Commit graph

74 commits

Author SHA1 Message Date
Jia He
8ae0e97031 dma-mapping: move dma_addressing_limited() out of line
This patch moves dma_addressing_limited() out of line, serving as a
preliminary step to prevent the introduction of a new publicly accessible
low-level helper when validating whether all system RAM is mapped within
the DMA mapping range.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jia He <justin.he@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-11-06 08:35:09 +01:00
Arnd Bergmann
3d6f126b15 dma-mapping: move arch_dma_set_mask() declaration to header
This function has a __weak definition and an override that is only used on
freescale powerpc chips. The powerpc definition however does not see the
declaration that is in a .c file:

arch/powerpc/kernel/dma-mask.c:7:6: error: no previous prototype for 'arch_dma_set_mask' [-Werror=missing-prototypes]

Move it into the linux/dma-map-ops.h header where the other arch_dma_* functions
are declared.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-07-31 17:54:28 +02:00
Jiaxun Yang
1d3f56b295 dma-mapping: provide CONFIG_ARCH_DMA_DEFAULT_COHERENT
Provide a kconfig option to allow arches to manipulate default
value of dma_default_coherent in Kconfig.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-04-07 07:38:25 +02:00
Jiaxun Yang
fe4e5efa40 dma-mapping: provide a fallback dma_default_coherent
dma_default_coherent was decleared unconditionally at kernel/dma/mapping.c
but only decleared when any of non-coherent options is enabled in
dma-map-ops.h.

Guard the declaration in mapping.c with non-coherent options and provide
a fallback definition.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-04-07 07:38:20 +02:00
Christoph Hellwig
3622b86f49 dma-mapping: reject GFP_COMP for noncoherent allocations
While not quite as bogus as for the dma-coherent allocations that were
fixed earlier, GFP_COMP for these allocations has no benefits for
the dma-direct case, and can't be supported at all by dma dma-iommu
backend which splits up allocations into smaller orders.  Due to an
oversight in ffcb754584 that flag stopped being cleared for all
dma allocations, but only got rejected for coherent ones, so fix up
these callers to not allow __GFP_COMP as well after the sound code
has been fixed to not ask for it.

Fixes: ffcb754584 ("dma-mapping: reject __GFP_COMP in dma_alloc_attrs")
Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reported-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Tested-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
2022-12-21 08:45:38 +01:00
Christoph Hellwig
ffcb754584 dma-mapping: reject __GFP_COMP in dma_alloc_attrs
DMA allocations can never be turned back into a page pointer, so
requesting compound pages doesn't make sense and it can't even be
supported at all by various backends.

Reject __GFP_COMP with a warning in dma_alloc_attrs, and stop clearing
the flag in the arm dma ops and dma-iommu.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
2022-11-21 09:37:20 +01:00
Linus Torvalds
27bc50fc90 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
linux-next for a couple of months without, to my knowledge, any negative
   reports (or any positive ones, come to that).
 
 - Also the Maple Tree from Liam R.  Howlett.  An overlapping range-based
   tree for vmas.  It it apparently slight more efficient in its own right,
   but is mainly targeted at enabling work to reduce mmap_lock contention.
 
   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.
 
   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   (https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com).
   This has yet to be addressed due to Liam's unfortunately timed
   vacation.  He is now back and we'll get this fixed up.
 
 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer.  It uses
   clang-generated instrumentation to detect used-unintialized bugs down to
   the single bit level.
 
   KMSAN keeps finding bugs.  New ones, as well as the legacy ones.
 
 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.
 
 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support
   file/shmem-backed pages.
 
 - userfaultfd updates from Axel Rasmussen
 
 - zsmalloc cleanups from Alexey Romanov
 
 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure
 
 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.
 
 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.
 
 - memcg cleanups from Kairui Song.
 
 - memcg fixes and cleanups from Johannes Weiner.
 
