/* $NetBSD: vfs_subr.c,v 1.36 1995/01/09 19:54:28 mycroft Exp $ */ /* * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * 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. * * @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94 */ /* * External virtual filesystem routines */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include enum vtype iftovt_tab[16] = { VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, }; int vttoif_tab[9] = { 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFSOCK, S_IFIFO, S_IFMT, }; int doforce = 1; /* 1 => permit forcible unmounting */ int prtactive = 0; /* 1 => print out reclaim of active vnodes */ /* * Insq/Remq for the vnode usage lists. */ #define bufinsvn(bp, dp) LIST_INSERT_HEAD(dp, bp, b_vnbufs) #define bufremvn(bp) { \ LIST_REMOVE(bp, b_vnbufs); \ (bp)->b_vnbufs.le_next = NOLIST; \ } TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */ struct mntlist mountlist; /* mounted filesystem list */ /* * Initialize the vnode management data structures. */ vntblinit() { TAILQ_INIT(&vnode_free_list); CIRCLEQ_INIT(&mountlist); } /* * Lock a filesystem. * Used to prevent access to it while mounting and unmounting. */ vfs_lock(mp) register struct mount *mp; { while (mp->mnt_flag & MNT_MLOCK) { mp->mnt_flag |= MNT_MWAIT; tsleep((caddr_t)mp, PVFS, "vfslock", 0); } mp->mnt_flag |= MNT_MLOCK; return (0); } /* * Unlock a locked filesystem. * Panic if filesystem is not locked. */ void vfs_unlock(mp) register struct mount *mp; { if ((mp->mnt_flag & MNT_MLOCK) == 0) panic("vfs_unlock: not locked"); mp->mnt_flag &= ~MNT_MLOCK; if (mp->mnt_flag & MNT_MWAIT) { mp->mnt_flag &= ~MNT_MWAIT; wakeup((caddr_t)mp); } } /* * Mark a mount point as busy. * Used to synchronize access and to delay unmounting. */ vfs_busy(mp) register struct mount *mp; { while(mp->mnt_flag & MNT_MPBUSY) { mp->mnt_flag |= MNT_MPWANT; tsleep((caddr_t)&mp->mnt_flag, PVFS, "vfsbusy", 0); } if (mp->mnt_flag & MNT_UNMOUNT) return (1); mp->mnt_flag |= MNT_MPBUSY; return (0); } /* * Free a busy filesystem. * Panic if filesystem is not busy. */ vfs_unbusy(mp) register struct mount *mp; { if ((mp->mnt_flag & MNT_MPBUSY) == 0) panic("vfs_unbusy: not busy"); mp->mnt_flag &= ~MNT_MPBUSY; if (mp->mnt_flag & MNT_MPWANT) { mp->mnt_flag &= ~MNT_MPWANT; wakeup((caddr_t)&mp->mnt_flag); } } /* * Lookup a mount point by filesystem identifier. */ struct mount * getvfs(fsid) fsid_t *fsid; { register struct mount *mp; for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = mp->mnt_list.cqe_next) if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) return (mp); return ((struct mount *)0); } /* * Get a new unique fsid */ void getnewfsid(mp, mtype) struct mount *mp; int mtype; { static u_short xxxfs_mntid; fsid_t tfsid; mp->mnt_stat.f_fsid.val[0] = makedev(nblkdev + 11, 0); /* XXX */ mp->mnt_stat.f_fsid.val[1] = mtype; if (xxxfs_mntid == 0) ++xxxfs_mntid; tfsid.val[0] = makedev((nblkdev + mtype) & 0xff, xxxfs_mntid); tfsid.val[1] = mtype; if (mountlist.cqh_first != (void *)&mountlist) { while (getvfs(&tfsid)) { tfsid.val[0]++; xxxfs_mntid++; } } mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; } /* * Make a 'unique' number from a mount type name. */ long makefstype(type) char *type; { long rv; for (rv = 0; *type; type++) { rv <<= 2; rv ^= *type; } return rv; } /* * Set vnode attributes to VNOVAL */ void vattr_null(vap) register struct vattr *vap; { vap->va_type = VNON; /* XXX These next two used to be one line, but for a GCC bug. */ vap->va_size = VNOVAL; vap->va_bytes = VNOVAL; vap->va_mode = vap->va_nlink = vap->va_uid = vap->va_gid = vap->va_fsid = vap->va_fileid = vap->va_blocksize = vap->va_rdev = vap->va_atime.ts_sec = vap->va_atime.ts_nsec = vap->va_mtime.ts_sec = vap->va_mtime.ts_nsec = vap->va_ctime.ts_sec = vap->va_ctime.ts_nsec = vap->va_flags = vap->va_gen = VNOVAL; vap->va_vaflags = 0; } /* * Routines having to do with the management of the vnode table. */ extern int (**dead_vnodeop_p)(); extern void vclean(); long numvnodes; /* * Return the next vnode from the free list. */ getnewvnode(tag, mp, vops, vpp) enum vtagtype tag; struct mount *mp; int (**vops)(); struct vnode **vpp; { register struct vnode *vp; int s; if ((vnode_free_list.tqh_first == NULL && numvnodes < 2 * desiredvnodes) || numvnodes < desiredvnodes) { vp = (struct vnode *)malloc((u_long)sizeof *vp, M_VNODE, M_WAITOK); bzero((char *)vp, sizeof *vp); numvnodes++; } else { if ((vp = vnode_free_list.tqh_first) == NULL) { tablefull("vnode"); *vpp = 0; return (ENFILE); } if (vp->v_usecount) panic("free vnode isn't"); TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); /* see comment on why 0xdeadb is set at end of vgone (below) */ vp->v_freelist.tqe_prev = (struct vnode **)0xdeadb; vp->v_lease = NULL; if (vp->v_type != VBAD) vgone(vp); #ifdef DIAGNOSTIC if (vp->v_data) panic("cleaned vnode isn't"); s = splbio(); if (vp->v_numoutput) panic("Clean vnode has pending I/O's"); splx(s); #endif vp->v_flag = 0; vp->v_lastr = 0; vp->v_ralen = 0; vp->v_maxra = 0; vp->v_lastw = 0; vp->v_lasta = 0; vp->v_cstart = 0; vp->v_clen = 0; vp->v_socket = 0; } vp->v_type = VNON; cache_purge(vp); vp->v_tag = tag; vp->v_op = vops; insmntque(vp, mp); *vpp = vp; vp->v_usecount = 1; vp->v_data = 0; return (0); } /* * Move a vnode from one mount queue to another. */ insmntque(vp, mp) register struct vnode *vp; register struct mount *mp; { /* * Delete from old mount point vnode list, if on one. */ if (vp->v_mount != NULL) LIST_REMOVE(vp, v_mntvnodes); /* * Insert into list of vnodes for the new mount point, if available. */ if ((vp->v_mount = mp) == NULL) return; LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); } /* * Update outstanding I/O count and do wakeup if requested. */ vwakeup(bp) register struct buf *bp; { register struct vnode *vp; bp->b_flags &= ~B_WRITEINPROG; if (vp = bp->b_vp) { if (--vp->v_numoutput < 0) panic("vwakeup: neg numoutput"); if ((vp->v_flag & VBWAIT) && vp->v_numoutput <= 0) { vp->v_flag &= ~VBWAIT; wakeup((caddr_t)&vp->v_numoutput); } } } /* * Flush out and invalidate all buffers associated with a vnode. * Called with the underlying object locked. */ int vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) register struct vnode *vp; int flags; struct ucred *cred; struct proc *p; int slpflag, slptimeo; { register struct buf *bp; struct buf *nbp, *blist; int s, error; if (flags & V_SAVE) { if (error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) return (error); if (vp->v_dirtyblkhd.lh_first != NULL) panic("vinvalbuf: dirty bufs"); } for (;;) { if ((blist = vp->v_cleanblkhd.lh_first) && flags & V_SAVEMETA) while (blist && blist->b_lblkno < 0) blist = blist->b_vnbufs.le_next; if (!blist && (blist = vp->v_dirtyblkhd.lh_first) && (flags & V_SAVEMETA)) while (blist && blist->b_lblkno < 0) blist = blist->b_vnbufs.le_next; if (!blist) break; for (bp = blist; bp; bp = nbp) { nbp = bp->b_vnbufs.le_next; if (flags & V_SAVEMETA && bp->b_lblkno < 0) continue; s = splbio(); if (bp->b_flags & B_BUSY) { bp->b_flags |= B_WANTED; error = tsleep((caddr_t)bp, slpflag | (PRIBIO + 1), "vinvalbuf", slptimeo); splx(s); if (error) return (error); break; } bremfree(bp); bp->b_flags |= B_BUSY; splx(s); /* * XXX Since there are no node locks for NFS, I believe * there is a slight chance that a delayed write will * occur while sleeping just above, so check for it. */ if ((bp->b_flags & B_DELWRI) && (flags & V_SAVE)) { (void) VOP_BWRITE(bp); break; } bp->b_flags |= B_INVAL; brelse(bp); } } if (!(flags & V_SAVEMETA) && (vp->v_dirtyblkhd.lh_first || vp->v_cleanblkhd.lh_first)) panic("vinvalbuf: flush failed"); return (0); } void vflushbuf(vp, sync) register struct vnode *vp; int sync; { register struct buf *bp, *nbp; int s; loop: s = splbio(); for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) { nbp = bp->b_vnbufs.le_next; if ((bp->b_flags & B_BUSY)) continue; if ((bp->b_flags & B_DELWRI) == 0) panic("vflushbuf: not dirty"); bremfree(bp); bp->b_flags |= B_BUSY; splx(s); /* * Wait for I/O associated with indirect blocks to complete, * since there is no way to quickly wait for them below. */ if (bp->b_vp == vp || sync == 0) (void) bawrite(bp); else (void) bwrite(bp); goto loop; } if (sync == 0) { splx(s); return; } while (vp->v_numoutput) { vp->v_flag |= VBWAIT; tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "vflushbuf", 0); } splx(s); if (vp->v_dirtyblkhd.lh_first != NULL) { vprint("vflushbuf: dirty", vp); goto loop; } } /* * Associate a buffer with a vnode. */ bgetvp(vp, bp) register struct vnode *vp; register struct buf *bp; { if (bp->b_vp) panic("bgetvp: not free"); VHOLD(vp); bp->b_vp = vp; if (vp->v_type == VBLK || vp->v_type == VCHR) bp->b_dev = vp->v_rdev; else bp->b_dev = NODEV; /* * Insert onto list for new vnode. */ bufinsvn(bp, &vp->v_cleanblkhd); } /* * Disassociate a buffer from a vnode. */ brelvp(bp) register struct buf *bp; { struct vnode *vp; if (bp->b_vp == (struct vnode *) 0) panic("brelvp: NULL"); /* * Delete from old vnode list, if on one. */ if (bp->b_vnbufs.le_next != NOLIST) bufremvn(bp); vp = bp->b_vp; bp->b_vp = (struct vnode *) 0; HOLDRELE(vp); } /* * Reassign a buffer from one vnode to another. * Used to assign file specific control information * (indirect blocks) to the vnode to which they belong. */ reassignbuf(bp, newvp) register struct buf *bp; register struct vnode *newvp; { register struct buflists *listheadp; if (newvp == NULL) { printf("reassignbuf: NULL"); return; } /* * Delete from old vnode list, if on one. */ if (bp->b_vnbufs.le_next != NOLIST) bufremvn(bp); /* * If dirty, put on list of dirty buffers; * otherwise insert onto list of clean buffers. */ if (bp->b_flags & B_DELWRI) listheadp = &newvp->v_dirtyblkhd; else listheadp = &newvp->v_cleanblkhd; bufinsvn(bp, listheadp); } /* * Create a vnode for a block device. * Used for root filesystem, argdev, and swap areas. * Also used for memory file system special devices. */ bdevvp(dev, vpp) dev_t dev; struct vnode **vpp; { return (getdevvp(dev, vpp, VBLK)); } /* * Create a vnode for a character device. * Used for kernfs and some console handling. */ cdevvp(dev, vpp) dev_t dev; struct vnode **vpp; { return (getdevvp(dev, vpp, VCHR)); } /* * Create a vnode for a device. * Used by bdevvp (block device) for root file system etc., * and by cdevvp (character device) for console and kernfs. */ getdevvp(dev, vpp, type) dev_t dev; struct vnode **vpp; enum vtype type; { register struct vnode *vp; struct vnode *nvp; int error; if (dev == NODEV) return (0); error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp); if (error) { *vpp = NULLVP; return (error); } vp = nvp; vp->v_type = type; if (nvp = checkalias(vp, dev, (struct mount *)0)) { vput(vp); vp = nvp; } *vpp = vp; return (0); } /* * Check to see if the new vnode represents a special device * for which we already have a vnode (either because of * bdevvp() or because of a different vnode representing * the same block device). If such an alias exists, deallocate * the existing contents and return the aliased vnode. The * caller is responsible for filling it with its new contents. */ struct vnode * checkalias(nvp, nvp_rdev, mp) register struct vnode *nvp; dev_t nvp_rdev; struct mount *mp; { register struct vnode *vp; struct vnode **vpp; if (nvp->v_type != VBLK && nvp->v_type != VCHR) return (NULLVP); vpp = &speclisth[SPECHASH(nvp_rdev)]; loop: for (vp = *vpp; vp; vp = vp->v_specnext) { if (nvp_rdev != vp->v_rdev || nvp->v_type != vp->v_type) continue; /* * Alias, but not in use, so flush it out. */ if (vp->v_usecount == 0) { vgone(vp); goto loop; } if (vget(vp, 1)) goto loop; break; } if (vp == NULL || vp->v_tag != VT_NON || vp->v_type != VBLK) { MALLOC(nvp->v_specinfo, struct specinfo *, sizeof(struct specinfo), M_VNODE, M_WAITOK); nvp->v_rdev = nvp_rdev; nvp->v_hashchain = vpp; nvp->v_specnext = *vpp; nvp->v_specflags = 0; *vpp = nvp; if (vp != NULL) { nvp->v_flag |= VALIASED; vp->v_flag |= VALIASED; vput(vp); } return (NULLVP); } VOP_UNLOCK(vp); vclean(vp, 0); vp->v_op = nvp->v_op; vp->v_tag = nvp->v_tag; nvp->v_type = VNON; insmntque(vp, mp); return (vp); } /* * Grab a particular vnode from the free list, increment its * reference count and lock it. The vnode lock bit is set the * vnode is being eliminated in vgone. The process is awakened * when the transition is completed, and an error returned to * indicate that the vnode is no longer usable (possibly having * been changed to a new file system type). */ int vget(vp, lockflag) register struct vnode *vp; int lockflag; { /* * If the vnode is in the process of being cleaned out for * another use, we wait for the cleaning to finish and then * return failure. Cleaning is determined either by checking * that the VXLOCK flag is set, or that the use count is * zero with the back pointer set to show that it has been * removed from the free list by getnewvnode. The VXLOCK * flag may not have been set yet because vclean is blocked in * the VOP_LOCK call waiting for the VOP_INACTIVE to complete. */ if ((vp->v_flag & VXLOCK) || (vp->v_usecount == 0 && vp->v_freelist.tqe_prev == (struct vnode **)0xdeadb)) { vp->v_flag |= VXWANT; tsleep((caddr_t)vp, PINOD, "vget", 0); return (1); } if (vp->v_usecount == 0) TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); vp->v_usecount++; if (lockflag) VOP_LOCK(vp); return (0); } /* * Vnode reference, just increment the count */ void vref(vp) struct vnode *vp; { if (vp->v_usecount <= 0) panic("vref used where vget required"); vp->v_usecount++; } /* * vput(), just unlock and vrele() */ void vput(vp) register struct vnode *vp; { VOP_UNLOCK(vp); vrele(vp); } /* * Vnode release. * If count drops to zero, call inactive routine and return to freelist. */ void vrele(vp) register struct vnode *vp; { #ifdef DIAGNOSTIC if (vp == NULL) panic("vrele: null vp"); #endif vp->v_usecount--; if (vp->v_usecount > 0) return; #ifdef DIAGNOSTIC if (vp->v_usecount != 0 || vp->v_writecount != 0) { vprint("vrele: bad ref count", vp); panic("vrele: ref cnt"); } #endif /* * insert at tail of LRU list */ TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); VOP_INACTIVE(vp); } /* * Page or buffer structure gets a reference. */ void vhold(vp) register struct vnode *vp; { vp->v_holdcnt++; } /* * Page or buffer structure frees a reference. */ void holdrele(vp) register struct vnode *vp; { if (vp->v_holdcnt <= 0) panic("holdrele: holdcnt"); vp->v_holdcnt--; } /* * Remove any vnodes in the vnode table belonging to mount point mp. * * If MNT_NOFORCE is specified, there should not be any active ones, * return error if any are found (nb: this is a user error, not a * system error). If MNT_FORCE is specified, detach any active vnodes * that are found. */ #ifdef DEBUG int