From 117aff744a20a2a04ccdb36cd5978316e1af0c3a Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 18 Apr 2009 11:19:26 -0400 Subject: Fix autofs_expire() mnt should remain the same for all iterations through the list; as it is, if we have a busy mount, mnt follows into it and isn't restored for the next iteration. Signed-off-by: Al Viro --- fs/autofs/dirhash.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) (limited to 'fs/autofs') diff --git a/fs/autofs/dirhash.c b/fs/autofs/dirhash.c index bf8c8af98004..4eb4d8dfb2f1 100644 --- a/fs/autofs/dirhash.c +++ b/fs/autofs/dirhash.c @@ -39,10 +39,12 @@ struct autofs_dir_ent *autofs_expire(struct super_block *sb, { struct autofs_dirhash *dh = &sbi->dirhash; struct autofs_dir_ent *ent; - struct dentry *dentry; unsigned long timeout = sbi->exp_timeout; while (1) { + struct path path; + int umount_ok; + if ( list_empty(&dh->expiry_head) || sbi->catatonic ) return NULL; /* No entries */ /* We keep the list sorted by last_usage and want old stuff */ @@ -57,17 +59,17 @@ struct autofs_dir_ent *autofs_expire(struct super_block *sb, return ent; /* Symlinks are always expirable */ /* Get the dentry for the autofs subdirectory */ - dentry = ent->dentry; + path.dentry = ent->dentry; - if ( !dentry ) { + if (!path.dentry) { /* Should only happen in catatonic mode */ printk("autofs: dentry == NULL but inode range is directory, entry %s\n", ent->name); autofs_delete_usage(ent); continue; } - if ( !dentry->d_inode ) { - dput(dentry); + if (!path.dentry->d_inode) { + dput(path.dentry); printk("autofs: negative dentry on expiry queue: %s\n", ent->name); autofs_delete_usage(ent); @@ -76,29 +78,29 @@ struct autofs_dir_ent *autofs_expire(struct super_block *sb, /* Make sure entry is mounted and unused; note that dentry will point to the mounted-on-top root. */ - if (!S_ISDIR(dentry->d_inode->i_mode)||!d_mountpoint(dentry)) { + if (!S_ISDIR(path.dentry->d_inode->i_mode) || + !d_mountpoint(path.dentry)) { DPRINTK(("autofs: not expirable (not a mounted directory): %s\n", ent->name)); continue; } - mntget(mnt); - dget(dentry); - if (!follow_down(&mnt, &dentry)) { - dput(dentry); - mntput(mnt); + path.mnt = mnt; + path_get(&path); + if (!follow_down(&path.mnt, &path.dentry)) { + path_put(&path); DPRINTK(("autofs: not expirable (not a mounted directory): %s\n", ent->name)); continue; } - while (d_mountpoint(dentry) && follow_down(&mnt, &dentry)) + while (d_mountpoint(path.dentry) && + follow_down(&path.mnt, &path.dentry)) ; - dput(dentry); + umount_ok = may_umount(path.mnt); + path_put(&path); - if ( may_umount(mnt) ) { - mntput(mnt); + if (umount_ok) { DPRINTK(("autofs: signaling expire on %s\n", ent->name)); return ent; /* Expirable! */ } DPRINTK(("autofs: didn't expire due to may_umount: %s\n", ent->name)); - mntput(mnt); } return NULL; /* No expirable entries */ } -- cgit