示例#1
0
int
tmpfs_reclaim(struct vop_reclaim_args *v)
{
	struct vnode *vp = v->a_vp;

	struct tmpfs_mount *tmp;
	struct tmpfs_node *node;

	node = VP_TO_TMPFS_NODE(vp);
	tmp = VFS_TO_TMPFS(vp->v_mount);

	vnode_destroy_vobject(vp);
	cache_purge(vp);

	TMPFS_NODE_LOCK(node);
	TMPFS_ASSERT_ELOCKED(node);
	tmpfs_free_vp(vp);

	/* If the node referenced by this vnode was deleted by the user,
	 * we must free its associated data structures (now that the vnode
	 * is being reclaimed). */
	if (node->tn_links == 0 &&
	    (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
		node->tn_vpstate = TMPFS_VNODE_DOOMED;
		TMPFS_NODE_UNLOCK(node);
		tmpfs_free_node(tmp, node);
	} else
		TMPFS_NODE_UNLOCK(node);

	MPASS(vp->v_data == NULL);
	return 0;
}
示例#2
0
/*
 * Frees a directory entry.  It is the caller's responsibility to destroy
 * the node referenced by it if needed.
 *
 * The link count of node is decreased by one to reflect the removal of an
 * object that referenced it.  This only happens if 'node_exists' is true;
 * otherwise the function will not access the node referred to by the
 * directory entry, as it may already have been released from the outside.
 */
void
tmpfs_free_dirent(struct tmpfs_mount *tmp, struct tmpfs_dirent *de)
{
	struct tmpfs_node *node;

	node = de->td_node;

	TMPFS_NODE_LOCK(node);
	TMPFS_ASSERT_ELOCKED(node);
	KKASSERT(node->tn_links > 0);
	node->tn_links--;
	TMPFS_NODE_UNLOCK(node);

	kfree(de->td_name, tmp->tm_name_zone);
	de->td_namelen = 0;
	de->td_name = NULL;
	de->td_node = NULL;
	objcache_put(tmp->tm_dirent_pool, de);
}
示例#3
0
static int
tmpfs_nrmdir(struct vop_nrmdir_args *v)
{
	struct vnode *dvp = v->a_dvp;
	struct namecache *ncp = v->a_nch->ncp;
	struct vnode *vp;
	struct tmpfs_dirent *de;
	struct tmpfs_mount *tmp;
	struct tmpfs_node *dnode;
	struct tmpfs_node *node;
	struct mount *mp;
	int error;

	mp = dvp->v_mount;

	/*
	 * We have to acquire the vp from v->a_nch because we will likely
	 * unresolve the namecache entry, and a vrele/vput is needed to
	 * trigger the tmpfs_inactive/tmpfs_reclaim sequence.
	 *
	 * We have to use vget to clear any inactive state on the vnode,
	 * otherwise the vnode may remain inactive and thus tmpfs_inactive
	 * will not get called when we release it.
	 */
	error = cache_vget(v->a_nch, v->a_cred, LK_SHARED, &vp);
	KKASSERT(error == 0);
	vn_unlock(vp);

	/*
	 * Prevalidate so we don't hit an assertion later
	 */
	if (vp->v_type != VDIR) {
		error = ENOTDIR;
		goto out;
	}

	tmp = VFS_TO_TMPFS(dvp->v_mount);
	dnode = VP_TO_TMPFS_DIR(dvp);
	node = VP_TO_TMPFS_DIR(vp);

	/*
	 * Directories with more than two entries ('.' and '..') cannot
	 * be removed.
	 */
	if (node->tn_size > 0) {
		error = ENOTEMPTY;
		goto out;
	}

	if ((dnode->tn_flags & APPEND)
	    || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
		error = EPERM;
		goto out;
	}

	/*
	 * This invariant holds only if we are not trying to
	 * remove "..".  We checked for that above so this is safe now.
	 */
	KKASSERT(node->tn_dir.tn_parent == dnode);

	/*
	 * Get the directory entry associated with node (vp).  This
	 * was filled by tmpfs_lookup while looking up the entry.
	 */
	TMPFS_NODE_LOCK(dnode);
	de = tmpfs_dir_lookup(dnode, node, ncp);
	KKASSERT(TMPFS_DIRENT_MATCHES(de, ncp->nc_name, ncp->nc_nlen));

	/* Check flags to see if we are allowed to remove the directory. */
	if ((dnode->tn_flags & APPEND) ||
	    node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) {
		error = EPERM;
		TMPFS_NODE_UNLOCK(dnode);
		goto out;
	}

	/* Detach the directory entry from the directory (dnode). */
	tmpfs_dir_detach(dnode, de);
	TMPFS_NODE_UNLOCK(dnode);

	/* No vnode should be allocated for this entry from this point */
	TMPFS_NODE_LOCK(dnode);
	TMPFS_ASSERT_ELOCKED(dnode);
	TMPFS_NODE_LOCK(node);
	TMPFS_ASSERT_ELOCKED(node);

	/*
	 * Must set parent linkage to NULL (tested by ncreate to disallow
	 * the creation of new files/dirs in a deleted directory)
	 */
	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
			   TMPFS_NODE_MODIFIED;

	dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
			    TMPFS_NODE_MODIFIED;

	TMPFS_NODE_UNLOCK(node);
	TMPFS_NODE_UNLOCK(dnode);

	/* Free the directory entry we just deleted.  Note that the node
	 * referred by it will not be removed until the vnode is really
	 * reclaimed. */
	tmpfs_free_dirent(tmp, de);

	/* Release the deleted vnode (will destroy the node, notify
	 * interested parties and clean it from the cache). */

	TMPFS_NODE_LOCK(dnode);
	dnode->tn_status |= TMPFS_NODE_CHANGED;
	TMPFS_NODE_UNLOCK(dnode);
	tmpfs_update(dvp);

	cache_unlink(v->a_nch);
	tmpfs_knote(dvp, NOTE_WRITE | NOTE_LINK);
	error = 0;

out:
	vrele(vp);

	return error;
}
示例#4
0
static int
tmpfs_rmdir(struct vop_rmdir_args *v)
{
	struct vnode *dvp = v->a_dvp;
	struct vnode *vp = v->a_vp;

	int error;
	struct tmpfs_dirent *de;
	struct tmpfs_mount *tmp;
	struct tmpfs_node *dnode;
	struct tmpfs_node *node;

	MPASS(VOP_ISLOCKED(dvp));
	MPASS(VOP_ISLOCKED(vp));

	tmp = VFS_TO_TMPFS(dvp->v_mount);
	dnode = VP_TO_TMPFS_DIR(dvp);
	node = VP_TO_TMPFS_DIR(vp);

	/* Directories with more than two entries ('.' and '..') cannot be
	 * removed. */
	 if (node->tn_size > 0) {
		 error = ENOTEMPTY;
		 goto out;
	 }

	if ((dnode->tn_flags & APPEND)
	    || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
		error = EPERM;
		goto out;
	}

	/* This invariant holds only if we are not trying to remove "..".
	  * We checked for that above so this is safe now. */
	MPASS(node->tn_dir.tn_parent == dnode);

	/* Get the directory entry associated with node (vp).  This was
	 * filled by tmpfs_lookup while looking up the entry. */
	de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
	MPASS(TMPFS_DIRENT_MATCHES(de,
	    v->a_cnp->cn_nameptr,
	    v->a_cnp->cn_namelen));

	/* Check flags to see if we are allowed to remove the directory. */
	if (dnode->tn_flags & APPEND
		|| node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) {
		error = EPERM;
		goto out;
	}


	/* Detach the directory entry from the directory (dnode). */
	tmpfs_dir_detach(dvp, de);
	if (v->a_cnp->cn_flags & DOWHITEOUT)
		tmpfs_dir_whiteout_add(dvp, v->a_cnp);

	/* No vnode should be allocated for this entry from this point */
	TMPFS_NODE_LOCK(node);
	TMPFS_ASSERT_ELOCKED(node);
	node->tn_links--;
	node->tn_dir.tn_parent = NULL;
	node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \
	    TMPFS_NODE_MODIFIED;

	TMPFS_NODE_UNLOCK(node);

	TMPFS_NODE_LOCK(dnode);
	TMPFS_ASSERT_ELOCKED(dnode);
	dnode->tn_links--;
	dnode->tn_status |= TMPFS_NODE_ACCESSED | \
	    TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
	TMPFS_NODE_UNLOCK(dnode);

	cache_purge(dvp);
	cache_purge(vp);

	/* Free the directory entry we just deleted.  Note that the node
	 * referred by it will not be removed until the vnode is really
	 * reclaimed. */
	tmpfs_free_dirent(tmp, de, TRUE);

	/* Release the deleted vnode (will destroy the node, notify
	 * interested parties and clean it from the cache). */

	dnode->tn_status |= TMPFS_NODE_CHANGED;
	tmpfs_update(dvp);

	error = 0;

out:
	return error;
}
示例#5
0
/*
 * Destroys the node pointed to by node from the file system 'tmp'.
 * If the node does not belong to the given mount point, the results are
 * unpredicted.
 *
 * If the node references a directory; no entries are allowed because
 * their removal could need a recursive algorithm, something forbidden in
 * kernel space.  Furthermore, there is not need to provide such
 * functionality (recursive removal) because the only primitives offered
 * to the user are the removal of empty directories and the deletion of
 * individual files.
 *
 * Note that nodes are not really deleted; in fact, when a node has been
 * allocated, it cannot be deleted during the whole life of the file
 * system.  Instead, they are moved to the available list and remain there
 * until reused.
 *
 * A caller must have TMPFS_NODE_LOCK(node) and this function unlocks it.
 */
void
tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
{
	vm_pindex_t pages = 0;

#ifdef INVARIANTS
	TMPFS_ASSERT_ELOCKED(node);
	KKASSERT(node->tn_vnode == NULL);
	KKASSERT((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0);
#endif

	TMPFS_LOCK(tmp);
	LIST_REMOVE(node, tn_entries);
	tmp->tm_nodes_inuse--;
	TMPFS_UNLOCK(tmp);
	TMPFS_NODE_UNLOCK(node);  /* Caller has this lock */

	switch (node->tn_type) {
	case VNON:
		/* Do not do anything.  VNON is provided to let the
		 * allocation routine clean itself easily by avoiding
		 * duplicating code in it. */
		/* FALLTHROUGH */
	case VBLK:
		/* FALLTHROUGH */
	case VCHR:
		/* FALLTHROUGH */
		break;
	case VDIR:
		/*
		 * The parent link can be NULL if this is the root
		 * node or if it is a directory node that was rmdir'd.
		 *
		 * XXX what if node is a directory which still contains
		 * directory entries (e.g. due to a forced umount) ?
		 */
		node->tn_size = 0;
		KKASSERT(node->tn_dir.tn_parent == NULL);

		/*
		 * If the root node is being destroyed don't leave a
		 * dangling pointer in tmpfs_mount.
		 */
		if (node == tmp->tm_root)
			tmp->tm_root = NULL;
		break;
	case VFIFO:
		/* FALLTHROUGH */
	case VSOCK:
		break;

	case VLNK:
		kfree(node->tn_link, tmp->tm_name_zone);
		node->tn_link = NULL;
		node->tn_size = 0;
		break;

	case VREG:
		if (node->tn_reg.tn_aobj != NULL)
			vm_object_deallocate(node->tn_reg.tn_aobj);
		node->tn_reg.tn_aobj = NULL;
		pages = node->tn_reg.tn_aobj_pages;
		break;

	default:
		panic("tmpfs_free_node: type %p %d", node, (int)node->tn_type);
	}

	/*
	 * Clean up fields for the next allocation.  The objcache only ctors
	 * new allocations.
	 */
	tmpfs_node_ctor(node, NULL, 0);
	objcache_put(tmp->tm_node_pool, node);
	/* node is now invalid */

	if (pages)
		atomic_add_long(&tmp->tm_pages_used, -(long)pages);
}