(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>
Remove bogus reference to "Pentium-II erratum A13" and point to the
actual canonical source of information about what requirements x86
processors have for PAE pagetable updates.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
PAE mode requires that we reload cr3 in order to guarantee that
changes to the pgd will be noticed by the processor. This means that
in principle pud_clear needs to reload cr3 every time. However,
because reloading cr3 implies a tlb flush, we want to avoid it where
possible.
pud_clear() is only used in a couple of places:
- in free_pmd_range(), when pulling down a range of process address space, and
- huge_pmd_unshare()
In both cases, the calling code will do a a tlb flush anyway, so
there's no need to do it within pud_clear().
In free_pmd_range(), the pud_clear is immediately followed by
pmd_free_tlb(); we can hook that to make the mmu_gather do an
unconditional full flush to make sure cr3 gets reloaded.
In huge_pmd_unshare, it is followed by flush_tlb_range, which always
results in a full cr3-reload tlb flush.
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>
In x86 PAE mode, stop treating pmds as a special case. Previously
they were always allocated and freed with the pgd. The modifies the
code to be the same as 64-bit mode, where they are allocated on
demand.
This is a step on the way to unifying 32/64-bit pagetable allocation
as much as possible.
There is a complicating wart, however. When you install a new
reference to a pmd in the pgd, the processor isn't guaranteed to see
it unless you reload cr3. Since reloading cr3 also has the
side-effect of flushing the tlb, this is an expense that we want to
avoid whereever possible.
This patch simply avoids reloading cr3 unless the update is to the
current pagetable. Later patches will optimise this further.
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>
Convert macros into inline functions, for better type-checking.
This patch required a little bit of fiddling with headers in order to
make __(pte|pmd)_free_tlb inline rather than macros.
asm-generic/tlb.h includes asm/pgalloc.h, though it doesn't directly
use any pgalloc definitions. I removed this include to avoid an
include cycle, but it may cause secondary compile failures by things
depending on the indirect inclusion; arch/x86/mm/hugetlbpage.c was one
such place; there may be others.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add mm to paravirt_alloc_pd, partly to make it consistent with
paravirt_alloc_pt, and because later changes will make use of it.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Move the headers to include/asm-x86 and fixup the
header install make rules
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It's useful to know which mm is allocating a pagetable. Xen uses this
to determine whether the pagetable being added to is pinned or not.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
SLUB cannot run on i386 at this point because i386 uses the page->private and
page->index field of slab pages for the pgd cache.
Make SLUB run on i386 by replacing the pgd slab cache with a quicklist.
Limit the changes as much as possible. Leave the improvised linked list in place
etc etc. This has been working here for a couple of weeks now.
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move inclusion of asm/fixmap.h to where it is really used rather than
where it may have been used long ago (requires a few other adjustments
to includes due to previous implicit dependencies).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
The VMI backend uses explicit page type notification to track shadow page
tables. The allocation of page table roots is especially tricky. We need to
clone the root for non-PAE mode while it is protected under the pgd lock to
correctly copy the shadow.
We don't need to allocate pgds in PAE mode, (PDPs in Intel terminology) as
they only have 4 entries, and are cached entirely by the processor, which
makes shadowing them rather simple.
For base page table level allocation, pmd_populate provides the exact hook
point we need. Also, we need to allocate pages when splitting a large page,
and we must release pages before returning the page to any free pool.
Despite being required with these slightly odd semantics for VMI, Xen also
uses these hooks to determine the exact moment when page tables are created or
released.
AK: All nops for other architectures
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Benjamin Herrenschmidt