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2026-08-24Merge tags 'dma-mapping-7.3-2026-08-24' and 'dma-mapping-7.3-2026-08-24-2' ↵Linus Torvalds1-79/+250
of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux Pull dma-mapping updates from Marek Szyprowski: - swiotlb: - new configuration option for the default pool size (Jagadeesh Pagadala) - reduce overhead for high watermark tracking (chenhuguanshen) - minor code cleanups and improvements (Vova Sharaienko, Honglei Huang and Marek Szyprowski) - add proper tracking of the shared DMA state through direct, pool and swiotlb paths (Aneesh Kumar K.V) This is important for confidential-computing * tag 'dma-mapping-7.3-2026-08-24' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma/swiotlb: decouple high watermark tracking from CONFIG_DEBUG_FS MAINTAINERS: update tree for DMA MAPPING HELPERS dma/swiotlb: introduce Kconfig option for compile-time default pool size dma-direct: Improve readability of the dma_direct_map_sg() for P2PDMA case iommu/dma: simplify dma_iova_destroy() and drop the free_iova helper dma-coherent: use KiB in DMA allocation logs dma-coherent: fix spacing coding style issue * tag 'dma-mapping-7.3-2026-08-24-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: (23 commits) swiotlb: remove unused SWIOTLB_FORCE flag dma: swiotlb: handle set_memory_decrypted() failures dma: swiotlb: free dynamic pools from process context dma-direct: rename ret to cpu_addr in alloc helpers dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED dma-direct: set decrypted flag for remapped DMA allocations dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED dma-direct: Move dma_direct_map_phys() to dma/direct.c dma-direct: pass attrs to dma_capable() for DMA_ATTR_CC_SHARED checks dma-mapping: make dma_pgprot() honor __DMA_ATTR_ALLOC_CC_SHARED dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED dma: swiotlb: pass mapping attributes by reference dma-pool: track decrypted atomic pools and select them via attrs dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free paths dma-mapping: Add internal shared allocation attribute coco: arm64: s390: powerpc: Mark secure guests with CC_ATTR_GUEST_MEM_ENCRYPT dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pages s390: Expose protected virtualization through cc_platform_has() swiotlb: Preserve allocation virtual address for dynamic pools dma: free atomic pool pages by physical address ...
2026-08-04mm: prefer vma_[start,end]_pgoff() to vma->vm_pgoff in kernel/Lorenzo Stoakes1-2/+4
Be consistent in using vma_start_pgoff() and vma_end_pgoff(), which clearly indicates which part of the VMA the page offset refers to and aids greppability. This is part of a broader series laying the ground to provide a virtual page offset for MAP_PRIVATE-file backed anon folios. No functional change intended. Link: https://lore.kernel.org/20260710-b4-pre-scalable-cow-v2-19-2a5aa403d977@kernel.org Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> # for kernel/dma Reviewed-by: Gregory Price <gourry@gourry.net> Acked-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Ackerley Tng <ackerleytng@google.com> Cc: David Hildenbrand (Arm) <david@kernel.org> Cc: Kai Huang <kai.huang@intel.com> Cc: SJ Park <sj@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Liam R. Howlett (Oracle) <liam@infradead.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-31dma-direct: rename ret to cpu_addr in alloc helpersAneesh Kumar K.V (Arm)1-20/+20
ret in dma_direct_alloc() and dma_direct_alloc_pages() holds the returned CPU mapping, not a generic return value. Rename it to cpu_addr and update the remaining uses to match. This makes the allocation paths easier to follow and keeps the local naming consistent with what the variable actually represents. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-21-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHAREDAneesh Kumar K.V (Arm)1-17/+26
Make the dma-direct helpers derive the DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED instead of implicitly relying on force_dma_unencrypted() inside phys_to_dma_direct() Pass an explicit unencrypted/decrypted state into phys_to_dma_direct(), make the alloc paths return DMA addresses that match the requested buffer encryption state. Also only call dma_set_decrypted() when __DMA_ATTR_ALLOC_CC_SHARED is actually set. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-20-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: set decrypted flag for remapped DMA allocationsAneesh Kumar K.V (Arm)1-12/+44
