linux.git/kernel/dma, branch v5.15-rc2

Merge tag 'dma-mapping-5.15-1' of git://git.infradead.org/users/hch/dma-mapping

2021-09-17T18:54:48+00:00

Pull dma-mapping fixes from Christoph Hellwig:

 - page align size in sparc32 arch_dma_alloc (Andreas Larsson)

 - tone down a new dma-debug message (Hamza Mahfooz)

 - fix the kerneldoc for dma_map_sg_attrs (me)

* tag 'dma-mapping-5.15-1' of git://git.infradead.org/users/hch/dma-mapping:
  sparc32: page align size in arch_dma_alloc
  dma-debug: prevent an error message from causing runtime problems
  dma-mapping: fix the kerneldoc for dma_map_sg_attrs

dma-debug: prevent an error message from causing runtime problems

2021-09-13T16:29:24+00:00

For some drivers, that use the DMA API. This error message can be reached
several millions of times per second, causing spam to the kernel's printk
buffer and bringing the CPU usage up to 100% (so, it should be rate
limited). However, since there is at least one driver that is in the
mainline and suffers from the error condition, it is more useful to
err_printk() here instead of just rate limiting the error message (in hopes
that it will make it easier for other drivers that suffer from this issue
to be spotted).

Link: https://lkml.kernel.org/r/fd67fbac-64bf-f0ea-01e1-5938ccfab9d0@arm.com
Reported-by: Jeremy Linton 
Signed-off-by: Hamza Mahfooz 
Signed-off-by: Christoph Hellwig

dma-mapping: fix the kerneldoc for dma_map_sg_attrs

2021-09-06T12:40:47+00:00

Add the missing description for the nents parameter, and fix a trivial
misalignment.

Fixes: fffe3cc8c219 ("dma-mapping: allow map_sg() ops to return negative error codes")
Reported-by: Stephen Rothwell 
Signed-off-by: Christoph Hellwig

Merge branch 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb

2021-09-03T17:34:44+00:00

Pull swiotlb updates from Konrad Rzeszutek Wilk:
 "A new feature called restricted DMA pools. It allows SWIOTLB to
  utilize per-device (or per-platform) allocated memory pools instead of
  using the global one.

  The first big user of this is ARM Confidential Computing where the
  memory for DMA operations can be set per platform"

* 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits)
  swiotlb: use depends on for DMA_RESTRICTED_POOL
  of: restricted dma: Don't fail device probe on rmem init failure
  of: Move of_dma_set_restricted_buffer() into device.c
  powerpc/svm: Don't issue ultracalls if !mem_encrypt_active()
  s390/pv: fix the forcing of the swiotlb
  swiotlb: Free tbl memory in swiotlb_exit()
  swiotlb: Emit diagnostic in swiotlb_exit()
  swiotlb: Convert io_default_tlb_mem to static allocation
  of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS
  swiotlb: add overflow checks to swiotlb_bounce
  swiotlb: fix implicit debugfs declarations
  of: Add plumbing for restricted DMA pool
  dt-bindings: of: Add restricted DMA pool
  swiotlb: Add restricted DMA pool initialization
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  ...

swiotlb: use depends on for DMA_RESTRICTED_POOL

2021-08-31T18:48:14+00:00

Use depends on instead of select for DMA_RESTRICTED_POOL; otherwise it
will make SWIOTLB user configurable and cause compile errors for some
arch (e.g. mips).

Fixes: 0b84e4f8b793 ("swiotlb: Add restricted DMA pool initialization")
Acked-by: Will Deacon 
Reported-by: Guenter Roeck 
Signed-off-by: Claire Chang 
Signed-off-by: Konrad Rzeszutek Wilk

dma-mapping: make the global coherent pool conditional

2021-08-19T07:02:39+00:00

Only build the code to support the global coherent pool if support for
it is enabled.

Signed-off-by: Christoph Hellwig 
Tested-by: Dillon Min

dma-mapping: add a dma_init_global_coherent helper

2021-08-18T14:24:11+00:00

Add a new helper to initialize the global coherent pool.  This both
cleans up the existing initialization which indirects through the
reserved_mem_ops that are normally only used for struct device, and
also allows using the global pool for non-devicetree architectures.

Signed-off-by: Christoph Hellwig 
Tested-by: Dillon Min

dma-mapping: simplify dma_init_coherent_memory

2021-08-18T14:24:10+00:00

Return the allocated dma_coherent_mem structure, set the
use_dma_pfn_offset and print the failure warning inside of
dma_init_coherent_memory instead of leaving that to the callers.

Signed-off-by: Christoph Hellwig 
Tested-by: Dillon Min

dma-mapping: allow using the global coherent pool for !ARM

2021-08-18T14:24:10+00:00

Switch an ifdef so that the global coherent pool is initialized for
any architecture that selects the DMA_GLOBAL_POOL symbol insted of
hardcoding ARM.

Signed-off-by: Christoph Hellwig 
Tested-by: Dillon Min

dma-direct: add support for dma_coherent_default_memory

2021-08-18T14:24:09+00:00

Add an option to allocate uncached memory for dma_alloc_coherent from
the global dma_coherent_default_memory.  This will allow to move
arm-nommu (and eventually other platforms) to use generic code for
allocating uncached memory from a pre-populated pool.

Note that this is a different pool from the one that platforms that
can remap at runtime use for GFP_ATOMIC allocations for now, although
there might be opportunities to eventually end up with a common codebase
for the two use cases.

Signed-off-by: Christoph Hellwig 
Tested-by: Dillon Min