/* Check if a dentry can be expired */
static inline int autofs4_can_expire(struct dentry *dentry,
unsigned long timeout, int do_now)
{
struct autofs_info *ino = autofs4_dentry_ino(dentry);
/* dentry in the process of being deleted */
if (ino == NULL)
return 0;
if (!do_now) {
/* Too young to die */
if (!timeout || time_after(ino->last_used + timeout, now))
return 0;
/* update last_used here :-
- obviously makes sense if it is in use now
- less obviously, prevents rapid-fire expire
attempts if expire fails the first time */
ino->last_used = now;
}
return 1;
}
/*
* Check a direct mount point for busyness.
* Direct mounts have similar expiry semantics to tree mounts.
* The tree is not busy iff no mountpoints are busy and there are no
* autofs submounts.
*/
static int autofs4_direct_busy(struct vfsmount *mnt,
struct dentry *top,
unsigned long timeout,
int do_now)
{
DPRINTK("top %p %.*s",
top, (int) top->d_name.len, top->d_name.name);
/* If it's busy update the expiry counters */
if (!may_umount_tree(mnt)) {
struct autofs_info *ino = autofs4_dentry_ino(top);
if (ino)
ino->last_used = jiffies;
return 1;
}
/* Timeout of a direct mount is determined by its top dentry */
if (!autofs4_can_expire(top, timeout, do_now))
return 1;
return 0;
}
int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
struct autofs_sb_info *sbi, int when)
{
struct dentry *dentry;
int ret = -EAGAIN;
if (autofs_type_trigger(sbi->type))
dentry = autofs4_expire_direct(sb, mnt, sbi, when);
else
dentry = autofs4_expire_indirect(sb, mnt, sbi, when);
if (dentry) {
struct autofs_info *ino = autofs4_dentry_ino(dentry);
/* This is synchronous because it makes the daemon a
little easier */
ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
spin_lock(&sbi->fs_lock);
ino->flags &= ~AUTOFS_INF_EXPIRING;
spin_lock(&dentry->d_lock);
if (ret)
__managed_dentry_clear_transit(dentry);
else {
if ((IS_ROOT(dentry) ||
(autofs_type_indirect(sbi->type) &&
IS_ROOT(dentry->d_parent))) &&
!(dentry->d_flags & DCACHE_NEED_AUTOMOUNT))
__managed_dentry_set_automount(dentry);
}
spin_unlock(&dentry->d_lock);
complete_all(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
dput(dentry);
}
return ret;
}
static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
struct inode *inode;
lock_kernel();
if ( !autofs4_oz_mode(sbi) ) {
unlock_kernel();
return -EACCES;
}
DPRINTK(("autofs_dir_mkdir: dentry %p, creating %.*s\n",
dentry, dentry->d_name.len, dentry->d_name.name));
ino = autofs4_init_ino(ino, sbi, S_IFDIR | 0555);
if (ino == NULL) {
unlock_kernel();
return -ENOSPC;
}
inode = autofs4_get_inode(dir->i_sb, ino);
d_instantiate(dentry, inode);
if (dir == dir->i_sb->s_root->d_inode)
dentry->d_op = &autofs4_root_dentry_operations;
else
dentry->d_op = &autofs4_dentry_operations;
dentry->d_fsdata = ino;
ino->dentry = dget(dentry);
ino->inode = inode;
dir->i_nlink++;
dir->i_mtime = CURRENT_TIME;
unlock_kernel();
return 0;
}
/* Call repeatedly until it returns -EAGAIN, meaning there's nothing
more to be done */
int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
struct autofs_sb_info *sbi, int __user *arg)
{
struct dentry *dentry;
int ret = -EAGAIN;
int do_now = 0;
if (arg && get_user(do_now, arg))
return -EFAULT;
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
little easier */
de_info->flags |= AUTOFS_INF_EXPIRING;
ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
de_info->flags &= ~AUTOFS_INF_EXPIRING;
dput(dentry);
}
return ret;
}
/*
* Return the uid and gid of the last request for the mount
*
* When reconstructing an autofs mount tree with active mounts
* we need to re-connect to mounts that may have used the original
* process uid and gid (or string variations of them) for mount
* lookups within the map entry.
