Impact: reduce kernel size a bit, address sparse warning

Addresses the problem pointed out by this sparse warning:

  arch/x86/kernel/pci-swiotlb.c:53:20: warning: symbol 'swiotlb_dma_ops' was not declared. Should it be static?

For x86: swiotlb_dma_ops can be static, because it's not used outside
of pci-swiotlb.c
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
LKML-Reference: <1239558861.3938.2.camel@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The file is used for 32 and 64 bit since:

  commit cfb80c9e
  Author: Jeremy Fitzhardinge <jeremy@goop.org>
  Date:   Tue Dec 16 12:17:36 2008 -0800

    x86: unify pci iommu setup and allow swiotlb to compile for 32 bit
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The swiotlb_arch_range_needs_mapping() hook should take a physical
address rather than a virtual address in order to support highmem pages.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This adds swiotlb_map_page and swiotlb_unmap_page to lib/swiotlb.c and
remove IA64 and X86's swiotlb_map_page and swiotlb_unmap_page.

This also removes unnecessary swiotlb_map_single, swiotlb_map_single_attrs,
swiotlb_unmap_single and swiotlb_unmap_single_attrs.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This converts X86 and IA64 to use include/linux/dma-mapping.h.

It's a bit large but pretty boring. The major change for X86 is
converting 'int dir' to 'enum dma_data_direction dir' in DMA mapping
operations. The major changes for IA64 is using map_page and
unmap_page instead of map_single and unmap_single.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch converts dma_map_single and dma_unmap_single to use
map_page and unmap_page respectively and removes unnecessary
map_single and unmap_single in struct dma_mapping_ops.

This leaves intel-iommu's dma_map_single and dma_unmap_single since
IA64 uses them. They will be removed after the unification.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This is a preparation of struct dma_mapping_ops unification. We use
map_page and unmap_page instead of map_single and unmap_single.

This is sorta temporary workaround. We will move them to lib/swiotlb.c
to enable x86's swiotlb code to directly use them.

We will remove map_single and unmap_single hooks in the last patch in
this patchset.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup, reduce kernel size a bit

The current kernel build warns:

    WARNING: vmlinux.o(.text+0x11458): Section mismatch in reference from the function swiotlb_alloc_boot() to the function .init.text:__alloc_bootmem_low()
    The function swiotlb_alloc_boot() references
    the function __init __alloc_bootmem_low().
    This is often because swiotlb_alloc_boot lacks a __init
    annotation or the annotation of __alloc_bootmem_low is wrong.

    WARNING: vmlinux.o(.text+0x1011f2): Section mismatch in reference from the function swiotlb_late_init_with_default_size() to the function .init.text:__alloc_bootmem_low()
    The function swiotlb_late_init_with_default_size() references
    the function __init __alloc_bootmem_low().
    This is often because swiotlb_late_init_with_default_size lacks a __init
    annotation or the annotation of __alloc_bootmem_low is wrong.

and indeed the functions calling __alloc_bootmem_low() can be marked
__init as well.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: extend functions with a (yet unused) parameter, update callsites

Some architectures need it - in preparation for highmem swiotlb.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Xen will override these later on.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Xen will override these later on.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

swiotlb on 32 bit will be used by Xen domain 0 support.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add x86-specific swiotlb allocation functions.  These are purely
default for the moment.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This restores the old swiotlb alloc_coherent behavior (before the
alloc_coherent rewrite):

  http://lkml.org/lkml/2008/8/12/200

The old alloc_coherent avoids GFP_DMA allocation first and if the
allocated address is not fit for the device's coherent_dma_mask, then
dma_alloc_coherent does GFP_DMA allocation. If it fails,
alloc_coherent calls swiotlb_alloc_coherent (in short, we rarely used
swiotlb_alloc_coherent).

After the alloc_coherent rewrite, dma_alloc_coherent
(include/asm-x86/dma-mapping.h) directly calls swiotlb_alloc_coherent.
It means that we possibly can't handle a device having dma_masks >
24bit < 32bits since swiotlb_alloc_coherent doesn't have the above
GFP_DMA retry mechanism.

