#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/stat.h>
+#include <linux/slab.h>
#include <linux/param.h>
#include <linux/time.h>
-#include <linux/smp_lock.h>
+#include <linux/compat.h>
+#include <linux/mutex.h>
+
#include "autofs_i.h"
static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);
static int autofs4_dir_unlink(struct inode *,struct dentry *);
static int autofs4_dir_rmdir(struct inode *,struct dentry *);
static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
-static int autofs4_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long);
+static long autofs4_root_ioctl(struct file *,unsigned int,unsigned long);
+#ifdef CONFIG_COMPAT
+static long autofs4_root_compat_ioctl(struct file *,unsigned int,unsigned long);
+#endif
static int autofs4_dir_open(struct inode *inode, struct file *file);
-static int autofs4_dir_close(struct inode *inode, struct file *file);
-static int autofs4_dir_readdir(struct file * filp, void * dirent, filldir_t filldir);
-static int autofs4_root_readdir(struct file * filp, void * dirent, filldir_t filldir);
static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *);
-static void *autofs4_follow_link(struct dentry *, struct nameidata *);
+static struct vfsmount *autofs4_d_automount(struct path *);
+static int autofs4_d_manage(struct dentry *, bool);
+static void autofs4_dentry_release(struct dentry *);
const struct file_operations autofs4_root_operations = {
.open = dcache_dir_open,
.release = dcache_dir_close,
.read = generic_read_dir,
- .readdir = autofs4_root_readdir,
- .ioctl = autofs4_root_ioctl,
+ .readdir = dcache_readdir,
+ .llseek = dcache_dir_lseek,
+ .unlocked_ioctl = autofs4_root_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = autofs4_root_compat_ioctl,
+#endif
};
const struct file_operations autofs4_dir_operations = {
.open = autofs4_dir_open,
- .release = autofs4_dir_close,
+ .release = dcache_dir_close,
.read = generic_read_dir,
- .readdir = autofs4_dir_readdir,
+ .readdir = dcache_readdir,
+ .llseek = dcache_dir_lseek,
};
-struct inode_operations autofs4_indirect_root_inode_operations = {
+const struct inode_operations autofs4_dir_inode_operations = {
.lookup = autofs4_lookup,
.unlink = autofs4_dir_unlink,
.symlink = autofs4_dir_symlink,
.rmdir = autofs4_dir_rmdir,
};
-struct inode_operations autofs4_direct_root_inode_operations = {
- .lookup = autofs4_lookup,
- .unlink = autofs4_dir_unlink,
- .mkdir = autofs4_dir_mkdir,
- .rmdir = autofs4_dir_rmdir,
- .follow_link = autofs4_follow_link,
-};
-
-struct inode_operations autofs4_dir_inode_operations = {
- .lookup = autofs4_lookup,
- .unlink = autofs4_dir_unlink,
- .symlink = autofs4_dir_symlink,
- .mkdir = autofs4_dir_mkdir,
- .rmdir = autofs4_dir_rmdir,
+const struct dentry_operations autofs4_dentry_operations = {
+ .d_automount = autofs4_d_automount,
+ .d_manage = autofs4_d_manage,
+ .d_release = autofs4_dentry_release,
};
-static int autofs4_root_readdir(struct file *file, void *dirent,
- filldir_t filldir)
+static void autofs4_add_active(struct dentry *dentry)
{
- struct autofs_sb_info *sbi = autofs4_sbi(file->f_dentry->d_sb);
- int oz_mode = autofs4_oz_mode(sbi);
-
- DPRINTK("called, filp->f_pos = %lld", file->f_pos);
-
- /*
- * Don't set reghost flag if:
- * 1) f_pos is larger than zero -- we've already been here.
- * 2) we haven't even enabled reghosting in the 1st place.
- * 3) this is the daemon doing a readdir
- */
- if (oz_mode && file->f_pos == 0 && sbi->reghost_enabled)
- sbi->needs_reghost = 1;
-
- DPRINTK("needs_reghost = %d", sbi->needs_reghost);
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ if (ino) {
+ spin_lock(&sbi->lookup_lock);
+ if (!ino->active_count) {
+ if (list_empty(&ino->active))
+ list_add(&ino->active, &sbi->active_list);
+ }
+ ino->active_count++;
+ spin_unlock(&sbi->lookup_lock);
+ }
+ return;
+}
- return dcache_readdir(file, dirent, filldir);
+static void autofs4_del_active(struct dentry *dentry)
+{
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+ if (ino) {
+ spin_lock(&sbi->lookup_lock);
+ ino->active_count--;
+ if (!ino->active_count) {
+ if (!list_empty(&ino->active))
+ list_del_init(&ino->active);
+ }
+ spin_unlock(&sbi->lookup_lock);
+ }
+ return;
}
static int autofs4_dir_open(struct inode *inode, struct file *file)
{
- struct dentry *dentry = file->f_dentry;
- struct vfsmount *mnt = file->f_vfsmnt;
+ struct dentry *dentry = file->f_path.dentry;
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
- struct dentry *cursor;
- int status;
-
- status = dcache_dir_open(inode, file);
- if (status)
- goto out;
-
- cursor = file->private_data;
- cursor->d_fsdata = NULL;
DPRINTK("file=%p dentry=%p %.*s",
file, dentry, dentry->d_name.len, dentry->d_name.name);
if (autofs4_oz_mode(sbi))
goto out;
- if (autofs4_ispending(dentry)) {
- DPRINTK("dentry busy");
- dcache_dir_close(inode, file);
- status = -EBUSY;
- goto out;
+ /*
+ * An empty directory in an autofs file system is always a
+ * mount point. The daemon must have failed to mount this
+ * during lookup so it doesn't exist. This can happen, for
+ * example, if user space returns an incorrect status for a
+ * mount request. Otherwise we're doing a readdir on the
+ * autofs file system so just let the libfs routines handle
+ * it.
+ */
+ spin_lock(&sbi->lookup_lock);
+ spin_lock(&dentry->d_lock);
+ if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&sbi->lookup_lock);
+ return -ENOENT;
}
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&sbi->lookup_lock);
- status = -ENOENT;
- if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) {
- struct nameidata nd;
- int empty, ret;
+out:
+ return dcache_dir_open(inode, file);
+}
- /* In case there are stale directory dentrys from a failed mount */
- spin_lock(&dcache_lock);
- empty = list_empty(&dentry->d_subdirs);
- spin_unlock(&dcache_lock);
+static void autofs4_dentry_release(struct dentry *de)
+{
+ struct autofs_info *ino = autofs4_dentry_ino(de);
+ struct autofs_sb_info *sbi = autofs4_sbi(de->d_sb);
- if (!empty)
- d_invalidate(dentry);
+ DPRINTK("releasing %p", de);
- nd.flags = LOOKUP_DIRECTORY;
- ret = (dentry->d_op->d_revalidate)(dentry, &nd);
+ if (!ino)
+ return;
- if (ret <= 0) {
- if (ret < 0)
- status = ret;
- dcache_dir_close(inode, file);
- goto out;
- }
+ if (sbi) {
+ spin_lock(&sbi->lookup_lock);
+ if (!list_empty(&ino->active))
+ list_del(&ino->active);
+ if (!list_empty(&ino->expiring))
+ list_del(&ino->expiring);
+ spin_unlock(&sbi->lookup_lock);
}
- if (d_mountpoint(dentry)) {
- struct file *fp = NULL;
- struct vfsmount *fp_mnt = mntget(mnt);
- struct dentry *fp_dentry = dget(dentry);
-
- if (!autofs4_follow_mount(&fp_mnt, &fp_dentry)) {
- dput(fp_dentry);
- mntput(fp_mnt);
- dcache_dir_close(inode, file);
- goto out;
- }
-
- fp = dentry_open(fp_dentry, fp_mnt, file->f_flags);
- status = PTR_ERR(fp);
- if (IS_ERR(fp)) {
- dcache_dir_close(inode, file);
- goto out;
- }
- cursor->d_fsdata = fp;
- }
- return 0;
-out:
- return status;
+ autofs4_free_ino(ino);
}
-static int autofs4_dir_close(struct inode *inode, struct file *file)
+static struct dentry *autofs4_lookup_active(struct dentry *dentry)
{
- struct dentry *dentry = file->f_dentry;
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
- struct dentry *cursor = file->private_data;
- int status = 0;
-
- DPRINTK("file=%p dentry=%p %.*s",
- file, dentry, dentry->d_name.len, dentry->d_name.name);
-
- if (autofs4_oz_mode(sbi))
- goto out;
-
- if (autofs4_ispending(dentry)) {
- DPRINTK("dentry busy");
- status = -EBUSY;
- goto out;
- }
-
- if (d_mountpoint(dentry)) {
- struct file *fp = cursor->d_fsdata;
- if (!fp) {
- status = -ENOENT;
- goto out;
+ struct dentry *parent = dentry->d_parent;
+ struct qstr *name = &dentry->d_name;
+ unsigned int len = name->len;
+ unsigned int hash = name->hash;
+ const unsigned char *str = name->name;
+ struct list_head *p, *head;
+
+ spin_lock(&sbi->lookup_lock);
+ head = &sbi->active_list;
+ list_for_each(p, head) {
+ struct autofs_info *ino;
+ struct dentry *active;
+ struct qstr *qstr;
+
+ ino = list_entry(p, struct autofs_info, active);
+ active = ino->dentry;
+
+ spin_lock(&active->d_lock);
+
+ /* Already gone? */
+ if (active->d_count == 0)
+ goto next;
+
+ qstr = &active->d_name;
+
+ if (active->d_name.hash != hash)
+ goto next;
+ if (active->d_parent != parent)
+ goto next;
+
+ if (qstr->len != len)
+ goto next;
+ if (memcmp(qstr->name, str, len))
+ goto next;
+
+ if (d_unhashed(active)) {
+ dget_dlock(active);
+ spin_unlock(&active->d_lock);
+ spin_unlock(&sbi->lookup_lock);
+ return active;
}
- filp_close(fp, current->files);
+next:
+ spin_unlock(&active->d_lock);
}
-out:
- dcache_dir_close(inode, file);
- return status;
+ spin_unlock(&sbi->lookup_lock);
+
+ return NULL;
}
-static int autofs4_dir_readdir(struct file *file, void *dirent, filldir_t filldir)
