hostfs: support rename flags

Support RENAME_NOREPLACE and RENAME_EXCHANGE flags on hostfs if the
underlying filesystem supports it.

Since renameat2(2) is not yet in any libc, use syscall(2) to invoke the
renameat2 syscall.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Miklos Szeredi 2014-07-23 15:15:35 +02:00 committed by Al Viro
parent 37456771c5
commit 9a423bb6e3
3 changed files with 49 additions and 10 deletions

View file

@ -89,6 +89,7 @@ extern int do_mknod(const char *file, int mode, unsigned int major,
extern int link_file(const char *from, const char *to);
extern int hostfs_do_readlink(char *file, char *buf, int size);
extern int rename_file(char *from, char *to);
extern int rename2_file(char *from, char *to, unsigned int flags);
extern int do_statfs(char *root, long *bsize_out, long long *blocks_out,
long long *bfree_out, long long *bavail_out,
long long *files_out, long long *ffree_out,

View file

@ -741,21 +741,31 @@ static int hostfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
return err;
}
static int hostfs_rename(struct inode *from_ino, struct dentry *from,
struct inode *to_ino, struct dentry *to)
static int hostfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry,
unsigned int flags)
{
char *from_name, *to_name;
char *old_name, *new_name;
int err;
if ((from_name = dentry_name(from)) == NULL)
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
return -EINVAL;
old_name = dentry_name(old_dentry);
if (old_name == NULL)
return -ENOMEM;
if ((to_name = dentry_name(to)) == NULL) {
__putname(from_name);
new_name = dentry_name(new_dentry);
if (new_name == NULL) {
__putname(old_name);
return -ENOMEM;
}
err = rename_file(from_name, to_name);
__putname(from_name);
__putname(to_name);
if (!flags)
err = rename_file(old_name, new_name);
else
err = rename2_file(old_name, new_name, flags);
__putname(old_name);
__putname(new_name);
return err;
}
@ -867,7 +877,7 @@ static const struct inode_operations hostfs_dir_iops = {
.mkdir = hostfs_mkdir,
.rmdir = hostfs_rmdir,
.mknod = hostfs_mknod,
.rename = hostfs_rename,
.rename2 = hostfs_rename2,
.permission = hostfs_permission,
.setattr = hostfs_setattr,
};

View file

@ -14,6 +14,7 @@
#include <sys/time.h>
#include <sys/types.h>
#include <sys/vfs.h>
#include <sys/syscall.h>
#include "hostfs.h"
#include <utime.h>
@ -360,6 +361,33 @@ int rename_file(char *from, char *to)
return 0;
}
int rename2_file(char *from, char *to, unsigned int flags)
{
int err;
#ifndef SYS_renameat2
# ifdef __x86_64__
# define SYS_renameat2 316
# endif
# ifdef __i386__
# define SYS_renameat2 353
# endif
#endif
#ifdef SYS_renameat2
err = syscall(SYS_renameat2, AT_FDCWD, from, AT_FDCWD, to, flags);
if (err < 0) {
if (errno != ENOSYS)
return -errno;
else
return -EINVAL;
}
return 0;
#else
return -EINVAL;
#endif
}
int do_statfs(char *root, long *bsize_out, long long *blocks_out,
long long *bfree_out, long long *bavail_out,
long long *files_out, long long *ffree_out,