diff options
| -rw-r--r-- | sys/dev/md/md.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c index 1ed5b71db95d..79bf19c4e5b2 100644 --- a/sys/dev/md/md.c +++ b/sys/dev/md/md.c @@ -205,6 +205,9 @@ struct md_s { vm_object_t object; }; +/* Used for BIO_DELETE on MD_VNODE */ +static u_char zero[PAGE_SIZE]; + static struct indir * new_indir(u_int shift) { @@ -514,10 +517,12 @@ mdstart_vnode(struct md_s *sc, struct bio *bp) struct mount *mp; struct vnode *vp; struct thread *td; + off_t end, zerosize; switch (bp->bio_cmd) { case BIO_READ: case BIO_WRITE: + case BIO_DELETE: case BIO_FLUSH: break; default: @@ -548,6 +553,43 @@ mdstart_vnode(struct md_s *sc, struct bio *bp) bzero(&auio, sizeof(auio)); + /* + * Special case for BIO_DELETE. On the surface, this is very + * similar to BIO_WRITE, except that we write from our own + * fixed-length buffer, so we have to loop. The net result is + * that the two cases end up having very little in common. + */ + if (bp->bio_cmd == BIO_DELETE) { + zerosize = sizeof(zero) - (sizeof(zero) % sc->sectorsize); + auio.uio_iov = &aiov; + auio.uio_iovcnt = 1; + auio.uio_offset = (vm_ooffset_t)bp->bio_offset; + auio.uio_segflg = UIO_SYSSPACE; + auio.uio_rw = UIO_WRITE; + auio.uio_td = td; + end = bp->bio_offset + bp->bio_length; + vfslocked = VFS_LOCK_GIANT(vp->v_mount); + (void) vn_start_write(vp, &mp, V_WAIT); + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); + error = 0; + while (auio.uio_offset < end) { + aiov.iov_base = zero; + aiov.iov_len = end - auio.uio_offset; + if (aiov.iov_len > zerosize) + aiov.iov_len = zerosize; + auio.uio_resid = aiov.iov_len; + error = VOP_WRITE(vp, &auio, + sc->flags & MD_ASYNC ? 0 : IO_SYNC, sc->cred); + if (error != 0) + break; + } + VOP_UNLOCK(vp, 0); + vn_finished_write(mp); + bp->bio_resid = end - auio.uio_offset; + VFS_UNLOCK_GIANT(vfslocked); + return (error); + } + aiov.iov_base = bp->bio_data; aiov.iov_len = bp->bio_length; auio.uio_iov = &aiov; |