1 /* $NetBSD: tmpfs_subr.c,v 1.35 2007/07/09 21:10:50 ad Exp $ */
4 * Copyright (c) 2005 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
34 * Efficient memory file system supporting functions.
37 #include <sys/kernel.h>
38 #include <sys/param.h>
39 #include <sys/namei.h>
43 #include <sys/systm.h>
44 #include <sys/vnode.h>
45 #include <sys/vmmeter.h>
48 #include <vm/vm_object.h>
49 #include <vm/vm_page.h>
50 #include <vm/vm_pager.h>
51 #include <vm/vm_extern.h>
53 #include <vfs/tmpfs/tmpfs.h>
54 #include <vfs/tmpfs/tmpfs_vnops.h>
56 static ino_t tmpfs_fetch_ino(struct tmpfs_mount *);
58 static int tmpfs_dirtree_compare(struct tmpfs_dirent *a,
59 struct tmpfs_dirent *b);
60 RB_GENERATE(tmpfs_dirtree, tmpfs_dirent, rb_node, tmpfs_dirtree_compare);
62 static int tmpfs_dirtree_compare_cookie(struct tmpfs_dirent *a,
63 struct tmpfs_dirent *b);
64 RB_GENERATE(tmpfs_dirtree_cookie, tmpfs_dirent,
65 rb_cookienode, tmpfs_dirtree_compare_cookie);
68 /* --------------------------------------------------------------------- */
71 * Allocates a new node of type 'type' inside the 'tmp' mount point, with
72 * its owner set to 'uid', its group to 'gid' and its mode set to 'mode',
73 * using the credentials of the process 'p'.
75 * If the node type is set to 'VDIR', then the parent parameter must point
76 * to the parent directory of the node being created. It may only be NULL
77 * while allocating the root node.
79 * If the node type is set to 'VBLK' or 'VCHR', then the rdev parameter
80 * specifies the device the node represents.
82 * If the node type is set to 'VLNK', then the parameter target specifies
83 * the file name of the target file for the symbolic link that is being
86 * Note that new nodes are retrieved from the available list if it has
87 * items or, if it is empty, from the node pool as long as there is enough
88 * space to create them.
90 * Returns zero on success or an appropriate error code on failure.
93 tmpfs_alloc_node(struct tmpfs_mount *tmp, enum vtype type,
94 uid_t uid, gid_t gid, mode_t mode,
95 char *target, int rmajor, int rminor,
96 struct tmpfs_node **node)
98 struct tmpfs_node *nnode;
102 KKASSERT(IFF(type == VLNK, target != NULL));
103 KKASSERT(IFF(type == VBLK || type == VCHR, rmajor != VNOVAL));
105 if (tmp->tm_nodes_inuse >= tmp->tm_nodes_max)
108 nnode = objcache_get(tmp->tm_node_pool, M_WAITOK | M_NULLOK);
112 /* Generic initialization. */
113 nnode->tn_type = type;
115 nnode->tn_ctime = nnode->tn_mtime = nnode->tn_atime
117 nnode->tn_ctimensec = nnode->tn_mtimensec = nnode->tn_atimensec
121 nnode->tn_mode = mode;
122 nnode->tn_id = tmpfs_fetch_ino(tmp);
123 nnode->tn_advlock.init_done = 0;
124 KKASSERT(nnode->tn_links == 0);
126 /* Type-specific initialization. */
127 switch (nnode->tn_type) {
130 rdev = makeudev(rmajor, rminor);
131 if (rdev == NOUDEV) {
132 objcache_put(tmp->tm_node_pool, nnode);
135 nnode->tn_rdev = rdev;
139 RB_INIT(&nnode->tn_dir.tn_dirtree);
140 RB_INIT(&nnode->tn_dir.tn_cookietree);
150 nnode->tn_size = strlen(target);
151 nnode->tn_link = kmalloc(nnode->tn_size + 1, tmp->tm_name_zone,
152 M_WAITOK | M_NULLOK);
153 if (nnode->tn_link == NULL) {
154 objcache_put(tmp->tm_node_pool, nnode);
157 bcopy(target, nnode->tn_link, nnode->tn_size);
158 nnode->tn_link[nnode->tn_size] = '\0';
162 nnode->tn_reg.tn_aobj =
163 swap_pager_alloc(NULL, 0, VM_PROT_DEFAULT, 0);
164 nnode->tn_reg.tn_aobj_pages = 0;
169 panic("tmpfs_alloc_node: type %p %d", nnode, (int)nnode->tn_type);
172 TMPFS_NODE_LOCK(nnode);
174 LIST_INSERT_HEAD(&tmp->tm_nodes_used, nnode, tn_entries);
175 tmp->tm_nodes_inuse++;
177 TMPFS_NODE_UNLOCK(nnode);
183 /* --------------------------------------------------------------------- */
186 * Destroys the node pointed to by node from the file system 'tmp'.
