On Sat, 2021-03-13 at 04:38 +0000, Al Viro wrote:
> inode_wrong_type(inode, mode) returns true if setting inode->i_mode
> to given value would've changed the inode type. We have enough of
> those checks open-coded to make a helper worthwhile.
>
> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> ---
> fs/9p/vfs_inode.c | 4 ++--
> fs/9p/vfs_inode_dotl.c | 4 ++--
> fs/cifs/inode.c | 5 ++---
> fs/fuse/dir.c | 6 +++---
> fs/fuse/inode.c | 2 +-
> fs/fuse/readdir.c | 2 +-
> fs/nfs/inode.c | 6 +++---
> fs/nfsd/nfsproc.c | 2 +-
> fs/overlayfs/namei.c | 4 ++--
> include/linux/fs.h | 5 +++++
> 10 files changed, 22 insertions(+), 18 deletions(-)
>
> diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
> index 8d97f0b45e9c..795706520b5e 100644
> --- a/fs/9p/vfs_inode.c
> +++ b/fs/9p/vfs_inode.c
> @@ -399,7 +399,7 @@ static int v9fs_test_inode(struct inode *inode, void *data)
>
>
> umode = p9mode2unixmode(v9ses, st, &rdev);
> /* don't match inode of different type */
> - if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
> + if (inode_wrong_type(inode, umode))
> return 0;
>
>
> /* compare qid details */
> @@ -1390,7 +1390,7 @@ int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
> * Don't update inode if the file type is different
> */
> umode = p9mode2unixmode(v9ses, st, &rdev);
> - if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
> + if (inode_wrong_type(inode, umode))
> goto out;
>
>
> /*
> diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
> index 1dc7af046615..df0b87b05c42 100644
> --- a/fs/9p/vfs_inode_dotl.c
> +++ b/fs/9p/vfs_inode_dotl.c
> @@ -59,7 +59,7 @@ static int v9fs_test_inode_dotl(struct inode *inode, void *data)
> struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
>
>
> /* don't match inode of different type */
> - if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
> + if (inode_wrong_type(inode, st->st_mode))
> return 0;
>
>
> if (inode->i_generation != st->st_gen)
> @@ -959,7 +959,7 @@ int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
> /*
> * Don't update inode if the file type is different
> */
> - if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
> + if (inode_wrong_type(inode, st->st_mode))
> goto out;
>
>
> /*
> diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
> index 7c61bc9573c0..d46b36d52211 100644
> --- a/fs/cifs/inode.c
> +++ b/fs/cifs/inode.c
> @@ -426,8 +426,7 @@ int cifs_get_inode_info_unix(struct inode **pinode,
> }
>
>
> /* if filetype is different, return error */
> - if (unlikely(((*pinode)->i_mode & S_IFMT) !=
> - (fattr.cf_mode & S_IFMT))) {
> + if (unlikely(inode_wrong_type(*pinode, fattr.cf_mode))) {
> CIFS_I(*pinode)->time = 0; /* force reval */
> rc = -ESTALE;
> goto cgiiu_exit;
> @@ -1249,7 +1248,7 @@ cifs_find_inode(struct inode *inode, void *opaque)
> return 0;
>
>
> /* don't match inode of different type */
> - if ((inode->i_mode & S_IFMT) != (fattr->cf_mode & S_IFMT))
> + if (inode_wrong_type(inode, fattr->cf_mode))
> return 0;
>
>
> /* if it's not a directory or has no dentries, then flag it */
> diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
> index 06a18700a845..2400b98e8808 100644
> --- a/fs/fuse/dir.c
> +++ b/fs/fuse/dir.c
> @@ -252,7 +252,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
> if (ret == -ENOMEM)
> goto out;
> if (ret || fuse_invalid_attr(&outarg.attr) ||
> - (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
> + inode_wrong_type(inode, outarg.attr.mode))
> goto invalid;
>
>
> forget_all_cached_acls(inode);
> @@ -1054,7 +1054,7 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
> err = fuse_simple_request(fm, &args);
> if (!err) {
> if (fuse_invalid_attr(&outarg.attr) ||
> - (inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
> + inode_wrong_type(inode, outarg.attr.mode)) {
> fuse_make_bad(inode);
> err = -EIO;
> } else {
> @@ -1703,7 +1703,7 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
> }
>
>
> if (fuse_invalid_attr(&outarg.attr) ||
> - (inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
> + inode_wrong_type(inode, outarg.attr.mode)) {
