]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - fs/autofs4/root.c
[PATCH] autofs4: pending flag not cleared on mount fail
[linux-2.6-omap-h63xx.git] / fs / autofs4 / root.c
index 3a4a5b47575ceb53afaa09fa5f3265b6fa37259b..563ef9d7da9ffa858ad754217861f4e2292b30ea 100644 (file)
@@ -4,7 +4,7 @@
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
  *  Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
- *  Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ *  Copyright 2001-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
@@ -30,8 +30,9 @@ 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 *);
 
-struct file_operations autofs4_root_operations = {
+const struct file_operations autofs4_root_operations = {
        .open           = dcache_dir_open,
        .release        = dcache_dir_close,
        .read           = generic_read_dir,
@@ -39,14 +40,14 @@ struct file_operations autofs4_root_operations = {
        .ioctl          = autofs4_root_ioctl,
 };
 
-struct file_operations autofs4_dir_operations = {
+const struct file_operations autofs4_dir_operations = {
        .open           = autofs4_dir_open,
        .release        = autofs4_dir_close,
        .read           = generic_read_dir,
        .readdir        = autofs4_dir_readdir,
 };
 
-struct inode_operations autofs4_root_inode_operations = {
+struct inode_operations autofs4_indirect_root_inode_operations = {
        .lookup         = autofs4_lookup,
        .unlink         = autofs4_dir_unlink,
        .symlink        = autofs4_dir_symlink,
@@ -54,6 +55,14 @@ struct inode_operations autofs4_root_inode_operations = {
        .rmdir          = autofs4_dir_rmdir,
 };
 
+struct inode_operations autofs4_direct_root_inode_operations = {
+       .lookup         = autofs4_lookup,
+       .unlink         = autofs4_dir_unlink,
+       .mkdir          = autofs4_dir_mkdir,
+       .rmdir          = autofs4_dir_rmdir,
+       .follow_link    = autofs4_follow_link,
+};
+
 struct inode_operations autofs4_dir_inode_operations = {
        .lookup         = autofs4_lookup,
        .unlink         = autofs4_dir_unlink,
@@ -84,24 +93,6 @@ static int autofs4_root_readdir(struct file *file, void *dirent,
        return dcache_readdir(file, dirent, filldir);
 }
 
-/* Update usage from here to top of tree, so that scan of
-   top-level directories will give a useful result */
-static void autofs4_update_usage(struct vfsmount *mnt, struct dentry *dentry)
-{
-       struct dentry *top = dentry->d_sb->s_root;
-
-       spin_lock(&dcache_lock);
-       for(; dentry != top; dentry = dentry->d_parent) {
-               struct autofs_info *ino = autofs4_dentry_ino(dentry);
-
-               if (ino) {
-                       touch_atime(mnt, dentry);
-                       ino->last_used = jiffies;
-               }
-       }
-       spin_unlock(&dcache_lock);
-}
-
 static int autofs4_dir_open(struct inode *inode, struct file *file)
 {
        struct dentry *dentry = file->f_dentry;
@@ -146,7 +137,9 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)
                nd.flags = LOOKUP_DIRECTORY;
                ret = (dentry->d_op->d_revalidate)(dentry, &nd);
 
-               if (!ret) {
+               if (ret <= 0) {
+                       if (ret < 0)
+                               status = ret;
                        dcache_dir_close(inode, file);
                        goto out;
                }
@@ -246,10 +239,9 @@ out:
        return dcache_readdir(file, dirent, filldir);
 }
 
-static int try_to_fill_dentry(struct vfsmount *mnt, struct dentry *dentry, int flags)
+static int try_to_fill_dentry(struct dentry *dentry, int flags)
 {
-       struct super_block *sb = mnt->mnt_sb;
-       struct autofs_sb_info *sbi = autofs4_sbi(sb);
+       struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
        struct autofs_info *ino = autofs4_dentry_ino(dentry);
        int status = 0;
 
@@ -271,7 +263,7 @@ static int try_to_fill_dentry(struct vfsmount *mnt, struct dentry *dentry, int f
                 */
                status = d_invalidate(dentry);
                if (status != -EBUSY)
-                       return 0;
+                       return -ENOENT;
        }
 
        DPRINTK("dentry=%p %.*s ino=%p",
@@ -289,18 +281,15 @@ static int try_to_fill_dentry(struct vfsmount *mnt, struct dentry *dentry, int f
 
                DPRINTK("mount done status=%d", status);
 
-               if (status && dentry->d_inode)
-                       return 0; /* Try to get the kernel to invalidate this dentry */
-
                /* Turn this into a real negative dentry? */
                if (status == -ENOENT) {
                        spin_lock(&dentry->d_lock);
                        dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
                        spin_unlock(&dentry->d_lock);
-                       return 0;
+                       return status;
                } else if (status) {
                        /* Return a negative dentry, but leave it "pending" */
-                       return 0;
+                       return status;
                }
        /* Trigger mount for path component or follow link */
        } else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
@@ -319,17 +308,10 @@ static int try_to_fill_dentry(struct vfsmount *mnt, struct dentry *dentry, int f
                        spin_lock(&dentry->d_lock);
                        dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
                        spin_unlock(&dentry->d_lock);
-                       return 0;
+                       return status;
                }
        }
 