187 * If the node does not belong to the given mount point, the results are
190 * If the node references a directory; no entries are allowed because
191 * their removal could need a recursive algorithm, something forbidden in
192 * kernel space. Furthermore, there is not need to provide such
193 * functionality (recursive removal) because the only primitives offered
194 * to the user are the removal of empty directories and the deletion of
197 * Note that nodes are not really deleted; in fact, when a node has been
198 * allocated, it cannot be deleted during the whole life of the file
199 * system. Instead, they are moved to the available list and remain there
202 * A caller must have TMPFS_NODE_LOCK(node) and this function unlocks it.
205 tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
207 vm_pindex_t pages = 0;
210 TMPFS_ASSERT_ELOCKED(node);
211 KKASSERT(node->tn_vnode == NULL);
212 KKASSERT((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0);
216 LIST_REMOVE(node, tn_entries);
217 tmp->tm_nodes_inuse--;
219 TMPFS_NODE_UNLOCK(node); /* Caller has this lock */
221 switch (node->tn_type) {
223 /* Do not do anything. VNON is provided to let the
224 * allocation routine clean itself easily by avoiding
225 * duplicating code in it. */
234 * The parent link can be NULL if this is the root
235 * node or if it is a directory node that was rmdir'd.
237 * XXX what if node is a directory which still contains
238 * directory entries (e.g. due to a forced umount) ?
241 KKASSERT(node->tn_dir.tn_parent == NULL);
244 * If the root node is being destroyed don't leave a
245 * dangling pointer in tmpfs_mount.
247 if (node == tmp->tm_root)
256 kfree(node->tn_link, tmp->tm_name_zone);
257 node->tn_link = NULL;
262 if (node->tn_reg.tn_aobj != NULL)
263 vm_object_deallocate(node->tn_reg.tn_aobj);
264 node->tn_reg.tn_aobj = NULL;
265 pages = node->tn_reg.tn_aobj_pages;
269 panic("tmpfs_free_node: type %p %d", node, (int)node->tn_type);
273 * Clean up fields for the next allocation. The objcache only ctors
276 tmpfs_node_ctor(node, NULL, 0);
277 objcache_put(tmp->tm_node_pool, node);
278 /* node is now invalid */
281 tmp->tm_pages_used -= pages;
285 /* --------------------------------------------------------------------- */
288 * Allocates a new directory entry for the node node with a name of name.
289 * The new directory entry is returned in *de.
291 * The link count of node is increased by one to reflect the new object
294 * Returns zero on success or an appropriate error code on failure.
297 tmpfs_alloc_dirent(struct tmpfs_mount *tmp, struct tmpfs_node *node,
298 const char *name, uint16_t len, struct tmpfs_dirent **de)
300 struct tmpfs_dirent *nde;
302 nde = objcache_get(tmp->tm_dirent_pool, M_WAITOK);
303 nde->td_name = kmalloc(len + 1, tmp->tm_name_zone, M_WAITOK | M_NULLOK);
304 if (nde->td_name == NULL) {
305 objcache_put(tmp->tm_dirent_pool, nde);
309 nde->td_namelen = len;
310 bcopy(name, nde->td_name, len);
311 nde->td_name[len] = '\0';
315 TMPFS_NODE_LOCK(node);
317 TMPFS_NODE_UNLOCK(node);
324 /* --------------------------------------------------------------------- */
327 * Frees a directory entry. It is the caller's responsibility to destroy
328 * the node referenced by it if needed.
330 * The link count of node is decreased by one to reflect the removal of an
331 * object that referenced it. This only happens if 'node_exists' is true;
332 * otherwise the function will not access the node referred to by the
333 * directory entry, as it may already have been released from the outside.
336 tmpfs_free_dirent(struct tmpfs_mount *tmp, struct tmpfs_dirent *de)
338 struct tmpfs_node *node;
342 TMPFS_NODE_LOCK(node);
343 TMPFS_ASSERT_ELOCKED(node);
344 KKASSERT(node->tn_links > 0);
346 TMPFS_NODE_UNLOCK(node);
348 kfree(de->td_name, tmp->tm_name_zone);
352 objcache_put(tmp->tm_dirent_pool, de);
355 /* --------------------------------------------------------------------- */
358 * Allocates a new vnode for the node node or returns a new reference to
359 * an existing one if the node had already a vnode referencing it. The
360 * resulting locked vnode is returned in *vpp.
362 * Returns zero on success or an appropriate error code on failure.
365 tmpfs_alloc_vp(struct mount *mp, struct tmpfs_node *node, int lkflag,
373 * Interlocked extraction from node. This can race many things.
374 * We have to get a soft reference on the vnode while we hold
375 * the node locked, then acquire it properly and check for races.
377 TMPFS_NODE_LOCK(node);
378 if ((vp = node->tn_vnode) != NULL) {
379 KKASSERT((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0);
381 TMPFS_NODE_UNLOCK(node);
383 if (vget(vp, lkflag | LK_EXCLUSIVE) != 0) {
387 if (node->tn_vnode != vp) {
398 * This should never happen.
400 if (node->tn_vpstate & TMPFS_VNODE_DOOMED) {
401 TMPFS_NODE_UNLOCK(node);
407 * Interlock against other calls to tmpfs_alloc_vp() trying to
408 * allocate and assign a vp to node.
410 if (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) {
411 node->tn_vpstate |= TMPFS_VNODE_WANT;
412 error = tsleep(&node->tn_vpstate, PINTERLOCKED | PCATCH,
413 "tmpfs_alloc_vp", 0);
414 TMPFS_NODE_UNLOCK(node);
419 node->tn_vpstate |= TMPFS_VNODE_ALLOCATING;
420 TMPFS_NODE_UNLOCK(node);
423 * Allocate a new vnode (may block). The ALLOCATING flag should
424 * prevent a race against someone else assigning node->tn_vnode.
426 error = getnewvnode(VT_TMPFS, mp, &vp, VLKTIMEOUT, LK_CANRECURSE);
430 KKASSERT(node->tn_vnode == NULL);
431 KKASSERT(vp != NULL);
433 vp->v_type = node->tn_type;
435 /* Type-specific initialization. */
436 switch (node->tn_type) {
444 vinitvmio(vp, node->tn_size, TMPFS_BLKMASK, -1);
449 vp->v_ops = &mp->mnt_vn_fifo_ops;
455 panic("tmpfs_alloc_vp: type %p %d", node, (int)node->tn_type);
460 TMPFS_NODE_LOCK(node);
462 KKASSERT(node->tn_vpstate & TMPFS_VNODE_ALLOCATING);
463 node->tn_vpstate &= ~TMPFS_VNODE_ALLOCATING;
466 if (node->tn_vpstate & TMPFS_VNODE_WANT) {
467 node->tn_vpstate &= ~TMPFS_VNODE_WANT;
468 TMPFS_NODE_UNLOCK(node);
469 wakeup(&node->tn_vpstate);
471 TMPFS_NODE_UNLOCK(node);
477 KKASSERT(IFF(error == 0, *vpp != NULL && vn_islocked(*vpp)));
479 TMPFS_NODE_LOCK(node);
480 KKASSERT(*vpp == node->tn_vnode);
481 TMPFS_NODE_UNLOCK(node);
487 /* --------------------------------------------------------------------- */
490 * Destroys the association between the vnode vp and the node it
494 tmpfs_free_vp(struct vnode *vp)
496 struct tmpfs_node *node;
498 node = VP_TO_TMPFS_NODE(vp);
500 TMPFS_NODE_LOCK(node);
501 KKASSERT(lockcount(TMPFS_NODE_MTX(node)) > 0);
502 node->tn_vnode = NULL;
504 TMPFS_NODE_UNLOCK(node);
507 /* --------------------------------------------------------------------- */
510 * Allocates a new file of type 'type' and adds it to the parent directory
511 * 'dvp'; this addition is done using the component name given in 'cnp'.
512 * The ownership of the new file is automatically assigned based on the
513 * credentials of the caller (through 'cnp'), the group is set based on
514 * the parent directory and the mode is determined from the 'vap' argument.
515 * If successful, *vpp holds a vnode to the newly created file and zero
516 * is returned. Otherwise *vpp is NULL and the function returns an
517 * appropriate error code.
520 tmpfs_alloc_file(struct vnode *dvp, struct vnode **vpp, struct vattr *vap,
521 struct namecache *ncp, struct ucred *cred, char *target)
524 struct tmpfs_dirent *de;
525 struct tmpfs_mount *tmp;
526 struct tmpfs_node *dnode;
527 struct tmpfs_node *node;
529 tmp = VFS_TO_TMPFS(dvp->v_mount);
530 dnode = VP_TO_TMPFS_DIR(dvp);
534 * If the directory was removed but a process was CD'd into it,
535 * we do not allow any more file/dir creation within it. Otherwise
536 * we will lose track of it.
538 KKASSERT(dnode->tn_type == VDIR);
539 if (dnode != tmp->tm_root && dnode->tn_dir.tn_parent == NULL)
543 * Make sure the link count does not overflow.
545 if (vap->va_type == VDIR && dnode->tn_links >= LINK_MAX)
548 /* Allocate a node that represents the new file. */
549 error = tmpfs_alloc_node(tmp, vap->va_type, cred->cr_uid,
550 dnode->tn_gid, vap->va_mode, target,
551 vap->va_rmajor, vap->va_rminor, &node);
554 TMPFS_NODE_LOCK(node);
556 /* Allocate a directory entry that points to the new file. */
557 error = tmpfs_alloc_dirent(tmp, node, ncp->nc_name, ncp->nc_nlen, &de);
559 tmpfs_free_node(tmp, node);
564 /* Allocate a vnode for the new file. */
565 error = tmpfs_alloc_vp(dvp->v_mount, node, LK_EXCLUSIVE, vpp);
567 tmpfs_free_dirent(tmp, de);
568 tmpfs_free_node(tmp, node);
574 * Now that all required items are allocated, we can proceed to
575 * insert the new node into the directory, an operation that
578 tmpfs_dir_attach(dnode, de);
579 TMPFS_NODE_UNLOCK(node);
584 /* --------------------------------------------------------------------- */
587 * Attaches the directory entry de to the directory represented by dnode.
588 * Note that this does not change the link count of the node pointed by
589 * the directory entry, as this is done by tmpfs_alloc_dirent.
592 tmpfs_dir_attach(struct tmpfs_node *dnode, struct tmpfs_dirent *de)
594 struct tmpfs_node *node = de->td_node;
596 TMPFS_NODE_LOCK(dnode);
597 if (node && node->tn_type == VDIR) {
598 TMPFS_NODE_LOCK(node);
600 node->tn_status |= TMPFS_NODE_CHANGED;
601 node->tn_dir.tn_parent = dnode;
603 TMPFS_NODE_UNLOCK(node);
605 RB_INSERT(tmpfs_dirtree, &dnode->tn_dir.tn_dirtree, de);
606 RB_INSERT(tmpfs_dirtree_cookie, &dnode->tn_dir.tn_cookietree, de);
607 dnode->tn_size += sizeof(struct tmpfs_dirent);
608 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
610 TMPFS_NODE_UNLOCK(dnode);
613 /* --------------------------------------------------------------------- */
616 * Detaches the directory entry de from the directory represented by dnode.
617 * Note that this does not change the link count of the node pointed by
618 * the directory entry, as this is done by tmpfs_free_dirent.
621 tmpfs_dir_detach(struct tmpfs_node *dnode, struct tmpfs_dirent *de)
623 struct tmpfs_node *node = de->td_node;
625 TMPFS_NODE_LOCK(dnode);
626 RB_REMOVE(tmpfs_dirtree, &dnode->tn_dir.tn_dirtree, de);
627 RB_REMOVE(tmpfs_dirtree_cookie, &dnode->tn_dir.tn_cookietree, de);
628 dnode->tn_size -= sizeof(struct tmpfs_dirent);
629 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
631 TMPFS_NODE_UNLOCK(dnode);
634 * Clean out the tn_parent pointer immediately when removing a
637 * Removal of the parent linkage also cleans out the extra tn_links
638 * count we had on both node and dnode.
640 * node can be NULL (typ during a forced umount), in which case
641 * the mount code is dealing with the linkages from a linked list
644 if (node && node->tn_type == VDIR && node->tn_dir.tn_parent) {
645 TMPFS_NODE_LOCK(dnode);
646 TMPFS_NODE_LOCK(node);
647 KKASSERT(node->tn_dir.tn_parent == dnode);
650 node->tn_dir.tn_parent = NULL;
651 TMPFS_NODE_UNLOCK(node);
652 TMPFS_NODE_UNLOCK(dnode);
656 /* --------------------------------------------------------------------- */
659 * Looks for a directory entry in the directory represented by node.
660 * 'ncp' describes the name of the entry to look for. Note that the .
661 * and .. components are not allowed as they do not physically exist
662 * within directories.
664 * Returns a pointer to the entry when found, otherwise NULL.
666 * Caller must hold the node locked (shared ok)
668 struct tmpfs_dirent *
669 tmpfs_dir_lookup(struct tmpfs_node *node, struct tmpfs_node *f,
670 struct namecache *ncp)
672 struct tmpfs_dirent *de;
673 int len = ncp->nc_nlen;
674 struct tmpfs_dirent wanted;
676 wanted.td_namelen = len;
677 wanted.td_name = ncp->nc_name;
679 TMPFS_VALIDATE_DIR(node);
681 de = RB_FIND(tmpfs_dirtree, &node->tn_dir.tn_dirtree, &wanted);
683 KKASSERT(f == NULL || f == de->td_node);
688 /* --------------------------------------------------------------------- */
691 * Helper function for tmpfs_readdir. Creates a '.' entry for the given
692 * directory and returns it in the uio space. The function returns 0
693 * on success, -1 if there was not enough space in the uio structure to
694 * hold the directory entry or an appropriate error code if another
698 tmpfs_dir_getdotdent(struct tmpfs_node *node, struct uio *uio)
704 TMPFS_VALIDATE_DIR(node);
705 KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOT);
707 dent.d_ino = node->tn_id;
708 dent.d_type = DT_DIR;
710 dent.d_name[0] = '.';
711 dent.d_name[1] = '\0';
712 dirsize = _DIRENT_DIRSIZ(&dent);
714 if (dirsize > uio->uio_resid)
717 error = uiomove((caddr_t)&dent, dirsize, uio);
719 uio->uio_offset = TMPFS_DIRCOOKIE_DOTDOT;
724 /* --------------------------------------------------------------------- */
727 * Helper function for tmpfs_readdir. Creates a '..' entry for the given
728 * directory and returns it in the uio space. The function returns 0
729 * on success, -1 if there was not enough space in the uio structure to
730 * hold the directory entry or an appropriate error code if another
734 tmpfs_dir_getdotdotdent(struct tmpfs_mount *tmp, struct tmpfs_node *node,
741 TMPFS_VALIDATE_DIR(node);
742 KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOTDOT);
744 if (node->tn_dir.tn_parent) {
745 TMPFS_NODE_LOCK(node);
746 if (node->tn_dir.tn_parent)
747 dent.d_ino = node->tn_dir.tn_parent->tn_id;
749 dent.d_ino = tmp->tm_root->tn_id;
750 TMPFS_NODE_UNLOCK(node);
752 dent.d_ino = tmp->tm_root->tn_id;
755 dent.d_type = DT_DIR;
757 dent.d_name[0] = '.';
758 dent.d_name[1] = '.';
759 dent.d_name[2] = '\0';
760 dirsize = _DIRENT_DIRSIZ(&dent);
762 if (dirsize > uio->uio_resid)
765 error = uiomove((caddr_t)&dent, dirsize, uio);
767 struct tmpfs_dirent *de;
769 de = RB_MIN(tmpfs_dirtree_cookie,
770 &node->tn_dir.tn_cookietree);
772 uio->uio_offset = TMPFS_DIRCOOKIE_EOF;
774 uio->uio_offset = tmpfs_dircookie(de);
780 /* --------------------------------------------------------------------- */
783 * Lookup a directory entry by its associated cookie.
785 * Must be called with the directory node locked (shared ok)
787 struct lubycookie_info {
789 struct tmpfs_dirent *de;
793 lubycookie_cmp(struct tmpfs_dirent *de, void *arg)
795 struct lubycookie_info *info = arg;
796 off_t cookie = tmpfs_dircookie(de);
798 if (cookie < info->cookie)
800 if (cookie > info->cookie)
806 lubycookie_callback(struct tmpfs_dirent *de, void *arg)
808 struct lubycookie_info *info = arg;
810 if (tmpfs_dircookie(de) == info->cookie) {
817 struct tmpfs_dirent *
818 tmpfs_dir_lookupbycookie(struct tmpfs_node *node, off_t cookie)
820 struct lubycookie_info info;
822 info.cookie = cookie;
824 RB_SCAN(tmpfs_dirtree_cookie, &node->tn_dir.tn_cookietree,
825 lubycookie_cmp, lubycookie_callback, &info);
829 /* --------------------------------------------------------------------- */
832 * Helper function for tmpfs_readdir. Returns as much directory entries
833 * as can fit in the uio space. The read starts at uio->uio_offset.
834 * The function returns 0 on success, -1 if there was not enough space
835 * in the uio structure to hold the directory entry or an appropriate
836 * error code if another error happens.
838 * Caller must hold the node locked (shared ok)
841 tmpfs_dir_getdents(struct tmpfs_node *node, struct uio *uio, off_t *cntp)
845 struct tmpfs_dirent *de;
847 TMPFS_VALIDATE_DIR(node);
850 * Locate the first directory entry we have to return. We have cached
851 * the last readdir in the node, so use those values if appropriate.
852 * Otherwise do a linear scan to find the requested entry.
854 startcookie = uio->uio_offset;
855 KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOT);
856 KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOTDOT);
858 if (startcookie == TMPFS_DIRCOOKIE_EOF)
861 de = tmpfs_dir_lookupbycookie(node, startcookie);
866 * Read as much entries as possible; i.e., until we reach the end of
867 * the directory or we exhaust uio space.
873 /* Create a dirent structure representing the current
874 * tmpfs_node and fill it. */
875 d.d_ino = de->td_node->tn_id;
876 switch (de->td_node->tn_type) {
906 panic("tmpfs_dir_getdents: type %p %d",
907 de->td_node, (int)de->td_node->tn_type);
909 d.d_namlen = de->td_namelen;
910 KKASSERT(de->td_namelen < sizeof(d.d_name));
911 bcopy(de->td_name, d.d_name, d.d_namlen);
912 d.d_name[d.d_namlen] = '\0';
913 reclen = _DIRENT_RECLEN(d.d_namlen);
915 /* Stop reading if the directory entry we are treating is
916 * bigger than the amount of data that can be returned. */
917 if (reclen > uio->uio_resid) {
922 /* Copy the new dirent structure into the output buffer and
923 * advance pointers. */
924 error = uiomove((caddr_t)&d, reclen, uio);
927 de = RB_NEXT(tmpfs_dirtree_cookie,
928 node->tn_dir.tn_cookietree, de);
929 } while (error == 0 && uio->uio_resid > 0 && de != NULL);
931 /* Update the offset and cache. */
933 uio->uio_offset = TMPFS_DIRCOOKIE_EOF;
935 uio->uio_offset = tmpfs_dircookie(de);
941 /* --------------------------------------------------------------------- */
944 * Resizes the aobj associated to the regular file pointed to by vp to
945 * the size newsize. 'vp' must point to a vnode that represents a regular
946 * file. 'newsize' must be positive.
948 * pass trivial as 1 when buf content will be overwritten, otherwise set 0
951 * Returns zero on success or an appropriate error code on failure.
954 tmpfs_reg_resize(struct vnode *vp, off_t newsize, int trivial)
957 vm_pindex_t newpages, oldpages;
958 struct tmpfs_mount *tmp;
959 struct tmpfs_node *node;
963 KKASSERT(vp->v_type == VREG);
964 KKASSERT(newsize >= 0);
967 node = VP_TO_TMPFS_NODE(vp);
968 tmp = VFS_TO_TMPFS(vp->v_mount);
971 * Convert the old and new sizes to the number of pages needed to
972 * store them. It may happen that we do not need to do anything
973 * because the last allocated page can accommodate the change on
976 TMPFS_NODE_LOCK(node);
977 oldsize = node->tn_size;
978 oldpages = round_page64(oldsize) / PAGE_SIZE;
979 KKASSERT(oldpages == node->tn_reg.tn_aobj_pages);
980 newpages = round_page64(newsize) / PAGE_SIZE;
982 if (newpages > oldpages &&
983 tmp->tm_pages_used + newpages - oldpages > tmp->tm_pages_max) {
984 TMPFS_NODE_UNLOCK(node);
988 node->tn_reg.tn_aobj_pages = newpages;
989 node->tn_size = newsize;
990 TMPFS_NODE_UNLOCK(node);
993 tmp->tm_pages_used += (newpages - oldpages);
997 * When adjusting the vnode filesize and its VM object we must
998 * also adjust our backing VM object (aobj). The blocksize
999 * used must match the block sized we use for the buffer cache.
1001 * The backing VM object contains no VM pages, only swap
1004 if (newsize < oldsize) {
1009 error = nvtruncbuf(vp, newsize, TMPFS_BLKSIZE, -1, 0);
1010 aobj = node->tn_reg.tn_aobj;
1013 nsize = vp->v_object->size;
1014 if (nsize < osize) {
1016 swap_pager_freespace(aobj, nsize,
1023 error = nvextendbuf(vp, oldsize, newsize,
1024 TMPFS_BLKSIZE, TMPFS_BLKSIZE,
1026 aobj = node->tn_reg.tn_aobj;
1028 aobj->size = vp->v_object->size;
1035 /* --------------------------------------------------------------------- */
1038 * Change flags of the given vnode.