Devices that are DMA non-coherent and require a remap were skipping dma_set_decrypted(), leaving DMA buffers encrypted even when the device requires unencrypted access. Move the call after the if (remap) branch so that both the direct and remapped allocation paths correctly mark the allocation as decrypted (or fail cleanly) before use. Fix dma_direct_alloc() and dma_direct_free() to apply set_memory_*() to the linear-map alias of the backing pages instead of the remapped CPU address. Also disallow highmem pages for __DMA_ATTR_ALLOC_CC_SHARED, because highmem buffers do not provide a usable linear-map address. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-19-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHAREDAneesh Kumar K.V (Arm)1-22/+30
Teach dma_direct_map_phys() to select the DMA address encoding based on DMA_ATTR_CC_SHARED. Use phys_to_dma_unencrypted() for decrypted mappings and phys_to_dma_encrypted() otherwise. If a device requires unencrypted DMA but the source physical address is still encrypted, force the mapping through swiotlb so the DMA address and backing memory attributes remain consistent. Update the arm64, x86, s390 and powerpc secure-guest setup to not use swiotlb force option Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-18-aneesh.kumar@kernel.org [mszyprow: rebased onto latest changes in arch/arm64/mm/init.c] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: Move dma_direct_map_phys() to dma/direct.cAneesh Kumar K.V (Arm)1-0/+53
dma_direct_map_phys() is too large to benefit from being inlined. Move its implementation to direct.c and leave the declaration in direct.h. No functional change in this patch Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-17-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-mapping: make dma_pgprot() honor __DMA_ATTR_ALLOC_CC_SHAREDAneesh Kumar K.V (Arm)1-5/+3
Fold encrypted/decrypted pgprot selection into dma_pgprot() so callers do not need to adjust the page protection separately. Update dma_pgprot() to apply pgprot_decrypted() when DMA_ATTR_CC_SHARED or __DMA_ATTR_ALLOC_CC_SHARED is set and pgprot_encrypted() otherwise Convert the dma-direct mmap paths to pass DMA_ATTR_CC_SHARED instead of open-coding force_dma_unencrypted() handling around dma_pgprot(). Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-15-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHAREDAneesh Kumar K.V (Arm)1-4/+9
Teach swiotlb to distinguish between encrypted and decrypted bounce buffer pools, and make allocation and mapping paths select a pool whose state matches the requested DMA attributes. Add a cc_shared flag to io_tlb_mem, initialize it for the default and restricted pools, and propagate __DMA_ATTR_ALLOC_CC_SHARED into swiotlb pool allocation. Reject swiotlb alloc/map requests when the selected pool does not match the required encrypted/decrypted state. Also return DMA addresses with the matching phys_to_dma_{encrypted, unencrypted} helper so the DMA address encoding stays consistent with the chosen pool. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-14-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-pool: track decrypted atomic pools and select them via attrsAneesh Kumar K.V (Arm)1-4/+10
Teach the atomic DMA pool code to distinguish between encrypted and unencrypted pools, and make pool allocation select the matching pool based on DMA attributes. Introduce a dma_gen_pool wrapper that records whether a pool is unencrypted, initialize that state when the atomic pools are created, and use it when expanding and resizing the pools. Update dma_alloc_from_pool() to take attrs and skip pools whose encrypted state does not match __DMA_ATTR_ALLOC_CC_SHARED. Update dma_free_from_pool() accordingly. Also pass __DMA_ATTR_ALLOC_CC_SHARED from the swiotlb atomic allocation path so decrypted swiotlb allocations are taken from the correct atomic pool. Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-12-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free pathsAneesh Kumar K.V (Arm)1-9/+33
Propagate force_dma_unencrypted() into __DMA_ATTR_ALLOC_CC_SHARED in the dma-direct allocation path and use the attribute to drive the related decisions. This updates dma_direct_alloc(), dma_direct_free(), and dma_direct_alloc_pages() to fold the forced unencrypted case into attrs. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-11-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pagesAneesh Kumar K.V (Arm)1-18/+53
