/* * 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: src/sys/ufs/mfs/mfs_vfsops.c,v 1.81.2.3 2001/07/04 17:35:21 tegge Exp $ * $DragonFly: src/sys/vfs/mfs/mfs_vfsops.c,v 1.23 2005/07/26 15:43:35 hmp Exp $ */ #include "opt_mfs.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "mfsnode.h" #include "mfs_extern.h" MALLOC_DEFINE(M_MFSNODE, "MFS node", "MFS vnode private part"); extern struct vop_ops *mfs_vnode_vops; static int mfs_mount (struct mount *mp, char *path, caddr_t data, struct thread *td); static int mfs_start (struct mount *mp, int flags, struct thread *td); static int mfs_statfs (struct mount *mp, struct statfs *sbp, struct thread *td); static int mfs_init (struct vfsconf *); d_open_t mfsopen; d_close_t mfsclose; d_strategy_t mfsstrategy; #define MFS_CDEV_MAJOR 253 static struct cdevsw mfs_cdevsw = { /* name */ "MFS", /* maj */ MFS_CDEV_MAJOR, /* flags */ D_DISK, /* port */ NULL, /* clone */ NULL, /* open */ mfsopen, /* close */ mfsclose, /* read */ physread, /* write */ physwrite, /* ioctl */ noioctl, /* poll */ nopoll, /* mmap */ nommap, /* strategy */ mfsstrategy, /* dump */ nodump, /* psize */ nopsize }; /* * mfs vfs operations. */ static struct vfsops mfs_vfsops = { .vfs_mount = mfs_mount, .vfs_start = mfs_start, .vfs_unmount = ffs_unmount, .vfs_root = ufs_root, .vfs_quotactl = ufs_quotactl, .vfs_statfs = mfs_statfs, .vfs_sync = ffs_sync, .vfs_vget = ffs_vget, .vfs_fhtovp = ffs_fhtovp, .vfs_checkexp = ufs_check_export, .vfs_vptofh = ffs_vptofh, .vfs_init = mfs_init }; VFS_SET(mfs_vfsops, mfs, 0); /* * We allow the underlying MFS block device to be opened and read. */ int mfsopen(dev_t dev, int flags, int mode, struct thread *td) { if (flags & FWRITE) return(EROFS); if (dev->si_drv1) return(0); return(ENXIO); } int mfsclose(dev_t dev, int flags, int mode, struct thread *td) { return(0); } void mfsstrategy(struct buf *bp) { struct mfsnode *mfsp; if ((mfsp = bp->b_dev->si_drv1) != NULL) { off_t boff = (off_t)bp->b_blkno << DEV_BSHIFT; off_t eoff = boff + bp->b_bcount; if (eoff <= mfsp->mfs_size) { bufq_insert_tail(&mfsp->buf_queue, bp); wakeup((caddr_t)mfsp); } else if (boff < mfsp->mfs_size) { bp->b_bcount = mfsp->mfs_size - boff; bufq_insert_tail(&mfsp->buf_queue, bp); wakeup((caddr_t)mfsp); } else if (boff == mfsp->mfs_size) { bp->b_resid = bp->b_bcount; biodone(bp); } else { bp->b_error = EINVAL; biodone(bp); } } else { bp->b_error = ENXIO; bp->b_flags |= B_ERROR; biodone(bp); } } /* * 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(struct mount *mp, char *path, caddr_t data, struct thread *td) { struct vnode *devvp; struct mfs_args args; struct ufsmount *ump; struct fs *fs; struct mfsnode *mfsp; size_t size; int flags, err; int minnum; dev_t dev; /* * Use NULL path to flag a root mount */ if( path == NULL) { /* *** * Mounting root file system *** */ /* you lose */ panic("mfs_mount: mount MFS as root: not configured!"); } /* *** * 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, td); 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 = getspecialvnode(VT_MFS, NULL, &mfs_vnode_vops, &devvp, 0, 0); if (err) { FREE(mfsp, M_MFSNODE); goto error_1; } minnum = (curproc->p_pid & 0xFF) | ((curproc->p_pid & ~0xFF) << 8); devvp->v_type = VCHR; dev = make_dev(&mfs_cdevsw, minnum, UID_ROOT, GID_WHEEL, 0600, "MFS%d", minnum >> 16); /* It is not clear that these will get initialized otherwise */ dev->si_bsize_phys = DEV_BSIZE; dev->si_iosize_max = DFLTPHYS; dev->si_drv1 = mfsp; addaliasu(devvp, makeudev(MFS_CDEV_MAJOR, minnum)); devvp->v_data = mfsp; mfsp->mfs_baseoff = args.base; mfsp->mfs_size = args.size; mfsp->mfs_vnode = devvp; mfsp->mfs_dev = reference_dev(dev); mfsp->mfs_td = td; mfsp->mfs_active = 1; bufq_init(&mfsp->buf_queue); /* 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); vx_unlock(devvp); if ((err = ffs_mountfs(devvp, mp, td, M_MFSNODE)) != 0) { mfsp->mfs_active = 0; goto error_2; } /* * Initialize FS stat information in mount struct; uses * mp->mnt_stat.f_mntfromname. * * This code is common to root and non-root mounts */ (void) VFS_STATFS(mp, &mp->mnt_stat, td); goto success; error_2: /* error with devvp held*/ /* release devvp before failing*/ vrele(devvp); error_1: /* no state to back out*/ success: return( err); } /* * 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(struct mount *mp, int flags, struct thread *td) { struct vnode *vp = VFSTOUFS(mp)->um_devvp; struct mfsnode *mfsp = VTOMFS(vp); struct buf *bp; 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. */ KKASSERT(curproc); PHOLD(curproc); while (mfsp->mfs_active) { crit_enter(); while ((bp = bufq_first(&mfsp->buf_queue)) != NULL) { bufq_remove(&mfsp->buf_queue, bp); crit_exit(); mfs_doio(bp, mfsp); wakeup((caddr_t)bp); crit_enter(); } crit_exit(); /* * 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, td) != 0) { KKASSERT(td->td_proc); sig = CURSIG(td->td_proc); if (sig) SIGDELSET(td->td_proc->p_siglist, sig); } } else if (tsleep((caddr_t)mfsp, PCATCH, "mfsidl", 0)) gotsig++; /* try to unmount in next pass */ } PRELE(curproc); v_release_rdev(vp); /* hack because we do not implement CLOSE */ /* XXX destroy/release devvp */ return (0); } /* * Get file system statistics. */ static int mfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) { int error; error = ffs_statfs(mp, sbp, td); sbp->f_type = mp->mnt_vfc->vfc_typenum; return (error); } /* * Memory based filesystem initialization. */ static int mfs_init(struct vfsconf *vfsp) { cdevsw_add(&mfs_cdevsw, 0, 0); return (0); }