Due to a design incompatibility between the PCIe Marvell controller
and the Cortex-A9, stressing PCIe devices with a lot of traffic
quickly causes a deadlock.
One part of the workaround for this is to have all PCIe regions mapped
as strongly-ordered (MT_UNCACHED) instead of the default
MT_DEVICE. While the arch_ioremap_caller() mechanism allows
sub-architecture code to override ioremap(), used to map PCIe memory
regions, there isn't such a mechanism to override the behavior of
pci_ioremap_io().
This commit adds the arch_pci_ioremap_mem_type variable, initialized
to MT_DEVICE by default, and that sub-architecture code can
override. We have chosen to expose a single variable rather than
offering the possibility of overriding the entire pci_ioremap_io(),
because implementing pci_ioremap_io() requires calling functions
(get_mem_type()) that are private to the arch/arm/mm/ code.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Several of the ioremap functions use unsigned long in places
resulting in truncation if physical addresses greater than
4G are passed in. Change the types of the functions and the
callers accordingly.
Cc: Krzysztof Halasa <khc@pm.waw.pl>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
A static mapped area is ARM-specific, so it is better not to use
generic vmalloc data structure, that is, vmlist and vmlist_lock
for managing static mapped area. And it causes some needless overhead and
reducing this overhead is better idea.
Now, we have newly introduced static_vm infrastructure.
With it, we don't need to iterate all mapped areas. Instead, we just
iterate static mapped areas. It helps to reduce an overhead of finding
matched area. And architecture dependency on vmalloc layer is removed,
so it will help to maintainability for vmalloc layer.
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In current implementation, we used ARM-specific flag, that is,
VM_ARM_STATIC_MAPPING, for distinguishing ARM specific static mapped area.
The purpose of static mapped area is to re-use static mapped area when
entire physical address range of the ioremap request can be covered
by this area.
This implementation causes needless overhead for some cases.
For example, assume that there is only one static mapped area and
vmlist has 300 areas. Every time we call ioremap, we check 300 areas for
deciding whether it is matched or not. Moreover, even if there is
no static mapped area and vmlist has 300 areas, every time we call
ioremap, we check 300 areas in now.
If we construct a extra list for static mapped area, we can eliminate
above mentioned overhead.
With a extra list, if there is one static mapped area,
we just check only one area and proceed next operation quickly.
In fact, it is not a critical problem, because ioremap is not frequently
used. But reducing overhead is better idea.
Another reason for doing this work is for removing architecture dependency
on vmalloc layer. I think that vmlist and vmlist_lock is internal data
structure for vmalloc layer. Some codes for debugging and stat inevitably
use vmlist and vmlist_lock. But it is preferable that they are used
as least as possible in outside of vmalloc.c
Now, I introduce an ARM-specific infrastructure for static mapped area. In
the following patch, we will use this and resolve above mentioned problem.
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The kvm_seq value has nothing to do what so ever with this other KVM.
Given that KVM support on ARM is imminent, it's best to rename kvm_seq
into something else to clearly identify what it is about i.e. a sequence
number for vmalloc section mappings.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM updates from Russell King:
"This is the first chunk of ARM updates for this merge window.
Conflicts are expected in two files - asm/timex.h and
mach-integrator/integrator_cp.c. Nothing particularly stands out more
than anything else.
Most of the growth is down to the opcodes stuff from Dave Martin,
which is countered by Rob's patches to use more of the asm-generic
headers on ARM."
(A few more conflicts grew since then, but it all looked fairly trivial)
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (44 commits)
ARM: 7548/1: include linux/sched.h in syscall.h
ARM: 7541/1: Add ARM ERRATA 775420 workaround
ARM: ensure vm_struct has its phys_addr member filled in
ARM: 7540/1: kexec: Check segment memory addresses
ARM: 7539/1: kexec: scan for dtb magic in segments
ARM: 7538/1: delay: add registration mechanism for delay timer sources
ARM: 7536/1: smp: Formalize an IPI for wakeup
ARM: 7525/1: ptrace: use updated syscall number for syscall auditing
ARM: 7524/1: support syscall tracing
ARM: 7519/1: integrator: convert platform devices to Device Tree
ARM: 7518/1: integrator: convert AMBA devices to device tree
ARM: 7517/1: integrator: initial device tree support
ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ
ARM: 7515/1: integrator: check PL010 base address from resource
ARM: 7514/1: integrator: call common init function from machine
ARM: 7522/1: arch_timers: register a time/cycle counter
ARM: 7523/1: arch_timers: enable the use of the virtual timer
ARM: 7531/1: mark kernelmode mem{cpy,set} non-experimental
ARM: 7520/1: Build dtb files in all target
ARM: Fix build warning in arch/arm/mm/alignment.c
...
This allows /proc/vmallocinfo to show the physical address for
ioremap mappings.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
From Rob Herring <robherring2@gmail.com>:
This is the 2nd part of mach/io.h removals. This series removes io.h on
platforms with PCI by creating a fixed virtual I/O mapping and a common
__io() macro.
This version has changed a bit to accommodate Tegra converting its PCIe
host to a platform driver. Now the virtual space is only reserved during
early boot before .map_io() is called. The mapping is not created until
calling pci_ioremap_io which can be done at any point after vmalloc is
initialized.
I've gone back to fixed 64K windows for each PCI bus. This allows
removing all the i/o resource setup from the individually platforms and
placing it within the common ARM PCI code.
I've only tested versatilepb under qemu (with the model hacked up to
actually enable i/o space), so any testing is appreciated. iop3xx and
mv78xx0 have some risk of breaking as the PCI bus addresses are moved
to 0 from matching the cpu host bus addesss.
* cleanup/io-pci:
ARM: iop3xx: use fixed PCI i/o mapping
ARM: mv78xx0: use fixed pci i/o mapping
ARM: iop13xx: use fixed PCI i/o mapping
iop13xx: use more regular PCI I/O space handling
ARM: orion5x: use fixed PCI i/o mapping
ARM: kirkwood: use fixed PCI i/o mapping
ARM: dove: use fixed PCI i/o mapping
ARM: footbridge: use fixed PCI i/o mapping
ARM: shark: use fixed PCI i/o mapping
ARM: integrator: remove trailing whitespace on pci_v3.c
ARM: integrator: use fixed PCI i/o mapping
ARM: tegra: use fixed PCI i/o mapping
ARM: versatile: use fixed PCI i/o mapping
ARM: move PCI i/o resource setup into common code
ARM: Add fixed PCI i/o mapping
i2c: iop3xx: use standard gpiolib functions
i2c: iop3xx: clean-up trailing whitespace
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This adds a fixed virtual mapping for PCI i/o addresses. The mapping is
located at the last 2MB of vmalloc region (0xfee00000-0xff000000). 2MB
is used to align with PMD size, but IO_SPACE_LIMIT is 1MB. The space
is reserved after .map_io and can be mapped at any time later with
pci_ioremap_io. Platforms which need early i/o mapping (e.g. for vga
console) can call pci_map_io_early in their .map_io function.
This has changed completely from the 1st implementation which only
supported creating the static mapping at .map_io.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org>
Rob Herring has done a sweeping change cleaning up all of the mach/io.h includes,
moving some of the oft-repeated macros to a common location and removing a bunch of
boiler plate. This is another step closer to a common zImage for multiple platforms.
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Merge tag 'cleanup2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull "ARM: cleanups of io includes" from Olof Johansson:
"Rob Herring has done a sweeping change cleaning up all of the
mach/io.h includes, moving some of the oft-repeated macros to a common
location and removing a bunch of boiler plate. This is another step
closer to a common zImage for multiple platforms."
Fix up various fairly trivial conflicts (<mach/io.h> removal vs changes
around it, tegra localtimer.o is *still* gone, yadda-yadda).
