diff options
author | mckusick <mckusick@FreeBSD.org> | 2011-07-15 16:20:33 +0000 |
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committer | mckusick <mckusick@FreeBSD.org> | 2011-07-15 16:20:33 +0000 |
commit | 40b131bdaf10a8762fefdeac2b6c7a8ae66e57e4 (patch) | |
tree | e87078f33cf4278b1800e57f6848d440f4f065cc /sys/ufs/ffs/ffs_alloc.c | |
parent | 2c393993a1f216cedd310d2f90bd208bf62fd4e0 (diff) | |
download | FreeBSD-src-40b131bdaf10a8762fefdeac2b6c7a8ae66e57e4.zip FreeBSD-src-40b131bdaf10a8762fefdeac2b6c7a8ae66e57e4.tar.gz |
Add an FFS specific mount option to allow a filesystem checker
(typically fsck_ffs) to register that it wishes to use FFS specific
sysctl's to update the filesystem. This ensures that two checkers
cannot run on a given filesystem at the same time and that no other
process accidentally or maliciously uses the filesystem updating
sysctls inappropriately. This functionality is needed by the
journaling soft-updates recovery code.
Diffstat (limited to 'sys/ufs/ffs/ffs_alloc.c')
-rw-r--r-- | sys/ufs/ffs/ffs_alloc.c | 185 |
1 files changed, 177 insertions, 8 deletions
diff --git a/sys/ufs/ffs/ffs_alloc.c b/sys/ufs/ffs/ffs_alloc.c index 357b152..82506fb 100644 --- a/sys/ufs/ffs/ffs_alloc.c +++ b/sys/ufs/ffs/ffs_alloc.c @@ -2381,6 +2381,18 @@ ffs_fserr(fs, inum, cp) * in the current directory is oldvalue then change it to newvalue. * unlink(nameptr, oldvalue) - Verify that the inode number associated * with nameptr in the current directory is oldvalue then unlink it. + * + * The following functions may only be used on a quiescent filesystem + * by the soft updates journal. They are not safe to be run on an active + * filesystem. + * + * setinode(inode, dip) - the specified disk inode is replaced with the + * contents pointed to by dip. + * setbufoutput(fd, flags) - output associated with the specified file + * descriptor (which must reference the character device supporting + * the filesystem) switches from using physio to running through the + * buffer cache when flags is set to 1. The descriptor reverts to + * physio for output when flags is set to zero. */ static int sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS); @@ -2427,11 +2439,21 @@ static SYSCTL_NODE(_vfs_ffs, FFS_SET_DOTDOT, setdotdot, CTLFLAG_WR, static SYSCTL_NODE(_vfs_ffs, FFS_UNLINK, unlink, CTLFLAG_WR, sysctl_ffs_fsck, "Unlink a Duplicate Name"); +static SYSCTL_NODE(_vfs_ffs, FFS_SET_INODE, setinode, CTLFLAG_WR, + sysctl_ffs_fsck, "Update an On-Disk Inode"); + +static SYSCTL_NODE(_vfs_ffs, FFS_SET_BUFOUTPUT, setbufoutput, CTLFLAG_WR, + sysctl_ffs_fsck, "Set Buffered Writing for Descriptor"); + +#define DEBUG 1 #ifdef DEBUG -static int fsckcmds = 0; +static int fsckcmds = 1; SYSCTL_INT(_debug, OID_AUTO, fsckcmds, CTLFLAG_RW, &fsckcmds, 0, ""); #endif /* DEBUG */ +static int buffered_write(struct file *, struct uio *, struct ucred *, + int, struct thread *); + static int sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) { @@ -2445,8 +2467,10 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) ufs2_daddr_t blkno; long blkcnt, blksize; struct filedesc *fdp; - struct file *fp; + struct file *fp, *vfp; int vfslocked, filetype, error; + static struct fileops *origops, bufferedops; + static int outcnt = 0; if (req->newlen > sizeof cmd) return (EBADRPC); @@ -2454,7 +2478,7 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) return (error); if (cmd.version != FFS_CMD_VERSION) return (ERPCMISMATCH); - if ((error = getvnode(curproc->p_fd, cmd.handle, &fp)) != 0) + if ((error = getvnode(td->td_proc->p_fd, cmd.handle, &fp)) != 0) return (error); vp = fp->f_data; if (vp->v_type != VREG && vp->v_type != VDIR) { @@ -2467,12 +2491,13 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) fdrop(fp, td); return (EINVAL); } - if (mp->mnt_flag & MNT_RDONLY) { + ump = VFSTOUFS(mp); + if ((mp->mnt_flag & MNT_RDONLY) && + ump->um_fsckpid != td->td_proc->p_pid) { vn_finished_write(mp); fdrop(fp, td); return (EROFS); } - ump = VFSTOUFS(mp); fs = ump->um_fs; filetype = IFREG; @@ -2493,7 +2518,7 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) case FFS_ADJ_REFCNT: #ifdef DEBUG if (fsckcmds) { - printf("%s: adjust inode %jd count by %jd\n", + printf("%s: adjust inode %jd link count by %jd\n", mp->mnt_stat.f_mntonname, (intmax_t)cmd.value, (intmax_t)cmd.size); } @@ -2504,7 +2529,8 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) ip->i_nlink += cmd.size; DIP_SET(ip, i_nlink, ip->i_nlink); ip->i_effnlink += cmd.size; - ip->i_flag |= IN_CHANGE; + ip->i_flag |= IN_CHANGE | IN_MODIFIED; + error = ffs_update(vp, 1); if (DOINGSOFTDEP(vp)) softdep_change_linkcnt(ip); vput(vp); @@ -2522,7 +2548,8 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) break; ip = VTOI(vp); DIP_SET(ip, i_blocks, DIP(ip, i_blocks) + cmd.size); - ip->i_flag |= IN_CHANGE; + ip->i_flag |= IN_CHANGE | IN_MODIFIED; + error = ffs_update(vp, 1); vput(vp); break; @@ -2722,6 +2749,78 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) UIO_USERSPACE, (ino_t)cmd.size); break; + case FFS_SET_INODE: + if (ump->um_fsckpid != td->td_proc->p_pid) { + error = EPERM; + break; + } +#ifdef DEBUG + if (fsckcmds && outcnt++ < 100) { + printf("%s: update inode %jd\n", + mp->mnt_stat.f_mntonname, (intmax_t)cmd.value); + } +#endif /* DEBUG */ + if ((error = ffs_vget(mp, (ino_t)cmd.value, LK_EXCLUSIVE, &vp))) + break; + vfslocked = VFS_LOCK_GIANT(vp->v_mount); + AUDIT_ARG_VNODE1(vp); + ip = VTOI(vp); + if (ip->i_ump->um_fstype == UFS1) + error = copyin((void *)(intptr_t)cmd.size, ip->i_din1, + sizeof(struct ufs1_dinode)); + else + error = copyin((void *)(intptr_t)cmd.size, ip->i_din2, + sizeof(struct ufs2_dinode)); + if (error) { + vput(vp); + VFS_UNLOCK_GIANT(vfslocked); + break; + } + ip->i_flag |= IN_CHANGE | IN_MODIFIED; + error = ffs_update(vp, 1); + vput(vp); + VFS_UNLOCK_GIANT(vfslocked); + break; + + case FFS_SET_BUFOUTPUT: + if (ump->um_fsckpid != td->td_proc->p_pid) { + error = EPERM; + break; + } + if (VTOI(vp)->i_ump != ump) { + error = EINVAL; + break; + } +#ifdef DEBUG + if (fsckcmds) { + printf("%s: %s buffered output for descriptor %jd\n", + mp->mnt_stat.f_mntonname, + cmd.size == 1 ? "enable" : "disable", + (intmax_t)cmd.value); + } +#endif /* DEBUG */ + if ((error = getvnode(td->td_proc->p_fd, cmd.value, &vfp)) != 0) + break; + if (vfp->f_vnode->v_type != VCHR) { + fdrop(vfp, td); + error = EINVAL; + break; + } + if (origops == NULL) { + origops = vfp->f_ops; + bcopy((void *)origops, (void *)&bufferedops, + sizeof(bufferedops)); + bufferedops.fo_write = buffered_write; + } + if (cmd.size == 1) + atomic_store_rel_ptr((volatile uintptr_t *)&vfp->f_ops, + (uintptr_t)&bufferedops); + else + atomic_store_rel_ptr((volatile uintptr_t *)&vfp->f_ops, + (uintptr_t)origops); + fdrop(vfp, td); + break; + default: #ifdef DEBUG if (fsckcmds) { @@ -2737,3 +2836,73 @@ sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS) vn_finished_write(mp); return (error); } + +/* + * Function to switch a descriptor to use the buffer cache to stage + * its I/O. This is needed so that writes to the filesystem device + * will give snapshots a chance to copy modified blocks for which it + * needs to retain copies. + */ +static int +buffered_write(fp, uio, active_cred, flags, td) + struct file *fp; + struct uio *uio; + struct ucred *active_cred; + int flags; + struct thread *td; +{ + struct vnode *devvp; + struct inode *ip; + struct buf *bp; + struct fs *fs; + int error, vfslocked; + daddr_t lbn; + static int outcnt = 0; + + /* + * The devvp is associated with the /dev filesystem. To discover + * the filesystem with which the device is associated, we depend + * on the application setting the current directory to a location + * within the filesystem being written. Yes, this is an ugly hack. + */ + devvp = fp->f_vnode; + ip = VTOI(td->td_proc->p_fd->fd_cdir); + if (ip->i_devvp != devvp) + return (EINVAL); + fs = ip->i_fs; + vfslocked = VFS_LOCK_GIANT(ip->i_vnode->v_mount); + vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); + if ((flags & FOF_OFFSET) == 0) + uio->uio_offset = fp->f_offset; +#ifdef DEBUG + if (fsckcmds && outcnt++ < 100) { + printf("%s: buffered write for block %jd\n", + fs->fs_fsmnt, (intmax_t)btodb(uio->uio_offset)); + } +#endif /* DEBUG */ + /* + * All I/O must be contained within a filesystem block, start on + * a fragment boundary, and be a multiple of fragments in length. + */ + if (uio->uio_resid > fs->fs_bsize - (uio->uio_offset % fs->fs_bsize) || + fragoff(fs, uio->uio_offset) != 0 || + fragoff(fs, uio->uio_resid) != 0) { + error = EINVAL; + goto out; + } + lbn = numfrags(fs, uio->uio_offset); + bp = getblk(devvp, lbn, uio->uio_resid, 0, 0, 0); + bp->b_flags |= B_RELBUF; + if ((error = uiomove((char *)bp->b_data, uio->uio_resid, uio)) != 0) { + brelse(bp); + goto out; + } + error = bwrite(bp); + if ((flags & FOF_OFFSET) == 0) + fp->f_offset = uio->uio_offset; + fp->f_nextoff = uio->uio_offset; +out: + VOP_UNLOCK(devvp, 0); + VFS_UNLOCK_GIANT(vfslocked); + return (error); +} |