mirror of
https://github.com/torvalds/linux.git
synced 2024-09-20 15:03:04 +00:00
nommu: fix a number of issues with the per-MM VMA patch
Fix a number of issues with the per-MM VMA patch: (1) Make mmap_pages_allocated an atomic_long_t, just in case this is used on a NOMMU system with more than 2G pages. Makes no difference on a 32-bit system. (2) Report vma->vm_pgoff * PAGE_SIZE as a 64-bit value, not a 32-bit value, lest it overflow. (3) Move the allocation of the vm_area_struct slab back for fork.c. (4) Use KMEM_CACHE() for both vm_area_struct and vm_region slabs. (5) Use BUG_ON() rather than if () BUG(). (6) Make the default validate_nommu_regions() a static inline rather than a #define. (7) Make free_page_series()'s objection to pages with a refcount != 1 more informative. (8) Adjust the __put_nommu_region() banner comment to indicate that the semaphore must be held for writing. (9) Limit the number of warnings about munmaps of non-mmapped regions. Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
5482415a5e
commit
33e5d76979
|
@ -120,7 +120,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
|
||||||
K(i.freeram-i.freehigh),
|
K(i.freeram-i.freehigh),
|
||||||
#endif
|
#endif
|
||||||
#ifndef CONFIG_MMU
|
#ifndef CONFIG_MMU
|
||||||
K((unsigned long) atomic_read(&mmap_pages_allocated)),
|
K((unsigned long) atomic_long_read(&mmap_pages_allocated)),
|
||||||
#endif
|
#endif
|
||||||
K(i.totalswap),
|
K(i.totalswap),
|
||||||
K(i.freeswap),
|
K(i.freeswap),
|
||||||
|
|
|
@ -136,14 +136,14 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
|
||||||
}
|
}
|
||||||
|
|
||||||
seq_printf(m,
|
seq_printf(m,
|
||||||
"%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
|
"%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
|
||||||
vma->vm_start,
|
vma->vm_start,
|
||||||
vma->vm_end,
|
vma->vm_end,
|
||||||
flags & VM_READ ? 'r' : '-',
|
flags & VM_READ ? 'r' : '-',
|
||||||
flags & VM_WRITE ? 'w' : '-',
|
flags & VM_WRITE ? 'w' : '-',
|
||||||
flags & VM_EXEC ? 'x' : '-',
|
flags & VM_EXEC ? 'x' : '-',
|
||||||
flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
|
flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
|
||||||
vma->vm_pgoff << PAGE_SHIFT,
|
(unsigned long long) vma->vm_pgoff << PAGE_SHIFT,
|
||||||
MAJOR(dev), MINOR(dev), ino, &len);
|
MAJOR(dev), MINOR(dev), ino, &len);
|
||||||
|
|
||||||
if (file) {
|
if (file) {
|
||||||
|
|
|
@ -1079,7 +1079,7 @@ static inline void setup_per_cpu_pageset(void) {}
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
/* nommu.c */
|
/* nommu.c */
|
||||||
extern atomic_t mmap_pages_allocated;
|
extern atomic_long_t mmap_pages_allocated;
|
||||||
|
|
||||||
/* prio_tree.c */
|
/* prio_tree.c */
|
||||||
void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old);
|
void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old);
|
||||||
|
|
|
@ -1488,6 +1488,7 @@ void __init proc_caches_init(void)
|
||||||
mm_cachep = kmem_cache_create("mm_struct",
|
mm_cachep = kmem_cache_create("mm_struct",
|
||||||
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
|
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
|
||||||
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
|
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
|
||||||
|
vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC);
|
||||||
mmap_init();
|
mmap_init();
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
|
@ -2481,7 +2481,4 @@ void mm_drop_all_locks(struct mm_struct *mm)
|
||||||
*/
|
*/
|
||||||
void __init mmap_init(void)
|
void __init mmap_init(void)
|
||||||
{
|
{
|
||||||
vm_area_cachep = kmem_cache_create("vm_area_struct",
|
|
||||||
sizeof(struct vm_area_struct), 0,
|
|
||||||
SLAB_PANIC, NULL);
|
|
||||||
}
|
}
|
||||||
|
|
52
mm/nommu.c
52
mm/nommu.c
|
@ -69,7 +69,7 @@ int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
|
||||||
int sysctl_nr_trim_pages = 1; /* page trimming behaviour */
|
int sysctl_nr_trim_pages = 1; /* page trimming behaviour */
|
||||||
int heap_stack_gap = 0;
|
int heap_stack_gap = 0;
|
||||||
|
|
||||||
atomic_t mmap_pages_allocated;
|
atomic_long_t mmap_pages_allocated;
|
||||||
|
|
||||||
EXPORT_SYMBOL(mem_map);
|
EXPORT_SYMBOL(mem_map);
|
||||||
EXPORT_SYMBOL(num_physpages);
|
EXPORT_SYMBOL(num_physpages);
|
||||||
|
@ -463,12 +463,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
|
||||||
*/
|
*/
|
||||||
void __init mmap_init(void)
|
void __init mmap_init(void)
|
||||||
{
|
{
|
||||||
vm_region_jar = kmem_cache_create("vm_region_jar",
|
vm_region_jar = KMEM_CACHE(vm_region, SLAB_PANIC);
|
||||||
sizeof(struct vm_region), 0,
|
|
||||||