 - Vishal Moola provides more folio conversions
 
 - Zhang Yi removed ll_rw_block() :(
 
 - migration enhancements from Peter Xu
 
 - migration error-path bugfixes from Huang Ying
 
 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths.  For optimizations by PMEM drivers, DRM
   drivers, etc.
 
 - vma merging improvements from Jakub Matěn.
 
 - NUMA hinting cleanups from David Hildenbrand.
 
 - xu xin added aditional userspace visibility into KSM merging activity.
 
 - THP & KSM code consolidation from Qi Zheng.
 
 - more folio work from Matthew Wilcox.
 
 - KASAN updates from Andrey Konovalov.
 
 - DAMON cleanups from Kaixu Xia.
 
 - DAMON work from SeongJae Park: fixes, cleanups.
 
 - hugetlb sysfs cleanups from Muchun Song.
 
 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.
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Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
   linux-next for a couple of months without, to my knowledge, any
   negative reports (or any positive ones, come to that).

 - Also the Maple Tree from Liam Howlett. An overlapping range-based
   tree for vmas. It it apparently slightly more efficient in its own
   right, but is mainly targeted at enabling work to reduce mmap_lock
   contention.

   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.

   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   at [1]. This has yet to be addressed due to Liam's unfortunately
   timed vacation. He is now back and we'll get this fixed up.

 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
   clang-generated instrumentation to detect used-unintialized bugs down
   to the single bit level.

   KMSAN keeps finding bugs. New ones, as well as the legacy ones.

 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.

 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
   support file/shmem-backed pages.

 - userfaultfd updates from Axel Rasmussen

 - zsmalloc cleanups from Alexey Romanov

 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
   memory-failure

 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.

 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.

 - memcg cleanups from Kairui Song.

 - memcg fixes and cleanups from Johannes Weiner.

 - Vishal Moola provides more folio conversions

 - Zhang Yi removed ll_rw_block() :(

 - migration enhancements from Peter Xu

 - migration error-path bugfixes from Huang Ying

 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths. For optimizations by PMEM drivers, DRM
   drivers, etc.

 - vma merging improvements from Jakub Matěn.

 - NUMA hinting cleanups from David Hildenbrand.

 - xu xin added aditional userspace visibility into KSM merging
   activity.

 - THP & KSM code consolidation from Qi Zheng.

 - more folio work from Matthew Wilcox.

 - KASAN updates from Andrey Konovalov.

 - DAMON cleanups from Kaixu Xia.

 - DAMON work from SeongJae Park: fixes, cleanups.

 - hugetlb sysfs cleanups from Muchun Song.

 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
  hugetlb: allocate vma lock for all sharable vmas
  hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer
  hugetlb: fix vma lock handling during split vma and range unmapping
  mglru: mm/vmscan.c: fix imprecise comments
  mm/mglru: don't sync disk for each aging cycle
  mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
  mm: memcontrol: use do_memsw_account() in a few more places
  mm: memcontrol: deprecate swapaccounting=0 mode
  mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
  mm/secretmem: remove reduntant return value
  mm/hugetlb: add available_huge_pages() func
  mm: remove unused inline functions from include/linux/mm_inline.h
  selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
  selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
  selftests/vm: add thp collapse shmem testing
  selftests/vm: add thp collapse file and tmpfs testing
  selftests/vm: modularize thp collapse memory operations
  selftests/vm: dedup THP helpers
  mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
  mm/madvise: add file and shmem support to MADV_COLLAPSE
  ...
2022-10-10 17:53:04 -07:00
Alexander Potapenko
7ade4f1077 dma: kmsan: unpoison DMA mappings
KMSAN doesn't know about DMA memory writes performed by devices.  We
unpoison such memory when it's mapped to avoid false positive reports.

Link: https://lkml.kernel.org/r/20220915150417.722975-22-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:21 -07:00
Christoph Hellwig
9fc18f6d56 dma-mapping: mark dma_supported static
Now that the remaining users in drivers are gone, this function can be
marked static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-07 10:38:28 +02:00
Logan Gunthorpe
8419702489 dma-mapping: reformat comment to suppress htmldoc warning
make html doc reports a cryptic warning with the commit named below:

  kernel/dma/mapping.c:258: WARNING: Option list ends without a blank
                                     line; unexpected unindent.

