/*
- * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2002-2012 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
- *
- * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* Please see the License for the specific language governing rights and
* limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/vnode.h>
+#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/queue.h>
+
+#include "hfs.h" /* XXX bringup */
#include "hfs_cnode.h"
+extern lck_attr_t * hfs_lock_attr;
+extern lck_grp_t * hfs_mutex_group;
+extern lck_grp_t * hfs_rwlock_group;
+
+lck_grp_t * chash_lck_grp;
+lck_grp_attr_t * chash_lck_grp_attr;
+lck_attr_t * chash_lck_attr;
+
+
+#define CNODEHASH(hfsmp, inum) (&hfsmp->hfs_cnodehashtbl[(inum) & hfsmp->hfs_cnodehash])
-/*
- * Structures associated with cnode caching.
- */
-LIST_HEAD(cnodehashhead, cnode) *cnodehashtbl;
-u_long cnodehash; /* size of hash table - 1 */
-#define CNODEHASH(device, inum) (&cnodehashtbl[((device) + (inum)) & cnodehash])
-struct slock hfs_chash_slock;
/*
* Initialize cnode hash table.
void
hfs_chashinit()
{
- cnodehashtbl = hashinit(desiredvnodes, M_HFSMNT, &cnodehash);
- simple_lock_init(&hfs_chash_slock);
+ chash_lck_grp_attr= lck_grp_attr_alloc_init();
+ chash_lck_grp = lck_grp_alloc_init("cnode_hash", chash_lck_grp_attr);
+ chash_lck_attr = lck_attr_alloc_init();
+}
+
+static void hfs_chash_lock(struct hfsmount *hfsmp)
+{
+ lck_mtx_lock(&hfsmp->hfs_chash_mutex);
+}
+
+static void hfs_chash_lock_spin(struct hfsmount *hfsmp)
+{
+ lck_mtx_lock_spin(&hfsmp->hfs_chash_mutex);
+}
+
+static void hfs_chash_lock_convert (__unused struct hfsmount *hfsmp)
+{
+ lck_mtx_convert_spin(&hfsmp->hfs_chash_mutex);
+}
+
+static void hfs_chash_unlock(struct hfsmount *hfsmp)
+{
+ lck_mtx_unlock(&hfsmp->hfs_chash_mutex);
+}
+
+__private_extern__
+void
+hfs_chashinit_finish(struct hfsmount *hfsmp)
+{
+ lck_mtx_init(&hfsmp->hfs_chash_mutex, chash_lck_grp, chash_lck_attr);
+
+ hfsmp->hfs_cnodehashtbl = hashinit(desiredvnodes / 4, M_HFSMNT, &hfsmp->hfs_cnodehash);
+}
+
+__private_extern__
+void
+hfs_delete_chash(struct hfsmount *hfsmp)
+{
+ lck_mtx_destroy(&hfsmp->hfs_chash_mutex, chash_lck_grp);
+
+ FREE(hfsmp->hfs_cnodehashtbl, M_HFSMNT);
}
* Use the device, inum pair to find the incore cnode.
*
* If it is in core, but locked, wait for it.
- *
- * If the requested vnode (fork) is not available, then
- * take a reference on the other vnode (fork) so that
- * the upcoming getnewvnode can not aquire it.
*/
-__private_extern__
-struct cnode *
-hfs_chashget(dev_t dev, ino_t inum, int wantrsrc,
- struct vnode **vpp, struct vnode **rvpp)
+struct vnode *
+hfs_chash_getvnode(struct hfsmount *hfsmp, ino_t inum, int wantrsrc, int skiplock, int allow_deleted)
{
- struct proc *p = current_proc();
struct cnode *cp;
struct vnode *vp;
int error;
+ u_int32_t vid;
- *vpp = NULLVP;
- *rvpp = NULLVP;
/*
* Go through the hash list
* If a cnode is in the process of being cleaned out or being
* allocated, wait for it to be finished and then try again.
*/
loop:
- simple_lock(&hfs_chash_slock);
- for (cp = CNODEHASH(dev, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
- if ((cp->c_fileid != inum) || (cp->c_dev != dev))
+ hfs_chash_lock_spin(hfsmp);
+
+ for (cp = CNODEHASH(hfsmp, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
+ if (cp->c_fileid != inum)
continue;
- if (ISSET(cp->c_flag, C_ALLOC)) {
- /*
- * cnode is being created. Wait for it to finish.
- */
- SET(cp->c_flag, C_WALLOC);
- simple_unlock(&hfs_chash_slock);
- (void) tsleep((caddr_t)cp, PINOD, "hfs_chashget-1", 0);
+ /* Wait if cnode is being created or reclaimed. */
+ if (ISSET(cp->c_hflag, H_ALLOC | H_TRANSIT | H_ATTACH)) {
+ SET(cp->c_hflag, H_WAITING);
+
+ (void) msleep(cp, &hfsmp->hfs_chash_mutex, PDROP | PINOD,
+ "hfs_chash_getvnode", 0);
goto loop;
- }
- if (ISSET(cp->c_flag, C_TRANSIT)) {
- /*
- * cnode is getting reclaimed wait for
- * the operation to complete and return
- * error
+ }
+ /* Obtain the desired vnode. */
+ vp = wantrsrc ? cp->c_rsrc_vp : cp->c_vp;
+ if (vp == NULLVP)
+ goto exit;
+
+ vid = vnode_vid(vp);
+ hfs_chash_unlock(hfsmp);
+
+ if ((error = vnode_getwithvid(vp, vid))) {
+ /*
+ * If vnode is being reclaimed, or has
+ * already changed identity, no need to wait
*/
- SET(cp->c_flag, C_WTRANSIT);
- simple_unlock(&hfs_chash_slock);
- (void)tsleep((caddr_t)cp, PINOD, "hfs_chashget-2", 0);
- goto loop;
+ return (NULL);
+ }
+ if (!skiplock && hfs_lock(cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_DEFAULT) != 0) {
+ vnode_put(vp);
+ return (NULL);
+ }
+
+ /*
+ * Skip cnodes that are not in the name space anymore
+ * we need to check with the cnode lock held because
+ * we may have blocked acquiring the vnode ref or the
+ * lock on the cnode which would allow the node to be
+ * unlinked
+ */
+ if (!allow_deleted) {
+ if (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
+ if (!skiplock) {
+ hfs_unlock(cp);
+ }
+ vnode_put(vp);
+ return (NULL);
+ }
}
- if (cp->c_flag & (C_NOEXISTS | C_DELETED))
+ return (vp);
+ }
+exit:
+ hfs_chash_unlock(hfsmp);
+ return (NULL);
+}
+
+
+/*
+ * Use the device, fileid pair to snoop an incore cnode.
+ *
+ * A cnode can exists in chash even after it has been
+ * deleted from the catalog, so this function returns
+ * ENOENT if C_NOEXIST is set in the cnode's flag.
+ *
+ */
+int
+hfs_chash_snoop(struct hfsmount *hfsmp, ino_t inum, int existence_only, int (*callout)(const struct cat_desc *,
+ const struct cat_attr *, void *), void * arg)
+{
+ struct cnode *cp;
+ int result = ENOENT;
+
+ /*
+ * Go through the hash list
+ * If a cnode is in the process of being cleaned out or being
+ * allocated, wait for it to be finished and then try again.
+ */
+ hfs_chash_lock(hfsmp);
+
+ for (cp = CNODEHASH(hfsmp, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
+ if (cp->c_fileid != inum)
continue;
+
+ /*
+ * Under normal circumstances, we would want to return ENOENT if a cnode is in
+ * the hash and it is marked C_NOEXISTS or C_DELETED. However, if the CNID
+ * namespace has wrapped around, then we have the possibility of collisions.
+ * In that case, we may use this function to validate whether or not we
+ * should trust the nextCNID value in the hfs mount point.
+ *
+ * If we didn't do this, then it would be possible for a cnode that is no longer backed
+ * by anything on-disk (C_NOEXISTS) to still exist in the hash along with its
+ * vnode. The cat_create routine could then create a new entry in the catalog
+ * re-using that CNID. Then subsequent hfs_getnewvnode calls will repeatedly fail
+ * trying to look it up/validate it because it is marked C_NOEXISTS. So we want
+ * to prevent that from happening as much as possible.
+ */
+ if (existence_only) {
+ result = 0;
+ break;
+ }
+
+ /* Skip cnodes that have been removed from the catalog */
+ if (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
+ break;
+ }
+ /* Skip cnodes being created or reclaimed. */
+ if (!ISSET(cp->c_hflag, H_ALLOC | H_TRANSIT | H_ATTACH)) {
+ result = callout(&cp->c_desc, &cp->c_attr, arg);
+ }
+ break;
+ }
+ hfs_chash_unlock(hfsmp);
+
+ return (result);
+}
+
+
+/*
+ * Use the device, fileid pair to find the incore cnode.
+ * If no cnode if found one is created
+ *
+ * If it is in core, but locked, wait for it.
+ *
+ * If the cnode is C_DELETED, then return NULL since that
+ * inum is no longer valid for lookups (open-unlinked file).
+ *
+ * If the cnode is C_DELETED but also marked C_RENAMED, then that means
+ * the cnode was renamed over and a new entry exists in its place. The caller
+ * should re-drive the lookup to get the newer entry. In that case, we'll still
+ * return NULL for the cnode, but also return GNV_CHASH_RENAMED in the output flags
+ * of this function to indicate the caller that they should re-drive.
+ */
+struct cnode *
+hfs_chash_getcnode(struct hfsmount *hfsmp, ino_t inum, struct vnode **vpp,
+ int wantrsrc, int skiplock, int *out_flags, int *hflags)
+{
+ struct cnode *cp;
+ struct cnode *ncp = NULL;
+ vnode_t vp;
+ u_int32_t vid;
+
+ /*
+ * Go through the hash list
+ * If a cnode is in the process of being cleaned out or being
+ * allocated, wait for it to be finished and then try again.
+ */
+loop:
+ hfs_chash_lock_spin(hfsmp);
+loop_with_lock:
+ for (cp = CNODEHASH(hfsmp, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
+ if (cp->c_fileid != inum)
+ continue;
/*
- * Try getting the desired vnode first. If
- * it isn't available then take a reference
- * on the other vnode.
+ * Wait if cnode is being created, attached to or reclaimed.
*/
+ if (ISSET(cp->c_hflag, H_ALLOC | H_ATTACH | H_TRANSIT)) {
+ SET(cp->c_hflag, H_WAITING);
+
+ (void) msleep(cp, &hfsmp->hfs_chash_mutex, PINOD,
+ "hfs_chash_getcnode", 0);
+ goto loop_with_lock;
+ }
vp = wantrsrc ? cp->c_rsrc_vp : cp->c_vp;
- if (vp == NULLVP)
- vp = wantrsrc ? cp->c_vp : cp->c_rsrc_vp;
- if (vp == NULLVP)
- panic("hfs_chashget: orphaned cnode in hash");
+ if (vp == NULL) {
+ /*
+ * The desired vnode isn't there so tag the cnode.
+ */
+ SET(cp->c_hflag, H_ATTACH);
+ *hflags |= H_ATTACH;
- simple_lock(&vp->v_interlock);
- simple_unlock(&hfs_chash_slock);
- if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p))
- goto loop;
- else if (cp->c_flag & C_NOEXISTS) {
+ hfs_chash_unlock(hfsmp);
+ } else {
+ vid = vnode_vid(vp);
+
+ hfs_chash_unlock(hfsmp);
+
+ if (vnode_getwithvid(vp, vid))
+ goto loop;
+ }
+ if (ncp) {
/*
- * While we were blocked the cnode got deleted.
+ * someone else won the race to create
+ * this cnode and add it to the hash
+ * just dump our allocation
*/
- vput(vp);
- goto loop;
+ FREE_ZONE(ncp, sizeof(struct cnode), M_HFSNODE);
+ ncp = NULL;
+ }
+
+ if (!skiplock) {
+ hfs_lock(cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_ALLOW_NOEXISTS);
}
- if (VNODE_IS_RSRC(vp))
- *rvpp = vp;
- else
- *vpp = vp;
/*
- * Note that vget can block before aquiring the
- * cnode lock. So we need to check if the vnode
- * we wanted was created while we blocked.
+ * Skip cnodes that are not in the name space anymore
+ * we need to check with the cnode lock held because
+ * we may have blocked acquiring the vnode ref or the
+ * lock on the cnode which would allow the node to be
+ * unlinked.
+ *
+ * Don't return a cnode in this case since the inum
+ * is no longer valid for lookups.
*/
- if (wantrsrc && *rvpp == NULL && cp->c_rsrc_vp) {
- error = vget(cp->c_rsrc_vp, 0, p);
- vput(*vpp); /* ref no longer needed */
- *vpp = NULL;
- if (error)
- goto loop;
- *rvpp = cp->c_rsrc_vp;
-
- } else if (!wantrsrc && *vpp == NULL && cp->c_vp) {
- error = vget(cp->c_vp, 0, p);
- vput(*rvpp); /* ref no longer needed */
- *rvpp = NULL;
- if (error)
- goto loop;
- *vpp = cp->c_vp;
+ if ((cp->c_flag & (C_NOEXISTS | C_DELETED)) && !wantrsrc) {
+ int renamed = 0;
+ if (cp->c_flag & C_RENAMED) {
+ renamed = 1;
+ }
+ if (!skiplock)
+ hfs_unlock(cp);
+ if (vp != NULLVP) {
+ vnode_put(vp);
+ } else {
+ hfs_chash_lock_spin(hfsmp);
+ CLR(cp->c_hflag, H_ATTACH);
+ *hflags &= ~H_ATTACH;
+ if (ISSET(cp->c_hflag, H_WAITING)) {
+ CLR(cp->c_hflag, H_WAITING);
+ wakeup((caddr_t)cp);
+ }
+ hfs_chash_unlock(hfsmp);
+ }
+ vp = NULL;
+ cp = NULL;
+ if (renamed) {
+ *out_flags = GNV_CHASH_RENAMED;
+ }
}
+ *vpp = vp;
return (cp);
}
- simple_unlock(&hfs_chash_slock);
- return (NULL);
+
+ /*
+ * Allocate a new cnode
+ */
+ if (skiplock && !wantrsrc)
+ panic("%s - should never get here when skiplock is set \n", __FUNCTION__);
+
+ if (ncp == NULL) {
+ hfs_chash_unlock(hfsmp);
+
+ MALLOC_ZONE(ncp, struct cnode *, sizeof(struct cnode), M_HFSNODE, M_WAITOK);
+ /*
+ * since we dropped the chash lock,
+ * we need to go back and re-verify
+ * that this node hasn't come into
+ * existence...
+ */
+ goto loop;
+ }
+ hfs_chash_lock_convert(hfsmp);
+
+ bzero(ncp, sizeof(struct cnode));
+ SET(ncp->c_hflag, H_ALLOC);
+ *hflags |= H_ALLOC;
+ ncp->c_fileid = inum;
+ TAILQ_INIT(&ncp->c_hintlist); /* make the list empty */
+ TAILQ_INIT(&ncp->c_originlist);
+
+ lck_rw_init(&ncp->c_rwlock, hfs_rwlock_group, hfs_lock_attr);
+ if (!skiplock)
+ (void) hfs_lock(ncp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_DEFAULT);
+
+ /* Insert the new cnode with it's H_ALLOC flag set */
+ LIST_INSERT_HEAD(CNODEHASH(hfsmp, inum), ncp, c_hash);
+ hfs_chash_unlock(hfsmp);
+
+ *vpp = NULL;
+ return (ncp);
+}
+
+
+__private_extern__
+void
+hfs_chashwakeup(struct hfsmount *hfsmp, struct cnode *cp, int hflags)
+{
+ hfs_chash_lock_spin(hfsmp);
+
+ CLR(cp->c_hflag, hflags);
+
+ if (ISSET(cp->c_hflag, H_WAITING)) {
+ CLR(cp->c_hflag, H_WAITING);
+ wakeup((caddr_t)cp);
+ }
+ hfs_chash_unlock(hfsmp);
}
/*
- * Insert a cnode into the hash table.
+ * Re-hash two cnodes in the hash table.
*/
__private_extern__
void
-hfs_chashinsert(struct cnode *cp)
+hfs_chash_rehash(struct hfsmount *hfsmp, struct cnode *cp1, struct cnode *cp2)
{
- if (cp->c_fileid == 0)
- panic("hfs_chashinsert: trying to insert file id 0");
- simple_lock(&hfs_chash_slock);
- LIST_INSERT_HEAD(CNODEHASH(cp->c_dev, cp->c_fileid), cp, c_hash);
- simple_unlock(&hfs_chash_slock);
+ hfs_chash_lock_spin(hfsmp);
+
+ LIST_REMOVE(cp1, c_hash);
+ LIST_REMOVE(cp2, c_hash);
+ LIST_INSERT_HEAD(CNODEHASH(hfsmp, cp1->c_fileid), cp1, c_hash);
+ LIST_INSERT_HEAD(CNODEHASH(hfsmp, cp2->c_fileid), cp2, c_hash);
+
+ hfs_chash_unlock(hfsmp);
}
* Remove a cnode from the hash table.