*/
static int autofs_dev_ioctl_requester(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct autofs_info *ino;
struct path path;
dev_t devid;
int err = -ENOENT;
if (param->size <= sizeof(*param)) {
err = -EINVAL;
goto out;
}
devid = sbi->sb->s_dev;
param->requester.uid = param->requester.gid = -1;
err = find_autofs_mount(param->path, &path, test_by_dev, &devid);
if (err)
goto out;
ino = autofs4_dentry_ino(path.dentry);
if (ino) {
err = 0;
autofs4_expire_wait(&path, 0);
spin_lock(&sbi->fs_lock);
param->requester.uid =
from_kuid_munged(current_user_ns(), ino->uid);
param->requester.gid =
from_kgid_munged(current_user_ns(), ino->gid);
spin_unlock(&sbi->fs_lock);
}
path_put(&path);
out:
return err;
}
/* Perform an expiry operation */
int autofs4_expire_run(struct super_block *sb,
struct vfsmount *mnt,
struct autofs_sb_info *sbi,
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));
pkt.hdr.proto_version = sbi->version;
pkt.hdr.type = autofs_ptype_expire;
dentry = autofs4_expire_indirect(sb, mnt, sbi, 0);
if (!dentry)
return -EAGAIN;
pkt.len = dentry->d_name.len;
memcpy(pkt.name, dentry->d_name.name, pkt.len);
pkt.name[pkt.len] = '\0';
dput(dentry);
if (copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)))
ret = -EFAULT;
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
/* avoid rapid-fire expire attempts if expiry fails */
ino->last_used = now;
ino->flags &= ~(AUTOFS_INF_EXPIRING|AUTOFS_INF_WANT_EXPIRE);
complete_all(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
return ret;
}
/* Perform an expiry operation */
int autofs4_expire_run(struct super_block *sb,
struct vfsmount *mnt,
struct autofs_sb_info *sbi,
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);
pkt.hdr.proto_version = sbi->version;
pkt.hdr.type = autofs_ptype_expire;
if ((dentry = autofs4_expire_indirect(sb, mnt, sbi, 0)) == NULL)
return -EAGAIN;
pkt.len = dentry->d_name.len;
memcpy(pkt.name, dentry->d_name.name, pkt.len);
pkt.name[pkt.len] = '\0';
dput(dentry);
if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) )
ret = -EFAULT;
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
ino->flags &= ~AUTOFS_INF_EXPIRING;
if (!d_unhashed(dentry))
managed_dentry_clear_transit(dentry);
complete_all(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
return ret;
}
/* 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;
pr_debug("dentry %p %pd\n", dentry, dentry);
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;
ino = autofs4_dentry_ino(top);
ino->last_used = jiffies;
goto done;
}
status = 0;
done:
pr_debug("returning = %d\n", status);
path_put(&path);
return status;
}
/*
* 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;
}
/*
* 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 *dentry;
struct dentry *expired;
struct dentry *found;
struct autofs_info *ino;
if (!root)
return NULL;
now = jiffies;
timeout = sbi->exp_timeout;
dentry = NULL;
while ((dentry = get_next_positive_subdir(dentry, root))) {
int flags = how;
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
if (ino->flags & AUTOFS_INF_WANT_EXPIRE) {
spin_unlock(&sbi->fs_lock);
continue;
}
spin_unlock(&sbi->fs_lock);
expired = should_expire(dentry, mnt, timeout, flags);
if (!expired)
continue;
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(expired);
ino->flags |= AUTOFS_INF_WANT_EXPIRE;
spin_unlock(&sbi->fs_lock);
synchronize_rcu();
/* Make sure a reference is not taken on found if
* things have changed.