Seems the parser is a bit fussy about the tabbing and having a single
space tab causes the warning. To suppress the warning add another
tab to the list and reindent everything.

Fixes: 7c2645a2a3 ("dma-mapping: allow EREMOTEIO return code for P2PDMA transfers")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-28 07:21:33 -07:00
Logan Gunthorpe
159bf19270 dma-mapping: add flags to dma_map_ops to indicate PCI P2PDMA support
Add a flags member to the dma_map_ops structure with one flag to
indicate support for PCI P2PDMA.

Also, add a helper to check if a device supports PCI P2PDMA.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-26 07:27:48 -04:00
Logan Gunthorpe
7c2645a2a3 dma-mapping: allow EREMOTEIO return code for P2PDMA transfers
Add EREMOTEIO error return to dma_map_sgtable() which will be used
by .map_sg() implementations that detect P2PDMA pages that the
underlying DMA device cannot access.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-26 07:27:47 -04:00
John Garry
a229cc14f3 dma-mapping: add dma_opt_mapping_size()
Streaming DMA mapping involving an IOMMU may be much slower for larger
total mapping size. This is because every IOMMU DMA mapping requires an
IOVA to be allocated and freed. IOVA sizes above a certain limit are not
cached, which can have a big impact on DMA mapping performance.

Provide an API for device drivers to know this "optimal" limit, such that
they may try to produce mapping which don't exceed it.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-19 06:05:41 +02:00
Christoph Hellwig
4fe87e818e dma-mapping: move pgprot_decrypted out of dma_pgprot
pgprot_decrypted is used by AMD SME systems to allow access to memory
that was set to not encrypted using set_memory_decrypted.  That only
happens for dma-direct memory as the IOMMU solves the addressing
challenges for the encryption bit using its own remapping.

Move the pgprot_decrypted call out of dma_pgprot which is also used
by the IOMMU mappings and into dma-direct so that it is only used with
memory that was set decrypted.

Fixes: f5ff79fddf ("dma-mapping: remove CONFIG_DMA_REMAP")
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
2022-04-01 06:46:51 +02:00
Linus Walleij
00ba9357d1 ARM: ixp4xx: Drop custom DMA coherency and bouncing
The new PCI driver does not need any of this stuff, so just
drop it.

Cc: iommu@lists.linux-foundation.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220211223238.648934-12-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2022-02-12 18:20:04 +01:00
Linus Torvalds
46f8763228 arm64 updates for 5.16
- Support for the Arm8.6 timer extensions, including a self-synchronising
   view of the system registers to elide some expensive ISB instructions.
 
 - Exception table cleanup and rework so that the fixup handlers appear
   correctly in backtraces.
 
 - A handful of miscellaneous changes, the main one being selection of
   CONFIG_HAVE_POSIX_CPU_TIMERS_TASK_WORK.
 
 - More mm and pgtable cleanups.
 
 - KASAN support for "asymmetric" MTE, where tag faults are reported
   synchronously for loads (via an exception) and asynchronously for
   stores (via a register).
 
 - Support for leaving the MMU enabled during kexec relocation, which
   significantly speeds up the operation.
 
 - Minor improvements to our perf PMU drivers.
 
 - Improvements to the compat vDSO build system, particularly when
   building with LLVM=1.
 
 - Preparatory work for handling some Coresight TRBE tracing errata.
 
 - Cleanup and refactoring of the SVE code to pave the way for SME
   support in future.
 
 - Ensure SCS pages are unpoisoned immediately prior to freeing them
   when KASAN is enabled for the vmalloc area.
 
 - Try moving to the generic pfn_valid() implementation again now that
   the DMA mapping issue from last time has been resolved.
 
