xnu-2422.115.4.tar.gz

[apple/xnu.git] / bsd / hfs / hfs_chash.c

diff --git a/bsd/hfs/hfs_chash.c b/bsd/hfs/hfs_chash.c
index c93b1f1a48d984e3918556851730a846965bcb9c..b162a53b2cd502f53e3f615ba168a3988eef6793 100644 (file)
--- a/bsd/hfs/hfs_chash.c
+++ b/bsd/hfs/hfs_chash.c
@@ -1,23 +1,29 @@
 /*
 /*

- * Copyright (c) 2002-2005 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2002-2012 Apple Inc. All rights reserved.

  *
  *

- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  * 
  * 

- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * 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. 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.

  * 
  * 

- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * 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

  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.

  * 
  * 

- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
 
 /*
  */
 
 /*


@@ -76,14 +82,8 @@ lck_grp_t * chash_lck_grp;
 lck_grp_attr_t * chash_lck_grp_attr;
 lck_attr_t * chash_lck_attr;
 
 lck_grp_attr_t * chash_lck_grp_attr;
 lck_attr_t * chash_lck_attr;
 

-/*
- * 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])

 
 

-lck_mtx_t  hfs_chash_mutex;
+#define CNODEHASH(hfsmp, inum) (&hfsmp->hfs_cnodehashtbl[(inum) & hfsmp->hfs_cnodehash])

 
 
 /*
 
 
 /*


@@ -93,13 +93,47 @@ __private_extern__
 void
 hfs_chashinit()
 {
 void
 hfs_chashinit()
 {

-       cnodehashtbl = hashinit(desiredvnodes, M_HFSMNT, &cnodehash);
-

        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();
        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);

 
 

-       lck_mtx_init(&hfs_chash_mutex, chash_lck_grp, chash_lck_attr);
+       FREE(hfsmp->hfs_cnodehashtbl, M_HFSMNT);

 }
 
 
 }
 
 


@@ -108,14 +142,13 @@ hfs_chashinit()
  *
  * If it is in core, but locked, wait for it.
  */
  *
  * If it is in core, but locked, wait for it.
  */

-__private_extern__

 struct vnode *
 struct vnode *

-hfs_chash_getvnode(dev_t dev, ino_t inum, int wantrsrc, int skiplock)
+hfs_chash_getvnode(struct hfsmount *hfsmp, ino_t inum, int wantrsrc, int skiplock, int allow_deleted)

 {
        struct cnode *cp;
        struct vnode *vp;
        int error;
 {
        struct cnode *cp;
        struct vnode *vp;
        int error;

-       uint32_t vid;
+       u_int32_t vid;

 
        /* 
         * Go through the hash list
 
        /* 
         * Go through the hash list


@@ -123,34 +156,26 @@ hfs_chash_getvnode(dev_t dev, ino_t inum, int wantrsrc, int skiplock)
         * allocated, wait for it to be finished and then try again.
         */
 loop:
         * allocated, wait for it to be finished and then try again.
         */
 loop:

-       lck_mtx_lock(&hfs_chash_mutex);
-       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;
                /* 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);
 
                        continue;
                /* 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, &hfs_chash_mutex, PDROP | PINOD,
+                       (void) msleep(cp, &hfsmp->hfs_chash_mutex, PDROP | PINOD,

                                      "hfs_chash_getvnode", 0);
                        goto loop;
                }
                                      "hfs_chash_getvnode", 0);
                        goto loop;
                }

-               /*
-                * Skip cnodes that are not in the name space anymore
-                * note that this check is done outside of the proper
-                * lock to catch nodes already in this state... this
-                * state must be rechecked after we acquire the cnode lock
-                */
-               if (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
-                       continue;
-               }

                /* Obtain the desired vnode. */
                vp = wantrsrc ? cp->c_rsrc_vp : cp->c_vp;
                if (vp == NULLVP)
                        goto exit;
 
                vid = vnode_vid(vp);
                /* Obtain the desired vnode. */
                vp = wantrsrc ? cp->c_rsrc_vp : cp->c_vp;
                if (vp == NULLVP)
                        goto exit;
 
                vid = vnode_vid(vp);

