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mm: fault feedback #2

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This patch completes Linus's wish that the fault return codes be made into
bit flags, which I agree makes everything nicer.  This requires requires
all handle_mm_fault callers to be modified (possibly the modifications
should go further and do things like fault accounting in handle_mm_fault --
however that would be for another patch).

[akpm@linux-foundation.org: fix alpha build]
[akpm@linux-foundation.org: fix s390 build]
[akpm@linux-foundation.org: fix sparc build]
[akpm@linux-foundation.org: fix sparc64 build]
[akpm@linux-foundation.org: fix ia64 build]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Still apparently needs some ARM and PPC loving - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Nick Piggin
2007-07-19 01:47:05 -07:00
committed by Linus Torvalds
parent d0217ac04c
commit 83c54070ee
32 changed files with 376 additions and 422 deletions
Download Patch File Download Diff File Expand all files Collapse all files

80
mm/memory.c
View File

@ -1068,31 +1068,30 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
cond_resched();
while (!(page = follow_page(vma, start, foll_flags))) {
int ret;
ret = __handle_mm_fault(mm, vma, start,
ret = handle_mm_fault(mm, vma, start,
foll_flags & FOLL_WRITE);
if (ret & VM_FAULT_ERROR) {
if (ret & VM_FAULT_OOM)
return i ? i : -ENOMEM;
else if (ret & VM_FAULT_SIGBUS)
return i ? i : -EFAULT;
BUG();
}
if (ret & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
/*
* The VM_FAULT_WRITE bit tells us that do_wp_page has
* broken COW when necessary, even if maybe_mkwrite
* decided not to set pte_write. We can thus safely do
* subsequent page lookups as if they were reads.
* The VM_FAULT_WRITE bit tells us that
* do_wp_page has broken COW when necessary,
* even if maybe_mkwrite decided not to set
* pte_write. We can thus safely do subsequent
* page lookups as if they were reads.
*/
if (ret & VM_FAULT_WRITE)
foll_flags &= ~FOLL_WRITE;
switch (ret & ~VM_FAULT_WRITE) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
case VM_FAULT_MAJOR:
tsk->maj_flt++;
break;
case VM_FAULT_SIGBUS:
return i ? i : -EFAULT;
case VM_FAULT_OOM:
return i ? i : -ENOMEM;
default:
BUG();
}
cond_resched();
}
if (pages) {
@ -1639,7 +1638,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
{
struct page *old_page, *new_page;
pte_t entry;
int reuse = 0, ret = VM_FAULT_MINOR;
int reuse = 0, ret = 0;
struct page *dirty_page = NULL;
old_page = vm_normal_page(vma, address, orig_pte);
@ -1835,8 +1834,8 @@ static int unmap_mapping_range_vma(struct vm_area_struct *vma,
/*
* files that support invalidating or truncating portions of the
* file from under mmaped areas must have their ->fault function
* return a locked page (and FAULT_RET_LOCKED code). This provides
* synchronisation against concurrent unmapping here.
* return a locked page (and set VM_FAULT_LOCKED in the return).
* This provides synchronisation against concurrent unmapping here.
*/
again:
@ -2140,7 +2139,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
struct page *page;
swp_entry_t entry;
pte_t pte;
int ret = VM_FAULT_MINOR;
int ret = 0;
if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
goto out;
@ -2208,8 +2207,9 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
unlock_page(page);
if (write_access) {
/* XXX: We could OR the do_wp_page code with this one? */
if (do_wp_page(mm, vma, address,
page_table, pmd, ptl, pte) == VM_FAULT_OOM)
page_table, pmd, ptl, pte) & VM_FAULT_OOM)
ret = VM_FAULT_OOM;
goto out;
}
@ -2280,7 +2280,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
lazy_mmu_prot_update(entry);
unlock:
pte_unmap_unlock(page_table, ptl);
return VM_FAULT_MINOR;
return 0;
release:
page_cache_release(page);
goto unlock;
@ -2323,11 +2323,11 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
if (likely(vma->vm_ops->fault)) {
ret = vma->vm_ops->fault(vma, &vmf);
if (unlikely(ret & (VM_FAULT_ERROR | FAULT_RET_NOPAGE)))
return (ret & VM_FAULT_MASK);
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
return ret;
} else {
/* Legacy ->nopage path */
ret = VM_FAULT_MINOR;
ret = 0;
vmf.page = vma->vm_ops->nopage(vma, address & PAGE_MASK, &ret);
/* no page was available -- either SIGBUS or OOM */
if (unlikely(vmf.page == NOPAGE_SIGBUS))
@ -2340,7 +2340,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
* For consistency in subsequent calls, make the faulted page always
* locked.
*/
if (unlikely(!(ret & FAULT_RET_LOCKED)))
if (unlikely(!(ret & VM_FAULT_LOCKED)))
lock_page(vmf.page);
else
VM_BUG_ON(!PageLocked(vmf.page));
@ -2356,7 +2356,8 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
ret = VM_FAULT_OOM;
goto out;
}
page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
page = alloc_page_vma(GFP_HIGHUSER_MOVABLE,
vma, address);
if (!page) {
ret = VM_FAULT_OOM;
goto out;
@ -2384,7 +2385,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
* is better done later.
*/
if (!page->mapping) {
ret = VM_FAULT_MINOR;
ret = 0;
anon = 1; /* no anon but release vmf.page */
goto out;
}
@ -2447,7 +2448,7 @@ out_unlocked:
put_page(dirty_page);
}
return (ret & VM_FAULT_MASK);
return ret;
}
static int do_linear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
@ -2486,7 +2487,6 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
spinlock_t *ptl;
pte_t entry;
unsigned long pfn;
int ret = VM_FAULT_MINOR;
pte_unmap(page_table);
BUG_ON(!(vma->vm_flags & VM_PFNMAP));
@ -2498,7 +2498,7 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
else if (unlikely(pfn == NOPFN_SIGBUS))
return VM_FAULT_SIGBUS;
else if (unlikely(pfn == NOPFN_REFAULT))
return VM_FAULT_MINOR;
return 0;
page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
@ -2510,7 +2510,7 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
set_pte_at(mm, address, page_table, entry);
}
pte_unmap_unlock(page_table, ptl);
return ret;
return 0;
}
/*
@ -2531,7 +2531,7 @@ static int do_nonlinear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
pgoff_t pgoff;
if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
return VM_FAULT_MINOR;
return 0;
if (unlikely(!(vma->vm_flags & VM_NONLINEAR) ||
!(vma->vm_flags & VM_CAN_NONLINEAR))) {
@ -2615,13 +2615,13 @@ static inline int handle_pte_fault(struct mm_struct *mm,
}
unlock:
pte_unmap_unlock(pte, ptl);
return VM_FAULT_MINOR;
return 0;
}
/*
* By the time we get here, we already hold the mm semaphore
*/
int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, int write_access)
{
pgd_t *pgd;
@ -2650,7 +2650,7 @@ int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
}
EXPORT_SYMBOL_GPL(__handle_mm_fault);
EXPORT_SYMBOL_GPL(handle_mm_fault);
#ifndef __PAGETABLE_PUD_FOLDED
/*