linux-toradex.git/include/linux/dma-mapping.h, branch v4.6-rc3

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2016-03-20T20:28:18+00:00

Pull virtio/vhost updates from Michael Tsirkin:
 "New features, performance improvements, cleanups:

   - basic polling support for vhost
   - rework virtio to optionally use DMA API, fixing it on Xen
   - balloon stats gained a new entry
   - using the new napi_alloc_skb speeds up virtio net
   - virtio blk stats can now be read while another VCPU is busy
     inflating or deflating the balloon

  plus misc cleanups in various places"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_net: replace netdev_alloc_skb_ip_align() with napi_alloc_skb()
  vhost_net: basic polling support
  vhost: introduce vhost_vq_avail_empty()
  vhost: introduce vhost_has_work()
  virtio_balloon: Allow to resize and update the balloon stats in parallel
  virtio_balloon: Use a workqueue instead of "vballoon" kthread
  virtio/s390: size of SET_IND payload
  virtio/s390: use dev_to_virtio
  vhost: rename vhost_init_used()
  vhost: rename cross-endian helpers
  virtio_blk: VIRTIO_BLK_F_WCE->VIRTIO_BLK_F_FLUSH
  vring: Use the DMA API on Xen
  virtio_pci: Use the DMA API if enabled
  virtio_mmio: Use the DMA API if enabled
  virtio: Add improved queue allocation API
  virtio_ring: Support DMA APIs
  vring: Introduce vring_use_dma_api()
  s390/dma: Allow per device dma ops
  alpha/dma: use common noop dma ops
  dma: Provide simple noop dma ops

Merge branch 'mm-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-03-14T23:31:41+00:00

Pull dma_*_writecombine rename from Ingo Molnar:
 "Rename dma_*_writecombine() to dma_*_wc()

  This is a tree-wide API rename, to move the dma_*() write-combining
  APIs closer in name to their usual API families.  (The old API names
  are kept as compatibility wrappers to not introduce extra breakage.)

  The patch was Coccinelle generated"

* 'mm-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  dma, mm/pat: Rename dma_*_writecombine() to dma_*_wc()

dma-mapping: avoid oops when parameter cpu_addr is null

2016-03-09T23:43:42+00:00

To keep consistent with kfree, which tolerate ptr is NULL.  We do this
because sometimes we may use goto statement, so that success and failure
case can share parts of the code.  But unfortunately, dma_free_coherent
called with parameter cpu_addr is null will cause oops, such as showed
below:

  Unable to handle kernel paging request at virtual address ffffffc020d3b2b8
  pgd = ffffffc083a61000
  [ffffffc020d3b2b8] *pgd=0000000000000000, *pud=0000000000000000
  CPU: 4 PID: 1489 Comm: malloc_dma_1 Tainted: G           O    4.1.12 #1
  Hardware name: ARM64 (DT)
  PC is at __dma_free_coherent.isra.10+0x74/0xc8
  LR is at __dma_free+0x9c/0xb0
  Process malloc_dma_1 (pid: 1489, stack limit = 0xffffffc0837fc020)
  [...]
  Call trace:
    __dma_free_coherent.isra.10+0x74/0xc8
    __dma_free+0x9c/0xb0
    malloc_dma+0x104/0x158 [dma_alloc_coherent_mtmalloc]
    kthread+0xec/0xfc

Signed-off-by: Zhen Lei 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma, mm/pat: Rename dma__writecombine() to dma__wc()

2016-03-09T13:57:51+00:00

Rename dma_*_writecombine() to dma_*_wc(), so that the naming
is coherent across the various write-combining APIs. Keep the
old names for compatibility for a while, these can be removed
at a later time. A guard is left to enable backporting of the
rename, and later remove of the old mapping defines seemlessly.

Build tested successfully with allmodconfig.

The following Coccinelle SmPL patch was used for this simple
transformation:

@ rename_dma_alloc_writecombine @
expression dev, size, dma_addr, gfp;
@@

-dma_alloc_writecombine(dev, size, dma_addr, gfp)
+dma_alloc_wc(dev, size, dma_addr, gfp)

@ rename_dma_free_writecombine @
expression dev, size, cpu_addr, dma_addr;
@@

-dma_free_writecombine(dev, size, cpu_addr, dma_addr)
+dma_free_wc(dev, size, cpu_addr, dma_addr)

@ rename_dma_mmap_writecombine @
expression dev, vma, cpu_addr, dma_addr, size;
@@

-dma_mmap_writecombine(dev, vma, cpu_addr, dma_addr, size)
+dma_mmap_wc(dev, vma, cpu_addr, dma_addr, size)

We also keep the old names as compatibility helpers, and
guard against their definition to make backporting easier.

