static int remove_file(struct dentry *parent, char *name)
{
struct dentry *tmp;
int ret;
tmp = lookup_one_len(name, parent, strlen(name));
if (IS_ERR(tmp)) {
ret = PTR_ERR(tmp);
goto bail;
}
spin_lock(&tmp->d_lock);
if (simple_positive(tmp)) {
dget_dlock(tmp);
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
simple_unlink(d_inode(parent), tmp);
} else
spin_unlock(&tmp->d_lock);
ret = 0;
bail:
/*
* We don't expect clients to care about the return value, but
* it's there if they need it.
*/
return ret;
}
static struct dentry *autofs4_check_leaves(struct vfsmount *mnt,
struct dentry *parent,
unsigned long timeout,
int do_now)
{
struct dentry *this_parent = parent;
struct list_head *next;
DPRINTK("parent %p %.*s",
parent, (int)parent->d_name.len, parent->d_name.name);
spin_lock(&dcache_lock);
repeat:
next = this_parent->d_subdirs.next;
resume:
while (next != &this_parent->d_subdirs) {
struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
/* Negative dentry - give up */
if (!simple_positive(dentry)) {
next = next->next;
continue;
}
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
if (!list_empty(&dentry->d_subdirs)) {
this_parent = dentry;
goto repeat;
}
dentry = dget(dentry);
spin_unlock(&dcache_lock);
if (d_mountpoint(dentry)) {
/* Can we expire this guy */
if (!autofs4_can_expire(dentry, timeout, do_now))
goto cont;
/* Can we umount this guy */
if (autofs4_check_mount(mnt, dentry))
return dentry;
}
cont:
dput(dentry);
spin_lock(&dcache_lock);
next = next->next;
}
if (this_parent != parent) {
next = this_parent->d_u.d_child.next;
this_parent = this_parent->d_parent;
goto resume;
}
spin_unlock(&dcache_lock);
return NULL;
}
/*
* Calculate and dget next entry in top down tree traversal.
*/
static struct dentry *get_next_positive_dentry(struct dentry *prev,
struct dentry *root)
{
struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
struct list_head *next;
struct dentry *p, *ret;
if (prev == NULL)
return dget(root);
spin_lock(&sbi->lookup_lock);
relock:
p = prev;
spin_lock(&p->d_lock);
again:
next = p->d_subdirs.next;
if (next == &p->d_subdirs) {
while (1) {
struct dentry *parent;
if (p == root) {
spin_unlock(&p->d_lock);
spin_unlock(&sbi->lookup_lock);
dput(prev);
return NULL;
}
parent = p->d_parent;
if (!spin_trylock(&parent->d_lock)) {
spin_unlock(&p->d_lock);
cpu_relax();
goto relock;
}
spin_unlock(&p->d_lock);
next = p->d_child.next;
p = parent;
if (next != &parent->d_subdirs)
break;
}
}
ret = list_entry(next, struct dentry, d_child);
spin_lock_nested(&ret->d_lock, DENTRY_D_LOCK_NESTED);
/* Negative dentry - try next */
if (!simple_positive(ret)) {
spin_unlock(&p->d_lock);
lock_set_subclass(&ret->d_lock.dep_map, 0, _RET_IP_);
p = ret;
goto again;
}
dget_dlock(ret);
spin_unlock(&ret->d_lock);
spin_unlock(&p->d_lock);
spin_unlock(&sbi->lookup_lock);
dput(prev);
return ret;
}
/*
* Check a directory tree of mount points for busyness
* The tree is not busy iff no mountpoints are busy
*/
static int autofs4_tree_busy(struct vfsmount *mnt,
struct dentry *top,
unsigned long timeout,
int do_now)
{
struct autofs_info *top_ino = autofs4_dentry_ino(top);
struct dentry *p;
pr_debug("top %p %pd\n", top, top);
/* Negative dentry - give up */
if (!simple_positive(top))
return 1;
p = NULL;
while ((p = get_next_positive_dentry(p, top))) {
pr_debug("dentry %p %pd\n", p, p);
/*
* Is someone visiting anywhere in the subtree ?
* If there's no mount we need to check the usage
* count for the autofs dentry.
* If the fs is busy update the expiry counter.
*/
if (d_mountpoint(p)) {
if (autofs4_mount_busy(mnt, p)) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
} else {
struct autofs_info *ino = autofs4_dentry_ino(p);
unsigned int ino_count = atomic_read(&ino->count);
/* allow for dget above and top is already dgot */
if (p == top)
ino_count += 2;
else
ino_count++;
if (d_count(p) > ino_count) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
}
}
/* Timeout of a tree mount is ultimately determined by its top dentry */
if (!autofs4_can_expire(top, timeout, do_now))
return 1;
return 0;
}
/*
* Deal with the infamous "Busy inodes after umount ..." message.
*
* Clean up the dentry tree. This happens with autofs if the user
* space program goes away due to a SIGKILL, SIGSEGV etc.
*/
static void autofs4_force_release(struct autofs_sb_info *sbi)
{
struct dentry *this_parent = sbi->sb->s_root;
struct list_head *next;
if (!sbi->sb->s_root)
return;
spin_lock(&dcache_lock);
repeat:
next = this_parent->d_subdirs.next;
resume:
while (next != &this_parent->d_subdirs) {
struct dentry *dentry = list_entry(next, struct dentry, d_child);
/* Negative dentry - don`t care */
if (!simple_positive(dentry)) {
next = next->next;
continue;
}
if (!list_empty(&dentry->d_subdirs)) {
this_parent = dentry;
goto repeat;
}
next = next->next;
spin_unlock(&dcache_lock);
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
dput(dentry);
spin_lock(&dcache_lock);
}
if (this_parent != sbi->sb->s_root) {
struct dentry *dentry = this_parent;
next = this_parent->d_child.next;
this_parent = this_parent->d_parent;
spin_unlock(&dcache_lock);
DPRINTK("parent dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
dput(dentry);
spin_lock(&dcache_lock);
goto resume;
}
spin_unlock(&dcache_lock);
shrink_dcache_sb(sbi->sb);
return;
}
static int autofs4_tree_busy(struct vfsmount *mnt,
struct dentry *top,
unsigned long timeout,
int do_now)
{
struct autofs_info *top_ino = autofs4_dentry_ino(top);
struct dentry *p;
DPRINTK("top %p %.*s",
top, (int)top->d_name.len, top->d_name.name);
if (!simple_positive(top))
return 1;
p = NULL;
while ((p = get_next_positive_dentry(p, top))) {
DPRINTK("dentry %p %.*s",
p, (int) p->d_name.len, p->d_name.name);
if (d_mountpoint(p)) {
if (autofs4_mount_busy(mnt, p)) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
} else {
struct autofs_info *ino = autofs4_dentry_ino(p);
unsigned int ino_count = atomic_read(&ino->count);
d_invalidate(p);
if (p == top)
ino_count += 2;
else
ino_count++;
if (p->d_count > ino_count) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
}
}
if (!autofs4_can_expire(top, timeout, do_now))
return 1;
return 0;
}
static struct dentry *get_next_positive_subdir(struct dentry *prev,
struct dentry *root)
{
struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
struct list_head *next;
struct dentry *p, *q;
spin_lock(&sbi->lookup_lock);
if (prev == NULL) {
spin_lock(&root->d_lock);
prev = dget_dlock(root);
next = prev->d_subdirs.next;
p = prev;
goto start;
}
p = prev;
spin_lock(&p->d_lock);
again:
next = p->d_u.d_child.next;
start:
if (next == &root->d_subdirs) {
spin_unlock(&p->d_lock);
spin_unlock(&sbi->lookup_lock);
dput(prev);
return NULL;
}
q = list_entry(next, struct dentry, d_u.d_child);
spin_lock_nested(&q->d_lock, DENTRY_D_LOCK_NESTED);
if (!simple_positive(q)) {
spin_unlock(&p->d_lock);
lock_set_subclass(&q->d_lock.dep_map, 0, _RET_IP_);
p = q;
goto again;
}
dget_dlock(q);
spin_unlock(&q->d_lock);
spin_unlock(&p->d_lock);
spin_unlock(&sbi->lookup_lock);
dput(prev);
return q;
}
static void hypfs_remove(struct dentry *dentry)
{
struct dentry *parent;
parent = dentry->d_parent;
inode_lock(d_inode(parent));
if (simple_positive(dentry)) {
if (d_is_dir(dentry))
simple_rmdir(d_inode(parent), dentry);
else
simple_unlink(d_inode(parent), dentry);
}
d_delete(dentry);
dput(dentry);
inode_unlock(d_inode(parent));
}
/**
* securityfs_remove - removes a file or directory from the securityfs filesystem
*
* @dentry: a pointer to a the dentry of the file or directory to be removed.
