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  1. 27 11月, 2013 1 次提交
  3. 15 11月, 2013 2 次提交
  5. 09 11月, 2013 3 次提交
  7. 07 11月, 2013 1 次提交
  9. 29 10月, 2013 1 次提交
  11. 25 10月, 2013 4 次提交
  13. 24 10月, 2013 1 次提交
  15. 17 10月, 2013 1 次提交
  17. 10 10月, 2013 4 次提交
    • S
      swiotlb-xen: use xen_alloc/free_coherent_pages · 1b65c4e5
      由 Stefano Stabellini 提交于 
      Use xen_alloc_coherent_pages and xen_free_coherent_pages to allocate or
free coherent pages.

We need to be careful handling the pointer returned by
xen_alloc_coherent_pages, because on ARM the pointer is not equal to
phys_to_virt(*dma_handle). In fact virt_to_phys only works for kernel
direct mapped RAM memory.
In ARM case the pointer could be an ioremap address, therefore passing
it to virt_to_phys would give you another physical address that doesn't
correspond to it.

Make xen_create_contiguous_region take a phys_addr_t as start parameter to
avoid the virt_to_phys calls which would be incorrect.

Changes in v6:
- remove extra spaces.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      1b65c4e5
    • S
      swiotlb-xen: introduce xen_swiotlb_set_dma_mask · eb1ddc00
      由 Stefano Stabellini 提交于 
      Implement xen_swiotlb_set_dma_mask, use it for set_dma_mask on arm.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
      eb1ddc00
    • S
      xen/arm,arm64: enable SWIOTLB_XEN · 83862ccf
      由 Stefano Stabellini 提交于 
      Xen on arm and arm64 needs SWIOTLB_XEN: when running on Xen we need to
program the hardware with mfns rather than pfns for dma addresses.
Remove SWIOTLB_XEN dependency on X86 and PCI and make XEN select
SWIOTLB_XEN on arm and arm64.

At the moment always rely on swiotlb-xen, but when Xen starts supporting
hardware IOMMUs we'll be able to avoid it conditionally on the presence
of an IOMMU on the platform.

Implement xen_create_contiguous_region on arm and arm64: for the moment
we assume that dom0 has been mapped 1:1 (physical addresses == machine
addresses) therefore we don't need to call XENMEM_exchange. Simply
return the physical address as dma address.

Initialize the xen-swiotlb from xen_early_init (before the native
dma_ops are initialized), set xen_dma_ops to &xen_swiotlb_dma_ops.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>


Changes in v8:
- assume dom0 is mapped 1:1, no need to call XENMEM_exchange.

Changes in v7:
- call __set_phys_to_machine_multi from xen_create_contiguous_region and
xen_destroy_contiguous_region to update the P2M;
- don't call XENMEM_unpin, it has been removed;
- call XENMEM_exchange instead of XENMEM_exchange_and_pin;
- set nr_exchanged to 0 before calling the hypercall.

Changes in v6:
- introduce and export xen_dma_ops;
- call xen_mm_init from as arch_initcall.

Changes in v4:
- remove redefinition of DMA_ERROR_CODE;
- update the code to use XENMEM_exchange_and_pin and XENMEM_unpin;
- add a note about hardware IOMMU in the commit message.

Changes in v3:
- code style changes;
- warn on XENMEM_put_dma_buf failures.
      83862ccf
    • S
      xen: make xen_create_contiguous_region return the dma address · 69908907
      由 Stefano Stabellini 提交于 
      Modify xen_create_contiguous_region to return the dma address of the
newly contiguous buffer.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>


Changes in v4:
- use virt_to_machine instead of virt_to_bus.
      69908907
  19. 03 10月, 2013 1 次提交
    • Z
      tracing/events: Add bounce tracing to swiotbl · 2b2b614d
      由 Zoltan Kiss 提交于 
      Ftrace is currently not able to detect when SWIOTLB has to do double buffering.
Under Xen you can only see it indirectly in function_graph, when
xen_swiotlb_map_page() doesn't stop after range_straddles_page_boundary(), but
calls spinlock functions, memcpy() and xen_phys_to_bus() as well. This patch
introduces the swiotlb:swiotlb_bounced event, which also prints out the
following informations to help you find out why bouncing happened:

dev_name: 0000:08:00.0 dma_mask=ffffffffffffffff dev_addr=9149f000 size=32768
swiotlb_force=0

If you use Xen, and (dev_addr + size + 1) > dma_mask, the buffer is out of the
device's DMA range. If swiotlb_force == 1, you should really change the kernel
parameters. Otherwise, the buffer is not contiguous in mfn space.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
[v1: Don't print 'swiotlb_force=X', just print swiotlb_force if it is enabled]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      2b2b614d
  21. 25 9月, 2013 1 次提交
  23. 12 9月, 2013 2 次提交
  25. 31 8月, 2013 1 次提交
  27. 30 8月, 2013 2 次提交
  29. 20 8月, 2013 5 次提交
  31. 09 8月, 2013 6 次提交
  33. 31 7月, 2013 2 次提交
  35. 30 7月, 2013 1 次提交
    • D
      xen/evtchn: avoid a deadlock when unbinding an event channel · 179fbd5a
      由 David Vrabel 提交于 
      Unbinding an event channel (either with the ioctl or when the evtchn
device is closed) may deadlock because disable_irq() is called with
port_user_lock held which is also locked by the interrupt handler.

Think of the IOCTL_EVTCHN_UNBIND is being serviced, the routine has
just taken the lock, and an interrupt happens. The evtchn_interrupt
is invoked, tries to take the lock and spins forever.

A quick glance at the code shows that the spinlock is a local IRQ
variant. Unfortunately that does not help as "disable_irq() waits for
the interrupt handler on all CPUs to stop running.  If the irq occurs
on another VCPU, it tries to take port_user_lock and can't because
the unbind ioctl is holding it." (from David). Hence we cannot
depend on the said spinlock to protect us. We could make it a system
wide IRQ disable spinlock but there is a better way.

We can piggyback on the fact that the existence of the spinlock is
to make get_port_user() checks be up-to-date. And we can alter those
checks to not depend on the spin lock (as it's protected by u->bind_mutex
in the ioctl) and can remove the unnecessary locking (this is
IOCTL_EVTCHN_UNBIND) path.

In the interrupt handler we cannot use the mutex, but we do not
need it.

"The unbind disables the irq before making the port user stale, so when
you clear it you are guaranteed that the interrupt handler that might
use that port cannot be running." (from David).

Hence this patch removes the spinlock usage on the teardown path
and piggybacks on disable_irq happening before we muck with the
get_port_user() data. This ensures that the interrupt handler will
never run on stale data.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v1: Expanded the commit description a bit]
      179fbd5a
  37. 29 7月, 2013 1 次提交