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authorJames Morris <jmorris@namei.org>2009-02-06 11:01:45 +1100
committerJames Morris <jmorris@namei.org>2009-02-06 11:01:45 +1100
commitcb5629b10d64a8006622ce3a52bc887d91057d69 (patch)
tree7c06d8f30783115e3384721046258ce615b129c5 /mm/mmap.c
parent8920d5ad6ba74ae8ab020e90cc4d976980e68701 (diff)
parentf01d1d546abb2f4028b5299092f529eefb01253a (diff)
downloadlinux-cb5629b10d64a8006622ce3a52bc887d91057d69.tar.gz
Merge branch 'master' into next
Conflicts:
	fs/namei.c

Manually merged per:

diff --cc fs/namei.c
index 734f2b5,bbc15c2..0000000
--- a/fs/namei.c
+++ b/fs/namei.c
@@@ -860,9 -848,8 +849,10 @@@ static int __link_path_walk(const char
  		nd->flags |= LOOKUP_CONTINUE;
  		err = exec_permission_lite(inode);
  		if (err == -EAGAIN)
- 			err = vfs_permission(nd, MAY_EXEC);
+ 			err = inode_permission(nd->path.dentry->d_inode,
+ 					       MAY_EXEC);
 +		if (!err)
 +			err = ima_path_check(&nd->path, MAY_EXEC);
   		if (err)
  			break;

@@@ -1525,14 -1506,9 +1509,14 @@@ int may_open(struct path *path, int acc
  		flag &= ~O_TRUNC;
  	}

- 	error = vfs_permission(nd, acc_mode);
+ 	error = inode_permission(inode, acc_mode);
  	if (error)
  		return error;
 +
- 	error = ima_path_check(&nd->path,
++	error = ima_path_check(path,
 +			       acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC));
 +	if (error)
 +		return error;
  	/*
  	 * An append-only file must be opened in append mode for writing.
  	 */

Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'mm/mmap.c')
-rw-r--r--mm/mmap.c117
1 files changed, 60 insertions, 57 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index c3647f3b0621..3b3ed0bb9fdb 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3,7 +3,7 @@
  *
  * Written by obz.
  *
- * Address space accounting code	<alan@redhat.com>
+ * Address space accounting code	<alan@lxorguk.ukuu.org.uk>
  */
 
 #include <linux/slab.h>
@@ -246,7 +246,7 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
 	return next;
 }
 
-asmlinkage unsigned long sys_brk(unsigned long brk)
+SYSCALL_DEFINE1(brk, unsigned long, brk)
 {
 	unsigned long rlim, retval;
 	unsigned long newbrk, oldbrk;
@@ -414,7 +414,7 @@ void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma,
 
 static void __vma_link_file(struct vm_area_struct *vma)
 {
-	struct file * file;
+	struct file *file;
 
 	file = vma->vm_file;
 	if (file) {
@@ -475,11 +475,10 @@ static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
  * insert vm structure into list and rbtree and anon_vma,
  * but it has already been inserted into prio_tree earlier.
  */
-static void
-__insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
+static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
 {
-	struct vm_area_struct * __vma, * prev;
-	struct rb_node ** rb_link, * rb_parent;
+	struct vm_area_struct *__vma, *prev;
+	struct rb_node **rb_link, *rb_parent;
 
 	__vma = find_vma_prepare(mm, vma->vm_start,&prev, &rb_link, &rb_parent);
 	BUG_ON(__vma && __vma->vm_start < vma->vm_end);
@@ -660,6 +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.
@@ -667,7 +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;
@@ -909,7 +911,7 @@ void vm_stat_account(struct mm_struct *mm, unsigned long flags,
  * The caller must hold down_write(current->mm->mmap_sem).
  */
 
-unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
+unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 			unsigned long len, unsigned long prot,
 			unsigned long flags, unsigned long pgoff)
 {
@@ -1092,6 +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,
@@ -1119,36 +1130,32 @@ 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;
 	}
 