+static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
{
- struct dentry *dentry = file->f_dentry;
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
- struct dentry *cursor = file->private_data;
- int status;
-
- DPRINTK("file=%p dentry=%p %.*s",
- file, dentry, dentry->d_name.len, dentry->d_name.name);
-
- if (autofs4_oz_mode(sbi))
- goto out;
-
- if (autofs4_ispending(dentry)) {
- DPRINTK("dentry busy");
- return -EBUSY;
+ struct dentry *parent = dentry->d_parent;
+ struct qstr *name = &dentry->d_name;
+ unsigned int len = name->len;
+ unsigned int hash = name->hash;
+ const unsigned char *str = name->name;
+ struct list_head *p, *head;
+
+ spin_lock(&sbi->lookup_lock);
+ head = &sbi->expiring_list;
+ list_for_each(p, head) {
+ struct autofs_info *ino;
+ struct dentry *expiring;
+ struct qstr *qstr;
+
+ ino = list_entry(p, struct autofs_info, expiring);
+ expiring = ino->dentry;
+
+ spin_lock(&expiring->d_lock);
+
+ /* Bad luck, we've already been dentry_iput */
+ if (!expiring->d_inode)
+ goto next;
+
+ qstr = &expiring->d_name;
+
+ if (expiring->d_name.hash != hash)
+ goto next;
+ if (expiring->d_parent != parent)
+ goto next;
+
+ if (qstr->len != len)
+ goto next;
+ if (memcmp(qstr->name, str, len))
+ goto next;
+
+ if (d_unhashed(expiring)) {
+ dget_dlock(expiring);
+ spin_unlock(&expiring->d_lock);
+ spin_unlock(&sbi->lookup_lock);
+ return expiring;
+ }
+next:
+ spin_unlock(&expiring->d_lock);
}
+ spin_unlock(&sbi->lookup_lock);
- if (d_mountpoint(dentry)) {
- struct file *fp = cursor->d_fsdata;
-
- if (!fp)
- return -ENOENT;
-
- if (!fp->f_op || !fp->f_op->readdir)
- goto out;
-
- status = vfs_readdir(fp, filldir, dirent);
- file->f_pos = fp->f_pos;
- if (status)
- autofs4_copy_atime(file, fp);
- return status;
- }
-out:
- return dcache_readdir(file, dirent, filldir);
+ return NULL;
}
-static int try_to_fill_dentry(struct dentry *dentry, int flags)
+static int autofs4_mount_wait(struct dentry *dentry)
{
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
struct autofs_info *ino = 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 (ino && (ino->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);
+ if (ino->flags & AUTOFS_INF_PENDING) {
+ DPRINTK("waiting for mount name=%.*s",
+ dentry->d_name.len, dentry->d_name.name);
+ status = autofs4_wait(sbi, dentry, NFY_MOUNT);
+ DPRINTK("mount wait done status=%d", status);
+ }
+ ino->last_used = jiffies;
+ return status;
+}
- DPRINTK("expire done status=%d", status);
+static int do_expire_wait(struct dentry *dentry)
+{
+ struct dentry *expiring;
+ expiring = autofs4_lookup_expiring(dentry);
+ if (!expiring)
+ return autofs4_expire_wait(dentry);
+ else {
/*
- * If the directory still exists the mount request must
- * continue otherwise it can't be followed at the right
- * time during the walk.
+ * If we are racing with expire the request might not
+ * be quite complete, but the directory has been removed
+ * so it must have been successful, just wait for it.
*/
- status = d_invalidate(dentry);
- if (status != -EBUSY)
- return -ENOENT;
+ autofs4_expire_wait(expiring);
+ autofs4_del_expiring(expiring);
+ dput(expiring);
}
+ return 0;
+}
- DPRINTK("dentry=%p %.*s ino=%p",
- dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
+static struct dentry *autofs4_mountpoint_changed(struct path *path)
+{
+ struct dentry *dentry = path->dentry;
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
/*
- * Wait for a pending mount, triggering one if there
- * isn't one already
+ * If this is an indirect mount the dentry could have gone away
+ * as a result of an expire and a new one created.