This patch fixes x86's swiotlb alloc_coherent to use the GFP_DMA retry
mechanism, which dma_generic_alloc_coherent() provides now
(pci-nommu.c and GART IOMMU driver also use
dma_generic_alloc_coherent).
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

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>

gart.h has only GART-specific stuff. Only GART code needs it. Other
IOMMU stuff should include iommu.h instead of gart.h.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

and use max_pfn directly.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch renames the include file asm-x86/iommu.h to asm-x86/gart.h to make
clear to which IOMMU implementation it belongs. The patch also adds "GART" to
the Kconfig line.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Acked-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

[akpm@linux-foundation.org: build fix]
Signed-off-by: NYinghai Lu <yinghai.lu@sun.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The dma_ops structure can be const since it never changes
after boot.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NAndi Kleen <ak@suse.de>

- add proper __init decoration to swiotlb's init code (and the code calling
  it, where not already the case)

- replace uses of 'unsigned long' with dma_addr_t where appropriate

- do miscellaneous simplicfication and cleanup
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NTony Luck <tony.luck@intel.com>

As suggested by Muli Ben-Yehuda this function is moved to generic code as
may be useful for all archs.

[akpm@osdl.org: fix]
Signed-off-by: NRolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It was broken before. But having it is important as possible hardware
bug workaround.

And previously there was no way to force swiotlb if there is another IOMMU.
Side effect is that iommu=force won't force swiotlb anymore even if there
isn't another IOMMU.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

swiotlb relies on the gart specific iommu_aperture variable to know if
we discovered a hardware IOMMU before swiotlb initialization.  Introduce
iommu_detected to do the same thing, but in a HW IOMMU neutral manner,
in preparation for adding the Calgary HW IOMMU.
Signed-Off-By: NMuli Ben-Yehuda <muli@il.ibm.com>
Signed-Off-By: NJon Mason <jdmason@us.ibm.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains a printk reorder to remove the current problem of
displaying "PCI-DMA: Disabling IOMMU." and then "PCI-DMA: using GART
IOMMU" 20 lines later in dmesg.

It also constains a printk reorder in swiotlb to state swiotlb
enablement prior to describing the location of the bounce buffers, and a
printk reorder to state gart enablement prior to describing the
aperature.

Also constains a whitespace cleanup in arch/x86_64/kernel/setup.c

Tested (along with patch 2/2) on dual opteron with gart enabled,
iommu=soft, and iommu=off.
Signed-off-by: NJon Mason <jdmason@us.ibm.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

AK: I hacked Muli's original patch a lot and there were a lot
of changes - all bugs are probably to blame on me now.
There were also some changes in the fall back behaviour
for swiotlb - in particular it doesn't try to use GFP_DMA
now anymore. Also all DMA mapping operations use the
same core dma_alloc_coherent code with proper fallbacks now.
And various other changes and cleanups.

Known problems: iommu=force swiotlb=force together breaks
                needs more testing.

This patch cleans up x86_64's DMA mapping dispatching code. Right now
we have three possible IOMMU types: AGP GART, swiotlb and nommu, and
in the future we will also have Xen's x86_64 swiotlb and other HW
IOMMUs for x86_64. In order to support all of them cleanly, this
patch:

- introduces a struct dma_mapping_ops with function pointers for each
  of the DMA mapping operations of gart (AMD HW IOMMU), swiotlb
  (software IOMMU) and nommu (no IOMMU).

- gets rid of:

  if (swiotlb)
      return swiotlb_xxx();

- PCI_DMA_BUS_IS_PHYS is now checked against the dma_ops being set
This makes swiotlb faster by avoiding double copying in some cases.
Signed-Off-By: NMuli Ben-Yehuda <mulix@mulix.org>
Signed-Off-By: NJon D. Mason <jdmason@us.ibm.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>