]> Pileus Git - ~andy/linux/blobdiff - fs/namei.c
VFS: Put a small type field into struct dentry::d_flags
[~andy/linux] / fs / namei.c
index e5c0118ba9f8ce02e918bc053ede25f316ca21c7..e1fa43346c612e5e65e75c3e83735fddebf7f236 100644 (file)
@@ -1501,18 +1501,9 @@ static void terminate_walk(struct nameidata *nd)
  * so we keep a cache of "no, this doesn't need follow_link"
  * for the common case.
  */
-static inline int should_follow_link(struct inode *inode, int follow)
+static inline int should_follow_link(struct dentry *dentry, int follow)
 {
-       if (unlikely(!(inode->i_opflags & IOP_NOFOLLOW))) {
-               if (likely(inode->i_op->follow_link))
-                       return follow;
-
-               /* This gets set once for the inode lifetime */
-               spin_lock(&inode->i_lock);
-               inode->i_opflags |= IOP_NOFOLLOW;
-               spin_unlock(&inode->i_lock);
-       }
-       return 0;
+       return unlikely(d_is_symlink(dentry)) ? follow : 0;
 }
 
 static inline int walk_component(struct nameidata *nd, struct path *path,
@@ -1542,7 +1533,7 @@ static inline int walk_component(struct nameidata *nd, struct path *path,
        if (!inode)
                goto out_path_put;
 
-       if (should_follow_link(inode, follow)) {
+       if (should_follow_link(path->dentry, follow)) {
                if (nd->flags & LOOKUP_RCU) {
                        if (unlikely(unlazy_walk(nd, path->dentry))) {
                                err = -ECHILD;
@@ -1600,26 +1591,6 @@ static inline int nested_symlink(struct path *path, struct nameidata *nd)
        return res;
 }
 
-/*
- * We really don't want to look at inode->i_op->lookup
- * when we don't have to. So we keep a cache bit in
- * the inode ->i_opflags field that says "yes, we can
- * do lookup on this inode".
- */
-static inline int can_lookup(struct inode *inode)
-{
-       if (likely(inode->i_opflags & IOP_LOOKUP))
-               return 1;
-       if (likely(!inode->i_op->lookup))
-               return 0;
-
-       /* We do this once for the lifetime of the inode */
-       spin_lock(&inode->i_lock);
-       inode->i_opflags |= IOP_LOOKUP;
-       spin_unlock(&inode->i_lock);
-       return 1;
-}
-
 /*
  * We can do the critical dentry name comparison and hashing
  * operations one word at a time, but we are limited to:
@@ -1823,7 +1794,7 @@ static int link_path_walk(const char *name, struct nameidata *nd)
                        if (err)
                                return err;
                }
-               if (!can_lookup(nd->inode)) {
+               if (!d_is_directory(nd->path.dentry)) {
                        err = -ENOTDIR; 
                        break;
                }
@@ -1841,9 +1812,10 @@ static int path_init(int dfd, const char *name, unsigned int flags,
        nd->flags = flags | LOOKUP_JUMPED;
        nd->depth = 0;
        if (flags & LOOKUP_ROOT) {
-               struct inode *inode = nd->root.dentry->d_inode;
+               struct dentry *root = nd->root.dentry;
+               struct inode *inode = root->d_inode;
                if (*name) {
-                       if (!can_lookup(inode))
+                       if (!d_is_directory(root))
                                return -ENOTDIR;
                        retval = inode_permission(inode, MAY_EXEC);
                        if (retval)
@@ -1899,7 +1871,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
                dentry = f.file->f_path.dentry;
 
                if (*name) {
-                       if (!can_lookup(dentry->d_inode)) {
+                       if (!d_is_directory(dentry)) {
                                fdput(f);
                                return -ENOTDIR;
                        }
@@ -1981,7 +1953,7 @@ static int path_lookupat(int dfd, const char *name,
                err = complete_walk(nd);
 
        if (!err && nd->flags & LOOKUP_DIRECTORY) {
-               if (!can_lookup(nd->inode)) {
+               if (!d_is_directory(nd->path.dentry)) {
                        path_put(&nd->path);
                        err = -ENOTDIR;
                }
@@ -2273,7 +2245,7 @@ done:
        }
        path->dentry = dentry;
        path->mnt = mntget(nd->path.mnt);
-       if (should_follow_link(dentry->d_inode, nd->flags & LOOKUP_FOLLOW))
+       if (should_follow_link(dentry, nd->flags & LOOKUP_FOLLOW))
                return 1;
        follow_mount(path);
        error = 0;
@@ -2417,12 +2389,14 @@ static inline int check_sticky(struct inode *dir, struct inode *inode)
  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
  *     nfs_async_unlink().
  */
-static int may_delete(struct inode *dir,struct dentry *victim,int isdir)
+static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
 {
+       struct inode *inode = victim->d_inode;
        int error;
 
-       if (!victim->d_inode)
+       if (d_is_negative(victim))
                return -ENOENT;
+       BUG_ON(!inode);
 
