diff options
| -rw-r--r-- | fs/autofs4/expire.c | 162 |
1 files changed, 88 insertions, 74 deletions
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index 1695eda8ac18..d03bedc7369f 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -339,6 +339,89 @@ out: return NULL; } +/* Check if 'dentry' should expire, or return a nearby + * dentry that is suitable. + * If returned dentry is different from arg dentry, + * then a dget() reference was taken, else not. + */ +static struct dentry *should_expire(struct dentry *dentry, + struct vfsmount *mnt, + unsigned long timeout, + int how) +{ + int do_now = how & AUTOFS_EXP_IMMEDIATE; + int exp_leaves = how & AUTOFS_EXP_LEAVES; + struct autofs_info *ino = autofs4_dentry_ino(dentry); + unsigned int ino_count; + + /* No point expiring a pending mount */ + if (ino->flags & AUTOFS_INF_PENDING) + return NULL; + + /* + * Case 1: (i) indirect mount or top level pseudo direct mount + * (autofs-4.1). + * (ii) indirect mount with offset mount, check the "/" + * offset (autofs-5.0+). + */ + if (d_mountpoint(dentry)) { + DPRINTK("checking mountpoint %p %.*s", + dentry, (int)dentry->d_name.len, dentry->d_name.name); + + /* Can we umount this guy */ + if (autofs4_mount_busy(mnt, dentry)) + return NULL; + + /* Can we expire this guy */ + if (autofs4_can_expire(dentry, timeout, do_now)) + return dentry; + return NULL; + } + + if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) { + DPRINTK("checking symlink %p %.*s", + dentry, (int)dentry->d_name.len, dentry->d_name.name); + /* + * A symlink can't be "busy" in the usual sense so + * just check last used for expire timeout. + */ + if (autofs4_can_expire(dentry, timeout, do_now)) + return dentry; + return NULL; + } + + if (simple_empty(dentry)) + return NULL; + + /* Case 2: tree mount, expire iff entire tree is not busy */ + if (!exp_leaves) { + /* Path walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (d_count(dentry) > ino_count) + return NULL; + + if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) + return dentry; + /* + * Case 3: pseudo direct mount, expire individual leaves + * (autofs-4.1). + */ + } else { + /* Path walk currently on this dentry? */ + struct dentry *expired; + ino_count = atomic_read(&ino->count) + 1; + if (d_count(dentry) > ino_count) + return NULL; + + expired = autofs4_check_leaves(mnt, dentry, timeout, do_now); + if (expired) { + if (expired == dentry) + dput(dentry); + return expired; + } + } + return NULL; +} /* * Find an eligible tree to time-out * A tree is eligible if :- @@ -353,11 +436,8 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb, unsigned long timeout; struct dentry *root = sb->s_root; struct dentry *dentry; - struct dentry *expired = NULL; - int do_now = how & AUTOFS_EXP_IMMEDIATE; - int exp_leaves = how & AUTOFS_EXP_LEAVES; + struct dentry *expired; struct autofs_info *ino; - unsigned int ino_count; if (!root) return NULL; @@ -368,78 +448,12 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb, dentry = NULL; while ((dentry = get_next_positive_subdir(dentry, root))) { spin_lock(&sbi->fs_lock); - ino = autofs4_dentry_ino(dentry); - /* No point expiring a pending mount */ - if (ino->flags & AUTOFS_INF_PENDING) - goto next; - - /* - * Case 1: (i) indirect mount or top level pseudo direct mount - * (autofs-4.1). - * (ii) indirect mount with offset mount, check the "/" - * offset (autofs-5.0+). - */ - if (d_mountpoint(dentry)) { - DPRINTK("checking mountpoint %p %.*s", - dentry, (int)dentry->d_name.len, dentry->d_name.name); - - /* Can we umount this guy */ - if (autofs4_mount_busy(mnt, dentry)) - goto next; - - /* Can we expire this guy */ - if (autofs4_can_expire(dentry, timeout, do_now)) { - expired = dentry; - goto found; - } - goto next; - } - - if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) { - DPRINTK("checking symlink %p %.*s", - dentry, (int)dentry->d_name.len, dentry->d_name.name); - /* - * A symlink can't be "busy" in the usual sense so - * just check last used for expire timeout. - */ - if (autofs4_can_expire(dentry, timeout, do_now)) { - expired = dentry; - goto found; - } - goto next; - } - - if (simple_empty(dentry)) - goto next; - - /* Case 2: tree mount, expire iff entire tree is not busy */ - if (!exp_leaves) { - /* Path walk currently on this dentry? */ - ino_count = atomic_read(&ino->count) + 1; - if (d_count(dentry) > ino_count) - goto next; - - if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) { - expired = dentry; - goto found; - } - /* - * Case 3: pseudo direct mount, expire individual leaves - * (autofs-4.1). - */ - } else { - /* Path walk currently on this dentry? */ - ino_count = atomic_read(&ino->count) + 1; - if (d_count(dentry) > ino_count) - goto next; - - expired = autofs4_check_leaves(mnt, dentry, timeout, do_now); - if (expired) { + expired = should_expire(dentry, mnt, timeout, how); + if (expired) { + if (expired != dentry) dput(dentry); - goto found; - } + goto found; } -next: spin_unlock(&sbi->fs_lock); } return NULL; |