Pull dma-mapping updates from Marek Szyprowski:
- More DMA mapping API refactoring to physical addresses as the primary
interface instead of page+offset parameters.
This time dma_map_ops callbacks are converted to physical addresses,
what in turn results also in some simplification of architecture
specific code (Leon Romanovsky and Jason Gunthorpe)
- Clarify that dma_map_benchmark is not a kernel self-test, but
standalone tool (Qinxin Xia)
* tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
dma-mapping: remove unused map_page callback
xen: swiotlb: Convert mapping routine to rely on physical address
x86: Use physical address for DMA mapping
sparc: Use physical address DMA mapping
powerpc: Convert to physical address DMA mapping
parisc: Convert DMA map_page to map_phys interface
MIPS/jazzdma: Provide physical address directly
alpha: Convert mapping routine to rely on physical address
dma-mapping: remove unused mapping resource callbacks
xen: swiotlb: Switch to physical address mapping callbacks
ARM: dma-mapping: Switch to physical address mapping callbacks
ARM: dma-mapping: Reduce struct page exposure in arch_sync_dma*()
dma-mapping: convert dummy ops to physical address mapping
dma-mapping: prepare dma_map_ops to conversion to physical address
tools/dma: move dma_map_benchmark from selftests to tools/dma
Pull MM updates from Andrew Morton:
"__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
Rework the vmalloc() code to support non-blocking allocations
(GFP_ATOIC, GFP_NOWAIT)
"ksm: fix exec/fork inheritance" (xu xin)
Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
inherited across fork/exec
"mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
Some light maintenance work on the zswap code
"mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
Enhance the /sys/kernel/debug/page_owner debug feature by adding
unique identifiers to differentiate the various stack traces so
that userspace monitoring tools can better match stack traces over
time
"mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
Minor alterations to the page allocator's per-cpu-pages feature
"Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
Address a scalability issue in userfaultfd's UFFDIO_MOVE operation
"kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)
"drivers/base/node: fold node register and unregister functions" (Donet Tom)
Clean up the NUMA node handling code a little
"mm: some optimizations for prot numa" (Kefeng Wang)
Cleanups and small optimizations to the NUMA allocation hinting
code
"mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
Address long lock hold times at boot on large machines. These were
causing (harmless) softlockup warnings
"optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
Remove some now-unnecessary work from page reclaim
"mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
Enhance the DAMOS auto-tuning feature
"mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
configuration
"expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
Enhance the new(ish) file_operations.mmap_prepare() method and port
additional callsites from the old ->mmap() over to ->mmap_prepare()
"Fix stale IOTLB entries for kernel address space" (Lu Baolu)
Fix a bug (and possible security issue on non-x86) in the IOMMU
code. In some situations the IOMMU could be left hanging onto a
stale kernel pagetable entry
"mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
Clean up and optimize the folio splitting code
"mm, swap: misc cleanup and bugfix" (Kairui Song)
Some cleanups and a minor fix in the swap discard code
"mm/damon: misc documentation fixups" (SeongJae Park)
"mm/damon: support pin-point targets removal" (SeongJae Park)
Permit userspace to remove a specific monitoring target in the
middle of the current targets list
"mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
A couple of cleanups related to mm header file inclusion
"mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
improve the selection of swap devices for NUMA machines
"mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
Change the memory block labels from macros to enums so they will
appear in kernel debug info
"ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
Address an inefficiency when KSM unmerges an address range
"mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
Fix leaks and unhandled malloc() failures in DAMON userspace unit
tests
"some cleanups for pageout()" (Baolin Wang)
Clean up a couple of minor things in the page scanner's
writeback-for-eviction code
"mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
Move hugetlb's sysfs/sysctl handling code into a new file
"introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
Make the VMA guard regions available in /proc/pid/smaps and
improves the mergeability of guarded VMAs
"mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
Reduce mmap lock contention for callers performing VMA guard region
operations
"vma_start_write_killable" (Matthew Wilcox)
Start work on permitting applications to be killed when they are
waiting on a read_lock on the VMA lock
"mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
Add additional userspace testing of DAMON's "commit" feature
"mm/damon: misc cleanups" (SeongJae Park)
"make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
VMA is merged with another
"mm: support device-private THP" (Balbir Singh)
Introduce support for Transparent Huge Page (THP) migration in zone
device-private memory
"Optimize folio split in memory failure" (Zi Yan)
"mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
Some more cleanups in the folio splitting code
"mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
Clean up our handling of pagetable leaf entries by introducing the
concept of 'software leaf entries', of type softleaf_t
"reparent the THP split queue" (Muchun Song)
Reparent the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory
resources
"unify PMD scan results and remove redundant cleanup" (Wei Yang)
A little cleanup in the hugepage collapse code
"zram: introduce writeback bio batching" (Sergey Senozhatsky)
Improve zram writeback efficiency by introducing batched bio
writeback support
"memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
Clean up our handling of the interrupt safety of some memcg stats
"make vmalloc gfp flags usage more apparent" (Vishal Moola)
Clean up vmalloc's handling of incoming GFP flags
"mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
Teach soft dirty and userfaultfd write protect tracking to use
RISC-V's Svrsw60t59b extension
"mm: swap: small fixes and comment cleanups" (Youngjun Park)
Fix a small bug and clean up some of the swap code
"initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
Start work on converting the vma struct's flags to a bitmap, so we
stop running out of them, especially on 32-bit
"mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
Address a possible bug in the swap discard code and clean things
up a little
[ This merge also reverts commit ebb9aeb980 ("vfio/nvgrace-gpu:
register device memory for poison handling") because it looks
broken to me, I've asked for clarification - Linus ]
* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
mm: fix vma_start_write_killable() signal handling
mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
mm/swapfile: fix list iteration when next node is removed during discard
fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
mm/kfence: add reboot notifier to disable KFENCE on shutdown
memcg: remove inc/dec_lruvec_kmem_state helpers
selftests/mm/uffd: initialize char variable to Null
mm: fix DEBUG_RODATA_TEST indentation in Kconfig
mm: introduce VMA flags bitmap type
tools/testing/vma: eliminate dependency on vma->__vm_flags
mm: simplify and rename mm flags function for clarity
mm: declare VMA flags by bit
zram: fix a spelling mistake
mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
pagemap: update BUDDY flag documentation
mm: swap: remove scan_swap_map_slots() references from comments
mm: swap: change swap_alloc_slow() to void
mm, swap: remove redundant comment for read_swap_cache_async
mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
...
Pull VFIO updates from Alex Williamson:
- Move libvfio selftest artifacts in preparation of more tightly
coupled integration with KVM selftests (David Matlack)
- Fix comment typo in mtty driver (Chu Guangqing)
- Support for new hardware revision in the hisi_acc vfio-pci variant
driver where the migration registers can now be accessed via the PF.
When enabled for this support, the full BAR can be exposed to the
user (Longfang Liu)
- Fix vfio cdev support for VF token passing, using the correct size
for the kernel structure, thereby actually allowing userspace to
provide a non-zero UUID token. Also set the match token callback for
the hisi_acc, fixing VF token support for this this vfio-pci variant
driver (Raghavendra Rao Ananta)
- Introduce internal callbacks on vfio devices to simplify and
consolidate duplicate code for generating VFIO_DEVICE_GET_REGION_INFO
data, removing various ioctl intercepts with a more structured
solution (Jason Gunthorpe)
- Introduce dma-buf support for vfio-pci devices, allowing MMIO regions
to be exposed through dma-buf objects with lifecycle managed through
move operations. This enables low-level interactions such as a
vfio-pci based SPDK drivers interacting directly with dma-buf capable
RDMA devices to enable peer-to-peer operations. IOMMUFD is also now
able to build upon this support to fill a long standing feature gap
versus the legacy vfio type1 IOMMU backend with an implementation of
P2P support for VM use cases that better manages the lifecycle of the
P2P mapping (Leon Romanovsky, Jason Gunthorpe, Vivek Kasireddy)
- Convert eventfd triggering for error and request signals to use RCU
mechanisms in order to avoid a 3-way lockdep reported deadlock issue
(Alex Williamson)
- Fix a 32-bit overflow introduced via dma-buf support manifesting with
large DMA buffers (Alex Mastro)
- Convert nvgrace-gpu vfio-pci variant driver to insert mappings on
fault rather than at mmap time. This conversion serves both to make
use of huge PFNMAPs but also to both avoid corrected RAS events
during reset by now being subject to vfio-pci-core's use of
unmap_mapping_range(), and to enable a device readiness test after
reset (Ankit Agrawal)
- Refactoring of vfio selftests to support multi-device tests and split
code to provide better separation between IOMMU and device objects.
This work also enables a new test suite addition to measure parallel
device initialization latency (David Matlack)
* tag 'vfio-v6.19-rc1' of https://github.com/awilliam/linux-vfio: (65 commits)
vfio: selftests: Add vfio_pci_device_init_perf_test
vfio: selftests: Eliminate INVALID_IOVA
vfio: selftests: Split libvfio.h into separate header files
vfio: selftests: Move vfio_selftests_*() helpers into libvfio.c
vfio: selftests: Rename vfio_util.h to libvfio.h
vfio: selftests: Stop passing device for IOMMU operations
vfio: selftests: Move IOVA allocator into iova_allocator.c
vfio: selftests: Move IOMMU library code into iommu.c
vfio: selftests: Rename struct vfio_dma_region to dma_region
vfio: selftests: Upgrade driver logging to dev_err()
vfio: selftests: Prefix logs with device BDF where relevant
vfio: selftests: Eliminate overly chatty logging
vfio: selftests: Support multiple devices in the same container/iommufd
vfio: selftests: Introduce struct iommu
vfio: selftests: Rename struct vfio_iommu_mode to iommu_mode
vfio: selftests: Allow passing multiple BDFs on the command line
vfio: selftests: Split run.sh into separate scripts
vfio: selftests: Move run.sh into scripts directory
vfio/nvgrace-gpu: wait for the GPU mem to be ready
vfio/nvgrace-gpu: Inform devmem unmapped after reset
...
Pull drm updates from Dave Airlie:
"There was a rather late merge of a new color pipeline feature, that
some userspace projects are blocked on, and has seen a lot of work in
amdgpu. This should have seen some time in -next. There is additional
support for this for Intel, that if it arrives in the next day or two
I'll pass it on in another pull request and you can decide if you want
to take it.