1039 * Caller should execute tmpfs_update on vp after a successful execution.
1040 * The vnode must be locked on entry and remain locked on exit.
1043 tmpfs_chflags(struct vnode *vp, int vaflags, struct ucred *cred)
1046 struct tmpfs_node *node;
1049 KKASSERT(vn_islocked(vp));
1051 node = VP_TO_TMPFS_NODE(vp);
1052 flags = node->tn_flags;
1054 /* Disallow this operation if the file system is mounted read-only. */
1055 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1057 error = vop_helper_setattr_flags(&flags, vaflags, node->tn_uid, cred);
1059 /* Actually change the flags on the node itself */
1061 TMPFS_NODE_LOCK(node);
1062 node->tn_flags = flags;
1063 node->tn_status |= TMPFS_NODE_CHANGED;
1064 TMPFS_NODE_UNLOCK(node);
1067 KKASSERT(vn_islocked(vp));
1072 /* --------------------------------------------------------------------- */
1075 * Change access mode on the given vnode.
1076 * Caller should execute tmpfs_update on vp after a successful execution.
1077 * The vnode must be locked on entry and remain locked on exit.
1080 tmpfs_chmod(struct vnode *vp, mode_t vamode, struct ucred *cred)
1082 struct tmpfs_node *node;
1086 KKASSERT(vn_islocked(vp));
1088 node = VP_TO_TMPFS_NODE(vp);
1090 /* Disallow this operation if the file system is mounted read-only. */
1091 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1094 /* Immutable or append-only files cannot be modified, either. */
1095 if (node->tn_flags & (IMMUTABLE | APPEND))
1098 cur_mode = node->tn_mode;
1099 error = vop_helper_chmod(vp, vamode, cred, node->tn_uid, node->tn_gid,
1103 (node->tn_mode & ALLPERMS) != (cur_mode & ALLPERMS)) {
1104 TMPFS_NODE_LOCK(node);
1105 node->tn_mode &= ~ALLPERMS;
1106 node->tn_mode |= cur_mode & ALLPERMS;
1108 node->tn_status |= TMPFS_NODE_CHANGED;
1109 TMPFS_NODE_UNLOCK(node);
1112 KKASSERT(vn_islocked(vp));
1117 /* --------------------------------------------------------------------- */
1120 * Change ownership of the given vnode. At least one of uid or gid must
1121 * be different than VNOVAL. If one is set to that value, the attribute
1123 * Caller should execute tmpfs_update on vp after a successful execution.
1124 * The vnode must be locked on entry and remain locked on exit.
1127 tmpfs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred)
1132 struct tmpfs_node *node;
1135 KKASSERT(vn_islocked(vp));
1136 node = VP_TO_TMPFS_NODE(vp);
1138 /* Disallow this operation if the file system is mounted read-only. */
1139 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1142 /* Immutable or append-only files cannot be modified, either. */
1143 if (node->tn_flags & (IMMUTABLE | APPEND))
1146 cur_uid = node->tn_uid;
1147 cur_gid = node->tn_gid;
1148 cur_mode = node->tn_mode;
1149 error = vop_helper_chown(vp, uid, gid, cred,
1150 &cur_uid, &cur_gid, &cur_mode);
1153 TMPFS_NODE_LOCK(node);
1154 if (cur_uid != node->tn_uid ||
1155 cur_gid != node->tn_gid ||
1156 cur_mode != node->tn_mode) {
1157 node->tn_uid = cur_uid;
1158 node->tn_gid = cur_gid;
1159 node->tn_mode = cur_mode;
1160 node->tn_status |= TMPFS_NODE_CHANGED;
1162 TMPFS_NODE_UNLOCK(node);
1168 /* --------------------------------------------------------------------- */
1171 * Change size of the given vnode.
1172 * Caller should execute tmpfs_update on vp after a successful execution.
1173 * The vnode must be locked on entry and remain locked on exit.
