Index: head/sys/ufs/ffs/ffs_suspend.c =================================================================== --- head/sys/ufs/ffs/ffs_suspend.c (revision 358811) +++ head/sys/ufs/ffs/ffs_suspend.c (revision 358812) @@ -1,354 +1,354 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2012 The FreeBSD Foundation * All rights reserved. * * This software was developed by Edward Tomasz Napierala under sponsorship * from the FreeBSD Foundation. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. * * $FreeBSD$ */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static d_open_t ffs_susp_open; static d_write_t ffs_susp_rdwr; static d_ioctl_t ffs_susp_ioctl; static struct cdevsw ffs_susp_cdevsw = { .d_version = D_VERSION, .d_open = ffs_susp_open, .d_read = ffs_susp_rdwr, .d_write = ffs_susp_rdwr, .d_ioctl = ffs_susp_ioctl, .d_name = "ffs_susp", }; static struct cdev *ffs_susp_dev; static struct sx ffs_susp_lock; static int ffs_susp_suspended(struct mount *mp) { struct ufsmount *ump; sx_assert(&ffs_susp_lock, SA_LOCKED); ump = VFSTOUFS(mp); if ((ump->um_flags & UM_WRITESUSPENDED) != 0) return (1); return (0); } static int ffs_susp_open(struct cdev *dev __unused, int flags __unused, int fmt __unused, struct thread *td __unused) { return (0); } static int ffs_susp_rdwr(struct cdev *dev, struct uio *uio, int ioflag) { int error, i; struct vnode *devvp; struct mount *mp; struct ufsmount *ump; struct buf *bp; void *base; size_t len; ssize_t cnt; struct fs *fs; sx_slock(&ffs_susp_lock); error = devfs_get_cdevpriv((void **)&mp); if (error != 0) { sx_sunlock(&ffs_susp_lock); return (ENXIO); } ump = VFSTOUFS(mp); devvp = ump->um_devvp; fs = ump->um_fs; if (ffs_susp_suspended(mp) == 0) { sx_sunlock(&ffs_susp_lock); return (ENXIO); } KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE, ("neither UIO_READ or UIO_WRITE")); KASSERT(uio->uio_segflg == UIO_USERSPACE, ("uio->uio_segflg != UIO_USERSPACE")); cnt = uio->uio_resid; for (i = 0; i < uio->uio_iovcnt; i++) { while (uio->uio_iov[i].iov_len) { base = uio->uio_iov[i].iov_base; len = uio->uio_iov[i].iov_len; if (len > fs->fs_bsize) len = fs->fs_bsize; if (fragoff(fs, uio->uio_offset) != 0 || fragoff(fs, len) != 0) { error = EINVAL; goto out; } error = bread(devvp, btodb(uio->uio_offset), len, NOCRED, &bp); if (error != 0) goto out; if (uio->uio_rw == UIO_WRITE) { error = copyin(base, bp->b_data, len); if (error != 0) { bp->b_flags |= B_INVAL | B_NOCACHE; brelse(bp); goto out; } error = bwrite(bp); if (error != 0) goto out; } else { error = copyout(bp->b_data, base, len); brelse(bp); if (error != 0) goto out; } uio->uio_iov[i].iov_base = (char *)uio->uio_iov[i].iov_base + len; uio->uio_iov[i].iov_len -= len; uio->uio_resid -= len; uio->uio_offset += len; } } out: sx_sunlock(&ffs_susp_lock); if (uio->uio_resid < cnt) return (0); return (error); } static int ffs_susp_suspend(struct mount *mp) { struct ufsmount *ump; int error; sx_assert(&ffs_susp_lock, SA_XLOCKED); if (!ffs_own_mount(mp)) return (EINVAL); if (ffs_susp_suspended(mp)) return (EBUSY); ump = VFSTOUFS(mp); /* * Make sure the calling thread is permitted to access the mounted * device. The permissions can change after we unlock the vnode; * it's harmless. */ - vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY); - error = VOP_ACCESS(ump->um_devvp, VREAD | VWRITE, + vn_lock(ump->um_odevvp, LK_EXCLUSIVE | LK_RETRY); + error = VOP_ACCESS(ump->um_odevvp, VREAD | VWRITE, curthread->td_ucred, curthread); - VOP_UNLOCK(ump->um_devvp); + VOP_UNLOCK(ump->um_odevvp); if (error != 0) return (error); #ifdef MAC if (mac_mount_check_stat(curthread->td_ucred, mp) != 0) return (EPERM); #endif if ((error = vfs_write_suspend(mp, VS_SKIP_UNMOUNT)) != 0) return (error); UFS_LOCK(ump); ump->um_flags |= UM_WRITESUSPENDED; UFS_UNLOCK(ump); return (0); } static void ffs_susp_unsuspend(struct mount *mp) { struct ufsmount *ump; sx_assert(&ffs_susp_lock, SA_XLOCKED); /* * XXX: The status is kept per-process; the vfs_write_resume() routine * asserts that the resuming thread is the same one that called * vfs_write_suspend(). The cdevpriv data, however, is attached * to the file descriptor, e.g. is inherited during fork. Thus, * it's possible that the resuming process will be different from * the one that started the suspension. * * Work around by fooling the check in vfs_write_resume(). */ mp->mnt_susp_owner = curthread; vfs_write_resume(mp, 0); ump = VFSTOUFS(mp); UFS_LOCK(ump); ump->um_flags &= ~UM_WRITESUSPENDED; UFS_UNLOCK(ump); vfs_unbusy(mp); } static void ffs_susp_dtor(void *data) { struct fs *fs; struct ufsmount *ump; struct mount *mp; int error; sx_xlock(&ffs_susp_lock); mp = (struct mount *)data; ump = VFSTOUFS(mp); fs = ump->um_fs; if (ffs_susp_suspended(mp) == 0) { sx_xunlock(&ffs_susp_lock); return; } KASSERT((mp->mnt_kern_flag & MNTK_SUSPEND) != 0, ("MNTK_SUSPEND not set")); error = ffs_reload(mp, curthread, FFSR_FORCE | FFSR_UNSUSPEND); if (error != 0) panic("failed to unsuspend writes on %s", fs->fs_fsmnt); ffs_susp_unsuspend(mp); sx_xunlock(&ffs_susp_lock); } static int ffs_susp_ioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td) { struct mount *mp; fsid_t *fsidp; int error; /* * No suspend inside the jail. Allowing it would require making * sure that e.g. the devfs ruleset for that jail permits access * to the devvp. */ if (jailed(td->td_ucred)) return (EPERM); sx_xlock(&ffs_susp_lock); switch (cmd) { case UFSSUSPEND: fsidp = (fsid_t *)addr; mp = vfs_getvfs(fsidp); if (mp == NULL) { error = ENOENT; break; } error = vfs_busy(mp, 0); vfs_rel(mp); if (error != 0) break; error = ffs_susp_suspend(mp); if (error != 0) { vfs_unbusy(mp); break; } error = devfs_set_cdevpriv(mp, ffs_susp_dtor); if (error != 0) ffs_susp_unsuspend(mp); break; case UFSRESUME: error = devfs_get_cdevpriv((void **)&mp); if (error != 0) break; /* * This calls ffs_susp_dtor, which in turn unsuspends the fs. * The dtor expects to be called without lock held, because * sometimes it's called from here, and sometimes due to the * file being closed or process exiting. */ sx_xunlock(&ffs_susp_lock); devfs_clear_cdevpriv(); return (0); default: error = ENXIO; break; } sx_xunlock(&ffs_susp_lock); return (error); } void ffs_susp_initialize(void) { sx_init(&ffs_susp_lock, "ffs_susp"); ffs_susp_dev = make_dev(&ffs_susp_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "ufssuspend"); } void ffs_susp_uninitialize(void) { destroy_dev(ffs_susp_dev); sx_destroy(&ffs_susp_lock); }