*/
flags &= ~AUTOFS_EXP_LEAVES;
found = should_expire(expired, mnt, timeout, how);
if (!found || found != expired)
/* Something has changed, continue */
goto next;
if (expired != dentry)
dput(dentry);
spin_lock(&sbi->fs_lock);
goto found;
next:
spin_lock(&sbi->fs_lock);
ino->flags &= ~AUTOFS_INF_WANT_EXPIRE;
spin_unlock(&sbi->fs_lock);
if (expired != dentry)
dput(expired);
}
return NULL;
found:
pr_debug("returning %p %pd\n", expired, expired);
ino->flags |= AUTOFS_INF_EXPIRING;
init_completion(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
return expired;
}
/* 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)) {
pr_debug("checking mountpoint %p %pd\n", dentry, dentry);
/* 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 (d_really_is_positive(dentry) && d_is_symlink(dentry)) {
pr_debug("checking symlink %p %pd\n", dentry, dentry);
/*
* 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;
}
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 *dentry;
struct dentry *expired = NULL;
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;
dentry = NULL;
while ((dentry = get_next_positive_subdir(dentry, root))) {
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
if (ino->flags & AUTOFS_INF_PENDING)
goto next;
if (d_mountpoint(dentry)) {
DPRINTK("checking mountpoint %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
ino_count = atomic_read(&ino->count) + 2;
if (dentry->d_count > ino_count)
goto next;
if (autofs4_mount_busy(mnt, dentry))
goto next;
if (autofs4_can_expire(dentry, timeout, do_now)) {
expired = dentry;
goto found;
}
goto next;
}
if (simple_empty(dentry))
goto next;
if (!exp_leaves) {
ino_count = atomic_read(&ino->count) + 1;
if (dentry->d_count > ino_count)
goto next;
if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
expired = dentry;
goto found;
}
} else {
ino_count = atomic_read(&ino->count) + 1;
if (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);
}
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(&sbi->lookup_lock);
spin_lock(&expired->d_parent->d_lock);
spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED);
list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child);
spin_unlock(&expired->d_lock);
spin_unlock(&expired->d_parent->d_lock);
spin_unlock(&sbi->lookup_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;
}
/*
* 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 *dentry;
struct dentry *expired = NULL;
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;
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);
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 2;
if (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 (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 (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);
}
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(&sbi->lookup_lock);
spin_lock(&expired->d_parent->d_lock);
spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED);
list_move(&expired->d_parent->d_subdirs, &expired->d_child);
spin_unlock(&expired->d_lock);
spin_unlock(&expired->d_parent->d_lock);
spin_unlock(&sbi->lookup_lock);
return expired;
}
static int try_to_fill_dentry(struct dentry *dentry,
struct super_block *sb,
struct autofs_sb_info *sbi, int flags)
{
struct autofs_info *de_info = autofs4_dentry_ino(dentry);
int status = 0;
/* Block on any pending expiry here; invalidate the dentry
when expiration is done to trigger mount request with a new
dentry */
if (de_info && (de_info->flags & AUTOFS_INF_EXPIRING)) {
DPRINTK("waiting for expire %p name=%.*s",
dentry, dentry->d_name.len, dentry->d_name.name);
status = autofs4_wait(sbi, dentry, NFY_NONE);
DPRINTK("expire done status=%d", status);
return 0;
}
DPRINTK("dentry=%p %.*s ino=%p",
dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
/* Wait for a pending mount, triggering one if there isn't one already */
if (dentry->d_inode == NULL) {
DPRINTK("waiting for mount name=%.*s",
dentry->d_name.len, dentry->d_name.name);
status = autofs4_wait(sbi, dentry, NFY_MOUNT);
DPRINTK("mount done status=%d", status);
if (status && dentry->d_inode)
return 0; /* Try to get the kernel to invalidate this dentry */
/* Turn this into a real negative dentry? */
if (status == -ENOENT) {
dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT;
spin_lock(&dentry->d_lock);
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
return 1;
} else if (status) {
/* Return a negative dentry, but leave it "pending" */
return 1;
}
/* Trigger mount for path component or follow link */
} else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
current->link_count) {
DPRINTK("waiting for mount name=%.*s",
dentry->d_name.len, dentry->d_name.name);
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
status = autofs4_wait(sbi, dentry, NFY_MOUNT);
DPRINTK("mount done status=%d", status);
if (status) {