Move swiotlb allocation out of __dma_direct_alloc_pages() and handle it in dma_direct_alloc() / dma_direct_alloc_pages(). This is needed for follow-up changes that simplify the handling of memory encryption/decryption based on the DMA attribute flags. swiotlb backing pages are already mapped decrypted by swiotlb_update_mem_attributes() and rmem_swiotlb_device_init(), so dma-direct should not call dma_set_decrypted() on allocation nor dma_set_encrypted() on free for swiotlb-backed memory. Update alloc/free paths to detect swiotlb-backed pages and skip encrypt/decrypt transitions for those paths. Keep the existing highmem rejection in dma_direct_alloc_pages() for swiotlb allocations. Only for "restricted-dma-pool", we currently set `for_alloc = true`, while rmem_swiotlb_device_init() decrypts the whole pool up front. This pool is typically used together with "shared-dma-pool", where the shared region is accessed after remap/ioremap and the returned address is suitable for decrypted memory access. So existing code paths remain valid. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-8-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: free atomic pool pages by physical addressAneesh Kumar K.V (Arm)1-2/+2
dma_direct_alloc_pages() may satisfy atomic allocations from the coherent atomic pools. The pool allocation is keyed by the virtual address stored in the gen_pool, but the pages API returns only the backing struct page. On architectures with CONFIG_DMA_DIRECT_REMAP, atomic pool chunks are added to the gen_pool using their remapped virtual address. dma_direct_free_pages() reconstructs a linear-map address with page_address(page) and passes that to dma_free_from_pool(). That address does not match the gen_pool virtual range, so the pool lookup can fail and the code can fall through to freeing a pool-owned page through the normal page allocator path. Add a page-based pool free helper that looks up the owning pool chunk by physical address, translates it back to the gen_pool virtual address, and frees that address to the pool. Use it from dma_direct_free_pages() while keeping the existing virtual-address helper for coherent allocation frees. Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-5-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: return struct page from dma_direct_alloc_from_pool()Aneesh Kumar K.V (Arm)1-8/+10
Commit 5b138c534fda ("dma-direct: factor out a dma_direct_alloc_from_pool helper") changed dma_direct_alloc_from_pool() to return the CPU address from dma_alloc_from_pool(). That fits dma_direct_alloc(), but dma_direct_alloc_pages() also uses the helper and expects a struct page *. Fix this by making dma_direct_alloc_from_pool() return the struct page * again, and pass the CPU address back through an out-parameter for the dma_direct_alloc() caller. Fixes: 5b138c534fda ("dma-direct: factor out a dma_direct_alloc_from_pool helper") Cc: stable@vger.kernel.org Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-2-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-14dma-direct: Improve readability of the dma_direct_map_sg() for P2PDMA caseMarek Szyprowski1-2/+1
Improve readability of the sg_dma_len assignment in the P2PDMA cases by removing duplicated code, which was a direct result of the d0d08f4bd7f6 ("dma-direct: Fix missing sg_dma_len assignment in P2PDMA bus mappings") fix. No functional change. Suggested-by: Leon Romanovsky <leon@kernel.org> Link: https://lore.kernel.org/all/20260604071856.GA245424@unreal/ Reviewed-by: Pranjal Shrivastava <praan@google.com> Reviewed-by: Leon Romanovsky <leon@kernel.org> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/20260713083022.1110993-1-m.szyprowski@samsung.com Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-06-03dma-mapping: direct: fix missing mapping for THRU_HOST_BRIDGE segmentsLi RongQing1-1/+1
In dma_direct_map_sg(), the case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE incorrectly used 'break' instead of falling through to MAP_NONE. As a result, segments traversing the host bridge skipped the required dma_direct_map_phys() call entirely, leaving sg->dma_address uninitialized and leading to DMA failures. Fix this by using 'fallthrough;'. Fixes: a25e7962db0d79 ("PCI/P2PDMA: Refactor the p2pdma mapping helpers") Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20260603013723.2439-1-lirongqing@baidu.com
2026-04-30dma-direct: fix use of max_pfnPetr Tesarik1-2/+2