1176 tmpfs_chsize(struct vnode *vp, u_quad_t size, struct ucred *cred)
1179 struct tmpfs_node *node;
1181 KKASSERT(vn_islocked(vp));
1183 node = VP_TO_TMPFS_NODE(vp);
1185 /* Decide whether this is a valid operation based on the file type. */
1187 switch (vp->v_type) {
1192 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1201 /* Allow modifications of special files even if in the file
1202 * system is mounted read-only (we are not modifying the
1203 * files themselves, but the objects they represent). */
1207 /* Anything else is unsupported. */
1211 /* Immutable or append-only files cannot be modified, either. */
1212 if (node->tn_flags & (IMMUTABLE | APPEND))
1215 error = tmpfs_truncate(vp, size);
1216 /* tmpfs_truncate will raise the NOTE_EXTEND and NOTE_ATTRIB kevents
1217 * for us, as will update tn_status; no need to do that here. */
1219 KKASSERT(vn_islocked(vp));
1224 /* --------------------------------------------------------------------- */
1227 * Change access and modification times of the given vnode.
1228 * Caller should execute tmpfs_update on vp after a successful execution.
1229 * The vnode must be locked on entry and remain locked on exit.
1232 tmpfs_chtimes(struct vnode *vp, struct timespec *atime, struct timespec *mtime,
1233 int vaflags, struct ucred *cred)
1235 struct tmpfs_node *node;
1237 KKASSERT(vn_islocked(vp));
1239 node = VP_TO_TMPFS_NODE(vp);
1241 /* Disallow this operation if the file system is mounted read-only. */
1242 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1245 /* Immutable or append-only files cannot be modified, either. */
1246 if (node->tn_flags & (IMMUTABLE | APPEND))
1249 TMPFS_NODE_LOCK(node);
1250 if (atime->tv_sec != VNOVAL && atime->tv_nsec != VNOVAL)
1251 node->tn_status |= TMPFS_NODE_ACCESSED;
1253 if (mtime->tv_sec != VNOVAL && mtime->tv_nsec != VNOVAL)
1254 node->tn_status |= TMPFS_NODE_MODIFIED;
1256 TMPFS_NODE_UNLOCK(node);
1258 tmpfs_itimes(vp, atime, mtime);
1260 KKASSERT(vn_islocked(vp));
1265 /* --------------------------------------------------------------------- */
1266 /* Sync timestamps */
1268 tmpfs_itimes(struct vnode *vp, const struct timespec *acc,
1269 const struct timespec *mod)
1271 struct tmpfs_node *node;
1272 struct timespec now;
1274 node = VP_TO_TMPFS_NODE(vp);
1276 if ((node->tn_status & (TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED |
1277 TMPFS_NODE_CHANGED)) == 0)
1280 vfs_timestamp(&now);
1282 TMPFS_NODE_LOCK(node);
1283 if (node->tn_status & TMPFS_NODE_ACCESSED) {
1286 node->tn_atime = acc->tv_sec;
1287 node->tn_atimensec = acc->tv_nsec;
1289 if (node->tn_status & TMPFS_NODE_MODIFIED) {
1292 node->tn_mtime = mod->tv_sec;
1293 node->tn_mtimensec = mod->tv_nsec;
1295 if (node->tn_status & TMPFS_NODE_CHANGED) {
1296 node->tn_ctime = now.tv_sec;
1297 node->tn_ctimensec = now.tv_nsec;
1300 ~(TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | TMPFS_NODE_CHANGED);
1301 TMPFS_NODE_UNLOCK(node);
1304 /* --------------------------------------------------------------------- */
1307 tmpfs_update(struct vnode *vp)
1309 tmpfs_itimes(vp, NULL, NULL);
1312 /* --------------------------------------------------------------------- */
1315 tmpfs_truncate(struct vnode *vp, off_t length)
1318 struct tmpfs_node *node;
1320 node = VP_TO_TMPFS_NODE(vp);
1327 if (node->tn_size == length) {
1332 if (length > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
1336 error = tmpfs_reg_resize(vp, length, 1);
1339 TMPFS_NODE_LOCK(node);
1340 node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
1341 TMPFS_NODE_UNLOCK(node);
1350 /* --------------------------------------------------------------------- */
1353 tmpfs_fetch_ino(struct tmpfs_mount *tmp)
1358 ret = tmp->tm_ino++;
1365 tmpfs_dirtree_compare(struct tmpfs_dirent *a, struct tmpfs_dirent *b)
1367 if (a->td_namelen > b->td_namelen)
1369 else if (a->td_namelen < b->td_namelen)
1372 return strncmp(a->td_name, b->td_name, a->td_namelen);
1376 tmpfs_dirtree_compare_cookie(struct tmpfs_dirent *a, struct tmpfs_dirent *b)