vfs: add d_is_dir()

commit 44b1d53043c482225196e8a9cd9f35163a1b3336 upstream.

Add d_is_dir(dentry) helper which is analogous to S_ISDIR().

To avoid confusion, rename d_is_directory() to d_can_lookup().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/namei.c b/fs/namei.c
index bdea109..3cdf7ac 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1797,7 +1797,7 @@ static int link_path_walk(const char *name, struct nameidata *nd)
                        if (err)
                                return err;
                }
-               if (!d_is_directory(nd->path.dentry)) {
+               if (!d_can_lookup(nd->path.dentry)) {
                        err = -ENOTDIR; 
                        break;
                }
@@ -1818,7 +1818,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                struct dentry *root = nd->root.dentry;
                struct inode *inode = root->d_inode;
                if (*name) {
-                       if (!d_is_directory(root))
+                       if (!d_can_lookup(root))
                                return -ENOTDIR;
                        retval = inode_permission(inode, MAY_EXEC);
                        if (retval)
@@ -1874,7 +1874,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                dentry = f.file->f_path.dentry;
 
                if (*name) {
-                       if (!d_is_directory(dentry)) {
+                       if (!d_can_lookup(dentry)) {
                                fdput(f);
                                return -ENOTDIR;
                        }
@@ -1956,7 +1956,7 @@ static int path_lookupat(int dfd, const char *name,
                err = complete_walk(nd);
 
        if (!err && nd->flags & LOOKUP_DIRECTORY) {
-               if (!d_is_directory(nd->path.dentry)) {
+               if (!d_can_lookup(nd->path.dentry)) {
                        path_put(&nd->path);
                        err = -ENOTDIR;
                }
@@ -2416,11 +2416,11 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
            IS_IMMUTABLE(inode) || IS_SWAPFILE(inode))
                return -EPERM;
        if (isdir) {
-               if (!d_is_directory(victim) && !d_is_autodir(victim))
+               if (!d_is_dir(victim))
                        return -ENOTDIR;
                if (IS_ROOT(victim))
                        return -EBUSY;
-       } else if (d_is_directory(victim) || d_is_autodir(victim))
+       } else if (d_is_dir(victim))
                return -EISDIR;
        if (IS_DEADDIR(dir))
                return -ENOENT;
@@ -3018,11 +3018,10 @@ finish_open:
        }
        audit_inode(name, nd->path.dentry, 0);
        error = -EISDIR;
-       if ((open_flag & O_CREAT) &&
-           (d_is_directory(nd->path.dentry) || d_is_autodir(nd->path.dentry)))
+       if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry))
                goto out;
        error = -ENOTDIR;
-       if ((nd->flags & LOOKUP_DIRECTORY) && !d_is_directory(nd->path.dentry))
+       if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry))
                goto out;
        if (!S_ISREG(nd->inode->i_mode))
                will_truncate = false;
@@ -3746,7 +3745,7 @@ exit1:
 slashes:
        if (d_is_negative(dentry))
                error = -ENOENT;
-       else if (d_is_directory(dentry) || d_is_autodir(dentry))
+       else if (d_is_dir(dentry))
                error = -EISDIR;
        else
                error = -ENOTDIR;
@@ -4125,7 +4124,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
               struct inode **delegated_inode)
 {
        int error;
-       int is_dir = d_is_directory(old_dentry) || d_is_autodir(old_dentry);
+       int is_dir = d_is_dir(old_dentry);
        const unsigned char *old_name;
 
        if (old_dentry->d_inode == new_dentry->d_inode)
@@ -4218,7 +4217,7 @@ retry_deleg:
        if (d_is_negative(old_dentry))
                goto exit4;
        /* unless the source is a directory trailing slashes give -ENOTDIR */
-       if (!d_is_directory(old_dentry) && !d_is_autodir(old_dentry)) {
+       if (!d_is_dir(old_dentry)) {
                error = -ENOTDIR;
                if (oldnd.last.name[oldnd.last.len])
                        goto exit4;

diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index bf72e9a..3b50cac 100644 (file)
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -429,7 +429,7 @@ static inline unsigned __d_entry_type(const struct dentry *dentry)
        return dentry->d_flags & DCACHE_ENTRY_TYPE;
 }
 
-static inline bool d_is_directory(const struct dentry *dentry)
+static inline bool d_can_lookup(const struct dentry *dentry)
 {
        return __d_entry_type(dentry) == DCACHE_DIRECTORY_TYPE;
 }
@@ -439,6 +439,11 @@ static inline bool d_is_autodir(const struct dentry *dentry)
        return __d_entry_type(dentry) == DCACHE_AUTODIR_TYPE;
 }
 
+static inline bool d_is_dir(const struct dentry *dentry)
+{
+       return d_can_lookup(dentry) || d_is_autodir(dentry);
+}
+
 static inline bool d_is_symlink(const struct dentry *dentry)
 {
        return __d_entry_type(dentry) == DCACHE_SYMLINK_TYPE;