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    dma-mapping: add the device argument to dma_mapping_error() · 8d8bb39b
    FUJITA Tomonori authored
    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: default avatarFUJITA 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: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    8d8bb39b