*
* This function removes a file or directory in securityfs that was previously
* created with a call to another securityfs function (like
* securityfs_create_file() or variants thereof.)
*
* This function is required to be called in order for the file to be
* removed. No automatic cleanup of files will happen when a module is
* removed; you are responsible here.
*/
void securityfs_remove(struct dentry *dentry)
{
struct inode *dir;
if (!dentry || IS_ERR(dentry))
return;
dir = d_inode(dentry->d_parent);
inode_lock(dir);
if (simple_positive(dentry)) {
if (d_is_dir(dentry))
simple_rmdir(dir, dentry);
else
simple_unlink(dir, dentry);
dput(dentry);
}
inode_unlock(dir);
simple_release_fs(&mount, &mount_count);
}
/*
* Calculate and dget next entry in the subdirs list under root.
*/
static struct dentry *get_next_positive_subdir(struct dentry *prev,
struct dentry *root)
{
struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
struct list_head *next;
struct dentry *q;
spin_lock(&sbi->lookup_lock);
spin_lock(&root->d_lock);
if (prev)
next = prev->d_child.next;
else {
prev = dget_dlock(root);
next = prev->d_subdirs.next;
}
cont:
if (next == &root->d_subdirs) {
spin_unlock(&root->d_lock);
spin_unlock(&sbi->lookup_lock);
dput(prev);
return NULL;
}
q = list_entry(next, struct dentry, d_child);
spin_lock_nested(&q->d_lock, DENTRY_D_LOCK_NESTED);
/* Already gone or negative dentry (under construction) - try next */
if (!d_count(q) || !simple_positive(q)) {
spin_unlock(&q->d_lock);
next = q->d_child.next;
goto cont;
}
dget_dlock(q);
spin_unlock(&q->d_lock);
spin_unlock(&root->d_lock);
spin_unlock(&sbi->lookup_lock);
dput(prev);
return q;
}
/**
* securityfs_remove - removes a file or directory from the securityfs filesystem
*
* @dentry: a pointer to a the dentry of the file or directory to be removed.
*
* This function removes a file or directory in securityfs that was previously
* created with a call to another securityfs function (like
* securityfs_create_file() or variants thereof.)
*
* This function is required to be called in order for the file to be
* removed. No automatic cleanup of files will happen when a module is
* removed; you are responsible here.
*/
void securityfs_remove(struct dentry *dentry)
{
struct dentry *parent;
if (!dentry || IS_ERR(dentry))
return;
parent = dentry->d_parent;
if (!parent || d_really_is_negative(parent))
return;
inode_lock(d_inode(parent));
if (simple_positive(dentry)) {
if (d_is_dir(dentry))
simple_rmdir(d_inode(parent), dentry);
else
simple_unlink(d_inode(parent), dentry);
dput(dentry);
}
inode_unlock(d_inode(parent));
simple_release_fs(&mount, &mount_count);
}
loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence)
{
struct dentry *dentry = file->f_path.dentry;
mutex_lock(&dentry->d_inode->i_mutex);
switch (whence) {
case 1:
offset += file->f_pos;
case 0:
if (offset >= 0)
break;
default:
mutex_unlock(&dentry->d_inode->i_mutex);
return -EINVAL;
}
if (offset != file->f_pos) {
file->f_pos = offset;
if (file->f_pos >= 2) {
struct list_head *p;
struct dentry *cursor = file->private_data;
loff_t n = file->f_pos - 2;
spin_lock(&dentry->d_lock);
/* d_lock not required for cursor */
list_del(&cursor->d_u.d_child);
p = dentry->d_subdirs.next;
while (n && p != &dentry->d_subdirs) {
struct dentry *next;
next = list_entry(p, struct dentry, d_u.d_child);
spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
if (simple_positive(next))
n--;
spin_unlock(&next->d_lock);
p = p->next;
}
list_add_tail(&cursor->d_u.d_child, p);
spin_unlock(&dentry->d_lock);
}
}
static struct dentry *autofs4_check_leaves(struct vfsmount *mnt,
struct dentry *parent,
unsigned long timeout,
int do_now)
{
struct dentry *p;
DPRINTK("parent %p %.*s",
parent, (int)parent->d_name.len, parent->d_name.name);
spin_lock(&dcache_lock);
for (p = parent; p; p = next_dentry(p, parent)) {
/* Negative dentry - give up */
if (!simple_positive(p))
continue;
DPRINTK("dentry %p %.*s",
p, (int) p->d_name.len, p->d_name.name);
p = dget(p);
spin_unlock(&dcache_lock);
if (d_mountpoint(p)) {
/* Can we umount this guy */
if (autofs4_mount_busy(mnt, p))
goto cont;
/* Can we expire this guy */
if (autofs4_can_expire(p, timeout, do_now))
return p;
}
cont:
dput(p);
spin_lock(&dcache_lock);
}
spin_unlock(&dcache_lock);
return NULL;
}