> fuse_make_bad(inode);
> err = -EIO;
> goto error;
> diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
> index b0e18b470e91..b4b956da3851 100644
> --- a/fs/fuse/inode.c
> +++ b/fs/fuse/inode.c
> @@ -350,7 +350,7 @@ struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
> inode->i_generation = generation;
> fuse_init_inode(inode, attr);
> unlock_new_inode(inode);
> - } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
> + } else if (inode_wrong_type(inode, attr->mode)) {
> /* Inode has changed type, any I/O on the old should fail */
> fuse_make_bad(inode);
> iput(inode);
> diff --git a/fs/fuse/readdir.c b/fs/fuse/readdir.c
> index 3441ffa740f3..277f7041d55a 100644
> --- a/fs/fuse/readdir.c
> +++ b/fs/fuse/readdir.c
> @@ -202,7 +202,7 @@ static int fuse_direntplus_link(struct file *file,
> inode = d_inode(dentry);
> if (!inode ||
> get_node_id(inode) != o->nodeid ||
> - ((o->attr.mode ^ inode->i_mode) & S_IFMT)) {
> + inode_wrong_type(inode, o->attr.mode)) {
> d_invalidate(dentry);
> dput(dentry);
> goto retry;
> diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
> index 749bbea14d99..b0da2408816d 100644
> --- a/fs/nfs/inode.c
> +++ b/fs/nfs/inode.c
> @@ -334,7 +334,7 @@ nfs_find_actor(struct inode *inode, void *opaque)
>
>
> if (NFS_FILEID(inode) != fattr->fileid)
> return 0;
> - if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
> + if (inode_wrong_type(inode, fattr->mode))
> return 0;
> if (nfs_compare_fh(NFS_FH(inode), fh))
> return 0;
> @@ -1460,7 +1460,7 @@ static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fat
> return 0;
> return -ESTALE;
> }
> - if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
> + if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode))
> return -ESTALE;
>
>
>
>
> @@ -1875,7 +1875,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
> /*
> * Make sure the inode's type hasn't changed.
> */
> - if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
> + if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode)) {
> /*
> * Big trouble! The inode has become a different object.
> */
> diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
> index a8d5449dd0e9..6d51687a0585 100644
> --- a/fs/nfsd/nfsproc.c
> +++ b/fs/nfsd/nfsproc.c
> @@ -381,7 +381,7 @@ nfsd_proc_create(struct svc_rqst *rqstp)
>
>
> /* Make sure the type and device matches */
> resp->status = nfserr_exist;
> - if (inode && type != (inode->i_mode & S_IFMT))
> + if (inode && inode_wrong_type(inode, type))
> goto out_unlock;
> }
>
>
> diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
> index 3fe05fb5d145..1d573972ce22 100644
> --- a/fs/overlayfs/namei.c
> +++ b/fs/overlayfs/namei.c
> @@ -371,7 +371,7 @@ int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
> return PTR_ERR(origin);
>
>
> if (upperdentry && !ovl_is_whiteout(upperdentry) &&
> - ((d_inode(origin)->i_mode ^ d_inode(upperdentry)->i_mode) & S_IFMT))
> + inode_wrong_type(d_inode(upperdentry), d_inode(origin)->i_mode))
> goto invalid;
>
>
> if (!*stackp)
> @@ -730,7 +730,7 @@ struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
> index = ERR_PTR(-ESTALE);
> goto out;
> } else if (ovl_dentry_weird(index) || ovl_is_whiteout(index) ||
> - ((inode->i_mode ^ d_inode(origin)->i_mode) & S_IFMT)) {
> + inode_wrong_type(inode, d_inode(origin)->i_mode)) {
> /*
> * Index should always be of the same file type as origin
> * except for the case of a whiteout index. A whiteout
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index ec8f3ddf4a6a..9e0d76a41229 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -2884,6 +2884,11 @@ static inline bool execute_ok(struct inode *inode)
> return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode);
> }
>
>
> +static inline bool inode_wrong_type(const struct inode *inode, umode_t mode)
> +{
> + return (inode->i_mode ^ mode) & S_IFMT;
> +}
> +
> static inline void file_start_write(struct file *file)
> {
> if (!S_ISREG(file_inode(file)->i_mode))
I like the new helper -- much easier to read.
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