*/
- 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);
-
- /* Turn this into a real negative dentry? */
- if (status == -ENOENT) {
- spin_lock(&dentry->d_lock);
- dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
- spin_unlock(&dentry->d_lock);
- return status;
- } else if (status) {
- /* Return a negative dentry, but leave it "pending" */
- return status;
- }
- /* 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 status;
- }
- }
-
- /* Initialize expiry counter after successful mount */
- if (ino)
+ if (autofs_type_indirect(sbi->type) && d_unhashed(dentry)) {
+ struct dentry *parent = dentry->d_parent;
+ struct autofs_info *ino;
+ struct dentry *new = d_lookup(parent, &dentry->d_name);
+ if (!new)
+ return NULL;
+ ino = autofs4_dentry_ino(new);
ino->last_used = jiffies;
-
- spin_lock(&dentry->d_lock);
- dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
- spin_unlock(&dentry->d_lock);
- return status;
+ dput(path->dentry);
+ path->dentry = new;
+ }
+ return path->dentry;
}
-/* For autofs direct mounts the follow link triggers the mount */
-static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
+static struct vfsmount *autofs4_d_automount(struct path *path)
{
+ struct dentry *dentry = path->dentry;
struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
- int oz_mode = autofs4_oz_mode(sbi);
- unsigned int lookup_type;
int status;
- DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d",
- dentry, dentry->d_name.len, dentry->d_name.name, oz_mode,
- nd->flags);
-
- /* If it's our master or we shouldn't trigger a mount we're done */
- lookup_type = nd->flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY);
- if (oz_mode || !lookup_type)
- goto done;
-
- /* If an expire request is pending wait for it. */
- if (ino && (ino->flags & AUTOFS_INF_EXPIRING)) {
- DPRINTK("waiting for active request %p name=%.*s",
- dentry, dentry->d_name.len, dentry->d_name.name);
-
- status = autofs4_wait(sbi, dentry, NFY_NONE);
+ DPRINTK("dentry=%p %.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
- DPRINTK("request done status=%d", status);
- }
+ /* The daemon never triggers a mount. */
+ if (autofs4_oz_mode(sbi))
+ return NULL;
/*
- * If the dentry contains directories then it is an
- * autofs multi-mount with no root mount offset. So
- * don't try to mount it again.
+ * If an expire request is pending everyone must wait.
+ * If the expire fails we're still mounted so continue
+ * the follow and return. A return of -EAGAIN (which only
+ * happens with indirect mounts) means the expire completed
+ * and the directory was removed, so just go ahead and try
+ * the mount.
*/
- spin_lock(&dcache_lock);
- if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
- spin_unlock(&dcache_lock);
-
- status = try_to_fill_dentry(dentry, 0);
+ status = do_expire_wait(dentry);
+ if (status && status != -EAGAIN)
+ return NULL;
+
+ /* Callback to the daemon to perform the mount or wait */
+ spin_lock(&sbi->fs_lock);
+ if (ino->flags & AUTOFS_INF_PENDING) {
+ spin_unlock(&sbi->fs_lock);
+ status = autofs4_mount_wait(dentry);
if (status)
- goto out_error;
+ return ERR_PTR(status);
+ spin_lock(&sbi->fs_lock);
+ goto done;
+ }
+ /*
+ * If the dentry is a symlink it's equivalent to a directory
+ * having d_mountpoint() true, so there's no need to call back
+ * to the daemon.
+ */
+ if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode))
+ goto done;
+ if (!d_mountpoint(dentry)) {
/*
- * The mount succeeded but if there is no root mount
- * it must be an autofs multi-mount with no root offset
- * so we don't need to follow the mount.
+ * It's possible that user space hasn't removed directories
+ * after umounting a rootless multi-mount, although it
+ * should. For v5 have_submounts() is sufficient to handle
+ * this because the leaves of the directory tree under the
+ * mount never trigger mounts themselves (they have an autofs
+ * trigger mount mounted on them). But v4 pseudo direct mounts
+ * do need the leaves to to trigger mounts. In this case we
+ * have no choice but to use the list_empty() check and
+ * require user space behave.
*/
- if (d_mountpoint(dentry)) {
- if (!autofs4_follow_mount(&nd->mnt, &nd->dentry)) {
- status = -ENOENT;
- goto out_error;
+ if (sbi->version > 4) {
+ if (have_submounts(dentry))
+ goto done;
+ } else {
+ spin_lock(&dentry->d_lock);
+ if (!list_empty(&dentry->d_subdirs)) {
+ spin_unlock(&dentry->d_lock);
+ goto done;
}
+ spin_unlock(&dentry->d_lock);
}
-
- goto done;
+ ino->flags |= AUTOFS_INF_PENDING;
+ spin_unlock(&sbi->fs_lock);
+ status = autofs4_mount_wait(dentry);
+ if (status)
+ return ERR_PTR(status);
+ spin_lock(&sbi->fs_lock);
+ ino->flags &= ~AUTOFS_INF_PENDING;
}
- spin_unlock(&dcache_lock);
-
done:
- return NULL;
-
-out_error:
- path_release(nd);
- return ERR_PTR(status);
-}
-
-/*
- * Revalidate is called on every cache lookup. Some of those
- * cache lookups may actually happen while the dentry is not
- * yet completely filled in, and revalidate has to delay such
- * lookups..
- */
-static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
-{
- struct inode *dir = dentry->d_parent->d_inode;
- struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
- int oz_mode = autofs4_oz_mode(sbi);
- int flags = nd ? nd->flags : 0;
- int status = 1;
-
- /* Pending dentry */
- if (autofs4_ispending(dentry)) {
- /* The daemon never causes a mount to trigger */
- if (oz_mode)
- return 1;
-
+ if (!(ino->flags & AUTOFS_INF_EXPIRING)) {
/*
- * A zero status is success otherwise we have a
- * negative error code.
+ * Any needed mounting has been completed and the path
+ * updated so clear DCACHE_NEED_AUTOMOUNT so we don't
+ * call ->d_automount() on rootless multi-mounts since
+ * it can lead to an incorrect ELOOP error return.
+ *
+ * Only clear DMANAGED_AUTOMOUNT for rootless multi-mounts and
+ * symlinks as in all other cases the dentry will be covered by
+ * an actual mount so ->d_automount() won't be called during
+ * the follow.
*/
- status = try_to_fill_dentry(dentry, flags);
- if (status == 0)
- return 1;
-
- return status;
+ spin_lock(&dentry->d_lock);
+ if ((!d_mountpoint(dentry) &&
+ !list_empty(&dentry->d_subdirs)) ||
+ (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)))
+ __managed_dentry_clear_automount(dentry);
+ spin_unlock(&dentry->d_lock);
}
+ spin_unlock(&sbi->fs_lock);
- /* Negative dentry.. invalidate if "old" */
- if (dentry->d_inode == NULL)
- return 0;
-
- /* Check for a non-mountpoint directory with no contents */
- spin_lock(&dcache_lock);
- if (S_ISDIR(dentry->d_inode->i_mode) &&
- !d_mountpoint(dentry) &&
- __simple_empty(dentry)) {
- DPRINTK("dentry=%p %.*s, emptydir",
- dentry, dentry->d_name.len, dentry->d_name.name);
- spin_unlock(&dcache_lock);
- /* The daemon never causes a mount to trigger */
- if (oz_mode)
- return 1;
-
- /*
- * A zero status is success otherwise we have a
- * negative error code.
- */
- status = try_to_fill_dentry(dentry, flags);
- if (status == 0)
- return 1;
-
- return status;
- }
- spin_unlock(&dcache_lock);
+ /* Mount succeeded, check if we ended up with a new dentry */
+ dentry = autofs4_mountpoint_changed(path);
+ if (!dentry)
+ return ERR_PTR(-ENOENT);
- return 1;
+ return NULL;
}
-void autofs4_dentry_release(struct dentry *de)
+int autofs4_d_manage(struct dentry *dentry, bool rcu_walk)
{
- struct autofs_info *inf;
-
- DPRINTK("releasing %p", de);
-
- inf = autofs4_dentry_ino(de);
- de->d_fsdata = NULL;
+ struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
- if (inf) {
- inf->dentry = NULL;
- inf->inode = NULL;
+ DPRINTK("dentry=%p %.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
- autofs4_free_ino(inf);
+ /* The daemon never waits. */
+ if (autofs4_oz_mode(sbi)) {
+ if (rcu_walk)
+ return 0;
+ if (!d_mountpoint(dentry))
+ return -EISDIR;
+ return 0;
}
-}
-/* For dentries of directories in the root dir */
-static struct dentry_operations autofs4_root_dentry_operations = {
- .d_revalidate = autofs4_revalidate,
- .d_release = autofs4_dentry_release,
-};
+ /* We need to sleep, so we need pathwalk to be in ref-mode */
+ if (rcu_walk)
+ return -ECHILD;
-/* For other dentries */
-static struct dentry_operations autofs4_dentry_operations = {
- .d_revalidate = autofs4_revalidate,
- .d_release = autofs4_dentry_release,
-};
+ /* Wait for pending expires */
+ do_expire_wait(dentry);
+
+ /*
+ * This dentry may be under construction so wait on mount
+ * completion.
+ */
+ return autofs4_mount_wait(dentry);
+}
/* Lookups in the root directory */
static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
struct autofs_sb_info *sbi;
- int oz_mode;
+ struct autofs_info *ino;
+ struct dentry *active;
- DPRINTK("name = %.*s",
- dentry->d_name.len, dentry->d_name.name);
+ DPRINTK("name = %.*s", dentry->d_name.len, dentry->d_name.name);
/* File name too long to exist */
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
sbi = autofs4_sbi(dir->i_sb);
- oz_mode = autofs4_oz_mode(sbi);
DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
- current->pid, process_group(current), sbi->catatonic, oz_mode);
+ current->pid, task_pgrp_nr(current), sbi->catatonic,
+ autofs4_oz_mode(sbi));
- /*
- * Mark the dentry incomplete, but add it. This is needed so
- * that the VFS layer knows about the dentry, and we can count
- * on catching any lookups through the revalidate.
- *
- * Let all the hard work be done by the revalidate function that
- * needs to be able to do this anyway..
- *
- * We need to do this before we release the directory semaphore.
- */
- dentry->d_op = &autofs4_root_dentry_operations;
+ active = autofs4_lookup_active(dentry);
+ if (active) {
+ return active;
+ } else {
+ /*
+ * A dentry that is not within the root can never trigger a
+ * mount operation, unless the directory already exists, so we
+ * can return fail immediately. The daemon however does need
+ * to create directories within the file system.
