summaryrefslogtreecommitdiffstats
path: root/drivers/block/xen-blkback
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/block/xen-blkback')
-rw-r--r--drivers/block/xen-blkback/blkback.c13
-rw-r--r--drivers/block/xen-blkback/common.h2
-rw-r--r--drivers/block/xen-blkback/xenbus.c89
3 files changed, 84 insertions, 20 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index bd2b3bbbb22c..9121a2c3e26f 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -84,6 +84,13 @@ MODULE_PARM_DESC(max_persistent_grants,
"Maximum number of grants to map persistently");
/*
+ * Maximum order of pages to be used for the shared ring between front and
+ * backend, 4KB page granularity is used.
+ */
+unsigned int xen_blkif_max_ring_order = XENBUS_MAX_RING_PAGE_ORDER;
+module_param_named(max_ring_page_order, xen_blkif_max_ring_order, int, S_IRUGO);
+MODULE_PARM_DESC(max_ring_page_order, "Maximum order of pages to be used for the shared ring");
+/*
* The LRU mechanism to clean the lists of persistent grants needs to
* be executed periodically. The time interval between consecutive executions
* of the purge mechanism is set in ms.
@@ -1451,6 +1458,12 @@ static int __init xen_blkif_init(void)
if (!xen_domain())
return -ENODEV;
+ if (xen_blkif_max_ring_order > XENBUS_MAX_RING_PAGE_ORDER) {
+ pr_info("Invalid max_ring_order (%d), will use default max: %d.\n",
+ xen_blkif_max_ring_order, XENBUS_MAX_RING_PAGE_ORDER);
+ xen_blkif_max_ring_order = XENBUS_MAX_RING_PAGE_ORDER;
+ }
+
rc = xen_blkif_interface_init();
if (rc)
goto failed_init;
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index 043f13b7b7b0..8ccc49d01c8e 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -44,6 +44,7 @@
#include <xen/interface/io/blkif.h>
#include <xen/interface/io/protocols.h>
+extern unsigned int xen_blkif_max_ring_order;
/*
* This is the maximum number of segments that would be allowed in indirect
* requests. This value will also be passed to the frontend.
@@ -320,6 +321,7 @@ struct xen_blkif {
struct work_struct free_work;
/* Thread shutdown wait queue. */
wait_queue_head_t shutdown_wq;
+ unsigned int nr_ring_pages;
};
struct seg_buf {
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index c212d41fd5bd..deb3f001791f 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -25,6 +25,7 @@
/* Enlarge the array size in order to fully show blkback name. */
#define BLKBACK_NAME_LEN (20)
+#define RINGREF_NAME_LEN (20)
struct backend_info {
struct xenbus_device *dev;
@@ -156,8 +157,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
return blkif;
}
-static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t gref,
- unsigned int evtchn)
+static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref,
+ unsigned int nr_grefs, unsigned int evtchn)
{
int err;
@@ -165,7 +166,7 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t gref,
if (blkif->irq)
return 0;
- err = xenbus_map_ring_valloc(blkif->be->dev, &gref, 1,
+ err = xenbus_map_ring_valloc(blkif->be->dev, gref, nr_grefs,
&blkif->blk_ring);
if (err < 0)
return err;
@@ -175,21 +176,21 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t gref,
{
struct blkif_sring *sring;
sring = (struct blkif_sring *)blkif->blk_ring;
- BACK_RING_INIT(&blkif->blk_rings.native, sring, PAGE_SIZE);
+ BACK_RING_INIT(&blkif->blk_rings.native, sring, PAGE_SIZE * nr_grefs);
break;
}
case BLKIF_PROTOCOL_X86_32:
{
struct blkif_x86_32_sring *sring_x86_32;
sring_x86_32 = (struct blkif_x86_32_sring *)blkif->blk_ring;
- BACK_RING_INIT(&blkif->blk_rings.x86_32, sring_x86_32, PAGE_SIZE);
+ BACK_RING_INIT(&blkif->blk_rings.x86_32, sring_x86_32, PAGE_SIZE * nr_grefs);
break;
}
case BLKIF_PROTOCOL_X86_64:
{
struct blkif_x86_64_sring *sring_x86_64;
sring_x86_64 = (struct blkif_x86_64_sring *)blkif->blk_ring;
- BACK_RING_INIT(&blkif->blk_rings.x86_64, sring_x86_64, PAGE_SIZE);
+ BACK_RING_INIT(&blkif->blk_rings.x86_64, sring_x86_64, PAGE_SIZE * nr_grefs);
