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Diffstat (limited to 'sys/dev/xen/blkfront/blkfront.c')
-rw-r--r--sys/dev/xen/blkfront/blkfront.c115
1 files changed, 94 insertions, 21 deletions
diff --git a/sys/dev/xen/blkfront/blkfront.c b/sys/dev/xen/blkfront/blkfront.c
index 0610732..1416c28 100644
--- a/sys/dev/xen/blkfront/blkfront.c
+++ b/sys/dev/xen/blkfront/blkfront.c
@@ -60,7 +60,6 @@ __FBSDID("$FreeBSD$");
#include <xen/xenbus/xenbusvar.h>
#include <machine/_inttypes.h>
-#include <machine/xen/xenvar.h>
#include <geom/geom_disk.h>
@@ -84,6 +83,11 @@ static void xbd_startio(struct xbd_softc *sc);
/*---------------------------- Global Static Data ----------------------------*/
static MALLOC_DEFINE(M_XENBLOCKFRONT, "xbd", "Xen Block Front driver data");
+static int xbd_enable_indirect = 1;
+SYSCTL_NODE(_hw, OID_AUTO, xbd, CTLFLAG_RD, 0, "xbd driver parameters");
+SYSCTL_INT(_hw_xbd, OID_AUTO, xbd_enable_indirect, CTLFLAG_RDTUN,
+ &xbd_enable_indirect, 0, "Enable xbd indirect segments");
+
/*---------------------------- Command Processing ----------------------------*/
static void
xbd_freeze(struct xbd_softc *sc, xbd_flag_t xbd_flag)
@@ -205,7 +209,6 @@ xbd_queue_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
{
struct xbd_softc *sc;
struct xbd_command *cm;
- blkif_request_t *ring_req;
int op;
cm = arg;
@@ -218,22 +221,47 @@ xbd_queue_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
return;
}
- KASSERT(nsegs <= BLKIF_MAX_SEGMENTS_PER_REQUEST,
+ KASSERT(nsegs <= sc->xbd_max_request_segments,
("Too many segments in a blkfront I/O"));
- /* Fill out a communications ring structure. */
- ring_req = RING_GET_REQUEST(&sc->xbd_ring, sc->xbd_ring.req_prod_pvt);
- sc->xbd_ring.req_prod_pvt++;
- ring_req->id = cm->cm_id;
- ring_req->operation = cm->cm_operation;
- ring_req->sector_number = cm->cm_sector_number;
- ring_req->handle = (blkif_vdev_t)(uintptr_t)sc->xbd_disk;
- ring_req->nr_segments = nsegs;
- cm->cm_nseg = nsegs;
- xbd_mksegarray(segs, nsegs, &cm->cm_gref_head,
- xenbus_get_otherend_id(sc->xbd_dev),
- cm->cm_operation == BLKIF_OP_WRITE,
- cm->cm_sg_refs, ring_req->seg);
+ if (nsegs <= BLKIF_MAX_SEGMENTS_PER_REQUEST) {
+ blkif_request_t *ring_req;
+
+ /* Fill out a blkif_request_t structure. */
+ ring_req = (blkif_request_t *)
+ RING_GET_REQUEST(&sc->xbd_ring, sc->xbd_ring.req_prod_pvt);
+ sc->xbd_ring.req_prod_pvt++;
+ ring_req->id = cm->cm_id;
+ ring_req->operation = cm->cm_operation;
+ ring_req->sector_number = cm->cm_sector_number;
+ ring_req->handle = (blkif_vdev_t)(uintptr_t)sc->xbd_disk;
+ ring_req->nr_segments = nsegs;
+ cm->cm_nseg = nsegs;
+ xbd_mksegarray(segs, nsegs, &cm->cm_gref_head,
+ xenbus_get_otherend_id(sc->xbd_dev),
+ cm->cm_operation == BLKIF_OP_WRITE,
+ cm->cm_sg_refs, ring_req->seg);
+ } else {
+ blkif_request_indirect_t *ring_req;
+
+ /* Fill out a blkif_request_indirect_t structure. */
+ ring_req = (blkif_request_indirect_t *)
+ RING_GET_REQUEST(&sc->xbd_ring, sc->xbd_ring.req_prod_pvt);
+ sc->xbd_ring.req_prod_pvt++;
+ ring_req->id = cm->cm_id;
+ ring_req->operation = BLKIF_OP_INDIRECT;
+ ring_req->indirect_op = cm->cm_operation;
+ ring_req->sector_number = cm->cm_sector_number;
+ ring_req->handle = (blkif_vdev_t)(uintptr_t)sc->xbd_disk;
+ ring_req->nr_segments = nsegs;
+ cm->cm_nseg = nsegs;
+ xbd_mksegarray(segs, nsegs, &cm->cm_gref_head,
+ xenbus_get_otherend_id(sc->xbd_dev),
+ cm->cm_operation == BLKIF_OP_WRITE,
+ cm->cm_sg_refs, cm->cm_indirectionpages);
+ memcpy(ring_req->indirect_grefs, &cm->cm_indirectionrefs,
+ sizeof(grant_ref_t) * sc->xbd_max_request_indirectpages);
+ }
if (cm->cm_operation == BLKIF_OP_READ)
op = BUS_DMASYNC_PREREAD;
@@ -733,7 +761,7 @@ xbd_alloc_ring(struct xbd_softc *sc)
i++, sring_page_addr += PAGE_SIZE) {
error = xenbus_grant_ring(sc->xbd_dev,
- (vtomach(sring_page_addr) >> PAGE_SHIFT),
+ (vtophys(sring_page_addr) >> PAGE_SHIFT),
&sc->xbd_ring_ref[i]);
if (error) {
xenbus_dev_fatal(sc->xbd_dev, error,
@@ -1015,6 +1043,16 @@ xbd_free(struct xbd_softc *sc)
cm->cm_sg_refs = NULL;
}
+ if (cm->cm_indirectionpages != NULL) {
+ gnttab_end_foreign_access_references(
+ sc->xbd_max_request_indirectpages,
+ &cm->cm_indirectionrefs[0]);
+ contigfree(cm->cm_indirectionpages, PAGE_SIZE *
+ sc->xbd_max_request_indirectpages,
+ M_XENBLOCKFRONT);
+ cm->cm_indirectionpages = NULL;
+ }
+
bus_dmamap_destroy(sc->xbd_io_dmat, cm->cm_map);
}
free(sc->xbd_shadow, M_XENBLOCKFRONT);
@@ -1051,9 +1089,6 @@ xbd_initialize(struct xbd_softc *sc)
*/
max_ring_page_order = 0;
sc->xbd_ring_pages = 1;
- sc->xbd_max_request_segments = BLKIF_MAX_SEGMENTS_PER_REQUEST;
- sc->xbd_max_request_size =
- XBD_SEGS_TO_SIZE(sc->xbd_max_request_segments);
/*
* Protocol negotiation.
