swiotlb-xen has an implicit dependency on CONFIG_NEED_SG_DMA_LENGTH.
Remove it by replacing dma_length with sg_dma_len.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Convert printks to pr_<level> (excludes printk(KERN_DEBUG...)
to be more consistent throughout the xen subsystem.

Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME
Coalesce formats and add missing word spaces
Add missing newlines
Align arguments and reflow to 80 columns
Remove DRV_NAME from formats as pr_fmt adds the same content

This does change some of the prefixes of these messages
but it also does make them more consistent.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Normal boot path on system with iommu support:
swiotlb buffer will be allocated early at first and then try to initialize
iommu, if iommu for intel or AMD could setup properly, swiotlb buffer
will be freed.

The early allocating is with bootmem, and could panic when we try to use
kdump with buffer above 4G only, or with memmap to limit mem under 4G.
for example: memmap=4095M$1M to remove memory under 4G.

According to Eric, add _nopanic version and no_iotlb_memory to fail
map single later if swiotlb is still needed.

-v2: don't pass nopanic, and use -ENOMEM return value according to Eric.
     panic early instead of using swiotlb_full to panic...according to Eric/Konrad.
-v3: make swiotlb_init to be notpanic, but will affect:
     arm64, ia64, powerpc, tile, unicore32, x86.
-v4: cleanup swiotlb_init by removing swiotlb_init_with_default_size.
Suggested-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-36-git-send-email-yinghai@kernel.orgReviewed-and-tested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This change makes it so that the sync functionality also uses physical
addresses.  This helps to further reduce the use of virt_to_phys and
phys_to_virt functions.

In order to clarify things since we now have 2 physical addresses in use
inside of swiotlb_tbl_sync_single I am renaming phys to orig_addr, and
dma_addr to tlb_addr.  This way is should be clear that orig_addr is
contained within io_orig_addr and tlb_addr is an address within the
io_tlb_addr buffer.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This change makes it so that the unmap functionality also uses physical
addresses.  This helps to further reduce the use of virt_to_phys and
phys_to_virt functions.

In order to clarify things since we now have 2 physical addresses in use
inside of swiotlb_tbl_unmap_single I am renaming phys to orig_addr, and
dma_addr to tlb_addr.  This way is should be clear that orig_addr is
contained within io_orig_addr and tlb_addr is an address within the
io_tlb_addr buffer.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This change makes it so that swiotlb_tbl_map_single will return a physical
address instead of a virtual address when called.  The advantage to this once
again is that we are avoiding a number of virt_to_phys and phys_to_virt
translations by working with everything as a physical address.

One change I had to make in order to support using physical addresses is that
I could no longer trust 0 to be a invalid physical address on all platforms.
So instead I made it so that ~0 is returned on error.  This should never be a
valid return value as it implies that only one byte would be available for
use.

In order to clarify things since we now have 2 physical addresses in use
inside of swiotlb_tbl_map_single I am renaming phys to orig_addr, and
dma_addr to tlb_addr.  This way is should be clear that orig_addr is
contained within io_orig_addr and tlb_addr is an address within the
io_tlb_addr buffer.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Sparse warns us off:
drivers/xen/swiotlb-xen.c:506:1: warning: symbol 'xen_swiotlb_map_sg' was not declared. Should it be static?
drivers/xen/swiotlb-xen.c:534:1: warning: symbol 'xen_swiotlb_unmap_sg' was not declared. Should it be static?

and it looks like we do not need this function at all.
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

If everything is setup properly we would return -ENOMEM since
rc by default is set to that value. Lets not do that and return
a proper return code.

Note: The reason the early code needs this special treatment
is that it SWIOTLB library call does not return anything (and
had it failed it would call panic()) - but our function does.
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

With this patch we provide the functionality to initialize the
Xen-SWIOTLB late in the bootup cycle - specifically for
Xen PCI-frontend. We still will work if the user had
supplied 'iommu=soft' on the Linux command line.

