xen/551ac326-xentop-add-support-for-qdisk.patch

Index: xen-4.5.1-testing/tools/libxl/libxl_dm.c
===================================================================
--- xen-4.5.1-testing.orig/tools/libxl/libxl_dm.c
+++ xen-4.5.1-testing/tools/libxl/libxl_dm.c
@@ -445,6 +445,15 @@ static char ** libxl__build_device_model
     flexarray_append(dm_args, "-mon");
     flexarray_append(dm_args, "chardev=libxl-cmd,mode=control");
 
+    flexarray_append(dm_args, "-chardev");
+    flexarray_append(dm_args,
+                     libxl__sprintf(gc, "socket,id=libxenstat-cmd,"
+                                    "path=%s/qmp-libxenstat-%d,server,nowait",
+                                    libxl__run_dir_path(), guest_domid));
+
+    flexarray_append(dm_args, "-mon");
+    flexarray_append(dm_args, "chardev=libxenstat-cmd,mode=control");
+
     for (i = 0; i < guest_config->num_channels; i++) {
         connection = guest_config->channels[i].connection;
         devid = guest_config->channels[i].devid;
Index: xen-4.5.1-testing/tools/libxl/libxl_qmp.c
===================================================================
--- xen-4.5.1-testing.orig/tools/libxl/libxl_qmp.c
+++ xen-4.5.1-testing/tools/libxl/libxl_qmp.c
@@ -723,6 +723,13 @@ void libxl__qmp_cleanup(libxl__gc *gc, u
             LOGE(ERROR, "Failed to remove QMP socket file %s", qmp_socket);
         }
     }
+
+    qmp_socket = GCSPRINTF("%s/qmp-libxenstat-%d", libxl__run_dir_path(), domid);
+    if (unlink(qmp_socket) == -1) {
+        if (errno != ENOENT) {
+            LOGE(ERROR, "Failed to remove QMP socket file %s", qmp_socket);
+        }
+    }
 }
 
 int libxl__qmp_query_serial(libxl__qmp_handler *qmp)
Index: xen-4.5.1-testing/tools/xenstat/libxenstat/Makefile
===================================================================
--- xen-4.5.1-testing.orig/tools/xenstat/libxenstat/Makefile
+++ xen-4.5.1-testing/tools/xenstat/libxenstat/Makefile
@@ -24,7 +24,7 @@ MINOR=0
 LIB=src/libxenstat.a
 SHLIB=src/libxenstat.so.$(MAJOR).$(MINOR)
 SHLIB_LINKS=src/libxenstat.so.$(MAJOR) src/libxenstat.so
-OBJECTS-y=src/xenstat.o
+OBJECTS-y=src/xenstat.o src/xenstat_qmp.o
 OBJECTS-$(CONFIG_Linux) += src/xenstat_linux.o
 OBJECTS-$(CONFIG_SunOS) += src/xenstat_solaris.o
 OBJECTS-$(CONFIG_NetBSD) += src/xenstat_netbsd.o
@@ -32,7 +32,7 @@ OBJECTS-$(CONFIG_FreeBSD) += src/xenstat
 SONAME_FLAGS=-Wl,$(SONAME_LDFLAG) -Wl,libxenstat.so.$(MAJOR)
 
 CFLAGS+=-fPIC
-CFLAGS+=-Isrc $(CFLAGS_libxenctrl) $(CFLAGS_libxenstore) $(CFLAGS_xeninclude)
+CFLAGS+=-Isrc $(CFLAGS_libxenctrl) $(CFLAGS_libxenstore) $(CFLAGS_xeninclude) -include $(XEN_ROOT)/tools/config.h
 
 LDLIBS-y = $(LDLIBS_libxenstore) $(LDLIBS_libxenctrl)
 LDLIBS-$(CONFIG_SunOS) += -lkstat
Index: xen-4.5.1-testing/tools/xenstat/xentop/Makefile
===================================================================
--- xen-4.5.1-testing.orig/tools/xenstat/xentop/Makefile
+++ xen-4.5.1-testing/tools/xenstat/xentop/Makefile
@@ -19,7 +19,7 @@ all install xentop:
 else
 
 CFLAGS += -DGCC_PRINTF -Werror $(CFLAGS_libxenstat)
-LDLIBS += $(LDLIBS_libxenstat) $(CURSES_LIBS) $(SOCKET_LIBS) -lm
+LDLIBS += $(LDLIBS_libxenstat) $(CURSES_LIBS) $(SOCKET_LIBS) -lm -lyajl
 CFLAGS += -DHOST_$(XEN_OS)
 
 # Include configure output (config.h) to headers search path
Index: xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat_priv.h
===================================================================
--- xen-4.5.1-testing.orig/tools/xenstat/libxenstat/src/xenstat_priv.h
+++ xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat_priv.h
@@ -109,5 +109,7 @@ extern int xenstat_collect_networks(xens
 extern void xenstat_uninit_networks(xenstat_handle * handle);
 extern int xenstat_collect_vbds(xenstat_node * node);
 extern void xenstat_uninit_vbds(xenstat_handle * handle);
+extern void read_attributes_qdisk(xenstat_node * node);
+extern xenstat_vbd *xenstat_save_vbd(xenstat_domain * domain, xenstat_vbd * vbd);
 
 #endif /* XENSTAT_PRIV_H */
Index: xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat.c
===================================================================
--- xen-4.5.1-testing.orig/tools/xenstat/libxenstat/src/xenstat.c
+++ xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat.c
@@ -657,6 +657,27 @@ static void xenstat_uninit_xen_version(x
  * VBD functions
  */
 
+/* Save VBD information */
+xenstat_vbd *xenstat_save_vbd(xenstat_domain *domain, xenstat_vbd *vbd)
+{
+        xenstat_vbd *vbds = domain->vbds;
+
+        domain->num_vbds++;
+        domain->vbds = realloc(domain->vbds,
+                               domain->num_vbds *
+                               sizeof(xenstat_vbd));
+
+        if (domain->vbds == NULL) {
+                domain->num_vbds = 0;
+                free(vbds);
+        }
+        else {
+                domain->vbds[domain->num_vbds - 1] = *vbd;
+        }
+
+        return domain->vbds;
+}
+
 /* Free VBD information */
 static void xenstat_free_vbds(xenstat_node * node)
 {
Index: xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat_linux.c
===================================================================
--- xen-4.5.1-testing.orig/tools/xenstat/libxenstat/src/xenstat_linux.c
+++ xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat_linux.c
@@ -417,6 +417,9 @@ int xenstat_collect_vbds(xenstat_node *
 		}
 	}
 
+	/* Get qdisk statistics */
+	read_attributes_qdisk(node);
+
 	rewinddir(priv->sysfsvbd);
 
 	for(dp = readdir(priv->sysfsvbd); dp != NULL ;
@@ -477,18 +480,10 @@ int xenstat_collect_vbds(xenstat_node *
 			continue;
 		}
 
-		if (domain->vbds == NULL) {
-			domain->num_vbds = 1;
-			domain->vbds = malloc(sizeof(xenstat_vbd));
-		} else {
-			domain->num_vbds++;
-			domain->vbds = realloc(domain->vbds,
-					       domain->num_vbds *
-					       sizeof(xenstat_vbd));
-		}
-		if (domain->vbds == NULL)
+		if ((xenstat_save_vbd(domain, &vbd)) == NULL) {
+			perror("Allocation error");
 			return 0;
-		domain->vbds[domain->num_vbds - 1] = vbd;
+		}
 	}
 