+ */
+ if (!autofs4_oz_mode(sbi) && !IS_ROOT(dentry->d_parent))
+ return ERR_PTR(-ENOENT);
- if (!oz_mode) {
- spin_lock(&dentry->d_lock);
- dentry->d_flags |= DCACHE_AUTOFS_PENDING;
- spin_unlock(&dentry->d_lock);
- }
- dentry->d_fsdata = NULL;
- d_add(dentry, NULL);
+ /* Mark entries in the root as mount triggers */
+ if (autofs_type_indirect(sbi->type) && IS_ROOT(dentry->d_parent))
+ __managed_dentry_set_managed(dentry);
- if (dentry->d_op && dentry->d_op->d_revalidate) {
- mutex_unlock(&dir->i_mutex);
- (dentry->d_op->d_revalidate)(dentry, nd);
- mutex_lock(&dir->i_mutex);
- }
+ ino = autofs4_new_ino(sbi);
+ if (!ino)
+ return ERR_PTR(-ENOMEM);
- /*
- * If we are still pending, check if we had to handle
- * a signal. If so we can force a restart..
- */
- if (dentry->d_flags & DCACHE_AUTOFS_PENDING) {
- /* See if we were interrupted */
- if (signal_pending(current)) {
- sigset_t *sigset = ¤t->pending.signal;
- if (sigismember (sigset, SIGKILL) ||
- sigismember (sigset, SIGQUIT) ||
- sigismember (sigset, SIGINT)) {
- return ERR_PTR(-ERESTARTNOINTR);
- }
- }
- spin_lock(&dentry->d_lock);
- dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
- spin_unlock(&dentry->d_lock);
- }
+ dentry->d_fsdata = ino;
+ ino->dentry = dentry;
- /*
- * If this dentry is unhashed, then we shouldn't honour this
- * lookup even if the dentry is positive. Returning ENOENT here
- * doesn't do the right thing for all system calls, but it should
- * be OK for the operations we permit from an autofs.
- */
- if (dentry->d_inode && d_unhashed(dentry))
- return ERR_PTR(-ENOENT);
+ autofs4_add_active(dentry);
+ d_instantiate(dentry, NULL);
+ }
return NULL;
}
struct autofs_info *ino = autofs4_dentry_ino(dentry);
struct autofs_info *p_ino;
struct inode *inode;
+ size_t size = strlen(symname);
char *cp;
DPRINTK("%s <- %.*s", symname,
if (!autofs4_oz_mode(sbi))
return -EACCES;
- ino = autofs4_init_ino(ino, sbi, S_IFLNK | 0555);
- if (ino == NULL)
- return -ENOSPC;
+ BUG_ON(!ino);
- ino->size = strlen(symname);
- ino->u.symlink = cp = kmalloc(ino->size + 1, GFP_KERNEL);
+ autofs4_clean_ino(ino);
- if (cp == NULL) {
- kfree(ino);
- return -ENOSPC;
- }
+ autofs4_del_active(dentry);
- strcpy(cp, symname);
+ cp = kmalloc(size + 1, GFP_KERNEL);
+ if (!cp)
+ return -ENOMEM;
- inode = autofs4_get_inode(dir->i_sb, ino);
- d_instantiate(dentry, inode);
+ strcpy(cp, symname);
- if (dir == dir->i_sb->s_root->d_inode)
- dentry->d_op = &autofs4_root_dentry_operations;
- else
- dentry->d_op = &autofs4_dentry_operations;
+ inode = autofs4_get_inode(dir->i_sb, S_IFLNK | 0555);
+ if (!inode) {
+ kfree(cp);
+ if (!dentry->d_fsdata)
+ kfree(ino);
+ return -ENOMEM;
+ }
+ inode->i_private = cp;
+ inode->i_size = size;
+ d_add(dentry, inode);
- dentry->d_fsdata = ino;
- ino->dentry = dget(dentry);
+ dget(dentry);
atomic_inc(&ino->count);
p_ino = autofs4_dentry_ino(dentry->d_parent);
if (p_ino && dentry->d_parent != dentry)
atomic_inc(&p_ino->count);
- ino->inode = inode;
dir->i_mtime = CURRENT_TIME;
* Normal filesystems would do a "d_delete()" to tell the VFS dcache
* that the file no longer exists. However, doing that means that the
* VFS layer can turn the dentry into a negative dentry. We don't want
- * this, because since the unlink is probably the result of an expire.
- * We simply d_drop it, which allows the dentry lookup to remount it
- * if necessary.
+ * this, because the unlink is probably the result of an expire.
+ * We simply d_drop it and add it to a expiring list in the super block,
+ * which allows the dentry lookup to check for an incomplete expire.