spin_lock(&dentry->d_lock);
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
return 0;
}
}
/* We don't update the usages for the autofs daemon itself, this
is necessary for recursive autofs mounts */
if (!autofs4_oz_mode(sbi))
autofs4_update_usage(dentry);
spin_lock(&dentry->d_lock);
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
return 1;
}
/* 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
*/
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;
}
/*
* 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 do_now)
{
unsigned long now = jiffies;
unsigned long timeout;
struct dentry *root = sb->s_root;
struct list_head *tmp;
if (!sbi->exp_timeout || !root)
return NULL;
timeout = sbi->exp_timeout;
spin_lock(&dcache_lock);
for(tmp = root->d_subdirs.next;
tmp != &root->d_subdirs;
tmp = tmp->next) {
struct autofs_info *ino;
struct dentry *dentry = list_entry(tmp, struct dentry, d_child);
if (dentry->d_inode == NULL)
continue;
ino = autofs4_dentry_ino(dentry);
if (ino == NULL) {
/* dentry in the process of being deleted */
continue;
}
/* No point expiring a pending mount */
if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
continue;
if (!do_now) {
/* Too young to die */
if (time_after(ino->last_used + timeout, now))
continue;
/* update last_used here :-
- obviously makes sense if it is in use now
- less obviously, prevents rapid-fire expire
attempts if expire fails the first time */
ino->last_used = now;
}
if (!is_tree_busy(mnt, dentry)) {
DPRINTK(("autofs_expire: returning %p %.*s\n",
dentry, (int)dentry->d_name.len, dentry->d_name.name));
/* Start from here next time */
list_del(&root->d_subdirs);
list_add(&root->d_subdirs, &dentry->d_child);
dget(dentry);
spin_unlock(&dcache_lock);
return dentry;
}
}
spin_unlock(&dcache_lock);
return NULL;
}
static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct autofs_info *ino = autofs4_dentry_ino(dentry);
nd_set_link(nd, (char *)ino->u.symlink);
return NULL;
}
int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
enum autofs_notify notify)
{
struct autofs_wait_queue *wq;
struct qstr qstr;
char *name;
int status, ret, type;
/* In catatonic mode, we don't wait for nobody */
if (sbi->catatonic)
return -ENOENT;
if (!dentry->d_inode) {
/*
* A wait for a negative dentry is invalid for certain
* cases. A direct or offset mount "always" has its mount
* point directory created and so the request dentry must
* be positive or the map key doesn't exist. The situation
* is very similar for indirect mounts except only dentrys
* in the root of the autofs file system may be negative.
*/
if (autofs_type_trigger(sbi->type))
return -ENOENT;
else if (!IS_ROOT(dentry->d_parent))
return -ENOENT;
}
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
/* If this is a direct mount request create a dummy name */
if (IS_ROOT(dentry) && autofs_type_trigger(sbi->type))
qstr.len = sprintf(name, "%p", dentry);
else {
qstr.len = autofs4_getpath(sbi, dentry, &name);
if (!qstr.len) {
kfree(name);
return -ENOENT;
}
}
qstr.name = name;
qstr.hash = full_name_hash(name, qstr.len);
if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(qstr.name);
return -EINTR;
}
ret = validate_request(&wq, sbi, &qstr, dentry, notify);
if (ret <= 0) {
if (ret == 0)
mutex_unlock(&sbi->wq_mutex);
kfree(qstr.name);
return ret;
}
if (!wq) {
/* Create a new wait queue */
wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
if (!wq) {
kfree(qstr.name);
mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->wait_queue_token = autofs4_next_wait_queue;
if (++autofs4_next_wait_queue == 0)
autofs4_next_wait_queue = 1;
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
memcpy(&wq->name, &qstr, sizeof(struct qstr));
wq->dev = autofs4_get_dev(sbi);
wq->ino = autofs4_get_ino(sbi);
wq->uid = current_uid();
wq->gid = current_gid();
wq->pid = current->pid;
wq->tgid = current->tgid;
wq->status = -EINTR; /* Status return if interrupted */
wq->wait_ctr = 2;
mutex_unlock(&sbi->wq_mutex);
if (sbi->version < 5) {
if (notify == NFY_MOUNT)
type = autofs_ptype_missing;
else
type = autofs_ptype_expire_multi;
} else {
if (notify == NFY_MOUNT)
type = autofs_type_trigger(sbi->type) ?
autofs_ptype_missing_direct :
autofs_ptype_missing_indirect;
else
type = autofs_type_trigger(sbi->type) ?
autofs_ptype_expire_direct :
autofs_ptype_expire_indirect;
}
DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
(unsigned long) wq->wait_queue_token, wq->name.len,
wq->name.name, notify);
/* autofs4_notify_daemon() may block */
autofs4_notify_daemon(sbi, wq, type);
} else {
wq->wait_ctr++;
mutex_unlock(&sbi->wq_mutex);
kfree(qstr.name);
DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
(unsigned long) wq->wait_queue_token, wq->name.len,
wq->name.name, notify);
}
/*
* wq->name.name is NULL iff the lock is already released
* or the mount has been made catatonic.
