Merge remote-tracking branch 'remotes/aperard/tags/pull-xen-20190624' into staging

Xen queue

* Fix build
* xen-block: support feature-large-sector-size
* xen-block: Support IOThread polling for PV shared rings
* Avoid usage of a VLA
* Cleanup Xen headers usage

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# gpg: Good signature from "Anthony PERARD <anthony.perard@gmail.com>" [marginal]
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* remotes/aperard/tags/pull-xen-20190624:
  xen: Import other xen/io/*.h
  Revert xen/io/ring.h of "Clean up a few header guard symbols"
  xen: Drop includes of xen/hvm/params.h
  xen: Avoid VLA
  xen-bus / xen-block: add support for event channel polling
  xen-bus: allow AioContext to be specified for each event channel
  xen-bus: use a separate fd for each event channel
  xen-block: support feature-large-sector-size

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 52 insertions, 38 deletions

diff --git a/hw/block/dataplane/xen-block.c b/hw/block/dataplane/xen-block.c
index f7ad452..0f200c5 100644
--- a/hw/block/dataplane/xen-block.c
+++ b/hw/block/dataplane/xen-block.c
@@ -58,6 +58,7 @@ struct XenBlockDataPlane {
     int requests_inflight;
     unsigned int max_requests;
     BlockBackend *blk;
+    unsigned int sector_size;
     QEMUBH *bh;
     IOThread *iothread;
     AioContext *ctx;
@@ -167,7 +168,7 @@ static int xen_block_parse_request(XenBlockRequest *request)
         goto err;
     }
 
-    request->start = request->req.sector_number * XEN_BLKIF_SECTOR_SIZE;
+    request->start = request->req.sector_number * dataplane->sector_size;
     for (i = 0; i < request->req.nr_segments; i++) {
         if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
             error_report("error: nr_segments too big");
@@ -177,14 +178,14 @@ static int xen_block_parse_request(XenBlockRequest *request)
             error_report("error: first > last sector");
             goto err;
         }
-        if (request->req.seg[i].last_sect * XEN_BLKIF_SECTOR_SIZE >=
+        if (request->req.seg[i].last_sect * dataplane->sector_size >=
             XC_PAGE_SIZE) {
             error_report("error: page crossing");
             goto err;
         }
 
         len = (request->req.seg[i].last_sect -
-               request->req.seg[i].first_sect + 1) * XEN_BLKIF_SECTOR_SIZE;
+               request->req.seg[i].first_sect + 1) * dataplane->sector_size;
         request->size += len;
     }
     if (request->start + request->size > blk_getlength(dataplane->blk)) {
@@ -218,17 +219,17 @@ static int xen_block_copy_request(XenBlockRequest *request)
         if (to_domain) {
             segs[i].dest.foreign.ref = request->req.seg[i].gref;
             segs[i].dest.foreign.offset = request->req.seg[i].first_sect *
-                XEN_BLKIF_SECTOR_SIZE;
+                dataplane->sector_size;
             segs[i].source.virt = virt;
         } else {
             segs[i].source.foreign.ref = request->req.seg[i].gref;
             segs[i].source.foreign.offset = request->req.seg[i].first_sect *
-                XEN_BLKIF_SECTOR_SIZE;
+                dataplane->sector_size;
             segs[i].dest.virt = virt;
         }
         segs[i].len = (request->req.seg[i].last_sect -
                        request->req.seg[i].first_sect + 1) *
-                      XEN_BLKIF_SECTOR_SIZE;
+                      dataplane->sector_size;
         virt += segs[i].len;
     }
 
@@ -317,7 +318,9 @@ static void xen_block_complete_aio(void *opaque, int ret)
     }
     xen_block_release_request(request);
 
-    qemu_bh_schedule(dataplane->bh);
+    if (dataplane->more_work) {
+        qemu_bh_schedule(dataplane->bh);
+    }
 
 done:
     aio_context_release(dataplane->ctx);
@@ -336,12 +339,12 @@ static bool xen_block_split_discard(XenBlockRequest *request,
 
     /* Wrap around, or overflowing byte limit? */
     if (sec_start + sec_count < sec_count ||
-        sec_start + sec_count > INT64_MAX / XEN_BLKIF_SECTOR_SIZE) {
+        sec_start + sec_count > INT64_MAX / dataplane->sector_size) {
         return false;
     }
 
-    byte_offset = sec_start * XEN_BLKIF_SECTOR_SIZE;
-    byte_remaining = sec_count * XEN_BLKIF_SECTOR_SIZE;
+    byte_offset = sec_start * dataplane->sector_size;
+    byte_remaining = sec_count * dataplane->sector_size;
 
     do {
         byte_chunk = byte_remaining > BDRV_REQUEST_MAX_BYTES ?
@@ -514,12 +517,13 @@ static int xen_block_get_request(XenBlockDataPlane *dataplane,
  */
 #define IO_PLUG_THRESHOLD 1
 
-static void xen_block_handle_requests(XenBlockDataPlane *dataplane)
+static bool xen_block_handle_requests(XenBlockDataPlane *dataplane)
 {
     RING_IDX rc, rp;
     XenBlockRequest *request;
     int inflight_atstart = dataplane->requests_inflight;
     int batched = 0;
+    bool done_something = false;
 
     dataplane->more_work = 0;
 
@@ -551,6 +555,7 @@ static void xen_block_handle_requests(XenBlockDataPlane *dataplane)
         }
         xen_block_get_request(dataplane, request, rc);
         dataplane->rings.common.req_cons = ++rc;
+        done_something = true;
 
         /* parse them */
         if (xen_block_parse_request(request) != 0) {
@@ -602,10 +607,7 @@ static void xen_block_handle_requests(XenBlockDataPlane *dataplane)
         blk_io_unplug(dataplane->blk);
     }
 
-    if (dataplane->more_work &&
-        dataplane->requests_inflight < dataplane->max_requests) {
-        qemu_bh_schedule(dataplane->bh);
-    }
+    return done_something;
 }
 
 static void xen_block_dataplane_bh(void *opaque)
@@ -617,21 +619,23 @@ static void xen_block_dataplane_bh(void *opaque)
     aio_context_release(dataplane->ctx);
 }
 
-static void xen_block_dataplane_event(void *opaque)
+static bool xen_block_dataplane_event(void *opaque)
 {
     XenBlockDataPlane *dataplane = opaque;
 
-    qemu_bh_schedule(dataplane->bh);
+    return xen_block_handle_requests(dataplane);
 }
 
 XenBlockDataPlane *xen_block_dataplane_create(XenDevice *xendev,
-                                              BlockConf *conf,
+                                              BlockBackend *blk,
+                                              unsigned int sector_size,
                                               IOThread *iothread)
 {
     XenBlockDataPlane *dataplane = g_new0(XenBlockDataPlane, 1);
 
     dataplane->xendev = xendev;
-    dataplane->blk = conf->blk;
+    dataplane->blk = blk;
+    dataplane->sector_size = sector_size;
 
     QLIST_INIT(&dataplane->inflight);
     QLIST_INIT(&dataplane->freelist);
@@ -803,7 +807,7 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
     }
 
     dataplane->event_channel =
-        xen_device_bind_event_channel(xendev, event_channel,
+        xen_device_bind_event_channel(xendev, dataplane->ctx, event_channel,
                                       xen_block_dataplane_event, dataplane,
                                       &local_err);
     if (local_err) {
diff --git a/hw/block/dataplane/xen-block.h b/hw/block/dataplane/xen-block.h
index d6fa6d2..76dcd51 100644
--- a/hw/block/dataplane/xen-block.h
+++ b/hw/block/dataplane/xen-block.h
@@ -15,7 +15,8 @@
 typedef struct XenBlockDataPlane XenBlockDataPlane;
 
 XenBlockDataPlane *xen_block_dataplane_create(XenDevice *xendev,
-                                              BlockConf *conf,
+                                              BlockBackend *blk,
+                                              unsigned int sector_size,
                                               IOThread *iothread);
 void xen_block_dataplane_destroy(XenBlockDataPlane *dataplane);
 void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index 4de537a..8f224ef 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -52,11 +52,25 @@ static void xen_block_connect(XenDevice *xendev, Error **errp)
     XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
     const char *type = object_get_typename(OBJECT(blockdev));
     XenBlockVdev *vdev = &blockdev->props.vdev;
+    BlockConf *conf = &blockdev->props.conf;
+    unsigned int feature_large_sector_size;
     unsigned int order, nr_ring_ref, *ring_ref, event_channel, protocol;
     char *str;
 
     trace_xen_block_connect(type, vdev->disk, vdev->partition);
 
+    if (xen_device_frontend_scanf(xendev, "feature-large-sector-size", "%u",
+                                  &feature_large_sector_size) != 1) {
+        feature_large_sector_size = 0;
+    }
+
+    if (feature_large_sector_size != 1 &&
+        conf->logical_block_size != XEN_BLKIF_SECTOR_SIZE) {
+        error_setg(errp, "logical_block_size != %u not supported by frontend",
+                   XEN_BLKIF_SECTOR_SIZE);
+        return;
+    }
+
     if (xen_device_frontend_scanf(xendev, "ring-page-order", "%u",
                                   &order) != 1) {
         nr_ring_ref = 1;
@@ -150,7 +164,7 @@ static void xen_block_set_size(XenBlockDevice *blockdev)
     const char *type = object_get_typename(OBJECT(blockdev));
     XenBlockVdev *vdev = &blockdev->props.vdev;
     BlockConf *conf = &blockdev->props.conf;
-    int64_t sectors = blk_getlength(conf->blk) / XEN_BLKIF_SECTOR_SIZE;
+    int64_t sectors = blk_getlength(conf->blk) / conf->logical_block_size;
     XenDevice *xendev = XEN_DEVICE(blockdev);
 
     trace_xen_block_size(type, vdev->disk, vdev->partition, sectors);
@@ -185,6 +199,7 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
     const char *type = object_get_typename(OBJECT(blockdev));
     XenBlockVdev *vdev = &blockdev->props.vdev;
     BlockConf *conf = &blockdev->props.conf;
+    BlockBackend *blk = conf->blk;
     Error *local_err = NULL;
 
     if (vdev->type == XEN_BLOCK_VDEV_TYPE_INVALID) {
@@ -206,8 +221,8 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
      * The blkif protocol does not deal with removable media, so it must
      * always be present, even for CDRom devices.
      */
-    assert(conf->blk);
-    if (!blk_is_inserted(conf->blk)) {
+    assert(blk);
+    if (!blk_is_inserted(blk)) {
         error_setg(errp, "device needs media, but drive is empty");
         return;
     }
@@ -224,26 +239,20 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
 
     blkconf_blocksizes(conf);
 
-    if (conf->logical_block_size != XEN_BLKIF_SECTOR_SIZE) {
-        error_setg(errp, "logical_block_size != %u not supported",
-                   XEN_BLKIF_SECTOR_SIZE);
-        return;
-    }
-
     if (conf->logical_block_size > conf->physical_block_size) {
         error_setg(
             errp, "logical_block_size > physical_block_size not supported");
         return;
     }
 
-    blk_set_dev_ops(conf->blk, &xen_block_dev_ops, blockdev);
-    blk_set_guest_block_size(conf->blk, conf->logical_block_size);
+    blk_set_dev_ops(blk, &xen_block_dev_ops, blockdev);
+    blk_set_guest_block_size(blk, conf->logical_block_size);
 
     if (conf->discard_granularity == -1) {
         conf->discard_granularity = conf->physical_block_size;
     }
 
-    if (blk_get_flags(conf->blk) & BDRV_O_UNMAP) {
+    if (blk_get_flags(blk) & BDRV_O_UNMAP) {
         xen_device_backend_printf(xendev, "feature-discard", "%u", 1);
         xen_device_backend_printf(xendev, "discard-granularity", "%u",
                                   conf->discard_granularity);
@@ -260,12 +269,13 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
                                blockdev->device_type);
 
     xen_device_backend_printf(xendev, "sector-size", "%u",
-                              XEN_BLKIF_SECTOR_SIZE);
+                              conf->logical_block_size);
 
     xen_block_set_size(blockdev);
 
     blockdev->dataplane =
-        xen_block_dataplane_create(xendev, conf, blockdev->props.iothread);
+        xen_block_dataplane_create(xendev, blk, conf->logical_block_size,
+                                   blockdev->props.iothread);
 }
 
 static void xen_block_frontend_changed(XenDevice *xendev,
diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
index a353693..9973352 100644
--- a/hw/block/xen_blkif.h
+++ b/hw/block/xen_blkif.h
@@ -1,9 +1,8 @@
 #ifndef XEN_BLKIF_H
 #define XEN_BLKIF_H
 
-#include "hw/xen/io/ring.h"
-#include <xen/io/blkif.h>
-#include <xen/io/protocols.h>
+#include "hw/xen/interface/io/blkif.h"
+#include "hw/xen/interface/io/protocols.h"
 
 /*
  * Not a real protocol.  Used to generate ring structs which contain