Calculate the correct physical address of the last byte of memory. Since max_pfn is in fact "the PFN of the first page after the highest system RAM in physical address space", the highest address that might be used for a DMA buffer is one byte below max_pfn << PAGE_SHIFT. This fix is unlikely to make any difference in practice. It's just that the current formula is slightly confusing. Signed-off-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20260410113506.262579-1-ptesarik@suse.com
2026-03-13dma-mapping: Support batch mode for dma_direct_{map,unmap}_sgBarry Song1-4/+13
Extending these APIs with a flush argument: dma_direct_unmap_phys(), dma_direct_map_phys(), and dma_direct_sync_single_for_cpu(). For single-buffer cases, flush=true would be used, while for SG cases flush=false would be used, followed by a single flush after all cache operations are issued in dma_direct_{map,unmap}_sg(). This ultimately benefits dma_map_sg() and dma_unmap_sg(). Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Ada Couprie Diaz <ada.coupriediaz@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tangquan Zheng <zhengtangquan@oppo.com> Reviewed-by: Leon Romanovsky <leon@kernel.org> Tested-by: Xueyuan Chen <xueyuan.chen21@gmail.com> Signed-off-by: Barry Song <baohua@kernel.org> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20260228221337.59951-1-21cnbao@gmail.com
2026-03-13dma-mapping: Separate DMA sync issuing and completion waitingBarry Song1-1/+5
Currently, arch_sync_dma_for_cpu and arch_sync_dma_for_device always wait for the completion of each DMA buffer. That is, issuing the DMA sync and waiting for completion is done in a single API call. For scatter-gather lists with multiple entries, this means issuing and waiting is repeated for each entry, which can hurt performance. Architectures like ARM64 may be able to issue all DMA sync operations for all entries first and then wait for completion together. To address this, arch_sync_dma_for_* now batches DMA operations and performs a flush afterward. On ARM64, the flush is implemented with a dsb instruction in arch_sync_dma_flush(). On other architectures, arch_sync_dma_flush() is currently a nop. Cc: Leon Romanovsky <leon@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Ada Couprie Diaz <ada.coupriediaz@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Tangquan Zheng <zhengtangquan@oppo.com> Reviewed-by: Juergen Gross <jgross@suse.com> # drivers/xen/swiotlb-xen.c Tested-by: Xueyuan Chen <xueyuan.chen21@gmail.com> Signed-off-by: Barry Song <baohua@kernel.org> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20260228221316.59934-1-21cnbao@gmail.com
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds1-1/+1
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook1-1/+1
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-01-08dma-mapping: Remove dma_mark_clean (again)Robin Murphy1-3/+0
With IA-64 now gone, there are no users of the dma_mark_clean hook, so we can retire it for good. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/c004927f01962726ff1dcf94d1b4efff84db805a.1767727673.git.robin.murphy@arm.com
2025-12-04Merge tag 'vfio-v6.19-rc1' of https://github.com/awilliam/linux-vfioLinus Torvalds1-2/+2
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 ...
2025-11-26dma-direct: Fix missing sg_dma_len assignment in P2PDMA bus mappingsPranjal Shrivastava1-0/+1
Prior to commit a25e7962db0d7 ("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: a25e7962db0d7 ("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
2025-11-20PCI/P2PDMA: Simplify bus address mapping APILeon Romanovsky1-2/+2
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>
2025-09-12dma-mapping: export new dma_*map_phys() interfaceLeon Romanovsky1-16/+0
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
2025-09-12dma-mapping: convert dma_direct_*map_page to be phys_addr_t basedLeon Romanovsky1-3/+3
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
2025-08-11dma-direct: clean up the logic in __dma_direct_alloc_pages()Petr Tesarik1-18/+13
Convert a goto-based loop to a while() loop. To allow the simplification, return early when allocation from CMA is successful. As a bonus, this early return avoids a repeated dma_coherent_ok() check. No functional change. Signed-off-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20250710083829.1853466-1-ptesarik@suse.com
2025-05-06dma-mapping: move the PCI P2PDMA mapping helpers to pci-p2pdma.hChristoph Hellwig1-0/+1