*/
if (wq->name.name) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
oldset = current->blocked;
siginitsetinv(¤t->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
wait_event_interruptible(wq->queue, wq->name.name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
} else {
DPRINTK("skipped sleeping");
}
status = wq->status;
/*
* For direct and offset mounts we need to track the requester's
* uid and gid in the dentry info struct. This is so it can be
* supplied, on request, by the misc device ioctl interface.
* This is needed during daemon resatart when reconnecting
* to existing, active, autofs mounts. The uid and gid (and
* related string values) may be used for macro substitution
* in autofs mount maps.
*/
if (!status) {
struct autofs_info *ino;
struct dentry *de = NULL;
/* direct mount or browsable map */
ino = autofs4_dentry_ino(dentry);
if (!ino) {
/* If not lookup actual dentry used */
de = d_lookup(dentry->d_parent, &dentry->d_name);
if (de)
ino = autofs4_dentry_ino(de);
}
/* Set mount requester */
if (ino) {
spin_lock(&sbi->fs_lock);
ino->uid = wq->uid;
ino->gid = wq->gid;
spin_unlock(&sbi->fs_lock);
}
if (de)
dput(de);
}
/* Are we the last process to need status? */
mutex_lock(&sbi->wq_mutex);
if (!--wq->wait_ctr)
kfree(wq);
mutex_unlock(&sbi->wq_mutex);
return status;
}
/*
* Check if we have a valid request.
* Returns
* 1 if the request should continue.
* In this case we can return an autofs_wait_queue entry if one is
* found or NULL to idicate a new wait needs to be created.
* 0 or a negative errno if the request shouldn't continue.
*/
static int validate_request(struct autofs_wait_queue **wait,
struct autofs_sb_info *sbi,
struct qstr *qstr,
struct dentry*dentry, enum autofs_notify notify)
{
struct autofs_wait_queue *wq;
struct autofs_info *ino;
/* Wait in progress, continue; */
wq = autofs4_find_wait(sbi, qstr);
if (wq) {
*wait = wq;
return 1;
}
*wait = NULL;
/* If we don't yet have any info this is a new request */
ino = autofs4_dentry_ino(dentry);
if (!ino)
return 1;
/*
* If we've been asked to wait on an existing expire (NFY_NONE)
* but there is no wait in the queue ...
*/
if (notify == NFY_NONE) {
/*
* Either we've betean the pending expire to post it's
* wait or it finished while we waited on the mutex.
* So we need to wait till either, the wait appears
* or the expire finishes.
*/
while (ino->flags & AUTOFS_INF_EXPIRING) {
mutex_unlock(&sbi->wq_mutex);
schedule_timeout_interruptible(HZ/10);
if (mutex_lock_interruptible(&sbi->wq_mutex))
return -EINTR;
wq = autofs4_find_wait(sbi, qstr);
if (wq) {
*wait = wq;
return 1;
}
}
/*
* Not ideal but the status has already gone. Of the two
* cases where we wait on NFY_NONE neither depend on the
* return status of the wait.
*/
return 0;
}
/*
* If we've been asked to trigger a mount and the request
* completed while we waited on the mutex ...
*/
if (notify == NFY_MOUNT) {
/*
* If the dentry was successfully mounted while we slept
* on the wait queue mutex we can return success. If it
* isn't mounted (doesn't have submounts for the case of
* a multi-mount with no mount at it's base) we can
* continue on and create a new request.
*/
if (have_submounts(dentry))
return 0;
}
return 1;
}
static int test_by_type(struct path *path, void *p)
{
struct autofs_info *ino = autofs4_dentry_ino(path->dentry);
return ino && ino->sbi->type & *(unsigned *)p;
}
/*
* Check if the given path is a mountpoint.
*
* If we are supplied with the file descriptor of an autofs
* mount we're looking for a specific mount. In this case
* the path is considered a mountpoint if it is itself a
* mountpoint or contains a mount, such as a multi-mount
* without a root mount. In this case we return 1 if the
* path is a mount point and the super magic of the covering
* mount if there is one or 0 if it isn't a mountpoint.
