Chao said that kdump does does work well on his system on 3.8
without extra parameter, even iommu does not work with kdump.
And now have to append crashkernel_low=Y in first kernel to make
kdump work.
We have now modified crashkernel=X to allocate memory beyong 4G (if
available) and do not allocate low range for crashkernel if the user
does not specify that with crashkernel_low=Y. This causes regression
if iommu is not enabled. Without iommu, swiotlb needs to be setup in
first 4G and there is no low memory available to second kernel.
Set crashkernel_low automatically if the user does not specify that.
For system that does support IOMMU with kdump properly, user could
specify crashkernel_low=0 to save that 72M low ram.
-v3: add swiotlb_size() according to Konrad.
-v4: add comments what 8M is for according to hpa.
also update more crashkernel_low= in kernel-parameters.txt
-v5: update changelog according to Vivek.
-v6: Change description about swiotlb referring according to HATAYAMA.
Reported-by: WANG Chao <chaowang@redhat.com>
Tested-by: WANG Chao <chaowang@redhat.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1366089828-19692-2-git-send-email-yinghai@kernel.org
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Currently swiotlb is the only consumer for swiotlb_bounce. Since that is the
case it doesn't make much sense to be exporting it so make it a static
function only.
In addition we can save a few more lines of code by making it so that it
accepts the DMA address as a physical address instead of a virtual one. This
is the last piece in essentially pushing all of the DMA address values to use
physical addresses in swiotlb.
In order to clarify things since we now have 2 physical addresses in use
inside of swiotlb_bounce 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: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.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: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad 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: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad 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: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This change makes it so that we can avoid virt_to_phys overhead when using the
io_tlb_overflow_buffer. My original plan was to completely remove the value
and replace it with a constant but I had seen that there were recent patches
that stated this couldn't be done until all device drivers that depended on
that functionality be updated.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This change replaces all references to the virtual address for io_tlb_start
with references to the physical address io_tlb_end. The main advantage of
replacing the virtual address with a physical address is that we can avoid
having to do multiple translations from the virtual address to the physical
one needed for testing an existing DMA address.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This change replaces all references to the virtual address for io_tlb_end
with references to the physical address io_tlb_end. The main advantage of
replacing the virtual address with a physical address is that we can avoid
having to do multiple translations from the virtual address to the physical
one needed for testing an existing DMA address.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This enables the caller to initialize swiotlb with its own iotlb
memory late in the bootup.
See git commit eb605a5754
"swiotlb: add swiotlb_tbl_map_single library function" which will
explain the full details of what it can be used for.
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
[v1: Fold in smatch warning]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Print swiotlb info in a style consistent with the %pR style used elsewhere
in the kernel. For example:
-Placing 64MB software IO TLB between ffff88007a662000 - ffff88007e662000
-software IO TLB at phys 0x7a662000 - 0x7e662000
+software IO TLB [mem 0x7a662000-0x7e661fff] (64MB) mapped at [ffff88007a662000-ffff88007e661fff]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker:
"Fix up files in fs/ and lib/ dirs to only use module.h if they really
need it.
These are trivial in scope vs the work done previously. We now have
things where any few remaining cleanups can be farmed out to arch or
subsystem maintainers, and I have done so when possible. What is
remaining here represents the bits that don't clearly lie within a
single arch/subsystem boundary, like the fs dir and the lib dir.
Some duplicate includes arising from overlapping fixes from
independent subsystem maintainer submissions are also quashed."
Fix up trivial conflicts due to clashes with other include file cleanups
(including some due to the previous bug.h cleanup pull).
* tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
lib: reduce the use of module.h wherever possible
fs: reduce the use of module.h wherever possible
includecheck: delete any duplicate instances of module.h
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include. Fix up any implicit
include dependencies that were being masked by module.h along
the way.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.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: Konrad 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: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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
before patch:
[ 0.000000] memblock_x86_reserve_range: [00d3600000, 00d7600000] swiotlb buffer
[ 0.000000] memblock_x86_reserve_range: [00d7e7ef40, 00d7e9ef40] swiotlb list
[ 0.000000] memblock_x86_reserve_range: [00d7e3ef40, 00d7e7ef40] swiotlb orig_ad
[ 0.000000] memblock_x86_reserve_range: [000008a000, 0000092000] swiotlb overflo
after patch will get
[ 0.000000] memblock_x86_reserve_range: [00d3600000, 00d7600000] swiotlb buffer
[ 0.000000] memblock_x86_reserve_range: [00d7e7e000, 00d7e9e000] swiotlb list
[ 0.000000] memblock_x86_reserve_range: [00d7e3e000, 00d7e7e000] swiotlb orig_ad
[ 0.000000] memblock_x86_reserve_range: [000008a000, 0000092000] swiotlb overflo
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We don't need to export io_tlb_overflow_buffer. I'll remove
io_tlb_overflow_buffer completely in the long term though.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We put the functions dealing with the operations on
the SWIOTLB buffer in the header and make those functions non-static.
