Make blktap support optional.

Enable it by default on Linux, disable it on non-Linux.

Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
committer: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

diff --git a/tools/Rules.mk b/tools/Rules.mk
index 95323b01bf2260b0e7acc39c32b5a3a0db7f4a3c..20126718e7d7981e352f25596dcdd969e00179b7 100644 (file)
--- a/tools/Rules.mk
+++ b/tools/Rules.mk
@@ -26,8 +26,19 @@ LDLIBS_libxenguest = -L$(XEN_LIBXC) -lxenguest
 CFLAGS_libxenstore = -I$(XEN_XENSTORE) $(CFLAGS_include)
 LDLIBS_libxenstore = -L$(XEN_XENSTORE) -lxenstore
 
+ifeq ($(CONFIG_Linux),y)
+LIBXL_BLKTAP = y
+else
+LIBXL_BLKTAP = n
+endif
+
+ifeq ($(LIBXL_BLKTAP),y)
 CFLAGS_libblktapctl = -I$(XEN_BLKTAP2)/control -I$(XEN_BLKTAP2)/include $(CFLAGS_include)
 LDLIBS_libblktapctl = -L$(XEN_BLKTAP2)/control -lblktapctl
+else
+CFLAGS_libblktapctl =
+LDLIBS_libblktapctl =
+endif
 
 X11_LDPATH = -L/usr/X11R6/$(LIBLEAFDIR)
 

diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile
index fbd3b5f966aa7deaf2065d381c1d830ba3175bad..fd5da4947e0fb35209e25f32a563e6b882d9a26d 100644 (file)
--- a/tools/libxl/Makefile
+++ b/tools/libxl/Makefile
@@ -18,6 +18,12 @@ CFLAGS += $(CFLAGS_libxenctrl) $(CFLAGS_libxenguest) $(CFLAGS_libxenstore) $(CFL
 LIBS = $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenstore) $(LDLIBS_libblktapctl) $(UTIL_LIBS)
 
 LIBXL_OBJS-y = osdeps.o libxl_paths.o libxl_bootloader.o
+ifeq ($(LIBXL_BLKTAP),y)
+LIBXL_OBJS-y += libxl_blktap2.o
+else
+LIBXL_OBJS-y += libxl_noblktap2.o
+endif
+
 LIBXL_OBJS = flexarray.o libxl.o libxl_pci.o libxl_dom.o libxl_exec.o libxl_xshelp.o libxl_device.o libxl_internal.o xenguest.o libxl_utils.o $(LIBXL_OBJS-y)
 
 AUTOINCS= libxlu_cfg_y.h libxlu_cfg_l.h

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 814fe04640fb7fbf508604629895aa20d3838373..e1ed0519bf2274d595e8a28ef94786a851da8cb2 100644 (file)
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -36,7 +36,6 @@
 #include "libxl_utils.h"
 #include "libxl_internal.h"
 #include "flexarray.h"
-#include "tap-ctl.h"
 
 #define PAGE_TO_MEMKB(pages) ((pages) * 4)
 
@@ -1715,27 +1714,6 @@ int libxl_confirm_device_model_startup(libxl_ctx *ctx,
 
 /******************************************************************************/
 
-static char *get_blktap2_device(libxl_gc *gc,
-                               const char *name, const char *type)
-{
-    int minor = tap_ctl_find_minor(type, name);
-    if (minor < 0)
-        return NULL;
-    return libxl_sprintf(gc, "/dev/xen/blktap-2/tapdev%d", minor);
-}
-
-static char *make_blktap2_device(libxl_gc *gc,
-                                const char *name, const char *type)
-{
-    char *params, *devname = NULL;
-    int err;
-    params = libxl_sprintf(gc, "%s:%s", type, name);
-    err = tap_ctl_create(params, &devname);
-    if (!err)
-        libxl_ptr_add(gc, devname);
-    return err ? NULL : devname;
-}
-
 int libxl_device_disk_add(libxl_ctx *ctx, uint32_t domid, libxl_device_disk *disk)
 {
     libxl_gc gc = LIBXL_INIT_GC(ctx);
@@ -1790,14 +1768,13 @@ int libxl_device_disk_add(libxl_ctx *ctx, uint32_t domid, libxl_device_disk *dis
         case PHYSTYPE_FILE:
             /* let's pretend is tap:aio for the moment */
             disk->phystype = PHYSTYPE_AIO;
-        case PHYSTYPE_AIO: case PHYSTYPE_QCOW: case PHYSTYPE_QCOW2: case PHYSTYPE_VHD: {
-            const char *msg;
-            if (!tap_ctl_check(&msg)) {
-                const char *type = device_disk_string_of_phystype(disk->phystype);
-                char *dev;
-                dev = get_blktap2_device(&gc, disk->physpath, type);
-                if (!dev)
-                    dev = make_blktap2_device(&gc, disk->physpath, type);
+        case PHYSTYPE_AIO:
+        case PHYSTYPE_QCOW:
+        case PHYSTYPE_QCOW2:
+        case PHYSTYPE_VHD:
+            if (libxl_blktap_enabled(&gc)) {
+                const char *dev = libxl_blktap_devpath(&gc,
+                                               disk->physpath, disk->phystype);
                 if (!dev) {
                     rc = ERROR_FAIL;
                     goto out_free;
@@ -1820,7 +1797,7 @@ int libxl_device_disk_add(libxl_ctx *ctx, uint32_t domid, libxl_device_disk *dis
 
