/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. * * Copyright (c) 1983,1984,1985,1986,1987,1988,1989 AT&T. * All rights reserved. */ /* * Node hash implementation borrowed from NFS. * See: uts/common/fs/nfs/nfs_subr.c */ #include #include #include #include #include #include #include #include #ifdef APPLE #include #include #include #else #include #endif #include #include #include #include #include #include #include /* * The hash queues for the access to active and cached smbnodes * are organized as doubly linked lists. A reader/writer lock * for each hash bucket is used to control access and to synchronize * lookups, additions, and deletions from the hash queue. * * The smbnode freelist is organized as a doubly linked list with * a head pointer. Additions and deletions are synchronized via * a single mutex. * * In order to add an smbnode to the free list, it must be hashed into * a hash queue and the exclusive lock to the hash queue be held. * If an smbnode is not hashed into a hash queue, then it is destroyed * because it represents no valuable information that can be reused * about the file. The exclusive lock to the hash queue must be * held in order to prevent a lookup in the hash queue from finding * the smbnode and using it and assuming that the smbnode is not on the * freelist. The lookup in the hash queue will have the hash queue * locked, either exclusive or shared. * * The vnode reference count for each smbnode is not allowed to drop * below 1. This prevents external entities, such as the VM * subsystem, from acquiring references to vnodes already on the * freelist and then trying to place them back on the freelist * when their reference is released. This means that the when an * smbnode is looked up in the hash queues, then either the smbnode * is removed from the freelist and that reference is tranfered to * the new reference or the vnode reference count must be incremented * accordingly. The mutex for the freelist must be held in order to * accurately test to see if the smbnode is on the freelist or not. * The hash queue lock might be held shared and it is possible that * two different threads may race to remove the smbnode from the * freelist. This race can be resolved by holding the mutex for the * freelist. Please note that the mutex for the freelist does not * need to held if the smbnode is not on the freelist. It can not be * placed on the freelist due to the requirement that the thread * putting the smbnode on the freelist must hold the exclusive lock * to the hash queue and the thread doing the lookup in the hash * queue is holding either a shared or exclusive lock to the hash * queue. * * The lock ordering is: * * hash bucket lock -> vnode lock * hash bucket lock -> freelist lock */ static rhashq_t *smbtable; static kmutex_t smbfreelist_lock; static smbnode_t *smbfreelist = NULL; static ulong_t smbnodenew = 0; long nsmbnode = 0; static int smbtablesize; static int smbtablemask; static int smbhashlen = 4; static struct kmem_cache *smbnode_cache; /* * Mutex to protect the following variables: * smbfs_major * smbfs_minor */ kmutex_t smbfs_minor_lock; int smbfs_major; int smbfs_minor; /* * Local functions. * Not static, to aid debugging. */ void smb_rmfree(smbnode_t *); void smbinactive(smbnode_t *); void smb_rmhash_locked(smbnode_t *); void smb_destroy_node(smbnode_t *); void smbfs_kmem_reclaim(void *cdrarg); smbnode_t *smbhashfind(struct vfs *, const char *, int, rhashq_t *); static vnode_t *make_smbnode(vfs_t *, char *, int, rhashq_t *, int *); /* * Free the resources associated with an smbnode. * Note: This is different from smbfs_inactive * * NFS: nfs_subr.c:rinactive */ void smbinactive(smbnode_t *np) { if (np->n_rpath) { kmem_free(np->n_rpath, np->n_rplen + 1); np->n_rpath = NULL; } } /* * Return a vnode for the given CIFS directory and filename. * If no smbnode exists for this fhandle, create one and put it * into the hash queues. If the smbnode for this fhandle * already exists, return it. * * Note: make_smbnode() may upgrade the hash bucket lock to exclusive. * * NFS: nfs_subr.c:makenfsnode */ vnode_t * smbfs_make_node( vfs_t *vfsp, const char *dir, int dirlen, const char *name, int nmlen, char sep, struct smbfattr *fap) { char *rpath; int rplen, idx; uint32_t hash; rhashq_t *rhtp; smbnode_t *np; vnode_t *vp; #ifdef NOT_YET vattr_t va; #endif int newnode; /* * Build the full path name in allocated memory * so we have it for lookup, etc. Note the * special case at the root (dir=="\\", dirlen==1) * where this does not add a slash separator. * To do that would make a double slash, which * has special meaning in CIFS. * * ToDo: Would prefer to allocate a remote path * only when we will create a new node. */ if (dirlen <= 1 && sep == '\\') sep = '\0'; /* no slash */ /* Compute the length of rpath and allocate. */ rplen = dirlen; if (sep) rplen++; if (name) rplen += nmlen; rpath = kmem_alloc(rplen + 1, KM_SLEEP); /* Fill in rpath */ bcopy(dir, rpath, dirlen); if (sep) rpath[dirlen++] = sep; if (name) bcopy(name, &rpath[dirlen], nmlen); rpath[rplen] = 0; hash = smbfs_hash(rpath, rplen); idx = hash & smbtablemask; rhtp = &smbtable[idx]; rw_enter(&rhtp->r_lock, RW_READER); vp = make_smbnode(vfsp, rpath, rplen, rhtp, &newnode); np = VTOSMB(vp); np->n_ino = hash; /* Equivalent to: smbfs_getino() */ /* * Note: make_smbnode keeps a reference to rpath in * new nodes it creates, so only free when we found * an existing node. */ if (!newnode) { kmem_free(rpath, rplen + 1); rpath = NULL; } if (fap == NULL) { #ifdef NOT_YET if (newnode) { PURGE_ATTRCACHE(vp); } #endif rw_exit(&rhtp->r_lock); return (vp); } /* Have SMB attributes. */ vp->v_type = (fap->fa_attr & SMB_FA_DIR) ? VDIR : VREG; /* XXX: np->n_ino = fap->fa_ino; see above */ np->r_size = fap->fa_size; /* XXX: np->r_attr = *fap here instead? */ np->r_atime = fap->fa_atime; np->r_ctime = fap->fa_ctime; np->r_mtime = fap->fa_mtime; #ifdef NOT_YET if (!newnode) { rw_exit(&rhtp->r_lock); (void) nfs_cache_fattr(vp, attr, &va, t, cr); } else { if (attr->na_type < NFNON || attr->na_type > NFSOC) vp->v_type = VBAD; else vp->v_type = n2v_type(attr); vp->v_rdev = makedevice(attr->rdev.specdata1, attr->rdev.specdata2); nfs_attrcache(vp, attr, t); rw_exit(&rhtp->r_lock); } #else rw_exit(&rhtp->r_lock); #endif return (vp); } /* * NFS: nfs_subr.c:rtablehash * We use smbfs_hash(). */ /* * Find or create an smbnode. * NFS: nfs_subr.c:make_rnode */ static vnode_t * make_smbnode( vfs_t *vfsp, char *rpath, int rplen, rhashq_t *rhtp, int *newnode) { smbnode_t *np; smbnode_t *tnp; vnode_t *vp; smbmntinfo_t *mi; ASSERT(RW_READ_HELD(&rhtp->r_lock)); mi = VFTOSMI(vfsp); start: np = smbhashfind(vfsp, rpath, rplen, rhtp); if (np != NULL) { vp = SMBTOV(np); *newnode = 0; return (vp); } /* Note: will retake this lock below. */ rw_exit(&rhtp->r_lock); /* * see if we can find something on the freelist */ mutex_enter(&smbfreelist_lock); if (smbfreelist != NULL && smbnodenew >= nsmbnode) { np = smbfreelist; smb_rmfree(np); mutex_exit(&smbfreelist_lock); vp = SMBTOV(np); if (np->r_flags & RHASHED) { rw_enter(&np->r_hashq->r_lock, RW_WRITER); mutex_enter(&vp->v_lock); if (vp->v_count > 1) { vp->v_count--; mutex_exit(&vp->v_lock); rw_exit(&np->r_hashq->r_lock); rw_enter(&rhtp->r_lock, RW_READER); goto start; } mutex_exit(&vp->v_lock); smb_rmhash_locked(np); rw_exit(&np->r_hashq->r_lock); } smbinactive(np); mutex_enter(&vp->v_lock); if (vp->v_count > 1) { vp->v_count--; mutex_exit(&vp->v_lock); rw_enter(&rhtp->r_lock, RW_READER); goto start; } mutex_exit(&vp->v_lock); vn_invalid(vp); /* * destroy old locks before bzero'ing and * recreating the locks below. */ smbfs_rw_destroy(&np->r_rwlock); smbfs_rw_destroy(&np->r_lkserlock); mutex_destroy(&np->r_statelock); cv_destroy(&np->r_cv); /* * Make sure that if smbnode is recycled then * VFS count is decremented properly before * reuse. */ VFS_RELE(vp->v_vfsp); vn_reinit(vp); } else { /* * allocate and initialize a new smbnode */ vnode_t *new_vp; mutex_exit(&smbfreelist_lock); np = kmem_cache_alloc(smbnode_cache, KM_SLEEP); new_vp = vn_alloc(KM_SLEEP); atomic_add_long((ulong_t *)&smbnodenew, 1); vp = new_vp; } /* Initialize smbnode_t */ bzero(np, sizeof (*np)); smbfs_rw_init(&np->r_rwlock, NULL, RW_DEFAULT, NULL); smbfs_rw_init(&np->r_lkserlock, NULL, RW_DEFAULT, NULL); mutex_init(&np->r_statelock, NULL, MUTEX_DEFAULT, NULL); cv_init(&np->r_cv, NULL, CV_DEFAULT, NULL); /* cv_init(&np->r_commit.c_cv, NULL, CV_DEFAULT, NULL); */ np->r_vnode = vp; np->n_mount = mi; np->r_hashq = rhtp; np->n_fid = SMB_FID_UNUSED; np->n_uid = UID_NOBODY; np->n_gid = GID_NOBODY; /* XXX: make attributes stale? */ #if 0 /* XXX dircache */ /* * We don't know if it's a directory yet. * Let the caller do this? XXX */ avl_create(&np->r_dir, compar, sizeof (rddir_cache), offsetof(rddir_cache, tree)); #endif /* Now fill in the vnode. */ vn_setops(vp, smbfs_vnodeops); vp->v_data = (caddr_t)np; VFS_HOLD(vfsp); vp->v_vfsp = vfsp; vp->v_type = VNON; /* * There is a race condition if someone else * alloc's the smbnode while no locks are held, so we * check again and recover if found. */ rw_enter(&rhtp->r_lock, RW_WRITER); tnp = smbhashfind(vfsp, rpath, rplen, rhtp); if (tnp != NULL) { vp = SMBTOV(tnp); *newnode = 0; rw_exit(&rhtp->r_lock); /* The node we were building goes on the free list. */ smb_addfree(np); rw_enter(&rhtp->r_lock, RW_READER); return (vp); } /* * Hash search identifies nodes by the full pathname, * so store that before linking in the hash list. * Note: caller allocates the rpath, and knows * about this reference when *newnode is set. */ np->n_rpath = rpath; np->n_rplen = rplen; smb_addhash(np); *newnode = 1; return (vp); } /* * smb_addfree * Put a smbnode on the free list. * * Normally called by smbfs_inactive, but also * called in here during cleanup operations. * * Smbnodes which were allocated above and beyond the normal limit * are immediately freed. * * NFS: nfs_subr.c:rp_addfree */ void smb_addfree(smbnode_t *np) { vnode_t *vp; struct vfs *vfsp; vp = SMBTOV(np); ASSERT(vp->v_count >= 1); ASSERT(np->r_freef == NULL && np->r_freeb == NULL); /* * If we have too many smbnodes allocated and there are no * references to this smbnode, or if the smbnode is no longer * accessible by it does not reside in the hash queues, * or if an i/o error occurred while writing to the file, * then just free it instead of putting it on the smbnode * freelist. */ vfsp = vp->v_vfsp; if (((smbnodenew > nsmbnode || !(np->r_flags & RHASHED) || np->r_error || (vfsp->vfs_flag & VFS_UNMOUNTED)) && np->r_count == 0)) { if (np->r_flags & RHASHED) { rw_enter(&np->r_hashq->r_lock, RW_WRITER); mutex_enter(&vp->v_lock); if (vp->v_count > 1) { vp->v_count--; mutex_exit(&vp->v_lock); rw_exit(&np->r_hashq->r_lock); return; /* * Will get another call later, * via smbfs_inactive. */ } mutex_exit(&vp->v_lock); smb_rmhash_locked(np); rw_exit(&np->r_hashq->r_lock); } smbinactive(np); /* * Recheck the vnode reference count. We need to * make sure that another reference has not been * acquired while we were not holding v_lock. The * smbnode is not in the smbnode hash queues, so the * only way for a reference to have been acquired * is for a VOP_PUTPAGE because the smbnode was marked * with RDIRTY or for a modified page. This * reference may have been acquired before our call * to smbinactive. The i/o may have been completed, * thus allowing smbinactive to complete, but the * reference to the vnode may not have been released * yet. In any case, the smbnode can not be destroyed * until the other references to this vnode have been * released. The other references will take care of * either destroying the smbnode or placing it on the * smbnode freelist. If there are no other references, * then the smbnode may be safely destroyed. */ mutex_enter(&vp->v_lock); if (vp->v_count > 1) { vp->v_count--; mutex_exit(&vp->v_lock); return; } mutex_exit(&vp->v_lock); smb_destroy_node(np); return; } /* * Lock the hash queue and then recheck the reference count * to ensure that no other threads have acquired a reference * to indicate that the smbnode should not be placed on the * freelist. If another reference has been acquired, then * just release this one and let the other thread complete * the processing of adding this smbnode to the freelist. */ rw_enter(&np->r_hashq->r_lock, RW_WRITER); mutex_enter(&vp->v_lock); if (vp->v_count > 1) { vp->v_count--; mutex_exit(&vp->v_lock); rw_exit(&np->r_hashq->r_lock); return; } mutex_exit(&vp->v_lock); /* * If there is no cached data or metadata for this file, then * put the smbnode on the front of the freelist so that it will * be reused before other smbnodes which may have cached data or * metadata associated with them. */ mutex_enter(&smbfreelist_lock); if (smbfreelist == NULL) { np->r_freef = np; np->r_freeb = np; smbfreelist = np; } else { np->r_freef = smbfreelist; np->r_freeb = smbfreelist->r_freeb; smbfreelist->r_freeb->r_freef = np; smbfreelist->r_freeb = np; } mutex_exit(&smbfreelist_lock); rw_exit(&np->r_hashq->r_lock); } /* * Remove an smbnode from the free list. * * The caller must be holding smbfreelist_lock and the smbnode * must be on the freelist. * * NFS: nfs_subr.c:rp_rmfree */ void smb_rmfree(smbnode_t *np) { ASSERT(MUTEX_HELD(&smbfreelist_lock)); ASSERT(np->r_freef != NULL && np->r_freeb != NULL); if (np == smbfreelist) { smbfreelist = np->r_freef; if (np == smbfreelist) smbfreelist = NULL; } np->r_freeb->r_freef = np->r_freef; np->r_freef->r_freeb = np->r_freeb; np->r_freef = np->r_freeb = NULL; } /* * Put a smbnode in the hash table. * * The caller must be holding the exclusive hash queue lock. * * NFS: nfs_subr.c:rp_addhash */ void smb_addhash(smbnode_t *np) { ASSERT(RW_WRITE_HELD(&np->r_hashq->r_lock)); ASSERT(!(np->r_flags & RHASHED)); np->r_hashf = np->r_hashq->r_hashf; np->r_hashq->r_hashf = np; np->r_hashb = (smbnode_t *)np->r_hashq; np->r_hashf->r_hashb = np; mutex_enter(&np->r_statelock); np->r_flags |= RHASHED; mutex_exit(&np->r_statelock); } /* * Remove a smbnode from the hash table. * * The caller must be holding the hash queue lock. * * NFS: nfs_subr.c:rp_rmhash_locked */ void smb_rmhash_locked(smbnode_t *np) { ASSERT(RW_WRITE_HELD(&np->r_hashq->r_lock)); ASSERT(np->r_flags & RHASHED); np->r_hashb->r_hashf = np->r_hashf; np->r_hashf->r_hashb = np->r_hashb; mutex_enter(&np->r_statelock); np->r_flags &= ~RHASHED; mutex_exit(&np->r_statelock); } /* * Remove a smbnode from the hash table. * * The caller must not be holding the hash queue lock. */ void smb_rmhash(smbnode_t *np) { rw_enter(&np->r_hashq->r_lock, RW_WRITER); smb_rmhash_locked(np); rw_exit(&np->r_hashq->r_lock); } /* * Lookup a smbnode by fhandle. * * The caller must be holding the hash queue lock, either shared or exclusive. * XXX: make static? * * NFS: nfs_subr.c:rfind */ smbnode_t * smbhashfind( struct vfs *vfsp, const char *rpath, int rplen, rhashq_t *rhtp) { smbnode_t *np; vnode_t *vp; ASSERT(RW_LOCK_HELD(&rhtp->r_lock)); for (np = rhtp->r_hashf; np != (smbnode_t *)rhtp; np = np->r_hashf) { vp = SMBTOV(np); if (vp->v_vfsp == vfsp && np->n_rplen == rplen && bcmp(np->n_rpath, rpath, rplen) == 0) { /* * remove smbnode from free list, if necessary. */ if (np->r_freef != NULL) { mutex_enter(&smbfreelist_lock); /* * If the smbnode is on the freelist, * then remove it and use that reference * as the new reference. Otherwise, * need to increment the reference count. */ if (np->r_freef != NULL) { smb_rmfree(np); mutex_exit(&smbfreelist_lock); } else { mutex_exit(&smbfreelist_lock); VN_HOLD(vp); } } else VN_HOLD(vp); return (np); } } return (NULL); } #ifdef SMB_VNODE_DEBUG int smb_check_table_debug = 1; #else /* SMB_VNODE_DEBUG */ int smb_check_table_debug = 0; #endif /* SMB_VNODE_DEBUG */ /* * Return 1 if there is a active vnode belonging to this vfs in the * smbtable cache. * * Several of these checks are done without holding the usual * locks. This is safe because destroy_smbtable(), smb_addfree(), * etc. will redo the necessary checks before actually destroying * any smbnodes. * * NFS: nfs_subr.c:check_rtable * * Debugging changes here relative to NFS. * Relatively harmless, so left 'em in. */ int smb_check_table(struct vfs *vfsp, smbnode_t *rtnp) { smbnode_t *np; vnode_t *vp; int index; int busycnt = 0; for (index = 0; index < smbtablesize; index++) { rw_enter(&smbtable[index].r_lock, RW_READER); for (np = smbtable[index].r_hashf; np != (smbnode_t *)(&smbtable[index]); np = np->r_hashf) { if (np == rtnp) continue; /* skip the root */ vp = SMBTOV(np); if (vp->v_vfsp != vfsp) continue; /* skip other mount */ /* Now the 'busy' checks: */ /* Not on the free list? */ if (np->r_freef == NULL) { SMBVDEBUG("!r_freef: node=0x%p, v_path=%s\n", (void *)np, vp->v_path); busycnt++; } /* Has dirty pages? */ if (vn_has_cached_data(vp) && (np->r_flags & RDIRTY)) { SMBVDEBUG("is dirty: node=0x%p, v_path=%s\n", (void *)np, vp->v_path); busycnt++; } /* Other refs? (not reflected in v_count) */ if (np->r_count > 0) { SMBVDEBUG("+r_count: node=0x%p, v_path=%s\n", (void *)np, vp->v_path); busycnt++; } if (busycnt && !smb_check_table_debug) break; } rw_exit(&smbtable[index].r_lock); } return (busycnt); } /* * Destroy inactive vnodes from the hash queues which belong to this * vfs. It is essential that we destroy all inactive vnodes during a * forced unmount as well as during a normal unmount. * * NFS: nfs_subr.c:destroy_rtable */ void smbfs_destroy_table(struct vfs *vfsp) { int index; smbnode_t *np; smbnode_t *rlist; smbnode_t *r_hashf; vnode_t *vp; rlist = NULL; for (index = 0; index < smbtablesize; index++) { rw_enter(&smbtable[index].r_lock, RW_WRITER); for (np = smbtable[index].r_hashf; np != (smbnode_t *)(&smbtable[index]); np = r_hashf) { /* save the hash pointer before destroying */ r_hashf = np->r_hashf; vp = SMBTOV(np); if (vp->v_vfsp == vfsp) { mutex_enter(&smbfreelist_lock); if (np->r_freef != NULL) { smb_rmfree(np); mutex_exit(&smbfreelist_lock); smb_rmhash_locked(np); np->r_hashf = rlist; rlist = np; } else mutex_exit(&smbfreelist_lock); } } rw_exit(&smbtable[index].r_lock); } for (np = rlist; np != NULL; np = rlist) { rlist = np->r_hashf; /* * This call to smb_addfree will end up destroying the * smbnode, but in a safe way with the appropriate set * of checks done. */ smb_addfree(np); } } /* * This routine destroys all the resources associated with the smbnode * and then the smbnode itself. * * NFS: nfs_subr.c:destroy_rnode */ void smb_destroy_node(smbnode_t *np) { vnode_t *vp; vfs_t *vfsp; vp = SMBTOV(np); vfsp = vp->v_vfsp; ASSERT(vp->v_count == 1); ASSERT(np->r_count == 0); ASSERT(np->r_mapcnt == 0); ASSERT(!(np->r_flags & RHASHED)); ASSERT(np->r_freef == NULL && np->r_freeb == NULL); atomic_add_long((ulong_t *)&smbnodenew, -1); vn_invalid(vp); vn_free(vp); kmem_cache_free(smbnode_cache, np); VFS_RELE(vfsp); } /* rflush? */ /* access cache */ /* client handles */ /* * initialize resources that are used by smbfs_subr.c * this is called from the _init() routine (by the way of smbfs_clntinit()) * * allocate and initialze smbfs hash table * NFS: nfs_subr.c:nfs_subrinit */ int smbfs_subrinit(void) { int i; ulong_t nsmbnode_max; /* * Allocate and initialize the smbnode hash queues */ if (nsmbnode <= 0) nsmbnode = ncsize; /* dnlc.h */ nsmbnode_max = (ulong_t)((kmem_maxavail() >> 2) / sizeof (struct smbnode)); if (nsmbnode > nsmbnode_max || (nsmbnode == 0 && ncsize == 0)) { zcmn_err(GLOBAL_ZONEID, CE_NOTE, "setting nsmbnode to max value of %ld", nsmbnode_max); nsmbnode = nsmbnode_max; } smbtablesize = 1 << highbit(nsmbnode / smbhashlen); smbtablemask = smbtablesize - 1; smbtable = kmem_alloc(smbtablesize * sizeof (*smbtable), KM_SLEEP); for (i = 0; i < smbtablesize; i++) { smbtable[i].r_hashf = (smbnode_t *)(&smbtable[i]); smbtable[i].r_hashb = (smbnode_t *)(&smbtable[i]); rw_init(&smbtable[i].r_lock, NULL, RW_DEFAULT, NULL); } smbnode_cache = kmem_cache_create("smbnode_cache", sizeof (smbnode_t), 0, NULL, NULL, smbfs_kmem_reclaim, NULL, NULL, 0); /* * Initialize the various mutexes and reader/writer locks */ mutex_init(&smbfreelist_lock, NULL, MUTEX_DEFAULT, NULL); mutex_init(&smbfs_minor_lock, NULL, MUTEX_DEFAULT, NULL); /* * Assign unique major number for all smbfs mounts */ if ((smbfs_major = getudev()) == -1) { zcmn_err(GLOBAL_ZONEID, CE_WARN, "smbfs: init: can't get unique device number"); smbfs_major = 0; } smbfs_minor = 0; return (0); } /* * free smbfs hash table, etc. * NFS: nfs_subr.c:nfs_subrfini */ void smbfs_subrfini(void) { int i; /* * Deallocate the smbnode hash queues */ kmem_cache_destroy(smbnode_cache); for (i = 0; i < smbtablesize; i++) rw_destroy(&smbtable[i].r_lock); kmem_free(smbtable, smbtablesize * sizeof (*smbtable)); /* * Destroy the various mutexes and reader/writer locks */ mutex_destroy(&smbfreelist_lock); mutex_destroy(&smbfs_minor_lock); } /* rddir_cache ? */ /* * Support functions for smbfs_kmem_reclaim */ static int smbfs_node_reclaim(void) { int freed; smbnode_t *np; vnode_t *vp; freed = 0; mutex_enter(&smbfreelist_lock); while ((np = smbfreelist) != NULL) { smb_rmfree(np); mutex_exit(&smbfreelist_lock); if (np->r_flags & RHASHED) { vp = SMBTOV(np); rw_enter(&np->r_hashq->r_lock, RW_WRITER); mutex_enter(&vp->v_lock); if (vp->v_count > 1) { vp->v_count--; mutex_exit(&vp->v_lock); rw_exit(&np->r_hashq->r_lock); mutex_enter(&smbfreelist_lock); continue; } mutex_exit(&vp->v_lock); smb_rmhash_locked(np); rw_exit(&np->r_hashq->r_lock); } /* * This call to smb_addfree will end up destroying the * smbnode, but in a safe way with the appropriate set * of checks done. */ smb_addfree(np); mutex_enter(&smbfreelist_lock); } mutex_exit(&smbfreelist_lock); return (freed); } /* * Called by kmem_cache_alloc ask us if we could * "Please give back some memory!" * * Todo: dump nodes from the free list? */ /*ARGSUSED*/ void smbfs_kmem_reclaim(void *cdrarg) { (void) smbfs_node_reclaim(); } /* nfs failover stuff */ /* nfs_rw_xxx - see smbfs_rwlock.c */