Author: royger
Date: Fri Jun 12 07:50:34 2015
New Revision: 284296
URL: https://svnweb.freebsd.org/changeset/base/284296
Log:
xen-blk{front/back}: remove broken FreeBSD extensions
The FreeBSD extension adds a new request type, called blkif_segment_block
which has a size of 112bytes for both i386 and amd64. This is fine on
amd64, since requests have a size of 112B there also. But this is not true
for i386, where requests have a size of 108B. So on i386 we basically
overrun the ring slot when queuing a request of type blkif_segment_block_t,
which is very bad.
Remove this extension (including a cleanup of the public blkif.h header
file) from blkfront and blkback.
Sponsored by: Citrix Systems R&D
Tested-by: cperciva
Modified:
head/sys/dev/xen/blkback/blkback.c
head/sys/dev/xen/blkfront/blkfront.c
head/sys/dev/xen/blkfront/block.h
head/sys/xen/blkif.h
head/sys/xen/interface/io/blkif.h
Modified: head/sys/dev/xen/blkback/blkback.c
==============================================================================
--- head/sys/dev/xen/blkback/blkback.c Fri Jun 12 07:23:55 2015
(r284295)
+++ head/sys/dev/xen/blkback/blkback.c Fri Jun 12 07:50:34 2015
(r284296)
@@ -85,11 +85,19 @@ __FBSDID("$FreeBSD$");
/*--------------------------- Compile-time Tunables
--------------------------*/
/**
+ * The maximum number of shared memory ring pages we will allow in a
+ * negotiated block-front/back communication channel. Allow enough
+ * ring space for all requests to be XBB_MAX_REQUEST_SIZE'd.
+ */
+#define XBB_MAX_RING_PAGES 32
+
+/**
* The maximum number of outstanding request blocks (request headers plus
* additional segment blocks) we will allow in a negotiated block-front/back
* communication channel.
*/
-#define XBB_MAX_REQUESTS 256
+#define XBB_MAX_REQUESTS \
+ __CONST_RING_SIZE(blkif, PAGE_SIZE * XBB_MAX_RING_PAGES)
/**
* \brief Define to force all I/O to be performed on memory owned by the
@@ -148,14 +156,6 @@ static MALLOC_DEFINE(M_XENBLOCKBACK, "xb
(XBB_MAX_REQUEST_SIZE / PAGE_SIZE) + 1)))
/**
- * The maximum number of shared memory ring pages we will allow in a
- * negotiated block-front/back communication channel. Allow enough
- * ring space for all requests to be XBB_MAX_REQUEST_SIZE'd.
- */
-#define XBB_MAX_RING_PAGES
\
- BLKIF_RING_PAGES(BLKIF_SEGS_TO_BLOCKS(XBB_MAX_SEGMENTS_PER_REQUEST) \
- * XBB_MAX_REQUESTS)
-/**
* The maximum number of ring pages that we can allow per request list.
* We limit this to the maximum number of segments per request, because
* that is already a reasonable number of segments to aggregate. This
@@ -1328,7 +1328,7 @@ xbb_queue_response(struct xbb_softc *xbb
if (status != BLKIF_RSP_OKAY)
xbb->reqs_completed_with_error++;
- xbb->rings.common.rsp_prod_pvt += BLKIF_SEGS_TO_BLOCKS(req->nr_pages);
+ xbb->rings.common.rsp_prod_pvt++;
xbb->reqs_queued_for_completion++;
@@ -1666,87 +1666,49 @@ xbb_dispatch_io(struct xbb_softc *xbb, s
goto send_response;
}
- block_segs = MIN(nreq->nr_pages,
- BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK);
+ block_segs = nseg;
sg = ring_req->seg;
last_block_sg = sg + block_segs;
- while (1) {
- while (sg < last_block_sg) {
- KASSERT(seg_idx <
- XBB_MAX_SEGMENTS_PER_REQLIST,
- ("seg_idx %d is too large, max "
- "segs %d\n", seg_idx,
- XBB_MAX_SEGMENTS_PER_REQLIST));
-
- xbb_sg->first_sect = sg->first_sect;
