/* $NetBSD: kernfs_subr.c,v 1.6 2004/05/07 15:20:29 cl Exp $ */ /* * Copyright (c) 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Jan-Simon Pendry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kernfs_subr.c 8.6 (Berkeley) 5/14/95 */ /* * Copyright (c) 1994 Christopher G. Demetriou. All rights reserved. * Copyright (c) 1993 Jan-Simon Pendry * * This code is derived from software contributed to Berkeley by * Jan-Simon Pendry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kernfs_subr.c 8.6 (Berkeley) 5/14/95 */ #include __KERNEL_RCSID(0, "$NetBSD: kernfs_subr.c,v 1.6 2004/05/07 15:20:29 cl Exp $"); #ifdef _KERNEL_OPT #include "opt_ipsec.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #ifdef IPSEC #include #include #include #include #include #include #endif void kernfs_hashins __P((struct kernfs_node *)); void kernfs_hashrem __P((struct kernfs_node *)); struct vnode *kernfs_hashget __P((kfstype, struct mount *, const struct kern_target *, u_int32_t)); static LIST_HEAD(kfs_hashhead, kernfs_node) *kfs_hashtbl; static u_long kfs_ihash; /* size of hash table - 1 */ #define KFSVALUEHASH(v) ((v) & kfs_ihash) static struct lock kfs_hashlock; static struct simplelock kfs_hash_slock; #define ISSET(t, f) ((t) & (f)) /* * allocate a kfsnode/vnode pair. the vnode is * referenced, and locked. * * the kfs_type, kfs_value and mount point uniquely * identify a kfsnode. the mount point is needed * because someone might mount this filesystem * twice. * * all kfsnodes are maintained on a singly-linked * list. new nodes are only allocated when they cannot * be found on this list. entries on the list are * removed when the vfs reclaim entry is called. * * a single lock is kept for the entire list. this is * needed because the getnewvnode() function can block * waiting for a vnode to become free, in which case there * may be more than one process trying to get the same * vnode. this lock is only taken if we are going to * call getnewvnode, since the kernel itself is single-threaded. * * if an entry is found on the list, then call vget() to * take a reference. this is done because there may be * zero references to it and so it needs to removed from * the vnode free list. */ int kernfs_allocvp(mp, vpp, kfs_type, kt, value) struct mount *mp; struct vnode **vpp; kfstype kfs_type; const struct kern_target *kt; u_int32_t value; { struct kernfs_node *kfs = NULL, *kfsp; struct vnode *vp = NULL; int error; long *cookie; do { if ((*vpp = kernfs_hashget(kfs_type, mp, kt, value)) != NULL) return (0); } while (lockmgr(&kfs_hashlock, LK_EXCLUSIVE|LK_SLEEPFAIL, 0)); if (kfs_type == KFSdevice) { /* /kern/rootdev = look for device and obey */ /* /kern/rrootdev = look for device and obey */ dev_t *dp; struct vnode *fvp; #ifdef DIAGNOSTIC if (!kt) panic("kernfs: kt == NULL for KFSdevice"); #endif dp = kt->kt_data; loop: if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp)) { lockmgr(&kfs_hashlock, LK_RELEASE, NULL); return (ENOENT); } vp = fvp; if (vget(fvp, LK_EXCLUSIVE)) goto loop; *vpp = vp; lockmgr(&kfs_hashlock, LK_RELEASE, NULL); return (0); } if ((error = getnewvnode(VT_KERNFS, mp, kernfs_vnodeop_p, &vp)) != 0) { *vpp = NULL; lockmgr(&kfs_hashlock, LK_RELEASE, NULL); return (error); } MALLOC(kfs, void *, sizeof(struct kernfs_node), M_TEMP, M_WAITOK); memset(kfs, 0, sizeof(*kfs)); vp->v_data = kfs; cookie = &(VFSTOKERNFS(mp)->fileno_cookie); again: TAILQ_FOREACH(kfsp, &VFSTOKERNFS(mp)->nodelist, kfs_list) { if (kfsp->kfs_cookie == *cookie) { (*cookie) ++; goto again; } if (TAILQ_NEXT(kfsp, kfs_list)) { if (kfsp->kfs_cookie < *cookie && *cookie < TAILQ_NEXT(kfsp, kfs_list)->kfs_cookie) break; if (kfsp->kfs_cookie + 1 < TAILQ_NEXT(kfsp, kfs_list)->kfs_cookie) { *cookie = kfsp->kfs_cookie + 1; break; } } } kfs->kfs_cookie = *cookie; if (kfsp) TAILQ_INSERT_AFTER(&VFSTOKERNFS(mp)->nodelist, kfsp, kfs, kfs_list); else TAILQ_INSERT_TAIL(&VFSTOKERNFS(mp)->nodelist, kfs, kfs_list); kfs->kfs_type = kfs_type; kfs->kfs_vnode = vp; kfs->kfs_fileno = KERNFS_FILENO(kt, kfs_type, kfs->kfs_cookie); kfs->kfs_value = value; kfs->kfs_kt = kt; kfs->kfs_mode = kt->kt_mode; vp->v_type = kt->kt_vtype; if (kfs_type == KFSkern) vp->v_flag = VROOT; kernfs_hashins(kfs); uvm_vnp_setsize(vp, 0); lockmgr(&kfs_hashlock, LK_RELEASE, NULL); *vpp = vp; return (0); } int kernfs_freevp(vp) struct vnode *vp; { struct kernfs_node *kfs = VTOKERN(vp); kernfs_hashrem(kfs); TAILQ_REMOVE(&VFSTOKERNFS(vp->v_mount)->nodelist, kfs, kfs_list); FREE(vp->v_data, M_TEMP); vp->v_data = 0; return (0); } /* * Initialize kfsnode hash table. */ void kernfs_hashinit() { lockinit(&kfs_hashlock, PINOD, "kfs_hashlock", 0, 0); kfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, &kfs_ihash); simple_lock_init(&kfs_hash_slock); } void kernfs_hashreinit() { struct kernfs_node *pp; struct kfs_hashhead *oldhash, *hash; u_long i, oldmask, mask, val; hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, &mask); simple_lock(&kfs_hash_slock); oldhash = kfs_hashtbl; oldmask = kfs_ihash; kfs_hashtbl = hash; kfs_ihash = mask; for (i = 0; i <= oldmask; i++) { while ((pp = LIST_FIRST(&oldhash[i])) != NULL) { LIST_REMOVE(pp, kfs_hash); val = KFSVALUEHASH(pp->kfs_value); LIST_INSERT_HEAD(&hash[val], pp, kfs_hash); } } simple_unlock(&kfs_hash_slock); hashdone(oldhash, M_UFSMNT); } /* * Free kfsnode hash table. */ void kernfs_hashdone() { hashdone(kfs_hashtbl, M_UFSMNT); } struct vnode * kernfs_hashget(type, mp, kt, value) kfstype type; struct mount *mp; const struct kern_target *kt; u_int32_t value; { struct kfs_hashhead *ppp; struct kernfs_node *pp; struct vnode *vp; loop: simple_lock(&kfs_hash_slock); ppp = &kfs_hashtbl[KFSVALUEHASH(value)]; LIST_FOREACH(pp, ppp, kfs_hash) { vp = KERNFSTOV(pp); if (pp->kfs_type == type && vp->v_mount == mp && pp->kfs_kt == kt && pp->kfs_value == value) { simple_lock(&vp->v_interlock); simple_unlock(&kfs_hash_slock); if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) goto loop; return (vp); } } simple_unlock(&kfs_hash_slock); return (NULL); } /* * Insert the kfsnode into the hash table and lock it. */ void kernfs_hashins(pp) struct kernfs_node *pp; { struct kfs_hashhead *ppp; /* lock the kfsnode, then put it on the appropriate hash list */ lockmgr(&pp->kfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); simple_lock(&kfs_hash_slock); ppp = &kfs_hashtbl[KFSVALUEHASH(pp->kfs_value)]; LIST_INSERT_HEAD(ppp, pp, kfs_hash); simple_unlock(&kfs_hash_slock); } /* * Remove the kfsnode from the hash table. */ void kernfs_hashrem(pp) struct kernfs_node *pp; { simple_lock(&kfs_hash_slock); LIST_REMOVE(pp, kfs_hash); simple_unlock(&kfs_hash_slock); } #ifdef IPSEC void kernfs_revoke_sa(sav) struct secasvar *sav; { struct kernfs_node *kfs, *pnext; struct vnode *vp; struct kfs_hashhead *ppp; struct mbuf *m; ppp = &kfs_hashtbl[KFSVALUEHASH(ntohl(sav->spi))]; for (kfs = LIST_FIRST(ppp); kfs; kfs = pnext) { vp = KERNFSTOV(kfs); pnext = LIST_NEXT(kfs, kfs_hash); if (vp->v_usecount > 0 && kfs->kfs_type == KFSipsecsa && kfs->kfs_value == ntohl(sav->spi)) { m = key_setdumpsa_spi(sav->spi); if (!m) VOP_REVOKE(vp, REVOKEALL); else m_freem(m); break; } } } void kernfs_revoke_sp(sp) struct secpolicy *sp; { struct kernfs_node *kfs, *pnext; struct vnode *vp; struct kfs_hashhead *ppp; ppp = &kfs_hashtbl[KFSVALUEHASH(sp->id)]; for (kfs = LIST_FIRST(ppp); kfs; kfs = pnext) { vp = KERNFSTOV(kfs); pnext = LIST_NEXT(kfs, kfs_hash); if (vp->v_usecount > 0 && kfs->kfs_type == KFSipsecsa && kfs->kfs_value == sp->id) VOP_REVOKE(vp, REVOKEALL); } } #endif