/* Check a directory tree of mount points for busyness
* The tree is not busy iff no mountpoints are busy
* Return 1 if the tree is busy or 0 otherwise
*/
static int autofs4_check_tree(struct vfsmount *mnt,
struct dentry *top,
unsigned long timeout,
int do_now)
{
struct dentry *this_parent = top;
struct list_head *next;
DPRINTK("parent %p %.*s",
top, (int)top->d_name.len, top->d_name.name);
/* Negative dentry - give up */
if (!simple_positive(top))
return 0;
/* Timeout of a tree mount is determined by its top dentry */
if (!autofs4_can_expire(top, timeout, do_now))
return 0;
/* Is someone visiting anywhere in the tree ? */
if (may_umount_tree(mnt))
return 0;
spin_lock(&dcache_lock);
repeat:
next = this_parent->d_subdirs.next;
resume:
while (next != &this_parent->d_subdirs) {
struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
/* Negative dentry - give up */
if (!simple_positive(dentry)) {
next = next->next;
continue;
}
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
if (!simple_empty_nolock(dentry)) {
this_parent = dentry;
goto repeat;
}
dentry = dget(dentry);
spin_unlock(&dcache_lock);
if (d_mountpoint(dentry)) {
/* First busy => tree busy */
if (!autofs4_check_mount(mnt, dentry)) {
dput(dentry);
return 0;
}
}
dput(dentry);
spin_lock(&dcache_lock);
next = next->next;
}
if (this_parent != top) {
next = this_parent->d_u.d_child.next;
this_parent = this_parent->d_parent;
goto resume;
}
spin_unlock(&dcache_lock);
return 1;
}
/*
* Find an eligible tree to time-out
* A tree is eligible if :-
* - it is unused by any user process
* - 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 how)
{
unsigned long timeout;
struct dentry *root = sb->s_root;
struct dentry *expired = NULL;
struct list_head *next;
int do_now = how & AUTOFS_EXP_IMMEDIATE;
int exp_leaves = how & AUTOFS_EXP_LEAVES;
if ( !sbi->exp_timeout || !root )
return NULL;
now = jiffies;
timeout = sbi->exp_timeout;
spin_lock(&dcache_lock);
next = root->d_subdirs.next;
/* On exit from the loop expire is set to a dgot dentry
* to expire or it's NULL */
while ( next != &root->d_subdirs ) {
struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
/* Negative dentry - give up */
if ( !simple_positive(dentry) ) {
next = next->next;
continue;
}
dentry = dget(dentry);
spin_unlock(&dcache_lock);
/* Case 1: indirect mount or top level direct mount */
if (d_mountpoint(dentry)) {
DPRINTK("checking mountpoint %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
/* Can we expire this guy */
if (!autofs4_can_expire(dentry, timeout, do_now))
goto next;
/* Can we umount this guy */
if (autofs4_check_mount(mnt, dentry)) {
expired = dentry;
break;
}
goto next;
}
if ( simple_empty(dentry) )
goto next;
/* 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_check_tree(mnt, dentry, timeout, do_now)) {
struct autofs_info *inf = autofs4_dentry_ino(dentry);
/* Set this flag early to catch sys_chdir and the like */
inf->flags |= AUTOFS_INF_EXPIRING;
spin_unlock(&sbi->fs_lock);
expired = dentry;
break;
}
spin_unlock(&sbi->fs_lock);
/* Case 3: direct mount, expire individual leaves */
} else {
expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
if (expired) {
dput(dentry);
break;
}
}
next:
dput(dentry);
spin_lock(&dcache_lock);
next = next->next;
}
if ( expired ) {
DPRINTK("returning %p %.*s",
expired, (int)expired->d_name.len, expired->d_name.name);
spin_lock(&dcache_lock);
list_del(&expired->d_parent->d_subdirs);
list_add(&expired->d_parent->d_subdirs, &expired->d_u.d_child);
spin_unlock(&dcache_lock);
return expired;
}
spin_unlock(&dcache_lock);
return NULL;
}
/* Check a directory tree of mount points for busyness
* The tree is not busy iff no mountpoints are busy
*/
static int autofs4_tree_busy(struct vfsmount *mnt,
struct dentry *top,
unsigned long timeout,
int do_now)
{
struct autofs_info *top_ino = autofs4_dentry_ino(top);
struct dentry *p;
DPRINTK("top %p %.*s",
top, (int)top->d_name.len, top->d_name.name);
/* Negative dentry - give up */
if (!simple_positive(top))
return 1;
spin_lock(&dcache_lock);
for (p = top; p; p = next_dentry(p, top)) {
/* Negative dentry - give up */
if (!simple_positive(p))
continue;
DPRINTK("dentry %p %.*s",
p, (int) p->d_name.len, p->d_name.name);
p = dget(p);
spin_unlock(&dcache_lock);
/*
* Is someone visiting anywhere in the subtree ?