*
* If we aren't supplied with a file descriptor then we
* lookup the nameidata of the path and check if it is the
* root of a mount. If a type is given we are looking for
* a particular autofs mount and if we don't find a match
* we return fail. If the located nameidata path is the
* root of a mount we return 1 along with the super magic
* of the mount or 0 otherwise.
*
* In both cases the the device number (as returned by
* new_encode_dev()) is also returned.
*/
static int autofs_dev_ioctl_ismountpoint(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct nameidata nd;
const char *path;
unsigned int type;
int err = -ENOENT;
if (param->size <= sizeof(*param)) {
err = -EINVAL;
goto out;
}
path = param->path;
type = param->arg1;
param->arg1 = 0;
param->arg2 = 0;
if (!fp || param->ioctlfd == -1) {
if (type == AUTOFS_TYPE_ANY) {
struct super_block *sb;
err = path_lookup(path, LOOKUP_FOLLOW, &nd);
if (err)
goto out;
sb = nd.path.dentry->d_sb;
param->arg1 = new_encode_dev(sb->s_dev);
} else {
struct autofs_info *ino;
err = path_lookup(path, LOOKUP_PARENT, &nd);
if (err)
goto out;
err = autofs_dev_ioctl_find_sbi_type(&nd, type);
if (err)
goto out_release;
ino = autofs4_dentry_ino(nd.path.dentry);
param->arg1 = autofs4_get_dev(ino->sbi);
}
err = 0;
if (nd.path.dentry->d_inode &&
nd.path.mnt->mnt_root == nd.path.dentry) {
err = 1;
param->arg2 = nd.path.dentry->d_inode->i_sb->s_magic;
}
} else {
dev_t devid = new_encode_dev(sbi->sb->s_dev);
err = path_lookup(path, LOOKUP_PARENT, &nd);
if (err)
goto out;
err = autofs_dev_ioctl_find_super(&nd, devid);
if (err)
goto out_release;
param->arg1 = autofs4_get_dev(sbi);
err = have_submounts(nd.path.dentry);
if (nd.path.mnt->mnt_mountpoint != nd.path.mnt->mnt_root) {
if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
struct inode *inode = nd.path.dentry->d_inode;
param->arg2 = inode->i_sb->s_magic;
}
}
}
out_release:
path_put(&nd.path);
out:
return err;
}
static int try_to_fill_dentry(struct dentry *dentry,
struct super_block *sb,
struct autofs_sb_info *sbi)
{
struct autofs_info *de_info = autofs4_dentry_ino(dentry);
int status = 0;
/* Block on any pending expiry here; invalidate the dentry
when expiration is done to trigger mount request with a new
dentry */
if (de_info && (de_info->flags & AUTOFS_INF_EXPIRING)) {
DPRINTK(("try_to_fill_entry: waiting for expire %p name=%.*s, flags&PENDING=%s de_info=%p de_info->flags=%x\n",
dentry, dentry->d_name.len, dentry->d_name.name,
dentry->d_flags & DCACHE_AUTOFS_PENDING?"t":"f",
de_info, de_info?de_info->flags:0));
status = autofs4_wait(sbi, &dentry->d_name, NFY_NONE);
DPRINTK(("try_to_fill_entry: expire done status=%d\n", status));
return 0;
}
DPRINTK(("try_to_fill_entry: dentry=%p %.*s ino=%p\n",
dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode));
/* Wait for a pending mount, triggering one if there isn't one already */
while(dentry->d_inode == NULL) {
DPRINTK(("try_to_fill_entry: waiting for mount name=%.*s, de_info=%p de_info->flags=%x\n",
dentry->d_name.len, dentry->d_name.name,
de_info, de_info?de_info->flags:0));
status = autofs4_wait(sbi, &dentry->d_name, NFY_MOUNT);
DPRINTK(("try_to_fill_entry: mount done status=%d\n", status));
if (status && dentry->d_inode)
return 0; /* Try to get the kernel to invalidate this dentry */
/* Turn this into a real negative dentry? */
if (status == -ENOENT) {
dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT;
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
return 1;
} else if (status) {
/* Return a negative dentry, but leave it "pending" */
return 1;
}
}
/* If this is an unused directory that isn't a mount point,
bitch at the daemon and fix it in user space */
spin_lock(&dcache_lock);
if (S_ISDIR(dentry->d_inode->i_mode) &&
!d_mountpoint(dentry) &&
list_empty(&dentry->d_subdirs)) {
DPRINTK(("try_to_fill_entry: mounting existing dir\n"));
