/* * Copyright (c) 1989, 1990, 1993, 1994 * The Regents of the University of California. All rights reserved. * * 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. * * @(#)mfs_vfsops.c 8.11 (Berkeley) 6/19/95 * $FreeBSD$ */ #include "opt_mfs.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include MALLOC_DEFINE(M_MFSNODE, "MFS node", "MFS vnode private part"); #ifdef MFS_ROOT static caddr_t mfs_rootbase; /* address of mini-root in kernel virtual memory */ static u_long mfs_rootsize; /* size of mini-root in bytes */ #endif static int mfs_minor; /* used for building internal dev_t */ extern vop_t **mfs_vnodeop_p; static int mfs_mount __P((struct mount *mp, char *path, caddr_t data, struct nameidata *ndp, struct proc *p)); static int mfs_start __P((struct mount *mp, int flags, struct proc *p)); static int mfs_statfs __P((struct mount *mp, struct statfs *sbp, struct proc *p)); static int mfs_init __P((struct vfsconf *)); static void mfs_takeroot __P((void *)); static struct cdevsw mfs_cdevsw = { /* open */ noopen, /* close */ noclose, /* read */ physread, /* write */ physwrite, /* ioctl */ noioctl, /* poll */ nopoll, /* mmap */ nommap, /* strategy */ nostrategy, /* name */ "MFS", /* maj */ 253, /* dump */ nodump, /* psize */ nopsize, /* flags */ D_DISK, /* bmaj */ 253, }; /* * mfs vfs operations. */ static struct vfsops mfs_vfsops = { mfs_mount, mfs_start, ffs_unmount, ufs_root, ufs_quotactl, mfs_statfs, ffs_sync, ffs_vget, ffs_fhtovp, ufs_check_export, ffs_vptofh, mfs_init, }; VFS_SET(mfs_vfsops, mfs, 0); #ifdef MFS_ROOT #ifdef MFS_ROOT_SIZE /* Image was already written into mfs_root */ static u_char mfs_root[MFS_ROOT_SIZE*1024] = "MFS Filesystem goes here"; static u_char end_mfs_root[] __unused = "MFS Filesystem had better STOP here"; #endif u_char * mfs_getimage(void) { #ifdef MFS_ROOT_SIZE /* Get it from compiled-in code */ return mfs_root; #else caddr_t p; vm_offset_t *q; p = preload_search_by_type("mfs_root"); if (!p) return NULL; q = (vm_offset_t *)preload_search_info(p, MODINFO_ADDR); if (!q) return NULL; return (u_char *)*q; #endif } #endif /* MFS_ROOT */ /* * mfs_mount * * Called when mounting local physical media * * PARAMETERS: * mountroot * mp mount point structure * path NULL (flag for root mount!!!) * data * ndp * p process (user credentials check [statfs]) * * mount * mp mount point structure * path path to mount point * data pointer to argument struct in user space * ndp mount point namei() return (used for * credentials on reload), reused to look * up block device. * p process (user credentials check) * * RETURNS: 0 Success * !0 error number (errno.h) * * LOCK STATE: * * ENTRY * mount point is locked * EXIT * mount point is locked * * NOTES: * A NULL path can be used for a flag since the mount * system call will fail with EFAULT in copyinstr in * namei() if it is a genuine NULL from the user. */ /* ARGSUSED */ static int mfs_mount(mp, path, data, ndp, p) register struct mount *mp; char *path; caddr_t data; struct nameidata *ndp; struct proc *p; { struct vnode *devvp; struct mfs_args args; struct ufsmount *ump; struct fs *fs; #ifdef MFS_ROOT u_char *base; #endif struct mfsnode *mfsp; size_t size; int flags, err; dev_t dev; /* * Use NULL path to flag a root mount */ if( path == NULL) { /* *** * Mounting root file system *** */ #ifdef MFS_ROOT /* Get it from preload area */ base = mfs_getimage(); if (!base) panic("No mfs_root