vfs: add renameat2 syscall
Add new renameat2 syscall, which is the same as renameat with an added
flags argument.
Pass flags to vfs_rename() and to i_op->rename() as well.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/namei.c b/fs/namei.c
index 12b8f56..ab4e48c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3980,6 +3980,7 @@
* @new_dir: parent of destination
* @new_dentry: destination
* @delegated_inode: returns an inode needing a delegation break
+ * @flags: rename flags
*
* The caller must hold multiple mutexes--see lock_rename()).
*
@@ -4023,7 +4024,7 @@
*/
int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry,
- struct inode **delegated_inode)
+ struct inode **delegated_inode, unsigned int flags)
{
int error;
bool is_dir = d_is_dir(old_dentry);
@@ -4048,6 +4049,9 @@
if (!old_dir->i_op->rename)
return -EPERM;
+ if (flags && !old_dir->i_op->rename2)
+ return -EINVAL;
+
/*
* If we are going to change the parent - check write permissions,
* we'll need to flip '..'.
@@ -4093,7 +4097,13 @@
goto out;
}
}
- error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
+ if (!flags) {
+ error = old_dir->i_op->rename(old_dir, old_dentry,
+ new_dir, new_dentry);
+ } else {
+ error = old_dir->i_op->rename2(old_dir, old_dentry,
+ new_dir, new_dentry, flags);
+ }
if (error)
goto out;
@@ -4118,8 +4128,8 @@
return error;
}
-SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
- int, newdfd, const char __user *, newname)
+SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname, unsigned int, flags)
{
struct dentry *old_dir, *new_dir;
struct dentry *old_dentry, *new_dentry;
@@ -4131,6 +4141,10 @@
unsigned int lookup_flags = 0;
bool should_retry = false;
int error;
+
+ if (flags)
+ return -EINVAL;
+
retry:
from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags);
if (IS_ERR(from)) {
@@ -4202,8 +4216,8 @@
if (error)
goto exit5;
error = vfs_rename(old_dir->d_inode, old_dentry,
- new_dir->d_inode, new_dentry,
- &delegated_inode);
+ new_dir->d_inode, new_dentry,
+ &delegated_inode, flags);
exit5:
dput(new_dentry);
exit4:
@@ -4233,9 +4247,15 @@
return error;
}
+SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname)
+{
+ return sys_renameat2(olddfd, oldname, newdfd, newname, 0);
+}
+
SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname)
{
- return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname);
+ return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
}
int vfs_readlink(struct dentry *dentry, char __user *buffer, int buflen, const char *link)