break;
}
default:
@@ -270,7 +271,7 @@ static void xen_blkif_free(struct xen_blkif *blkif)
i++;
}
- WARN_ON(i != XEN_BLKIF_REQS_PER_PAGE);
+ WARN_ON(i != (XEN_BLKIF_REQS_PER_PAGE * blkif->nr_ring_pages));
kmem_cache_free(xen_blkif_cachep, blkif);
}
@@ -555,6 +556,11 @@ static int xen_blkbk_probe(struct xenbus_device *dev,
if (err)
goto fail;
+ err = xenbus_printf(XBT_NIL, dev->nodename, "max-ring-page-order", "%u",
+ xen_blkif_max_ring_order);
+ if (err)
+ pr_warn("%s write out 'max-ring-page-order' failed\n", __func__);
+
err = xenbus_switch_state(dev, XenbusStateInitWait);
if (err)
goto fail;
@@ -818,8 +824,8 @@ again:
static int connect_ring(struct backend_info *be)
{
struct xenbus_device *dev = be->dev;
- unsigned long ring_ref;
- unsigned int evtchn;
+ unsigned int ring_ref[XENBUS_MAX_RING_PAGES];
+ unsigned int evtchn, nr_grefs, ring_page_order;
unsigned int pers_grants;
char protocol[64] = "";
struct pending_req *req, *n;
@@ -827,14 +833,57 @@ static int connect_ring(struct backend_info *be)
pr_debug("%s %s\n", __func__, dev->otherend);
- err = xenbus_gather(XBT_NIL, dev->otherend, "ring-ref", "%lu",
- &ring_ref, "event-channel", "%u", &evtchn, NULL);
- if (err) {
- xenbus_dev_fatal(dev, err,
- "reading %s/ring-ref and event-channel",
+ err = xenbus_scanf(XBT_NIL, dev->otherend, "event-channel", "%u",
+ &evtchn);
+ if (err != 1) {
+ err = -EINVAL;
+ xenbus_dev_fatal(dev, err, "reading %s/event-channel",
dev->otherend);
return err;
}
+ pr_info("event-channel %u\n", evtchn);
+
+ err = xenbus_scanf(XBT_NIL, dev->otherend, "ring-page-order", "%u",
+ &ring_page_order);
+ if (err != 1) {
+ err = xenbus_scanf(XBT_NIL, dev->otherend, "ring-ref",
+ "%u", &ring_ref[0]);
+ if (err != 1) {
+ err = -EINVAL;
+ xenbus_dev_fatal(dev, err, "reading %s/ring-ref",
+ dev->otherend);
+ return err;
+ }
+ nr_grefs = 1;
+ pr_info("%s:using single page: ring-ref %d\n", dev->otherend,
+ ring_ref[0]);
+ } else {
+ unsigned int i;
+
+ if (ring_page_order > xen_blkif_max_ring_order) {
+ err = -EINVAL;
+ xenbus_dev_fatal(dev, err, "%s/request %d ring page order exceed max:%d",
+ dev->otherend, ring_page_order,
+ xen_blkif_max_ring_order);
+ return err;
+ }
+
+ nr_grefs = 1 << ring_page_order;
+ for (i = 0; i < nr_grefs; i++) {
+ char ring_ref_name[RINGREF_NAME_LEN];
+
+ snprintf(ring_ref_name, RINGREF_NAME_LEN, "ring-ref%u", i);
+ err = xenbus_scanf(XBT_NIL, dev->otherend, ring_ref_name,
+ "%u", &ring_ref[i]);
+ if (err != 1) {
+ err = -EINVAL;
+ xenbus_dev_fatal(dev, err, "reading %s/%s",
+ dev->otherend, ring_ref_name);
+ return err;
+ }
+ pr_info("ring-ref%u: %u\n", i, ring_ref[i]);
+ }
+ }
be->blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT;
err = xenbus_gather(XBT_NIL, dev->otherend, "protocol",
@@ -859,12 +908,13 @@ static int connect_ring(struct backend_info *be)
be->blkif->vbd.feature_gnt_persistent = pers_grants;
be->blkif->vbd.overflow_max_grants = 0;
+ be->blkif->nr_ring_pages = nr_grefs;
- pr_info("ring-ref %ld, event-channel %d, protocol %d (%s) %s\n",
- ring_ref, evtchn, be->blkif->blk_protocol, protocol,
+ pr_info("ring-pages:%d, event-channel %d, protocol %d (%s) %s\n",
+ nr_grefs, evtchn, be->blkif->blk_protocol, protocol,
pers_grants ? "persistent grants" : "");
- for (i = 0; i < XEN_BLKIF_REQS_PER_PAGE; i++) {
+ for (i = 0; i < nr_grefs * XEN_BLKIF_REQS_PER_PAGE; i++) {
req = kzalloc(sizeof(*req), GFP_KERNEL);
if (!req)
goto fail;
@@ -883,10 +933,9 @@ static int connect_ring(struct backend_info *be)
}
/* Map the shared frame, irq etc. */
- err = xen_blkif_map(be->blkif, ring_ref, evtchn);
+ err = xen_blkif_map(be->blkif, ring_ref, nr_grefs, evtchn);
if (err) {
- xenbus_dev_fatal(dev, err, "mapping ring-ref %lu port %u",
- ring_ref, evtchn);
+ xenbus_dev_fatal(dev, err, "mapping ring-ref port %u", evtchn);
return err;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-03 13:50:21 +0000