Xen queue

* xen-block, the Xen PV backend, now handles resize.
 * configure cleanup.
 * xen-bus fix.
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Merge remote-tracking branch 'remotes/aperard/tags/pull-xen-20190204' into staging

Xen queue

* xen-block, the Xen PV backend, now handles resize.
* configure cleanup.
* xen-bus fix.

# gpg: Signature made Mon 04 Feb 2019 11:16:13 GMT
# gpg:                using RSA key F80C006308E22CFD8A92E7980CF5572FD7FB55AF
# gpg:                issuer "anthony.perard@citrix.com"
# gpg: Good signature from "Anthony PERARD <anthony.perard@gmail.com>" [marginal]
# gpg:                 aka "Anthony PERARD <anthony.perard@citrix.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 5379 2F71 024C 600F 778A  7161 D8D5 7199 DF83 42C8
#      Subkey fingerprint: F80C 0063 08E2 2CFD 8A92  E798 0CF5 572F D7FB 55AF

* remotes/aperard/tags/pull-xen-20190204:
  xen-block: handle resize callback
  xen: fix xen-bus state model to allow frontend re-connection
  configure: Don't add Xen's libs to LDFLAGS
  configure: xen: Stop build-testing for xc_domain_create

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

configure

@@ -2359,7 +2359,6 @@ if test "$xen" != "no" ; then
     fi
     QEMU_CFLAGS="$QEMU_CFLAGS $($pkg_config --cflags $xen_pc)"
     libs_softmmu="$($pkg_config --libs $xen_pc) $libs_softmmu"
-    LDFLAGS="$($pkg_config --libs $xen_pc) $LDFLAGS"
   else
 
     xen_libs="-lxenstore -lxenctrl -lxenguest"
@@ -2474,7 +2473,6 @@ int main(void) {
   xenforeignmemory_handle *xfmem;
   xenevtchn_handle *xe;
   xengnttab_handle *xg;
-  xen_domain_handle_t handle;
   xengnttab_grant_copy_segment_t* seg = NULL;
 
   xs_daemon_open();
@@ -2484,7 +2482,6 @@ int main(void) {
   xc_domain_add_to_physmap(0, 0, XENMAPSPACE_gmfn, 0, 0);
   xc_hvm_inject_msi(xc, 0, 0xf0000000, 0x00000000);
   xc_hvm_create_ioreq_server(xc, 0, HVM_IOREQSRV_BUFIOREQ_ATOMIC, NULL);
-  xc_domain_create(xc, 0, handle, 0, NULL, NULL);
 
   xfmem = xenforeignmemory_open(0, 0);
   xenforeignmemory_map(xfmem, 0, 0, 0, 0, 0);
@@ -2526,7 +2523,6 @@ int main(void) {
   xenforeignmemory_handle *xfmem;
   xenevtchn_handle *xe;
   xengnttab_handle *xg;
-  xen_domain_handle_t handle;
 
   xs_daemon_open();
 
@@ -2535,7 +2531,6 @@ int main(void) {
   xc_domain_add_to_physmap(0, 0, XENMAPSPACE_gmfn, 0, 0);
   xc_hvm_inject_msi(xc, 0, 0xf0000000, 0x00000000);
   xc_hvm_create_ioreq_server(xc, 0, HVM_IOREQSRV_BUFIOREQ_ATOMIC, NULL);
-  xc_domain_create(xc, 0, handle, 0, NULL, NULL);
 
   xfmem = xenforeignmemory_open(0, 0);
   xenforeignmemory_map(xfmem, 0, 0, 0, 0, 0);
@@ -2553,21 +2548,6 @@ EOF
       then
       xen_ctrl_version=40701
       xen=yes
-    elif
-        cat > $TMPC <<EOF &&
-#include <xenctrl.h>
-#include <stdint.h>
-int main(void) {
-  xc_interface *xc = NULL;
-  xen_domain_handle_t handle;
-  xc_domain_create(xc, 0, handle, 0, NULL, NULL);
-  return 0;
-}
-EOF
-        compile_prog "" "$xen_libs"
-      then
-      xen_ctrl_version=40700
-      xen=yes
 
     # Xen 4.6
     elif

hw/block/dataplane/xen-block.c

@@ -50,7 +50,6 @@ struct XenBlockDataPlane {
     unsigned int nr_ring_ref;
     void *sring;
     int64_t file_blk;
-    int64_t file_size;
     int protocol;
     blkif_back_rings_t rings;
     int more_work;
@@ -189,7 +188,7 @@ static int xen_block_parse_request(XenBlockRequest *request)
                request->req.seg[i].first_sect + 1) * dataplane->file_blk;
         request->size += len;
     }
-    if (request->start + request->size > dataplane->file_size) {
+    if (request->start + request->size > blk_getlength(dataplane->blk)) {
         error_report("error: access beyond end of file");
         goto err;
     }
@@ -638,7 +637,6 @@ XenBlockDataPlane *xen_block_dataplane_create(XenDevice *xendev,
     dataplane->xendev = xendev;
     dataplane->file_blk = conf->logical_block_size;
     dataplane->blk = conf->blk;
-    dataplane->file_size = blk_getlength(dataplane->blk);
 
     QLIST_INIT(&dataplane->inflight);
     QLIST_INIT(&dataplane->freelist);

hw/block/trace-events

@@ -126,6 +126,7 @@ xen_block_realize(const char *type, uint32_t disk, uint32_t partition) "%s d%up%
 xen_block_connect(const char *type, uint32_t disk, uint32_t partition) "%s d%up%u"
 xen_block_disconnect(const char *type, uint32_t disk, uint32_t partition) "%s d%up%u"
 xen_block_unrealize(const char *type, uint32_t disk, uint32_t partition) "%s d%up%u"
+xen_block_size(const char *type, uint32_t disk, uint32_t partition, int64_t sectors) "%s d%up%u %"PRIi64
 xen_disk_realize(void) ""
 xen_disk_unrealize(void) ""
 xen_cdrom_realize(void) ""

hw/block/xen-block.c

@@ -144,6 +144,38 @@ static void xen_block_unrealize(XenDevice *xendev, Error **errp)
     }
 }
 
+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) / conf->logical_block_size;
+    XenDevice *xendev = XEN_DEVICE(blockdev);
+
+    trace_xen_block_size(type, vdev->disk, vdev->partition, sectors);
+
+    xen_device_backend_printf(xendev, "sectors", "%"PRIi64, sectors);
+}
+
+static void xen_block_resize_cb(void *opaque)
+{
+    XenBlockDevice *blockdev = opaque;
+    XenDevice *xendev = XEN_DEVICE(blockdev);
+    enum xenbus_state state = xen_device_backend_get_state(xendev);
+
+    xen_block_set_size(blockdev);
+
+    /*
+     * Mimic the behaviour of Linux xen-blkback and re-write the state
+     * to trigger the frontend watch.
+     */
+    xen_device_backend_printf(xendev, "state", "%u", state);
+}
+
+static const BlockDevOps xen_block_dev_ops = {
+    .resize_cb = xen_block_resize_cb,
+};
+
 static void xen_block_realize(XenDevice *xendev, Error **errp)
 {
     XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
@@ -180,7 +212,7 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
     }
 
     if (!blkconf_apply_backend_options(conf, blockdev->info & VDISK_READONLY,
-                                       false, errp)) {
+                                       true, errp)) {
         return;
     }
 
@@ -197,6 +229,7 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
         return;
     }
 
+    blk_set_dev_ops(conf->blk, &xen_block_dev_ops, blockdev);
     blk_set_guest_block_size(conf->blk, conf->logical_block_size);
 
     if (conf->discard_granularity > 0) {
@@ -215,9 +248,8 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
 
     xen_device_backend_printf(xendev, "sector-size", "%u",
                               conf->logical_block_size);
-    xen_device_backend_printf(xendev, "sectors", "%"PRIi64,
+
-                              blk_getlength(conf->blk) /
+    xen_block_set_size(blockdev);
-                              conf->logical_block_size);
 
     blockdev->dataplane =
         xen_block_dataplane_create(xendev, conf, blockdev->props.iothread);

hw/xen/xen-bus.c

@@ -547,16 +547,11 @@ static void xen_device_backend_changed(void *opaque)
     }
 
     /*
-     * If a backend is still 'online' then its state should be cycled
+     * If a backend is still 'online' then we should leave it alone but,
-     * back round to InitWait in order for a new frontend instance to
+     * if a backend is not 'online', then the device should be destroyed
-     * connect. This may happen when, for example, a frontend driver is
+     * once the state is Closed.
-     * re-installed or updated.
-     * If a backend is not 'online' then the device should be destroyed.
      */
-    if (xendev->backend_online &&
+    if (!xendev->backend_online &&
-        xendev->backend_state == XenbusStateClosed) {
-        xen_device_backend_set_state(xendev, XenbusStateInitWait);
-    } else if (!xendev->backend_online &&
         (xendev->backend_state == XenbusStateClosed ||
          xendev->backend_state == XenbusStateInitialising ||
          xendev->backend_state == XenbusStateInitWait ||
@@ -715,6 +710,17 @@ static void xen_device_frontend_changed(void *opaque)
 
     xen_device_frontend_set_state(xendev, state);
 
+    if (state == XenbusStateInitialising &&
+        xendev->backend_state == XenbusStateClosed &&
+        xendev->backend_online) {
+        /*
+         * The frontend is re-initializing so switch back to
+         * InitWait.
+         */
+        xen_device_backend_set_state(xendev, XenbusStateInitWait);
+        return;
+    }
+
     if (xendev_class->frontend_changed) {
         Error *local_err = NULL;