busyprt = 0; /* print out busy vnodes */ struct ctldebug debug1 = { "busyprt", &busyprt }; #endif vflush(mp, skipvp, flags) struct mount *mp; struct vnode *skipvp; int flags; { register struct vnode *vp, *nvp; int busy = 0; if ((mp->mnt_flag & MNT_MPBUSY) == 0) panic("vflush: not busy"); loop: for (vp = mp->mnt_vnodelist.lh_first; vp; vp = nvp) { if (vp->v_mount != mp) goto loop; nvp = vp->v_mntvnodes.le_next; /* * Skip over a selected vnode. */ if (vp == skipvp) continue; /* * Skip over a vnodes marked VSYSTEM. */ if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) continue; /* * If WRITECLOSE is set, only flush out regular file * vnodes open for writing. */ if ((flags & WRITECLOSE) && (vp->v_writecount == 0 || vp->v_type != VREG)) continue; /* * With v_usecount == 0, all we need to do is clear * out the vnode data structures and we are done. */ if (vp->v_usecount == 0) { vgone(vp); continue; } /* * If FORCECLOSE is set, forcibly close the vnode. * For block or character devices, revert to an * anonymous device. For all other files, just kill them. */ if (flags & FORCECLOSE) { if (vp->v_type != VBLK && vp->v_type != VCHR) { vgone(vp); } else { vclean(vp, 0); vp->v_op = spec_vnodeop_p; insmntque(vp, (struct mount *)0); } continue; } #ifdef DEBUG if (busyprt) vprint("vflush: busy vnode", vp); #endif busy++; } if (busy) return (EBUSY); return (0); } /* * Disassociate the underlying file system from a vnode. */ void vclean(vp, flags) register struct vnode *vp; int flags; { int active; /* * Check to see if the vnode is in use. * If so we have to reference it before we clean it out * so that its count cannot fall to zero and generate a * race against ourselves to recycle it. */ if (active = vp->v_usecount) VREF(vp); /* * Even if the count is zero, the VOP_INACTIVE routine may still * have the object locked while it cleans it out. The VOP_LOCK * ensures that the VOP_INACTIVE routine is done with its work. * For active vnodes, it ensures that no other activity can * occur while the underlying object is being cleaned out. */ VOP_LOCK(vp); /* * Prevent the vnode from being recycled or * brought into use while we clean it out. */ if (vp->v_flag & VXLOCK) panic("vclean: deadlock"); vp->v_flag |= VXLOCK; /* * Clean out any buffers associated with the vnode. */ if (flags & DOCLOSE) vinvalbuf(vp, V_SAVE, NOCRED, NULL, 0, 0); /* * Any other processes trying to obtain this lock must first * wait for VXLOCK to clear, then call the new lock operation. */ VOP_UNLOCK(vp); /* * If purging an active vnode, it must be closed and * deactivated before being reclaimed. */ if (active) { if (flags & DOCLOSE) VOP_CLOSE(vp, IO_NDELAY, NOCRED, NULL); VOP_INACTIVE(vp); } /* * Reclaim the vnode. */ if (VOP_RECLAIM(vp)) panic("vclean: cannot reclaim"); if (active) vrele(vp); /* * Done with purge, notify sleepers of the grim news. */ vp->v_op = dead_vnodeop_p; vp->v_tag = VT_NON; vp->v_flag &= ~VXLOCK; if (vp->v_flag & VXWANT) { vp->v_flag &= ~VXWANT; wakeup((caddr_t)vp); } } /* * Eliminate all activity associated with the requested vnode * and with all vnodes aliased to the requested vnode. */ void vgoneall(vp) register struct vnode *vp; { register struct vnode *vq; if (vp->v_flag & VALIASED) { /* * If a vgone (or vclean) is already in progress, * wait until it is done and return. */ if (vp->v_flag & VXLOCK) { vp->v_flag |= VXWANT; tsleep((caddr_t)vp, PINOD, "vgoneall", 0); return; } /* * Ensure that vp will not be vgone'd while we * are eliminating its aliases. */ vp->v_flag |= VXLOCK; while (vp->v_flag & VALIASED) { for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type || vp == vq) continue; vgone(vq); break; } } /* * Remove the