        BUG_ON(victim->d_parent->d_inode != dir);
        audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
@@ -2432,15 +2406,16 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir)
                return error;
        if (IS_APPEND(dir))
                return -EPERM;
-       if (check_sticky(dir, victim->d_inode)||IS_APPEND(victim->d_inode)||
-           IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
+
+       if (check_sticky(dir, inode) || IS_APPEND(inode) ||
+           IS_IMMUTABLE(inode) || IS_SWAPFILE(inode))
                return -EPERM;
        if (isdir) {
-               if (!S_ISDIR(victim->d_inode->i_mode))
+               if (!d_is_directory(victim) && !d_is_autodir(victim))
                        return -ENOTDIR;
                if (IS_ROOT(victim))
                        return -EBUSY;
-       } else if (S_ISDIR(victim->d_inode->i_mode))
+       } else if (d_is_directory(victim) || d_is_autodir(victim))
                return -EISDIR;
        if (IS_DEADDIR(dir))
                return -ENOENT;
@@ -2974,7 +2949,7 @@ retry_lookup:
        /*
         * create/update audit record if it already exists.
         */
-       if (path->dentry->d_inode)
+       if (d_is_positive(path->dentry))
                audit_inode(name, path->dentry, 0);
 
        /*
@@ -3003,12 +2978,12 @@ retry_lookup:
 finish_lookup:
        /* we _can_ be in RCU mode here */
        error = -ENOENT;
-       if (!inode) {
+       if (d_is_negative(path->dentry)) {
                path_to_nameidata(path, nd);
                goto out;
        }
 
-       if (should_follow_link(inode, !symlink_ok)) {
+       if (should_follow_link(path->dentry, !symlink_ok)) {
                if (nd->flags & LOOKUP_RCU) {
                        if (unlikely(unlazy_walk(nd, path->dentry))) {
                                error = -ECHILD;
@@ -3037,10 +3012,11 @@ finish_open:
        }
        audit_inode(name, nd->path.dentry, 0);
        error = -EISDIR;
-       if ((open_flag & O_CREAT) && S_ISDIR(nd->inode->i_mode))
+       if ((open_flag & O_CREAT) &&
+           (d_is_directory(nd->path.dentry) || d_is_autodir(nd->path.dentry)))
                goto out;
        error = -ENOTDIR;
-       if ((nd->flags & LOOKUP_DIRECTORY) && !can_lookup(nd->inode))
+       if ((nd->flags & LOOKUP_DIRECTORY) && !d_is_directory(nd->path.dentry))
                goto out;
        if (!S_ISREG(nd->inode->i_mode))
                will_truncate = false;
@@ -3266,7 +3242,7 @@ struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt,
        nd.root.mnt = mnt;
        nd.root.dentry = dentry;
 
-       if (dentry->d_inode->i_op->follow_link && op->intent & LOOKUP_OPEN)
+       if (d_is_symlink(dentry) && op->intent & LOOKUP_OPEN)
                return ERR_PTR(-ELOOP);
 
        file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_RCU);
@@ -3316,8 +3292,9 @@ struct dentry *kern_path_create(int dfd, const char *pathname,
                goto unlock;
 
        error = -EEXIST;
-       if (dentry->d_inode)
+       if (d_is_positive(dentry))
                goto fail;
+
        /*
         * Special case - lookup gave negative, but... we had foo/bar/
         * From the vfs_mknod() POV we just have a negative dentry -
@@ -3706,7 +3683,7 @@ retry:
                if (nd.last.name[nd.last.len])
                        goto slashes;
                inode = dentry->d_inode;
-               if (!inode)
+               if (d_is_negative(dentry))
                        goto slashes;
                ihold(inode);
                error = security_path_unlink(&nd.path, dentry);
@@ -3731,8 +3708,12 @@ exit1:
        return error;
 
 slashes:
-       error = !dentry->d_inode ? -ENOENT :
-               S_ISDIR(dentry->d_inode->i_mode) ? -EISDIR : -ENOTDIR;
+       if (d_is_negative(dentry))
+               error = -ENOENT;
+       else if (d_is_directory(dentry) || d_is_autodir(dentry))
+               error = -EISDIR;
+       else
+               error = -ENOTDIR;
        goto exit2;
 }
 
@@ -4046,7 +4027,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
               struct inode *new_dir, struct dentry *new_dentry)
 {
        int error;
-       int is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
+       int is_dir = d_is_directory(old_dentry) || d_is_autodir(old_dentry);
        const unsigned char *old_name;
 
        if (old_dentry->d_inode == new_dentry->d_inode)
@@ -4134,10 +4115,10 @@ retry:
                goto exit3;
        /* source must exist */
        error = -ENOENT;
-       if (!old_dentry->d_inode)
+       if (d_is_negative(old_dentry))
                goto exit4;
        /* unless the source is a directory trailing slashes give -ENOTDIR */
-       if (!S_ISDIR(old_dentry->d_inode->i_mode)) {
+       if (!d_is_directory(old_dentry) && !d_is_autodir(old_dentry)) {
                error = -ENOTDIR;
                if (oldnd.last.name[oldnd.last.len])
                        goto exit4;