             device.backend_kind = DEVICE_TAP;
             break;
-        }
+
         default:
             XL_LOG(ctx, XL_LOG_ERROR, "unrecognized disk physical type: %d\n", disk->phystype);
             rc = ERROR_INVAL;
@@ -1892,7 +1869,8 @@ int libxl_device_disk_del(libxl_ctx *ctx,
 char * libxl_device_disk_local_attach(libxl_ctx *ctx, libxl_device_disk *disk)
 {
     libxl_gc gc = LIBXL_INIT_GC(ctx);
-    char *dev = NULL, *ret;
+    const char *dev = NULL;
+    char *ret;
     int phystype = disk->phystype;
     switch (phystype) {
         case PHYSTYPE_PHY: {
@@ -1903,16 +1881,14 @@ char * libxl_device_disk_local_attach(libxl_ctx *ctx, libxl_device_disk *disk)
         case PHYSTYPE_FILE:
             /* let's pretend is tap:aio for the moment */
             phystype = PHYSTYPE_AIO;
-        case PHYSTYPE_AIO: case PHYSTYPE_QCOW: case PHYSTYPE_QCOW2: case PHYSTYPE_VHD: {
-            const char *msg;
-            if (!tap_ctl_check(&msg)) {
-                const char *type = device_disk_string_of_phystype(phystype);
-                dev = get_blktap2_device(&gc, disk->physpath, type);
-                if (!dev)
-                    dev = make_blktap2_device(&gc, disk->physpath, type);
-            }
+        case PHYSTYPE_AIO:
+        case PHYSTYPE_QCOW:
+        case PHYSTYPE_QCOW2:
+        case PHYSTYPE_VHD:
+            if (libxl_blktap_enabled(&gc))
+                dev = libxl_blktap_devpath(&gc, disk->physpath, phystype);
             break;
-        }
+
         default:
             XL_LOG(ctx, XL_LOG_ERROR, "unrecognized disk physical type: %d\n", phystype);
             break;

diff --git a/tools/libxl/libxl_blktap2.c b/tools/libxl/libxl_blktap2.c
new file mode 100644 (file)
index 0000000..17c18fb
--- /dev/null
+++ b/tools/libxl/libxl_blktap2.c
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2010      Advanced Micro Devices
+ * Author Christoph Egger <Christoph.Egger@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; version 2.1 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ */
+
+#include "libxl.h"
+#include "libxl_osdeps.h"
+#include "libxl_internal.h"
+
+#include "tap-ctl.h"
+
+int libxl_blktap_enabled(libxl_gc *gc)
+{
+    const char *msg;
+    return !tap_ctl_check(&msg);
+}
+
+const char *libxl_blktap_devpath(libxl_gc *gc,
+                                 const char *disk,
+                                 libxl_disk_phystype phystype)
+{
+    const char *type;
+    char *params, *devname;
+    int minor, err;
+
+    type = device_disk_string_of_phystype(phystype);
+    minor = tap_ctl_find_minor(type, disk);
+    if (minor >= 0) {
+        devname = libxl_sprintf(gc, "/dev/xen/blktap-2/tapdev%d", minor);
+        if (devname)
+            return devname;
+    }
+
+    params = libxl_sprintf(gc, "%s:%s", type, disk);
+    err = tap_ctl_create(params, &devname);
+    if (!err) {
+        libxl_ptr_add(gc, devname);
+        return devname;
+    }
+
+    return NULL;
+}

diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index dc6e1c8e8fcbda248dfec7c77539be3c88eb78e5..ec75dbbdb0e48037d8a3476806eb69a95e1bcb8b 100644 (file)
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -248,4 +248,23 @@ _hidden char *libxl_abs_path(libxl_gc *gc, char *s, const char *path);
 _hidden char *_libxl_domid_to_name(libxl_gc *gc, uint32_t domid);
 _hidden char *_libxl_poolid_to_name(libxl_gc *gc, uint32_t poolid);
 
+/*
+ * blktap2 support
+ */
+
+/* libxl_blktap_enabled:
+ *    return true if blktap/blktap2 support is available.
+ */
+int libxl_blktap_enabled(libxl_gc *gc);
+
+/* libxl_blktap_devpath:
+ *    Argument: path and disk image as specified in config file.
+ *      The type specifies whether this is aio, qcow, qcow2, etc.
+ *    returns device path xenstore wants to have. returns NULL
+ *      if no device corresponds to the disk.
+ */
+const char *libxl_blktap_devpath(libxl_gc *gc,
+                                 const char *disk,
+                                 libxl_disk_phystype phystype);
+
 #endif

diff --git a/tools/libxl/libxl_noblktap2.c b/tools/libxl/libxl_noblktap2.c
new file mode 100644 (file)
index 0000000..afefd4a
--- /dev/null
+++ b/tools/libxl/libxl_noblktap2.c
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2010      Advanced Micro Devices
+ * Author Christoph Egger <Christoph.Egger@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; version 2.1 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ */
+
+#include "libxl.h"
+#include "libxl_osdeps.h"
+#include "libxl_internal.h"
+
+int libxl_blktap_enabled(libxl_gc *gc)
+{
+    return 0;
+}
+
+const char *libxl_blktap_devpath(libxl_gc *gc,
+                                 const char *disk,
+                                 libxl_disk_phystype phystype)
+{
+    return NULL;
+}