Highlights:
- Arm Ethos NPU accelerator driver
- new DRM color pipeline support
- amdgpu will now run discrete SI/CIK cards instead of radeon, which
enables vulkan support in userspace
- msm gets gen8 gpu support
- initial Xe3P support in xe
Full detail summary:
New driver:
- Arm Ethos-U65/U85 accel driver
Core:
- support the drm color pipeline in vkms/amdgfx
- add support for drm colorop pipeline
- add COLOR PIPELINE plane property
- add DRM_CLIENT_CAP_PLANE_COLOR_PIPELINE
- throttle dirty worker with vblank
- use drm_for_each_bridge_in_chain_scoped in drm's bridge code
- Ensure drm_client_modeset tests are enabled in UML
- add simulated vblank interrupt - use in drivers
- dumb buffer sizing helper
- move freeing of drm client memory to driver
- crtc sharpness strength property
- stop using system_wq in scheduler/drivers
- support emergency restore in drm-client
Rust:
- make slice::as_flattened usable on all supported rustc
- add FromBytes::from_bytes_prefix() method
- remove redundant device ptr from Rust GEM object
- Change how AlwaysRefCounted is implemented for GEM objects
gpuvm:
- Add deferred vm_bo cleanup to GPUVM (for rust)
atomic:
- cleanup and improve state handling interfaces
buddy:
- optimize block management
dma-buf:
- heaps: Create heap per CMA reserved location
- improve userspace documentation
dp:
- add POST_LT_ADJ_REQ training sequence
- DPCD dSC quirk for synaptics panamera devices
- helpers to query branch DSC max throughput
ttm:
- Rename ttm_bo_put to ttm_bo_fini
- allow page protection flags on risc-v
- rework pipelined eviction fence handling
amdgpu:
- enable amdgpu by default for SI/CI dGPUs
- enable DC by default on SI
- refactor CIK/SI enablement
- add ABM KMS property
- Re-enable DM idle optimizations
- DC Analog encoders support
- Powerplay fixes for fiji/iceland
- Enable DC on bonaire by default
- HMM cleanup
- Add new RAS framework
- DML2.1 updates
- YCbCr420 fixes
- DC FP fixes
- DMUB fixes
- LTTPR fixes
- DTBCLK fixes
- DMU cursor offload handling
- Userq validation improvements
- Unify shutdown callback handling
- Suspend improvements
- Power limit code cleanup
- SR-IOV fixes
- AUX backlight fixes
- DCN 3.5 fixes
- HDMI compliance fixes
- DCN 4.0.1 cursor updates
- DCN interrupt fix
- DC KMS full update improvements
- Add additional HDCP traces
- DCN 3.2 fixes
- DP MST fixes
- Add support for new SR-IOV mailbox interface
- UQ reset support
- HDP flush rework
- VCE1 support
amdkfd:
- HMM cleanups
- Relax checks on save area overallocations
- Fix GPU mappings after prefetch
radeon:
- refactor CIK/SI enablement
xe:
- Initial Xe3P support
- panic support on VRAM for display
- fix stolen size check
- Loosen used tracking restriction
- New SR-IOV debugfs structure and debugfs updates
- Hide the GPU madvise flag behind a VM_BIND flag
- Always expose VRAM provisioning data on discrete GPUs
- Allow VRAM mappings for userptr when used with SVM
- Allow pinning of p2p dma-buf
- Use per-tile debugfs where appropriate
- Add documentation for Execution Queues
- PF improvements
- VF migration recovery redesign work
- User / Kernel VRAM partitioning
- Update Tile-based messages
- Allow configfs to disable specific GT types
- VF provisioning and migration improvements
- use SVM range helpers in PT layer
- Initial CRI support
- access VF registers using dedicated MMIO view
- limit number of jobs per exec queue
- add sriov_admin sysfs tree
- more crescent island specific support
- debugfs residency counter
- SRIOV migration work
- runtime registers for GFX 35
i915:
- add initial Xe3p_LPD display version 35 support
- Enable LNL+ content adaptive sharpness filter
- Use optimized VRR guardband
- Enable Xe3p LT PHY
- enable FBC support for Xe3p_LPD display
- add display 30.02 firmware support
- refactor SKL+ watermark latency setup
- refactor fbdev handling
- call i915/xe runtime PM via function pointers
- refactor i915/xe stolen memory/display interfaces
- use display version instead of gfx version in display code
- extend i915_display_info with Type-C port details
- lots of display cleanups/refactorings
- set O_LARGEFILE in __create_shmem
- skuip guc communication warning on reset
- fix time conversions
- defeature DRRS on LNL+
- refactor intel_frontbuffer split between i915/xe/display
- convert inteL_rom interfaces to struct drm_device
- unify display register polling interfaces
- aovid lock inversion when pinning to GGTT on CHV/BXT+VTD
panel:
- Add KD116N3730A08/A12, chromebook mt8189
- JT101TM023, LQ079L1SX01,
- GLD070WX3-SL01 MIPI DSI
- Samsung LTL106AL0, Samsung LTL106AL01
- Raystar RFF500F-AWH-DNN
- Winstar WF70A8SYJHLNGA
- Wanchanglong w552946aaa
- Samsung SOFEF00
- Lenovo X13s panel
- ilitek-ili9881c - add rpi 5" support
- visionx-rm69299 - add backlight support
- edp - support AUI B116XAN02.0
bridge:
- improve ref counting
- ti-sn65dsi86 - add support for DP mode with HPD
- synopsis: support CEC, init timer with correct freq
- ASL CS5263 DP-to-HDMI bridge support
nova-core:
- introduce bitfield! macro
- introduce safe integer converters
- GSP inits to fully booted state on Ampere
- Use more future-proof register for GPU identification
nova-drm:
- select NOVA_CORE
- 64-bit only
nouveau:
- improve reclocking on tegra 186+
- add large page and compression support
msm:
- GPU:
- Gen8 support: A840 (Kaanapali) and X2-85 (Glymur)
- A612 support
- MDSS:
- Added support for Glymur and QCS8300 platforms
- DPU:
- Enabled Quad-Pipe support, unlocking higher resolutions support
- Added support for Glymur platform
- Documented DPU on QCS8300 platform as supported
- DisplayPort:
- Added support for Glymur platform
- Added support lame remapping inside DP block
- Documented DisplayPort controller on QCS8300 and SM6150/QCS615
as supported
tegra:
- NVJPG driver
panfrost:
- display JM contexts over debugfs
- export JM contexts to userspace
- improve error and job handling
panthor:
- support custom ASN_HASH for mt8196
- support mali-G1 GPU
- flush shmem write before mapping buffers uncached
- make timeout per-queue instead of per-job
mediatek:
- MT8195/88 HDMIv2/DDCv2 support
rockchip:
- dsi: add support for RK3368
amdxdna:
- enhance runtime PM
- last hardware error reading uapi
- support firmware debug output
- add resource and telemetry data uapi
- preemption support
imx:
- add driver for HDMI TX Parallel audio interface
ivpu:
- add support for user-managed preemption buffer
- add userptr support
- update JSM firware API to 3.33.0
- add better alloc/free warnings
- fix page fault in unbind all bos
- rework bind/unbind of imported buffers
- enable MCA ECC signalling
- split fw runtime and global memory buffers
- add fdinfo memory statistics
tidss:
- convert to drm logging
- logging cleanup
ast:
- refactor generation init paths
- add per chip generation detect_tx_chip
- set quirks for each chip model
atmel-hlcdc:
- set LCDC_ATTRE register in plane disable
- set correct values for plane scaler
solomon:
- use drm helper for get_modes and move_valid
sitronix:
- fix output position when clearing screens
qaic:
- support dma-buf exports
- support new firmware's READ_DATA implementation
- sahara AIC200 image table update
- add sysfs support
- add coredump support
- add uevents support
- PM support
sun4i:
- layer refactors to decouple plane from output
- improve DE33 support
vc4:
- switch to generic CEC helpers
komeda:
- use drm_ logging functions
vkms:
- configfs support for display configuration
vgem:
- fix fence timer deadlock
etnaviv:
- add HWDB entry for GC8000 Nano Ultra VIP r6205"
* tag 'drm-next-2025-12-03' of https://gitlab.freedesktop.org/drm/kernel: (1869 commits)
Revert "drm/amd: Skip power ungate during suspend for VPE"
drm/amdgpu: use common defines for HUB faults
drm/amdgpu/gmc12: add amdgpu_vm_handle_fault() handling
drm/amdgpu/gmc11: add amdgpu_vm_handle_fault() handling
drm/amdgpu: use static ids for ACP platform devs
drm/amdgpu/sdma6: Update SDMA 6.0.3 FW version to include UMQ protected-fence fix
drm/amdgpu: Forward VMID reservation errors
drm/amdgpu/gmc8: Delegate VM faults to soft IRQ handler ring
drm/amdgpu/gmc7: Delegate VM faults to soft IRQ handler ring
drm/amdgpu/gmc6: Delegate VM faults to soft IRQ handler ring
drm/amdgpu/gmc6: Cache VM fault info
drm/amdgpu/gmc6: Don't print MC client as it's unknown
drm/amdgpu/cz_ih: Enable soft IRQ handler ring
drm/amdgpu/tonga_ih: Enable soft IRQ handler ring
drm/amdgpu/iceland_ih: Enable soft IRQ handler ring
drm/amdgpu/cik_ih: Enable soft IRQ handler ring
drm/amdgpu/si_ih: Enable soft IRQ handler ring
drm/amd/display: fix typo in display_mode_core_structs.h
drm/amd/display: fix Smart Power OLED not working after S4
drm/amd/display: Move RGB-type check for audio sync to DCE HW sequence
...
Pull dma-mapping fixes from Marek Szyprowski:
"Two last minute fixes for the recently modified DMA API infrastructure:
- proper handling of DMA_ATTR_MMIO in dma_iova_unlink() function (me)
- regression fix for the code refactoring related to P2PDMA (Pranjal
Shrivastava)"
* tag 'dma-mapping-6.18-2025-11-27' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
dma-direct: Fix missing sg_dma_len assignment in P2PDMA bus mappings
iommu/dma: add missing support for DMA_ATTR_MMIO for dma_iova_unlink()
Prior to commit a25e7962db ("PCI/P2PDMA: Refactor the p2pdma mapping
helpers"), P2P segments were mapped using the pci_p2pdma_map_segment()
helper. This helper was responsible for populating sg->dma_address,
marking the bus address, and also setting sg_dma_len(sg).
The refactor[1] removed this helper and moved the mapping logic directly
into the callers. While iommu_dma_map_sg() was correctly updated to set
the length in the new flow, it was missed in dma_direct_map_sg().
Thus, in dma_direct_map_sg(), the PCI_P2PDMA_MAP_BUS_ADDR case sets the
dma_address and marks the segment, but immediately executes 'continue',
which causes the loop to skip the standard assignment logic at the end:
sg_dma_len(sg) = sg->length;
As a result, when CONFIG_NEED_SG_DMA_LENGTH is enabled, the dma_length
field remains uninitialized (zero) for P2P bus address mappings. This
breaks upper-layer drivers (for e.g. RDMA/IB) that rely on sg_dma_len()
to determine the transfer size.
Fix this by explicitly setting the DMA length in the
PCI_P2PDMA_MAP_BUS_ADDR case before continuing to the next scatterlist
entry.