 - Numerous improvements and additions to our FPSIMD and SVE selftests.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "There's the usual summary below, but the highlights are support for
  the Armv8.6 timer extensions, KASAN support for asymmetric MTE, the
  ability to kexec() with the MMU enabled and a second attempt at
  switching to the generic pfn_valid() implementation.

  Summary:

   - Support for the Arm8.6 timer extensions, including a
     self-synchronising view of the system registers to elide some
     expensive ISB instructions.

   - Exception table cleanup and rework so that the fixup handlers
     appear correctly in backtraces.

   - A handful of miscellaneous changes, the main one being selection of
     CONFIG_HAVE_POSIX_CPU_TIMERS_TASK_WORK.

   - More mm and pgtable cleanups.

   - KASAN support for "asymmetric" MTE, where tag faults are reported
     synchronously for loads (via an exception) and asynchronously for
     stores (via a register).

   - Support for leaving the MMU enabled during kexec relocation, which
     significantly speeds up the operation.

   - Minor improvements to our perf PMU drivers.

   - Improvements to the compat vDSO build system, particularly when
     building with LLVM=1.

   - Preparatory work for handling some Coresight TRBE tracing errata.

   - Cleanup and refactoring of the SVE code to pave the way for SME
     support in future.

   - Ensure SCS pages are unpoisoned immediately prior to freeing them
     when KASAN is enabled for the vmalloc area.

   - Try moving to the generic pfn_valid() implementation again now that
     the DMA mapping issue from last time has been resolved.

   - Numerous improvements and additions to our FPSIMD and SVE
     selftests"

[ armv8.6 timer updates were in a shared branch and already came in
  through -tip in the timer pull  - Linus ]

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (85 commits)
  arm64: Select POSIX_CPU_TIMERS_TASK_WORK
  arm64: Document boot requirements for FEAT_SME_FA64
  arm64/sve: Fix warnings when SVE is disabled
  arm64/sve: Add stub for sve_max_virtualisable_vl()
  arm64: errata: Add detection for TRBE write to out-of-range
  arm64: errata: Add workaround for TSB flush failures
  arm64: errata: Add detection for TRBE overwrite in FILL mode
  arm64: Add Neoverse-N2, Cortex-A710 CPU part definition
  selftests: arm64: Factor out utility functions for assembly FP tests
  arm64: vmlinux.lds.S: remove `.fixup` section
  arm64: extable: add load_unaligned_zeropad() handler
  arm64: extable: add a dedicated uaccess handler
  arm64: extable: add `type` and `data` fields
  arm64: extable: use `ex` for `exception_table_entry`
  arm64: extable: make fixup_exception() return bool
  arm64: extable: consolidate definitions
  arm64: gpr-num: support W registers
  arm64: factor out GPR numbering helpers
  arm64: kvm: use kvm_exception_table_entry
  arm64: lib: __arch_copy_to_user(): fold fixups into body
  ...
2021-11-01 16:33:53 -07:00
Hamza Mahfooz
c2bbf9d1e9 dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC
Mapping something twice should be possible as long as,
DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant
mapping operation (that attempts to map the same thing). So, don't issue a
warning if the specified condition is met in add_dma_entry().

Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-10-18 12:46:45 +02:00
Logan Gunthorpe
011a9ce807 dma-mapping: fix the kerneldoc for dma_map_sgtable()
htmldocs began producing the following warnings:

  kernel/dma/mapping.c:256: WARNING: Definition list ends without a
             blank line; unexpected unindent.
  kernel/dma/mapping.c:257: WARNING: Bullet list ends without a blank
             line; unexpected unindent.

Reformatting the list without hyphens fixes the warnings and produces
both a readable text and HTML output.

Fixes: fffe3cc8c2 ("dma-mapping: allow map_sg() ops to return negative error code")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-10-11 13:43:04 +02:00
Mike Rapoport
a9c38c5d26 dma-mapping: remove bogus test for pfn_valid from dma_map_resource
dma_map_resource() uses pfn_valid() to ensure the range is not RAM.
However, pfn_valid() only checks for availability of the memory map for a
PFN but it does not ensure that the PFN is actually backed by RAM.