* If there's no mount we need to check the usage
* count for the autofs dentry.
* If the fs is busy update the expiry counter.
*/
if (d_mountpoint(p)) {
if (autofs4_mount_busy(mnt, p)) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
} else {
struct autofs_info *ino = autofs4_dentry_ino(p);
unsigned int ino_count = atomic_read(&ino->count);
/* allow for dget above and top is already dgot */
if (p == top)
ino_count += 2;
else
ino_count++;
if (atomic_read(&p->d_count) > ino_count) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
}
dput(p);
spin_lock(&dcache_lock);
}
spin_unlock(&dcache_lock);
/* Timeout of a tree mount is ultimately determined by its top dentry */
if (!autofs4_can_expire(top, timeout, do_now))
return 1;
return 0;
}
/*
* Find an eligible tree to time-out
* A tree is eligible if :-
* - it is unused by any user process
* - it has been unused for exp_timeout time
*/
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;
struct dentry *expired = NULL;
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;
now = jiffies;
timeout = sbi->exp_timeout;
spin_lock(&dcache_lock);
next = root->d_subdirs.next;
/* On exit from the loop expire is set to a dgot dentry
* to expire or it's NULL */
while ( next != &root->d_subdirs ) {
struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
/* Negative dentry - give up */
if (!simple_positive(dentry)) {
next = next->next;
continue;
}
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).
* (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);
/* 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;
/* Can we expire this guy */
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 (atomic_read(&dentry->d_count) > 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 (atomic_read(&dentry->d_count) > ino_count)
goto next;
expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
if (expired) {
dput(dentry);
goto found;
}
}
next:
spin_unlock(&sbi->fs_lock);
dput(dentry);
spin_lock(&dcache_lock);
next = next->next;
}
spin_unlock(&dcache_lock);
return NULL;
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;
}
/* Check a directory tree of mount points for busyness
* The tree is not busy iff no mountpoints are busy
*/
static int autofs4_tree_busy(struct vfsmount *mnt,
struct dentry *top,
unsigned long timeout,
int do_now)
{
struct autofs_info *top_ino = autofs4_dentry_ino(top);
struct dentry *p;
DPRINTK("top %p %.*s",
top, (int)top->d_name.len, top->d_name.name);
/* Negative dentry - give up */
if (!simple_positive(top))
return 1;
p = NULL;
while ((p = get_next_positive_dentry(p, top))) {
DPRINTK("dentry %p %.*s",
p, (int) p->d_name.len, p->d_name.name);
/*
* Is someone visiting anywhere in the subtree ?
* If there's no mount we need to check the usage
* count for the autofs dentry.
* If the fs is busy update the expiry counter.
*/
if (d_mountpoint(p)) {
if (autofs4_mount_busy(mnt, p)) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
} else {
struct autofs_info *ino = autofs4_dentry_ino(p);
unsigned int ino_count = atomic_read(&ino->count);
/*
* Clean stale dentries below that have not been
* invalidated after a mount fail during lookup
*/
d_invalidate(p);
/* allow for dget above and top is already dgot */
if (p == top)
ino_count += 2;
else
ino_count++;
if (p->d_count > ino_count) {
top_ino->last_used = jiffies;
dput(p);
return 1;
}
}
}
/* Timeout of a tree mount is ultimately determined by its top dentry */
if (!autofs4_can_expire(top, timeout, do_now))
return 1;
return 0;
}
