1 files changed, 67 insertions, 51 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index 07a1d22807be..1907688b75ee 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -338,7 +338,7 @@ static int shmem_radix_tree_replace(struct address_space *mapping,
 	if (item != expected)
 		return -ENOENT;
 	__radix_tree_replace(&mapping->page_tree, node, pslot,
-			     replacement, NULL, NULL);
+			     replacement, NULL);
 	return 0;
 }
 
@@ -747,7 +747,7 @@ void shmem_unlock_mapping(struct address_space *mapping)
 	pgoff_t indices[PAGEVEC_SIZE];
 	pgoff_t index = 0;
 
-	pagevec_init(&pvec, 0);
+	pagevec_init(&pvec);
 	/*
 	 * Minor point, but we might as well stop if someone else SHM_LOCKs it.
 	 */
@@ -790,7 +790,7 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend,
 	if (lend == -1)
 		end = -1;	/* unsigned, so actually very big */
 
-	pagevec_init(&pvec, 0);
+	pagevec_init(&pvec);
 	index = start;
 	while (index < end) {
 		pvec.nr = find_get_entries(mapping, index,
@@ -2528,7 +2528,7 @@ static pgoff_t shmem_seek_hole_data(struct address_space *mapping,
 	bool done = false;
 	int i;
 
-	pagevec_init(&pvec, 0);
+	pagevec_init(&pvec);
 	pvec.nr = 1;		/* start small: we may be there already */
 	while (!done) {
 		pvec.nr = find_get_entries(mapping, index,
@@ -2717,15 +2717,28 @@ continue_resched:
 	return error;
 }
 
+static unsigned int *memfd_file_seals_ptr(struct file *file)
+{
+	if (file->f_op == &shmem_file_operations)
+		return &SHMEM_I(file_inode(file))->seals;
+
+#ifdef CONFIG_HUGETLBFS
+	if (file->f_op == &hugetlbfs_file_operations)
+		return &HUGETLBFS_I(file_inode(file))->seals;
+#endif
+
+	return NULL;
+}
+
 #define F_ALL_SEALS (F_SEAL_SEAL | \
 		     F_SEAL_SHRINK | \
 		     F_SEAL_GROW | \
 		     F_SEAL_WRITE)
 
-int shmem_add_seals(struct file *file, unsigned int seals)
+static int memfd_add_seals(struct file *file, unsigned int seals)
 {
 	struct inode *inode = file_inode(file);
-	struct shmem_inode_info *info = SHMEM_I(inode);
+	unsigned int *file_seals;
 	int error;
 
 	/*
@@ -2758,8 +2771,6 @@ int shmem_add_seals(struct file *file, unsigned int seals)
 	 * other file types.
 	 */
 
-	if (file->f_op != &shmem_file_operations)
-		return -EINVAL;
 	if (!(file->f_mode & FMODE_WRITE))
 		return -EPERM;
 	if (seals & ~(unsigned int)F_ALL_SEALS)
@@ -2767,12 +2778,18 @@ int shmem_add_seals(struct file *file, unsigned int seals)
 
 	inode_lock(inode);
 
-	if (info->seals & F_SEAL_SEAL) {
+	file_seals = memfd_file_seals_ptr(file);
+	if (!file_seals) {
+		error = -EINVAL;
+		goto unlock;
+	}
+
+	if (*file_seals & F_SEAL_SEAL) {
 		error = -EPERM;
 		goto unlock;
 	}
 
-	if ((seals & F_SEAL_WRITE) && !(info->seals & F_SEAL_WRITE)) {
+	if ((seals & F_SEAL_WRITE) && !(*file_seals & F_SEAL_WRITE)) {
 		error = mapping_deny_writable(file->f_mapping);
 		if (error)
 			goto unlock;
@@ -2784,25 +2801,22 @@ int shmem_add_seals(struct file *file, unsigned int seals)
 		}
 	}
 
-	info->seals |= seals;
+	*file_seals |= seals;
 	error = 0;
 
 unlock:
 	inode_unlock(inode);
 	return error;
 }
-EXPORT_SYMBOL_GPL(shmem_add_seals);
 
-int shmem_get_seals(struct file *file)
+static int memfd_get_seals(struct file *file)
 {
-	if (file->f_op != &shmem_file_operations)
-		return -EINVAL;
+	unsigned int *seals = memfd_file_seals_ptr(file);
 
