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Diffstat (limited to 'fs/autofs4/expire.c')
-rw-r--r--fs/autofs4/expire.c109
1 files changed, 86 insertions, 23 deletions
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index 894fee54d4d..cde2f8e8935 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -244,10 +244,10 @@ cont:
}
/* Check if we can expire a direct mount (possibly a tree) */
-static struct dentry *autofs4_expire_direct(struct super_block *sb,
- struct vfsmount *mnt,
- struct autofs_sb_info *sbi,
- int how)
+struct dentry *autofs4_expire_direct(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi,
+ int how)
{
unsigned long timeout;
struct dentry *root = dget(sb->s_root);
@@ -259,13 +259,15 @@ static struct dentry *autofs4_expire_direct(struct super_block *sb,
now = jiffies;
timeout = sbi->exp_timeout;
- /* Lock the tree as we must expire as a whole */
spin_lock(&sbi->fs_lock);
if (!autofs4_direct_busy(mnt, root, timeout, do_now)) {
struct autofs_info *ino = autofs4_dentry_ino(root);
-
- /* Set this flag early to catch sys_chdir and the like */
+ if (d_mountpoint(root)) {
+ ino->flags |= AUTOFS_INF_MOUNTPOINT;
+ root->d_mounted--;
+ }
ino->flags |= AUTOFS_INF_EXPIRING;
+ init_completion(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
return root;
}
@@ -281,10 +283,10 @@ static struct dentry *autofs4_expire_direct(struct super_block *sb,
* - it is unused by any user process
* - it has been unused for exp_timeout time
*/
-static struct dentry *autofs4_expire_indirect(struct super_block *sb,
- struct vfsmount *mnt,
- struct autofs_sb_info *sbi,
- int how)
+struct dentry *autofs4_expire_indirect(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi,
+ int how)
{
unsigned long timeout;
struct dentry *root = sb->s_root;
@@ -292,6 +294,8 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
struct list_head *next;
int do_now = how & AUTOFS_EXP_IMMEDIATE;
int exp_leaves = how & AUTOFS_EXP_LEAVES;
+ struct autofs_info *ino;
+ unsigned int ino_count;
if (!root)
return NULL;
@@ -316,6 +320,9 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
dentry = dget(dentry);
spin_unlock(&dcache_lock);
+ spin_lock(&sbi->fs_lock);
+ ino = autofs4_dentry_ino(dentry);
+
/*
* Case 1: (i) indirect mount or top level pseudo direct mount
* (autofs-4.1).
@@ -326,6 +333,11 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
DPRINTK("checking mountpoint %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
+ /* Path walk currently on this dentry? */
+ ino_count = atomic_read(&ino->count) + 2;
+ if (atomic_read(&dentry->d_count) > ino_count)
+ goto next;
+
/* Can we umount this guy */
if (autofs4_mount_busy(mnt, dentry))
goto next;
@@ -343,23 +355,25 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
/* Case 2: tree mount, expire iff entire tree is not busy */
if (!exp_leaves) {
- /* Lock the tree as we must expire as a whole */
- spin_lock(&sbi->fs_lock);
- if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
- struct autofs_info *inf = autofs4_dentry_ino(dentry);
+ /* Path walk currently on this dentry? */
+ ino_count = atomic_read(&ino->count) + 1;
+ if (atomic_read(&dentry->d_count) > ino_count)
+ goto next;
- /* Set this flag early to catch sys_chdir and the like */
- inf->flags |= AUTOFS_INF_EXPIRING;
- spin_unlock(&sbi->fs_lock);
+ if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
expired = dentry;
goto found;
}
- spin_unlock(&sbi->fs_lock);
/*
* 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 (atomic_read(&dentry->d_count) > ino_count)
+ goto next;
+
expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
if (expired) {
dput(dentry);
@@ -367,6 +381,7 @@ static struct dentry *autofs4_expire_indirect(struct super_block *sb,
}
}
next:
+ spin_unlock(&sbi->fs_lock);
dput(dentry);
spin_lock(&dcache_lock);
next = next->next;
@@ -377,12 +392,45 @@ next:
found:
DPRINTK("returning %p %.*s",
expired, (int)expired->d_name.len, expired->d_name.name);
+ ino = autofs4_dentry_ino(expired);
+ ino->flags |= AUTOFS_INF_EXPIRING;
+ init_completion(&ino->expire_complete);
+ spin_unlock(&sbi->fs_lock);
spin_lock(&dcache_lock);
list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child);
spin_unlock(&dcache_lock);
return expired;
}
+int autofs4_expire_wait(struct dentry *dentry)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ int status;
+
+ /* Block on any pending expire */
+ spin_lock(&sbi->fs_lock);
+ if (ino->flags & AUTOFS_INF_EXPIRING) {
+ spin_unlock(&sbi->fs_lock);
+
+ DPRINTK("waiting for expire %p name=%.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
+
+ status = autofs4_wait(sbi, dentry, NFY_NONE);
+ wait_for_completion(&ino->expire_complete);
+
+ DPRINTK("expire done status=%d", status);
+
+ if (d_unhashed(dentry))
+ return -EAGAIN;
+
+ return status;
+ }
+ spin_unlock(&sbi->fs_lock);
+
+ return 0;
+}
+
/* Perform an expiry operation */
int autofs4_expire_run(struct super_block *sb,
struct vfsmount *mnt,
@@ -390,7 +438,9 @@ int autofs4_expire_run(struct super_block *sb,
struct autofs_packet_expire __user *pkt_p)
{
struct autofs_packet_expire pkt;
+ struct autofs_info *ino;
struct dentry *dentry;
+ int ret = 0;
memset(&pkt,0,sizeof pkt);
@@ -406,9 +456,15 @@ int autofs4_expire_run(struct super_block *sb,
dput(dentry);
if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) )
- return -EFAULT;
+ ret = -EFAULT;
- return 0;
+ spin_lock(&sbi->fs_lock);
+ ino = autofs4_dentry_ino(dentry);
+ ino->flags &= ~AUTOFS_INF_EXPIRING;
+ complete_all(&ino->expire_complete);
+ spin_unlock(&sbi->fs_lock);
+
+ return ret;
}
/* Call repeatedly until it returns -EAGAIN, meaning there's nothing
@@ -423,7 +479,7 @@ int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
if (arg && get_user(do_now, arg))
return -EFAULT;
- if (sbi->type & AUTOFS_TYPE_DIRECT)
+ if (sbi->type & AUTOFS_TYPE_TRIGGER)
dentry = autofs4_expire_direct(sb, mnt, sbi, do_now);
else
dentry = autofs4_expire_indirect(sb, mnt, sbi, do_now);
@@ -433,9 +489,16 @@ int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
/* This is synchronous because it makes the daemon a
little easier */
- ino->flags |= AUTOFS_INF_EXPIRING;
ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
+
+ spin_lock(&sbi->fs_lock);
+ if (ino->flags & AUTOFS_INF_MOUNTPOINT) {
+ sb->s_root->d_mounted++;
+ ino->flags &= ~AUTOFS_INF_MOUNTPOINT;
+ }
ino->flags &= ~AUTOFS_INF_EXPIRING;
+ complete_all(&ino->expire_complete);
+ spin_unlock(&sbi->fs_lock);
dput(dentry);
}