*/
__private_extern__
+int
+hfs_chashremove(struct hfsmount *hfsmp, struct cnode *cp)
+{
+ hfs_chash_lock_spin(hfsmp);
+
+ /* Check if a vnode is getting attached */
+ if (ISSET(cp->c_hflag, H_ATTACH)) {
+ hfs_chash_unlock(hfsmp);
+ return (EBUSY);
+ }
+ if (cp->c_hash.le_next || cp->c_hash.le_prev) {
+ LIST_REMOVE(cp, c_hash);
+ cp->c_hash.le_next = NULL;
+ cp->c_hash.le_prev = NULL;
+ }
+ hfs_chash_unlock(hfsmp);
+
+ return (0);
+}
+
+/*
+ * Remove a cnode from the hash table and wakeup any waiters.
+ */
+__private_extern__
void
-hfs_chashremove(struct cnode *cp)
+hfs_chash_abort(struct hfsmount *hfsmp, struct cnode *cp)
{
- simple_lock(&hfs_chash_slock);
+ hfs_chash_lock_spin(hfsmp);
+
LIST_REMOVE(cp, c_hash);
cp->c_hash.le_next = NULL;
cp->c_hash.le_prev = NULL;
- simple_unlock(&hfs_chash_slock);
+
+ CLR(cp->c_hflag, H_ATTACH | H_ALLOC);
+ if (ISSET(cp->c_hflag, H_WAITING)) {
+ CLR(cp->c_hflag, H_WAITING);
+ wakeup((caddr_t)cp);
+ }
+ hfs_chash_unlock(hfsmp);
+}
+
+
+/*
+ * mark a cnode as in transition
+ */
+__private_extern__
+void
+hfs_chash_mark_in_transit(struct hfsmount *hfsmp, struct cnode *cp)
+{
+ hfs_chash_lock_spin(hfsmp);
+
+ SET(cp->c_hflag, H_TRANSIT);
+
+ hfs_chash_unlock(hfsmp);
}
+/* Search a cnode in the hash. This function does not return cnode which
+ * are getting created, destroyed or in transition. Note that this function
+ * does not acquire the cnode hash mutex, and expects the caller to acquire it.
+ * On success, returns pointer to the cnode found. On failure, returns NULL.
+ */
+static
+struct cnode *
+hfs_chash_search_cnid(struct hfsmount *hfsmp, cnid_t cnid)
+{
+ struct cnode *cp;
+
+ for (cp = CNODEHASH(hfsmp, cnid)->lh_first; cp; cp = cp->c_hash.le_next) {
+ if (cp->c_fileid == cnid) {
+ break;
+ }
+ }
+
+ /* If cnode is being created or reclaimed, return error. */
+ if (cp && ISSET(cp->c_hflag, H_ALLOC | H_TRANSIT | H_ATTACH)) {
+ cp = NULL;
+ }
+
+ return cp;
+}
+
+/* Search a cnode corresponding to given device and ID in the hash. If the
+ * found cnode has kHFSHasChildLinkBit cleared, set it. If the cnode is not
+ * found, no new cnode is created and error is returned.
+ *
+ * Return values -
+ * -1 : The cnode was not found.
+ * 0 : The cnode was found, and the kHFSHasChildLinkBit was already set.
+ * 1 : The cnode was found, the kHFSHasChildLinkBit was not set, and the
+ * function had to set that bit.
+ */
+__private_extern__
+int
+hfs_chash_set_childlinkbit(struct hfsmount *hfsmp, cnid_t cnid)
+{
+ int retval = -1;
+ struct cnode *cp;
+
+ hfs_chash_lock_spin(hfsmp);
+
+ cp = hfs_chash_search_cnid(hfsmp, cnid);
+ if (cp) {
+ if (cp->c_attr.ca_recflags & kHFSHasChildLinkMask) {
+ retval = 0;
+ } else {
+ cp->c_attr.ca_recflags |= kHFSHasChildLinkMask;
+ retval = 1;
+ }
+ }
+ hfs_chash_unlock(hfsmp);
+
+ return retval;
+}
projects / apple / xnu.git / blobdiff