-               lck_mtx_unlock(&hfs_chash_mutex);
+               hfs_chash_unlock(hfsmp);

 
                if ((error = vnode_getwithvid(vp, vid))) {
                        /*
 
                if ((error = vnode_getwithvid(vp, vid))) {
                        /*


@@ -159,42 +184,45 @@ loop:
                         */
                        return (NULL);
                }
                         */
                        return (NULL);
                }

-               if (!skiplock && hfs_lock(cp, HFS_EXCLUSIVE_LOCK) != 0) {
+               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
                        vnode_put(vp);
                        return (NULL);
                }
 
                /*
                 * Skip cnodes that are not in the name space anymore

-                * we need to check again 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
+                * 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 (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
-                       if (!skiplock)
-                               hfs_unlock(cp);
-                       vnode_put(vp);
-
-                       return (NULL);
-               }                       
+               if (!allow_deleted) {
+                       if (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
+                               if (!skiplock) {
+                                       hfs_unlock(cp);
+                               }
+                               vnode_put(vp);
+                               return (NULL);
+                       }                       
+               }

                return (vp);
        }
 exit:
                return (vp);
        }
 exit:

-       lck_mtx_unlock(&hfs_chash_mutex);
+       hfs_chash_unlock(hfsmp);

        return (NULL);
 }
 
 
 /*
        return (NULL);
 }
 
 
 /*

- * Use the device, fileid pair to find the incore cnode.
- * If no cnode if found one is created
+ * Use the device, fileid pair to snoop an incore cnode.

  *
  *

- * If it is in core, but locked, wait for it.
+ * 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.
+ * 

  */
  */

-__private_extern__

 int
 int

-hfs_chash_snoop(dev_t dev, ino_t inum, int (*callout)(const struct cat_desc *,
+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;
                 const struct cat_attr *, void *), void * arg)
 {
        struct cnode *cp;


@@ -205,17 +233,43 @@ hfs_chash_snoop(dev_t dev, ino_t inum, int (*callout)(const struct cat_desc *,
         * If a cnode is in the process of being cleaned out or being
         * allocated, wait for it to be finished and then try again.
         */
         * If a cnode is in the process of being cleaned out or being
         * allocated, wait for it to be finished and then try again.
         */

-       lck_mtx_lock(&hfs_chash_mutex);
-       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(hfsmp);
+
+       for (cp = CNODEHASH(hfsmp, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
+               if (cp->c_fileid != inum)

                        continue;
                        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;
        }
                /* 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;
        }

-       lck_mtx_unlock(&hfs_chash_mutex);
+       hfs_chash_unlock(hfsmp);
+

        return (result);
 }
 
        return (result);
 }
 


@@ -225,15 +279,24 @@ hfs_chash_snoop(dev_t dev, ino_t inum, int (*callout)(const struct cat_desc *,
  * If no cnode if found one is created
  *
  * If it is in core, but locked, wait for it.
  * 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.

  */
  */

-__private_extern__

 struct cnode *
 struct cnode *

-hfs_chash_getcnode(dev_t dev, ino_t inum, struct vnode **vpp, int wantrsrc, int skiplock)
+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;
 {
        struct cnode    *cp;
        struct cnode    *ncp = NULL;
        vnode_t         vp;

-       uint32_t        vid;
+       u_int32_t       vid;

 
        /* 
         * Go through the hash list
 
        /* 
         * Go through the hash list


@@ -241,11 +304,11 @@ hfs_chash_getcnode(dev_t dev, ino_t inum, struct vnode **vpp, int wantrsrc, int
         * allocated, wait for it to be finished and then try again.
         */
 loop:
         * allocated, wait for it to be finished and then try again.
         */
 loop:

-       lck_mtx_lock(&hfs_chash_mutex);
+       hfs_chash_lock_spin(hfsmp);

 
 loop_with_lock:
 
 loop_with_lock:

-       for (cp = CNODEHASH(dev, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
-               if ((cp->c_fileid != inum) || (cp->c_dev != dev))
+       for (cp = CNODEHASH(hfsmp, inum)->lh_first; cp; cp = cp->c_hash.le_next) {
+               if (cp->c_fileid != inum)

                        continue;
                /*
                 * Wait if cnode is being created, attached to or reclaimed.
                        continue;
                /*
                 * Wait if cnode is being created, attached to or reclaimed.


@@ -253,70 +316,75 @@ loop_with_lock:
                if (ISSET(cp->c_hflag, H_ALLOC | H_ATTACH | H_TRANSIT)) {
                        SET(cp->c_hflag, H_WAITING);
 
                if (ISSET(cp->c_hflag, H_ALLOC | H_ATTACH | H_TRANSIT)) {
                        SET(cp->c_hflag, H_WAITING);
 

-                       (void) msleep(cp, &hfs_chash_mutex, PINOD,
+                       (void) msleep(cp, &hfsmp->hfs_chash_mutex, PINOD,

                                      "hfs_chash_getcnode", 0);
                        goto loop_with_lock;
                }
                                      "hfs_chash_getcnode", 0);
                        goto loop_with_lock;
                }

-               /*
-                * Skip cnodes that are not in the name space anymore
-                * note that this check is done outside of the proper
-                * lock to catch nodes already in this state... this
-                * state must be rechecked after we acquire the cnode lock
-                */
-               if (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
-                       continue;
-               }

                vp = wantrsrc ? cp->c_rsrc_vp : cp->c_vp;
                if (vp == NULL) {
                        /*
                         * The desired vnode isn't there so tag the cnode.
                         */
                        SET(cp->c_hflag, H_ATTACH);
                vp = wantrsrc ? cp->c_rsrc_vp : cp->c_vp;
                if (vp == NULL) {
                        /*
                         * The desired vnode isn't there so tag the cnode.
                         */
                        SET(cp->c_hflag, H_ATTACH);

+                       *hflags |= H_ATTACH;

 
 

-                       lck_mtx_unlock(&hfs_chash_mutex);
+                       hfs_chash_unlock(hfsmp);

                } else {
                        vid = vnode_vid(vp);
 
                } else {
                        vid = vnode_vid(vp);
 

-                       lck_mtx_unlock(&hfs_chash_mutex);
+                       hfs_chash_unlock(hfsmp);

 
                        if (vnode_getwithvid(vp, vid))
                                goto loop;
                }
                if (ncp) {
 
                        if (vnode_getwithvid(vp, vid))
                                goto loop;
                }
                if (ncp) {

-                       /*
+                       /*

                         * someone else won the race to create
                         * this cnode and add it to the hash
                         * just dump our allocation
                         */
                         * someone else won the race to create
                         * this cnode and add it to the hash
                         * just dump our allocation
                         */

-                       FREE_ZONE(ncp, sizeof(struct cnode), M_HFSNODE);
+                       FREE_ZONE(ncp, sizeof(struct cnode), M_HFSNODE);

                        ncp = NULL;
                }
                        ncp = NULL;
                }

-               if (!skiplock && hfs_lock(cp, HFS_EXCLUSIVE_LOCK) != 0) {
-                       if (vp != NULLVP)
-                               vnode_put(vp);
-                       lck_mtx_lock(&hfs_chash_mutex);

 
 

-                       if (vp == NULLVP)
-                               CLR(cp->c_hflag, H_ATTACH);
-                       goto loop_with_lock;
+               if (!skiplock) {
+                       hfs_lock(cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_ALLOW_NOEXISTS);

                }
                }

+

                /*
                 * Skip cnodes that are not in the name space anymore
                /*
                 * Skip cnodes that are not in the name space anymore

-                * we need to check again 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
+                * 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 (cp->c_flag & (C_NOEXISTS | C_DELETED)) {
+               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 (!skiplock)
                                hfs_unlock(cp);

-                       if (vp != NULLVP)
+                       if (vp != NULLVP) {

                                vnode_put(vp);
                                vnode_put(vp);

-                       lck_mtx_lock(&hfs_chash_mutex);
-
-                       if (vp == NULLVP)
-                               CLR(cp->c_hflag, H_ATTACH);
-                       goto loop_with_lock;
+                       } 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);
                }
                *vpp = vp;
                return (cp);


@@ -325,11 +393,11 @@ loop_with_lock:
        /* 
         * Allocate a new cnode
         */
        /* 
         * Allocate a new cnode
         */

-       if (skiplock)
+       if (skiplock && !wantrsrc)

                panic("%s - should never get here when skiplock is set \n", __FUNCTION__);
 
        if (ncp == NULL) {
                panic("%s - should never get here when skiplock is set \n", __FUNCTION__);
 
        if (ncp == NULL) {

-               lck_mtx_unlock(&hfs_chash_mutex);
+               hfs_chash_unlock(hfsmp);

 
                MALLOC_ZONE(ncp, struct cnode *, sizeof(struct cnode), M_HFSNODE, M_WAITOK);
                /*
 
                MALLOC_ZONE(ncp, struct cnode *, sizeof(struct cnode), M_HFSNODE, M_WAITOK);
                /*


@@ -340,19 +408,22 @@ loop_with_lock:
                 */
                goto loop;
        }
                 */
                goto loop;
        }

+       hfs_chash_lock_convert(hfsmp);
+

        bzero(ncp, sizeof(struct cnode));
        SET(ncp->c_hflag, H_ALLOC);
        bzero(ncp, sizeof(struct cnode));
        SET(ncp->c_hflag, H_ALLOC);

+       *hflags |= H_ALLOC;

        ncp->c_fileid = inum;
        ncp->c_fileid = inum;

-       ncp->c_dev = dev;

        TAILQ_INIT(&ncp->c_hintlist); /* make the list empty */
        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)
 
        lck_rw_init(&ncp->c_rwlock, hfs_rwlock_group, hfs_lock_attr);
        if (!skiplock)

-               (void) hfs_lock(ncp, HFS_EXCLUSIVE_LOCK);
+               (void) hfs_lock(ncp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_DEFAULT);

 
        /* Insert the new cnode with it's H_ALLOC flag set */
 
        /* Insert the new cnode with it's H_ALLOC flag set */

-       LIST_INSERT_HEAD(CNODEHASH(dev, inum), ncp, c_hash);
-       lck_mtx_unlock(&hfs_chash_mutex);
+       LIST_INSERT_HEAD(CNODEHASH(hfsmp, inum), ncp, c_hash);
+       hfs_chash_unlock(hfsmp);

 
        *vpp = NULL;
        return (ncp);
 
        *vpp = NULL;
        return (ncp);


@@ -361,9 +432,9 @@ loop_with_lock:
 
 __private_extern__
 void
 
 __private_extern__
 void

-hfs_chashwakeup(struct cnode *cp, int hflags)
+hfs_chashwakeup(struct hfsmount *hfsmp, struct cnode *cp, int hflags)

 {
 {

-       lck_mtx_lock(&hfs_chash_mutex);
+       hfs_chash_lock_spin(hfsmp);

 
        CLR(cp->c_hflag, hflags);
 
 
        CLR(cp->c_hflag, hflags);
 


@@ -371,7 +442,7 @@ hfs_chashwakeup(struct cnode *cp, int hflags)
                CLR(cp->c_hflag, H_WAITING);
                wakeup((caddr_t)cp);
        }
                CLR(cp->c_hflag, H_WAITING);
                wakeup((caddr_t)cp);
        }

-       lck_mtx_unlock(&hfs_chash_mutex);
+       hfs_chash_unlock(hfsmp);

 }
 
 
 }
 
 


@@ -380,16 +451,16 @@ hfs_chashwakeup(struct cnode *cp, int hflags)
  */
 __private_extern__
 void
  */
 __private_extern__
 void