Note: We cannot depend on after_bootmem to automatically
determine whether this is early or not. This is because
when PCI IOMMUs are initialized it is after after_bootmem but
before a lot of "other" subsystems are initialized.

CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
[v1: Fix smatch warnings]
[v2: Added check for xen_swiotlb]
[v3: Rebased with new xen-swiotlb changes]
[v4: squashed xen/swiotlb: Depending on after_bootmem is not correct in]
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

That way we can more easily reuse those errors when using the
late SWIOTLB init.
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Moving the function out of the way to prepare for the late
SWIOTLB init.
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

When running 32-bit pvops-dom0 and a driver tries to allocate a coherent
DMA-memory the xen swiotlb-implementation returned memory beyond 4GB.

The underlaying reason is that if the supplied driver passes in a
DMA_BIT_MASK(64) ( hwdev->coherent_dma_mask is set to 0xffffffffffffffff)
our dma_mask will be u64 set to 0xffffffffffffffff even if we set it to
DMA_BIT_MASK(32) previously. Meaning we do not reset the upper bits.
By using the dma_alloc_coherent_mask function - it does the proper casting
and we get 0xfffffffff.

This caused not working sound on a system with 4 GB and a 64-bit
compatible sound-card with sets the DMA-mask to 64bit.

On bare-metal and the forward-ported xen-dom0 patches from OpenSuse a coherent
DMA-memory is always allocated inside the 32-bit address-range by calling
dma_alloc_coherent_mask.

This patch adds the same functionality to xen swiotlb and is a rebase of the
original patch from Ronny Hegewald which never got upstream b/c the
underlaying reason was not understood until now.

The original email with the original patch is in:
http://old-list-archives.xen.org/archives/html/xen-devel/2010-02/msg00038.html
the original thread from where the discussion started is in:
http://old-list-archives.xen.org/archives/html/xen-devel/2010-01/msg00928.htmlSigned-off-by: NRonny Hegewald <ronny.hegewald@online.de>
Signed-off-by: NStefano Panella <stefano.panella@citrix.com>
Acked-By: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org

Sparse warns us off:
drivers/xen/swiotlb-xen.c:506:1: warning: symbol 'xen_swiotlb_map_sg' was not declared. Should it be static?
drivers/xen/swiotlb-xen.c:534:1: warning: symbol 'xen_swiotlb_unmap_sg' was not declared. Should it be static?

and it looks like we do not need this function at all.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

There is no need for those functions/variables to be visible. Make them
static and also fix the compile warnings of this sort:

drivers/xen/<some file>.c: warning: symbol '<blah>' was not declared. Should it be static?

Some of them just require including the header file that
declares the functions.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Adapt core x86 and IA64 architecture code for dma_map_ops changes: replace
alloc/free_coherent with generic alloc/free methods.
Signed-off-by: NAndrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: NKyungmin Park <kyungmin.park@samsung.com>
[removed swiotlb related changes and replaced it with wrappers,
 merged with IA64 patch to avoid inter-patch dependences in intel-iommu code]
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NTony Luck <tony.luck@intel.com>

This fixes an odd bug found on a Dell PowerEdge 1850/0RC130
(BIOS A05 01/09/2006) where all of the modules doing pci_set_dma_mask
would fail with:

ata_piix 0000:00:1f.1: enabling device (0005 -> 0007)
ata_piix 0000:00:1f.1: can't derive routing for PCI INT A
ata_piix 0000:00:1f.1: BMDMA: failed to set dma mask, falling back to PIO

The issue was the Xen-SWIOTLB was allocated such as that the end of
buffer was stradling a page (and also above 4GB). The fix was
spotted by Kalev Leonid  which was to piggyback on git commit
e79f86b2 "swiotlb: Use page alignment
for early buffer allocation" which:

	We could call free_bootmem_late() if swiotlb is not used, and
	it will shrink to page alignment.

	So alloc them with page alignment at first, to avoid lose two pages

And doing that fixes the outstanding issue.