SLAB_PANIC, NULL);
|
|
||||||
vm_area_cachep = kmem_cache_create("vm_area_struct",
|
|
||||||
sizeof(struct vm_area_struct), 0,
|
|
||||||
SLAB_PANIC, NULL);
|
|
||||||
}
|
}
|
||||||
|
|
||||||
/*
|
/*
|
||||||
|
@ -486,27 +481,24 @@ static noinline void validate_nommu_regions(void)
|
||||||
return;
|
return;
|
||||||
|
|
||||||
last = rb_entry(lastp, struct vm_region, vm_rb);
|
last = rb_entry(lastp, struct vm_region, vm_rb);
|
||||||
if (unlikely(last->vm_end <= last->vm_start))
|
BUG_ON(unlikely(last->vm_end <= last->vm_start));
|
||||||
BUG();
|
BUG_ON(unlikely(last->vm_top < last->vm_end));
|
||||||
if (unlikely(last->vm_top < last->vm_end))
|
|
||||||
BUG();
|
|
||||||
|
|
||||||
while ((p = rb_next(lastp))) {
|
while ((p = rb_next(lastp))) {
|
||||||
region = rb_entry(p, struct vm_region, vm_rb);
|
region = rb_entry(p, struct vm_region, vm_rb);
|
||||||
last = rb_entry(lastp, struct vm_region, vm_rb);
|
last = rb_entry(lastp, struct vm_region, vm_rb);
|
||||||
|
|
||||||
if (unlikely(region->vm_end <= region->vm_start))
|
BUG_ON(unlikely(region->vm_end <= region->vm_start));
|
||||||
BUG();
|
BUG_ON(unlikely(region->vm_top < region->vm_end));
|
||||||
if (unlikely(region->vm_top < region->vm_end))
|
BUG_ON(unlikely(region->vm_start < last->vm_top));
|
||||||
BUG();
|
|
||||||
if (unlikely(region->vm_start < last->vm_top))
|
|
||||||
BUG();
|
|
||||||
|
|
||||||
lastp = p;
|
lastp = p;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
#else
|
#else
|
||||||
#define validate_nommu_regions() do {} while(0)
|
static void validate_nommu_regions(void)
|
||||||
|
{
|
||||||
|
}
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
/*
|
/*
|
||||||
|
@ -563,16 +555,17 @@ static void free_page_series(unsigned long from, unsigned long to)
|
||||||
struct page *page = virt_to_page(from);
|
struct page *page = virt_to_page(from);
|
||||||
|
|
||||||
kdebug("- free %lx", from);
|
kdebug("- free %lx", from);
|
||||||
atomic_dec(&mmap_pages_allocated);
|
atomic_long_dec(&mmap_pages_allocated);
|
||||||
if (page_count(page) != 1)
|
if (page_count(page) != 1)
|
||||||
kdebug("free page %p [%d]", page, page_count(page));
|
kdebug("free page %p: refcount not one: %d",
|
||||||
|
page, page_count(page));
|
||||||
put_page(page);
|
put_page(page);
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* release a reference to a region
|
* release a reference to a region
|
||||||
* - the caller must hold the region semaphore, which this releases
|
* - the caller must hold the region semaphore for writing, which this releases
|
||||||
* - the region may not have been added to the tree yet, in which case vm_top
|
* - the region may not have been added to the tree yet, in which case vm_top
|
||||||
* will equal vm_start
|
* will equal vm_start
|
||||||
*/
|
*/
|
||||||
|
@ -1096,7 +1089,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
|
||||||
goto enomem;
|
goto enomem;
|
||||||
|
|
||||||
total = 1 << order;
|
total = 1 << order;
|
||||||
atomic_add(total, &mmap_pages_allocated);
|
atomic_long_add(total, &mmap_pages_allocated);
|
||||||
|
|
||||||
point = rlen >> PAGE_SHIFT;
|
point = rlen >> PAGE_SHIFT;
|
||||||
|
|
||||||
|
@ -1107,7 +1100,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
|
||||||
order = ilog2(total - point);
|
order = ilog2(total - point);
|
||||||
n = 1 << order;
|
n = 1 << order;
|
||||||
kdebug("shave %lu/%lu @%lu", n, total - point, total);
|
kdebug("shave %lu/%lu @%lu", n, total - point, total);
|
||||||
atomic_sub(n, &mmap_pages_allocated);
|
atomic_long_sub(n, &mmap_pages_allocated);
|
||||||
total -= n;
|
total -= n;
|
||||||
set_page_refcounted(pages + total);
|
set_page_refcounted(pages + total);
|
||||||
__free_pages(pages + total, order);
|
__free_pages(pages + total, order);
|
||||||
|
@ -1536,10 +1529,15 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
|
||||||
/* find the first potentially overlapping VMA */
|
/* find the first potentially overlapping VMA */
|
||||||
vma = find_vma(mm, start);
|
vma = find_vma(mm, start);
|
||||||
if (!vma) {
|
if (!vma) {
|
||||||
printk(KERN_WARNING
|
static int limit = 0;
|
||||||
"munmap of memory not mmapped by process %d (%s):"
|
if (limit < 5) {
|
||||||
" 0x%lx-0x%lx\n",
|
printk(KERN_WARNING
|
||||||
current->pid, current->comm, start, start + len - 1);
|
"munmap of memory not mmapped by process %d"
|
||||||
|
" (%s): 0x%lx-0x%lx\n",
|
||||||
|
current->pid, current->comm,
|
||||||
|
start, start + len - 1);
|
||||||
|
limit++;
|
||||||
|
}
|
||||||
return -EINVAL;
|
return -EINVAL;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue
Block a user