As dma_map_resource() is the only method in DMA mapping APIs that has this
check, simply drop the pfn_valid() test from dma_map_resource().

Link: https://lore.kernel.org/all/20210824173741.GC623@arm.com/
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210930013039.11260-2-rppt@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-01 14:54:45 +01:00
Christoph Hellwig
a61cb6017d dma-mapping: fix the kerneldoc for dma_map_sg_attrs
Add the missing description for the nents parameter, and fix a trivial
misalignment.

Fixes: fffe3cc8c2 ("dma-mapping: allow map_sg() ops to return negative error codes")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-09-06 14:40:47 +02:00
Christoph Hellwig
2a047e0662 dma-mapping: return an unsigned int from dma_map_sg{,_attrs}
These can only return 0 for failure or the number of entries, so turn
the return value into an unsigned int.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2021-08-14 09:18:36 +02:00
Logan Gunthorpe
d03c544192 dma-mapping: disallow .map_sg operations from returning zero on error
Now that all the .map_sg operations have been converted to returning
proper error codes, drop the code to handle a zero return value,
add a warning if a zero is returned.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-09 17:15:02 +02:00
Logan Gunthorpe
fffe3cc8c2 dma-mapping: allow map_sg() ops to return negative error codes
Allow dma_map_sgtable() to pass errors from the map_sg() ops. This
will be required for returning appropriate error codes when mapping
P2PDMA memory.

Introduce __dma_map_sg_attrs() which will return the raw error code
from the map_sg operation (whether it be negative or zero). Then add a
dma_map_sg_attrs() wrapper to convert any negative errors to zero to
satisfy the existing calling convention.

dma_map_sgtable() defines three error codes that .map_sg implementations
are allowed to return: -EINVAL, -ENOMEM and -EIO. The latter of which
is a generic return for cases that are passing DMA_MAPPING_ERROR
through.

dma_map_sgtable() will convert a zero error return for old map_sg() ops
into a -EIO return and return any negative errors as reported.

This allows map_sg implementations to start returning multiple
negative error codes. Legacy map_sg implementations can continue
to return zero until they are all converted.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-09 17:13:02 +02:00
Christoph Hellwig
7d5b5738d1 dma-mapping: add a dma_alloc_noncontiguous API
Add a new API that returns a potentiall virtually non-contigous sg_table
and a DMA address.  This API is only properly implemented for dma-iommu
and will simply return a contigious chunk as a fallback.

The intent is that drivers can use this API if either:

 - no kernel mapping or only temporary kernel mappings are required.
   That is as a better replacement for DMA_ATTR_NO_KERNEL_MAPPING
 - a kernel mapping is required for cached and DMA mapped pages, but
   the driver also needs the pages to e.g. map them to userspace.
   In that sense it is a replacement for some aspects of the recently
   removed and never fully implemented DMA_ATTR_NON_CONSISTENT

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>
2021-03-15 10:02:31 +01:00
Christoph Hellwig
198c50e2cc dma-mapping: refactor dma_{alloc,free}_pages
Factour out internal versions without the dma_debug calls in preparation
for callers that will need different dma_debug calls.

Note that this changes the dma_debug calls to get the not page aligned
size values, but as long as alloc and free agree on one variant we are
fine.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>
2021-03-15 10:02:31 +01:00
Christoph Hellwig
eedb0b12d0 dma-mapping: add a dma_mmap_pages helper
Add a helper to map memory allocated using dma_alloc_pages into
a user address space, similar to the dma_alloc_attrs function for
coherent allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>
2021-03-15 10:02:31 +01:00
Linus Torvalds
a4dec04c7f dma-mapping updates for 5.12:
- add support to emulate processing delays in the DMA API benchmark
    selftest (Barry Song)
  - remove support for non-contiguous noncoherent allocations,
    which aren't used and will be replaced by a different API
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Merge tag 'dma-mapping-5.12' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - add support to emulate processing delays in the DMA API benchmark
   selftest (Barry Song)

