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Teach the virtio block device to deal with direct as well as indirect

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descriptors. Prior to this change the device would only work with guests
that chose to use indirect descriptors.

Modify the device reset callback to actually reset the device state.

Submitted by:	Tycho Nightingale (tycho.nightingale@pluribusnetworks.com)
This commit is contained in:
Neel Natu 2013-04-23 16:40:39 +00:00
parent 114a94cc89
commit 3bf0823c5c
1 changed files with 61 additions and 63 deletions
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124
usr.sbin/bhyve/pci_virtio_block.c
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@ -187,6 +187,13 @@ pci_vtblk_update_status(struct pci_vtblk_softc *sc, uint32_t value)
{
if (value == 0) {
DPRINTF(("vtblk: device reset requested !\n"));
sc->vbsc_isr = 0;
sc->msix_table_idx_req = VIRTIO_MSI_NO_VECTOR;
sc->msix_table_idx_cfg = VIRTIO_MSI_NO_VECTOR;
sc->vbsc_features = 0;
sc->vbsc_pfn = 0;
sc->vbsc_lastq = 0;
memset(&sc->vbsc_q, 0, sizeof(struct vring_hqueue));
}
sc->vbsc_status = value;
@ -203,9 +210,8 @@ pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vring_hqueue *hq)
int i;
int err;
int iolen;
int nsegs;
int uidx, aidx, didx;
int writeop, type;
int indirect, writeop, type;
off_t offset;
uidx = *hq->hq_used_idx;
@ -215,30 +221,21 @@ pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vring_hqueue *hq)
vd = &hq->hq_dtable[didx];
/*
* Verify that the descriptor is indirect, and obtain
* the pointer to the indirect descriptor.
* There has to be space for at least 3 descriptors
* in the indirect descriptor array: the block header,
* 1 or more data descriptors, and a status byte.
*/
assert(vd->vd_flags & VRING_DESC_F_INDIRECT);
indirect = ((vd->vd_flags & VRING_DESC_F_INDIRECT) != 0);
nsegs = vd->vd_len / sizeof(struct virtio_desc);
assert(nsegs >= 3);
assert(nsegs < VTBLK_MAXSEGS + 2);
vid = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr, vd->vd_len);
assert((vid->vd_flags & VRING_DESC_F_INDIRECT) == 0);
if (indirect) {
vid = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr, vd->vd_len);
vd = &vid[0];
}
/*
* The first descriptor will be the read-only fixed header
*/
vbh = paddr_guest2host(vtblk_ctx(sc), vid[0].vd_addr,
vbh = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr,
sizeof(struct virtio_blk_hdr));
assert(vid[0].vd_len == sizeof(struct virtio_blk_hdr));
assert(vid[0].vd_flags & VRING_DESC_F_NEXT);
assert((vid[0].vd_flags & VRING_DESC_F_WRITE) == 0);
assert(vd->vd_len == sizeof(struct virtio_blk_hdr));
assert(vd->vd_flags & VRING_DESC_F_NEXT);
assert((vd->vd_flags & VRING_DESC_F_WRITE) == 0);
/*
* XXX
@ -253,14 +250,18 @@ pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vring_hqueue *hq)
/*
* Build up the iovec based on the guest's data descriptors
*/
for (i = 1, iolen = 0; i < nsegs - 1; i++) {
iov[i-1].iov_base = paddr_guest2host(vtblk_ctx(sc),
vid[i].vd_addr, vid[i].vd_len);
iov[i-1].iov_len = vid[i].vd_len;
iolen += vid[i].vd_len;
i = iolen = 0;
while (1) {
if (indirect)
vd = &vid[i + 1]; /* skip first indirect desc */
else
vd = &hq->hq_dtable[vd->vd_next];
assert(vid[i].vd_flags & VRING_DESC_F_NEXT);
assert((vid[i].vd_flags & VRING_DESC_F_INDIRECT) == 0);
if ((vd->vd_flags & VRING_DESC_F_NEXT) == 0)
break;
if (i == VTBLK_MAXSEGS)
break;
/*
* - write op implies read-only descriptor,
@ -268,58 +269,41 @@ pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vring_hqueue *hq)
* therefore test the inverse of the descriptor bit
* to the op.
*/
assert(((vid[i].vd_flags & VRING_DESC_F_WRITE) == 0) ==
assert(((vd->vd_flags & VRING_DESC_F_WRITE) == 0) ==
writeop);
iov[i].iov_base = paddr_guest2host(vtblk_ctx(sc),
vd->vd_addr,
vd->vd_len);
iov[i].iov_len = vd->vd_len;
iolen += vd->vd_len;
i++;
}
/* Lastly, get the address of the status byte */
status = paddr_guest2host(vtblk_ctx(sc), vid[nsegs - 1].vd_addr, 1);
assert(vid[nsegs - 1].vd_len == 1);
assert((vid[nsegs - 1].vd_flags & VRING_DESC_F_NEXT) == 0);
assert(vid[nsegs - 1].vd_flags & VRING_DESC_F_WRITE);
status = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr, 1);
assert(vd->vd_len == 1);
assert((vd->vd_flags & VRING_DESC_F_NEXT) == 0);
assert(vd->vd_flags & VRING_DESC_F_WRITE);
DPRINTF(("virtio-block: %s op, %d bytes, %d segs, offset %ld\n\r",
writeop ? "write" : "read", iolen, nsegs - 2, offset));
writeop ? "write" : "read", iolen, i, offset));
if (writeop){
err = pwritev(sc->vbsc_fd, iov, nsegs - 2, offset);
} else {
err = preadv(sc->vbsc_fd, iov, nsegs - 2, offset);
}
if (writeop)
err = pwritev(sc->vbsc_fd, iov, i, offset);
else
err = preadv(sc->vbsc_fd, iov, i, offset);
*status = err < 0 ? VTBLK_S_IOERR : VTBLK_S_OK;
/*
* Return the single indirect descriptor back to the host
* Return the single descriptor back to the host
*/
vu = &hq->hq_used_ring[uidx % hq->hq_size];
vu->vu_idx = didx;
vu->vu_tlen = 1;
hq->hq_cur_aidx++;
*hq->hq_used_idx += 1;
}
static void
pci_vtblk_qnotify(struct pci_vtblk_softc *sc)
{
struct vring_hqueue *hq = &sc->vbsc_q;
int i;
int ndescs;
/*
* Calculate number of ring entries to process
*/
ndescs = hq_num_avail(hq);
if (ndescs == 0)
return;
/*
* Run through all the entries, placing them into iovecs and
* sending when an end-of-packet is found
*/
for (i = 0; i < ndescs; i++)
pci_vtblk_proc(sc, hq);
/*
* Generate an interrupt if able
@ -332,7 +316,21 @@ pci_vtblk_qnotify(struct pci_vtblk_softc *sc)
pci_generate_msi(sc->vbsc_pi, 0);
}
}
}
static void
pci_vtblk_qnotify(struct pci_vtblk_softc *sc)
{
struct vring_hqueue *hq = &sc->vbsc_q;
int ndescs;
while ((ndescs = hq_num_avail(hq)) != 0) {
/*
* Run through all the entries, placing them into iovecs and
* sending when an end-of-packet is found
*/
pci_vtblk_proc(sc, hq);
}
}
static void