Merge branch 'master' into next

[linux-2.6-omap-h63xx.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index d3fa10a726cf7446a47a9aebd4db0d1a87b4cca2..3b3ed0bb9fdb21e9bd7819367ca2603e6133a1d4 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -20,6 +20,7 @@
 #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>
@@ -658,6 +659,9 @@ again:                      remove_next = 1 + (end > next->vm_end);
        validate_mm(mm);
 }
 
+/* Flags that can be inherited from an existing mapping when merging */
+#define VM_MERGEABLE_FLAGS (VM_CAN_NONLINEAR)
+
 /*
  * If the vma has a ->close operation then the driver probably needs to release
  * per-vma resources, so we don't attempt to merge those.
@@ -665,7 +669,7 @@ again:                      remove_next = 1 + (end > next->vm_end);
 static inline int is_mergeable_vma(struct vm_area_struct *vma,
                        struct file *file, unsigned long vm_flags)
 {
-       if (vma->vm_flags != vm_flags)
+       if ((vma->vm_flags ^ vm_flags) & ~VM_MERGEABLE_FLAGS)
                return 0;
        if (vma->vm_file != file)
                return 0;
@@ -1047,6 +1051,9 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
        }
 
        error = security_file_mmap(file, reqprot, prot, flags, addr, 0);
+       if (error)
+               return error;
+       error = ima_file_mmap(file, prot);
        if (error)
                return error;
 
@@ -1087,6 +1094,15 @@ int vma_wants_writenotify(struct vm_area_struct *vma)
                mapping_cap_account_dirty(vma->vm_file->f_mapping);
 }
 
+/*
+ * We account for memory if it's a private writeable mapping,
+ * and VM_NORESERVE wasn't set.
+ */
+static inline int accountable_mapping(unsigned int vm_flags)
+{
+       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,
@@ -1114,23 +1130,24 @@ munmap_back:
        if (!may_expand_vm(mm, len >> PAGE_SHIFT))
                return -ENOMEM;
 
-       if (flags & MAP_NORESERVE)
+       /*
+        * Set 'VM_NORESERVE' if we should not account for the
+        * memory use of this mapping. We only honor MAP_NORESERVE
+        * if we're allowed to overcommit memory.
+        */
+       if ((flags & MAP_NORESERVE) && sysctl_overcommit_memory != OVERCOMMIT_NEVER)
+               vm_flags |= VM_NORESERVE;
+       if (!accountable)
                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;
-               }
+       /*
+        * Private writable mapping: check memory availability
+        */
+       if (accountable_mapping(vm_flags)) {
+               charged = len >> PAGE_SHIFT;
+               if (security_vm_enough_memory(charged))
+                       return -ENOMEM;
+               vm_flags |= VM_ACCOUNT;
        }
 
        /*
@@ -1181,14 +1198,6 @@ munmap_back:
                        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