image loaded; can't continue!"); fs = (struct fs *)(base + SBOFF); /* check for valid super block */ if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE || fs->fs_bsize < sizeof(struct fs)) { panic("MFS image is invalid!!"); } mfs_rootbase = base; mfs_rootsize = fs->fs_fsize * fs->fs_size; /* remake rootdev, since vfs_mountroot will have it wrong */ rootdev = make_dev(&mfs_cdevsw, mfs_minor, 0, 0, 0, "MFS%d", mfs_minor); rootdev->si_bsize_phys = DEV_BSIZE; rootdev->si_iosize_max = DFLTPHYS; mfs_minor++; if ((err = bdevvp(rootdev, &rootvp))) { printf("mfs_mount: can't find rootvp\n"); return (err); } /* * FS specific handling */ MALLOC(mfsp, struct mfsnode *, sizeof *mfsp, M_MFSNODE, M_WAITOK); rootvp->v_data = mfsp; rootvp->v_op = mfs_vnodeop_p; rootvp->v_tag = VT_MFS; mfsp->mfs_baseoff = mfs_rootbase; mfsp->mfs_size = mfs_rootsize; mfsp->mfs_vnode = rootvp; mfsp->mfs_pid = p->p_pid; mfsp->mfs_active = 1; bufq_init(&mfsp->buf_queue); /* MFS wants to be read/write */ mp->mnt_flag &= ~MNT_RDONLY; /* * Attempt mount */ if( (err = ffs_mountfs(rootvp, mp, p, M_MFSNODE)) != 0 ) { /* fs specific cleanup (if any)*/ rootvp->v_data = NULL; FREE(mfsp, M_MFSNODE); goto error_1; } goto dostatfs; /* success*/ #else /* !MFS_ROOT */ /* you loose */ panic("mfs_mount: mount MFS as root: not configured!"); #endif /* MFS_ROOT */ } /* *** * Mounting non-root file system or updating a file system *** */ /* copy in user arguments*/ if ((err = copyin(data, (caddr_t)&args, sizeof (struct mfs_args))) != 0) goto error_1; /* * If updating, check whether changing from read-only to * read/write; if there is no device name, that's all we do. */ if (mp->mnt_flag & MNT_UPDATE) { /* ******************** * UPDATE ******************** */ ump = VFSTOUFS(mp); fs = ump->um_fs; if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) { flags = WRITECLOSE; if (mp->mnt_flag & MNT_FORCE) flags |= FORCECLOSE; err = ffs_flushfiles(mp, flags, p); if (err) goto error_1; } if (fs->fs_ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) fs->fs_ronly = 0; /* if not updating name...*/ if (args.fspec == 0) { /* * Process export requests. Jumping to "success" * will return the vfs_export() error code. */ err = vfs_export(mp, &ump->um_export, &args.export); goto success; } /* XXX MFS does not support name updating*/ goto success; } /* * Do the MALLOC before the getnewvnode since doing so afterward * might cause a bogus v_data pointer to get dereferenced * elsewhere if MALLOC should block. */ MALLOC(mfsp, struct mfsnode *, sizeof *mfsp, M_MFSNODE, M_WAITOK); err = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp); if (err) { FREE(mfsp, M_MFSNODE); goto error_1; } devvp->v_type = VBLK; dev = make_dev(&mfs_cdevsw, mfs_minor, 0, 0, 0, "MFS%d", mfs_minor); /* It is not clear that these will get initialized otherwise */ dev->si_bsize_phys = DEV_BSIZE; dev->si_iosize_max = DFLTPHYS; addaliasu(devvp, makeudev(253, mfs_minor++)); devvp->v_data = mfsp; mfsp->mfs_baseoff = args.base; mfsp->mfs_size = args.size; mfsp->mfs_vnode = devvp; mfsp->mfs_pid = p->p_pid; mfsp->mfs_active = 1; bufq_init(&mfsp->buf_queue); /* * Since this is a new mount, we want the names for * the device and the mount point copied in. If an * error occurs, the mountpoint is discarded by the * upper level code. */ /* Save "last mounted on" info for mount point (NULL pad)*/ copyinstr( path, /* mount point*/ mp->mnt_stat.f_mntonname, /* save