one writing, and thought it meant DMA_TO_DEVICE. ]
Also note how the commentary in that commit was wrong, probably due to
that whole confusion, claiming that the commit makes the swiotlb code
"bounce unconditionally (that is, also
when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale
data from the swiotlb buffer"
which is nonsensical for two reasons:
- that "also when dir == DMA_TO_DEVICE" is nonsensical, as that was
exactly when it always did - and should do - the bounce.
- since this is a sync for the device (not for the CPU), we're clearly
fundamentally not coping back stale data from the bounce buffers at
all, because we'd be copying *to* the bounce buffers.
So that commit was just very confused. It confused the direction of the
synchronization (to the device, not the cpu) with the direction of the
DMA (from the device).
Reported-and-bisected-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Olha Cherevyk <olha.cherevyk@gmail.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Toke Høiland-Jørgensen <toke@toke.dk>
Cc: Maxime Bizon <mbizon@freebox.fr>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SoC specific code is generally used for older platforms that don't (yet)
use device tree to do the same things.
- Support is added for i.MXRT10xx, a Cortex-M7 based microcontroller
from NXP. At the moment this is still incomplete as other portions
are merged through different trees.
- Long abandoned support for running NOMMU ARMv4 or ARMv5 platforms
gets removed, now the Arm NOMMU platforms are limited to the
Cortex-M family of microcontrollers
- Two old PXA boards get removed, along with corresponding driver
bits.
- Continued cleanup of the Intel IXP4xx platforms, removing some
remnants of the old board files.
- Minor Cleanups and fixes for Orion, PXA, MMP, Mstar, Samsung
- CPU idle support for AT91
- A system controller driver for Polarfire
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Merge tag 'arm-soc-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC updates from Arnd Bergmann:
"SoC specific code is generally used for older platforms that don't
(yet) use device tree to do the same things.
- Support is added for i.MXRT10xx, a Cortex-M7 based microcontroller
from NXP. At the moment this is still incomplete as other portions
are merged through different trees.
- Long abandoned support for running NOMMU ARMv4 or ARMv5 platforms
gets removed, now the Arm NOMMU platforms are limited to the
Cortex-M family of microcontrollers
- Two old PXA boards get removed, along with corresponding driver
bits.
- Continued cleanup of the Intel IXP4xx platforms, removing some
remnants of the old board files.
- Minor Cleanups and fixes for Orion, PXA, MMP, Mstar, Samsung
- CPU idle support for AT91
- A system controller driver for Polarfire"
* tag 'arm-soc-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (29 commits)
ARM: remove support for NOMMU ARMv4/v5
ARM: PXA: fix up decompressor code
soc: microchip: make mpfs_sys_controller_put static
ARM: pxa: remove Intel Imote2 and Stargate 2 boards
ARM: mmp: Fix failure to remove sram device
ARM: mstar: Select ARM_ERRATA_814220
soc: add microchip polarfire soc system controller
ARM: at91: Kconfig: select PM_OPP
ARM: at91: PM: add cpu idle support for sama7g5
ARM: at91: ddr: fix typo to align with datasheet naming
ARM: at91: ddr: align macro definitions
ARM: at91: ddr: remove CONFIG_SOC_SAMA7 dependency
ARM: ixp4xx: Convert to SPARSE_IRQ and P2V
ARM: ixp4xx: Drop all common code
ARM: ixp4xx: Drop custom DMA coherency and bouncing
ARM: ixp4xx: Remove feature bit accessors
net: ixp4xx_hss: Check features using syscon
net: ixp4xx_eth: Drop platform data support
soc: ixp4xx-npe: Access syscon regs using regmap
soc: ixp4xx: Add features from regmap helper
...
Patch series "mm: enforce pageblock_order < MAX_ORDER".
Having pageblock_order >= MAX_ORDER seems to be able to happen in corner
cases and some parts of the kernel are not prepared for it.
For example, Aneesh has shown [1] that such kernels can be compiled on
ppc64 with 64k base pages by setting FORCE_MAX_ZONEORDER=8, which will
run into a WARN_ON_ONCE(order >= MAX_ORDER) in comapction code right
during boot.
We can get pageblock_order >= MAX_ORDER when the default hugetlb size is
bigger than the maximum allocation granularity of the buddy, in which
case we are no longer talking about huge pages but instead gigantic
pages.
Having pageblock_order >= MAX_ORDER can only make alloc_contig_range()
of such gigantic pages more likely to succeed.
Reliable use of gigantic pages either requires boot time allcoation or
CMA, no need to overcomplicate some places in the kernel to optimize for
corner cases that are broken in other areas of the kernel.
This patch (of 2):
Let's enforce pageblock_order < MAX_ORDER and simplify.
Especially patch #1 can be regarded a cleanup before:
[PATCH v5 0/6] Use pageblock_order for cma and alloc_contig_range
alignment. [2]
[1] https://lkml.kernel.org/r/87r189a2ks.fsf@linux.ibm.com
[2] https://lkml.kernel.org/r/20220211164135.1803616-1-zi.yan@sent.com
Link: https://lkml.kernel.org/r/20220214174132.219303-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: John Garry via iommu <iommu@lists.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/dma/map_benchmark.c and selftests/dma/dma_map_benchmark.c
have duplicate map_benchmark definitions, which tends to lead to
inconsistent changes to map_benchmark on both sides, extract a
common header file to avoid this problem.