- xbb_sg->last_sect = sg->last_sect;
- xbb_sg->nsect =
- (int8_t)(sg->last_sect -
- sg->first_sect + 1);
-
- if ((sg->last_sect >= (PAGE_SIZE >> 9))
- || (xbb_sg->nsect <= 0)) {
- reqlist->status = BLKIF_RSP_ERROR;
- goto send_response;
- }
-
- nr_sects += xbb_sg->nsect;
- map->host_addr = xbb_get_gntaddr(reqlist,
- seg_idx, /*sector*/0);
- KASSERT(map->host_addr + PAGE_SIZE <=
- xbb->ring_config.gnt_addr,
- ("Host address %#jx len %d overlaps "
- "ring address %#jx\n",
- (uintmax_t)map->host_addr, PAGE_SIZE,
- (uintmax_t)xbb->ring_config.gnt_addr));
-
- map->flags = GNTMAP_host_map;
- map->ref = sg->gref;
- map->dom = xbb->otherend_id;
- if (operation == BIO_WRITE)
- map->flags |= GNTMAP_readonly;
- sg++;
- map++;
- xbb_sg++;
- seg_idx++;
- req_seg_idx++;
+ while (sg < last_block_sg) {
+ KASSERT(seg_idx <
+ XBB_MAX_SEGMENTS_PER_REQLIST,
+ ("seg_idx %d is too large, max "
+ "segs %d\n", seg_idx,
+ XBB_MAX_SEGMENTS_PER_REQLIST));
+
+ xbb_sg->first_sect = sg->first_sect;
+ xbb_sg->last_sect = sg->last_sect;
+ xbb_sg->nsect =
+ (int8_t)(sg->last_sect -
+ sg->first_sect + 1);
+
+ if ((sg->last_sect >= (PAGE_SIZE >> 9))
+ || (xbb_sg->nsect <= 0)) {
+ reqlist->status = BLKIF_RSP_ERROR;
+ goto send_response;
}
- block_segs = MIN(nseg - req_seg_idx,
- BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK);
- if (block_segs == 0)
- break;
-
- /*
- * Fetch the next request block full of SG elements.
- * For now, only the spacing between entries is
- * different in the different ABIs, not the sg entry
- * layout.
- */
- req_ring_idx++;
- switch (xbb->abi) {
- case BLKIF_PROTOCOL_NATIVE:
- sg = BLKRING_GET_SEG_BLOCK(&xbb->rings.native,
- req_ring_idx);
- break;
- case BLKIF_PROTOCOL_X86_32:
- {
- sg = BLKRING_GET_SEG_BLOCK(&xbb->rings.x86_32,
- req_ring_idx);
- break;
- }
- case BLKIF_PROTOCOL_X86_64:
- {
- sg = BLKRING_GET_SEG_BLOCK(&xbb->rings.x86_64,
- req_ring_idx);
- break;
- }
- default:
- panic("Unexpected blkif protocol ABI.");
- /* NOTREACHED */
- }
- last_block_sg = sg + block_segs;
+ nr_sects += xbb_sg->nsect;
+ map->host_addr = xbb_get_gntaddr(reqlist,
+ seg_idx, /*sector*/0);
+ KASSERT(map->host_addr + PAGE_SIZE <=
+ xbb->ring_config.gnt_addr,
+ ("Host address %#jx len %d overlaps "
+ "ring address %#jx\n",
+ (uintmax_t)map->host_addr, PAGE_SIZE,
+ (uintmax_t)xbb->ring_config.gnt_addr));
+
+ map->flags = GNTMAP_host_map;
+ map->ref = sg->gref;
+ map->dom = xbb->otherend_id;
+ if (operation == BIO_WRITE)
+ map->flags |= GNTMAP_readonly;
+ sg++;
+ map++;
+ xbb_sg++;
+ seg_idx++;
+ req_seg_idx++;
}
/* Convert to the disk's sector size */
@@ -2000,8 +1962,7 @@ xbb_run_queue(void *context, int pending
* response be generated before we make room in
* the queue for that response.
*/
- xbb->rings.common.req_cons +=
- BLKIF_SEGS_TO_BLOCKS(ring_req->nr_segments);
+ xbb->rings.common.req_cons++;
xbb->reqs_received++;
cur_size = xbb_count_sects(ring_req);
@@ -3091,7 +3052,7 @@ xbb_collect_frontend_info(struct xbb_sof
* Protocol defaults valid even if all negotiation fails.
*/
xbb->ring_config.ring_pages = 1;
- xbb->max_request_segments = BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK;
+ xbb->max_request_segments = BLKIF_MAX_SEGMENTS_PER_REQUEST;
xbb->max_request_size = xbb->max_request_segments * PAGE_SIZE;
/*
@@ -3122,60 +3083,23 @@ xbb_collect_frontend_info(struct xbb_sof
* fields.
*/
ring_page_order = 0;
+ xbb->max_requests = 32;
+
(void)xs_scanf(XST_NIL, otherend_path,
"ring-page-order", NULL, "%u",
&ring_page_order);
xbb->ring_config.ring_pages = 1 << ring_page_order;
- (void)xs_scanf(XST_NIL, otherend_path,
- "num-ring-pages", NULL, "%u",
- &xbb->ring_config.ring_pages);
ring_size = PAGE_SIZE * xbb->ring_config.ring_pages;
xbb->max_requests = BLKIF_MAX_RING_REQUESTS(ring_size);
- (void)xs_scanf(XST_NIL, otherend_path,
- "max-requests", NULL, "%u",
- &xbb->max_requests);
-
- (void)xs_scanf(XST_NIL, otherend_path,
- "max-request-segments", NULL, "%u",
- &xbb->max_request_segments);
-
- (void)xs_scanf(XST_NIL, otherend_path,
- "max-request-size", NULL, "%u",
- &xbb->max_request_size);
-
if (xbb->ring_config.ring_pages > XBB_MAX_RING_PAGES) {
xenbus_dev_fatal(xbb->dev, EINVAL,
"Front-end specified ring-pages of %u "
- "exceeds backend limit of %zu. "
+ "exceeds backend limit of %u. "
"Unable to connect.",
xbb->ring_config.ring_pages,
XBB_MAX_RING_PAGES);
return (EINVAL);
- } else if (xbb->max_requests > XBB_MAX_REQUESTS) {
- xenbus_dev_fatal(xbb->dev, EINVAL,
- "Front-end specified max_requests of %u "
- "exceeds backend limit of %u. "
- "Unable to connect.",
- xbb->max_requests,
- XBB_MAX_REQUESTS);
- return (EINVAL);
- } else if (xbb->max_request_segments > XBB_MAX_SEGMENTS_PER_REQUEST) {
- xenbus_dev_fatal(xbb->dev, EINVAL,
- "Front-end specified max_requests_segments "
- "of %u exceeds backend limit of %u. "
- "Unable to connect.",
- xbb->max_request_segments,
- XBB_MAX_SEGMENTS_PER_REQUEST);
- return (EINVAL);
- } else if (xbb->max_request_size > XBB_MAX_REQUEST_SIZE) {
- xenbus_dev_fatal(xbb->dev, EINVAL,
- "Front-end specified max_request_size "
- "of %u exceeds backend limit of %u. "
- "Unable to connect.",
- xbb->max_request_size,
- XBB_MAX_REQUEST_SIZE);
- return (EINVAL);
}
if (xbb->ring_config.ring_pages == 1) {
@@ -3723,18 +3647,6 @@ xbb_attach(device_t dev)
return (error);
}
- /*
- * Amazon EC2 client compatility. They refer to max-ring-pages
- * instead of to max-ring-page-order.
- */
- error = xs_printf(XST_NIL, xenbus_get_node(xbb->dev),
- "max-ring-pages", "%zu", XBB_MAX_RING_PAGES);
- if (error) {
- xbb_attach_failed(xbb, error, "writing %s/max-ring-pages",
- xenbus_get_node(xbb->dev));
- return (error);
- }
-
max_ring_page_order = flsl(XBB_MAX_RING_PAGES) - 1;
error = xs_printf(XST_NIL, xenbus_get_node(xbb->dev),
"max-ring-page-order", "%u", max_ring_page_order);
@@ -3744,32 +3656,6 @@ xbb_attach(device_t dev)
return (error);
}
- error = xs_printf(XST_NIL, xenbus_get_node(xbb->dev),
- "max-requests", "%u", XBB_MAX_REQUESTS);
- if (error) {
- xbb_attach_failed(xbb, error, "writing %s/max-requests",
- xenbus_get_node(xbb->dev));
- return (error);
- }
-
- error = xs_printf(XST_NIL, xenbus_get_node(xbb->dev),
- "max-request-segments", "%u",
- XBB_MAX_SEGMENTS_PER_REQUEST);
- if (error) {
- xbb_attach_failed(xbb, error, "writing %s/max-request-segments",
- xenbus_get_node(xbb->dev));
- return (error);
- }
-
- error = xs_printf(XST_NIL, xenbus_get_node(xbb->dev),
- "max-request-size", "%u",
- XBB_MAX_REQUEST_SIZE);
- if (error) {
- xbb_attach_failed(xbb, error, "writing %s/max-request-size",
- xenbus_get_node(xbb->dev));
- return (error);
- }
-
/* Collect physical device information. */
error = xs_gather(XST_NIL, xenbus_get_otherend_path(xbb->dev),
"device-type", NULL, &xbb->dev_type,
Modified: head/sys/dev/xen/blkfront/blkfront.c
==============================================================================
--- head/sys/dev/xen/blkfront/blkfront.c Fri Jun 12 07:23:55 2015
(r284295)
+++ head/sys/dev/xen/blkfront/blkfront.c Fri Jun 12 07:50:34 2015
(r284296)
@@ -174,7 +174,6 @@ xbd_queue_cb(void *arg, bus_dma_segment_
sc = cm->cm_sc;
if (error) {
- printf("error %d in xbd_queue_cb\n", error);
cm->cm_bp->bio_error = EIO;
biodone(cm->cm_bp);
xbd_free_command(cm);
@@ -191,55 +190,44 @@ xbd_queue_cb(void *arg, bus_dma_segment_
ring_req->nr_segments = nsegs;
cm->cm_nseg = nsegs;
- block_segs = MIN(nsegs, BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK);
+ block_segs = MIN(nsegs, BLKIF_MAX_SEGMENTS_PER_REQUEST);
sg = ring_req->seg;
last_block_sg = sg + block_segs;
sg_ref = cm->cm_sg_refs;
- while (1) {
+ while (sg < last_block_sg) {
+ buffer_ma = segs->ds_addr;
+ fsect = (buffer_ma & PAGE_MASK) >> XBD_SECTOR_SHFT;
+ lsect = fsect + (segs->ds_len >> XBD_SECTOR_SHFT) - 1;
- while (sg < last_block_sg) {
- buffer_ma = segs->ds_addr;
- fsect = (buffer_ma & PAGE_MASK) >> XBD_SECTOR_SHFT;
- lsect = fsect + (segs->ds_len >> XBD_SECTOR_SHFT) - 1;
+ KASSERT(lsect <= 7, ("XEN disk driver data cannot "
+ "cross a page boundary"));
- KASSERT(lsect <= 7, ("XEN disk driver data cannot "
- "cross a page boundary"));
+ /* install a grant reference. */
+ ref = gnttab_claim_grant_reference(&cm->cm_gref_head);
- /* install a grant reference. */
- ref = gnttab_claim_grant_reference(&cm->cm_gref_head);
-
- /*
- * GNTTAB_LIST_END == 0xffffffff, but it is private
- * to gnttab.c.
- */
- KASSERT(ref != ~0, ("grant_reference failed"));
-
- gnttab_grant_foreign_access_ref(
- ref,
- xenbus_get_otherend_id(sc->xbd_dev),
- buffer_ma >> PAGE_SHIFT,
- ring_req->operation == BLKIF_OP_WRITE);
-
- *sg_ref = ref;
- *sg = (struct blkif_request_segment) {
- .gref = ref,
- .first_sect = fsect,
- .last_sect = lsect
- };
- sg++;
- sg_ref++;
- segs++;
- nsegs--;
- }
- block_segs = MIN(nsegs, BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK);
- if (block_segs == 0)
- break;
+ /*
+ * GNTTAB_LIST_END == 0xffffffff, but it is private
+ * to gnttab.c.
+ */
+ KASSERT(ref != ~0, ("grant_reference failed"));
- sg = BLKRING_GET_SEG_BLOCK(&sc->xbd_ring,
- sc->xbd_ring.req_prod_pvt);
- sc->xbd_ring.req_prod_pvt++;
- last_block_sg = sg + block_segs;
+ gnttab_grant_foreign_access_ref(
+ ref,
+ xenbus_get_otherend_id(sc->xbd_dev),
+ buffer_ma >> PAGE_SHIFT,
+ ring_req->operation == BLKIF_OP_WRITE);
+
+ *sg_ref = ref;
+ *sg = (struct blkif_request_segment) {
+ .gref = ref,
+ .first_sect = fsect,
+ .last_sect = lsect
+ };
+ sg++;
+ sg_ref++;
+ segs++;
+ nsegs--;
}
if (cm->cm_operation == BLKIF_OP_READ)
@@ -396,8 +384,8 @@ xbd_startio(struct xbd_softc *sc)
if (sc->xbd_state != XBD_STATE_CONNECTED)
return;
- while (RING_FREE_REQUESTS(&sc->xbd_ring) >=
- sc->xbd_max_request_blocks) {
+ while (!RING_FULL(&sc->xbd_ring)) {
+
if (sc->xbd_qfrozen_cnt != 0)
break;
@@ -450,13 +438,6 @@ xbd_bio_complete(struct xbd_softc *sc, s
biodone(bp);
}
-static int
-xbd_completion(struct xbd_command *cm)
-{
- gnttab_end_foreign_access_references(cm->cm_nseg, cm->cm_sg_refs);
- return (BLKIF_SEGS_TO_BLOCKS(cm->cm_nseg));
-}
-
static void
xbd_int(void *xsc)
{
@@ -482,7 +463,9 @@ xbd_int(void *xsc)
cm = &sc->xbd_shadow[bret->id];
xbd_remove_cm(cm, XBD_Q_BUSY);
- i += xbd_completion(cm);
+ gnttab_end_foreign_access_references(cm->cm_nseg,
+ cm->cm_sg_refs);
+ i++;
if (cm->cm_operation == BLKIF_OP_READ)
op = BUS_DMASYNC_POSTREAD;
@@ -1064,11 +1047,9 @@ 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_HEADER_BLOCK;
+ sc->xbd_max_request_segments = BLKIF_MAX_SEGMENTS_PER_REQUEST;
sc->xbd_max_request_size =
XBD_SEGS_TO_SIZE(sc->xbd_max_request_segments);
- sc->xbd_max_request_blocks =
- BLKIF_SEGS_TO_BLOCKS(sc->xbd_max_request_segments);
/*
* Protocol negotiation.
@@ -1095,24 +1076,10 @@ xbd_initialize(struct xbd_softc *sc)
if (sc->xbd_ring_pages < 1)
sc->xbd_ring_pages = 1;
- sc->xbd_max_requests =
- BLKIF_MAX_RING_REQUESTS(sc->xbd_ring_pages * PAGE_SIZE);
- (void)xs_scanf(XST_NIL, otherend_path,
- "max-requests", NULL, "%" PRIu32,
- &sc->xbd_max_requests);
-
- (void)xs_scanf(XST_NIL, otherend_path,
- "max-request-segments", NULL, "%" PRIu32,
- &sc->xbd_max_request_segments);
-
- (void)xs_scanf(XST_NIL, otherend_path,
- "max-request-size", NULL, "%" PRIu32,
- &sc->xbd_max_request_size);
-
if (sc->xbd_ring_pages > XBD_MAX_RING_PAGES) {
device_printf(sc->xbd_dev,
"Back-end specified ring-pages of %u "
- "limited to front-end limit of %zu.\n",
+ "limited to front-end limit of %u.\n",
sc->xbd_ring_pages, XBD_MAX_RING_PAGES);
sc->xbd_ring_pages = XBD_MAX_RING_PAGES;
}
@@ -1128,46 +1095,16 @@ xbd_initialize(struct xbd_softc *sc)
sc->xbd_ring_pages = new_page_limit;
}
+ sc->xbd_max_requests =
+ BLKIF_MAX_RING_REQUESTS(sc->xbd_ring_pages * PAGE_SIZE);
if (sc->xbd_max_requests > XBD_MAX_REQUESTS) {
device_printf(sc->xbd_dev,
"Back-end specified max_requests of %u "
- "limited to front-end limit of %u.\n",
+ "limited to front-end limit of %zu.\n",
sc->xbd_max_requests, XBD_MAX_REQUESTS);
sc->xbd_max_requests = XBD_MAX_REQUESTS;
}
- if (sc->xbd_max_request_segments > XBD_MAX_SEGMENTS_PER_REQUEST) {
- device_printf(sc->xbd_dev,
- "Back-end specified max_request_segments of %u "
