[Qemu-devel] [PATCH V6 02/15] xen: Support new libxc calls from xen unstable.

[anthony.perard@citrix.com]

From: Anthony PERARD <anthony.perard@citrix.com>

Update the libxenctrl calls in Qemu to use the new interface, otherwise
Qemu wouldn't be able to build against new versions of the library.

We also check libxenctrl version in configure, from Xen 3.3.0 to Xen
unstable.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 configure            |   67 ++++++++++++++++++++++++++++++++++++++++++++++++-
 hw/xen_backend.c     |   10 +++---
 hw/xen_backend.h     |    2 +-
 hw/xen_common.h      |   38 +++++++++++++++++-----------
 hw/xen_disk.c        |   12 ++++----
 hw/xen_domainbuild.c |    2 +-
 hw/xen_nic.c         |   16 ++++++------
 7 files changed, 109 insertions(+), 38 deletions(-)

diff --git a/configure b/configure
index 9ed05de..f6a7073 100755
--- a/configure
+++ b/configure
@@ -284,6 +284,7 @@ vnc_jpeg=""
 vnc_png=""
 vnc_thread="no"
 xen=""
+xen_ctrl_version=""
 linux_aio=""
 attr=""
 vhost_net=""
@@ -1135,20 +1136,81 @@ fi
 
 if test "$xen" != "no" ; then
   xen_libs="-lxenstore -lxenctrl -lxenguest"
+
+  # Xen unstable
   cat > $TMPC <<EOF
 #include <xenctrl.h>
 #include <xs.h>
-int main(void) { xs_daemon_open(); xc_interface_open(); return 0; }
+#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
+int main(void) {
+  xc_interface *xc;
+  xs_daemon_open();
+  xc_interface_open(0, 0, 0);
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  xc_gnttab_open(xc);
+  return 0;
+}
 EOF
   if compile_prog "" "$xen_libs" ; then
+    xen_ctrl_version=410
     xen=yes
-    libs_softmmu="$xen_libs $libs_softmmu"
+
+  # Xen 4.0.0
+  elif (
+      cat > $TMPC <<EOF
+#include <xenctrl.h>
+#include <xs.h>
+#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
+int main(void) {
+  xs_daemon_open();
+  xc_interface_open();
+  xc_gnttab_open();
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  return 0;
+}
+EOF
+      compile_prog "" "$xen_libs"
+    ) ; then
+    xen_ctrl_version=400
+    xen=yes
+
+  # Xen 3.3.0, 3.4.0
+  elif (
+      cat > $TMPC <<EOF
+#include <xenctrl.h>
+#include <xs.h>
+int main(void) {
+  xs_daemon_open();
+  xc_interface_open();
+  xc_gnttab_open();
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  return 0;
+}
+EOF
+      compile_prog "" "$xen_libs"
+    ) ; then
+    xen_ctrl_version=330
+    xen=yes
+
+  # Xen not found or unsupported
   else
     if test "$xen" = "yes" ; then
       feature_not_found "xen"
     fi
     xen=no
   fi
+
+  if test "$xen" = "yes"; then
+    libs_softmmu="$xen_libs $libs_softmmu"
+  fi
 fi
 
 ##########################################
@@ -2546,6 +2608,7 @@ if test "$bluez" = "yes" ; then
 fi
 if test "$xen" = "yes" ; then
   echo "CONFIG_XEN=y" >> $config_host_mak
+  echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
 fi
 if test "$io_thread" = "yes" ; then
   echo "CONFIG_IOTHREAD=y" >> $config_host_mak
diff --git a/hw/xen_backend.c b/hw/xen_backend.c
index 860b038..3e99751 100644
--- a/hw/xen_backend.c
+++ b/hw/xen_backend.c
@@ -43,7 +43,7 @@
 /* ------------------------------------------------------------- */
 
 /* public */
-int xen_xc;
+qemu_xc_interface xen_xc = XC_HANDLER_INITIAL_VALUE;
 struct xs_handle *xenstore = NULL;
 const char *xen_protocol;
 
@@ -216,7 +216,7 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
     fcntl(xc_evtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
 
     if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
-        xendev->gnttabdev = xc_gnttab_open();
+        xendev->gnttabdev = xc_gnttab_open(xen_xc);
         if (xendev->gnttabdev < 0) {
             xen_be_printf(NULL, 0, "can't open gnttab device\n");
             xc_evtchn_close(xendev->evtchndev);
@@ -269,7 +269,7 @@ static struct XenDevice *xen_be_del_xendev(int dom, int dev)
         if (xendev->evtchndev >= 0)
             xc_evtchn_close(xendev->evtchndev);
         if (xendev->gnttabdev >= 0)
-            xc_gnttab_close(xendev->gnttabdev);
+            xc_gnttab_close(xen_xc, xendev->gnttabdev);
 
         QTAILQ_REMOVE(&xendevs, xendev, next);
         qemu_free(xendev);
@@ -627,8 +627,8 @@ int xen_be_init(void)
     if (qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL) < 0)
         goto err;
 