lock so that vgone below will * really eliminate the vnode after which time * vgone will awaken any sleepers. */ vp->v_flag &= ~VXLOCK; } vgone(vp); } /* * Eliminate all activity associated with a vnode * in preparation for reuse. */ void vgone(vp) register struct vnode *vp; { register struct vnode *vq; struct vnode *vx; /* * If a vgone (or vclean) is already in progress, * wait until it is done and return. */ if (vp->v_flag & VXLOCK) { vp->v_flag |= VXWANT; tsleep((caddr_t)vp, PINOD, "vgone", 0); return; } /* * Clean out the filesystem specific data. */ vclean(vp, DOCLOSE); /* * Delete from old mount point vnode list, if on one. */ if (vp->v_mount != NULL) { LIST_REMOVE(vp, v_mntvnodes); vp->v_mount = NULL; } /* * If special device, remove it from special device alias list. */ if (vp->v_type == VBLK || vp->v_type == VCHR) { if (*vp->v_hashchain == vp) { *vp->v_hashchain = vp->v_specnext; } else { for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { if (vq->v_specnext != vp) continue; vq->v_specnext = vp->v_specnext; break; } if (vq == NULL) panic("missing bdev"); } if (vp->v_flag & VALIASED) { vx = NULL; for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) continue; if (vx) break; vx = vq; } if (vx == NULL) panic("missing alias"); if (vq == NULL) vx->v_flag &= ~VALIASED; vp->v_flag &= ~VALIASED; } FREE(vp->v_specinfo, M_VNODE); vp->v_specinfo = NULL; } /* * If it is on the freelist and not already at the head, * move it to the head of the list. The test of the back * pointer and the reference count of zero is because * it will be removed from the free list by getnewvnode, * but will not have its reference count incremented until * after calling vgone. If the reference count were * incremented first, vgone would (incorrectly) try to * close the previous instance of the underlying object. * So, the back pointer is explicitly set to `0xdeadb' in * getnewvnode after removing it from the freelist to ensure * that we do not try to move it here. */ if (vp->v_usecount == 0 && vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb && vnode_free_list.tqh_first != vp) { TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); } vp->v_type = VBAD; } /* * Lookup a vnode by device number. */ vfinddev(dev, type, vpp) dev_t dev; enum vtype type; struct vnode **vpp; { register struct vnode *vp; for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) { if (dev != vp->v_rdev || type != vp->v_type) continue; *vpp = vp; return (1); } return (0); } /* * Calculate the total number of references to a special device. */ int vcount(vp) register struct vnode *vp; { register struct vnode *vq, *vnext; int count; loop: if ((vp->v_flag & VALIASED) == 0) return (vp->v_usecount); for (count = 0, vq = *vp->v_hashchain; vq; vq = vnext) { vnext = vq->v_specnext; if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) continue; /* * Alias, but not in use, so flush it out. */ if (vq->v_usecount == 0 && vq != vp) { vgone(vq); goto loop; } count += vq->v_usecount; } return (count); } /* * Print out a description of a vnode. */ static char *typename[] = { "VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD" }; void vprint(label, vp) char *label; register struct vnode *vp; { char buf[64]; if (label != NULL) printf("%s: ", label); printf("type %s, usecount %d, writecount %d, refcount %d,", typename[vp->v_type], vp->v_usecount, vp->v_writecount, vp->v_holdcnt); buf[0] = '\0'; if (vp->v_flag & VROOT) strcat(buf, "|VROOT"); if (vp->v_flag & VTEXT) strcat(buf, "|VTEXT"); if (vp->v_flag & VSYSTEM) strcat(buf, "|VSYSTEM"); if (vp->v_flag & VXLOCK) strcat(buf, "|VXLOCK"); if (vp->v_flag & VXWANT) strcat(buf, "|VXWANT"); if (vp->v_flag & VBWAIT) strcat(buf, "|VBWAIT"); if (vp->v_flag & VALIASED) strcat(buf, "|VALIASED"); if (buf[0] != '\0') printf(" flags (%s)", &buf[1]); if (vp->v_data == NULL) { printf("\n"); } else { printf("\n\t"); VOP_PRINT(vp); } } #ifdef DEBUG /* * List all of the locked vnodes in the system. * Called when debugging the kernel. */ printlockedvnodes() { register struct mount *mp; register struct vnode *vp; printf("Locked vnodes\n"); for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = mp->mnt_list.cqe_next) { for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = vp->v_mntvnodes.le_next) if (VOP_ISLOCKED(vp)) vprint((char *)0, vp); } } #endif int kinfo_vdebug = 1; int kinfo_vgetfailed; #define KINFO_VNODESLOP 10 /* * Dump vnode list (via sysctl). * Copyout address of vnode followed by vnode. */ /* ARGSUSED */ sysctl_vnode(where, sizep) char *where; size_t *sizep; { register struct mount *mp, *nmp; struct vnode *vp; register char *bp = where, *savebp; char *ewhere; int error; #define VPTRSZ sizeof (struct vnode *) #define VNODESZ sizeof (struct vnode) if (where == NULL) { *sizep = (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ); return (0); } ewhere = where + *sizep; for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { nmp = mp->mnt_list.cqe_next; if (vfs_busy(mp)) continue; savebp = bp; again: for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = vp->v_mntvnodes.le_next) { /* * Check that the vp is still associated with * this filesystem. RACE: could have been * recycled onto the same filesystem. */ if (vp->v_mount != mp) { if (kinfo_vdebug) printf("kinfo: vp changed\n"); bp = savebp; goto again; } if (bp + VPTRSZ + VNODESZ > ewhere) { *sizep = bp - where; return (ENOMEM); } if ((error = copyout((caddr_t)&vp, bp, VPTRSZ)) || (error = copyout((caddr_t)vp, bp + VPTRSZ, VNODESZ))) return (error); bp += VPTRSZ + VNODESZ; } vfs_unbusy(mp); } *sizep = bp - where; return (0); } /* * Check to see if a filesystem is mounted on a block device. */ int vfs_mountedon(vp) register struct vnode *vp; { register struct vnode *vq; if (vp->v_specflags & SI_MOUNTEDON) return (EBUSY); if (vp->v_flag & VALIASED) { for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) continue; if (vq->v_specflags & SI_MOUNTEDON) return (EBUSY); } } return (0); } /* * Build hash lists of net addresses and hang them off the mount point. * Called by ufs_mount() to set up the lists of export addresses. */ static int vfs_hang_addrlist(mp, nep, argp) struct mount *mp; struct netexport *nep; struct export_args *argp; { register struct netcred *np; register struct radix_node_head *rnh; register int i; struct radix_node *rn; struct sockaddr *saddr, *smask = 0; struct domain *dom; int error; if (argp->ex_addrlen == 0) { if (mp->mnt_flag & MNT_DEFEXPORTED) return (EPERM); np = &nep->ne_defexported; np->netc_exflags = argp->ex_flags; np->netc_anon = argp->ex_anon; np->netc_anon.cr_ref = 1; mp->mnt_flag |= MNT_DEFEXPORTED; return (0); } i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; np = (struct netcred *)malloc(i, M_NETADDR, M_WAITOK); bzero((caddr_t)np, i); saddr = (struct sockaddr *)(np + 1); if (error = copyin(argp->ex_addr, (caddr_t)saddr, argp->ex_addrlen)) goto out; if (saddr->sa_len > argp->ex_addrlen) saddr->sa_len = argp->ex_addrlen; if (argp->ex_masklen) { smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen); error = copyin(argp->ex_addr, (caddr_t)smask, argp->ex_masklen); if (error) goto out; if (smask->sa_len > argp->ex_masklen) smask->sa_len = argp->ex_masklen; } i = saddr->sa_family; if ((rnh = nep->ne_rtable[i]) == 0) { /* * Seems silly to initialize every AF when most are not * used, do so on demand here */ for (dom = domains; dom; dom = dom->dom_next) if (dom->dom_family == i && dom->dom_rtattach) { dom->dom_rtattach((void **)&nep->ne_rtable[i], dom->dom_rtoffset); break; } if ((rnh = nep->ne_rtable[i]) == 0) { error = ENOBUFS; goto out; } } rn = (*rnh->rnh_addaddr)((caddr_t)saddr, (caddr_t)smask, rnh, np->netc_rnodes); if (rn == 0 || np != (struct netcred *)rn) { /* already exists */ error = EPERM; goto out; } np->netc_exflags = argp->ex_flags; np->netc_anon = argp->ex_anon; np->netc_anon.cr_ref = 1; return (0); out: free(np, M_NETADDR); return (error); } /* ARGSUSED */ static int vfs_free_netcred(rn, w) struct radix_node *rn; caddr_t w; { register struct radix_node_head *rnh = (struct radix_node_head *)w; (*rnh->rnh_deladdr)(rn->rn_key, rn->rn_mask, rnh); free((caddr_t)rn, M_NETADDR); return (0); } /* * Free the net address hash lists that are hanging off the mount points. */ static void vfs_free_addrlist(nep) struct netexport *nep; { register int i; register struct radix_node_head *rnh; for (i = 0; i <= AF_MAX; i++) if (rnh = nep->ne_rtable[i]) { (*rnh->rnh_walktree)(rnh, vfs_free_netcred, (caddr_t)rnh); free((caddr_t)rnh, M_RTABLE); nep->ne_rtable[i] = 0; } } int vfs_export(mp, nep, argp) struct mount *mp; struct netexport *nep; struct export_args *argp; { int error; if (argp->ex_flags & MNT_DELEXPORT) { vfs_free_addrlist(nep); mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); } if (argp->ex_flags & MNT_EXPORTED) { if (error = vfs_hang_addrlist(mp, nep, argp)) return (error); mp->mnt_flag |= MNT_EXPORTED; } return (0); } struct netcred * vfs_export_lookup(mp, nep, nam) register struct mount *mp; struct netexport *nep; struct mbuf *nam; { register struct netcred *np; register struct radix_node_head *rnh; struct sockaddr *saddr; np = NULL; if (mp->mnt_flag & MNT_EXPORTED) { /* * Lookup in the export list first. */ if (nam != NULL) { saddr = mtod(nam, struct sockaddr *); rnh = nep->ne_rtable[saddr->sa_family]; if (rnh != NULL) { np = (struct netcred *) (*rnh->rnh_matchaddr)((caddr_t)saddr, rnh); if (np && np->netc_rnodes->rn_flags & RNF_ROOT) np = NULL; } } /* * If no address match, use the default if it exists. */ if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) np = &nep->ne_defexported; } return (np); } /* * Do the usual access checking. * file_mode, uid and gid are from the vnode in question, * while acc_mode and cred are from the VOP_ACCESS parameter list */ vaccess(file_mode, uid, gid, acc_mode, cred) mode_t file_mode; uid_t uid; gid_t gid; mode_t acc_mode; struct ucred *cred; { mode_t mask; int i; register gid_t *gp; /* User id 0 always gets access. */ if (cred->cr_uid == 0) return 0; mask = 0; /* Otherwise, check the owner. */ if (cred->cr_uid == uid) { if (acc_mode & VEXEC) mask |= S_IXUSR; if (acc_mode & VREAD) mask |= S_IRUSR; if (acc_mode & VWRITE) mask |= S_IWUSR; return (file_mode & mask) == mask ? 0 : EACCES; } /* Otherwise, check the groups. */ if (groupmember(gid, cred)) { if (acc_mode & VEXEC) mask |= S_IXGRP; if (acc_mode & VREAD) mask |= S_IRGRP; if (acc_mode & VWRITE) mask |= S_IWGRP; return (file_mode & mask) == mask ? 0 : EACCES; } /* Otherwise, check everyone else. */ if (acc_mode & VEXEC) mask |= S_IXOTH; if (acc_mode & VREAD) mask |= S_IROTH; if (acc_mode & VWRITE) mask |= S_IWOTH; return (file_mode & mask) == mask ? 0 : EACCES; } /* * Unmount all file systems. * We traverse the list in reverse order under the assumption that doing so * will avoid needing to worry about dependencies. */ void vfs_unmountall() { register struct mount *mp, *nmp; for (mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) { nmp = mp->mnt_list.cqe_prev; (void) dounmount(mp, MNT_FORCE, &proc0); } }