 - remove support for non-contiguous noncoherent allocations, which
   aren't used and will be replaced by a different API

* tag 'dma-mapping-5.12' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: remove the {alloc,free}_noncoherent methods
  dma-mapping: benchmark: pretend DMA is transmitting
2021-02-24 09:54:24 -08:00
Christoph Hellwig
6d4e9a8efe driver core: lift dma_default_coherent into common code
Lift the dma_default_coherent variable from the mips architecture code
to the driver core.  This allows an architecture to sdefault all device
to be DMA coherent at run time, even if the kernel is build with support
for DMA noncoherent device.  By allowing device_initialize to set the
->dma_coherent field to this default the amount of arch hooks required
for this behavior can be greatly reduced.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-02-13 09:51:45 +01:00
Christoph Hellwig
81d88ce550 dma-mapping: remove the {alloc,free}_noncoherent methods
It turns out allowing non-contigous allocations here was a rather bad
idea, as we'll now need to define ways to get the pages for mmaping
or dma_buf sharing.  Revert this change and stick to the original
concept.  A different API for the use case of non-contigous allocations
will be added back later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>:wq
2021-02-09 18:01:38 +01:00
Alexey Kardashevskiy
8d8d53cf8f dma-mapping: Allow mixing bypass and mapped DMA operation
At the moment we allow bypassing DMA ops only when we can do this for
the entire RAM. However there are configs with mixed type memory
where we could still allow bypassing IOMMU in most cases;
POWERPC with persistent memory is one example.

This adds an arch hook to determine where bypass can still work and
we invoke direct DMA API. The following patch checks the bus limit
on POWERPC to allow or disallow direct mapping.

This adds a ARCH_HAS_DMA_MAP_DIRECT config option to make the arch_xxxx
hooks no-op by default.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-11-27 10:33:40 +01:00
Christoph Hellwig
19c65c3d30 dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
Most of the dma_direct symbols should only be used by direct.c and
mapping.c, so move them to kernel/dma.  In fact more of dma-direct.h
should eventually move, but that will require more coordination with
other subsystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:06 +02:00
Christoph Hellwig
a1fd09e8e6 dma-mapping: move dma-debug.h to kernel/dma/
Most of dma-debug.h is not required by anything outside of kernel/dma.
Move the four declarations needed by dma-mappin.h or dma-ops providers
into dma-mapping.h and dma-map-ops.h, and move the remainder of the
file to kernel/dma/debug.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:05 +02:00
Christoph Hellwig
0a0f0d8be7 dma-mapping: split <linux/dma-mapping.h>
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers.  That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:03 +02:00
Christoph Hellwig
de7cf91776 dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
This will allow IOMMU drivers to allocate non-contigous memory and
return a vmapped virtual address.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-25 06:20:47 +02:00
Christoph Hellwig
efa70f2fdc dma-mapping: add a new dma_alloc_pages API
This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device.  The
implementation will also be used to provide a more sensible replacement
for DMA_ATTR_NON_CONSISTENT flag.

Additionally dma_alloc_noncoherent is switched over to use dma_alloc_pages
as its backend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
2020-09-25 06:20:47 +02:00
Christoph Hellwig
5a84292271 dma-mapping: remove dma_cache_sync
All users are gone now, remove the API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
2020-09-25 06:20:46 +02:00
Thomas Tai
f959dcd6dd dma-direct: Fix potential NULL pointer dereference
When booting the kernel v5.9-rc4 on a VM, the kernel would panic when
printing a warning message in swiotlb_map(). The dev->dma_mask must not
be a NULL pointer when calling the dma mapping layer. A NULL pointer
check can potentially avoid the panic.

Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-17 18:43:20 +02:00
Christoph Hellwig
545d29272f dma-mapping: move dma_common_{mmap,get_sgtable} out of mapping.c
Add a new file that contains helpers for misc DMA ops, which is only
built when CONFIG_DMA_OPS is set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-11 09:14:56 +02:00
Christoph Hellwig
d35834c648 dma-mapping: add a dma_ops_bypass flag to struct device
Several IOMMU drivers have a bypass mode where they can use a direct
mapping if the devices DMA mask is large enough.  Add generic support
to the core dma-mapping code to do that to switch those drivers to
a common solution.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2020-07-19 09:29:29 +02:00
Christoph Hellwig
d3fa60d7bf dma-mapping: move the remaining DMA API calls out of line
For a long time the DMA API has been implemented inline in dma-mapping.h,
but the function bodies can be quite large.  Move them all out of line.

This also removes all the dma_direct_* exports as those are just
implementation details and should never be used by drivers directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2020-07-16 16:58:33 +02:00
Christoph Hellwig
3aa9162500 dma-mapping: Add a new dma_need_sync API
Add a new API to check if calls to dma_sync_single_for_{device,cpu} are
required for a given DMA streaming mapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200629130359.2690853-2-hch@lst.de
2020-06-30 15:44:03 +02:00
Thomas Hellstrom
17c4a2ae15 dma-mapping: Fix dma_pgprot() for unencrypted coherent pages
When dma_mmap_coherent() sets up a mapping to unencrypted coherent memory
under SEV encryption and sometimes under SME encryption, it will actually
set up an encrypted mapping rather than an unencrypted, causing devices
that DMAs from that memory to read encrypted contents. Fix this.

When force_dma_unencrypted() returns true, the linear kernel map of the
coherent pages have had the encryption bit explicitly cleared and the
page content is unencrypted. Make sure that any additional PTEs we set
up to these pages also have the encryption bit cleared by having
dma_pgprot() return a protection with the encryption bit cleared in this
case.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lkml.kernel.org/r/20200304114527.3636-3-thomas_os@shipmail.org
2020-03-17 11:52:58 +01:00
Christoph Hellwig
34dc0ea6bc dma-direct: provide mmap and get_sgtable method overrides
For dma-direct we know that the DMA address is an encoding of the
physical address that we can trivially decode.  Use that fact to
provide implementations that do not need the arch_dma_coherent_to_pfn
architecture hook.  Note that we still can only support mmap of
non-coherent memory only if the architecture provides a way to set an
uncached bit in the page tables.  This must be true for architectures
that use the generic remap helpers, but other architectures can also
manually select it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
2019-11-11 10:52:15 +01:00
Linus Torvalds
45824fc0da powerpc updates for 5.4
- Initial support for running on a system with an Ultravisor, which is software
    that runs below the hypervisor and protects guests against some attacks by
    the hypervisor.
 
  - Support for building the kernel to run as a "Secure Virtual Machine", ie. as
    a guest capable of running on a system with an Ultravisor.
 
  - Some changes to our DMA code on bare metal, to allow devices with medium
    sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space.
 
  - Support for firmware assisted crash dumps on bare metal (powernv).
 
  - Two series fixing bugs in and refactoring our PCI EEH code.
 
  - A large series refactoring our exception entry code to use gas macros, both
    to make it more readable and also enable some future optimisations.
 
 As well as many cleanups and other minor features & fixups.
 
 Thanks to:
   Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh
   Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin
   Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy,
   Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens,
   David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar,
   Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari
   Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras,
   Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
   Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor,
   Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram
   Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj,
   Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung
   Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde.
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Merge tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "This is a bit late, partly due to me travelling, and partly due to a
  power outage knocking out some of my test systems *while* I was
  travelling.

   - Initial support for running on a system with an Ultravisor, which
     is software that runs below the hypervisor and protects guests
     against some attacks by the hypervisor.

   - Support for building the kernel to run as a "Secure Virtual
     Machine", ie. as a guest capable of running on a system with an
     Ultravisor.

   - Some changes to our DMA code on bare metal, to allow devices with
     medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of
     DMA space.

   - Support for firmware assisted crash dumps on bare metal (powernv).

   - Two series fixing bugs in and refactoring our PCI EEH code.