* tag 'cleanup2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (29 commits)
ARM: tegra: Include assembler.h in sleep.S to fix build break
ARM: pxa: use common IOMEM definition
ARM: dma-mapping: convert ARCH_HAS_DMA_SET_COHERENT_MASK to kconfig symbol
ARM: __io abuse cleanup
ARM: create a common IOMEM definition
ARM: iop13xx: fix missing declaration of iop13xx_init_early
ARM: fix ioremap/iounmap for !CONFIG_MMU
ARM: kill off __mem_pci
ARM: remove bunch of now unused mach/io.h files
ARM: make mach/io.h include optional
ARM: clps711x: remove unneeded include of mach/io.h
ARM: dove: add explicit include of dove.h to addr-map.c
ARM: at91: add explicit include of hardware.h to uncompressor
ARM: ep93xx: clean-up mach/io.h
ARM: tegra: clean-up mach/io.h
ARM: orion5x: clean-up mach/io.h
ARM: davinci: remove unneeded mach/io.h include
[media] davinci: remove includes of mach/io.h
ARM: OMAP: Remove remaining includes for mach/io.h
ARM: msm: clean-up mach/io.h
...
Disintegrate asm/system.h for ARM.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org
Avoid namespace conflicts with drivers over the CP15 definitions by
moving CP15 related prototypes and definitions to a private header
file.
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com> [Tegra]
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com> [EP93xx]
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
We have compile time over-ride of ioremap and iounmap, but an run-time
override is needed for multi-platform builds. This adds an extra function
pointer check, but ioremap is not peformance critical. The option for
compile time selection remains.
The caller variant is used here to provide correct caller information as
ARM can only support level 0 for __builtin_return_address.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
This reverts commit 3c424f3598.
Joachim Eastwood reports:
| "ARM: 7304/1: ioremap: fix boundary check when reusing static mapping"
| Commit: 3c424f3598 in Linus master
|
| Breaks booting on my custom AT91RM9200 board.
| There isn't any error messages or anything that indicates what goes
| wrong it just stops after; Uncompressing Linux... done, booting the
| kernel.
|
| Reverting it makes my board boot again.
and further debugging reveals:
ioremap: pfn=fffff phys=fffff000 offset=400 size=1000
ioremap: area c3ffdfc0: phys_addr=200000 pfn=200 size=4000
ioremap: found: addr fef74000 => fed73000 => fed73400
Clearly, an area for pfn 0x200, 16K can't ever satisfy a request for pfn
0xfffff. This happens because the changed if statement becomes:
if (0x00200 > 0xfffff ||
0xfffff000 + 0x400 + 0x1000-1 > 0x00200000 + 0x4000-1)
and therefore:
if (0x00200 > 0xfffff ||
0x000003ff > 0x00203fff)
The if condition fails, and so we _believe_ that the SRAM mapping fits
our request. Clearly that's totally bogus.
Moreover, the original premise of the 'fix' patch was wrong:
| The condition checking boundaries of the requested and existing
| mappings didn't take in-page offset into consideration though,
| which lead to obscure and hard to debug problems when requested
| mapping crossed end of the static one.
as the code immediately above this loop does:
size = PAGE_ALIGN(offset + size);
so 'size' already contains the requested offset into the page.
So, revert the broken 'fix'.
Acked-by: Nicolas Pitre <nico@linaro.org>
Since commit 576d2f2525 "ARM: add
generic ioremap optimization by reusing static mappings" ioremap()
is trying to reuse existing static mapping when possible.
The condition checking boundaries of the requested and existing
mappings didn't take in-page offset into consideration though,
which lead to obscure and hard to debug problems when requested
mapping crossed end of the static one.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch modifies the pgd/pmd/pte manipulation functions to support
the 3-level page table format. Since there is no need for an 'ext'
argument to cpu_set_pte_ext(), this patch conditionally defines a
different prototype for this function when CONFIG_ARM_LPAE.
The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries
pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid
trying to free them at run-time. This flag is 0 with the classic page
table format.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
With the arch/arm code conversion to pgtable-nopud.h, the section and
supersection (un|re)map code triggers compiler warnings on UP systems.