 	return 1;	
Index: xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat_qmp.c
===================================================================
--- /dev/null
+++ xen-4.5.1-testing/tools/xenstat/libxenstat/src/xenstat_qmp.c
@@ -0,0 +1,451 @@
+/* libxenstat: statistics-collection library for Xen
+ *
+ * This library 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; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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 <fcntl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/poll.h>
+#include <sys/un.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <xenctrl.h>
+
+#include "xenstat_priv.h"
+
+#ifdef HAVE_YAJL_YAJL_VERSION_H
+#  include <yajl/yajl_version.h>
+#endif
+
+/* YAJL version check */
+#if defined(YAJL_MAJOR) && (YAJL_MAJOR > 1)
+#  define HAVE_YAJL_V2 1
+#endif
+
+#ifdef HAVE_YAJL_V2
+
+#include <yajl/yajl_tree.h>
+
+static unsigned char *qmp_query(int, char *);
+
+enum query_blockstats {
+    QMP_STATS_RETURN  = 0,
+    QMP_STATS_DEVICE  = 1,
+    QMP_STATS         = 2,
+    QMP_RD_BYTES      = 3,
+    QMP_WR_BYTES      = 4,
+    QMP_RD_OPERATIONS = 5,
+    QMP_WR_OPERATIONS = 6,
+};
+
+enum query_block {
+    QMP_BLOCK_RETURN  = 0,
+    QMP_BLOCK_DEVICE  = 1,
+    QMP_INSERTED      = 2,
+    QMP_FILE          = 3,
+};
+
+
+/* Given the qmp device name, get the image filename associated with it
+   QMP Syntax for querying block infomation:
+     In: { "execute": "query-block" }
+     Out: {"return": [{
+            "device": 'str, "locked": 'bool', "removable": bool,
+            "inserted": {
+              "iops_rd": 'int',
+              "image": {
+                "virtual-size": 'int', "filename": 'str', "cluster-size": 'int',
+                "format": 'str', "actual-size": 'int', "dirty-flag": 'bool'
+              },
+              "iops_wr": 'int', "ro": 'bool', "backing_file_depth": 'int',
+              "drv": 'str', "iops": 'int', "bps_wr": 'int', "encrypted": 'bool',
+              "bps": 'int', "bps_rd": 'int',
+              "file": 'str', "encryption_key_missing": 'bool'
+            },
+            "type": 'str'
+          }]}
+*/
+static char *qmp_get_block_image(xenstat_node *node, char *qmp_devname, int qfd)
+{
+	char *tmp, *file = NULL;
+	char *query_block_cmd = "{ \"execute\": \"query-block\" }";
+	static const char *const qblock[] = {
+		[ QMP_BLOCK_RETURN  ] = "return",
+		[ QMP_BLOCK_DEVICE  ] = "device",
+		[ QMP_INSERTED      ] = "inserted",
+		[ QMP_FILE          ] = "file",
+	};
+	const char *ptr[] = {0, 0};
+	unsigned char *qmp_stats;
+	yajl_val info, ret_obj, dev_obj, n;
+	int i;
+
+	if ((qmp_stats = qmp_query(qfd, query_block_cmd)) == NULL)
+		return NULL;
+
+	/* Use libyajl version 2.0.3 or newer for the tree parser feature with bug fixes */
+	if ((info = yajl_tree_parse((char *)qmp_stats, NULL, 0)) == NULL) {
+		free(qmp_stats);
+		return NULL;
+	}
+
+	ptr[0] = qblock[QMP_BLOCK_RETURN]; /* "return" */
+	if ((ret_obj = yajl_tree_get(info, ptr, yajl_t_array)) == NULL)
+		goto done;
+
+	for (i=0; i<YAJL_GET_ARRAY(ret_obj)->len; i++) {
+		n = YAJL_GET_ARRAY(ret_obj)->values[i];
+
+		ptr[0] = qblock[QMP_BLOCK_DEVICE]; /* "device" */
+		if ((dev_obj = yajl_tree_get(n, ptr, yajl_t_any)) != NULL) {
