new wrapper: alloc_file_pseudo()
takes inode, vfsmount, name, O_... flags and file_operations and
either returns a new struct file (in which case inode reference we
held is consumed) or returns ERR_PTR(), in which case no refcounts
are altered.
converted aio_private_file() and sock_alloc_file() to it
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/aio.c b/fs/aio.c
index 9eea538..c3a8bac 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -215,9 +215,7 @@ static const struct address_space_operations aio_ctx_aops;
static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages)
{
- struct qstr this = QSTR_INIT("[aio]", 5);
struct file *file;
- struct path path;
struct inode *inode = alloc_anon_inode(aio_mnt->mnt_sb);
if (IS_ERR(inode))
return ERR_CAST(inode);
@@ -226,27 +224,17 @@ static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages)
inode->i_mapping->private_data = ctx;
inode->i_size = PAGE_SIZE * nr_pages;
- path.dentry = d_alloc_pseudo(aio_mnt->mnt_sb, &this);
- if (!path.dentry) {
- iput(inode);
- return ERR_PTR(-ENOMEM);
- }
- path.mnt = mntget(aio_mnt);
-
- d_instantiate(path.dentry, inode);
- file = alloc_file(&path, O_RDWR, &aio_ring_fops);
+ file = alloc_file_pseudo(inode, aio_mnt, "[aio]",
+ O_RDWR, &aio_ring_fops);
if (IS_ERR(file))
- path_put(&path);
+ iput(inode);
return file;
}
static struct dentry *aio_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
- static const struct dentry_operations ops = {
- .d_dname = simple_dname,
- };
- struct dentry *root = mount_pseudo(fs_type, "aio:", NULL, &ops,
+ struct dentry *root = mount_pseudo(fs_type, "aio:", NULL, NULL,
AIO_RING_MAGIC);
if (!IS_ERR(root))
diff --git a/fs/file_table.c b/fs/file_table.c
index 9b70ed2..6b37239 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -184,6 +184,33 @@ struct file *alloc_file(const struct path *path, int flags,
}
EXPORT_SYMBOL(alloc_file);
+struct file *alloc_file_pseudo(struct inode *inode, struct vfsmount *mnt,
+ const char *name, int flags,
+ const struct file_operations *fops)
+{
+ static const struct dentry_operations anon_ops = {
+ .d_dname = simple_dname
+ };
+ struct qstr this = QSTR_INIT(name, strlen(name));
+ struct path path;
+ struct file *file;
+
+ path.dentry = d_alloc_pseudo(mnt->mnt_sb, &this);
+ if (!path.dentry)
+ return ERR_PTR(-ENOMEM);
+ if (!mnt->mnt_sb->s_d_op)
+ d_set_d_op(path.dentry, &anon_ops);
+ path.mnt = mntget(mnt);
+ d_instantiate(path.dentry, inode);
+ file = alloc_file(&path, flags, fops);
+ if (IS_ERR(file)) {
+ ihold(inode);
+ path_put(&path);
+ }
+ return file;
+}
+EXPORT_SYMBOL(alloc_file_pseudo);
+
/* the real guts of fput() - releasing the last reference to file
*/
static void __fput(struct file *file)
