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>
42 #include <sys/spinlock2.h>
44 #include <sys/systm.h>
45 #include <sys/vnode.h>
46 #include <sys/vmmeter.h>
49 #include <vm/vm_object.h>
50 #include <vm/vm_page.h>
51 #include <vm/vm_pager.h>
52 #include <vm/vm_extern.h>
54 #include <vfs/tmpfs/tmpfs.h>
55 #include <vfs/tmpfs/tmpfs_vnops.h>
57 static ino_t t_ino = 2;
58 static struct spinlock ino_lock;
59 static ino_t tmpfs_fetch_ino(void);
61 /* --------------------------------------------------------------------- */
64 * Allocates a new node of type 'type' inside the 'tmp' mount point, with
65 * its owner set to 'uid', its group to 'gid' and its mode set to 'mode',
66 * using the credentials of the process 'p'.
68 * If the node type is set to 'VDIR', then the parent parameter must point
69 * to the parent directory of the node being created. It may only be NULL
70 * while allocating the root node.
72 * If the node type is set to 'VBLK' or 'VCHR', then the rdev parameter
73 * specifies the device the node represents.
75 * If the node type is set to 'VLNK', then the parameter target specifies
76 * the file name of the target file for the symbolic link that is being
79 * Note that new nodes are retrieved from the available list if it has
80 * items or, if it is empty, from the node pool as long as there is enough
81 * space to create them.
83 * Returns zero on success or an appropriate error code on failure.
86 tmpfs_alloc_node(struct tmpfs_mount *tmp, enum vtype type,
87 uid_t uid, gid_t gid, mode_t mode, struct tmpfs_node *parent,
88 char *target, int rmajor, int rminor, struct tmpfs_node **node)
90 struct tmpfs_node *nnode;
94 /* If the root directory of the 'tmp' file system is not yet
95 * allocated, this must be the request to do it. */
96 KKASSERT(IMPLIES(tmp->tm_root == NULL, parent == NULL && type == VDIR));
98 KKASSERT(IFF(type == VLNK, target != NULL));
99 KKASSERT(IFF(type == VBLK || type == VCHR, rmajor != VNOVAL));
101 if (tmp->tm_nodes_inuse >= tmp->tm_nodes_max)
104 nnode = objcache_get(tmp->tm_node_pool, M_WAITOK | M_NULLOK);
108 /* Generic initialization. */
109 nnode->tn_type = type;
111 nnode->tn_ctime = nnode->tn_mtime = nnode->tn_atime
113 nnode->tn_ctimensec = nnode->tn_mtimensec = nnode->tn_atimensec
117 nnode->tn_mode = mode;
118 nnode->tn_id = tmpfs_fetch_ino();
119 nnode->tn_advlock.init_done = 0;
121 /* Type-specific initialization. */
122 switch (nnode->tn_type) {
125 rdev = makeudev(rmajor, rminor);
126 if (rdev == NOUDEV) {
127 objcache_put(tmp->tm_node_pool, nnode);
130 nnode->tn_rdev = rdev;
134 TAILQ_INIT(&nnode->tn_dir.tn_dirhead);
135 KKASSERT(parent != nnode);
136 KKASSERT(IMPLIES(parent == NULL, tmp->tm_root == NULL));
137 nnode->tn_dir.tn_parent = parent;
138 nnode->tn_dir.tn_readdir_lastn = 0;
139 nnode->tn_dir.tn_readdir_lastp = NULL;
143 TMPFS_NODE_LOCK(parent);
145 TMPFS_NODE_UNLOCK(parent);
155 nnode->tn_size = strlen(target);
156 nnode->tn_link = kmalloc(nnode->tn_size + 1, tmp->tm_name_zone,
157 M_WAITOK | M_NULLOK);
158 if (nnode->tn_link == NULL) {
159 objcache_put(tmp->tm_node_pool, nnode);
162 bcopy(target, nnode->tn_link, nnode->tn_size);
163 nnode->tn_link[nnode->tn_size] = '\0';
167 nnode->tn_reg.tn_aobj =
168 swap_pager_alloc(NULL, 0, VM_PROT_DEFAULT, 0);
169 nnode->tn_reg.tn_aobj_pages = 0;
174 panic("tmpfs_alloc_node: type %p %d", nnode, (int)nnode->tn_type);
177 TMPFS_NODE_LOCK(nnode);
179 LIST_INSERT_HEAD(&tmp->tm_nodes_used, nnode, tn_entries);
180 tmp->tm_nodes_inuse++;
182 TMPFS_NODE_UNLOCK(nnode);
188 /* --------------------------------------------------------------------- */
191 * Destroys the node pointed to by node from the file system 'tmp'.
