#include <linux/fs.h>
#include <linux/personality.h>
#include <linux/security.h>
+#include <linux/ima.h>
#include <linux/hugetlb.h>
#include <linux/profile.h>
#include <linux/module.h>
int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
int sysctl_overcommit_ratio = 50; /* default is 50% */
int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;
-atomic_long_t vm_committed_space = ATOMIC_LONG_INIT(0);
+struct percpu_counter vm_committed_as;
/*
* Check that a process has enough memory to allocate a new virtual
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);
struct inode *inode;
unsigned int vm_flags;
int error;
- int accountable = 1;
unsigned long reqprot = prot;
/*
return -EPERM;
vm_flags &= ~VM_MAYEXEC;
}
- if (is_file_hugepages(file))
- accountable = 0;
if (!file->f_op || !file->f_op->mmap)
return -ENODEV;
error = security_file_mmap(file, reqprot, prot, flags, addr, 0);
if (error)
return error;
+ error = ima_file_mmap(file, prot);
+ if (error)
+ return error;
- return mmap_region(file, addr, len, flags, vm_flags, pgoff,
- accountable);
+ return mmap_region(file, addr, len, flags, vm_flags, pgoff);
}
EXPORT_SYMBOL(do_mmap_pgoff);
mapping_cap_account_dirty(vma->vm_file->f_mapping);
}
+/*
+ * We account for memory if it's a private writeable mapping,
+ * not hugepages and VM_NORESERVE wasn't set.
+ */
+static inline int accountable_mapping(struct file *file, unsigned int vm_flags)
+{
+ /*
+ * hugetlb has its own accounting separate from the core VM
+ * VM_HUGETLB may not be set yet so we cannot check for that flag.
+ */
+ if (file && is_file_hugepages(file))
+ return 0;
+
+ return (vm_flags & (VM_NORESERVE | VM_SHARED | VM_WRITE)) == VM_WRITE;
+}
+
unsigned long mmap_region(struct file *file, unsigned long addr,
unsigned long len, unsigned long flags,
- unsigned int vm_flags, unsigned long pgoff,
- int accountable)
+ unsigned int vm_flags, unsigned long pgoff)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma, *prev;
if (!may_expand_vm(mm, len >> PAGE_SHIFT))
return -ENOMEM;
- if (flags & MAP_NORESERVE)
- vm_flags |= VM_NORESERVE;
+ /*
+ * Set 'VM_NORESERVE' if we should not account for the
+ * memory use of this mapping.
+ */
+ if ((flags & MAP_NORESERVE)) {
+ /* We honor MAP_NORESERVE if allowed to overcommit */
+ if (sysctl_overcommit_memory != OVERCOMMIT_NEVER)
+ vm_flags |= VM_NORESERVE;
- if (accountable && (!(flags & MAP_NORESERVE) ||
- sysctl_overcommit_memory == OVERCOMMIT_NEVER)) {
- if (vm_flags & VM_SHARED) {
- /* Check memory availability in shmem_file_setup? */
- vm_flags |= VM_ACCOUNT;
- } else if (vm_flags & VM_WRITE) {
- /*
- * Private writable mapping: check memory availability
- */
- charged = len >> PAGE_SHIFT;
- if (security_vm_enough_memory(charged))
- return -ENOMEM;
- vm_flags |= VM_ACCOUNT;
- }
+ /* hugetlb applies strict overcommit unless MAP_NORESERVE */
+ if (file && is_file_hugepages(file))
+ vm_flags |= VM_NORESERVE;
+ }
+
+ /*
+ * Private writable mapping: check memory availability
+ */
+ if (accountable_mapping(file, vm_flags)) {
+ charged = len >> PAGE_SHIFT;
+ if (security_vm_enough_memory(charged))
+ return -ENOMEM;
+ vm_flags |= VM_ACCOUNT;
}
/*
goto free_vma;
}
- /* We set VM_ACCOUNT in a shared mapping's vm_flags, to inform
- * shmem_zero_setup (perhaps called through /dev/zero's ->mmap)
- * that memory reservation must be checked; but that reservation
- * belongs to shared memory object, not to vma: so now clear it.
- */
- if ((vm_flags & (VM_SHARED|VM_ACCOUNT)) == (VM_SHARED|VM_ACCOUNT))
- vma->vm_flags &= ~VM_ACCOUNT;
-
/* Can addr have changed??
*
* Answer: Yes, several device drivers can do it in their
* Overcommit.. This must be the final test, as it will
* update security statistics.
*/
- if (security_vm_enough_memory(grow))
+ if (security_vm_enough_memory_mm(mm, grow))
return -ENOMEM;
/* Ok, everything looks good - let it rip */
unsigned long end;
/* mm's last user has gone, and its about to be pulled down */
- arch_exit_mmap(mm);
mmu_notifier_release(mm);
- if (!mm->mmap) /* Can happen if dup_mmap() received an OOM */
- return;
-
if (mm->locked_vm) {
vma = mm->mmap;
while (vma) {
vma = vma->vm_next;
}
}
+
+ arch_exit_mmap(mm);
+
vma = mm->mmap;
+ if (!vma) /* Can happen if dup_mmap() received an OOM */
+ return;
+
lru_add_drain();
flush_cache_mm(mm);
tlb = tlb_gather_mmu(mm, 1);
*/
void __init mmap_init(void)
{
- 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);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff