1 files changed, 120 insertions, 39 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index feead1943d9..f99ff3e50bd 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -127,7 +127,7 @@ static inline struct shmem_sb_info *SHMEM_SB(struct super_block *sb)
 static inline int shmem_acct_size(unsigned long flags, loff_t size)
 {
 	return (flags & VM_NORESERVE) ?
-		0 : security_vm_enough_memory_kern(VM_ACCT(size));
+		0 : security_vm_enough_memory_mm(current->mm, VM_ACCT(size));
 }
 
 static inline void shmem_unacct_size(unsigned long flags, loff_t size)
@@ -145,7 +145,7 @@ static inline void shmem_unacct_size(unsigned long flags, loff_t size)
 static inline int shmem_acct_block(unsigned long flags)
 {
 	return (flags & VM_NORESERVE) ?
-		security_vm_enough_memory_kern(VM_ACCT(PAGE_CACHE_SIZE)) : 0;
+		security_vm_enough_memory_mm(current->mm, VM_ACCT(PAGE_CACHE_SIZE)) : 0;
 }
 
 static inline void shmem_unacct_blocks(unsigned long flags, long pages)
@@ -379,7 +379,7 @@ static int shmem_free_swap(struct address_space *mapping,
 /*
  * Pagevec may contain swap entries, so shuffle up pages before releasing.
  */
-static void shmem_pagevec_release(struct pagevec *pvec)
+static void shmem_deswap_pagevec(struct pagevec *pvec)
 {
 	int i, j;
 
@@ -389,7 +389,36 @@ static void shmem_pagevec_release(struct pagevec *pvec)
 			pvec->pages[j++] = page;
 	}
 	pvec->nr = j;
-	pagevec_release(pvec);
+}
+
+/*
+ * SysV IPC SHM_UNLOCK restore Unevictable pages to their evictable lists.
+ */
+void shmem_unlock_mapping(struct address_space *mapping)
+{
+	struct pagevec pvec;
+	pgoff_t indices[PAGEVEC_SIZE];
+	pgoff_t index = 0;
+
+	pagevec_init(&pvec, 0);
+	/*
+	 * Minor point, but we might as well stop if someone else SHM_LOCKs it.
+	 */
+	while (!mapping_unevictable(mapping)) {
+		/*
+		 * Avoid pagevec_lookup(): find_get_pages() returns 0 as if it
+		 * has finished, if it hits a row of PAGEVEC_SIZE swap entries.
+		 */
+		pvec.nr = shmem_find_get_pages_and_swap(mapping, index,
+					PAGEVEC_SIZE, pvec.pages, indices);
+		if (!pvec.nr)
+			break;
+		index = indices[pvec.nr - 1] + 1;
+		shmem_deswap_pagevec(&pvec);
+		check_move_unevictable_pages(pvec.pages, pvec.nr);
+		pagevec_release(&pvec);
+		cond_resched();
+	}
 }
 
 /*
@@ -440,7 +469,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
 			}
 			unlock_page(page);
 		}
-		shmem_pagevec_release(&pvec);
+		shmem_deswap_pagevec(&pvec);
+		pagevec_release(&pvec);
 		mem_cgroup_uncharge_end();
 		cond_resched();
 		index++;
@@ -470,7 +500,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
 			continue;
 		}
 		if (index == start && indices[0] > end) {
-			shmem_pagevec_release(&pvec);
+			shmem_deswap_pagevec(&pvec);
+			pagevec_release(&pvec);
 			break;
 		}
 		mem_cgroup_uncharge_start();
@@ -494,7 +525,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
 			}
 			unlock_page(page);
 		}
-		shmem_pagevec_release(&pvec);
+		shmem_deswap_pagevec(&pvec);
+		pagevec_release(&pvec);
 		mem_cgroup_uncharge_end();
 		index++;
 	}
@@ -1068,13 +1100,6 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
 		user_shm_unlock(inode->i_size, user);
 		info->flags &= ~VM_LOCKED;
 		mapping_clear_unevictable(file->f_mapping);
-		/*
-		 * Ensure that a racing putback_lru_page() can see
-		 * the pages of this mapping are evictable when we
-		 * skip them due to !PageLRU during the scan.
-		 */
-		smp_mb__after_clear_bit();
-		scan_mapping_unevictable_pages(file->f_mapping);
 	}
 	retval = 0;
 
@@ -1153,6 +1178,12 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
 static const struct inode_operations shmem_symlink_inode_operations;
 static const struct inode_operations shmem_short_symlink_operations;
 
+#ifdef CONFIG_TMPFS_XATTR
+static int shmem_initxattrs(struct inode *, const struct xattr *, void *);
+#else
+#define shmem_initxattrs NULL
+#endif
+
 static int
 shmem_write_begin(struct file *file, struct address_space *mapping,
 			loff_t pos, unsigned len, unsigned flags,
@@ -1465,7 +1496,7 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
 	if (inode) {
 		error = security_inode_init_security(inode, dir,
 						     &dentry->d_name,
-						     NULL, NULL);
+						     shmem_initxattrs, NULL);
 		if (error) {
 			if (error != -EOPNOTSUPP) {
 				iput(inode);
@@ -1605,7 +1636,7 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 		return -ENOSPC;
 
 	error = security_inode_init_security(inode, dir, &dentry->d_name,
-					     NULL, NULL);
+					     shmem_initxattrs, NULL);
 	if (error) {
 		if (error != -EOPNOTSUPP) {
 			iput(inode);
@@ -1631,9 +1662,9 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 		}
 		inode->i_mapping->a_ops = &shmem_aops;
 		inode->i_op = &shmem_symlink_inode_operations;
-		kaddr = kmap_atomic(page, KM_USER0);
+		kaddr = kmap_atomic(page);
 		memcpy(kaddr, symname, len);
-		kunmap_atomic(kaddr, KM_USER0);
+		kunmap_atomic(kaddr);
 		set_page_dirty(page);
 		unlock_page(page);
 		page_cache_release(page);
@@ -1679,6 +1710,66 @@ static void shmem_put_link(struct dentry *dentry, struct nameidata *nd, void *co
  * filesystem level, though.
  */
 