192 * If the node does not belong to the given mount point, the results are
195 * If the node references a directory; no entries are allowed because
196 * their removal could need a recursive algorithm, something forbidden in
197 * kernel space. Furthermore, there is not need to provide such
198 * functionality (recursive removal) because the only primitives offered
199 * to the user are the removal of empty directories and the deletion of
202 * Note that nodes are not really deleted; in fact, when a node has been
203 * allocated, it cannot be deleted during the whole life of the file
204 * system. Instead, they are moved to the available list and remain there
208 tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
210 vm_pindex_t pages = 0;
213 TMPFS_ASSERT_ELOCKED(node);
214 KKASSERT(node->tn_vnode == NULL);
215 KKASSERT((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0);
219 LIST_REMOVE(node, tn_entries);
220 tmp->tm_nodes_inuse--;
222 TMPFS_NODE_UNLOCK(node);
224 switch (node->tn_type) {
226 /* Do not do anything. VNON is provided to let the
227 * allocation routine clean itself easily by avoiding
228 * duplicating code in it. */
237 * The parent link can be NULL if this is the root
242 KKASSERT(node->tn_dir.tn_parent || node == tmp->tm_root);
243 if (node->tn_dir.tn_parent) {
244 TMPFS_NODE_LOCK(node->tn_dir.tn_parent);
245 node->tn_dir.tn_parent->tn_links--;
248 * If the parent directory has no more links and
249 * no vnode ref nothing is going to come along
250 * and clean it up unless we do it here.
252 if (node->tn_dir.tn_parent->tn_links == 0 &&
253 node->tn_dir.tn_parent->tn_vnode == NULL) {
254 tmpfs_free_node(tmp, node->tn_dir.tn_parent);
255 /* eats parent lock */
257 TMPFS_NODE_UNLOCK(node->tn_dir.tn_parent);
259 node->tn_dir.tn_parent = NULL;
263 * If the root node is being destroyed don't leave a
264 * dangling pointer in tmpfs_mount.
266 if (node == tmp->tm_root)
275 kfree(node->tn_link, tmp->tm_name_zone);
276 node->tn_link = NULL;
281 if (node->tn_reg.tn_aobj != NULL)
282 vm_object_deallocate(node->tn_reg.tn_aobj);
283 node->tn_reg.tn_aobj = NULL;
284 pages = node->tn_reg.tn_aobj_pages;
288 panic("tmpfs_free_node: type %p %d", node, (int)node->tn_type);
292 * Clean up fields for the next allocation. The objcache only ctors
295 tmpfs_node_ctor(node, NULL, 0);
296 objcache_put(tmp->tm_node_pool, node);
297 /* node is now invalid */
300 tmp->tm_pages_used -= pages;
304 /* --------------------------------------------------------------------- */
307 * Allocates a new directory entry for the node node with a name of name.
308 * The new directory entry is returned in *de.
310 * The link count of node is increased by one to reflect the new object
313 * Returns zero on success or an appropriate error code on failure.
316 tmpfs_alloc_dirent(struct tmpfs_mount *tmp, struct tmpfs_node *node,
317 const char *name, uint16_t len, struct tmpfs_dirent **de)
319 struct tmpfs_dirent *nde;
321 nde = objcache_get(tmp->tm_dirent_pool, M_WAITOK);
322 nde->td_name = kmalloc(len + 1, tmp->tm_name_zone, M_WAITOK | M_NULLOK);
323 if (nde->td_name == NULL) {
324 objcache_put(tmp->tm_dirent_pool, nde);
328 nde->td_namelen = len;
329 bcopy(name, nde->td_name, len);
330 nde->td_name[len] = '\0';
334 TMPFS_NODE_LOCK(node);
336 TMPFS_NODE_UNLOCK(node);
343 /* --------------------------------------------------------------------- */
346 * Frees a directory entry. It is the caller's responsibility to destroy
347 * the node referenced by it if needed.
349 * The link count of node is decreased by one to reflect the removal of an
350 * object that referenced it. This only happens if 'node_exists' is true;
351 * otherwise the function will not access the node referred to by the
352 * directory entry, as it may already have been released from the outside.
355 tmpfs_free_dirent(struct tmpfs_mount *tmp, struct tmpfs_dirent *de)
357 struct tmpfs_node *node;
361 TMPFS_NODE_LOCK(node);
362 TMPFS_ASSERT_ELOCKED(node);
363 KKASSERT(node->tn_links > 0);
365 TMPFS_NODE_UNLOCK(node);
367 kfree(de->td_name, tmp->tm_name_zone);
371 objcache_put(tmp->tm_dirent_pool, de);
374 /* --------------------------------------------------------------------- */
377 * Allocates a new vnode for the node node or returns a new reference to
378 * an existing one if the node had already a vnode referencing it. The
379 * resulting locked vnode is returned in *vpp.
381 * Returns zero on success or an appropriate error code on failure.
384 tmpfs_alloc_vp(struct mount *mp, struct tmpfs_node *node, int lkflag,
392 * Interlocked extraction from node. This can race many things.
393 * We have to get a soft reference on the vnode while we hold
394 * the node locked, then acquire it properly and check for races.
396 TMPFS_NODE_LOCK(node);
397 if ((vp = node->tn_vnode) != NULL) {
398 KKASSERT((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0);
399 vhold_interlocked(vp);
400 TMPFS_NODE_UNLOCK(node);
402 if (vget(vp, lkflag | LK_EXCLUSIVE) != 0) {
406 if (node->tn_vnode != vp) {
417 * This should never happen.
419 if (node->tn_vpstate & TMPFS_VNODE_DOOMED) {
420 TMPFS_NODE_UNLOCK(node);
426 * Interlock against other calls to tmpfs_alloc_vp() trying to
427 * allocate and assign a vp to node.
429 if (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) {
430 node->tn_vpstate |= TMPFS_VNODE_WANT;
431 error = tsleep(&node->tn_vpstate, PINTERLOCKED | PCATCH,
432 "tmpfs_alloc_vp", 0);
433 TMPFS_NODE_UNLOCK(node);
438 node->tn_vpstate |= TMPFS_VNODE_ALLOCATING;
439 TMPFS_NODE_UNLOCK(node);
442 * Allocate a new vnode (may block). The ALLOCATING flag should
443 * prevent a race against someone else assigning node->tn_vnode.
445 error = getnewvnode(VT_TMPFS, mp, &vp, VLKTIMEOUT, LK_CANRECURSE);
449 KKASSERT(node->tn_vnode == NULL);
450 KKASSERT(vp != NULL);
452 vp->v_type = node->tn_type;
454 /* Type-specific initialization. */
455 switch (node->tn_type) {
463 vinitvmio(vp, node->tn_size, BMASK, -1);
468 vp->v_ops = &mp->mnt_vn_fifo_ops;
474 panic("tmpfs_alloc_vp: type %p %d", node, (int)node->tn_type);
480 TMPFS_NODE_LOCK(node);
482 KKASSERT(node->tn_vpstate & TMPFS_VNODE_ALLOCATING);
483 node->tn_vpstate &= ~TMPFS_VNODE_ALLOCATING;
486 if (node->tn_vpstate & TMPFS_VNODE_WANT) {
487 node->tn_vpstate &= ~TMPFS_VNODE_WANT;
488 TMPFS_NODE_UNLOCK(node);
489 wakeup(&node->tn_vpstate);
491 TMPFS_NODE_UNLOCK(node);
497 KKASSERT(IFF(error == 0, *vpp != NULL && vn_islocked(*vpp)));
499 TMPFS_NODE_LOCK(node);
500 KKASSERT(*vpp == node->tn_vnode);
501 TMPFS_NODE_UNLOCK(node);
507 /* --------------------------------------------------------------------- */
510 * Destroys the association between the vnode vp and the node it
514 tmpfs_free_vp(struct vnode *vp)
516 struct tmpfs_node *node;
518 node = VP_TO_TMPFS_NODE(vp);
520 TMPFS_NODE_LOCK(node);
521 KKASSERT(lockcount(TMPFS_NODE_MTX(node)) > 0);
522 node->tn_vnode = NULL;
523 TMPFS_NODE_UNLOCK(node);
527 /* --------------------------------------------------------------------- */
530 * Allocates a new file of type 'type' and adds it to the parent directory
531 * 'dvp'; this addition is done using the component name given in 'cnp'.
532 * The ownership of the new file is automatically assigned based on the
533 * credentials of the caller (through 'cnp'), the group is set based on
534 * the parent directory and the mode is determined from the 'vap' argument.
535 * If successful, *vpp holds a vnode to the newly created file and zero
536 * is returned. Otherwise *vpp is NULL and the function returns an
537 * appropriate error code.
540 tmpfs_alloc_file(struct vnode *dvp, struct vnode **vpp, struct vattr *vap,
541 struct namecache *ncp, struct ucred *cred, char *target)
544 struct tmpfs_dirent *de;
545 struct tmpfs_mount *tmp;
546 struct tmpfs_node *dnode;
547 struct tmpfs_node *node;
548 struct tmpfs_node *parent;
550 tmp = VFS_TO_TMPFS(dvp->v_mount);
551 dnode = VP_TO_TMPFS_DIR(dvp);
554 /* If the entry we are creating is a directory, we cannot overflow
555 * the number of links of its parent, because it will get a new
557 if (vap->va_type == VDIR) {
558 /* Ensure that we do not overflow the maximum number of links
559 * imposed by the system. */
560 KKASSERT(dnode->tn_links <= LINK_MAX);
561 if (dnode->tn_links == LINK_MAX) {
566 KKASSERT(parent != NULL);
570 /* Allocate a node that represents the new file. */
571 error = tmpfs_alloc_node(tmp, vap->va_type, cred->cr_uid,
572 dnode->tn_gid, vap->va_mode, parent, target, vap->va_rmajor, vap->va_rminor, &node);
575 TMPFS_NODE_LOCK(node);
577 /* Allocate a directory entry that points to the new file. */
578 error = tmpfs_alloc_dirent(tmp, node, ncp->nc_name, ncp->nc_nlen, &de);
580 tmpfs_free_node(tmp, node);
585 /* Allocate a vnode for the new file. */
586 error = tmpfs_alloc_vp(dvp->v_mount, node, LK_EXCLUSIVE, vpp);
588 tmpfs_free_dirent(tmp, de);
589 tmpfs_free_node(tmp, node);
594 /* Now that all required items are allocated, we can proceed to
595 * insert the new node into the directory, an operation that
597 tmpfs_dir_attach(dnode, de);
598 TMPFS_NODE_UNLOCK(node);
603 /* --------------------------------------------------------------------- */
606 * Attaches the directory entry de to the directory represented by vp.
607 * Note that this does not change the link count of the node pointed by
608 * the directory entry, as this is done by tmpfs_alloc_dirent.
611 tmpfs_dir_attach(struct tmpfs_node *dnode, struct tmpfs_dirent *de)
613 TMPFS_NODE_LOCK(dnode);
614 TAILQ_INSERT_TAIL(&dnode->tn_dir.tn_dirhead, de, td_entries);
616 TMPFS_ASSERT_ELOCKED(dnode);
617 dnode->tn_size += sizeof(struct tmpfs_dirent);
618 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
620 TMPFS_NODE_UNLOCK(dnode);
623 /* --------------------------------------------------------------------- */
626 * Detaches the directory entry de from the directory represented by vp.
627 * Note that this does not change the link count of the node pointed by
628 * the directory entry, as this is done by tmpfs_free_dirent.
631 tmpfs_dir_detach(struct tmpfs_node *dnode, struct tmpfs_dirent *de)
633 TMPFS_NODE_LOCK(dnode);
634 if (dnode->tn_dir.tn_readdir_lastp == de) {
635 dnode->tn_dir.tn_readdir_lastn = 0;
636 dnode->tn_dir.tn_readdir_lastp = NULL;
638 TAILQ_REMOVE(&dnode->tn_dir.tn_dirhead, de, td_entries);
640 TMPFS_ASSERT_ELOCKED(dnode);
641 dnode->tn_size -= sizeof(struct tmpfs_dirent);
642 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
644 TMPFS_NODE_UNLOCK(dnode);
647 /* --------------------------------------------------------------------- */
650 * Looks for a directory entry in the directory represented by node.
651 * 'ncp' describes the name of the entry to look for. Note that the .
652 * and .. components are not allowed as they do not physically exist
653 * within directories.
655 * Returns a pointer to the entry when found, otherwise NULL.
657 struct tmpfs_dirent *
658 tmpfs_dir_lookup(struct tmpfs_node *node, struct tmpfs_node *f,
659 struct namecache *ncp)
661 struct tmpfs_dirent *de;
662 int len = ncp->nc_nlen;
664 TMPFS_VALIDATE_DIR(node);
666 TAILQ_FOREACH(de, &node->tn_dir.tn_dirhead, td_entries) {
667 if (f != NULL && de->td_node != f)
669 if (len == de->td_namelen) {
670 if (!memcmp(ncp->nc_name, de->td_name, len))
675 TMPFS_NODE_LOCK(node);
676 node->tn_status |= TMPFS_NODE_ACCESSED;
677 TMPFS_NODE_UNLOCK(node);
682 /* --------------------------------------------------------------------- */
685 * Helper function for tmpfs_readdir. Creates a '.' entry for the given
686 * directory and returns it in the uio space. The function returns 0
687 * on success, -1 if there was not enough space in the uio structure to
688 * hold the directory entry or an appropriate error code if another
692 tmpfs_dir_getdotdent(struct tmpfs_node *node, struct uio *uio)
698 TMPFS_VALIDATE_DIR(node);
699 KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOT);
701 dent.d_ino = node->tn_id;
702 dent.d_type = DT_DIR;
704 dent.d_name[0] = '.';
705 dent.d_name[1] = '\0';
706 dirsize = _DIRENT_DIRSIZ(&dent);
708 if (dirsize > uio->uio_resid)
711 error = uiomove((caddr_t)&dent, dirsize, uio);
713 uio->uio_offset = TMPFS_DIRCOOKIE_DOTDOT;
716 TMPFS_NODE_LOCK(node);
717 node->tn_status |= TMPFS_NODE_ACCESSED;
718 TMPFS_NODE_UNLOCK(node);
723 /* --------------------------------------------------------------------- */
726 * Helper function for tmpfs_readdir. Creates a '..' entry for the given
727 * directory and returns it in the uio space. The function returns 0
728 * on success, -1 if there was not enough space in the uio structure to
729 * hold the directory entry or an appropriate error code if another
733 tmpfs_dir_getdotdotdent(struct tmpfs_mount *tmp, struct tmpfs_node *node,
740 TMPFS_VALIDATE_DIR(node);
741 KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOTDOT);
743 if (node->tn_dir.tn_parent) {
744 TMPFS_NODE_LOCK(node->tn_dir.tn_parent);
745 dent.d_ino = node->tn_dir.tn_parent->tn_id;
746 TMPFS_NODE_UNLOCK(node->tn_dir.tn_parent);
748 dent.d_ino = tmp->tm_root->tn_id;
751 dent.d_type = DT_DIR;
753 dent.d_name[0] = '.';
754 dent.d_name[1] = '.';
755 dent.d_name[2] = '\0';
756 dirsize = _DIRENT_DIRSIZ(&dent);
758 if (dirsize > uio->uio_resid)
761 error = uiomove((caddr_t)&dent, dirsize, uio);
763 struct tmpfs_dirent *de;
765 de = TAILQ_FIRST(&node->tn_dir.tn_dirhead);
767 uio->uio_offset = TMPFS_DIRCOOKIE_EOF;
769 uio->uio_offset = tmpfs_dircookie(de);
773 TMPFS_NODE_LOCK(node);
774 node->tn_status |= TMPFS_NODE_ACCESSED;
775 TMPFS_NODE_UNLOCK(node);
780 /* --------------------------------------------------------------------- */
783 * Lookup a directory entry by its associated cookie.
785 struct tmpfs_dirent *
786 tmpfs_dir_lookupbycookie(struct tmpfs_node *node, off_t cookie)
788 struct tmpfs_dirent *de;
790 if (cookie == node->tn_dir.tn_readdir_lastn &&
791 node->tn_dir.tn_readdir_lastp != NULL) {
792 return node->tn_dir.tn_readdir_lastp;
795 TAILQ_FOREACH(de, &node->tn_dir.tn_dirhead, td_entries) {
796 if (tmpfs_dircookie(de) == cookie) {
804 /* --------------------------------------------------------------------- */
807 * Helper function for tmpfs_readdir. Returns as much directory entries
808 * as can fit in the uio space. The read starts at uio->uio_offset.
809 * The function returns 0 on success, -1 if there was not enough space
810 * in the uio structure to hold the directory entry or an appropriate
811 * error code if another error happens.
814 tmpfs_dir_getdents(struct tmpfs_node *node, struct uio *uio, off_t *cntp)
818 struct tmpfs_dirent *de;
820 TMPFS_VALIDATE_DIR(node);
822 /* Locate the first directory entry we have to return. We have cached
823 * the last readdir in the node, so use those values if appropriate.
824 * Otherwise do a linear scan to find the requested entry. */
825 startcookie = uio->uio_offset;
826 KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOT);
827 KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOTDOT);
828 if (startcookie == TMPFS_DIRCOOKIE_EOF) {
831 de = tmpfs_dir_lookupbycookie(node, startcookie);
837 /* Read as much entries as possible; i.e., until we reach the end of
838 * the directory or we exhaust uio space. */
843 /* Create a dirent structure representing the current
844 * tmpfs_node and fill it. */
845 d.d_ino = de->td_node->tn_id;
846 switch (de->td_node->tn_type) {
876 panic("tmpfs_dir_getdents: type %p %d",
877 de->td_node, (int)de->td_node->tn_type);
879 d.d_namlen = de->td_namelen;
880 KKASSERT(de->td_namelen < sizeof(d.d_name));
881 bcopy(de->td_name, d.d_name, d.d_namlen);
882 d.d_name[d.d_namlen] = '\0';
883 reclen = _DIRENT_RECLEN(d.d_namlen);
885 /* Stop reading if the directory entry we are treating is
886 * bigger than the amount of data that can be returned. */
887 if (reclen > uio->uio_resid) {
892 /* Copy the new dirent structure into the output buffer and
893 * advance pointers. */
894 error = uiomove((caddr_t)&d, reclen, uio);
897 de = TAILQ_NEXT(de, td_entries);
898 } while (error == 0 && uio->uio_resid > 0 && de != NULL);
900 /* Update the offset and cache. */
902 uio->uio_offset = TMPFS_DIRCOOKIE_EOF;
903 node->tn_dir.tn_readdir_lastn = 0;
904 node->tn_dir.tn_readdir_lastp = NULL;
906 node->tn_dir.tn_readdir_lastn = uio->uio_offset = tmpfs_dircookie(de);
907 node->tn_dir.tn_readdir_lastp = de;
909 node->tn_status |= TMPFS_NODE_ACCESSED;
914 /* --------------------------------------------------------------------- */
917 * Resizes the aobj associated to the regular file pointed to by vp to
918 * the size newsize. 'vp' must point to a vnode that represents a regular
919 * file. 'newsize' must be positive.
921 * pass trivial as 1 when buf content will be overwritten, otherwise set 0
924 * Returns zero on success or an appropriate error code on failure.
927 tmpfs_reg_resize(struct vnode *vp, off_t newsize, int trivial)
930 vm_pindex_t newpages, oldpages;
931 struct tmpfs_mount *tmp;
932 struct tmpfs_node *node;
936 KKASSERT(vp->v_type == VREG);
937 KKASSERT(newsize >= 0);
940 node = VP_TO_TMPFS_NODE(vp);
941 tmp = VFS_TO_TMPFS(vp->v_mount);
943 /* Convert the old and new sizes to the number of pages needed to
944 * store them. It may happen that we do not need to do anything
945 * because the last allocated page can accommodate the change on
947 oldsize = node->tn_size;
948 oldpages = round_page64(oldsize) / PAGE_SIZE;
949 KKASSERT(oldpages == node->tn_reg.tn_aobj_pages);
950 newpages = round_page64(newsize) / PAGE_SIZE;
952 if (newpages > oldpages &&
953 tmp->tm_pages_used + newpages - oldpages > tmp->tm_pages_max) {
959 tmp->tm_pages_used += (newpages - oldpages);
962 TMPFS_NODE_LOCK(node);
963 node->tn_reg.tn_aobj_pages = newpages;
964 node->tn_size = newsize;
965 TMPFS_NODE_UNLOCK(node);
968 * When adjusting the vnode filesize and its VM object we must
969 * also adjust our backing VM object (aobj). The blocksize
970 * used must match the block sized we use for the buffer cache.
972 * The backing VM object contains no VM pages, only swap
975 if (newsize < oldsize) {
980 error = nvtruncbuf(vp, newsize, BSIZE, -1, 0);
981 aobj = node->tn_reg.tn_aobj;
984 nsize = vp->v_object->size;
987 swap_pager_freespace(aobj, nsize,
994 error = nvextendbuf(vp, oldsize, newsize, BSIZE, BSIZE,
996 aobj = node->tn_reg.tn_aobj;
998 aobj->size = vp->v_object->size;
1005 /* --------------------------------------------------------------------- */
1008 * Change flags of the given vnode.
1009 * Caller should execute tmpfs_update on vp after a successful execution.
1010 * The vnode must be locked on entry and remain locked on exit.
1013 tmpfs_chflags(struct vnode *vp, int vaflags, struct ucred *cred)
1016 struct tmpfs_node *node;
1019 KKASSERT(vn_islocked(vp));
1021 node = VP_TO_TMPFS_NODE(vp);
1022 flags = node->tn_flags;
1024 /* Disallow this operation if the file system is mounted read-only. */
1025 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1027 error = vop_helper_setattr_flags(&flags, vaflags, node->tn_uid, cred);
1030 * Unprivileged processes are not permitted to unset system
1031 * flags, or modify flags if any system flags are set.
1033 * Silently enforce SF_NOCACHE on the root tmpfs vnode so
1034 * tmpfs data is not double-cached by swapcache.
1037 TMPFS_NODE_LOCK(node);
1038 if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) {
1039 if (vp->v_flag & VROOT)
1040 flags |= SF_NOCACHE;
1041 node->tn_flags = flags;
1043 if (node->tn_flags & (SF_NOUNLINK | SF_IMMUTABLE |
1045 (flags & UF_SETTABLE) != flags) {
1048 node->tn_flags &= SF_SETTABLE;
1049 node->tn_flags |= (flags & UF_SETTABLE);
1052 node->tn_status |= TMPFS_NODE_CHANGED;
1053 TMPFS_NODE_UNLOCK(node);
1056 KKASSERT(vn_islocked(vp));
1061 /* --------------------------------------------------------------------- */
1064 * Change access mode on the given vnode.
1065 * Caller should execute tmpfs_update on vp after a successful execution.
1066 * The vnode must be locked on entry and remain locked on exit.
1069 tmpfs_chmod(struct vnode *vp, mode_t vamode, struct ucred *cred)
1071 struct tmpfs_node *node;
1075 KKASSERT(vn_islocked(vp));
1077 node = VP_TO_TMPFS_NODE(vp);
1079 /* Disallow this operation if the file system is mounted read-only. */
1080 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1083 /* Immutable or append-only files cannot be modified, either. */
1084 if (node->tn_flags & (IMMUTABLE | APPEND))
1087 cur_mode = node->tn_mode;
1088 error = vop_helper_chmod(vp, vamode, cred, node->tn_uid, node->tn_gid,
1092 (node->tn_mode & ALLPERMS) != (cur_mode & ALLPERMS)) {
1093 TMPFS_NODE_LOCK(node);
1094 node->tn_mode &= ~ALLPERMS;
1095 node->tn_mode |= cur_mode & ALLPERMS;
1097 node->tn_status |= TMPFS_NODE_CHANGED;
1098 TMPFS_NODE_UNLOCK(node);
1101 KKASSERT(vn_islocked(vp));
1106 /* --------------------------------------------------------------------- */
1109 * Change ownership of the given vnode. At least one of uid or gid must
1110 * be different than VNOVAL. If one is set to that value, the attribute
1112 * Caller should execute tmpfs_update on vp after a successful execution.
1113 * The vnode must be locked on entry and remain locked on exit.
1116 tmpfs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred)
1121 struct tmpfs_node *node;
1124 KKASSERT(vn_islocked(vp));
1125 node = VP_TO_TMPFS_NODE(vp);
1127 /* Disallow this operation if the file system is mounted read-only. */
1128 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1131 /* Immutable or append-only files cannot be modified, either. */
1132 if (node->tn_flags & (IMMUTABLE | APPEND))
1135 cur_uid = node->tn_uid;
1136 cur_gid = node->tn_gid;
1137 cur_mode = node->tn_mode;
1138 error = vop_helper_chown(vp, uid, gid, cred,
1139 &cur_uid, &cur_gid, &cur_mode);
1142 TMPFS_NODE_LOCK(node);
1143 if (cur_uid != node->tn_uid ||
1144 cur_gid != node->tn_gid ||
1145 cur_mode != node->tn_mode) {
1146 node->tn_uid = cur_uid;
1147 node->tn_gid = cur_gid;
1148 node->tn_mode = cur_mode;
1149 node->tn_status |= TMPFS_NODE_CHANGED;
1151 TMPFS_NODE_UNLOCK(node);
1157 /* --------------------------------------------------------------------- */
1160 * Change size of the given vnode.
1161 * Caller should execute tmpfs_update on vp after a successful execution.