+			tmp = YAJL_GET_STRING(dev_obj);
+			if (strcmp(qmp_devname, tmp))
+				continue;
+		}
+		else
+			continue;
+
+		ptr[0] = qblock[QMP_INSERTED]; /* "inserted" */
+		n = yajl_tree_get(n, ptr, yajl_t_any);
+		if (n) {
+			ptr[0] = qblock[QMP_FILE]; /* "file" */
+			n = yajl_tree_get(n, ptr, yajl_t_any);
+			if (n && YAJL_IS_STRING(n)) {
+				tmp = YAJL_GET_STRING(n);
+				file = malloc(strlen(tmp)+1);
+				if (file != NULL)
+					strcpy(file, tmp);
+				goto done;
+			}
+		}
+	}
+done:
+	yajl_tree_free(info);
+	return file;
+}
+
+
+/* Given a QMP device name, lookup the associated xenstore qdisk device id */
+static void lookup_xenstore_devid(xenstat_node * node, unsigned int domid, char *qmp_devname,
+	int qfd, unsigned int *dev, unsigned int *sector_size)
+{
+	char **dev_ids, *tmp, *ptr, *image, path[80];
+	unsigned int num_dev_ids;
+	int i, devid;
+
+	/* Get all the qdisk dev IDs associated with the this VM */
+	snprintf(path, sizeof(path),"/local/domain/0/backend/qdisk/%i", domid);
+	dev_ids = xs_directory(node->handle->xshandle, XBT_NULL, path, &num_dev_ids);
+	if (dev_ids == NULL) {
+		return;
+	}
+
+	/* Get the filename of the image associated with this QMP device */
+	image = qmp_get_block_image(node, qmp_devname, qfd);
+	if (image == NULL) {
+		free(dev_ids);
+		return;
+	}
+
+	/* Look for a matching image in xenstore */
+	for (i=0; i<num_dev_ids; i++) {
+		devid = atoi(dev_ids[i]);
+		/* Get the xenstore name of the image */
+		snprintf(path, sizeof(path),"/local/domain/0/backend/qdisk/%i/%i/params", domid, devid);
+		if ((ptr = xs_read(node->handle->xshandle, XBT_NULL, path, NULL)) == NULL)
+			continue;
+
+		/* Get to actual path in string */
+		if ((tmp = strchr(ptr, '/')) == NULL)
+			tmp = ptr;
+		if (!strcmp(tmp,image)) {
+			*dev = devid;
+			free(ptr);
+
+			/* Get the xenstore sector size of the image while we're here */
+			snprintf(path, sizeof(path),"/local/domain/0/backend/qdisk/%i/%i/sector-size", domid, devid);
+			if ((ptr = xs_read(node->handle->xshandle, XBT_NULL, path, NULL)) != NULL) {
+				*sector_size = atoi((char *)ptr);
+				free(ptr);
+			}
+			break;
+		}
+		free(ptr);
+	}
+
+	free(image);
+	free(dev_ids);
+}
+
+/* Parse the stats buffer which contains I/O data for all the disks belonging to domid */
+static void qmp_parse_stats(xenstat_node *node, unsigned int domid, unsigned char *stats_buf, int qfd)
+{
+	char *qmp_devname;
+	static const char *const qstats[] = {
+		[ QMP_STATS_RETURN  ] = "return",
+		[ QMP_STATS_DEVICE  ] = "device",
+		[ QMP_STATS         ] = "stats",
+		[ QMP_RD_BYTES      ] = "rd_bytes",
+		[ QMP_WR_BYTES      ] = "wr_bytes",
+		[ QMP_RD_OPERATIONS ] = "rd_operations",
+		[ QMP_WR_OPERATIONS ] = "wr_operations",
+	};
+	const char *ptr[] = {0, 0};
+	yajl_val info, ret_obj, stats_obj, n;
+	xenstat_vbd vbd;
+	xenstat_domain *domain;
+	unsigned int sector_size = 512;
+	int i, j;
+
+	/* Use libyajl version 2.0.3 or newer for the tree parser feature */
+	if ((info = yajl_tree_parse((char *)stats_buf, NULL, 0)) == NULL)
+		return;
+
+	ptr[0] = qstats[QMP_STATS_RETURN]; /* "return" */
+	if ((ret_obj = yajl_tree_get(info, ptr, yajl_t_array)) == NULL)
+		goto done;
+
+	/* Array of devices */
+	for (i=0; i<YAJL_GET_ARRAY(ret_obj)->len; i++) {