And also make the functions exported via EXPORT_SYMBOL_GPL.
See "swiotlb: swiotlb: add swiotlb_tbl_map_single library function" for
full description of patchset.
[v2: swiotlb_sync_single_range_for_* no more. Remove usage.]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Albert Herranz <albert_herranz@yahoo.es>
.. to catch anybody doing something funky.
See "swiotlb: swiotlb: add swiotlb_tbl_map_single library function" for
full description of patchset.
[v2: swiotlb_sync_single_range_* no more - removed usage]
[v3: enum dma_data_direction direction -> enum dma_data_direction dir]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Albert Herranz <albert_herranz@yahoo.es>
The functions that operate on io_tlb_list/io_tlb_start/io_tlb_orig_addr
have the prefix 'swiotlb_tbl' now.
See "swiotlb: swiotlb: add swiotlb_tbl_map_single library function" for
full description of patchset.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Albert Herranz <albert_herranz@yahoo.es>
This enables the caller to initialize swiotlb with its own iotlb
memory.
See "swiotlb: swiotlb: add swiotlb_tbl_map_single library function" for
full description of patchset.
[v2: changed ..with_tlb to ..with_tbl]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Albert Herranz <albert_herranz@yahoo.es>
swiotlb_tbl_map_single() takes the dma address of iotlb instead of
using swiotlb_virt_to_bus().
[v2: changed swiotlb_tlb to swiotlb_tbl]
[v3: changed u64 to dma_addr_t]
This patch:
This is a set of patches that separate the address translation
(virt_to_phys, virt_to_bus, etc) and allocation of the SWIOTLB buffer
from the SWIOTLB library.
The idea behind this set of patches is to make it possible to have separate
mechanisms for translating virtual to physical or virtual to DMA addresses
on platforms which need an SWIOTLB, and where physical != PCI bus address
and also to allocate the core IOTLB memory outside SWIOTLB.
One customers of this is the pv-ops project, which can switch between
different modes of operation depending on the environment it is running in:
bare-metal or virtualized (Xen for now). Another is the Wii DMA - used to
implement the MEM2 DMA facility needed by its EHCI controller (for details:
http://lkml.org/lkml/2010/5/18/303)
On bare-metal SWIOTLB is used when there are no hardware IOMMU. In virtualized
environment it used when PCI pass-through is enabled for the guest. The problems
with PCI pass-through is that the guest's idea of PFN's is not the real thing.
To fix that, there is translation layer for PFN->machine frame number and vice-versa.
To bubble that up to the SWIOTLB layer there are two possible solutions.
One solution has been to wholesale copy the SWIOTLB, stick it in
arch/x86/xen/swiotlb.c and modify the virt_to_phys, phys_to_virt and others
to use the Xen address translation functions. Unfortunately, since the kernel can
run on bare-metal, there would be big code overlap with the real SWIOTLB.
(git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git xen/dom0/swiotlb-new)
Another approach, which this set of patches explores, is to abstract the
address translation and address determination functions away from the
SWIOTLB book-keeping functions. This way the core SWIOTLB library functions
are present in one place, while the address related functions are in
a separate library that can be loaded when running under non-bare-metal platform.
Changelog:
Since the last posting [v8.2] Konrad has done:
- Added this changelog in the patch and referenced in the other patches
this description.
- 'enum dma_data_direction direction' to 'enum dma.. dir' so to be
unified.
[v8-v8.2 changes:]
- Rolled-up the last two patches in one.
- Rebased against linus latest. That meant dealing with swiotlb_sync_single_range_* changes.
- added Acked-by: Fujita Tomonori and Tested-by: Albert Herranz
[v7-v8 changes:]
- Minimized the list of exported functions.
- Integrated Fujita's patches and changed "swiotlb_tlb" to "swiotlb_tbl" in them.
[v6-v7 changes:]
- Minimized the amount of exported functions/variable with a prefix of: "swiotbl_tbl".
- Made the usage of 'int dir' to be 'enum dma_data_direction'.
[v5-v6 changes:]
- Made the exported functions/variables have the 'swiotlb_bk' prefix.
- dropped the checkpatches/other reworks
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Albert Herranz <albert_herranz@yahoo.es>