Fixes: a25e7962db ("PCI/P2PDMA: Refactor the p2pdma mapping helpers")
Reported-by: Jacob Moroni <jmoroni@google.com>
Signed-off-by: Pranjal Shrivastava <praan@google.com>
[1]
https://lore.kernel.org/all/ac14a0e94355bf898de65d023ccf8a2ad22a3ece.1746424934.git.leon@kernel.org/
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Shivaji Kant <shivajikant@google.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20251126114112.3694469-1-praan@google.com
Update the pci_p2pdma_bus_addr_map() function to take a direct pointer
to the p2pdma_provider structure instead of the pci_p2pdma_map_state.
This simplifies the API by removing the need for callers to extract
the provider from the state structure.
The change updates all callers across the kernel (block layer, IOMMU,
DMA direct, and HMM) to pass the provider pointer directly, making
the code more explicit and reducing unnecessary indirection. This
also removes the runtime warning check since callers now have direct
control over which provider they use.
Tested-by: Alex Mastro <amastro@fb.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20251120-dmabuf-vfio-v9-2-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
In order to create a CMA dma-buf heap instance for each CMA heap region
in the system, we need to collect all of them during boot.
They are created from two main sources: the reserved-memory regions in
the device tree, and the default CMA region created from the
configuration or command line parameters, if no default region is
provided in the device tree.
Let's collect all the device-tree defined CMA regions flagged as
reusable.
Reviewed-by: T.J. Mercier <tjmercier@google.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://lore.kernel.org/r/20251013-dma-buf-ecc-heap-v8-3-04ce150ea3d9@kernel.org
Commit 370645f41e ("dma-mapping: force bouncing if the kmalloc() size is
not cache-line-aligned") introduced DMA_BOUNCE_UNALIGNED_KMALLOC feature
and permitted architecture specific code configure kmalloc slabs with
sizes smaller than the value of dma_get_cache_alignment().
When that feature is enabled, the physical address of some small
kmalloc()-ed buffers might be not aligned to the CPU cachelines, thus not
really suitable for typical DMA. To properly handle that case a SWIOTLB
buffer bouncing is used, so no CPU cache corruption occurs. When that
happens, there is no point reporting a false-positive DMA-API warning that
the buffer is not properly aligned, as this is not a client driver fault.
[m.szyprowski@samsung.com: replace is_swiotlb_allocated() with is_swiotlb_active(), per Catalin]
Link: https://lkml.kernel.org/r/20251010173009.3916215-1-m.szyprowski@samsung.com
Link: https://lkml.kernel.org/r/20251009141508.2342138-1-m.szyprowski@samsung.com
Fixes: 370645f41e ("dma-mapping: force bouncing if the kmalloc() size is not cache-line-aligned")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Inki Dae <m.szyprowski@samsung.com>
Cc: Robin Murohy <robin.murphy@arm.com>
Cc: "Isaac J. Manjarres" <isaacmanjarres@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull dma-mapping updates from Marek Szyprowski:
- Refactoring of DMA mapping API to physical addresses as the primary
interface instead of page+offset parameters
This gets much closer to Matthew Wilcox's long term wish for
struct-pageless IO to cacheable DRAM and is supporting memdesc
project which seeks to substantially transform how struct page works.
An advantage of this approach is the possibility of introducing
DMA_ATTR_MMIO, which covers existing 'dma_map_resource' flow in the
common paths, what in turn lets to use recently introduced
dma_iova_link() API to map PCI P2P MMIO without creating struct page
Developped by Leon Romanovsky and Jason Gunthorpe
- Minor clean-up by Petr Tesarik and Qianfeng Rong
* tag 'dma-mapping-6.18-2025-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
kmsan: fix missed kmsan_handle_dma() signature conversion
mm/hmm: properly take MMIO path
mm/hmm: migrate to physical address-based DMA mapping API
dma-mapping: export new dma_*map_phys() interface
xen: swiotlb: Open code map_resource callback
dma-mapping: implement DMA_ATTR_MMIO for dma_(un)map_page_attrs()
kmsan: convert kmsan_handle_dma to use physical addresses
dma-mapping: convert dma_direct_*map_page to be phys_addr_t based
iommu/dma: implement DMA_ATTR_MMIO for iommu_dma_(un)map_phys()
iommu/dma: rename iommu_dma_*map_page to iommu_dma_*map_phys
dma-mapping: rename trace_dma_*map_page to trace_dma_*map_phys
dma-debug: refactor to use physical addresses for page mapping
iommu/dma: implement DMA_ATTR_MMIO for dma_iova_link().
dma-mapping: introduce new DMA attribute to indicate MMIO memory
swiotlb: Remove redundant __GFP_NOWARN
dma-direct: clean up the logic in __dma_direct_alloc_pages()
Pull MM updates from Andrew Morton:
- "mm, swap: improve cluster scan strategy" from Kairui Song improves
performance and reduces the failure rate of swap cluster allocation
- "support large align and nid in Rust allocators" from Vitaly Wool
permits Rust allocators to set NUMA node and large alignment when
perforning slub and vmalloc reallocs
- "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
DAMOS_STAT's handling of the DAMON operations sets for virtual
address spaces for ops-level DAMOS filters
- "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
Baghdasaryan reduces mmap_lock contention during reads of
/proc/pid/maps
- "mm/mincore: minor clean up for swap cache checking" from Kairui Song
performs some cleanup in the swap code
- "mm: vm_normal_page*() improvements" from David Hildenbrand provides
code cleanup in the pagemap code
- "add persistent huge zero folio support" from Pankaj Raghav provides
a block layer speedup by optionalls making the
huge_zero_pagepersistent, instead of releasing it when its refcount
falls to zero
- "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
the recently added Kexec Handover feature
- "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
Stoakes turns mm_struct.flags into a bitmap. To end the constant
struggle with space shortage on 32-bit conflicting with 64-bit's
needs
- "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
code
- "selftests/mm: Fix false positives and skip unsupported tests" from
Donet Tom fixes a few things in our selftests code
- "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
from David Hildenbrand "allows individual processes to opt-out of
THP=always into THP=madvise, without affecting other workloads on the
system".