+		memset(&vbd, 0, sizeof(xenstat_vbd));
+		qmp_devname = NULL;
+		stats_obj = YAJL_GET_ARRAY(ret_obj)->values[i];
+
+		ptr[0] = qstats[QMP_STATS_DEVICE]; /* "device" */
+		if ((n = yajl_tree_get(stats_obj, ptr, yajl_t_any)) != NULL)
+			qmp_devname = YAJL_GET_STRING(n);
+
+		ptr[0] = qstats[QMP_STATS]; /* "stats" */
+		stats_obj = yajl_tree_get(stats_obj, ptr, yajl_t_object);
+		if (stats_obj && YAJL_IS_OBJECT(stats_obj)) {
+			for (j=3; j<7; j++) {
+				ptr[0] = qstats[j];
+				n = yajl_tree_get(stats_obj, ptr, yajl_t_number);
+				if (n && YAJL_IS_NUMBER(n)) {
+					switch(j) {
+					case QMP_RD_BYTES: /* "rd_bytes" */
+						vbd.rd_sects = YAJL_GET_INTEGER(n) / sector_size;
+						break;
+					case QMP_WR_BYTES: /* "wr_bytes" */
+						vbd.wr_sects = YAJL_GET_INTEGER(n) / sector_size;
+						break;
+					case QMP_RD_OPERATIONS: /* "rd_operations" */
+						vbd.rd_reqs = YAJL_GET_INTEGER(n);
+						break;
+					case QMP_WR_OPERATIONS: /* "wr_operations" */
+						vbd.wr_reqs = YAJL_GET_INTEGER(n);
+						break;
+					}
+				}
+			}
+			/* With the QMP device name, lookup the xenstore qdisk device ID and set vdb.dev */
+			if (qmp_devname)
+				lookup_xenstore_devid(node, domid, qmp_devname, qfd, &vbd.dev, &sector_size);
+			if ((domain = xenstat_node_domain(node, domid)) == NULL)
+				continue;
+			if ((xenstat_save_vbd(domain, &vbd)) == NULL)
+				goto done;
+		}
+	}
+done:
+	yajl_tree_free(info);
+}
+
+/* Write a command via the QMP. Returns number of bytes written */
+static size_t qmp_write(int qfd, char *cmd, size_t cmd_len)
+{
+	size_t pos = 0;
+	ssize_t res;
+
+	while (cmd_len > pos) {
+		res = write(qfd, cmd + pos, cmd_len - pos);
+		switch (res) {
+		case -1:
+			if (errno == EINTR || errno == EAGAIN)
+				continue;
+			return 0;
+		case 0:
+			errno = EPIPE;
+			return pos;
+		default:
+			pos += (size_t)res;
+		}
+	}
+	return pos;
+}
+
+/* Read the data sent in response to a QMP execute query. Returns 1 for success */
+static int qmp_read(int qfd, unsigned char **qstats)
+{
+	unsigned char buf[1024], *ptr;
+	struct pollfd pfd[2];
+	int n, qsize = 0;
+
+	*qstats = NULL;
+	pfd[0].fd = qfd;
+	pfd[0].events = POLLIN;
+	while ((n = poll(pfd, POLLIN, 10)) > 0) {
+		if (pfd[0].revents & POLLIN) {
+			if ((n = read(qfd, buf, sizeof(buf))) < 0) {
+				free(*qstats);
+				return 0;
+			}
+			ptr = realloc(*qstats, qsize+n+1);
+			if (ptr == NULL) {
+				free(*qstats);
+				return 0;
+			}
+			memcpy(&ptr[qsize], buf, n);
+			qsize += n;
+			ptr[qsize] = 0;
+			*qstats = ptr;
+		}
+	}
+	return 1;
+}
+
+/* With the given cmd, query QMP for requested data. Returns allocated buffer containing data or NULL */
+static unsigned char *qmp_query(int qfd, char *cmd)
+{
+	unsigned char *qstats = NULL;
+	int n;
+
+	n = strlen(cmd);
+	if (qmp_write(qfd, cmd, n) != n)
+		return NULL;
+	if (!qmp_read(qfd, &qstats))
+		return NULL;
+	return qstats;
+}
+
+/* Returns a socket connected to the QMP socket. Returns -1 on failure. */
+static int qmp_connect(char *path)
+{
+	struct sockaddr_un sun;
+	int s;
+
+	if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+		return -1;
+	(void)fcntl(s, F_SETFD, 1);
+
+	memset(&sun, 0, sizeof(struct sockaddr_un));
+	sun.sun_family = AF_UNIX;
+