- "limited to front-end limit of %u.\n",
- sc->xbd_max_request_segments,
- XBD_MAX_SEGMENTS_PER_REQUEST);
- sc->xbd_max_request_segments = XBD_MAX_SEGMENTS_PER_REQUEST;
- }
-
- if (sc->xbd_max_request_size > XBD_MAX_REQUEST_SIZE) {
- device_printf(sc->xbd_dev,
- "Back-end specified max_request_size of %u "
- "limited to front-end limit of %u.\n",
- sc->xbd_max_request_size,
- XBD_MAX_REQUEST_SIZE);
- sc->xbd_max_request_size = XBD_MAX_REQUEST_SIZE;
- }
-
- if (sc->xbd_max_request_size >
- XBD_SEGS_TO_SIZE(sc->xbd_max_request_segments)) {
- device_printf(sc->xbd_dev,
- "Back-end specified max_request_size of %u "
- "limited to front-end limit of %u. (Too few segments.)\n",
- sc->xbd_max_request_size,
- XBD_SEGS_TO_SIZE(sc->xbd_max_request_segments));
- sc->xbd_max_request_size =
- XBD_SEGS_TO_SIZE(sc->xbd_max_request_segments);
- }
-
- sc->xbd_max_request_blocks =
- BLKIF_SEGS_TO_BLOCKS(sc->xbd_max_request_segments);
-
/* Allocate datastructures based on negotiated values. */
error = bus_dma_tag_create(
bus_get_dma_tag(sc->xbd_dev), /* parent */
@@ -1241,36 +1178,6 @@ xbd_initialize(struct xbd_softc *sc)
}
}
- error = xs_printf(XST_NIL, node_path,
- "max-requests","%u",
- sc->xbd_max_requests);
- if (error) {
- xenbus_dev_fatal(sc->xbd_dev, error,
- "writing %s/max-requests",
- node_path);
- return;
- }
-
- error = xs_printf(XST_NIL, node_path,
- "max-request-segments","%u",
- sc->xbd_max_request_segments);
- if (error) {
- xenbus_dev_fatal(sc->xbd_dev, error,
- "writing %s/max-request-segments",
- node_path);
- return;
- }
-
- error = xs_printf(XST_NIL, node_path,
- "max-request-size","%u",
- sc->xbd_max_request_size);
- if (error) {
- xenbus_dev_fatal(sc->xbd_dev, error,
- "writing %s/max-request-size",
- node_path);
- return;
- }
-
error = xs_printf(XST_NIL, node_path, "event-channel",
"%u", xen_intr_port(sc->xen_intr_handle));
if (error) {
Modified: head/sys/dev/xen/blkfront/block.h
==============================================================================
--- head/sys/dev/xen/blkfront/block.h Fri Jun 12 07:23:55 2015
(r284295)
+++ head/sys/dev/xen/blkfront/block.h Fri Jun 12 07:50:34 2015
(r284296)
@@ -61,11 +61,19 @@
((size / PAGE_SIZE) + 1)
/**
+ * The maximum number of shared memory ring pages we will allow in a
+ * negotiated block-front/back communication channel. Allow enough
+ * ring space for all requests to be XBD_MAX_REQUEST_SIZE'd.
+ */
+#define XBD_MAX_RING_PAGES 32
+
+/**
* The maximum number of outstanding requests blocks (request headers plus
* additional segment blocks) we will allow in a negotiated block-front/back
* communication channel.
*/
-#define XBD_MAX_REQUESTS 256
+#define XBD_MAX_REQUESTS \
+ __CONST_RING_SIZE(blkif, PAGE_SIZE * XBD_MAX_RING_PAGES)
/**
* The maximum mapped region size per request we will allow in a negotiated
@@ -83,15 +91,6 @@
(MIN(BLKIF_MAX_SEGMENTS_PER_REQUEST, \
XBD_SIZE_TO_SEGS(XBD_MAX_REQUEST_SIZE)))
-/**
- * The maximum number of shared memory ring pages we will allow in a
- * negotiated block-front/back communication channel. Allow enough
- * ring space for all requests to be XBD_MAX_REQUEST_SIZE'd.
- */
-#define XBD_MAX_RING_PAGES \
- BLKIF_RING_PAGES(BLKIF_SEGS_TO_BLOCKS(XBD_MAX_SEGMENTS_PER_REQUEST) \
- * XBD_MAX_REQUESTS)
-
typedef enum {
XBDCF_Q_MASK = 0xFF,
/* This command has contributed to xbd_qfrozen_cnt. */
@@ -175,7 +174,6 @@ struct xbd_softc {
u_int xbd_ring_pages;
uint32_t xbd_max_requests;
uint32_t xbd_max_request_segments;
- uint32_t xbd_max_request_blocks;
uint32_t xbd_max_request_size;
grant_ref_t xbd_ring_ref[XBD_MAX_RING_PAGES];
blkif_front_ring_t xbd_ring;
Modified: head/sys/xen/blkif.h
==============================================================================
--- head/sys/xen/blkif.h Fri Jun 12 07:23:55 2015 (r284295)
+++ head/sys/xen/blkif.h Fri Jun 12 07:50:34 2015 (r284296)
@@ -46,7 +46,7 @@ struct blkif_x86_32_request {
blkif_vdev_t handle; /* only for read/write requests */
uint64_t id; /* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
- struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK];
+ struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
struct blkif_x86_32_response {
uint64_t id; /* copied from request */
@@ -64,7 +64,7 @@ struct blkif_x86_64_request {
blkif_vdev_t handle; /* only for read/write requests */
uint64_t __attribute__((__aligned__(8))) id;
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
- struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK];
+ struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
struct blkif_x86_64_response {
uint64_t __attribute__((__aligned__(8))) id;
@@ -114,7 +114,7 @@ enum blkif_protocol {
static void inline blkif_get_x86_32_req(blkif_request_t *dst,
blkif_x86_32_request_t *src)
{
- int i, n = BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK;
+ int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST;
dst->operation = src->operation;
dst->nr_segments = src->nr_segments;
dst->handle = src->handle;
@@ -129,7 +129,7 @@ static void inline blkif_get_x86_32_req(
static void inline blkif_get_x86_64_req(blkif_request_t *dst,
blkif_x86_64_request_t *src)
{
- int i, n = BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK;
+ int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST;
dst->operation = src->operation;
dst->nr_segments = src->nr_segments;
dst->handle = src->handle;
Modified: head/sys/xen/interface/io/blkif.h
==============================================================================
--- head/sys/xen/interface/io/blkif.h Fri Jun 12 07:23:55 2015
(r284295)
+++ head/sys/xen/interface/io/blkif.h Fri Jun 12 07:50:34 2015
(r284296)
@@ -457,21 +457,9 @@
#define BLKIF_OP_DISCARD 5
/*
- * Maximum scatter/gather segments associated with a request header block.
- * This is carefully chosen so that sizeof(blkif_ring_t) <= PAGE_SIZE.
- * NB. This could be 12 if the ring indexes weren't stored in the same page.
- */
-#define BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK 11
-
-/*
- * Maximum scatter/gather segments associated with a segment block.
- */
-#define BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK 14
-
-/*
* Maximum scatter/gather segments per request (header + segment blocks).
*/
-#define BLKIF_MAX_SEGMENTS_PER_REQUEST 255
+#define BLKIF_MAX_SEGMENTS_PER_REQUEST 11
/*
* NB. first_sect and last_sect in blkif_request_segment, as well as
@@ -512,22 +500,11 @@ struct blkif_request {
blkif_vdev_t handle; /* only for read/write requests */
uint64_t id; /* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
- blkif_request_segment_t seg[BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK];
+ blkif_request_segment_t seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
typedef struct blkif_request blkif_request_t;
/*
- * A segment block is a ring request structure that contains only
- * segment data.
- *
- * sizeof(struct blkif_segment_block) <= sizeof(struct blkif_request)
- */
-struct blkif_segment_block {
- blkif_request_segment_t seg[BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK];
-};
-typedef struct blkif_segment_block blkif_segment_block_t;
-
-/*
* Cast to this structure when blkif_request.operation == BLKIF_OP_DISCARD
* sizeof(struct blkif_request_discard) <= sizeof(struct blkif_request)
*/
@@ -564,21 +541,6 @@ typedef struct blkif_response blkif_resp
*/
DEFINE_RING_TYPES(blkif, struct blkif_request, struct blkif_response);
-/*
- * Index to, and treat as a segment block, an entry in the ring.
- */
-#define BLKRING_GET_SEG_BLOCK(_r, _idx) \
- (((blkif_segment_block_t *)RING_GET_REQUEST(_r, _idx))->seg)
-
-/*
- * The number of ring request blocks required to handle an I/O
- * request containing _segs segments.
- */
-#define BLKIF_SEGS_TO_BLOCKS(_segs) \
- ((((_segs - BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK) \
- + (BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK - 1)) \
- / BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK) + /*header_block*/1)
-
#define VDISK_CDROM 0x1
#define VDISK_REMOVABLE 0x2
#define VDISK_READONLY 0x4
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