-	return SHMEM_I(file_inode(file))->seals;
+	return seals ? *seals : -EINVAL;
 }
-EXPORT_SYMBOL_GPL(shmem_get_seals);
 
-long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
+long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	long error;
 
@@ -2812,10 +2826,10 @@ long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
 		if (arg > UINT_MAX)
 			return -EINVAL;
 
-		error = shmem_add_seals(file, arg);
+		error = memfd_add_seals(file, arg);
 		break;
 	case F_GET_SEALS:
-		error = shmem_get_seals(file);
+		error = memfd_get_seals(file);
 		break;
 	default:
 		error = -EINVAL;
@@ -3202,7 +3216,6 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 	int len;
 	struct inode *inode;
 	struct page *page;
-	struct shmem_inode_info *info;
 
 	len = strlen(symname) + 1;
 	if (len > PAGE_SIZE)
@@ -3222,7 +3235,6 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 		error = 0;
 	}
 
-	info = SHMEM_I(inode);
 	inode->i_size = len-1;
 	if (len <= SHORT_SYMLINK_LEN) {
 		inode->i_link = kmemdup(symname, len, GFP_KERNEL);
@@ -3659,7 +3671,7 @@ SYSCALL_DEFINE2(memfd_create,
 		const char __user *, uname,
 		unsigned int, flags)
 {
-	struct shmem_inode_info *info;
+	unsigned int *file_seals;
 	struct file *file;
 	int fd, error;
 	char *name;
@@ -3669,9 +3681,6 @@ SYSCALL_DEFINE2(memfd_create,
 		if (flags & ~(unsigned int)MFD_ALL_FLAGS)
 			return -EINVAL;
 	} else {
-		/* Sealing not supported in hugetlbfs (MFD_HUGETLB) */
-		if (flags & MFD_ALLOW_SEALING)
-			return -EINVAL;
 		/* Allow huge page size encoding in flags. */
 		if (flags & ~(unsigned int)(MFD_ALL_FLAGS |
 				(MFD_HUGE_MASK << MFD_HUGE_SHIFT)))
@@ -3724,12 +3733,8 @@ SYSCALL_DEFINE2(memfd_create,
 	file->f_flags |= O_RDWR | O_LARGEFILE;
 
 	if (flags & MFD_ALLOW_SEALING) {
-		/*
-		 * flags check at beginning of function ensures
-		 * this is not a hugetlbfs (MFD_HUGETLB) file.
-		 */
-		info = SHMEM_I(file_inode(file));
-		info->seals &= ~F_SEAL_SEAL;
+		file_seals = memfd_file_seals_ptr(file);
+		*file_seals &= ~F_SEAL_SEAL;
 	}
 
 	fd_install(fd, file);
@@ -3778,7 +3783,7 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
 	 * tmpfs instance, limiting inodes to one per page of lowmem;
 	 * but the internal instance is left unlimited.
 	 */
-	if (!(sb->s_flags & MS_KERNMOUNT)) {
+	if (!(sb->s_flags & SB_KERNMOUNT)) {
 		sbinfo->max_blocks = shmem_default_max_blocks();
 		sbinfo->max_inodes = shmem_default_max_inodes();
 		if (shmem_parse_options(data, sbinfo, false)) {
@@ -3786,12 +3791,12 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
 			goto failed;
 		}
 	} else {
-		sb->s_flags |= MS_NOUSER;
+		sb->s_flags |= SB_NOUSER;
 	}
 	sb->s_export_op = &shmem_export_ops;
-	sb->s_flags |= MS_NOSEC;
+	sb->s_flags |= SB_NOSEC;
 #else
-	sb->s_flags |= MS_NOUSER;
+	sb->s_flags |= SB_NOUSER;
 #endif
 
 	spin_lock_init(&sbinfo->stat_lock);
@@ -3811,7 +3816,7 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_xattr = shmem_xattr_handlers;
 #endif
 #ifdef CONFIG_TMPFS_POSIX_ACL
-	sb->s_flags |= MS_POSIXACL;
+	sb->s_flags |= SB_POSIXACL;
 #endif
 	uuid_gen(&sb->s_uuid);
 
@@ -3862,12 +3867,11 @@ static void shmem_init_inode(void *foo)
 	inode_init_once(&info->vfs_inode);
 }
 
