From 9a423bb6e3577bb372942edfb5d9d26632741d43 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 23 Jul 2014 15:15:35 +0200 Subject: [PATCH] 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 Cc: Richard Weinberger Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- fs/hostfs/hostfs.h | 1 + fs/hostfs/hostfs_kern.c | 30 ++++++++++++++++++++---------- fs/hostfs/hostfs_user.c | 28 ++++++++++++++++++++++++++++ 3 files changed, 49 insertions(+), 10 deletions(-) diff --git a/fs/hostfs/hostfs.h b/fs/hostfs/hostfs.h index 9c88da0e855a..4fcd40d6f308 100644 --- a/fs/hostfs/hostfs.h +++ b/fs/hostfs/hostfs.h @@ -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, diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c index bb529f3b7f2b..fd62cae0fdcb 100644 --- a/fs/hostfs/hostfs_kern.c +++ b/fs/hostfs/hostfs_kern.c @@ -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, }; diff --git a/fs/hostfs/hostfs_user.c b/fs/hostfs/hostfs_user.c index 67838f3aa20a..9765dab95cbd 100644 --- a/fs/hostfs/hostfs_user.c +++ b/fs/hostfs/hostfs_user.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "hostfs.h" #include @@ -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, -- 2.34.1