This is caused by pmd_offset() being given a pgd_t argument rather than
a pud_t one. This patch makes the necessary conversion with the
assumption that the pud is folded into the pgd. The page table setting
code only loops over the pmd which is enough with the classic page
tables. This code is not compiled when LPAE is enabled.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Now that we have all the static mappings from iotable_init() located
in the vmalloc area, it is trivial to optimize ioremap by reusing those
static mappings when the requested physical area fits in one of them,
and so in a generic way for all platforms.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Tested-by: Jamie Iles <jamie@jamieiles.com>
Firstly, there is no need to have a double pointer here as we're only
walking the vmlist and not modifying it.
Secondly, for the same reason, we don't need a write lock but only a
read lock here, since the lock only protects the coherency of the list
nothing else.
Lastly, the reason for holding a lock is not what the comment says, so
let's remove that misleading piece of information.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
This allows mapping external memory such as SRAM for use.
This is needed for some small chunks of code, such as reprogramming
SDRAM memory source clocks that can't be executed in SDRAM. Other
use cases include some PM related code.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
... but produce a big warning about the problem as encouragement
for people to fix their drivers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We don't need our own implementation of this, use the generic
library implementation instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv6 and above have a restriction whereby aliasing virtual:physical
mappings must not have differing memory type and sharability
attributes. Strictly, this covers the memory type (strongly ordered,
device, memory), cache attributes (uncached, write combine, write
through, write back read alloc, write back write alloc) and the
shared bit.
However, using ioremap() and its variants on system RAM results in
mappings which differ in these attributes from the main system RAM
mapping. Other architectures which similar restrictions approch this
problem in the same way - they do not permit ioremap on main system
RAM.
Make ARM behave in the same way, with a WARN_ON() such that users can
be traced and an alternative approach found.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows the procfs vmallocinfo file to show who created the ioremap
regions. Note: __builtin_return_address(0) doesn't do what's expected
if its used in an inline function, so we leave __arm_ioremap callers
in such places alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch provides a device drivers, which has a omap iommu, with
address mapping APIs between device virtual address(iommu), physical
address and MPU virtual address.
There are 4 possible patterns for iommu virtual address(iova/da) mapping.
|iova/ mapping iommu_ page
| da pa va (d)-(p)-(v) function type
---------------------------------------------------------------------------
1 | c c c 1 - 1 - 1 _kmap() / _kunmap() s
2 | c c,a c 1 - 1 - 1 _kmalloc()/ _kfree() s
3 | c d c 1 - n - 1 _vmap() / _vunmap() s
4 | c d,a c 1 - n - 1 _vmalloc()/ _vfree() n*
'iova': device iommu virtual address
'da': alias of 'iova'
'pa': physical address
'va': mpu virtual address
'c': contiguous memory area
'd': dicontiguous memory area
'a': anonymous memory allocation
'()': optional feature
'n': a normal page(4KB) size is used.
's': multiple iommu superpage(16MB, 1MB, 64KB, 4KB) size is used.
'*': not yet, but feasible.
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Tomi Valkeinen reports:
Running with latest linux-omap kernel on OMAP3 SDP board, I have
problem with iounmap(). It looks like iounmap() does not properly
free large areas. Below is a test which fails for me in 6-7 loops.
for (i = 0; i < 200; ++i) {
vaddr = ioremap(paddr, size);
if (!vaddr) {
printk("couldn't ioremap\n");
break;
}
iounmap(vaddr);
}
The changes to vmalloc.c weren't reflected in the ARM ioremap
implementation. Turns out the fix is rather simple.
Tested-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Tested-by: Matt Gerassimoff <mgeras@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/process.c:270:6: warning: symbol 'show_fpregs' was not declared. Should it be static?