-    xen_xc = xc_interface_open();
-    if (xen_xc == -1) {
+    xen_xc = xc_interface_open(NULL, NULL, 0);
+    if (xen_xc == XC_HANDLER_INITIAL_VALUE) {
         xen_be_printf(NULL, 0, "can't open xen interface\n");
         goto err;
     }
diff --git a/hw/xen_backend.h b/hw/xen_backend.h
index 1b428e3..7d84098 100644
--- a/hw/xen_backend.h
+++ b/hw/xen_backend.h
@@ -55,7 +55,7 @@ struct XenDevice {
 /* ------------------------------------------------------------- */
 
 /* variables */
-extern int xen_xc;
+extern qemu_xc_interface xen_xc;
 extern struct xs_handle *xenstore;
 extern const char *xen_protocol;
 
diff --git a/hw/xen_common.h b/hw/xen_common.h
index 8a55b44..9f75e52 100644
--- a/hw/xen_common.h
+++ b/hw/xen_common.h
@@ -1,6 +1,8 @@
 #ifndef QEMU_HW_XEN_COMMON_H
 #define QEMU_HW_XEN_COMMON_H 1
 
+#include "config-host.h"
+
 #include <stddef.h>
 #include <inttypes.h>
 
@@ -13,22 +15,28 @@
 #include "qemu-queue.h"
 
 /*
- * tweaks needed to build with different xen versions
- *  0x00030205 -> 3.1.0
- *  0x00030207 -> 3.2.0
- *  0x00030208 -> unstable
+ * We don't support Xen prior to 3.3.0.
  */
-#include <xen/xen-compat.h>
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030205
-# define evtchn_port_or_error_t int
-#endif
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030207
-# define xc_map_foreign_pages xc_map_foreign_batch
-#endif
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030208
-# define xen_mb()  mb()
-# define xen_rmb() rmb()
-# define xen_wmb() wmb()
+
+/* Xen unstable */
+#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 410
+typedef int qemu_xc_interface;
+#  define XC_HANDLER_INITIAL_VALUE               -1
+#  define xc_fd(xen_xc)                          xen_xc
+#  define xc_interface_open(l, dl, f)            xc_interface_open()
+#  define xc_gnttab_open(xc)                     xc_gnttab_open()
+#  define xc_gnttab_map_grant_ref(xc, gnt, domid, ref, flags) \
+    xc_gnttab_map_grant_ref(gnt, domid, ref, flags)
+#  define xc_gnttab_map_grant_refs(xc, gnt, count, domids, refs, flags) \
+    xc_gnttab_map_grant_refs(gnt, count, domids, refs, flags)
+#  define xc_gnttab_munmap(xc, gnt, pages, niov) xc_gnttab_munmap(gnt, pages, niov)
+#  define xc_gnttab_close(xc, dev)               xc_gnttab_close(dev)
+#else
+typedef xc_interface *qemu_xc_interface;
+#  define XC_HANDLER_INITIAL_VALUE NULL
+/* FIXME The fd of xen_xc is now xen_xc->fd */
+/* fd is the first field, so this works */
+#  define xc_fd(xen_xc)                          (*(int*)xen_xc)
 #endif
 
 #endif /* QEMU_HW_XEN_COMMON_H */
diff --git a/hw/xen_disk.c b/hw/xen_disk.c
index 47280ee..ec1365c 100644
--- a/hw/xen_disk.c
+++ b/hw/xen_disk.c
@@ -243,7 +243,7 @@ static void ioreq_unmap(struct ioreq *ioreq)
     if (batch_maps) {
         if (!ioreq->pages)
             return;
-        if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0)
+        if (xc_gnttab_munmap(xen_xc, gnt, ioreq->pages, ioreq->v.niov) != 0)
             xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
                           strerror(errno));
         ioreq->blkdev->cnt_map -= ioreq->v.niov;
@@ -252,7 +252,7 @@ static void ioreq_unmap(struct ioreq *ioreq)
         for (i = 0; i < ioreq->v.niov; i++) {
             if (!ioreq->page[i])
                 continue;
-            if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0)
+            if (xc_gnttab_munmap(xen_xc, gnt, ioreq->page[i], 1) != 0)
                 xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
                               strerror(errno));
             ioreq->blkdev->cnt_map--;
@@ -270,7 +270,7 @@ static int ioreq_map(struct ioreq *ioreq)
         return 0;
     if (batch_maps) {
         ioreq->pages = xc_gnttab_map_grant_refs
-            (gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
+            (xen_xc, gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
         if (ioreq->pages == NULL) {
             xen_be_printf(&ioreq->blkdev->xendev, 0,
                           "can't map %d grant refs (%s, %d maps)\n",
@@ -284,7 +284,7 @@ static int ioreq_map(struct ioreq *ioreq)
     } else  {
         for (i = 0; i < ioreq->v.niov; i++) {
             ioreq->page[i] = xc_gnttab_map_grant_ref
-                (gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
+                (xen_xc, gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
             if (ioreq->page[i] == NULL) {
                 xen_be_printf(&ioreq->blkdev->xendev, 0,
                               "can't map grant ref %d (%s, %d maps)\n",
@@ -684,7 +684,7 @@ static int blk_connect(struct XenDevice *xendev)
             blkdev->protocol = BLKIF_PROTOCOL_X86_64;
     }
 