-hfs_chash_rehash(struct cnode *cp1, struct cnode *cp2)
+hfs_chash_rehash(struct hfsmount *hfsmp, struct cnode *cp1, struct cnode *cp2)

 {
 {

-       lck_mtx_lock(&hfs_chash_mutex);
+       hfs_chash_lock_spin(hfsmp);

 
        LIST_REMOVE(cp1, c_hash);
        LIST_REMOVE(cp2, c_hash);
 
        LIST_REMOVE(cp1, c_hash);
        LIST_REMOVE(cp2, c_hash);

-       LIST_INSERT_HEAD(CNODEHASH(cp1->c_dev, cp1->c_fileid), cp1, c_hash);
-       LIST_INSERT_HEAD(CNODEHASH(cp2->c_dev, cp2->c_fileid), 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);

 
 

-       lck_mtx_unlock(&hfs_chash_mutex);
+       hfs_chash_unlock(hfsmp);

 }
 
 
 }
 
 


@@ -398,20 +469,22 @@ hfs_chash_rehash(struct cnode *cp1, struct cnode *cp2)
  */
 __private_extern__
 int
  */
 __private_extern__
 int

-hfs_chashremove(struct cnode *cp)
+hfs_chashremove(struct hfsmount *hfsmp, struct cnode *cp)

 {
 {

-       lck_mtx_lock(&hfs_chash_mutex);
+       hfs_chash_lock_spin(hfsmp);

 
        /* Check if a vnode is getting attached */
        if (ISSET(cp->c_hflag, H_ATTACH)) {
 
        /* Check if a vnode is getting attached */
        if (ISSET(cp->c_hflag, H_ATTACH)) {

-               lck_mtx_unlock(&hfs_chash_mutex);
+               hfs_chash_unlock(hfsmp);

                return (EBUSY);
        }
                return (EBUSY);
        }

-       LIST_REMOVE(cp, c_hash);
-       cp->c_hash.le_next = NULL;
-       cp->c_hash.le_prev = NULL;
-       
-       lck_mtx_unlock(&hfs_chash_mutex);
+       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);
 }
 
        return (0);
 }
 


@@ -420,9 +493,9 @@ hfs_chashremove(struct cnode *cp)
  */
 __private_extern__
 void
  */
 __private_extern__
 void

-hfs_chash_abort(struct cnode *cp)
+hfs_chash_abort(struct hfsmount *hfsmp, struct cnode *cp)

 {
 {

-       lck_mtx_lock(&hfs_chash_mutex);
+       hfs_chash_lock_spin(hfsmp);

 
        LIST_REMOVE(cp, c_hash);
        cp->c_hash.le_next = NULL;
 
        LIST_REMOVE(cp, c_hash);
        cp->c_hash.le_next = NULL;


@@ -433,20 +506,78 @@ hfs_chash_abort(struct cnode *cp)
                CLR(cp->c_hflag, H_WAITING);
                wakeup((caddr_t)cp);
        }
                CLR(cp->c_hflag, H_WAITING);
                wakeup((caddr_t)cp);
        }

-       lck_mtx_unlock(&hfs_chash_mutex);
+       hfs_chash_unlock(hfsmp);

 }
 
 
 /*
 }
 
 
 /*

- * mark a cnode as in transistion
+ * mark a cnode as in transition

  */
 __private_extern__
 void
  */
 __private_extern__
 void

-hfs_chash_mark_in_transit(struct cnode *cp)
+hfs_chash_mark_in_transit(struct hfsmount *hfsmp, struct cnode *cp)

 {
 {

-       lck_mtx_lock(&hfs_chash_mutex);
+       hfs_chash_lock_spin(hfsmp);

 
         SET(cp->c_hflag, H_TRANSIT);
 
 
         SET(cp->c_hflag, H_TRANSIT);
 

-       lck_mtx_unlock(&hfs_chash_mutex);
+       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;

 }
 }