1162 * The vnode must be locked on entry and remain locked on exit.
1165 tmpfs_chsize(struct vnode *vp, u_quad_t size, struct ucred *cred)
1168 struct tmpfs_node *node;
1170 KKASSERT(vn_islocked(vp));
1172 node = VP_TO_TMPFS_NODE(vp);
1174 /* Decide whether this is a valid operation based on the file type. */
1176 switch (vp->v_type) {
1181 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1190 /* Allow modifications of special files even if in the file
1191 * system is mounted read-only (we are not modifying the
1192 * files themselves, but the objects they represent). */
1196 /* Anything else is unsupported. */
1200 /* Immutable or append-only files cannot be modified, either. */
1201 if (node->tn_flags & (IMMUTABLE | APPEND))
1204 error = tmpfs_truncate(vp, size);
1205 /* tmpfs_truncate will raise the NOTE_EXTEND and NOTE_ATTRIB kevents
1206 * for us, as will update tn_status; no need to do that here. */
1208 KKASSERT(vn_islocked(vp));
1213 /* --------------------------------------------------------------------- */
1216 * Change access and modification times of the given vnode.
1217 * Caller should execute tmpfs_update on vp after a successful execution.
1218 * The vnode must be locked on entry and remain locked on exit.
1221 tmpfs_chtimes(struct vnode *vp, struct timespec *atime, struct timespec *mtime,
1222 int vaflags, struct ucred *cred)
1224 struct tmpfs_node *node;
1226 KKASSERT(vn_islocked(vp));
1228 node = VP_TO_TMPFS_NODE(vp);
1230 /* Disallow this operation if the file system is mounted read-only. */
1231 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1234 /* Immutable or append-only files cannot be modified, either. */
1235 if (node->tn_flags & (IMMUTABLE | APPEND))
1238 TMPFS_NODE_LOCK(node);
1239 if (atime->tv_sec != VNOVAL && atime->tv_nsec != VNOVAL)
1240 node->tn_status |= TMPFS_NODE_ACCESSED;
1242 if (mtime->tv_sec != VNOVAL && mtime->tv_nsec != VNOVAL)
1243 node->tn_status |= TMPFS_NODE_MODIFIED;
1245 TMPFS_NODE_UNLOCK(node);
1247 tmpfs_itimes(vp, atime, mtime);
1249 KKASSERT(vn_islocked(vp));
1254 /* --------------------------------------------------------------------- */
1255 /* Sync timestamps */
1257 tmpfs_itimes(struct vnode *vp, const struct timespec *acc,
1258 const struct timespec *mod)
1260 struct tmpfs_node *node;
1261 struct timespec now;
1263 node = VP_TO_TMPFS_NODE(vp);
1265 if ((node->tn_status & (TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED |
1266 TMPFS_NODE_CHANGED)) == 0)
1269 vfs_timestamp(&now);
1271 TMPFS_NODE_LOCK(node);
1272 if (node->tn_status & TMPFS_NODE_ACCESSED) {
1275 node->tn_atime = acc->tv_sec;
1276 node->tn_atimensec = acc->tv_nsec;
1278 if (node->tn_status & TMPFS_NODE_MODIFIED) {
1281 node->tn_mtime = mod->tv_sec;
1282 node->tn_mtimensec = mod->tv_nsec;
1284 if (node->tn_status & TMPFS_NODE_CHANGED) {
1285 node->tn_ctime = now.tv_sec;
1286 node->tn_ctimensec = now.tv_nsec;
1289 ~(TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | TMPFS_NODE_CHANGED);
1290 TMPFS_NODE_UNLOCK(node);
1293 /* --------------------------------------------------------------------- */
1296 tmpfs_update(struct vnode *vp)
1299 tmpfs_itimes(vp, NULL, NULL);
1302 /* --------------------------------------------------------------------- */
1305 tmpfs_truncate(struct vnode *vp, off_t length)
1308 struct tmpfs_node *node;
1310 node = VP_TO_TMPFS_NODE(vp);
1317 if (node->tn_size == length) {
1322 if (length > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
1326 error = tmpfs_reg_resize(vp, length, 1);
1329 TMPFS_NODE_LOCK(node);
1330 node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
1331 TMPFS_NODE_UNLOCK(node);
1340 /* --------------------------------------------------------------------- */
1343 tmpfs_fetch_ino(void)
1347 spin_lock(&ino_lock);
1349 spin_unlock(&ino_lock);