area*/ MNAMELEN - 1, /* max size*/ &size); /* real size*/ bzero( mp->mnt_stat.f_mntonname + size, MNAMELEN - size); /* Save "mounted from" info for mount point (NULL pad)*/ copyinstr( args.fspec, /* device name*/ mp->mnt_stat.f_mntfromname, /* save area*/ MNAMELEN - 1, /* max size*/ &size); /* real size*/ bzero( mp->mnt_stat.f_mntfromname + size, MNAMELEN - size); if ((err = ffs_mountfs(devvp, mp, p, M_MFSNODE)) != 0) { mfsp->mfs_active = 0; goto error_2; } #ifdef MFS_ROOT dostatfs: #endif /* * Initialize FS stat information in mount struct; uses both * mp->mnt_stat.f_mntonname and mp->mnt_stat.f_mntfromname * * This code is common to root and non-root mounts */ (void) VFS_STATFS(mp, &mp->mnt_stat, p); goto success; error_2: /* error with devvp held*/ /* release devvp before failing*/ vrele(devvp); error_1: /* no state to back out*/ success: return( err); } static int mfs_pri = PWAIT | PCATCH; /* XXX prob. temp */ /* * Used to grab the process and keep it in the kernel to service * memory filesystem I/O requests. * * Loop servicing I/O requests. * Copy the requested data into or out of the memory filesystem * address space. */ /* ARGSUSED */ static int mfs_start(mp, flags, p) struct mount *mp; int flags; struct proc *p; { register struct vnode *vp = VFSTOUFS(mp)->um_devvp; register struct mfsnode *mfsp = VTOMFS(vp); register struct buf *bp; register int gotsig = 0, sig; /* * We must prevent the system from trying to swap * out or kill ( when swap space is low, see vm/pageout.c ) the * process. A deadlock can occur if the process is swapped out, * and the system can loop trying to kill the unkillable ( while * references exist ) MFS process when swap space is low. */ PHOLD(curproc); while (mfsp->mfs_active) { int s; s = splbio(); while ((bp = bufq_first(&mfsp->buf_queue)) != NULL) { bufq_remove(&mfsp->buf_queue, bp); splx(s); mfs_doio(bp, mfsp); wakeup((caddr_t)bp); s = splbio(); } splx(s); /* * If a non-ignored signal is received, try to unmount. * If that fails, clear the signal (it has been "processed"), * otherwise we will loop here, as tsleep will always return * EINTR/ERESTART. */ /* * Note that dounmount() may fail if work was queued after * we slept. We have to jump hoops here to make sure that we * process any buffers after the sleep, before we dounmount() */ if (gotsig) { gotsig = 0; if (dounmount(mp, 0, p) != 0) { sig = CURSIG(p); if (sig) SIGDELSET(p->p_siglist, sig); } } else if (tsleep((caddr_t)vp, mfs_pri, "mfsidl", 0)) gotsig++; /* try to unmount in next pass */ } return (0); } /* * Get file system statistics. */ static int mfs_statfs(mp, sbp, p) struct mount *mp; struct statfs *sbp; struct proc *p; { int error; error = ffs_statfs(mp, sbp, p); sbp->f_type = mp->mnt_vfc->vfc_typenum; return (error); } /* * Memory based filesystem initialization. */ static int mfs_init(vfsp) struct vfsconf *vfsp; { cdevsw_add(&mfs_cdevsw); return (0); } #ifdef MFS_ROOT /* * Just before root is mounted, check to see if we are a candidate * to supply it. If we have an image available, override the guessed * defaults. */ static void mfs_takeroot(junk) void *junk; { if (bootverbose) printf("Considering MFS root f/s..."); if (mfs_getimage()) { rootdevnames[0] = "mfs:"; printf("preloaded filesystem found.\n"); } else if (bootverbose) { printf("not found.\n"); } } SYSINIT(mfs_root, SI_SUB_MOUNT_ROOT, SI_ORDER_FIRST, mfs_takeroot, NULL); #endif