*
* If a process is blocked on the dentry waiting for the expire to finish,
* it will invalidate the dentry and try to mount with a new one.
struct autofs_info *p_ino;
/* This allows root to remove symlinks */
- if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
+ if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN))
return -EACCES;
if (atomic_dec_and_test(&ino->count)) {
dir->i_mtime = CURRENT_TIME;
- d_drop(dentry);
+ spin_lock(&sbi->lookup_lock);
+ __autofs4_add_expiring(dentry);
+ spin_lock(&dentry->d_lock);
+ __d_drop(dentry);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&sbi->lookup_lock);
return 0;
}
+/*
+ * Version 4 of autofs provides a pseudo direct mount implementation
+ * that relies on directories at the leaves of a directory tree under
+ * an indirect mount to trigger mounts. To allow for this we need to
+ * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
+ * of the directory tree. There is no need to clear the automount flag
+ * following a mount or restore it after an expire because these mounts
+ * are always covered. However, it is necessary to ensure that these
+ * flags are clear on non-empty directories to avoid unnecessary calls
+ * during path walks.
+ */
+static void autofs_set_leaf_automount_flags(struct dentry *dentry)
+{
+ struct dentry *parent;
+
+ /* root and dentrys in the root are already handled */
+ if (IS_ROOT(dentry->d_parent))
+ return;
+
+ managed_dentry_set_managed(dentry);
+
+ parent = dentry->d_parent;
+ /* only consider parents below dentrys in the root */
+ if (IS_ROOT(parent->d_parent))
+ return;
+ managed_dentry_clear_managed(parent);
+ return;
+}
+
+static void autofs_clear_leaf_automount_flags(struct dentry *dentry)
+{
+ struct list_head *d_child;
+ struct dentry *parent;
+
+ /* flags for dentrys in the root are handled elsewhere */
+ if (IS_ROOT(dentry->d_parent))
+ return;
+
+ managed_dentry_clear_managed(dentry);
+
+ parent = dentry->d_parent;
+ /* only consider parents below dentrys in the root */
+ if (IS_ROOT(parent->d_parent))
+ return;
+ d_child = &dentry->d_u.d_child;
+ /* Set parent managed if it's becoming empty */
+ if (d_child->next == &parent->d_subdirs &&
+ d_child->prev == &parent->d_subdirs)
+ managed_dentry_set_managed(parent);
+ return;
+}
+
static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
{
struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
struct autofs_info *ino = autofs4_dentry_ino(dentry);
struct autofs_info *p_ino;
+ DPRINTK("dentry %p, removing %.*s",
+ dentry, dentry->d_name.len, dentry->d_name.name);
+
if (!autofs4_oz_mode(sbi))
return -EACCES;
- spin_lock(&dcache_lock);
+ spin_lock(&sbi->lookup_lock);
+ spin_lock(&dentry->d_lock);
if (!list_empty(&dentry->d_subdirs)) {
- spin_unlock(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&sbi->lookup_lock);
return -ENOTEMPTY;
}
- spin_lock(&dentry->d_lock);
+ __autofs4_add_expiring(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
+ spin_unlock(&sbi->lookup_lock);
+
+ if (sbi->version < 5)
+ autofs_clear_leaf_automount_flags(dentry);
if (atomic_dec_and_test(&ino->count)) {
p_ino = autofs4_dentry_ino(dentry->d_parent);
struct autofs_info *p_ino;
struct inode *inode;
- if ( !autofs4_oz_mode(sbi) )
+ if (!autofs4_oz_mode(sbi))
return -EACCES;
DPRINTK("dentry %p, creating %.*s",
dentry, dentry->d_name.len, dentry->d_name.name);
- ino = autofs4_init_ino(ino, sbi, S_IFDIR | 0555);
- if (ino == NULL)
- return -ENOSPC;
+ BUG_ON(!ino);
- inode = autofs4_get_inode(dir->i_sb, ino);
- d_instantiate(dentry, inode);
+ autofs4_clean_ino(ino);
- if (dir == dir->i_sb->s_root->d_inode)
- dentry->d_op = &autofs4_root_dentry_operations;
- else
- dentry->d_op = &autofs4_dentry_operations;
+ autofs4_del_active(dentry);
+
+ inode = autofs4_get_inode(dir->i_sb, S_IFDIR | 0555);
+ if (!inode)
+ return -ENOMEM;
+ d_add(dentry, inode);
+
+ if (sbi->version < 5)
+ autofs_set_leaf_automount_flags(dentry);
- dentry->d_fsdata = ino;
- ino->dentry = dget(dentry);
+ dget(dentry);
atomic_inc(&ino->count);
p_ino = autofs4_dentry_ino(dentry->d_parent);
if (p_ino && dentry->d_parent != dentry)
atomic_inc(&p_ino->count);
- ino->inode = inode;
inc_nlink(dir);
dir->i_mtime = CURRENT_TIME;
}
/* Get/set timeout ioctl() operation */
+#ifdef CONFIG_COMPAT
+static inline int autofs4_compat_get_set_timeout(struct autofs_sb_info *sbi,
+ compat_ulong_t __user *p)
+{
+ int rv;
+ unsigned long ntimeout;
+
+ if ((rv = get_user(ntimeout, p)) ||
+ (rv = put_user(sbi->exp_timeout/HZ, p)))
+ return rv;
+
+ if (ntimeout > UINT_MAX/HZ)
+ sbi->exp_timeout = 0;
+ else
+ sbi->exp_timeout = ntimeout * HZ;
+
+ return 0;
+}
+#endif
+
static inline int autofs4_get_set_timeout(struct autofs_sb_info *sbi,
unsigned long __user *p)
{
int rv;
unsigned long ntimeout;
- if ( (rv = get_user(ntimeout, p)) ||
- (rv = put_user(sbi->exp_timeout/HZ, p)) )
+ if ((rv = get_user(ntimeout, p)) ||
+ (rv = put_user(sbi->exp_timeout/HZ, p)))
return rv;
- if ( ntimeout > ULONG_MAX/HZ )
+ if (ntimeout > ULONG_MAX/HZ)
sbi->exp_timeout = 0;
else
sbi->exp_timeout = ntimeout * HZ;
return put_user(sbi->sub_version, p);
}
-/*
- * Tells the daemon whether we need to reghost or not. Also, clears
- * the reghost_needed flag.
