From: Miklos Szeredi <[email protected]> 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 <[email protected]> Cc: Richard Weinberger <[email protected]> --- fs/hostfs/hostfs.h | 1 + fs/hostfs/hostfs_kern.c | 35 ++++++++++++++++++++++++++--------- fs/hostfs/hostfs_user.c | 28 ++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+), 9 deletions(-) --- a/fs/hostfs/hostfs.h +++ b/fs/hostfs/hostfs.h @@ -89,6 +89,7 @@ extern int do_mknod(const char *file, in 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, --- a/fs/hostfs/hostfs_kern.c +++ b/fs/hostfs/hostfs_kern.c @@ -741,24 +741,40 @@ static int hostfs_mknod(struct inode *di 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; } +static int hostfs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + return hostfs_rename2(old_dir, old_dentry, new_dir, new_dentry, 0); +} + static int hostfs_permission(struct inode *ino, int desired) { char *name; @@ -868,6 +884,7 @@ static const struct inode_operations hos .rmdir = hostfs_rmdir, .mknod = hostfs_mknod, .rename = hostfs_rename, + .rename2 = hostfs_rename2, .permission = hostfs_permission, .setattr = hostfs_setattr, }; --- a/fs/hostfs/hostfs_user.c +++ b/fs/hostfs/hostfs_user.c @@ -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, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
