static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
static int autofs4_root_ioctl(struct inode *, struct file *,unsigned int,unsigned long);
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 *);
+#define TRIGGER_FLAGS (LOOKUP_CONTINUE | LOOKUP_DIRECTORY)
+#define TRIGGER_INTENTS (LOOKUP_OPEN | LOOKUP_CREATE)
+
const struct file_operations autofs4_root_operations = {
.open = dcache_dir_open,
.release = dcache_dir_close,
.read = generic_read_dir,
- .readdir = autofs4_root_readdir,
+ .readdir = dcache_readdir,
+ .llseek = dcache_dir_lseek,
.ioctl = autofs4_root_ioctl,
};
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,
};
const struct inode_operations autofs4_indirect_root_inode_operations = {
.rmdir = autofs4_dir_rmdir,
};
-static int autofs4_root_readdir(struct file *file, void *dirent,
- filldir_t filldir)
-{
- struct autofs_sb_info *sbi = autofs4_sbi(file->f_path.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);
-
- return dcache_readdir(file, dirent, filldir);
-}
-
static int autofs4_dir_open(struct inode *inode, struct file *file)
{
struct dentry *dentry = file->f_path.dentry;
- struct vfsmount *mnt = file->f_path.mnt;
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;
- }
-
- status = -ENOENT;
- if (!d_mountpoint(dentry) && dentry->d_op && dentry->d_op->d_revalidate) {
- struct nameidata nd;
- int empty, ret;
-
- /* In case there are stale directory dentrys from a failed mount */
- spin_lock(&dcache_lock);
- empty = list_empty(&dentry->d_subdirs);
+ /*
+ * 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(&dcache_lock);
+ if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
spin_unlock(&dcache_lock);
-
- if (!empty)
- d_invalidate(dentry);
-
- nd.flags = LOOKUP_DIRECTORY;
- ret = (dentry->d_op->d_revalidate)(dentry, &nd);
-
- if (ret <= 0) {
- if (ret < 0)
- status = ret;
- dcache_dir_close(inode, file);
- goto out;
- }
+ return -ENOENT;
}
+ spin_unlock(&dcache_lock);
- if (d_mountpoint(dentry)) {
- struct file *fp = NULL;
- struct path fp_path = { .dentry = dentry, .mnt = mnt };
-
- path_get(&fp_path);
-
- if (!autofs4_follow_mount(&fp_path.mnt, &fp_path.dentry)) {
- path_put(&fp_path);
- dcache_dir_close(inode, file);
- goto out;
- }
-
- fp = dentry_open(fp_path.dentry, fp_path.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;
-}
-
-static int autofs4_dir_close(struct inode *inode, struct file *file)
-{
- struct dentry *dentry = file->f_path.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;
- }
- filp_close(fp, current->files);
- }
-out:
- dcache_dir_close(inode, file);
- return status;
-}
-
-static int autofs4_dir_readdir(struct file *file, void *dirent, filldir_t filldir)
-{
- struct dentry *dentry = file->f_path.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;
- }
-
- 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 dcache_dir_open(inode, file);
}
static int try_to_fill_dentry(struct dentry *dentry, int flags)
struct autofs_info *ino = autofs4_dentry_ino(dentry);
int status;
- /* 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);
-
- DPRINTK("expire done status=%d", status);
-
- /*
- * If the directory still exists the mount request must
- * continue otherwise it can't be followed at the right
- * time during the walk.
- */
- status = d_invalidate(dentry);
- if (status != -EBUSY)
- return -EAGAIN;
- }
-
DPRINTK("dentry=%p %.*s ino=%p",
dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
return status;
}
/* Trigger mount for path component or follow link */
- } else if (flags & (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) ||
+ } else if (dentry->d_flags & DCACHE_AUTOFS_PENDING ||
+ flags & (TRIGGER_FLAGS | TRIGGER_INTENTS) ||
current->link_count) {
DPRINTK("waiting for mount name=%.*s",
dentry->d_name.len, dentry->d_name.name);
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)
+ /*
+ * For an expire of a covered direct or offset mount we need
+ * to break out of follow_down() at the autofs mount trigger
+ * (d_mounted--), so we can see the expiring flag, and manage
+ * the blocking and following here until the expire is completed.
+ */
+ if (oz_mode) {
+ spin_lock(&sbi->fs_lock);
+ if (ino->flags & AUTOFS_INF_EXPIRING) {
+ spin_unlock(&sbi->fs_lock);
+ /* Follow down to our covering mount. */
+ if (!follow_down(&nd->path))
+ goto done;
+ goto follow;
+ }
+ spin_unlock(&sbi->fs_lock);
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);
+ /* If an expire request is pending everyone must wait. */
+ autofs4_expire_wait(dentry);
- DPRINTK("request done status=%d", status);
- }
+ /* We trigger a mount for almost all flags */
+ lookup_type = nd->flags & (TRIGGER_FLAGS | TRIGGER_INTENTS);
+ if (!(lookup_type || dentry->d_flags & DCACHE_AUTOFS_PENDING))
+ goto follow;
/*
- * 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 the dentry contains directories then it is an autofs
+ * multi-mount with no root mount offset. So don't try to
+ * mount it again.