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>
2025-05-06PCI/P2PDMA: Refactor the p2pdma mapping helpersChristoph Hellwig1-22/+21
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>
2025-03-12dma-mapping: fix missing clear bdr in check_ram_in_range_map()Baochen Qiang1-10/+18
As discussed in [1], if 'bdr' is set once, it would never get cleared, hence 0 is always returned. Refactor the range check hunk into a new helper dma_find_range(), which allows 'bdr' to be cleared in each iteration. Link: https://lore.kernel.org/all/64931fac-085b-4ff3-9314-84bac2fa9bdb@quicinc.com/ # [1] Fixes: a409d9600959 ("dma-mapping: fix dma_addressing_limited() if dma_range_map can't cover all system RAM") Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com> Link: https://lore.kernel.org/r/20250307030350.69144-1-quic_bqiang@quicinc.com Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2024-09-04dma-direct: optimize page freeing when it is not addressableChen Yu1-1/+1
When the CMA allocation succeeds but isn't addressable, its buffer has already been released and the page is set to NULL. So later when the normal page allocation succeeds but isn't addressable, __free_pages() can be used to free that normal page rather than using dma_free_contiguous that does extra checks that are not needed. Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-08-22dma-mapping: replace zone_dma_bits by zone_dma_limitCatalin Marinas1-3/+3
The hardware DMA limit might not be power of 2. When RAM range starts above 0, say 4GB, DMA limit of 30 bits should end at 5GB. A single high bit can not encode this limit. Use a plain address for the DMA zone limit instead. Since the DMA zone can now potentially span beyond 4GB physical limit of DMA32, make sure to use DMA zone for GFP_DMA32 allocations in that case. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Co-developed-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Baruch Siach <baruch@tkos.co.il> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-07-10swiotlb: reduce swiotlb pool lookupsMichael Kelley1-7/+3
With CONFIG_SWIOTLB_DYNAMIC enabled, each round-trip map/unmap pair in the swiotlb results in 6 calls to swiotlb_find_pool(). In multiple places, the pool is found and used in one function, and then must be found again in the next function that is called because only the tlb_addr is passed as an argument. These are the six call sites: dma_direct_map_page: 1. swiotlb_map -> swiotlb_tbl_map_single -> swiotlb_bounce dma_direct_unmap_page: 2. dma_direct_sync_single_for_cpu -> is_swiotlb_buffer 3. dma_direct_sync_single_for_cpu -> swiotlb_sync_single_for_cpu -> swiotlb_bounce 4. is_swiotlb_buffer 5. swiotlb_tbl_unmap_single -> swiotlb_del_transient 6. swiotlb_tbl_unmap_single -> swiotlb_release_slots Reduce the number of calls by finding the pool at a higher level, and passing it as an argument instead of searching again. A key change is for is_swiotlb_buffer() to return a pool pointer instead of a boolean, and then pass this pool pointer to subsequent swiotlb functions. There are 9 occurrences of is_swiotlb_buffer() used to test if a buffer is a swiotlb buffer before calling a swiotlb function. To reduce code duplication in getting the pool pointer and passing it as an argument, introduce inline wrappers for this pattern. The generated code is essentially unchanged. Since is_swiotlb_buffer() no longer returns a boolean, rename some functions to reflect the change: * swiotlb_find_pool() becomes __swiotlb_find_pool() * is_swiotlb_buffer() becomes swiotlb_find_pool() * is_xen_swiotlb_buffer() becomes xen_swiotlb_find_pool() With these changes, a round-trip map/unmap pair requires only 2 pool lookups (listed using the new names and wrappers): dma_direct_unmap_page: 1. dma_direct_sync_single_for_cpu -> swiotlb_find_pool 2. swiotlb_tbl_unmap_single -> swiotlb_find_pool These changes come from noticing the inefficiencies in a code review, not from performance measurements. With CONFIG_SWIOTLB_DYNAMIC, __swiotlb_find_pool() is not trivial, and it uses an RCU read lock, so avoiding the redundant calls helps performance in a hot path. When CONFIG_SWIOTLB_DYNAMIC is *not* set, the code size reduction is minimal and the perf benefits are likely negligible, but no harm is done. No functional change is intended. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Petr Tesarik <petr@tesarici.cz> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-02-28dma-direct: Leak pages on dma_set_decrypted() failureRick Edgecombe1-4/+5