It's a long story - the [1/N] changelog spells out the considerations
- "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
the memdesc project. Please see
https://kernelnewbies.org/MatthewWilcox/Memdescs and
https://blogs.oracle.com/linux/post/introducing-memdesc
- "Tiny optimization for large read operations" from Chi Zhiling
improves the efficiency of the pagecache read path
- "Better split_huge_page_test result check" from Zi Yan improves our
folio splitting selftest code
- "test that rmap behaves as expected" from Wei Yang adds some rmap
selftests
- "remove write_cache_pages()" from Christoph Hellwig removes that
function and converts its two remaining callers
- "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
selftests issues
- "introduce kernel file mapped folios" from Boris Burkov introduces
the concept of "kernel file pages". Using these permits btrfs to
account its metadata pages to the root cgroup, rather than to the
cgroups of random inappropriate tasks
- "mm/pageblock: improve readability of some pageblock handling" from
Wei Yang provides some readability improvements to the page allocator
code
- "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
to understand arm32 highmem
- "tools: testing: Use existing atomic.h for vma/maple tests" from
Brendan Jackman performs some code cleanups and deduplication under
tools/testing/
- "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
a couple of 32-bit issues in tools/testing/radix-tree.c
- "kasan: unify kasan_enabled() and remove arch-specific
implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
initialization code into a common arch-neutral implementation
- "mm: remove zpool" from Johannes Weiner removes zspool - an
indirection layer which now only redirects to a single thing
(zsmalloc)
- "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
couple of cleanups in the fork code
- "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
adjustments at various nth_page() callsites, eventually permitting
the removal of that undesirable helper function
- "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
creates a KASAN read-only mode for ARM, using that architecture's
memory tagging feature. It is felt that a read-only mode KASAN is
suitable for use in production systems rather than debug-only
- "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
some tidying in the hugetlb folio allocation code
- "mm: establish const-correctness for pointer parameters" from Max
Kellermann makes quite a number of the MM API functions more accurate
about the constness of their arguments. This was getting in the way
of subsystems (in this case CEPH) when they attempt to improving
their own const/non-const accuracy
- "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
code sites which were confused over when to use free_pages() vs
__free_pages()
- "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
mapletree code accessible to Rust. Required by nouveau and by its
forthcoming successor: the new Rust Nova driver
- "selftests/mm: split_huge_page_test: split_pte_mapped_thp
improvements" from David Hildenbrand adds a fix and some cleanups to
the thp selftesting code
- "mm, swap: introduce swap table as swap cache (phase I)" from Chris
Li and Kairui Song is the first step along the path to implementing
"swap tables" - a new approach to swap allocation and state tracking
which is expected to yield speed and space improvements. This
patchset itself yields a 5-20% performance benefit in some situations
- "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
layer to clean up the ptdesc code a little
- "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
issues in our 5-level pagetable selftesting code
- "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
addresses a couple of minor issues in relatively new memory
allocation profiling feature
- "Small cleanups" from Matthew Wilcox has a few cleanups in
preparation for more memdesc work
- "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
Quanmin Yan makes some changes to DAMON in furtherance of supporting
arm highmem
- "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
Anjum adds that compiler check to selftests code and fixes the
fallout, by removing dead code
- "Improvements to Victim Process Thawing and OOM Reaper Traversal
Order" from zhongjinji makes a number of improvements in the OOM
killer: mainly thawing a more appropriate group of victim threads so
they can release resources
- "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
is a bunch of small and unrelated fixups for DAMON
- "mm/damon: define and use DAMON initialization check function" from
SeongJae Park implement reliability and maintainability improvements
to a recently-added bug fix
- "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
SeongJae Park provides additional transparency to userspace clients
of the DAMON_STAT information
- "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
some constraints on khubepaged's collapsing of anon VMAs. It also
increases the success rate of MADV_COLLAPSE against an anon vma
- "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
from Lorenzo Stoakes moves us further towards removal of
file_operations.mmap(). This patchset concentrates upon clearing up
the treatment of stacked filesystems
- "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
provides some fixes and improvements to mlock's tracking of large
folios. /proc/meminfo's "Mlocked" field became more accurate
- "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
Donet Tom fixes several user-visible KSM stats inaccuracies across
forks and adds selftest code to verify these counters
- "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
some potential but presently benign issues in KSM's mm_slot handling
* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
mm: swap: check for stable address space before operating on the VMA
mm: convert folio_page() back to a macro
mm/khugepaged: use start_addr/addr for improved readability
hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
alloc_tag: fix boot failure due to NULL pointer dereference
mm: silence data-race in update_hiwater_rss
mm/memory-failure: don't select MEMORY_ISOLATION
mm/khugepaged: remove definition of struct khugepaged_mm_slot
mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
hugetlb: increase number of reserving hugepages via cmdline
selftests/mm: add fork inheritance test for ksm_merging_pages counter
mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
drivers/base/node: fix double free in register_one_node()
mm: remove PMD alignment constraint in execmem_vmalloc()
mm/memory_hotplug: fix typo 'esecially' -> 'especially'
mm/rmap: improve mlock tracking for large folios
mm/filemap: map entire large folio faultaround
mm/fault: try to map the entire file folio in finish_fault()
mm/rmap: mlock large folios in try_to_unmap_one()
mm/rmap: fix a mlock race condition in folio_referenced_one()
...
Introduce new DMA mapping functions dma_map_phys() and dma_unmap_phys()
that operate directly on physical addresses instead of page+offset
parameters. This provides a more efficient interface for drivers that
already have physical addresses available.
The new functions are implemented as the primary mapping layer, with
the existing dma_map_page_attrs()/dma_map_resource() and
dma_unmap_page_attrs()/dma_unmap_resource() functions converted to simple
wrappers around the phys-based implementations.
In case dma_map_page_attrs(), the struct page is converted to physical
address with help of page_to_phys() function and dma_map_resource()
provides physical address as is together with addition of DMA_ATTR_MMIO
attribute.
The old page-based API is preserved in mapping.c to ensure that existing
code won't be affected by changing EXPORT_SYMBOL to EXPORT_SYMBOL_GPL
variant for dma_*map_phys().
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/54cc52af91777906bbe4a386113437ba0bcfba9c.1757423202.git.leonro@nvidia.com
Make dma_map_page_attrs() and dma_map_page_attrs() respect
DMA_ATTR_MMIO.
DMA_ATR_MMIO makes the functions behave the same as
dma_(un)map_resource():
- No swiotlb is possible
- Legacy dma_ops arches use ops->map_resource()
- No kmsan
- No arch_dma_map_phys_direct()
The prior patches have made the internal functions called here
support DMA_ATTR_MMIO.
This is also preparation for turning dma_map_resource() into an inline
calling dma_map_phys(DMA_ATTR_MMIO) to consolidate the flows.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/3660e2c78ea409d6c483a215858fb3af52cd0ed3.1757423202.git.leonro@nvidia.com
Convert the DMA direct mapping functions to accept physical addresses
directly instead of page+offset parameters. The functions were already
operating on physical addresses internally, so this change eliminates
the redundant page-to-physical conversion at the API boundary.
The functions dma_direct_map_page() and dma_direct_unmap_page() are
renamed to dma_direct_map_phys() and dma_direct_unmap_phys() respectively,
with their calling convention changed from (struct page *page,
unsigned long offset) to (phys_addr_t phys).
Architecture-specific functions arch_dma_map_page_direct() and
arch_dma_unmap_page_direct() are similarly renamed to
arch_dma_map_phys_direct() and arch_dma_unmap_phys_direct().
The is_pci_p2pdma_page() checks are replaced with DMA_ATTR_MMIO checks
to allow integration with dma_direct_map_resource and dma_direct_map_phys()
is extended to support MMIO path either.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/bb15a22f76dc2e26683333ff54e789606cfbfcf0.1757423202.git.leonro@nvidia.com
Rename the IOMMU DMA mapping functions to better reflect their actual
calling convention. The functions iommu_dma_map_page() and
iommu_dma_unmap_page() are renamed to iommu_dma_map_phys() and
iommu_dma_unmap_phys() respectively, as they already operate on physical
addresses rather than page structures.
The calling convention changes from accepting (struct page *page,
unsigned long offset) to (phys_addr_t phys), which eliminates the need
for page-to-physical address conversion within the functions. This
renaming prepares for the broader DMA API conversion from page-based
to physical address-based mapping throughout the kernel.
All callers are updated to pass physical addresses directly, including
dma_map_page_attrs(), scatterlist mapping functions, and DMA page
allocation helpers. The change simplifies the code by removing the
page_to_phys() + offset calculation that was previously done inside
the IOMMU functions.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/ed172f95f8f57782beae04f782813366894e98df.1757423202.git.leonro@nvidia.com
Convert the DMA debug infrastructure from page-based to physical address-based
mapping as a preparation to rely on physical address for DMA mapping routines.
The refactoring renames debug_dma_map_page() to debug_dma_map_phys() and
changes its signature to accept a phys_addr_t parameter instead of struct page
and offset. Similarly, debug_dma_unmap_page() becomes debug_dma_unmap_phys().
A new dma_debug_phy type is introduced to distinguish physical address mappings
from other debug entry types. All callers throughout the codebase are updated
to pass physical addresses directly, eliminating the need for page-to-physical
conversion in the debug layer.
This refactoring eliminates the need to convert between page pointers and
physical addresses in the debug layer, making the code more efficient and
consistent with the DMA mapping API's physical address focus.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
[mszyprow: added a fixup]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/56d1a6769b68dfcbf8b26a75a7329aeb8e3c3b6a.1757423202.git.leonro@nvidia.com
Link: https://lore.kernel.org/all/20250910052618.GH341237@unreal/
When CONFIG_DMA_DIRECT_REMAP is enabled, atomic pool pages are
remapped via dma_common_contiguous_remap() using the supplied
pgprot. Currently, the mapping uses
pgprot_dmacoherent(PAGE_KERNEL), which leaves the memory encrypted
on systems with memory encryption enabled (e.g., ARM CCA Realms).
This can cause the DMA layer to fail or crash when accessing the
memory, as the underlying physical pages are not configured as
expected.
Fix this by requesting a decrypted mapping in the vmap() call:
pgprot_decrypted(pgprot_dmacoherent(PAGE_KERNEL))
This ensures that atomic pool memory is consistently mapped
unencrypted.