*/
spin_lock(&dcache_lock);
- if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
+ if (dentry->d_flags & DCACHE_AUTOFS_PENDING ||
+ (!d_mountpoint(dentry) && __simple_empty(dentry))) {
spin_unlock(&dcache_lock);
status = try_to_fill_dentry(dentry, 0);
if (status)
goto out_error;
- /*
- * 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.
- */
- if (d_mountpoint(dentry)) {
- if (!autofs4_follow_mount(&nd->path.mnt,
- &nd->path.dentry)) {
- status = -ENOENT;
- goto out_error;
- }
- }
-
- goto done;
+ goto follow;
}
spin_unlock(&dcache_lock);
+follow:
+ /*
+ * If there is no root mount it must be an autofs
+ * multi-mount with no root offset so we don't need
+ * to follow it.
+ */
+ if (d_mountpoint(dentry)) {
+ if (!autofs4_follow_mount(&nd->path)) {
+ status = -ENOENT;
+ goto out_error;
+ }
+ }
done:
return NULL;
int status = 1;
/* Pending dentry */
+ spin_lock(&sbi->fs_lock);
if (autofs4_ispending(dentry)) {
/* The daemon never causes a mount to trigger */
+ spin_unlock(&sbi->fs_lock);
+
if (oz_mode)
return 1;
/*
+ * If the directory has gone away due to an expire
+ * we have been called as ->d_revalidate() and so
+ * we need to return false and proceed to ->lookup().
+ */
+ if (autofs4_expire_wait(dentry) == -EAGAIN)
+ return 0;
+
+ /*
* A zero status is success otherwise we have a
* negative error code.
*/
if (status == 0)
return 1;
- /*
- * A status of EAGAIN here means that the dentry has gone
- * away while waiting for an expire to complete. If we are
- * racing with expire lookup will wait for it so this must
- * be a revalidate and we need to send it to lookup.
- */
- if (status == -EAGAIN)
- return 0;
-
return status;
}
+ spin_unlock(&sbi->fs_lock);
/* Negative dentry.. invalidate if "old" */
if (dentry->d_inode == NULL)
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;
}
/* For dentries of directories in the root dir */
-static struct dentry_operations autofs4_root_dentry_operations = {
+static const struct dentry_operations autofs4_root_dentry_operations = {
.d_revalidate = autofs4_revalidate,
.d_release = autofs4_dentry_release,
};
/* For other dentries */
-static struct dentry_operations autofs4_dentry_operations = {
+static const struct dentry_operations autofs4_dentry_operations = {
.d_revalidate = autofs4_revalidate,
.d_release = autofs4_dentry_release,
};
DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
current->pid, task_pgrp_nr(current), sbi->catatonic, oz_mode);
- expiring = autofs4_lookup_expiring(sbi, dentry->d_parent, &dentry->d_name);
- if (expiring) {
- /*
- * 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, so just wait for it.
- */
- ino = autofs4_dentry_ino(expiring);
- while (ino && (ino->flags & AUTOFS_INF_EXPIRING)) {
- DPRINTK("wait for incomplete expire %p name=%.*s",
- expiring, expiring->d_name.len,
- expiring->d_name.name);
- autofs4_wait(sbi, expiring, NFY_NONE);
- DPRINTK("request completed");
- }
- spin_lock(&sbi->lookup_lock);
- if (!list_empty(&ino->expiring))
- list_del_init(&ino->expiring);
- spin_unlock(&sbi->lookup_lock);
- dput(expiring);
- }
-
unhashed = autofs4_lookup_active(sbi, dentry->d_parent, &dentry->d_name);
if (unhashed)
dentry = unhashed;
}
if (!oz_mode) {
+ mutex_unlock(&dir->i_mutex);
+ expiring = autofs4_lookup_expiring(sbi,
+ dentry->d_parent,
+ &dentry->d_name);
+ if (expiring) {
+ /*
+ * 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, so just wait for it.
+ */
+ ino = autofs4_dentry_ino(expiring);
+ autofs4_expire_wait(expiring);
+ spin_lock(&sbi->lookup_lock);
+ if (!list_empty(&ino->expiring))
+ list_del_init(&ino->expiring);
+ spin_unlock(&sbi->lookup_lock);
+ dput(expiring);
+ }
+
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_AUTOFS_PENDING;
spin_unlock(&dentry->d_lock);
- }
-
- if (dentry->d_op && dentry->d_op->d_revalidate) {
- mutex_unlock(&dir->i_mutex);
- (dentry->d_op->d_revalidate)(dentry, nd);
+ if (dentry->d_op && dentry->d_op->d_revalidate)
+ (dentry->d_op->d_revalidate)(dentry, nd);
mutex_lock(&dir->i_mutex);
}
list_del_init(&ino->active);
spin_unlock(&sbi->lookup_lock);
+ ino->size = strlen(symname);
cp = kmalloc(ino->size + 1, GFP_KERNEL);
if (!cp) {
if (!dentry->d_fsdata)
atomic_inc(&p_ino->count);
ino->inode = inode;
- ino->size = strlen(symname);
ino->u.symlink = cp;
dir->i_mtime = CURRENT_TIME;
}
/*
- * 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.
*/
static inline int autofs4_ask_umount(struct vfsmount *mnt, int __user *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);
-
case AUTOFS_IOC_ASKUMOUNT:
return autofs4_ask_umount(filp->f_path.mnt, p);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff