diff options
Diffstat (limited to 'sys/nfs/nfs_node.c')
| -rw-r--r-- | sys/nfs/nfs_node.c | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/sys/nfs/nfs_node.c b/sys/nfs/nfs_node.c new file mode 100644 index 0000000..89cbdce --- /dev/null +++ b/sys/nfs/nfs_node.c @@ -0,0 +1,390 @@ +/* + * Copyright (c) 1989, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Rick Macklem at The University of Guelph. + * + * 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. + * + * @(#)nfs_node.c 8.6 (Berkeley) 5/22/95 + * $FreeBSD$ + */ + + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/proc.h> +#include <sys/mount.h> +#include <sys/namei.h> +#include <sys/vnode.h> +#include <sys/malloc.h> + +#include <vm/vm_zone.h> + +#include <nfs/rpcv2.h> +#include <nfs/nfsproto.h> +#include <nfs/nfs.h> +#include <nfs/nfsnode.h> +#include <nfs/nfsmount.h> + +static vm_zone_t nfsnode_zone; +static LIST_HEAD(nfsnodehashhead, nfsnode) *nfsnodehashtbl; +static u_long nfsnodehash; + +#define TRUE 1 +#define FALSE 0 + +/* + * Initialize hash links for nfsnodes + * and build nfsnode free list. + */ +void +nfs_nhinit() +{ + nfsnode_zone = zinit("NFSNODE", sizeof(struct nfsnode), 0, 0, 1); + nfsnodehashtbl = hashinit(desiredvnodes, M_NFSHASH, &nfsnodehash); +} + +/* + * Compute an entry in the NFS hash table structure + */ +u_long +nfs_hash(fhp, fhsize) + register nfsfh_t *fhp; + int fhsize; +{ + register u_char *fhpp; + register u_long fhsum; + register int i; + + fhpp = &fhp->fh_bytes[0]; + fhsum = 0; + for (i = 0; i < fhsize; i++) + fhsum += *fhpp++; + return (fhsum); +} + +/* + * Look up a vnode/nfsnode by file handle. + * Callers must check for mount points!! + * In all cases, a pointer to a + * nfsnode structure is returned. + */ +static int nfs_node_hash_lock; + +int +nfs_nget(mntp, fhp, fhsize, npp) + struct mount *mntp; + register nfsfh_t *fhp; + int fhsize; + struct nfsnode **npp; +{ + struct proc *p = curproc; /* XXX */ + struct nfsnode *np, *np2; + struct nfsnodehashhead *nhpp; + register struct vnode *vp; + struct vnode *nvp; + int error; + +retry: + nhpp = NFSNOHASH(nfs_hash(fhp, fhsize)); +loop: + for (np = nhpp->lh_first; np != 0; np = np->n_hash.le_next) { + if (mntp != NFSTOV(np)->v_mount || np->n_fhsize != fhsize || + bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize)) + continue; + vp = NFSTOV(np); + if (vget(vp, LK_EXCLUSIVE, p)) + goto loop; + *npp = np; + return(0); + } + /* + * Obtain a lock to prevent a race condition if the getnewvnode() + * or MALLOC() below happens to block. + */ + if (nfs_node_hash_lock) { + while (nfs_node_hash_lock) { + nfs_node_hash_lock = -1; + tsleep(&nfs_node_hash_lock, PVM, "nfsngt", 0); + } + goto loop; + } + nfs_node_hash_lock = 1; + + /* + * Allocate before getnewvnode since doing so afterward + * might cause a bogus v_data pointer to get dereferenced + * elsewhere if zalloc should block. + */ + np = zalloc(nfsnode_zone); + + error = getnewvnode(VT_NFS, mntp, nfsv2_vnodeop_p, &nvp); + if (error) { + if (nfs_node_hash_lock < 0) + wakeup(&nfs_node_hash_lock); + nfs_node_hash_lock = 0; + *npp = 0; + zfree(nfsnode_zone, np); + return (error); + } + vp = nvp; + bzero((caddr_t)np, sizeof *np); + vp->v_data = np; + np->n_vnode = vp; + /* + * Insert the nfsnode in the hash queue for its new file handle + */ + for (np2 = nhpp->lh_first; np2 != 0; np2 = np2->n_hash.le_next) { + if (mntp != NFSTOV(np2)->v_mount || np2->n_fhsize != fhsize || + bcmp((caddr_t)fhp, (caddr_t)np2->n_fhp, fhsize)) + continue; + vrele(vp); + if (nfs_node_hash_lock < 0) + wakeup(&nfs_node_hash_lock); + nfs_node_hash_lock = 0; + zfree(nfsnode_zone, np); + goto retry; + } + LIST_INSERT_HEAD(nhpp, np, n_hash); + if (fhsize > NFS_SMALLFH) { + MALLOC(np->n_fhp, nfsfh_t *, fhsize, M_NFSBIGFH, M_WAITOK); + } else + np->n_fhp = &np->n_fh; + bcopy((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize); + np->n_fhsize = fhsize; + lockinit(&np->n_rslock, PVFS, "nfrslk", 0, LK_NOPAUSE); + *npp = np; + + if (nfs_node_hash_lock < 0) + wakeup(&nfs_node_hash_lock); + nfs_node_hash_lock = 0; + + /* + * Lock the new nfsnode. + */ + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + + return (0); +} + +int +nfs_inactive(ap) + struct vop_inactive_args /* { + struct vnode *a_vp; + struct proc *a_p; + } */ *ap; +{ + register struct nfsnode *np; + register struct sillyrename *sp; + struct proc *p = curproc; /* XXX */ + + np = VTONFS(ap->a_vp); + if (prtactive && ap->a_vp->v_usecount != 0) + vprint("nfs_inactive: pushing active", ap->a_vp); + if (ap->a_vp->v_type != VDIR) { + sp = np->n_sillyrename; + np->n_sillyrename = (struct sillyrename *)0; + } else + sp = (struct sillyrename *)0; + if (sp) { + /* + * We need a reference to keep the vnode from being + * recycled by getnewvnode while we do the I/O + * associated with discarding the buffers unless we + * are being forcibly unmounted in which case we already + * have our own reference. + */ + if (ap->a_vp->v_usecount > 0) + (void) nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, p, 1); + else if (vget(ap->a_vp, 0, p)) + panic("nfs_inactive: lost vnode"); + else { + (void) nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, p, 1); + vrele(ap->a_vp); + } + /* + * Remove the silly file that was rename'd earlier + */ + nfs_removeit(sp); + crfree(sp->s_cred); + vrele(sp->s_dvp); + FREE((caddr_t)sp, M_NFSREQ); + } + np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT | NQNFSEVICTED | + NQNFSNONCACHE | NQNFSWRITE); + VOP_UNLOCK(ap->a_vp, 0, ap->a_p); + return (0); +} + +/* + * Reclaim an nfsnode so that it can be used for other purposes. + */ +int +nfs_reclaim(ap) + struct vop_reclaim_args /* { + struct vnode *a_vp; + } */ *ap; +{ + register struct vnode *vp = ap->a_vp; + register struct nfsnode *np = VTONFS(vp); + register struct nfsmount *nmp = VFSTONFS(vp->v_mount); + register struct nfsdmap *dp, *dp2; + + if (prtactive && vp->v_usecount != 0) + vprint("nfs_reclaim: pushing active", vp); + + if (np->n_hash.le_prev != NULL) + LIST_REMOVE(np, n_hash); + + /* + * For nqnfs, take it off the timer queue as required. + */ + if ((nmp->nm_flag & NFSMNT_NQNFS) && np->n_timer.cqe_next != 0) { + CIRCLEQ_REMOVE(&nmp->nm_timerhead, np, n_timer); + } + + /* + * Free up any directory cookie structures and + * large file handle structures that might be associated with + * this nfs node. + */ + if (vp->v_type == VDIR) { + dp = np->n_cookies.lh_first; + while (dp) { + dp2 = dp; + dp = dp->ndm_list.le_next; + FREE((caddr_t)dp2, M_NFSDIROFF); + } + } + if (np->n_fhsize > NFS_SMALLFH) { + FREE((caddr_t)np->n_fhp, M_NFSBIGFH); + } + + cache_purge(vp); + zfree(nfsnode_zone, vp->v_data); + vp->v_data = (void *)0; + return (0); +} + +#if 0 +/* + * Lock an nfsnode + */ +int +nfs_lock(ap) + struct vop_lock_args /* { + struct vnode *a_vp; + } */ *ap; +{ + register struct vnode *vp = ap->a_vp; + + /* + * Ugh, another place where interruptible mounts will get hung. + * If you make this sleep interruptible, then you have to fix all + * the VOP_LOCK() calls to expect interruptibility. + */ + while (vp->v_flag & VXLOCK) { + vp->v_flag |= VXWANT; + (void) tsleep((caddr_t)vp, PINOD, "nfslck", 0); + } + if (vp->v_tag == VT_NON) + return (ENOENT); + +#if 0 + /* + * Only lock regular files. If a server crashed while we were + * holding a directory lock, we could easily end up sleeping + * until the server rebooted while holding a lock on the root. + * Locks are only needed for protecting critical sections in + * VMIO at the moment. + * New vnodes will have type VNON but they should be locked + * since they may become VREG. This is checked in loadattrcache + * and unwanted locks are released there. + */ + if (vp->v_type == VREG || vp->v_type == VNON) { + while (np->n_flag & NLOCKED) { + np->n_flag |= NWANTED; + (void) tsleep((caddr_t) np, PINOD, "nfslck2", 0); + /* + * If the vnode has transmuted into a VDIR while we + * were asleep, then skip the lock. + */ + if (vp->v_type != VREG && vp->v_type != VNON) + return (0); + } + np->n_flag |= NLOCKED; + } +#endif + + return (0); +} + +/* + * Unlock an nfsnode + */ +int +nfs_unlock(ap) + struct vop_unlock_args /* { + struct vnode *a_vp; + } */ *ap; +{ +#if 0 + struct vnode* vp = ap->a_vp; + struct nfsnode* np = VTONFS(vp); + + if (vp->v_type == VREG || vp->v_type == VNON) { + if (!(np->n_flag & NLOCKED)) + panic("nfs_unlock: nfsnode not locked"); + np->n_flag &= ~NLOCKED; + if (np->n_flag & NWANTED) { + np->n_flag &= ~NWANTED; + wakeup((caddr_t) np); + } + } +#endif + + return (0); +} + +/* + * Check for a locked nfsnode + */ +int +nfs_islocked(ap) + struct vop_islocked_args /* { + struct vnode *a_vp; + struct proc *a_p; + } */ *ap; +{ + return VTONFS(ap->a_vp)->n_flag & NLOCKED ? 1 : 0; +} +#endif + |