-static int shmem_init_inodecache(void)
+static void shmem_init_inodecache(void)
 {
 	shmem_inode_cachep = kmem_cache_create("shmem_inode_cache",
 				sizeof(struct shmem_inode_info),
 				0, SLAB_PANIC|SLAB_ACCOUNT, shmem_init_inode);
-	return 0;
 }
 
 static void shmem_destroy_inodecache(void)
@@ -3991,9 +3995,7 @@ int __init shmem_init(void)
 	if (shmem_inode_cachep)
 		return 0;
 
-	error = shmem_init_inodecache();
-	if (error)
-		goto out3;
+	shmem_init_inodecache();
 
 	error = register_filesystem(&shmem_fs_type);
 	if (error) {
@@ -4020,7 +4022,6 @@ out1:
 	unregister_filesystem(&shmem_fs_type);
 out2:
 	shmem_destroy_inodecache();
-out3:
 	shm_mnt = ERR_PTR(error);
 	return error;
 }
@@ -4102,6 +4103,7 @@ bool shmem_huge_enabled(struct vm_area_struct *vma)
 			if (i_size >= HPAGE_PMD_SIZE &&
 					i_size >> PAGE_SHIFT >= off)
 				return true;
+			/* fall through */
 		case SHMEM_HUGE_ADVISE:
 			/* TODO: implement fadvise() hints */
 			return (vma->vm_flags & VM_HUGEPAGE);
@@ -4183,7 +4185,7 @@ static const struct dentry_operations anon_ops = {
 	.d_dname = simple_dname
 };
 
-static struct file *__shmem_file_setup(const char *name, loff_t size,
+static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, loff_t size,
 				       unsigned long flags, unsigned int i_flags)
 {
 	struct file *res;
@@ -4192,8 +4194,8 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
 	struct super_block *sb;
 	struct qstr this;
 
-	if (IS_ERR(shm_mnt))
-		return ERR_CAST(shm_mnt);
+	if (IS_ERR(mnt))
+		return ERR_CAST(mnt);
 
 	if (size < 0 || size > MAX_LFS_FILESIZE)
 		return ERR_PTR(-EINVAL);
@@ -4205,8 +4207,8 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
 	this.name = name;
 	this.len = strlen(name);
 	this.hash = 0; /* will go */
-	sb = shm_mnt->mnt_sb;
-	path.mnt = mntget(shm_mnt);
+	sb = mnt->mnt_sb;
+	path.mnt = mntget(mnt);
 	path.dentry = d_alloc_pseudo(sb, &this);
 	if (!path.dentry)
 		goto put_memory;
@@ -4251,7 +4253,7 @@ put_path:
  */
 struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned long flags)
 {
-	return __shmem_file_setup(name, size, flags, S_PRIVATE);
+	return __shmem_file_setup(shm_mnt, name, size, flags, S_PRIVATE);
 }
 
 /**
@@ -4262,11 +4264,25 @@ struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned lon
  */
 struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags)
 {
-	return __shmem_file_setup(name, size, flags, 0);
+	return __shmem_file_setup(shm_mnt, name, size, flags, 0);
 }
 EXPORT_SYMBOL_GPL(shmem_file_setup);
 
 /**
+ * shmem_file_setup_with_mnt - get an unlinked file living in tmpfs
+ * @mnt: the tmpfs mount where the file will be created
+ * @name: name for dentry (to be seen in /proc/<pid>/maps
+ * @size: size to be set for the file
+ * @flags: VM_NORESERVE suppresses pre-accounting of the entire object size
+ */
+struct file *shmem_file_setup_with_mnt(struct vfsmount *mnt, const char *name,
+				       loff_t size, unsigned long flags)
+{
+	return __shmem_file_setup(mnt, name, size, flags, 0);
+}
+EXPORT_SYMBOL_GPL(shmem_file_setup_with_mnt);
+
+/**
  * shmem_zero_setup - setup a shared anonymous mapping
  * @vma: the vma to be mmapped is prepared by do_mmap_pgoff
  */
@@ -4281,7 +4297,7 @@ int shmem_zero_setup(struct vm_area_struct *vma)
 	 * accessible to the user through its mapping, use S_PRIVATE flag to
 	 * bypass file security, in the same way as shmem_kernel_file_setup().
 	 */
-	file = __shmem_file_setup("dev/zero", size, vma->vm_flags, S_PRIVATE);
+	file = shmem_kernel_file_setup("dev/zero", size, vma->vm_flags);
 	if (IS_ERR(file))
 		return PTR_ERR(file);