@@ -1167,7 +1202,7 @@ xbd_connect(struct xbd_softc *sc)
unsigned long sectors, sector_size;
unsigned int binfo;
int err, feature_barrier, feature_flush;
- int i;
+ int i, j;
if (sc->xbd_state == XBD_STATE_CONNECTED ||
sc->xbd_state == XBD_STATE_SUSPENDED)
@@ -1198,6 +1233,22 @@ xbd_connect(struct xbd_softc *sc)
if (err == 0 && feature_flush != 0)
sc->xbd_flags |= XBDF_FLUSH;
+ err = xs_gather(XST_NIL, xenbus_get_otherend_path(dev),
+ "feature-max-indirect-segments", "%" PRIu32,
+ &sc->xbd_max_request_segments, NULL);
+ if ((err != 0) || (xbd_enable_indirect == 0))
+ sc->xbd_max_request_segments = 0;
+ if (sc->xbd_max_request_segments > XBD_MAX_INDIRECT_SEGMENTS)
+ sc->xbd_max_request_segments = XBD_MAX_INDIRECT_SEGMENTS;
+ if (sc->xbd_max_request_segments > XBD_SIZE_TO_SEGS(MAXPHYS))
+ sc->xbd_max_request_segments = XBD_SIZE_TO_SEGS(MAXPHYS);
+ sc->xbd_max_request_indirectpages =
+ XBD_INDIRECT_SEGS_TO_PAGES(sc->xbd_max_request_segments);
+ if (sc->xbd_max_request_segments < BLKIF_MAX_SEGMENTS_PER_REQUEST)
+ sc->xbd_max_request_segments = BLKIF_MAX_SEGMENTS_PER_REQUEST;
+ sc->xbd_max_request_size =
+ XBD_SEGS_TO_SIZE(sc->xbd_max_request_segments);
+
/* Allocate datastructures based on negotiated values. */
err = bus_dma_tag_create(
bus_get_dma_tag(sc->xbd_dev), /* parent */
@@ -1230,6 +1281,7 @@ xbd_connect(struct xbd_softc *sc)
for (i = 0; i < sc->xbd_max_requests; i++) {
struct xbd_command *cm;
+ void * indirectpages;
cm = &sc->xbd_shadow[i];
cm->cm_sg_refs = malloc(
@@ -1242,6 +1294,24 @@ xbd_connect(struct xbd_softc *sc)
cm->cm_sc = sc;
if (bus_dmamap_create(sc->xbd_io_dmat, 0, &cm->cm_map) != 0)
break;
+ if (sc->xbd_max_request_indirectpages > 0) {
+ indirectpages = contigmalloc(
+ PAGE_SIZE * sc->xbd_max_request_indirectpages,
+ M_XENBLOCKFRONT, M_ZERO, 0, ~0, PAGE_SIZE, 0);
+ } else {
+ indirectpages = NULL;
+ }
+ for (j = 0; j < sc->xbd_max_request_indirectpages; j++) {
+ if (gnttab_grant_foreign_access(
+ xenbus_get_otherend_id(sc->xbd_dev),
+ (vtophys(indirectpages) >> PAGE_SHIFT) + j,
+ 1 /* grant read-only access */,
+ &cm->cm_indirectionrefs[j]))
+ break;
+ }
+ if (j < sc->xbd_max_request_indirectpages)
+ break;
+ cm->cm_indirectionpages = indirectpages;
xbd_free_command(cm);
}
@@ -1296,6 +1366,9 @@ xbd_probe(device_t dev)
if (strcmp(xenbus_get_type(dev), "vbd") != 0)
return (ENXIO);
+ if (xen_hvm_domain() && xen_disable_pv_disks != 0)
+ return (ENXIO);
+
if (xen_hvm_domain()) {
int error;
char *type;
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