CC: stable@kernel.org
Suggested-by: N"Kalev, Leonid" <Leonid.Kalev@ca.com>
Reported-and-Tested-by: N"Taylor, Neal E" <Neal.Taylor@ca.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

As a mechanism to detect whether SWIOTLB is enabled or not.
We also fix the spelling - it was swioltb instead of
swiotlb.

CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
[v1: Ripped out swiotlb_enabled]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Things like THIS_MODULE and EXPORT_SYMBOL were simply everywhere
because module.h was also everywhere.  But we are fixing the latter.
So we need to call out the real users in advance.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The process to swizzle a Machine Frame Number (MFN) is not always
necessary. Especially if we know that we actually do not have to do it.
In this patch we check the MFN against the device's coherent
DMA mask and if the requested page(s) are contingous. If it all checks
out we will just return the bus addr without doing the memory
swizzle.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Fix printk() and panic() args [swap them] to fix build warnings:

drivers/xen/swiotlb-xen.c:201: warning: format '%s' expects type 'char *', but argument 2 has type 'int'
drivers/xen/swiotlb-xen.c:201: warning: format '%d' expects type 'int', but argument 3 has type 'char *'
drivers/xen/swiotlb-xen.c:202: warning: format '%s' expects type 'char *', but argument 2 has type 'int'
drivers/xen/swiotlb-xen.c:202: warning: format '%d' expects type 'int', but argument 3 has type 'char *'
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Propagate the baremetal git commit "swiotlb: fix wrong panic"
(fba99fa3) in the Xen-SWIOTLB version.
wherein swiotlb's map_page wrongly calls panic() when it can't find
a buffer fit for device's dma mask.  It should return an error instead.

Devices with an odd dma mask (i.e.  under 4G) like b44 network card hit
this bug (the system crashes):

http://marc.info/?l=linux-kernel&m=129648943830106&w=2

If xen-swiotlb returns an error, b44 driver can use the own bouncing
mechanism.

CC: stable@kernel.org
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We can fail seting up Xen-SWIOTLB if:
 - The host does not have enough contiguous DMA32 memory available
   (can happen on a machine that has fragmented memory from starting,
   stopping many guests).
 - Not enough low memory (almost never happens).

We retry allocating and exchanging the swath of contiguous memory
up to three times. Each time we decrease the amount we need  - the
minimum being of 2MB.

If we compleltly fail, we will print the reason for failure on the Xen
console on top of doing it to earlyprintk=xen console.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

By default the io_tlb_nslabs is set to zero, and gets set to
whatever value is passed in via swiotlb_init_with_tbl function.
The default value passed in is 64MB. However, if the user provides
the 'swiotlb=<nslabs>' the default value is ignored and
the value provided by the user is used... Except when the SWIOTLB
is used under Xen - there the default value of 64MB is used and
the Xen-SWIOTLB has no mechanism to get the 'io_tlb_nslabs' filled
out by setup_io_tlb_npages functions. This patch provides a function
for the Xen-SWIOTLB to call to see if the io_tlb_nslabs is set
and if so use that value.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Signed-off-by: NJustin P. Mattock <justinmattock@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This patchset:

PV guests under Xen are running in an non-contiguous memory architecture.

When PCI pass-through is utilized, this necessitates an IOMMU for
translating bus (DMA) to virtual and vice-versa and also providing a
mechanism to have contiguous pages for device drivers operations (say DMA
operations).

Specifically, under Xen the Linux idea of pages is an illusion. It
assumes that pages start at zero and go up to the available memory. To
help with that, the Linux Xen MMU provides a lookup mechanism to
translate the page frame numbers (PFN) to machine frame numbers (MFN)
and vice-versa. The MFN are the "real" frame numbers. Furthermore
memory is not contiguous. Xen hypervisor stitches memory for guests
from different pools, which means there is no guarantee that PFN==MFN
and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are
allocated in descending order (high to low), meaning the guest might
never get any MFN's under the 4GB mark.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Albert Herranz <albert_herranz@yahoo.es>
Cc: Ian Campbell <Ian.Campbell@citrix.com>