1. 27 7月, 2008 1 次提交
    • F
      dma-mapping: add the device argument to dma_mapping_error() · 8d8bb39b
      FUJITA Tomonori 提交于
      Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
      architecture does:
      
      This enables us to cleanly fix the Calgary IOMMU issue that some devices
      are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423).
      
      I think that per-device dma_mapping_ops support would be also helpful for
      KVM people to support PCI passthrough but Andi thinks that this makes it
      difficult to support the PCI passthrough (see the above thread).  So I
      CC'ed this to KVM camp.  Comments are appreciated.
      
      A pointer to dma_mapping_ops to struct dev_archdata is added.  If the
      pointer is non NULL, DMA operations in asm/dma-mapping.h use it.  If it's
      NULL, the system-wide dma_ops pointer is used as before.
      
      If it's useful for KVM people, I plan to implement a mechanism to register
      a hook called when a new pci (or dma capable) device is created (it works
      with hot plugging).  It enables IOMMUs to set up an appropriate
      dma_mapping_ops per device.
      
      The major obstacle is that dma_mapping_error doesn't take a pointer to the
      device unlike other DMA operations.  So x86 can't have dma_mapping_ops per
      device.  Note all the POWER IOMMUs use the same dma_mapping_error function
      so this is not a problem for POWER but x86 IOMMUs use different
      dma_mapping_error functions.
      
      The first patch adds the device argument to dma_mapping_error.  The patch
      is trivial but large since it touches lots of drivers and dma-mapping.h in
      all the architecture.
      
      This patch:
      
      dma_mapping_error() doesn't take a pointer to the device unlike other DMA
      operations.  So we can't have dma_mapping_ops per device.
      
      Note that POWER already has dma_mapping_ops per device but all the POWER
      IOMMUs use the same dma_mapping_error function.  x86 IOMMUs use device
      argument.
      
      [akpm@linux-foundation.org: fix sge]
      [akpm@linux-foundation.org: fix svc_rdma]
      [akpm@linux-foundation.org: build fix]
      [akpm@linux-foundation.org: fix bnx2x]
      [akpm@linux-foundation.org: fix s2io]
      [akpm@linux-foundation.org: fix pasemi_mac]
      [akpm@linux-foundation.org: fix sdhci]
      [akpm@linux-foundation.org: build fix]
      [akpm@linux-foundation.org: fix sparc]
      [akpm@linux-foundation.org: fix ibmvscsi]
      Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
      Cc: Muli Ben-Yehuda <muli@il.ibm.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Avi Kivity <avi@qumranet.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8d8bb39b
  2. 22 7月, 2008 1 次提交
  3. 19 7月, 2008 1 次提交
  4. 11 7月, 2008 4 次提交
  5. 08 7月, 2008 1 次提交
  6. 27 6月, 2008 1 次提交
  7. 10 6月, 2008 1 次提交
    • M
      x86, pci-dma.c: don't always add __GFP_NORETRY to gfp · b7f09ae5
      Miquel van Smoorenburg 提交于
      Currently arch/x86/kernel/pci-dma.c always adds __GFP_NORETRY
      to the allocation flags, because it wants to be reasonably
      sure not to deadlock when calling alloc_pages().
      
      But really that should only be done in two cases:
      - when allocating memory in the lower 16 MB DMA zone.
        If there's no free memory there, waiting or OOM killing is of no use
      - when optimistically trying an allocation in the DMA32 zone
        when dma_mask < DMA_32BIT_MASK hoping that the allocation
        happens to fall within the limits of the dma_mask
      
      Also blindly adding __GFP_NORETRY to the the gfp variable might
      not be a good idea since we then also use it when calling
      dma_ops->alloc_coherent(). Clearing it might also not be a
      good idea, dma_alloc_coherent()'s caller might have set it
      on purpose. The gfp variable should not be clobbered.
      
      [ mingo@elte.hu: converted to delta patch ontop of previous version. ]
      Signed-off-by: NMiquel van Smoorenburg <miquels@cistron.nl>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      b7f09ae5
  8. 02 6月, 2008 1 次提交
    • M
      x86: pci-dma.c: use __GFP_NO_OOM instead of __GFP_NORETRY · db9f600b
      Miquel van Smoorenburg 提交于
      On Wed, 2008-05-28 at 04:47 +0200, Andi Kleen wrote:
      > > So...  why not just remove the setting of __GFP_NORETRY?  Why is it
      > > wrong to oom-kill things in this case?
      >
      > When the 16MB zone overflows (which can be common in some workloads)
      > calling the OOM killer is pretty useless because it has barely any
      > real user data [only exception would be the "only 16MB" case Alan
      > mentioned]. Killing random processes in this case is bad.
      >
      > I think for 16MB __GFP_NORETRY is ok because there should be
      > nothing freeable in there so looping is useless. Only exception would be the
      > "only 16MB total" case again but I'm not sure 2.6 supports that at all
      > on x86.
      >
      > On the other hand d_a_c() does more allocations than just 16MB, especially
      > on 64bit and the other zones need different strategies.
      
      Okay, so how about this then ?
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      db9f600b
  9. 25 5月, 2008 1 次提交
  10. 14 5月, 2008 1 次提交
  11. 13 5月, 2008 3 次提交
  12. 01 5月, 2008 1 次提交
  13. 20 4月, 2008 11 次提交