- */
-static inline int autofs4_ask_reghost(struct autofs_sb_info *sbi, int __user *p)
-{
- int status;
-
- DPRINTK("returning %d", sbi->needs_reghost);
-
- status = put_user(sbi->needs_reghost, p);
- if ( status )
- return status;
-
- sbi->needs_reghost = 0;
- return 0;
-}
-
-/*
- * Enable / Disable reghosting ioctl() operation
- */
-static inline int autofs4_toggle_reghost(struct autofs_sb_info *sbi, int __user *p)
-{
- int status;
- int val;
-
- status = get_user(val, p);
-
- DPRINTK("reghost = %d", val);
-
- if (status)
- return status;
-
- /* turn on/off reghosting, with the val */
- sbi->reghost_enabled = val;
- return 0;
-}
-
/*
* Tells the daemon whether it can umount the autofs mount.
*/
int is_autofs4_dentry(struct dentry *dentry)
{
return dentry && dentry->d_inode &&
- (dentry->d_op == &autofs4_root_dentry_operations ||
- dentry->d_op == &autofs4_dentry_operations) &&
+ dentry->d_op == &autofs4_dentry_operations &&
dentry->d_fsdata != NULL;
}
* ioctl()'s on the root directory is the chief method for the daemon to
* generate kernel reactions
*/
-static int autofs4_root_ioctl(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+static int autofs4_root_ioctl_unlocked(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
{
struct autofs_sb_info *sbi = autofs4_sbi(inode->i_sb);
void __user *p = (void __user *)arg;
DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
- cmd,arg,sbi,process_group(current));
+ cmd,arg,sbi,task_pgrp_nr(current));
- if ( _IOC_TYPE(cmd) != _IOC_TYPE(AUTOFS_IOC_FIRST) ||
- _IOC_NR(cmd) - _IOC_NR(AUTOFS_IOC_FIRST) >= AUTOFS_IOC_COUNT )
+ if (_IOC_TYPE(cmd) != _IOC_TYPE(AUTOFS_IOC_FIRST) ||
+ _IOC_NR(cmd) - _IOC_NR(AUTOFS_IOC_FIRST) >= AUTOFS_IOC_COUNT)
return -ENOTTY;
- if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
+ if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN))
return -EPERM;
switch(cmd) {
return autofs4_get_protosubver(sbi, p);
case AUTOFS_IOC_SETTIMEOUT:
return autofs4_get_set_timeout(sbi, p);
-
- case AUTOFS_IOC_TOGGLEREGHOST:
- return autofs4_toggle_reghost(sbi, p);
- case AUTOFS_IOC_ASKREGHOST:
- return autofs4_ask_reghost(sbi, p);
+#ifdef CONFIG_COMPAT
+ case AUTOFS_IOC_SETTIMEOUT32:
+ return autofs4_compat_get_set_timeout(sbi, p);
+#endif
case AUTOFS_IOC_ASKUMOUNT:
- return autofs4_ask_umount(filp->f_vfsmnt, p);
+ return autofs4_ask_umount(filp->f_path.mnt, p);
/* return a single thing to expire */
case AUTOFS_IOC_EXPIRE:
- return autofs4_expire_run(inode->i_sb,filp->f_vfsmnt,sbi, p);
+ return autofs4_expire_run(inode->i_sb,filp->f_path.mnt,sbi, p);
/* same as above, but can send multiple expires through pipe */
case AUTOFS_IOC_EXPIRE_MULTI:
- return autofs4_expire_multi(inode->i_sb,filp->f_vfsmnt,sbi, p);
+ return autofs4_expire_multi(inode->i_sb,filp->f_path.mnt,sbi, p);
default:
return -ENOSYS;
}
}
+
+static long autofs4_root_ioctl(struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct inode *inode = filp->f_dentry->d_inode;
+ return autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);
+}
+
+#ifdef CONFIG_COMPAT
+static long autofs4_root_compat_ioctl(struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ int ret;
+
+ if (cmd == AUTOFS_IOC_READY || cmd == AUTOFS_IOC_FAIL)
+ ret = autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);
+ else
+ ret = autofs4_root_ioctl_unlocked(inode, filp, cmd,
+ (unsigned long)compat_ptr(arg));
+
+ return ret;
+}
+#endif