+/*
+ * Allocate new xattr and copy in the value; but leave the name to callers.
+ */
+static struct shmem_xattr *shmem_xattr_alloc(const void *value, size_t size)
+{
+	struct shmem_xattr *new_xattr;
+	size_t len;
+
+	/* wrap around? */
+	len = sizeof(*new_xattr) + size;
+	if (len <= sizeof(*new_xattr))
+		return NULL;
+
+	new_xattr = kmalloc(len, GFP_KERNEL);
+	if (!new_xattr)
+		return NULL;
+
+	new_xattr->size = size;
+	memcpy(new_xattr->value, value, size);
+	return new_xattr;
+}
+
+/*
+ * Callback for security_inode_init_security() for acquiring xattrs.
+ */
+static int shmem_initxattrs(struct inode *inode,
+			    const struct xattr *xattr_array,
+			    void *fs_info)
+{
+	struct shmem_inode_info *info = SHMEM_I(inode);
+	const struct xattr *xattr;
+	struct shmem_xattr *new_xattr;
+	size_t len;
+
+	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+		new_xattr = shmem_xattr_alloc(xattr->value, xattr->value_len);
+		if (!new_xattr)
+			return -ENOMEM;
+
+		len = strlen(xattr->name) + 1;
+		new_xattr->name = kmalloc(XATTR_SECURITY_PREFIX_LEN + len,
+					  GFP_KERNEL);
+		if (!new_xattr->name) {
+			kfree(new_xattr);
+			return -ENOMEM;
+		}
+
+		memcpy(new_xattr->name, XATTR_SECURITY_PREFIX,
+		       XATTR_SECURITY_PREFIX_LEN);
+		memcpy(new_xattr->name + XATTR_SECURITY_PREFIX_LEN,
+		       xattr->name, len);
+
+		spin_lock(&info->lock);
+		list_add(&new_xattr->list, &info->xattr_list);
+		spin_unlock(&info->lock);
+	}
+
+	return 0;
+}
+
 static int shmem_xattr_get(struct dentry *dentry, const char *name,
 			   void *buffer, size_t size)
 {
@@ -1706,24 +1797,17 @@ static int shmem_xattr_get(struct dentry *dentry, const char *name,
 	return ret;
 }
 
-static int shmem_xattr_set(struct dentry *dentry, const char *name,
+static int shmem_xattr_set(struct inode *inode, const char *name,
 			   const void *value, size_t size, int flags)
 {
-	struct inode *inode = dentry->d_inode;
 	struct shmem_inode_info *info = SHMEM_I(inode);
 	struct shmem_xattr *xattr;
 	struct shmem_xattr *new_xattr = NULL;
-	size_t len;
 	int err = 0;
 
 	/* value == NULL means remove */
 	if (value) {
-		/* wrap around? */
-		len = sizeof(*new_xattr) + size;
-		if (len <= sizeof(*new_xattr))
-			return -ENOMEM;
-
-		new_xattr = kmalloc(len, GFP_KERNEL);
+		new_xattr = shmem_xattr_alloc(value, size);
 		if (!new_xattr)
 			return -ENOMEM;
 
@@ -1732,9 +1816,6 @@ static int shmem_xattr_set(struct dentry *dentry, const char *name,
 			kfree(new_xattr);
 			return -ENOMEM;
 		}
-
-		new_xattr->size = size;
-		memcpy(new_xattr->value, value, size);
 	}
 
 	spin_lock(&info->lock);
@@ -1833,7 +1914,7 @@ static int shmem_setxattr(struct dentry *dentry, const char *name,
 	if (size == 0)
 		value = "";  /* empty EA, do not remove */
 
-	return shmem_xattr_set(dentry, name, value, size, flags);
+	return shmem_xattr_set(dentry->d_inode, name, value, size, flags);
 
 }
 
@@ -1853,7 +1934,7 @@ static int shmem_removexattr(struct dentry *dentry, const char *name)
 	if (err)
 		return err;
 
-	return shmem_xattr_set(dentry, name, NULL, 0, XATTR_REPLACE);
+	return shmem_xattr_set(dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
 }
 
 static bool xattr_is_trusted(const char *name)
@@ -2150,7 +2231,6 @@ static void shmem_put_super(struct super_block *sb)
 int shmem_fill_super(struct super_block *sb, void *data, int silent)
 {
 	struct inode *inode;
-	struct dentry *root;
 	struct shmem_sb_info *sbinfo;
 	int err = -ENOMEM;
 
@@ -2207,14 +2287,11 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
 		goto failed;
 	inode->i_uid = sbinfo->uid;
 	inode->i_gid = sbinfo->gid;
-	root = d_alloc_root(inode);
-	if (!root)
-		goto failed_iput;
-	sb->s_root = root;
+	sb->s_root = d_make_root(inode);
+	if (!sb->s_root)
+		goto failed;
 	return 0;
 
-failed_iput:
-	iput(inode);
 failed:
 	shmem_put_super(sb);
 	return err;
@@ -2445,6 +2522,10 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
 	return 0;
 }
 
+void shmem_unlock_mapping(struct address_space *mapping)
+{
+}
+
 void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
 {
 	truncate_inode_pages_range(inode->i_mapping, lstart, lend);