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Diffstat (limited to 'fs/autofs4/expire.c')
-rw-r--r--fs/autofs4/expire.c115
1 files changed, 32 insertions, 83 deletions
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index e93557db8..98a7a0e6c 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -14,102 +14,39 @@
#include "autofs_i.h"
/*
- * Determine if a dentry tree is in use. This is much the
- * same as the standard is_root_busy() function, except
- * that :-
- * - the extra dentry reference in autofs dentries is not
- * considered to be busy
- * - mountpoints within the tree are not busy
- * - it traverses across mountpoints
- * XXX doesn't consider children of covered dentries at mountpoints
+ * Determine if a subtree of the namespace is busy.
*/
-static int is_tree_busy(struct dentry *root)
+static int is_tree_busy(struct vfsmount *mnt)
{
- struct dentry *this_parent;
+ struct vfsmount *this_parent = mnt;
struct list_head *next;
int count;
- root = root->d_mounts;
-
- count = root->d_count;
- this_parent = root;
-
- DPRINTK(("is_tree_busy: starting at %.*s/%.*s, d_count=%d\n",
- root->d_covers->d_parent->d_name.len,
- root->d_covers->d_parent->d_name.name,
- root->d_name.len, root->d_name.name,
- root->d_count));
-
- /* Ignore autofs's extra reference */
- if (is_autofs4_dentry(root)) {
- DPRINTK(("is_tree_busy: autofs\n"));
- count--;
- }
-
- /* Mountpoints don't count (either mountee or mounter) */
- if (d_mountpoint(root) ||
- root != root->d_covers) {
- DPRINTK(("is_tree_busy: mountpoint\n"));
- count--;
- }
-
+ count = atomic_read(&mnt->mnt_count);
repeat:
- next = this_parent->d_mounts->d_subdirs.next;
+ next = this_parent->mnt_mounts.next;
resume:
- while (next != &this_parent->d_mounts->d_subdirs) {
- int adj = 0;
+ while (next != &this_parent->mnt_mounts) {
struct list_head *tmp = next;
- struct dentry *dentry = list_entry(tmp, struct dentry,
- d_child);
-
+ struct vfsmount *p = list_entry(tmp, struct vfsmount,
+ mnt_child);
next = tmp->next;
-
- dentry = dentry->d_mounts;
-
- DPRINTK(("is_tree_busy: considering %.*s/%.*s, d_count=%d, count=%d\n",
- this_parent->d_name.len,
- this_parent->d_name.name,
- dentry->d_covers->d_name.len,
- dentry->d_covers->d_name.name,
- dentry->d_count, count));
-
/* Decrement count for unused children */
- count += (dentry->d_count - 1);
-
- /* Mountpoints don't count (either mountee or mounter) */
- if (d_mountpoint(dentry) ||
- dentry != dentry->d_covers) {
- DPRINTK(("is_tree_busy: mountpoint dentry=%p covers=%p mounts=%p\n",
- dentry, dentry->d_covers, dentry->d_mounts));
- adj++;
- }
-
- /* Ignore autofs's extra reference */
- if (is_autofs4_dentry(dentry)) {
- DPRINTK(("is_tree_busy: autofs\n"));
- adj++;
- }
-
- count -= adj;
-
- if (!list_empty(&dentry->d_mounts->d_subdirs)) {
- this_parent = dentry->d_mounts;
+ count += atomic_read(&p->mnt_count) - 1;
+ if (!list_empty(&p->mnt_mounts)) {
+ this_parent = p;
goto repeat;
}
-
/* root is busy if any leaf is busy */
- if (dentry->d_count != adj) {
- DPRINTK(("is_tree_busy: busy leaf (d_count=%d adj=%d)\n",
- dentry->d_count, adj));
+ if (atomic_read(&p->mnt_count) > 1)
return 1;
- }
}
/*
* All done at this level ... ascend and resume the search.
*/
- if (this_parent != root) {
- next = this_parent->d_covers->d_child.next;
- this_parent = this_parent->d_covers->d_parent;
+ if (this_parent != mnt) {
+ next = this_parent->mnt_child.next;
+ this_parent = this_parent->mnt_parent;
goto resume;
}
@@ -124,6 +61,7 @@ resume:
* - it has been unused for exp_timeout time
*/
static struct dentry *autofs4_expire(struct super_block *sb,
+ struct vfsmount *mnt,
struct autofs_sb_info *sbi,
int do_now)
{
@@ -131,6 +69,8 @@ static struct dentry *autofs4_expire(struct super_block *sb,
unsigned long timeout;
struct dentry *root = sb->s_root;
struct list_head *tmp;
+ struct dentry *d;
+ struct vfsmount *p;
if (!sbi->exp_timeout || !root)
return NULL;
@@ -168,8 +108,14 @@ static struct dentry *autofs4_expire(struct super_block *sb,
attempts if expire fails the first time */
ino->last_used = now;
}
-
- if (!is_tree_busy(dentry)) {
+ p = mntget(mnt);
+ d = dget(dentry);
+ while(d_mountpoint(d) && follow_down(&p, &d))
+ ;
+
+ if (!is_tree_busy(p)) {
+ dput(d);
+ mntput(p);
DPRINTK(("autofs_expire: returning %p %.*s\n",
dentry, dentry->d_name.len, dentry->d_name.name));
/* Start from here next time */
@@ -177,6 +123,8 @@ static struct dentry *autofs4_expire(struct super_block *sb,
list_add(&root->d_subdirs, &dentry->d_child);
return dentry;
}
+ dput(d);
+ mntput(p);
}
return NULL;
@@ -184,6 +132,7 @@ static struct dentry *autofs4_expire(struct super_block *sb,
/* Perform an expiry operation */
int autofs4_expire_run(struct super_block *sb,
+ struct vfsmount *mnt,
struct autofs_sb_info *sbi,
struct autofs_packet_expire *pkt_p)
{
@@ -195,7 +144,7 @@ int autofs4_expire_run(struct super_block *sb,
pkt.hdr.proto_version = sbi->version;
pkt.hdr.type = autofs_ptype_expire;
- if ((dentry = autofs4_expire(sb, sbi, 0)) == NULL)
+ if ((dentry = autofs4_expire(sb, mnt, sbi, 0)) == NULL)
return -EAGAIN;
pkt.len = dentry->d_name.len;
@@ -210,7 +159,7 @@ int autofs4_expire_run(struct super_block *sb,
/* Call repeatedly until it returns -EAGAIN, meaning there's nothing
more to be done */
-int autofs4_expire_multi(struct super_block *sb,
+int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
struct autofs_sb_info *sbi, int *arg)
{
struct dentry *dentry;
@@ -220,7 +169,7 @@ int autofs4_expire_multi(struct super_block *sb,
if (arg && get_user(do_now, arg))
return -EFAULT;
- if ((dentry = autofs4_expire(sb, sbi, do_now)) != NULL) {
+ if ((dentry = autofs4_expire(sb, mnt, sbi, do_now)) != NULL) {
struct autofs_info *de_info = autofs4_dentry_ino(dentry);
/* This is synchronous because it makes the daemon a
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 02:22:01 +0000