+	if (strlen(path) >= sizeof(sun.sun_path)) {
+		close(s);
+		return -1;
+	}
+
+	strcpy(sun.sun_path, path);
+	if (connect(s, (struct sockaddr *)&sun, SUN_LEN(&sun)) < 0) {
+		close(s);
+		return -1;
+	}
+
+	return s;
+}
+
+/* Get up to 1024 active domains */
+static xc_domaininfo_t *get_domain_ids(int *num_doms)
+{
+	xc_domaininfo_t *dominfo;
+	xc_interface *xc_handle;
+
+	dominfo = calloc(1024, sizeof(xc_domaininfo_t));
+	if (dominfo == NULL)
+		return NULL;
+	xc_handle = xc_interface_open(0,0,0);
+	*num_doms = xc_domain_getinfolist(xc_handle, 0, 1024, dominfo);
+	xc_interface_close(xc_handle);
+	return dominfo;
+}
+
+/* Gather the qdisk statistics by querying QMP
+   Resources: http://wiki.qemu.org/QMP and qmp-commands.hx from the qemu code
+   QMP Syntax for entering command mode. This command must be issued before
+   issuing any other command:
+     In: {"execute": "qmp_capabilities"}
+     Out: {"return": {}}
+   QMP Syntax for querying block statistics:
+     In: { "execute": "query-blockstats" }
+     Out: {"return": [{
+            "device": 'str',
+            "parent": {
+              "stats": {
+                "flush_total_time_ns": 'int', "wr_highest_offset": 'int',
+                "wr_total_time_ns": 'int', "wr_bytes": 'int',
+                "rd_total_time_ns": 'int', "flush_operations": 'int',
+                "wr_operations": 'int', "rd_bytes": 'int', "rd_operations": 'int'
+              }
+            },
+            "stats": {
+              "flush_total_time_ns": 'int', "wr_highest_offset": 'int',
+              "wr_total_time_ns": 'int', "wr_bytes": 'int',
+              "rd_total_time_ns": 'int', "flush_operations": 'int',
+              "wr_operations": 'int', "rd_bytes": 'int', "rd_operations": 'int'
+            }
+          }]}
+*/
+void read_attributes_qdisk(xenstat_node * node)
+{
+	char *cmd_mode = "{ \"execute\": \"qmp_capabilities\" }";
+	char *query_blockstats_cmd = "{ \"execute\": \"query-blockstats\" }";
+	xc_domaininfo_t *dominfo = NULL;
+	unsigned char *qmp_stats, *val;
+	char path[80];
+	int i, qfd, num_doms;
+
+	dominfo = get_domain_ids(&num_doms);
+	if (dominfo == NULL)
+		return;
+
+	for (i=0; i<num_doms; i++) {
+		if (dominfo[i].domain <= 0)
+			continue;
+
+		/* Verify that qdisk disks are used with this VM */
+		snprintf(path, sizeof(path),"/local/domain/0/backend/qdisk/%i", dominfo[i].domain);
+		if ((val = xs_read(node->handle->xshandle, XBT_NULL, path, NULL)) == NULL)
+			continue;
+		free(val);
+
+		/* Connect to this VMs QMP socket */
+		snprintf(path, sizeof(path), "/var/run/xen/qmp-libxenstat-%i", dominfo[i].domain);
+		if ((qfd = qmp_connect(path)) < 0) {
+			continue;
+		}
+
+		/* First enable QMP capabilities so that we can query for data */
+		if ((qmp_stats = qmp_query(qfd, cmd_mode)) != NULL) {
+			free(qmp_stats);
+			/* Query QMP for this VMs blockstats */
+			if ((qmp_stats = qmp_query(qfd, query_blockstats_cmd)) != NULL) {
+				qmp_parse_stats(node, dominfo[i].domain, qmp_stats, qfd);
+				free(qmp_stats);
+			}
+		}
+		close(qfd);
+	}
+
+	free(dominfo);
+}
+
+#else /* !HAVE_YAJL_V2 */
+
+/* Statistics gathering for qdisks requires at least yajl v2 */
+void read_attributes_qdisk(xenstat_node * node)
+{
+}
+
+#endif /* !HAVE_YAJL_V2 */