On TDX it is possible for the untrusted host to cause set_memory_encrypted() or set_memory_decrypted() to fail such that an error is returned and the resulting memory is shared. Callers need to take care to handle these errors to avoid returning decrypted (shared) memory to the page allocator, which could lead to functional or security issues. DMA could free decrypted/shared pages if dma_set_decrypted() fails. This should be a rare case. Just leak the pages in this case instead of freeing them. Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-12-15dma-mapping: don't store redundant offsetsRobin Murphy1-1/+0
A bus_dma_region necessarily stores both CPU and DMA base addresses for a range, so there's no need to also store the difference between them. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-11-06dma-mapping: fix dma_addressing_limited() if dma_range_map can't cover all ↵Jia He1-0/+40
system RAM There is an unusual case that the range map covers right up to the top of system RAM, but leaves a hole somewhere lower down. Then it prevents the nvme device dma mapping in the checking path of phys_to_dma() and causes the hangs at boot. E.g. On an Armv8 Ampere server, the dsdt ACPI table is: Method (_DMA, 0, Serialized) // _DMA: Direct Memory Access { Name (RBUF, ResourceTemplate () { QWordMemory (ResourceConsumer, PosDecode, MinFixed, MaxFixed, Cacheable, ReadWrite, 0x0000000000000000, // Granularity 0x0000000000000000, // Range Minimum 0x00000000FFFFFFFF, // Range Maximum 0x0000000000000000, // Translation Offset 0x0000000100000000, // Length ,, , AddressRangeMemory, TypeStatic) QWordMemory (ResourceConsumer, PosDecode, MinFixed, MaxFixed, Cacheable, ReadWrite, 0x0000000000000000, // Granularity 0x0000006010200000, // Range Minimum 0x000000602FFFFFFF, // Range Maximum 0x0000000000000000, // Translation Offset 0x000000001FE00000, // Length ,, , AddressRangeMemory, TypeStatic) QWordMemory (ResourceConsumer, PosDecode, MinFixed, MaxFixed, Cacheable, ReadWrite, 0x0000000000000000, // Granularity 0x00000060F0000000, // Range Minimum 0x00000060FFFFFFFF, // Range Maximum 0x0000000000000000, // Translation Offset 0x0000000010000000, // Length ,, , AddressRangeMemory, TypeStatic) QWordMemory (ResourceConsumer, PosDecode, MinFixed, MaxFixed, Cacheable, ReadWrite, 0x0000000000000000, // Granularity 0x0000007000000000, // Range Minimum 0x000003FFFFFFFFFF, // Range Maximum 0x0000000000000000, // Translation Offset 0x0000039000000000, // Length ,, , AddressRangeMemory, TypeStatic) }) But the System RAM ranges are: cat /proc/iomem |grep -i ram 90000000-91ffffff : System RAM 92900000-fffbffff : System RAM 880000000-fffffffff : System RAM 8800000000-bff5990fff : System RAM bff59d0000-bff5a4ffff : System RAM bff8000000-bfffffffff : System RAM So some RAM ranges are out of dma_range_map. Fix it by checking whether each of the system RAM resources can be properly encompassed within the dma_range_map. Signed-off-by: Jia He <justin.he@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-10-22dma-direct: warn when coherent allocations aren't supportedChristoph Hellwig1-1/+3
Log a warning once when dma_alloc_coherent fails because the platform does not support coherent allocations at all. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Tested-by: Greg Ungerer <gerg@linux-m68k.org>
2023-10-22dma-direct: simplify the use atomic pool logic in dma_direct_allocChristoph Hellwig1-15/+10
The logic in dma_direct_alloc when to use the atomic pool vs remapping grew a bit unreadable. Consolidate it into a single check, and clean up the set_uncached vs remap logic a bit as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Tested-by: Greg Ungerer <gerg@linux-m68k.org>
2023-10-22dma-direct: add a CONFIG_ARCH_HAS_DMA_ALLOC symbolChristoph Hellwig1-10/+2
Instead of using arch_dma_alloc if none of the generic coherent allocators are used, require the architectures to explicitly opt into providing it. This will used to deal with the case of m68knommu and coldfire where we can't do any coherent allocations whatsoever, and also makes it clear that arch_dma_alloc is a last resort. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Tested-by: Greg Ungerer <gerg@linux-m68k.org>
2023-08-01swiotlb: if swiotlb is full, fall back to a transient memory poolPetr Tesarik1-1/+1
