Thomas Gleixner [Wed, 30 Jan 2008 12:34:06 +0000 (13:34 +0100)]
x86: fix the missing BIOS area check in page_is_ram
page_is_ram has a FIXME since ages, which reminds to sanity check the
BIOS area between 640k and 1M, which is sometimes falsely reported as
RAM in the e820 tables.
Implement the sanity check. Move the BIOS range defines from
pageattr.c into e820.h to avoid duplicate defines.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arjan van de Ven [Wed, 30 Jan 2008 12:34:06 +0000 (13:34 +0100)]
x86: deprecate change_page_attr() for drivers
With the introduction of the new API, no driver or non-archcore code needs
to use c-p-a anymore, so this patch also deprecates the EXPORT_SYMBOL of CPA
(it's a horrible API after all).
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arjan van de Ven [Wed, 30 Jan 2008 12:34:06 +0000 (13:34 +0100)]
x86: a new API for drivers/etc to control cache and other page attributes
Right now, if drivers or other code want to change, say, a cache attribute of a
page, the only API they have is change_page_attr(). c-p-a is a really bad API
for this, because it forces the caller to know *ALL* the attributes he wants
for the page, not just the 1 thing he wants to change. So code that wants to
set a page uncachable, needs to be aware of the NX status as well etc etc etc.
This patch introduces a set of new APIs for this, set_pages_<attr> and
set_memory_<attr>, that offer a logical change to the user, and leave all
attributes not implied by the requested logical change alone.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Thomas Gleixner [Wed, 30 Jan 2008 12:34:05 +0000 (13:34 +0100)]
x86: make c_p_a unconditional in ioremap
Make c_p_a unconditional for ioremap and iounmap. This ensures
complete consistency of the flags which are handed to
ioremap_page_range and the real flags in the mappings.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Thomas Gleixner [Wed, 30 Jan 2008 12:34:05 +0000 (13:34 +0100)]
x86: introduce max_pfn_mapped
64bit uses end_pfn_map and 32bit uses max_low_pfn. There are several
files which have #ifdef'ed defines which map either to end_pfn_map or
max_low_pfn. Replace this by a universal define and clean up all the
other instances.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Thomas Gleixner [Wed, 30 Jan 2008 12:34:05 +0000 (13:34 +0100)]
x86: fix ioremap pgprot inconsistency
The pgprot flags which are handed into ioremap_page_range() are
different to those which are set in change_page_attr(). The
ioremap_page_range flags are executable, while the c_p_a flags are
not.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Thomas Gleixner [Wed, 30 Jan 2008 12:34:04 +0000 (13:34 +0100)]
x86: fix ioremap pgprot inconsistency
The pgprot flags which are handed into ioremap_page_range() are
different to those which are set in change_page_attr(). The
ioremap_page_range flags are executable, while the c_p_a flags are
not. Also make the mappings global (which is a NOP currently on 32bit,
although CPUs from PPRO+ onwards support it, but that's a separate
fix.)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arjan van de Ven [Wed, 30 Jan 2008 12:34:04 +0000 (13:34 +0100)]
x86: turn the check_exec function into function that
What the check_exec() function really is trying to do is enforce certain
bits in the pgprot that are required by the x86 architecture, but that
callers might not be aware of (such as NX bit exclusion of the BIOS
area for BIOS based PCI access; it's not uncommon to ioremap the BIOS
region for various purposes and normally ioremap() memory has the NX bit
set).
This patch turns the check_exec() function into static_protections()
which also is now used to make sure the kernel text area remains non-NX
and that the .rodata section remains read-only. If the architecture
ends up requiring more such mandatory prot settings for specific areas,
this is now a reasonable place to add these.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Huang, Ying [Wed, 30 Jan 2008 12:34:04 +0000 (13:34 +0100)]
x86: ioremap_nocache fix
This patch fixes a bug of ioremap_nocache. ioremap_nocache() will call
__ioremap() with flags != 0 to do the real work, which will call
change_page_attr_addr() if phys_addr + size - 1 < (end_pfn_map << PAGE_SHIFT).
But some pages between 0 ~ end_pfn_map << PAGE_SHIFT are not mapped by
identity map, this will make change_page_attr_addr failed.
This patch is based on latest x86 git and has been tested on x86_64 platform.
Huang, Ying [Wed, 30 Jan 2008 12:34:04 +0000 (13:34 +0100)]
x86: fix NX bit handling in change_page_attr()
This patch fixes a bug of change_page_attr/change_page_attr_addr on
Intel i386/x86_64 CPUs. After changing page attribute to be
executable with these functions, the page remains un-executable on
Intel i386/x86_64 CPU. Because on Intel i386/x86_64 CPU, only if the
"NX" bits of all three level page tables are cleared (PAE is enabled),
the corresponding page is executable (refer to section 4.13.2 of Intel
64 and IA-32 Architectures Software Developer's Manual). So, the bug
is fixed through clearing the "NX" bit of PMD when splitting the huge
PMD.
Andi Kleen [Wed, 30 Jan 2008 12:33:54 +0000 (13:33 +0100)]
x86: fix early_ioremap() on 64-bit
Fix early_ioremap() on x86-64
I had ACPI failures on several machines since a few days. Symptom
was NUMA nodes not getting detected or worse cores not getting detected.
