autofs4: cleanup redundant readir code

The mount triggering functionality of readdir and related functions is no
longer used (and is quite broken as well).  The unused portions have been
removed.

Signed-off-by: Ian Kent <raven@themaw.net>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 16 insertions, 133 deletions

diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index 87352654ff4e..51c873ca8e8d 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -25,8 +25,6 @@ static int autofs4_dir_rmdir(struct inode *,struct dentry *);
 static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
 static int autofs4_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long);
 static int autofs4_dir_open(struct inode *inode, struct file *file);
-static int autofs4_dir_close(struct inode *inode, struct file *file);
-static int autofs4_dir_readdir(struct file * filp, void * dirent, filldir_t filldir);
 static int autofs4_root_readdir(struct file * filp, void * dirent, filldir_t filldir);
 static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *);
 static void *autofs4_follow_link(struct dentry *, struct nameidata *);
@@ -44,9 +42,9 @@ const struct file_operations autofs4_root_operations = {
 
 const struct file_operations autofs4_dir_operations = {
         .open           = autofs4_dir_open,
-        .release        = autofs4_dir_close,
+        .release        = dcache_dir_close,
         .read           = generic_read_dir,
-        .readdir        = autofs4_dir_readdir,
+        .readdir        = dcache_readdir,
 };
 
 const struct inode_operations autofs4_indirect_root_inode_operations = {
@@ -98,17 +96,7 @@ static int autofs4_root_readdir(struct file *file, void *dirent,
 static int autofs4_dir_open(struct inode *inode, struct file *file)
 {
         struct dentry *dentry = file->f_path.dentry;
-        struct vfsmount *mnt = file->f_path.mnt;
         struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
-        struct dentry *cursor;
-        int status;
-
-        status = dcache_dir_open(inode, file);
-        if (status)
-                goto out;
-
-        cursor = file->private_data;
-        cursor->d_fsdata = NULL;
 
         DPRINTK("file=%p dentry=%p %.*s",
                 file, dentry, dentry->d_name.len, dentry->d_name.name);
@@ -116,129 +104,24 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)
         if (autofs4_oz_mode(sbi))
                 goto out;
 
-        if (autofs4_ispending(dentry)) {
-                DPRINTK("dentry busy");
-                dcache_dir_close(inode, file);
-                status = -EBUSY;
-                goto out;
-        }
-
-        status = -ENOENT;
-        if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) {
-                struct nameidata nd;
-                int empty, ret;
-
-                /* In case there are stale directory dentrys from a failed mount */
-                spin_lock(&dcache_lock);
-                empty = list_empty(&dentry->d_subdirs);
+        /*
+         * An empty directory in an autofs file system is always a
+         * mount point. The daemon must have failed to mount this
+         * during lookup so it doesn't exist. This can happen, for
+         * example, if user space returns an incorrect status for a
+         * mount request. Otherwise we're doing a readdir on the
+         * autofs file system so just let the libfs routines handle
+         * it.
+         */
+        spin_lock(&dcache_lock);
+        if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
                 spin_unlock(&dcache_lock);
-
-                if (!empty)
-                        d_invalidate(dentry);
-
-                nd.flags = LOOKUP_DIRECTORY;
-                ret = (dentry->d_op->d_revalidate)(dentry, &nd);
-
-                if (ret <= 0) {
-                        if (ret < 0)
-                                status = ret;
-                        dcache_dir_close(inode, file);
-                        goto out;
-                }
+                return -ENOENT;
         }
+        spin_unlock(&dcache_lock);
 
-        if (d_mountpoint(dentry)) {
-                struct file *fp = NULL;
-                struct path fp_path = { .dentry = dentry, .mnt = mnt };
-
-                path_get(&fp_path);
-
-                if (!autofs4_follow_mount(&fp_path.mnt, &fp_path.dentry)) {
-                        path_put(&fp_path);
-                        dcache_dir_close(inode, file);
-                        goto out;
-                }
-
-                fp = dentry_open(fp_path.dentry, fp_path.mnt, file->f_flags);
-                status = PTR_ERR(fp);
-                if (IS_ERR(fp)) {
-                        dcache_dir_close(inode, file);
-                        goto out;
-                }
-                cursor->d_fsdata = fp;
-        }
-        return 0;
-out:
-        return status;
-}
-
-static int autofs4_dir_close(struct inode *inode, struct file *file)
-{
-        struct dentry *dentry = file->f_path.dentry;
-        struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
-        struct dentry *cursor = file->private_data;
-        int status = 0;
-
-        DPRINTK("file=%p dentry=%p %.*s",
-                file, dentry, dentry->d_name.len, dentry->d_name.name);
-
-        if (autofs4_oz_mode(sbi))
-                goto out;
-
-        if (autofs4_ispending(dentry)) {
-                DPRINTK("dentry busy");
-                status = -EBUSY;
-                goto out;
-        }
-
-        if (d_mountpoint(dentry)) {
-                struct file *fp = cursor->d_fsdata;
-                if (!fp) {
-                        status = -ENOENT;
-                        goto out;
-                }
-                filp_close(fp, current->files);
-        }
-out:
-        dcache_dir_close(inode, file);
-        return status;
-}
-
-static int autofs4_dir_readdir(struct file *file, void *dirent, filldir_t filldir)
-{
-        struct dentry *dentry = file->f_path.dentry;
-        struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
-        struct dentry *cursor = file->private_data;
-        int status;
-
-        DPRINTK("file=%p dentry=%p %.*s",
-                file, dentry, dentry->d_name.len, dentry->d_name.name);
-
-        if (autofs4_oz_mode(sbi))
-                goto out;
-
-        if (autofs4_ispending(dentry)) {
-                DPRINTK("dentry busy");
-                return -EBUSY;
-        }
-
-        if (d_mountpoint(dentry)) {
-                struct file *fp = cursor->d_fsdata;
-
-                if (!fp)
-                        return -ENOENT;
-
-                if (!fp->f_op || !fp->f_op->readdir)
-                        goto out;
-
-                status = vfs_readdir(fp, filldir, dirent);
-                file->f_pos = fp->f_pos;
-                if (status)
-                        autofs4_copy_atime(file, fp);
-                return status;
-        }
 out:
-        return dcache_readdir(file, dirent, filldir);
+        return dcache_dir_open(inode, file);
 }
 
 static int try_to_fill_dentry(struct dentry *dentry, int flags)