-    blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
+    blkdev->sring = xc_gnttab_map_grant_ref(xen_xc, blkdev->xendev.gnttabdev,
                                             blkdev->xendev.dom,
                                             blkdev->ring_ref,
                                             PROT_READ | PROT_WRITE);
@@ -739,7 +739,7 @@ static void blk_disconnect(struct XenDevice *xendev)
     xen_be_unbind_evtchn(&blkdev->xendev);
 
     if (blkdev->sring) {
-        xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
+        xc_gnttab_munmap(xen_xc, blkdev->xendev.gnttabdev, blkdev->sring, 1);
         blkdev->cnt_map--;
         blkdev->sring = NULL;
     }
diff --git a/hw/xen_domainbuild.c b/hw/xen_domainbuild.c
index 7f1fd66..232a456 100644
--- a/hw/xen_domainbuild.c
+++ b/hw/xen_domainbuild.c
@@ -176,7 +176,7 @@ static int xen_domain_watcher(void)
     for (i = 3; i < n; i++) {
         if (i == fd[0])
             continue;
-        if (i == xen_xc)
+        if (i == xc_fd(xen_xc))
             continue;
         close(i);
     }
diff --git a/hw/xen_nic.c b/hw/xen_nic.c
index 8fcf856..2575541 100644
--- a/hw/xen_nic.c
+++ b/hw/xen_nic.c
@@ -166,7 +166,7 @@ static void net_tx_packets(struct XenNetDev *netdev)
                           (txreq.flags & NETTXF_more_data)      ? " more_data"      : "",
                           (txreq.flags & NETTXF_extra_info)     ? " extra_info"     : "");
 
-            page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+            page = xc_gnttab_map_grant_ref(xen_xc, netdev->xendev.gnttabdev,
                                            netdev->xendev.dom,
                                            txreq.gref, PROT_READ);
             if (page == NULL) {
@@ -185,7 +185,7 @@ static void net_tx_packets(struct XenNetDev *netdev)
             } else {
                 qemu_send_packet(&netdev->nic->nc, page + txreq.offset, txreq.size);
             }
-            xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
+            xc_gnttab_munmap(xen_xc, netdev->xendev.gnttabdev, page, 1);
             net_tx_response(netdev, &txreq, NETIF_RSP_OKAY);
         }
         if (!netdev->tx_work)
@@ -272,7 +272,7 @@ static ssize_t net_rx_packet(VLANClientState *nc, const uint8_t *buf, size_t siz
     memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq));
     netdev->rx_ring.req_cons = ++rc;
 
-    page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+    page = xc_gnttab_map_grant_ref(xen_xc, netdev->xendev.gnttabdev,
                                    netdev->xendev.dom,
                                    rxreq.gref, PROT_WRITE);
     if (page == NULL) {
@@ -282,7 +282,7 @@ static ssize_t net_rx_packet(VLANClientState *nc, const uint8_t *buf, size_t siz
         return -1;
     }
     memcpy(page + NET_IP_ALIGN, buf, size);
-    xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
+    xc_gnttab_munmap(xen_xc, netdev->xendev.gnttabdev, page, 1);
     net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0);
 
     return size;
@@ -350,11 +350,11 @@ static int net_connect(struct XenDevice *xendev)
         return -1;
     }
 
-    netdev->txs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+    netdev->txs = xc_gnttab_map_grant_ref(xen_xc, netdev->xendev.gnttabdev,
                                           netdev->xendev.dom,
                                           netdev->tx_ring_ref,
                                           PROT_READ | PROT_WRITE);
-    netdev->rxs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+    netdev->rxs = xc_gnttab_map_grant_ref(xen_xc, netdev->xendev.gnttabdev,
                                           netdev->xendev.dom,
                                           netdev->rx_ring_ref,
                                           PROT_READ | PROT_WRITE);
@@ -381,11 +381,11 @@ static void net_disconnect(struct XenDevice *xendev)
     xen_be_unbind_evtchn(&netdev->xendev);
 
     if (netdev->txs) {
-        xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
+        xc_gnttab_munmap(xen_xc, netdev->xendev.gnttabdev, netdev->txs, 1);
         netdev->txs = NULL;
     }
     if (netdev->rxs) {
-        xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
+        xc_gnttab_munmap(xen_xc, netdev->xendev.gnttabdev, netdev->rxs, 1);
         netdev->rxs = NULL;
     }
     if (netdev->nic) {
-- 
1.7.1