   - A large series refactoring our exception entry code to use gas
     macros, both to make it more readable and also enable some future
     optimisations.

  As well as many cleanups and other minor features & fixups.

  Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew
  Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual,
  Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe
  JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig,
  Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand,
  Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg
  Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim
  Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo
  Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
  Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver
  O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm,
  Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu,
  Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom
  Lendacky, Vasant Hegde"

* tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits)
  powerpc/mm/mce: Keep irqs disabled during lockless page table walk
  powerpc: Use ftrace_graph_ret_addr() when unwinding
  powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
  ftrace: Look up the address of return_to_handler() using helpers
  powerpc: dump kernel log before carrying out fadump or kdump
  docs: powerpc: Add missing documentation reference
  powerpc/xmon: Fix output of XIVE IPI
  powerpc/xmon: Improve output of XIVE interrupts
  powerpc/mm/radix: remove useless kernel messages
  powerpc/fadump: support holes in kernel boot memory area
  powerpc/fadump: remove RMA_START and RMA_END macros
  powerpc/fadump: update documentation about option to release opalcore
  powerpc/fadump: consider f/w load area
  powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file
  powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes
  powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP
  powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
  powerpc/fadump: improve how crashed kernel's memory is reserved
  powerpc/fadump: consider reserved ranges while releasing memory
  powerpc/fadump: make crash memory ranges array allocation generic
  ...
2019-09-20 11:48:06 -07:00
Christoph Hellwig
249baa5479 dma-mapping: provide a better default ->get_required_mask
Most dma_map_ops instances are IOMMUs that work perfectly fine in 32-bits
of IOVA space, and the generic direct mapping code already provides its
own routines that is intelligent based on the amount of memory actually
present.  Wire up the dma-direct routine for the ARM direct mapping code
as well, and otherwise default to the constant 32-bit mask.  This way
we only need to override it for the occasional odd IOMMU that requires
64-bit IOVA support, or IOMMU drivers that are more efficient if they
can fall back to the direct mapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-04 11:13:19 +02:00
Christoph Hellwig
62fcee9a3b dma-mapping: remove CONFIG_ARCH_NO_COHERENT_DMA_MMAP
CONFIG_ARCH_NO_COHERENT_DMA_MMAP is now functionally identical to
!CONFIG_MMU, so remove the separate symbol.  The only difference is that
arm did not set it for !CONFIG_MMU, but arm uses a separate dma mapping
implementation including its own mmap method, which is handled by moving
the CONFIG_MMU check in dma_can_mmap so that is only applies to the
dma-direct case, just as the other ifdefs for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	# m68k
2019-09-04 11:13:18 +02:00
Christoph Hellwig
e29ccc188f dma-mapping: add a dma_can_mmap helper
Add a helper to check if DMA allocations for a specific device can be
mapped to userspace using dma_mmap_*.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-04 11:13:18 +02:00
Christoph Hellwig
f9f3232a7d dma-mapping: explicitly wire up ->mmap and ->get_sgtable
While the default ->mmap and ->get_sgtable implementations work for the
majority of our dma_map_ops impementations they are inherently safe
for others that don't use the page allocator or CMA and/or use their
own way of remapping not covered by the common code.  So remove the
defaults if these methods are not wired up, but instead wire up the
default implementations for all safe instances.

Fixes: e1c7e32453 ("dma-mapping: always provide the dma_map_ops based implementation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-04 11:13:18 +02:00
Christoph Hellwig
1445146701 dma-mapping: move the dma_get_sgtable API comments from arm to common code
The comments are spot on and should be near the central API, not just
near a single implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-04 11:13:17 +02:00
Yoshihiro Shimoda
6ba99411b8 dma-mapping: introduce dma_get_merge_boundary()
This patch adds a new DMA API "dma_get_merge_boundary". This function
returns the DMA merge boundary if the DMA layer can merge the segments.
This patch also adds the implementation for a new dma_map_ops pointer.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-03 08:33:01 +02:00