Cc: stable@vger.kernel.org
Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250811181759.998805-1-sdonthineni@nvidia.com
When porting a cma related usage from x86_64 server to arm64 server,
the "cma=4G@4G" setup failed on arm64. The reason is arm64 and some
other architectures have specific physical address limit for reserved
cma area, like 4GB due to the device's need for 32 bit dma. Actually
lots of platforms of those architectures don't have this device dma
limit, but still have to obey it, and are not able to reserve a huge
cma pool.
This situation could be improved by honoring the user input cma
physical address than the arch limit. As when users specify it, they
already knows what the default is which probably can't suit them.
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250612021417.44929-1-feng.tang@linux.alibaba.com
Pull dma-mapping updates from Marek Szyprowski:
"New two step DMA mapping API, which is is a first step to a long path
to provide alternatives to scatterlist and to remove hacks, abuses and
design mistakes related to scatterlists.
This new approach optimizes some calls to DMA-IOMMU layer and cache
maintenance by batching them, reduces memory usage as it is no need to
store mapped DMA addresses to unmap them, and reduces some function
call overhead. It is a combination effort of many people, lead and
developed by Christoph Hellwig and Leon Romanovsky"
* tag 'dma-mapping-6.16-2025-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
docs: core-api: document the IOVA-based API
dma-mapping: add a dma_need_unmap helper
dma-mapping: Implement link/unlink ranges API
iommu/dma: Factor out a iommu_dma_map_swiotlb helper
dma-mapping: Provide an interface to allow allocate IOVA
iommu: add kernel-doc for iommu_unmap_fast
iommu: generalize the batched sync after map interface
dma-mapping: move the PCI P2PDMA mapping helpers to pci-p2pdma.h
PCI/P2PDMA: Refactor the p2pdma mapping helpers
Add helper that allows a driver to skip calling dma_unmap_*
if the DMA layer can guarantee that they are no-nops.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
To support the upcoming non-scatterlist mapping helpers, we need to go
back to have them called outside of the DMA API. Thus move them out of
dma-map-ops.h, which is only for DMA API implementations to pci-p2pdma.h,
which is for driver use.
Note that the core helper is still not exported as the mapping is
expected to be done only by very highlevel subsystem code at least for
now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
The current scheme with a single helper to determine the P2P status
and map a scatterlist segment force users to always use the map_sg
helper to DMA map, which we're trying to get away from because they
are very cache inefficient.
Refactor the code so that there is a single helper that checks the P2P
state for a page, including the result that it is not a P2P page to
simplify the callers, and a second one to perform the address translation
for a bus mapped P2P transfer that does not depend on the scatterlist
structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
When a reserved memory region described in the device tree is attached
to a device, it is expected that the device's limitations are correctly
included in that description.
However, if the device driver failed to implement DMA address masking
or addressing beyond the default 32 bits (on arm64), then bad things
could happen because the DMA address was truncated, such as playing
back audio with no actual audio coming out, or DMA overwriting random
blocks of kernel memory.
Check against the coherent DMA mask when the memory regions are attached
to the device. Give a warning when the memory region can not be covered
by the mask.
A warning instead of a hard error was chosen, because it is possible
that existing drivers could be working fine even if they forgot to
extend the coherent DMA mask.
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250421083930.374173-1-wenst@chromium.org
When building with W=1, this variable is unused for configs with
CONFIG_CMA_SIZE_SEL_PERCENTAGE=y:
kernel/dma/contiguous.c:67:26: error: 'size_bytes' defined but not used [-Werror=unused-const-variable=]
Change this to a macro to avoid the warning.
Fixes: c64be2bb1c ("drivers: add Contiguous Memory Allocator")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250409151557.3890443-1-arnd@kernel.org
Offset into the page should also be considered while calculating a physical
address for struct dma_debug_entry. page_to_phys() just shifts the value
PAGE_SHIFT bits to the left so offset part is zero-filled.
An example (wrong) debug assertion failure with CONFIG_DMA_API_DEBUG
enabled which is observed during systemd boot process after recent
dma-debug changes:
DMA-API: e1000 0000:00:03.0: cacheline tracking EEXIST, overlapping mappings aren't supported
WARNING: CPU: 4 PID: 941 at kernel/dma/debug.c:596 add_dma_entry
CPU: 4 UID: 0 PID: 941 Comm: ip Not tainted 6.12.0+ #288
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:add_dma_entry kernel/dma/debug.c:596
Call Trace:
<TASK>
debug_dma_map_page kernel/dma/debug.c:1236
dma_map_page_attrs kernel/dma/mapping.c:179
e1000_alloc_rx_buffers drivers/net/ethernet/intel/e1000/e1000_main.c:4616
...
Found by Linux Verification Center (linuxtesting.org).
Fixes: 9d4f645a1f ("dma-debug: store a phys_addr_t in struct dma_debug_entry")
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
[hch: added a little helper to clean up the code]
Signed-off-by: Christoph Hellwig <hch@lst.de>
It can be surprising to the user if DMA functions are only traced on
success. On failure, it can be unclear what the source of the problem
is. Fix this by tracing all functions even when they fail. Cases where
we BUG/WARN are skipped, since those should be sufficiently noisy
already.
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In some cases, we use trace_dma_map to trace dma_alloc* functions. This
generally follows dma_debug. However, this does not record all of the
relevant information for allocations, such as GFP flags. Create new
dma_alloc tracepoints for these functions. Note that while
dma_alloc_noncontiguous may allocate discontiguous pages (from the CPU's
point of view), the device will only see one contiguous mapping.
Therefore, we just need to trace dma_addr and size.
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In preparation for using these tracepoints in a few more places, trace
the DMA direction as well. For coherent allocations this is always
bidirectional.
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