spin_unlock(&dcache_lock);
return autofs4_wait(sbi, &dentry->d_name, NFY_MOUNT) == 0;
}
spin_unlock(&dcache_lock);
/* We don't update the usages for the autofs daemon itself, this
is necessary for recursive autofs mounts */
if (!autofs4_oz_mode(sbi))
autofs4_update_usage(dentry);
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
return 1;
}
int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
enum autofs_notify notify)
{
struct autofs_info *ino;
struct autofs_wait_queue *wq;
char *name;
unsigned int len = 0;
unsigned int hash = 0;
int status, type;
/* In catatonic mode, we don't wait for nobody */
if (sbi->catatonic)
return -ENOENT;
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
/* If this is a direct mount request create a dummy name */
if (IS_ROOT(tx_cache_get_dentry(dentry)) && (sbi->type & AUTOFS_TYPE_DIRECT))
len = sprintf(name, "%p", dentry);
else {
len = autofs4_getpath(sbi, dentry, &name);
if (!len) {
kfree(name);
return -ENOENT;
}
}
hash = full_name_hash(name, len);
if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(name);
return -EINTR;
}
wq = autofs4_find_wait(sbi, name, hash, len);
ino = autofs4_dentry_ino(dentry);
if (!wq && ino && notify == NFY_NONE) {
/*
* Either we've betean the pending expire to post it's
* wait or it finished while we waited on the mutex.
* So we need to wait till either, the wait appears
* or the expire finishes.
*/
while (ino->flags & AUTOFS_INF_EXPIRING) {
mutex_unlock(&sbi->wq_mutex);
schedule_timeout_interruptible(HZ/10);
if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(name);
return -EINTR;
}
wq = autofs4_find_wait(sbi, name, hash, len);
if (wq)
break;
}
/*
* Not ideal but the status has already gone. Of the two
* cases where we wait on NFY_NONE neither depend on the
* return status of the wait.
*/
if (!wq) {
kfree(name);
mutex_unlock(&sbi->wq_mutex);
return 0;
}
}
if (!wq) {
/* Create a new wait queue */
wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
if (!wq) {
kfree(name);
mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->wait_queue_token = autofs4_next_wait_queue;
if (++autofs4_next_wait_queue == 0)
autofs4_next_wait_queue = 1;
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
wq->hash = hash;
wq->name = name;
wq->len = len;
wq->dev = autofs4_get_dev(sbi);
wq->ino = autofs4_get_ino(sbi);
wq->uid = current->uid;
wq->gid = current->gid;
wq->pid = current->pid;
wq->tgid = current->tgid;
wq->status = -EINTR; /* Status return if interrupted */
atomic_set(&wq->wait_ctr, 2);
mutex_unlock(&sbi->wq_mutex);
if (sbi->version < 5) {
if (notify == NFY_MOUNT)
type = autofs_ptype_missing;
else
type = autofs_ptype_expire_multi;
} else {
if (notify == NFY_MOUNT)
type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
autofs_ptype_missing_direct :
autofs_ptype_missing_indirect;
else
type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
autofs_ptype_expire_direct :
autofs_ptype_expire_indirect;
}
DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
/* autofs4_notify_daemon() may block */
autofs4_notify_daemon(sbi, wq, type);
} else {
atomic_inc(&wq->wait_ctr);
mutex_unlock(&sbi->wq_mutex);
kfree(name);
DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
}
/* wq->name is NULL if and only if the lock is already released */
if (sbi->catatonic) {
/* We might have slept, so check again for catatonic mode */
wq->status = -ENOENT;
kfree(wq->name);
wq->name = NULL;
}
if (wq->name) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
oldset = current->blocked;
siginitsetinv(¤t->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
wait_event_interruptible(wq->queue, wq->name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
} else {
DPRINTK("skipped sleeping");
}
status = wq->status;
/* Are we the last process to need status? */
if (atomic_dec_and_test(&wq->wait_ctr))
kfree(wq);
return status;
}
