* Copyright (c) 2000-2003 David McCullough <davidm@snapgear.com>
* Copyright (c) 2000-2001 D Jeff Dionne <jeff@uClinux.org>
* Copyright (c) 2002 Greg Ungerer <gerg@snapgear.com>
- * Copyright (c) 2007 Paul Mundt <lethal@linux-sh.org>
+ * Copyright (c) 2007-2009 Paul Mundt <lethal@linux-sh.org>
*/
#include <linux/module.h>
struct page *mem_map;
unsigned long max_mapnr;
unsigned long num_physpages;
-atomic_long_t vm_committed_space = ATOMIC_LONG_INIT(0);
+struct percpu_counter vm_committed_as;
int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
int sysctl_overcommit_ratio = 50; /* default is 50% */
int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
+int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS;
int heap_stack_gap = 0;
-atomic_t mmap_pages_allocated;
+/* amount of vm to protect from userspace access */
+unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
+
+atomic_long_t mmap_pages_allocated;
EXPORT_SYMBOL(mem_map);
EXPORT_SYMBOL(num_physpages);
return ksize(objp);
/*
+ * If it's not a compound page, see if we have a matching VMA
+ * region. This test is intentionally done in reverse order,
+ * so if there's no VMA, we still fall through and hand back
+ * PAGE_SIZE for 0-order pages.
+ */
+ if (!PageCompound(page)) {
+ struct vm_area_struct *vma;
+
+ vma = find_vma(current->mm, (unsigned long)objp);
+ if (vma)
+ return vma->vm_end - vma->vm_start;
+ }
+
+ /*
* The ksize() function is only guaranteed to work for pointers
* returned by kmalloc(). So handle arbitrary pointers here.
*/
}
EXPORT_SYMBOL(vunmap);
+void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
+{
+ BUG();
+ return NULL;
+}
+EXPORT_SYMBOL(vm_map_ram);
+
+void vm_unmap_ram(const void *mem, unsigned int count)
+{
+ BUG();
+}
+EXPORT_SYMBOL(vm_unmap_ram);
+
+void vm_unmap_aliases(void)
+{
+}
+EXPORT_SYMBOL_GPL(vm_unmap_aliases);
+
/*
* Implement a stub for vmalloc_sync_all() if the architecture chose not to
* have one.
* to a regular file. in this case, the unmapping will need
* to invoke file system routines that need the global lock.
*/
-asmlinkage unsigned long sys_brk(unsigned long brk)
+SYSCALL_DEFINE1(brk, unsigned long, brk)
{
struct mm_struct *mm = current->mm;
*/
void __init mmap_init(void)
{
- vm_region_jar = kmem_cache_create("vm_region_jar",
- 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);
+ int ret;
+
+ ret = percpu_counter_init(&vm_committed_as, 0);
+ VM_BUG_ON(ret);
+ vm_region_jar = KMEM_CACHE(vm_region, SLAB_PANIC);
}
/*
return;
last = rb_entry(lastp, struct vm_region, vm_rb);
- if (unlikely(last->vm_end <= last->vm_start))
- BUG();
+ BUG_ON(unlikely(last->vm_end <= last->vm_start));
+ BUG_ON(unlikely(last->vm_top < last->vm_end));
while ((p = rb_next(lastp))) {
region = rb_entry(p, struct vm_region, vm_rb);
last = rb_entry(lastp, struct vm_region, vm_rb);
- if (unlikely(region->vm_end <= region->vm_start))
- BUG();
- if (unlikely(region->vm_start < last->vm_end))
- BUG();
+ BUG_ON(unlikely(region->vm_end <= region->vm_start));
+ BUG_ON(unlikely(region->vm_top < region->vm_end));
+ BUG_ON(unlikely(region->vm_start < last->vm_top));
lastp = p;
}
}
#else
-#define validate_nommu_regions() do {} while(0)
+static void validate_nommu_regions(void)
+{
+}
#endif
/*
validate_nommu_regions();
- BUG_ON(region->vm_start & ~PAGE_MASK);
-
parent = NULL;
p = &nommu_region_tree.rb_node;
while (*p) {
struct page *page = virt_to_page(from);
kdebug("- free %lx", from);
- atomic_dec(&mmap_pages_allocated);
+ atomic_long_dec(&mmap_pages_allocated);
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);
}
}
/*
* release a reference to a region
- * - the caller must hold the region semaphore, which this releases
- * - the region may not have been added to the tree yet, in which case vm_end
+ * - 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
* will equal vm_start
*/
static void __put_nommu_region(struct vm_region *region)
BUG_ON(!nommu_region_tree.rb_node);
if (atomic_dec_and_test(®ion->vm_usage)) {
- if (region->vm_end > region->vm_start)
+ if (region->vm_top > region->vm_start)
delete_nommu_region(region);
up_write(&nommu_region_sem);
* from ramfs/tmpfs mustn't be released here */
if (region->vm_flags & VM_MAPPED_COPY) {
kdebug("free series");
- free_page_series(region->vm_start, region->vm_end);
+ free_page_series(region->vm_start, region->vm_top);
}
kmem_cache_free(vm_region_jar, region);
} else {
int ret;
ret = vma->vm_file->f_op->mmap(vma->vm_file, vma);
