Merge tag 'xenfv-2' of git://git.infradead.org/users/dwmw2/qemu into staging

Enable PV backends with Xen/KVM emulation

This is phase 2, following on from the basic platform support which was
already merged.

 • Add a simple single-tenant internal XenStore implementation
 • Indirect Xen gnttab/evtchn/foreignmem/xenstore through operations table
 • Provide emulated back ends for Xen operations
 • Header cleanups to allow PV back ends to build without Xen itself
 • Enable PV back ends in emulated mode
 • Documentation update

Tested-by: Paul Durrant <paul@xen.org>
... on real Xen (master branch, 4.18) with a Debian guest.

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# gpg:                 aka "David Woodhouse <dwmw@amazon.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 314B 08AC D0DE 4811 33A5  F286 9BE9 80FD 0AC0 1544

* tag 'xenfv-2' of git://git.infradead.org/users/dwmw2/qemu: (27 commits)
  docs: Update Xen-on-KVM documentation for PV disk support
  MAINTAINERS: Add entry for Xen on KVM emulation
  i386/xen: Initialize Xen backends from pc_basic_device_init() for emulation
  hw/xen: Implement soft reset for emulated gnttab
  hw/xen: Map guest XENSTORE_PFN grant in emulated Xenstore
  hw/xen: Add emulated implementation of XenStore operations
  hw/xen: Add emulated implementation of grant table operations
  hw/xen: Hook up emulated implementation for event channel operations
  hw/xen: Only advertise ring-page-order for xen-block if gnttab supports it
  hw/xen: Avoid crash when backend watch fires too early
  hw/xen: Build PV backend drivers for CONFIG_XEN_BUS
  hw/xen: Rename xen_common.h to xen_native.h
  hw/xen: Use XEN_PAGE_SIZE in PV backend drivers
  hw/xen: Move xenstore_store_pv_console_info to xen_console.c
  hw/xen: Add xenstore operations to allow redirection to internal emulation
  hw/xen: Add foreignmem operations to allow redirection to internal emulation
  hw/xen: Pass grant ref to gnttab unmap operation
  hw/xen: Add gnttab operations to allow redirection to internal emulation
  hw/xen: Add evtchn operations to allow redirection to internal emulation
  hw/xen: Create initial XenStore nodes
  ...

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

2 files changed, 21 insertions, 10 deletions

diff --git a/hw/usb/meson.build b/hw/usb/meson.build
index bdf34cb..599dc24 100644
--- a/hw/usb/meson.build
+++ b/hw/usb/meson.build
@@ -84,6 +84,6 @@ if libusb.found()
   hw_usb_modules += {'host': usbhost_ss}
 endif
 
-softmmu_ss.add(when: ['CONFIG_USB', 'CONFIG_XEN', libusb], if_true: files('xen-usb.c'))
+softmmu_ss.add(when: ['CONFIG_USB', 'CONFIG_XEN_BUS', libusb], if_true: files('xen-usb.c'))
 
 modules += { 'hw-usb': hw_usb_modules }
diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
index 0f7369e..66cb3f7 100644
--- a/hw/usb/xen-usb.c
+++ b/hw/usb/xen-usb.c
@@ -101,6 +101,8 @@ struct usbback_hotplug {
 struct usbback_info {
     struct XenLegacyDevice         xendev;  /* must be first */
     USBBus                   bus;
+    uint32_t                 urb_ring_ref;
+    uint32_t                 conn_ring_ref;
     void                     *urb_sring;
     void                     *conn_sring;
     struct usbif_urb_back_ring urb_ring;
@@ -159,7 +161,7 @@ static int usbback_gnttab_map(struct usbback_req *usbback_req)
 
     for (i = 0; i < nr_segs; i++) {
         if ((unsigned)usbback_req->req.seg[i].offset +
-            (unsigned)usbback_req->req.seg[i].length > XC_PAGE_SIZE) {
+            (unsigned)usbback_req->req.seg[i].length > XEN_PAGE_SIZE) {
             xen_pv_printf(xendev, 0, "segment crosses page boundary\n");
             return -EINVAL;
         }
@@ -183,7 +185,7 @@ static int usbback_gnttab_map(struct usbback_req *usbback_req)
 
         for (i = 0; i < usbback_req->nr_buffer_segs; i++) {
             seg = usbback_req->req.seg + i;
-            addr = usbback_req->buffer + i * XC_PAGE_SIZE + seg->offset;
+            addr = usbback_req->buffer + i * XEN_PAGE_SIZE + seg->offset;
             qemu_iovec_add(&usbback_req->packet.iov, addr, seg->length);
         }
     }
@@ -277,10 +279,11 @@ static int usbback_init_packet(struct usbback_req *usbback_req)
 static void usbback_do_response(struct usbback_req *usbback_req, int32_t status,
                                 int32_t actual_length, int32_t error_count)
 {
+    uint32_t ref[USBIF_MAX_SEGMENTS_PER_REQUEST];
     struct usbback_info *usbif;
     struct usbif_urb_response *res;
     struct XenLegacyDevice *xendev;
-    unsigned int notify;
+    unsigned int notify, i;
 
     usbif = usbback_req->usbif;
     xendev = &usbif->xendev;
@@ -293,13 +296,19 @@ static void usbback_do_response(struct usbback_req *usbback_req, int32_t status,
     }
 
     if (usbback_req->buffer) {
-        xen_be_unmap_grant_refs(xendev, usbback_req->buffer,
+        for (i = 0; i < usbback_req->nr_buffer_segs; i++) {
+            ref[i] = usbback_req->req.seg[i].gref;
+        }
+        xen_be_unmap_grant_refs(xendev, usbback_req->buffer, ref,
                                 usbback_req->nr_buffer_segs);
         usbback_req->buffer = NULL;
     }
 
     if (usbback_req->isoc_buffer) {
-        xen_be_unmap_grant_refs(xendev, usbback_req->isoc_buffer,
+        for (i = 0; i < usbback_req->nr_extra_segs; i++) {
+            ref[i] = usbback_req->req.seg[i + usbback_req->req.nr_buffer_segs].gref;
+        }
+        xen_be_unmap_grant_refs(xendev, usbback_req->isoc_buffer, ref,
                                 usbback_req->nr_extra_segs);
         usbback_req->isoc_buffer = NULL;
     }
@@ -832,11 +841,11 @@ static void usbback_disconnect(struct XenLegacyDevice *xendev)
     xen_pv_unbind_evtchn(xendev);
 
     if (usbif->urb_sring) {
-        xen_be_unmap_grant_ref(xendev, usbif->urb_sring);
+        xen_be_unmap_grant_ref(xendev, usbif->urb_sring, usbif->urb_ring_ref);
         usbif->urb_sring = NULL;
     }
     if (usbif->conn_sring) {
-        xen_be_unmap_grant_ref(xendev, usbif->conn_sring);
+        xen_be_unmap_grant_ref(xendev, usbif->conn_sring, usbif->conn_ring_ref);
         usbif->conn_sring = NULL;
     }
 
@@ -889,10 +898,12 @@ static int usbback_connect(struct XenLegacyDevice *xendev)
         return -1;
     }
 
+    usbif->urb_ring_ref = urb_ring_ref;
+    usbif->conn_ring_ref = conn_ring_ref;
     urb_sring = usbif->urb_sring;
     conn_sring = usbif->conn_sring;
-    BACK_RING_INIT(&usbif->urb_ring, urb_sring, XC_PAGE_SIZE);
-    BACK_RING_INIT(&usbif->conn_ring, conn_sring, XC_PAGE_SIZE);
+    BACK_RING_INIT(&usbif->urb_ring, urb_sring, XEN_PAGE_SIZE);
+    BACK_RING_INIT(&usbif->conn_ring, conn_sring, XEN_PAGE_SIZE);
 
     xen_be_bind_evtchn(xendev);