-       /*
-        * We don't update the usages for the autofs daemon itself, this
-        * is necessary for recursive autofs mounts
-        */
-       if (!autofs4_oz_mode(sbi))
-               autofs4_update_usage(mnt, dentry);
-
        /* Initialize expiry counter after successful mount */
        if (ino)
                ino->last_used = jiffies;
@@ -337,7 +319,72 @@ static int try_to_fill_dentry(struct vfsmount *mnt, struct dentry *dentry, int f
        spin_lock(&dentry->d_lock);
        dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
        spin_unlock(&dentry->d_lock);
-       return 1;
+       return status;
+}
+
+/* For autofs direct mounts the follow link triggers the mount */
+static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+       struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+       struct autofs_info *ino = autofs4_dentry_ino(dentry);
+       int oz_mode = autofs4_oz_mode(sbi);
+       unsigned int lookup_type;
+       int status;
+
+       DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d",
+               dentry, dentry->d_name.len, dentry->d_name.name, oz_mode,
+               nd->flags);
+
+       /* If it's our master or we shouldn't trigger a mount we're done */
+       lookup_type = nd->flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY);
+       if (oz_mode || !lookup_type)
+               goto done;
+
+       /* If an expire request is pending wait for it. */
+       if (ino && (ino->flags & AUTOFS_INF_EXPIRING)) {
+               DPRINTK("waiting for active request %p name=%.*s",
+                       dentry, dentry->d_name.len, dentry->d_name.name);
+
+               status = autofs4_wait(sbi, dentry, NFY_NONE);
+
+               DPRINTK("request done status=%d", status);
+       }
+
+       /*
+        * If the dentry contains directories then it is an
+        * autofs multi-mount with no root mount offset. So
+        * don't try to mount it again.
+        */
+       spin_lock(&dcache_lock);
+       if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
+               spin_unlock(&dcache_lock);
+
+               status = try_to_fill_dentry(dentry, 0);
+               if (status)
+                       goto out_error;
+
+               /*
+                * The mount succeeded but if there is no root mount
+                * it must be an autofs multi-mount with no root offset
+                * so we don't need to follow the mount.
+                */
+               if (d_mountpoint(dentry)) {
+                       if (!autofs4_follow_mount(&nd->mnt, &nd->dentry)) {
+                               status = -ENOENT;
+                               goto out_error;
+                       }
+               }
+
+               goto done;
+       }
+       spin_unlock(&dcache_lock);
+
+done:
+       return NULL;
+
+out_error:
+       path_release(nd);
+       return ERR_PTR(status);
 }
 
 /*
@@ -356,8 +403,18 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
 
        /* Pending dentry */
        if (autofs4_ispending(dentry)) {
-               if (!oz_mode)
-                       status = try_to_fill_dentry(nd->mnt, dentry, flags);
+               /* The daemon never causes a mount to trigger */
+               if (oz_mode)
+                       return 1;
+
+               /*
+                * A zero status is success otherwise we have a
+                * negative error code.
+                */
+               status = try_to_fill_dentry(dentry, flags);
+               if (status == 0)
+                               return 1;
+
                return status;
        }
 
@@ -369,24 +426,30 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
        spin_lock(&dcache_lock);
        if (S_ISDIR(dentry->d_inode->i_mode) &&
            !d_mountpoint(dentry) && 
-           simple_empty_nolock(dentry)) {
+           __simple_empty(dentry)) {
                DPRINTK("dentry=%p %.*s, emptydir",
                         dentry, dentry->d_name.len, dentry->d_name.name);
                spin_unlock(&dcache_lock);
-               if (!oz_mode)
-                       status = try_to_fill_dentry(nd->mnt, dentry, flags);
+               /* The daemon never causes a mount to trigger */
+               if (oz_mode)
+                       return 1;
+
+               /*
+                * A zero status is success otherwise we have a
+                * negative error code.
+                */
+               status = try_to_fill_dentry(dentry, flags);
+               if (status == 0)
+                       return 1;
+
                return status;
        }
        spin_unlock(&dcache_lock);
 
-       /* Update the usage list */
-       if (!oz_mode)
-               autofs4_update_usage(nd->mnt, dentry);
-
        return 1;
 }
 
-static void autofs4_dentry_release(struct dentry *de)
+void autofs4_dentry_release(struct dentry *de)
 {
        struct autofs_info *inf;
 
@@ -474,6 +537,9 @@ static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, s
                            return ERR_PTR(-ERESTARTNOINTR);
                        }
                }
+               spin_lock(&dentry->d_lock);
+               dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
+               spin_unlock(&dentry->d_lock);
        }
 
        /*
@@ -729,7 +795,7 @@ static inline int autofs4_ask_umount(struct vfsmount *mnt, int __user *p)
 {
        int status = 0;
 
-       if (may_umount(mnt) == 0)
+       if (may_umount(mnt))
                status = 1;
 
        DPRINTK("returning %d", status);