diff options
author | mckusick <mckusick@FreeBSD.org> | 2002-10-25 00:20:37 +0000 |
---|---|---|
committer | mckusick <mckusick@FreeBSD.org> | 2002-10-25 00:20:37 +0000 |
commit | 6b1611bd949afb58a84ad54e4bbcf960b0ef28b1 (patch) | |
tree | 3538f027616418c955bda99415bbb0b81e6d64b5 /sys | |
parent | 776a2129fe77eb14c0d61bf67d393ee4893c4a08 (diff) | |
download | FreeBSD-src-6b1611bd949afb58a84ad54e4bbcf960b0ef28b1.zip FreeBSD-src-6b1611bd949afb58a84ad54e4bbcf960b0ef28b1.tar.gz |
Within ufs, the ffs_sync and ffs_fsync functions did not always
check for and/or report I/O errors. The result is that a VFS_SYNC
or VOP_FSYNC called with MNT_WAIT could loop infinitely on ufs in
the presence of a hard error writing a disk sector or in a filesystem
full condition. This patch ensures that I/O errors will always be
checked and returned. This patch also ensures that every call to
VFS_SYNC or VOP_FSYNC with MNT_WAIT set checks for and takes
appropriate action when an error is returned.
Sponsored by: DARPA & NAI Labs.
Diffstat (limited to 'sys')
-rw-r--r-- | sys/fs/specfs/spec_vnops.c | 18 | ||||
-rw-r--r-- | sys/kern/vfs_subr.c | 6 | ||||
-rw-r--r-- | sys/kern/vfs_vnops.c | 11 | ||||
-rw-r--r-- | sys/sys/vnode.h | 2 | ||||
-rw-r--r-- | sys/ufs/ffs/ffs_snapshot.c | 5 | ||||
-rw-r--r-- | sys/ufs/ffs/ffs_vfsops.c | 10 |
6 files changed, 37 insertions, 15 deletions
diff --git a/sys/fs/specfs/spec_vnops.c b/sys/fs/specfs/spec_vnops.c index 9ae87c0..ed5c2bc 100644 --- a/sys/fs/specfs/spec_vnops.c +++ b/sys/fs/specfs/spec_vnops.c @@ -421,8 +421,8 @@ spec_fsync(ap) struct vnode *vp = ap->a_vp; struct buf *bp; struct buf *nbp; - int s; - int maxretry = 10000; /* large, arbitrarily chosen */ + int s, error = 0; + int maxretry = 100; /* large, arbitrarily chosen */ if (!vn_isdisk(vp, NULL)) return (0); @@ -435,6 +435,7 @@ loop1: s = splbio(); TAILQ_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs) { bp->b_flags &= ~B_SCANNED; + bp->b_error = 0; } splx(s); @@ -481,16 +482,25 @@ loop2: PRIBIO + 1, "spfsyn", 0); } if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { - if (--maxretry != 0) { + /* + * If we are unable to write any of these buffers + * then we fail now rather than trying endlessly + * to write them out. + */ + TAILQ_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs) + if ((error = bp->b_error) == 0) + continue; + if (error == 0 && --maxretry >= 0) { splx(s); goto loop1; } vprint("spec_fsync: giving up on dirty", vp); + error = EAGAIN; } } VI_UNLOCK(vp); splx(s); - return (0); + return (error); } /* diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c index e0256ad..8f35ddb 100644 --- a/sys/kern/vfs_subr.c +++ b/sys/kern/vfs_subr.c @@ -3425,7 +3425,7 @@ sync_fsync(ap) struct vnode *syncvp = ap->a_vp; struct mount *mp = syncvp->v_mount; struct thread *td = ap->a_td; - int asyncflag; + int error, asyncflag; /* * We only need to do something if this is a lazy evaluation. @@ -3456,12 +3456,12 @@ sync_fsync(ap) asyncflag = mp->mnt_flag & MNT_ASYNC; mp->mnt_flag &= ~MNT_ASYNC; vfs_msync(mp, MNT_NOWAIT); - VFS_SYNC(mp, MNT_LAZY, ap->a_cred, td); + error = VFS_SYNC(mp, MNT_LAZY, ap->a_cred, td); if (asyncflag) mp->mnt_flag |= MNT_ASYNC; vn_finished_write(mp); vfs_unbusy(mp, td); - return (0); + return (error); } /* diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c index 08f8093..0281a29 100644 --- a/sys/kern/vfs_vnops.c +++ b/sys/kern/vfs_vnops.c @@ -1005,19 +1005,24 @@ vn_finished_write(mp) /* * Request a filesystem to suspend write operations. */ -void +int vfs_write_suspend(mp) struct mount *mp; { struct thread *td = curthread; + int error; if (mp->mnt_kern_flag & MNTK_SUSPEND) - return; + return (0); mp->mnt_kern_flag |= MNTK_SUSPEND; if (mp->mnt_writeopcount > 0) (void) tsleep(&mp->mnt_writeopcount, PUSER - 1, "suspwt", 0); - VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td); + if ((error = VFS_SYNC(mp, MNT_WAIT, td->td_ucred, td)) != 0) { + vfs_write_resume(mp); + return (error); + } mp->mnt_kern_flag |= MNTK_SUSPENDED; + return (0); } /* diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h index 2284127..9d7ca0d 100644 --- a/sys/sys/vnode.h +++ b/sys/sys/vnode.h @@ -681,7 +681,7 @@ int vfs_object_create(struct vnode *vp, struct thread *td, struct ucred *cred); void vfs_timestamp(struct timespec *); void vfs_write_resume(struct mount *mp); -void vfs_write_suspend(struct mount *mp); +int vfs_write_suspend(struct mount *mp); int vop_stdbmap(struct vop_bmap_args *); int vop_stdgetwritemount(struct vop_getwritemount_args *); int vop_stdgetpages(struct vop_getpages_args *); diff --git a/sys/ufs/ffs/ffs_snapshot.c b/sys/ufs/ffs/ffs_snapshot.c index 1b4efb2..5040cb0 100644 --- a/sys/ufs/ffs/ffs_snapshot.c +++ b/sys/ufs/ffs/ffs_snapshot.c @@ -307,7 +307,10 @@ restart: */ for (;;) { vn_finished_write(wrtmp); - vfs_write_suspend(vp->v_mount); + if ((error = vfs_write_suspend(vp->v_mount)) != 0) { + vn_start_write(NULL, &wrtmp, V_WAIT); + goto out; + } if (mp->mnt_kern_flag & MNTK_SUSPENDED) break; vn_start_write(NULL, &wrtmp, V_WAIT); diff --git a/sys/ufs/ffs/ffs_vfsops.c b/sys/ufs/ffs/ffs_vfsops.c index 76e243e..b80cd1c 100644 --- a/sys/ufs/ffs/ffs_vfsops.c +++ b/sys/ufs/ffs/ffs_vfsops.c @@ -184,7 +184,11 @@ ffs_mount(mp, path, data, ndp, td) /* * Flush any dirty data. */ - VFS_SYNC(mp, MNT_WAIT, td->td_proc->p_ucred, td); + if ((error = VFS_SYNC(mp, MNT_WAIT, + td->td_proc->p_ucred, td)) != 0) { + vn_finished_write(mp); + return (error); + } /* * Check for and optionally get rid of files open * for writing. @@ -1156,7 +1160,7 @@ loop: if ((error = softdep_flushworklist(ump->um_mountp, &count, td))) allerror = error; /* Flushed work items may create new vnodes to clean */ - if (count) { + if (allerror == 0 && count) { mtx_lock(&mntvnode_mtx); goto loop; } @@ -1172,7 +1176,7 @@ loop: if ((error = VOP_FSYNC(devvp, cred, waitfor, td)) != 0) allerror = error; VOP_UNLOCK(devvp, 0, td); - if (waitfor == MNT_WAIT) { + if (allerror == 0 && waitfor == MNT_WAIT) { mtx_lock(&mntvnode_mtx); goto loop; } |