Try to allocate a transient memory pool if no suitable slots can be found and the respective SWIOTLB is allowed to grow. The transient pool is just enough big for this one bounce buffer. It is inserted into a per-device list of transient memory pools, and it is freed again when the bounce buffer is unmapped. Transient memory pools are kept in an RCU list. A memory barrier is required after adding a new entry, because any address within a transient buffer must be immediately recognized as belonging to the SWIOTLB, even if it is passed to another CPU. Deletion does not require any synchronization beyond RCU ordering guarantees. After a buffer is unmapped, its physical addresses may no longer be passed to the DMA API, so the memory range of the corresponding stale entry in the RCU list never matches. If the memory range gets allocated again, then it happens only after a RCU quiescent state. Since bounce buffers can now be allocated from different pools, add a parameter to swiotlb_alloc_pool() to let the caller know which memory pool is used. Add swiotlb_find_pool() to find the memory pool corresponding to an address. This function is now also used by is_swiotlb_buffer(), because a simple boundary check is no longer sufficient. The logic in swiotlb_alloc_tlb() is taken from __dma_direct_alloc_pages(), simplified and enhanced to use coherent memory pools if needed. Note that this is not the most efficient way to provide a bounce buffer, but when a DMA buffer can't be mapped, something may (and will) actually break. At that point it is better to make an allocation, even if it may be an expensive operation. Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-06-19dma-mapping: name SG DMA flag helpers consistentlyRobin Murphy1-1/+1
sg_is_dma_bus_address() is inconsistent with the naming pattern of its corresponding setters and its own kerneldoc, so take the majority vote and rename it sg_dma_is_bus_address() (and fix up the missing underscores in the kerneldoc too). This gives us a nice clear pattern where SG DMA flags are SG_DMA_<NAME>, and the helpers for acting on them are sg_dma_<action>_<name>(). Link: https://lkml.kernel.org/r/20230612153201.554742-14-catalin.marinas@arm.com Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/fa2eca2862c7ffc41b50337abffb2dfd2864d3ea.1685036694.git.robin.murphy@arm.com Tested-by: Isaac J. Manjarres <isaacmanjarres@google.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Joerg Roedel <joro@8bytes.org> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Mike Snitzer <snitzer@kernel.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-28dma-direct: cleanup parameters to dma_direct_optimal_gfp_maskPetr Tesarik1-8/+7
Since both callers of dma_direct_optimal_gfp_mask() pass dev->coherent_dma_mask as the second argument, it is better to remove that parameter altogether. Not only is reducing number of parameters good for readability, but the new function signature is also more logical: The optimal flags depend only on data contained in struct device. While touching this code, let's also rename phys_mask to phys_limit in dma_direct_alloc_from_pool(), because it is indeed a limit. Signed-off-by: Petr Tesarik <petrtesarik@huaweicloud.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-08-06Merge tag 'dma-mapping-5.20-2022-08-06' of ↵Linus Torvalds1-6/+37
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 ...
2022-07-26dma-direct: support PCI P2PDMA pages in dma-direct map_sgLogan Gunthorpe1-6/+37
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>
2022-06-23dma-direct: use the correct size for dma_set_encrypted()Dexuan Cui1-3/+2
The third parameter of dma_set_encrypted() is a size in bytes rather than the number of pages. Fixes: 4d0564785bb0 ("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>
2022-05-23dma-direct: don't over-decrypt memoryRobin Murphy1-2/+2
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: c10f07aa27da ("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>
2022-05-11dma-direct: don't fail on highmem CMA pages in dma_direct_alloc_pagesChristoph Hellwig1-17/+10
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: efa70f2fdc84 ("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>
2022-04-01dma-mapping: move pgprot_decrypted out of dma_pgprotChristoph Hellwig1-2/+8
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: f5ff79fddf0e ("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>
2022-03-03dma-mapping: remove CONFIG_DMA_REMAPChristoph Hellwig1-11/+7
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>