+ if (ret == 0) {
+ vma->vm_region->vm_top = vma->vm_region->vm_end;
+ return ret;
+ }
if (ret != -ENOSYS)
return ret;
*/
if (vma->vm_file) {
ret = vma->vm_file->f_op->mmap(vma->vm_file, vma);
- if (ret != -ENOSYS) {
+ if (ret == 0) {
/* shouldn't return success if we're not sharing */
- BUG_ON(ret == 0 && !(vma->vm_flags & VM_MAYSHARE));
- return ret; /* success or a real error */
+ BUG_ON(!(vma->vm_flags & VM_MAYSHARE));
+ vma->vm_region->vm_top = vma->vm_region->vm_end;
+ return ret;
}
+ if (ret != -ENOSYS)
+ return ret;
/* getting an ENOSYS error indicates that direct mmap isn't
* possible (as opposed to tried but failed) so we'll try to
if (!pages)
goto enomem;
- /* we allocated a power-of-2 sized page set, so we need to trim off the
- * excess */
total = 1 << order;
- atomic_add(total, &mmap_pages_allocated);
+ atomic_long_add(total, &mmap_pages_allocated);
point = rlen >> PAGE_SHIFT;
- while (total > point) {
- order = ilog2(total - point);
- n = 1 << order;
- kdebug("shave %lu/%lu @%lu", n, total - point, total);
- atomic_sub(n, &mmap_pages_allocated);
- total -= n;
- set_page_refcounted(pages + total);
- __free_pages(pages + total, order);
+
+ /* we allocated a power-of-2 sized page set, so we may want to trim off
+ * the excess */
+ if (sysctl_nr_trim_pages && total - point >= sysctl_nr_trim_pages) {
+ while (total > point) {
+ order = ilog2(total - point);
+ n = 1 << order;
+ kdebug("shave %lu/%lu @%lu", n, total - point, total);
+ atomic_long_sub(n, &mmap_pages_allocated);
+ total -= n;
+ set_page_refcounted(pages + total);
+ __free_pages(pages + total, order);
+ }
}
- total = rlen >> PAGE_SHIFT;
for (point = 1; point < total; point++)
set_page_refcounted(&pages[point]);
region->vm_flags = vma->vm_flags |= VM_MAPPED_COPY;
region->vm_start = (unsigned long) base;
region->vm_end = region->vm_start + rlen;
+ region->vm_top = region->vm_start + (total << PAGE_SHIFT);
vma->vm_start = region->vm_start;
vma->vm_end = region->vm_start + len;
free_page_series(region->vm_start, region->vm_end);
region->vm_start = vma->vm_start = 0;
region->vm_end = vma->vm_end = 0;
+ region->vm_top = 0;
return ret;
enomem:
- printk("Allocation of length %lu from process %d failed\n",
- len, current->pid);
+ printk("Allocation of length %lu from process %d (%s) failed\n",
+ len, current->pid, current->comm);
show_free_areas();
return -ENOMEM;
}
npages = (addr - vma->vm_start) >> PAGE_SHIFT;
if (new_below) {
- region->vm_end = new->vm_end = addr;
+ region->vm_top = region->vm_end = new->vm_end = addr;
} else {
region->vm_start = new->vm_start = addr;
region->vm_pgoff = new->vm_pgoff += npages;
vma->vm_region->vm_pgoff = vma->vm_pgoff += npages;
} else {
vma->vm_region->vm_end = vma->vm_end = addr;
+ vma->vm_region->vm_top = addr;
}
add_nommu_region(vma->vm_region);
add_nommu_region(new->vm_region);
down_write(&nommu_region_sem);
delete_nommu_region(region);
- if (from > region->vm_start)
- region->vm_end = from;
- else
+ if (from > region->vm_start) {
+ to = region->vm_top;
+ region->vm_top = region->vm_end = from;
+ } else {
region->vm_start = to;
+ }
add_nommu_region(region);
up_write(&nommu_region_sem);
/* find the first potentially overlapping VMA */
vma = find_vma(mm, start);
if (!vma) {
- printk(KERN_WARNING
- "munmap of memory not mmapped by process %d (%s):"
- " 0x%lx-0x%lx\n",
- current->pid, current->comm, start, start + len - 1);
+ static int limit = 0;
+ if (limit < 5) {
+ printk(KERN_WARNING
+ "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;
}
}
EXPORT_SYMBOL(do_munmap);
-asmlinkage long sys_munmap(unsigned long addr, size_t len)
+SYSCALL_DEFINE2(munmap, unsigned long, addr, size_t, len)
{
int ret;
struct mm_struct *mm = current->mm;
}
EXPORT_SYMBOL(do_mremap);
-asmlinkage
-unsigned long sys_mremap(unsigned long addr,
- unsigned long old_len, unsigned long new_len,
- unsigned long flags, unsigned long new_addr)
+SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
+ unsigned long, new_len, unsigned long, flags,
+ unsigned long, new_addr)
{
unsigned long ret;
if (mm)
allowed -= mm->total_vm / 32;
- /*
- * cast `allowed' as a signed long because vm_committed_space
- * sometimes has a negative value
- */
- if (atomic_long_read(&vm_committed_space) < (long)allowed)
+ if (percpu_counter_read_positive(&vm_committed_as) < allowed)
return 0;
+
error:
vm_unacct_memory(pages);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff