/* Check a mount point for busyness return 1 if not busy, otherwise */
static int autofs4_check_mount(struct vfsmount *mnt, struct dentry *dentry)
{
int status = 0;
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
mntget(mnt);
dget(dentry);
if (!autofs4_follow_mount(&mnt, &dentry))
goto done;
/* This is an autofs submount, we can't expire it */
if (is_autofs4_dentry(dentry))
goto done;
/* The big question */
if (may_umount_tree(mnt) == 0)
status = 1;
done:
DPRINTK("returning = %d", status);
mntput(mnt);
dput(dentry);
return status;
}
/* Check a mount point for busyness */
static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)
{
struct dentry *top = dentry;
struct path path = {.mnt = mnt, .dentry = dentry};
int status = 1;
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
path_get(&path);
if (!follow_down_one(&path))
goto done;
if (is_autofs4_dentry(path.dentry)) {
struct autofs_sb_info *sbi = autofs4_sbi(path.dentry->d_sb);
/* This is an autofs submount, we can't expire it */
if (autofs_type_indirect(sbi->type))
goto done;
}
/* Update the expiry counter if fs is busy */
if (!may_umount_tree(path.mnt)) {
struct autofs_info *ino = autofs4_dentry_ino(top);
ino->last_used = jiffies;
goto done;
}
status = 0;
done:
DPRINTK("returning = %d", status);
path_put(&path);
return status;
}
/* Check a mount point for busyness */
static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)
{
struct dentry *top = dentry;
int status = 1;
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
mntget(mnt);
dget(dentry);
if (!autofs4_follow_mount(&mnt, &dentry))
goto done;
/* This is an autofs submount, we can't expire it */
if (is_autofs4_dentry(dentry))
goto done;
/* Update the expiry counter if fs is busy */
if (!may_umount_tree(mnt)) {
struct autofs_info *ino = autofs4_dentry_ino(top);
ino->last_used = jiffies;
goto done;
}
status = 0;
done:
DPRINTK("returning = %d", status);
mntput(mnt);
dput(dentry);
return status;
}
/* Check a mount point for busyness */
static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)
{
struct dentry *top = dentry;
int status = 1;
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
mntget(mnt);
dget(dentry);
if (!follow_down(&mnt, &dentry))
goto done;
if (is_autofs4_dentry(dentry)) {
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
/* This is an autofs submount, we can't expire it */
if (autofs_type_indirect(sbi->type))
goto done;
/*
* Otherwise it's an offset mount and we need to check
* if we can umount its mount, if there is one.
*/
if (!d_mountpoint(dentry))
goto done;
}
/* Update the expiry counter if fs is busy */
if (!may_umount_tree(mnt)) {
struct autofs_info *ino = autofs4_dentry_ino(top);
ino->last_used = jiffies;
goto done;
}
status = 0;
done:
DPRINTK("returning = %d", status);
dput(dentry);
mntput(mnt);
return status;
}
/* Check dentry tree for busyness. If a dentry appears to be busy
because it is a mountpoint, check to see if the mounted
filesystem is busy. */
static int is_tree_busy(struct vfsmount *topmnt, struct dentry *top)
{
struct dentry *this_parent;
struct list_head *next;
int count;
count = atomic_read(&top->d_count);
DPRINTK(("is_tree_busy: top=%p initial count=%d\n",
top, count));
this_parent = top;
if (is_autofs4_dentry(top)) {
count--;
DPRINTK(("is_tree_busy: autofs; count=%d\n", count));
}
if (d_mountpoint(top))
count -= check_vfsmnt(topmnt, top);
repeat:
next = this_parent->d_subdirs.next;
resume:
while (next != &this_parent->d_subdirs) {
int adj = 0;
struct dentry *dentry = list_entry(next, struct dentry,
d_child);
next = next->next;
count += atomic_read(&dentry->d_count) - 1;
if (d_mountpoint(dentry))
adj += check_vfsmnt(topmnt, dentry);
if (is_autofs4_dentry(dentry)) {
adj++;
DPRINTK(("is_tree_busy: autofs; adj=%d\n",
adj));
}
count -= adj;
if (!list_empty(&dentry->d_subdirs)) {
this_parent = dentry;
goto repeat;
}
if (atomic_read(&dentry->d_count) != adj) {
DPRINTK(("is_tree_busy: busy leaf (d_count=%d adj=%d)\n",
atomic_read(&dentry->d_count), adj));
return 1;
}
}
/* All done at this level ... ascend and resume the search. */
if (this_parent != top) {
next = this_parent->d_child.next;
this_parent = this_parent->d_parent;
goto resume;
}
DPRINTK(("is_tree_busy: count=%d\n", count));
return count != 0; /* remaining users? */
}