This function isn't used, so can be removed.
arch/arm/kernel/setup.c:532:9: warning: symbol 'len' shadows an earlier one
arch/arm/kernel/setup.c:524:6: originally declared here
A function containing two 'len's.
arch/arm/mm/fault-armv.c:188:13: warning: symbol 'check_writebuffer_bugs' was not declared. Should it be static?
arch/arm/mm/mmap.c:122:5: warning: symbol 'valid_phys_addr_range' was not declared. Should it be static?
arch/arm/mm/mmap.c:137:5: warning: symbol 'valid_mmap_phys_addr_range' was not declared. Should it be static?
Missing includes.
arch/arm/kernel/traps.c:71:77: warning: Using plain integer as NULL pointer
arch/arm/mm/ioremap.c:355:46: error: incompatible types in comparison expression (different address spaces)
Sillies.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add asm/cputype.h, moving functions and definitions from asm/system.h
there. Convert all users of 'processor_id' to the more efficient
read_cpuid_id() function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
(with Martin Schwidefsky <schwidefsky@de.ibm.com>)
The pgd/pud/pmd/pte page table allocation functions get a mm_struct pointer as
first argument. The free functions do not get the mm_struct argument. This
is 1) asymmetrical and 2) to do mm related page table allocations the mm
argument is needed on the free function as well.
[kamalesh@linux.vnet.ibm.com: i386 fix]
[akpm@linux-foundation.org: coding-syle fixes]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__ioremap() took a set of page table flags (specifically the cacheable
and bufferable bits) to control the mapping type. However, with
the advent of ARMv6, this is far too limited.
Replace the page table flags with a memory type index, so that the
desired attributes can be selected from the mem_type table.
Finally, to prevent silent miscompilation due to the differing
arguments, rename the __ioremap() and __ioremap_pfn() functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add prot_pte_ext to the mem_types table to allow the extended pte
attributes to be passed to set_pte_ext(), thereby permitting us to
specify memory type information for the hardware PTE entries.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We really want to be using the memory type table in ioremap, so we
only have to do the CPU type fixups in one place.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Catalin Marinas at ARM Ltd says:
> The CPU architects in ARM intended supersections only as a way to map
> addresses >= 4GB. Supersections are not mandated by the architecture
> and there is no easy way to detect their hardware support at run-time
> (other than checking for a specific core). From the analysis done in
> ARM, there wasn't a clear performance gain by using supersections
> rather than sections (no significant improvement in the TLB misses).
Therefore, we should avoid using supersections unless there's a real
need (iow, we're mapping addresses >= 4GB).
This means that we can simplify create_mapping() a bit since we will
only use supersection mappings for addresses >= 4GB, which means that
the physical, virtual and length must be multiples of the supersection
mapping size.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Supersections do not have a field for the domain and it is always
0. This patch prevents the creation of supersections during ioremap
when DOMAIN_IO is not zero (i.e. !defined(CONFIG_IO_36)).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We need to ensure that the area size is page aligned so that
remap_area_pte() doesn't increment the address past the end of
the desired area.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since we're keeping the ioremap code, we might as well keep it as
close to the standard kernel as possible.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
L_PTE_ASID is not really required to be stored in every PTE, since we
can identify it via the address passed to set_pte_at(). So, create
set_pte_ext() which takes the address of the PTE to set, the Linux
PTE value, and the additional CPU PTE bits which aren't encoded in
the Linux PTE value.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
One of the changes necessary for shared page tables is to standardize the
pxx_page macros. pte_page and pmd_page have always returned the struct
page associated with their entry, while pte_page_kernel and pmd_page_kernel
have returned the kernel virtual address. pud_page and pgd_page, on the
other hand, return the kernel virtual address.
Shared page tables needs pud_page and pgd_page to return the actual page
structures. There are very few actual users of these functions, so it is
simple to standardize their usage.
Since this is basic cleanup, I am submitting these changes as a standalone
patch. Per Hugh Dickins' comments about it, I am also changing the
pxx_page_kernel macros to pxx_page_vaddr to clarify their meaning.
Signed-off-by: Dave McCracken <dmccr@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch from Catalin Marinas
This patch adds #ifdef around some variables in the arch/arm/mm/ioremap.c
file.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