Generated-by: Coccinelle SmPL
Suggested-by: Ingo Molnar 
Signed-off-by: Luis R. Rodriguez 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bhelgaas@google.com
Cc: bp@suse.de
Cc: dan.j.williams@intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dhowells@redhat.com
Cc: julia.lawall@lip6.fr
Cc: konrad.wilk@oracle.com
Cc: linux-fbdev@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: luto@amacapital.net
Cc: mst@redhat.com
Cc: tomi.valkeinen@ti.com
Cc: toshi.kani@hp.com
Cc: vinod.koul@intel.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1453516462-4844-1-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar

dma: Provide simple noop dma ops

2016-03-02T15:01:55+00:00

We are going to require dma_ops for several common drivers, even for
systems that do have an identity mapping. Lets provide some minimal
no-op dma_ops that can be used for that purpose.

Signed-off-by: Christian Borntraeger 
Reviewed-by: Joerg Roedel 
Signed-off-by: Andy Lutomirski 
Signed-off-by: Michael S. Tsirkin

dma-mapping: use offset_in_page macro

2016-01-21T01:09:18+00:00

Use offset_in_page macro instead of (addr & ~PAGE_MASK).

Signed-off-by: Geliang Tang 
Acked-by: Will Deacon 
Cc: Christian Borntraeger 
Cc: Joerg Roedel 
Cc: Sebastian Ott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: remove

2016-01-21T01:09:18+00:00

This wasn't an asm-generic header to start with, and can be merged into
dma-mapping.h trivially.

Signed-off-by: Christoph Hellwig 
Cc: "David S. Miller" 
Cc: Aurelien Jacquiot 
Cc: Chris Metcalf 
Cc: David Howells 
Cc: Geert Uytterhoeven 
Cc: Haavard Skinnemoen 
Cc: Hans-Christian Egtvedt 
Cc: Helge Deller 
Cc: James Hogan 
Cc: Jesper Nilsson 
Cc: Koichi Yasutake 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Mikael Starvik 
Cc: Steven Miao 
Cc: Vineet Gupta 
Cc: Christian Borntraeger 
Cc: Joerg Roedel 
Cc: Sebastian Ott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: always provide the dma_map_ops based implementation

2016-01-21T01:09:18+00:00

Move the generic implementation to  now that all
architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now
that everyone supports them.

[valentinrothberg@gmail.com: remove leftovers in Kconfig]
Signed-off-by: Christoph Hellwig 
Cc: "David S. Miller" 
Cc: Aurelien Jacquiot 
Cc: Chris Metcalf 
Cc: David Howells 
Cc: Geert Uytterhoeven 
Cc: Haavard Skinnemoen 
Cc: Hans-Christian Egtvedt 
Cc: Helge Deller 
Cc: James Hogan 
Cc: Jesper Nilsson 
Cc: Koichi Yasutake 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Mikael Starvik 
Cc: Steven Miao 
Cc: Vineet Gupta 
Cc: Christian Borntraeger 
Cc: Joerg Roedel 
Cc: Sebastian Ott 
Signed-off-by: Valentin Rothberg 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: tidy up dma_parms default handling

2015-11-07T01:50:42+00:00

Many DMA controllers and other devices set max_segment_size to
indicate their scatter-gather capability, but have no interest in
segment_boundary_mask. However, the existence of a dma_parms structure
precludes the use of any default value, leaving them as zeros (assuming
a properly kzalloc'ed structure). If a well-behaved IOMMU (or SWIOTLB)
then tries to respect this by ensuring a mapped segment does not cross
a zero-byte boundary, hilarity ensues.

Since zero is a nonsensical value for either parameter, treat it as an
indicator for "default", as might be expected. In the process, clean up
a bit by replacing the bare constants with slightly more meaningful
macros and removing the superfluous "else" statements.

[akpm@linux-foundation.org: dma-mapping.h needs sizes.h for SZ_64K]
Signed-off-by: Robin Murphy 
Reviewed-by: Sumit Semwal 
Acked-by: Marek Szyprowski 
Cc: Arnd Bergmann 
Cc: Sakari Ailus 
Cc: Russell King 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

include/dma-mapping: Clarify output of dma_map_sg

2015-03-09T12:05:47+00:00

Although dma_map_sg returns 0 on error and it cannot return a
value < 0, the function returns a signed integer.

Most of the time, this function is used with a scatterlist structure.
This structure uses an unsigned integer for the number of memory.

A dma developer that has not read in detail DMA-API.txt, can wrongly
return a value < 0 on error.

Signed-off-by: Ricardo Ribalda Delgado 
Signed-off-by: Marek Szyprowski