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Unfortunately, we ended up merging an old version of the patch "fix info
leak with DMA_FROM_DEVICE" instead of merging the latest one. Christoph
(the swiotlb maintainer), he asked me to create an incremental fix
(after I have pointed this out the mix up, and asked him for guidance).
So here we go.
The main differences between what we got and what was agreed are:
* swiotlb_sync_single_for_device is also required to do an extra bounce
* We decided not to introduce DMA_ATTR_OVERWRITE until we have exploiters
* The implantation of DMA_ATTR_OVERWRITE is flawed: DMA_ATTR_OVERWRITE
must take precedence over DMA_ATTR_SKIP_CPU_SYNC
Thus this patch removes DMA_ATTR_OVERWRITE, and makes
swiotlb_sync_single_for_device() bounce unconditionally (that is, also
when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale
data from the swiotlb buffer.
Let me note, that if the size used with dma_sync_* API is less than the
size used with dma_[un]map_*, under certain circumstances we may still
end up with swiotlb not being transparent. In that sense, this is no
perfect fix either.
To get this bullet proof, we would have to bounce the entire
mapping/bounce buffer. For that we would have to figure out the starting
address, and the size of the mapping in
swiotlb_sync_single_for_device(). While this does seem possible, there
seems to be no firm consensus on how things are supposed to work.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Fixes: ddbd89deb7 ("swiotlb: fix info leak with DMA_FROM_DEVICE")
Cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When valid kernel command line parameters
dma_debug=off dma_debug_entries=100
are used, they are reported as Unknown parameters and added to init's
environment strings, polluting it.
Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc5
dma_debug=off dma_debug_entries=100", will be passed to user space.
and
Run /sbin/init as init process
with arguments:
/sbin/init
with environment:
HOME=/
TERM=linux
BOOT_IMAGE=/boot/bzImage-517rc5
dma_debug=off
dma_debug_entries=100
Return 1 from these __setup handlers to indicate that the command line
option has been handled.
Fixes: 59d3daafa1 ("dma-debug: add kernel command line parameters")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: iommu@lists.linux-foundation.org
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
CONFIG_DMA_REMAP is used to build a few helpers around the core
vmalloc code, and to use them in case there is a highmem page in
dma-direct, and to make dma coherent allocations be able to use
non-contiguous pages allocations for DMA allocations in the dma-iommu
layer.
Right now it needs to be explicitly selected by architectures, and
is only done so by architectures that require remapping to deal
with devices that are not DMA coherent. Make it unconditional for
builds with CONFIG_MMU as it is very little extra code, but makes
it much more likely that large DMA allocations succeed on x86.
This fixes hot plugging a NVMe thunderbolt SSD for me, which tries
to allocate a 1MB buffer that is otherwise hard to obtain due to
memory fragmentation on a heavily used laptop.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
The problem I'm addressing was discovered by the LTP test covering
cve-2018-1000204.
A short description of what happens follows:
1) The test case issues a command code 00 (TEST UNIT READY) via the SG_IO
interface with: dxfer_len == 524288, dxdfer_dir == SG_DXFER_FROM_DEV
and a corresponding dxferp. The peculiar thing about this is that TUR
is not reading from the device.
2) In sg_start_req() the invocation of blk_rq_map_user() effectively
bounces the user-space buffer. As if the device was to transfer into
it. Since commit a45b599ad8 ("scsi: sg: allocate with __GFP_ZERO in
sg_build_indirect()") we make sure this first bounce buffer is
allocated with GFP_ZERO.
3) For the rest of the story we keep ignoring that we have a TUR, so the
device won't touch the buffer we prepare as if the we had a
DMA_FROM_DEVICE type of situation. My setup uses a virtio-scsi device
and the buffer allocated by SG is mapped by the function
virtqueue_add_split() which uses DMA_FROM_DEVICE for the "in" sgs (here
scatter-gather and not scsi generics). This mapping involves bouncing
via the swiotlb (we need swiotlb to do virtio in protected guest like
s390 Secure Execution, or AMD SEV).
4) When the SCSI TUR is done, we first copy back the content of the second
(that is swiotlb) bounce buffer (which most likely contains some
previous IO data), to the first bounce buffer, which contains all
zeros. Then we copy back the content of the first bounce buffer to
the user-space buffer.
5) The test case detects that the buffer, which it zero-initialized,
ain't all zeros and fails.
One can argue that this is an swiotlb problem, because without swiotlb
we leak all zeros, and the swiotlb should be transparent in a sense that
it does not affect the outcome (if all other participants are well
behaved).
Copying the content of the original buffer into the swiotlb buffer is
the only way I can think of to make swiotlb transparent in such
scenarios. So let's do just that if in doubt, but allow the driver
to tell us that the whole mapped buffer is going to be overwritten,
in which case we can preserve the old behavior and avoid the performance
impact of the extra bounce.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Linus Torvalds