They all came from ACPI not being able to read various of its tables. I finally
bisected it down to Jeremy's "put _PAGE_GLOBAL into PAGE_KERNEL" change.
With that the fix was fairly obvious. The problem was that early_ioremap()
didn't use a "_all" flush that would affect the global PTEs too. So
with global bits getting used everywhere now an early_ioremap would
not actually flush a mapping if something else was mapped previously
on that slot (which can happen with early_iounmap inbetween)
This patch changes all flushes in init_64.c to be __flush_tlb_all()
and fixes the problem here.
Andi Kleen [Wed, 30 Jan 2008 12:33:53 +0000 (13:33 +0100)]
x86: remove set_kernel_exec()
The SMP trampoline always runs in real mode, so making it executable
in the page tables doesn't make much sense because it executes
before page tables are set up. That was the only user of
set_kernel_exec(). Remove set_kernel_exec().
Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Andi Kleen [Wed, 30 Jan 2008 12:33:52 +0000 (13:33 +0100)]
x86: c_p_a() make it more robust against use of PAT bits
Use the page table level instead of the PSE bit to check if the PTE
is for a 4K page or not. This makes the code more robust when the PAT
bit is changed because the PAT bit on 4K pages is in the same position
as the PSE bit.
Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Intel recommends to first flush the TLBs and then the caches
on caching attribute changes. c_p_a() previously did it the
other way round. Reorder that.
The procedure is still not fully compliant to the Intel documentation
because Intel recommends a all CPU synchronization step between
the TLB flushes and the cache flushes.
However on all new Intel CPUs this is now meaningless anyways
because they support Self-Snoop and can skip the cache flush
step anyway.
[ mingo@elte.hu: decoupled from clflush and ported it to x86.git ]
Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Andi Kleen [Wed, 30 Jan 2008 12:33:51 +0000 (13:33 +0100)]
x86: don't drop NX bit in pte modifier functions on 32-bit
The pte_* modifier functions that cleared bits dropped the NX bit on 32bit
PAE because they only worked in int, but NX is in bit 63. Fix that
by adding appropiate casts so that the arithmetic happens as long long
on PAE kernels.
I decided to just use 64bit arithmetic instead of open coding like
pte_modify() because gcc should generate good enough code for that now.
Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Ingo Molnar [Wed, 30 Jan 2008 12:33:48 +0000 (13:33 +0100)]
x86: fix early_ioremap()/btmap
fix a long-standing weakness of the early-ioremap allocator: it
uses a single pgd entry for the boot mappings, and was not properly
protecting itself against crossing a 2MB (4MB) boundary.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Huang, Ying [Wed, 30 Jan 2008 12:33:44 +0000 (13:33 +0100)]
i386 boot: replace boot_ioremap with enhanced bt_ioremap - enhance bt_ioremap
This patch makes it possible for bt_ioremap() to be used before
paging_init(), via providing an early implementation of set_fixmap()
that can be used before paging_init().
This way boot_ioremap() can be replaced by bt_ioremap().
Siddha, Suresh B [Wed, 30 Jan 2008 12:33:43 +0000 (13:33 +0100)]
x86: set strong uncacheable where UC is really desired
Also use _PAGE_PWT for all the mappings which need uncache mapping.
Instead of existing PAT2 which is UC- (and can be overwritten by MTRRs),
we now use PAT3 which is strong uncacheable.
Andi Kleen [Wed, 30 Jan 2008 12:33:43 +0000 (13:33 +0100)]
x86: c_p_a(), add simple self test at boot
Since change_page_attr() is tricky code it is good to have some regression
test code. This patch maps and unmaps some random pages in the direct mapping
at boot and then dumps the state and does some simple sanity checks.
Add it with a CONFIG option.
Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Ingo Molnar [Wed, 30 Jan 2008 12:33:43 +0000 (13:33 +0100)]
x86: return the page table level in lookup_address()
based on this patch from Andi Kleen:
| Subject: CPA: Return the page table level in lookup_address()
| From: Andi Kleen <ak@suse.de>
|
| Needed for the next change.
|
| And change all the callers.
and ported it to x86.git.
Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Andi Kleen [Wed, 30 Jan 2008 12:33:42 +0000 (13:33 +0100)]
x86: clean up pte_exec
- Rename it to pte_exec() from pte_exec_kernel(). There is nothing
kernel specific in there.
- Move it into the common file because _PAGE_NX is 0 on !PAE and then
pte_exec() will be always evaluate to true.
Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If SHARED_KERNEL_PMD is false, then we need to allocate and initialize
the kernel pmd. We can easily piggy-back this onto the existing pmd
prepopulation code.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In PAE mode, an update to the pgd requires a cr3 reload to make sure
the processor notices the changes. Since this also has the
side-effect of flushing the tlb, its an expensive operation which we
want to avoid where possible.
This patch mitigates the cost of installing the initial set of pmds on
process creation by preallocating them when the pgd is allocated.
This avoids up to three tlb flushes during exec, as it creates the new
process address space while the pagetable is in active use.
The pmds will be freed as part of the normal pagetable teardown in
free_pgtables, which is called in munmap and process exit. However,
free_pgtables will only free parts of the pagetable which actually
contain mappings, so stray pmds may still be attached to the pgd at
pgd_free time. We must mop them up to prevent a memory leak.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Andi Kleen <ak@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: William Irwin <wli@holomorphy.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
projects / linux-2.6 / log