 	/*
-	 * Can we just expand an old private anonymous mapping?
-	 * The VM_SHARED test is necessary because shmem_zero_setup
-	 * will create the file object for a shared anonymous map below.
+	 * Can we just expand an old mapping?
 	 */
-	if (!file && !(vm_flags & VM_SHARED)) {
-		vma = vma_merge(mm, prev, addr, addr + len, vm_flags,
-					NULL, NULL, pgoff, NULL);
-		if (vma)
-			goto out;
-	}
+	vma = vma_merge(mm, prev, addr, addr + len, vm_flags, NULL, file, pgoff, NULL);
+	if (vma)
+		goto out;
 
 	/*
 	 * Determine the object being mapped and call the appropriate
@@ -1191,14 +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
@@ -1211,17 +1210,8 @@ munmap_back:
 	if (vma_wants_writenotify(vma))
 		vma->vm_page_prot = vm_get_page_prot(vm_flags & ~VM_SHARED);
 
-	if (file && vma_merge(mm, prev, addr, vma->vm_end,
-			vma->vm_flags, NULL, file, pgoff, vma_policy(vma))) {
-		mpol_put(vma_policy(vma));
-		kmem_cache_free(vm_area_cachep, vma);
-		fput(file);
-		if (vm_flags & VM_EXECUTABLE)
-			removed_exe_file_vma(mm);
-	} else {
-		vma_link(mm, vma, prev, rb_link, rb_parent);
-		file = vma->vm_file;
-	}
+	vma_link(mm, vma, prev, rb_link, rb_parent);
+	file = vma->vm_file;
 
 	/* Once vma denies write, undo our temporary denial count */
 	if (correct_wcount)
@@ -1468,7 +1458,7 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
 EXPORT_SYMBOL(get_unmapped_area);
 
 /* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
-struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr)
+struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
 {
 	struct vm_area_struct *vma = NULL;
 
@@ -1511,7 +1501,7 @@ find_vma_prev(struct mm_struct *mm, unsigned long addr,
 			struct vm_area_struct **pprev)
 {
 	struct vm_area_struct *vma = NULL, *prev = NULL;
-	struct rb_node * rb_node;
+	struct rb_node *rb_node;
 	if (!mm)
 		goto out;
 
@@ -1545,7 +1535,7 @@ out:
  * update accounting. This is shared with both the
  * grow-up and grow-down cases.
  */
-static int acct_stack_growth(struct vm_area_struct * vma, unsigned long size, unsigned long grow)
+static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, unsigned long grow)
 {
 	struct mm_struct *mm = vma->vm_mm;
 	struct rlimit *rlim = current->signal->rlim;
@@ -1953,7 +1943,7 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
 
 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;
@@ -2095,6 +2085,9 @@ void exit_mmap(struct mm_struct *mm)
 	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) {
@@ -2107,7 +2100,7 @@ void exit_mmap(struct mm_struct *mm)
 	lru_add_drain();
 	flush_cache_mm(mm);
 	tlb = tlb_gather_mmu(mm, 1);
-	/* Don't update_hiwater_rss(mm) here, do_exit already did */
+	/* update_hiwater_rss(mm) here? but nobody should be looking */
 	/* Use -1 here to ensure all VMAs in the mm are unmapped */
 	end = unmap_vmas(&tlb, vma, 0, -1, &nr_accounted, NULL);
 	vm_unacct_memory(nr_accounted);
@@ -2474,3 +2467,13 @@ void mm_drop_all_locks(struct mm_struct *mm)
 
 	mutex_unlock(&mm_all_locks_mutex);
 }
+
+/*
+ * initialise the VMA slab
+ */
+void __init mmap_init(void)
+{
+	vm_area_cachep = kmem_cache_create("vm_area_struct",
+			sizeof(struct vm_area_struct), 0,
+			SLAB_PANIC, NULL);
+}