xen: backend driver core (Gerd Hoffmann) (d94f9486) · Commits · SUMMER2020 / students / proj-2021291

Makefile.target

+1 −1

Original line number	Diff line number	Diff line
		@@ -561,7 +561,7 @@ LIBS += $(CONFIG_BLUEZ_LIBS)
		endif

		# xen backend driver support
		XEN_OBJS := xen_machine_pv.o
		XEN_OBJS := xen_machine_pv.o xen_backend.o
		ifeq ($(CONFIG_XEN), yes)
		OBJS += $(XEN_OBJS)
		LIBS += $(XEN_LIBS)

hw/xen_backend.c

0 → 100644

+713 −0

Original line number	Diff line number	Diff line
		/*
		* xen backend driver infrastructure
		* (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; under version 2 of the License.
		*
		* 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 General Public License for more details.
		*
		* You should have received a copy of the GNU General Public License along
		* with this program; if not, write to the Free Software Foundation, Inc.,
		* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
		*/

		/*
		* TODO: add some xenbus / xenstore concepts overview here.
		*/

		#include <stdio.h>
		#include <stdlib.h>
		#include <stdarg.h>
		#include <string.h>
		#include <unistd.h>
		#include <fcntl.h>
		#include <inttypes.h>
		#include <sys/types.h>
		#include <sys/stat.h>
		#include <sys/mman.h>
		#include <sys/signal.h>

		#include <xs.h>
		#include <xenctrl.h>
		#include <xen/grant_table.h>

		#include "hw.h"
		#include "qemu-char.h"
		#include "xen_backend.h"

		/* ------------------------------------------------------------- */

		/* public */
		int xen_xc;
		struct xs_handle *xenstore = NULL;

		/* private */
		static TAILQ_HEAD(XenDeviceHead, XenDevice) xendevs = TAILQ_HEAD_INITIALIZER(xendevs);
		static int debug = 0;

		/* ------------------------------------------------------------- */

		int xenstore_write_str(const char base, const char node, const char *val)
		{
		char abspath[XEN_BUFSIZE];

		snprintf(abspath, sizeof(abspath), "%s/%s", base, node);
		if (!xs_write(xenstore, 0, abspath, val, strlen(val)))
		return -1;
		return 0;
		}

		char xenstore_read_str(const char base, const char *node)
		{
		char abspath[XEN_BUFSIZE];
		unsigned int len;
		char str, ret = NULL;

		snprintf(abspath, sizeof(abspath), "%s/%s", base, node);
		str = xs_read(xenstore, 0, abspath, &len);
		if (str != NULL) {
		/* move to qemu-allocated memory to make sure
		* callers can savely qemu_free() stuff. */
		ret = qemu_strdup(str);
		free(str);
		}
		return ret;
		}

		int xenstore_write_int(const char base, const char node, int ival)
		{
		char val[32];

		snprintf(val, sizeof(val), "%d", ival);
		return xenstore_write_str(base, node, val);
		}

		int xenstore_read_int(const char base, const char node, int *ival)
		{
		char *val;
		int rc = -1;

		val = xenstore_read_str(base, node);
		if (val && 1 == sscanf(val, "%d", ival))
		rc = 0;
		qemu_free(val);
		return rc;
		}

		int xenstore_write_be_str(struct XenDevice xendev, const char node, const char *val)
		{
		return xenstore_write_str(xendev->be, node, val);
		}

		int xenstore_write_be_int(struct XenDevice xendev, const char node, int ival)
		{
		return xenstore_write_int(xendev->be, node, ival);
		}

		char xenstore_read_be_str(struct XenDevice xendev, const char *node)
		{
		return xenstore_read_str(xendev->be, node);
		}

		int xenstore_read_be_int(struct XenDevice xendev, const char node, int *ival)
		{
		return xenstore_read_int(xendev->be, node, ival);
		}

		char xenstore_read_fe_str(struct XenDevice xendev, const char *node)
		{
		return xenstore_read_str(xendev->fe, node);
		}

		int xenstore_read_fe_int(struct XenDevice xendev, const char node, int *ival)
		{
		return xenstore_read_int(xendev->fe, node, ival);
		}

		/* ------------------------------------------------------------- */

		const char *xenbus_strstate(enum xenbus_state state)
		{
		static const char *const name[] = {
		[ XenbusStateUnknown ] = "Unknown",
		[ XenbusStateInitialising ] = "Initialising",
		[ XenbusStateInitWait ] = "InitWait",
		[ XenbusStateInitialised ] = "Initialised",
		[ XenbusStateConnected ] = "Connected",
		[ XenbusStateClosing ] = "Closing",
		[ XenbusStateClosed ] = "Closed",
		};
		return (state < ARRAY_SIZE(name)) ? name[state] : "INVALID";
		}

		int xen_be_set_state(struct XenDevice *xendev, enum xenbus_state state)
		{
		int rc;

		rc = xenstore_write_be_int(xendev, "state", state);
		if (rc < 0)
		return rc;
		xen_be_printf(xendev, 1, "backend state: %s -> %s\n",
		xenbus_strstate(xendev->be_state), xenbus_strstate(state));
		xendev->be_state = state;
		return 0;
		}

		/* ------------------------------------------------------------- */

		struct XenDevice xen_be_find_xendev(const char type, int dom, int dev)
		{
		struct XenDevice *xendev;

		TAILQ_FOREACH(xendev, &xendevs, next) {
		if (xendev->dom != dom)
		continue;
		if (xendev->dev != dev)
		continue;
		if (strcmp(xendev->type, type) != 0)
		continue;
		return xendev;
		}
		return NULL;
		}

		/*
		* get xen backend device, allocate a new one if it doesn't exist.
		*/
		static struct XenDevice xen_be_get_xendev(const char type, int dom, int dev,
		struct XenDevOps *ops)
		{
		struct XenDevice *xendev;
		char *dom0;

		xendev = xen_be_find_xendev(type, dom, dev);
		if (xendev)
		return xendev;

		/* init new xendev */
		xendev = qemu_mallocz(ops->size);
		xendev->type = type;
		xendev->dom = dom;
		xendev->dev = dev;
		xendev->ops = ops;

		dom0 = xs_get_domain_path(xenstore, 0);
		snprintf(xendev->be, sizeof(xendev->be), "%s/backend/%s/%d/%d",
		dom0, xendev->type, xendev->dom, xendev->dev);
		snprintf(xendev->name, sizeof(xendev->name), "%s-%d",
		xendev->type, xendev->dev);
		free(dom0);

		xendev->debug = debug;
		xendev->local_port = -1;

		xendev->evtchndev = xc_evtchn_open();
		if (xendev->evtchndev < 0) {
		xen_be_printf(NULL, 0, "can't open evtchn device\n");
		qemu_free(xendev);
		return NULL;
		}
		fcntl(xc_evtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);

		if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
		xendev->gnttabdev = xc_gnttab_open();
		if (xendev->gnttabdev < 0) {
		xen_be_printf(NULL, 0, "can't open gnttab device\n");
		xc_evtchn_close(xendev->evtchndev);
		qemu_free(xendev);
		return NULL;
		}
		} else {
		xendev->gnttabdev = -1;
		}

		TAILQ_INSERT_TAIL(&xendevs, xendev, next);

		if (xendev->ops->alloc)
		xendev->ops->alloc(xendev);

		return xendev;
		}

		/*
		* release xen backend device.
		*/
		static struct XenDevice *xen_be_del_xendev(int dom, int dev)
		{
		struct XenDevice xendev, xnext;

		/*
		* This is pretty much like TAILQ_FOREACH(xendev, &xendevs, next) but
		* we save the next pointer in xnext because we might free xendev.
		*/
		xnext = xendevs.tqh_first;
		while (xnext) {
		xendev = xnext;
		xnext = xendev->next.tqe_next;

		if (xendev->dom != dom)
		continue;
		if (xendev->dev != dev && dev != -1)
		continue;

		if (xendev->ops->free)
		xendev->ops->free(xendev);

		if (xendev->fe) {
		char token[XEN_BUFSIZE];
		snprintf(token, sizeof(token), "fe:%p", xendev);
		xs_unwatch(xenstore, xendev->fe, token);
		qemu_free(xendev->fe);
		}

		if (xendev->evtchndev >= 0)
		xc_evtchn_close(xendev->evtchndev);
		if (xendev->gnttabdev >= 0)
		xc_gnttab_close(xendev->gnttabdev);

		TAILQ_REMOVE(&xendevs, xendev, next);
		qemu_free(xendev);
		}
		return NULL;
		}

		/*
		* Sync internal data structures on xenstore updates.
		* Node specifies the changed field. node = NULL means
		* update all fields (used for initialization).
		*/
		static void xen_be_backend_changed(struct XenDevice xendev, const char node)
		{
		if (node == NULL \|\| strcmp(node, "online") == 0) {
		if (xenstore_read_be_int(xendev, "online", &xendev->online) == -1)
		xendev->online = 0;
		}

		if (node) {
		xen_be_printf(xendev, 2, "backend update: %s\n", node);
		if (xendev->ops->backend_changed)
		xendev->ops->backend_changed(xendev, node);
		}
		}

		static void xen_be_frontend_changed(struct XenDevice xendev, const char node)
		{
		int fe_state;

		if (node == NULL \|\| strcmp(node, "state") == 0) {
		if (xenstore_read_fe_int(xendev, "state", &fe_state) == -1)
		fe_state = XenbusStateUnknown;
		if (xendev->fe_state != fe_state)
		xen_be_printf(xendev, 1, "frontend state: %s -> %s\n",
		xenbus_strstate(xendev->fe_state),
		xenbus_strstate(fe_state));
		xendev->fe_state = fe_state;
		}
		if (node == NULL \|\| strcmp(node, "protocol") == 0) {
		qemu_free(xendev->protocol);
		xendev->protocol = xenstore_read_fe_str(xendev, "protocol");
		if (xendev->protocol)
		xen_be_printf(xendev, 1, "frontend protocol: %s\n", xendev->protocol);
		}

		if (node) {
		xen_be_printf(xendev, 2, "frontend update: %s\n", node);
		if (xendev->ops->frontend_changed)
		xendev->ops->frontend_changed(xendev, node);
		}
		}

		/* ------------------------------------------------------------- */
		/* Check for possible state transitions and perform them. */

		/*
		* Initial xendev setup. Read frontend path, register watch for it.
		* Should succeed once xend finished setting up the backend device.
		*
		* Also sets initial state (-> Initializing) when done. Which
		* only affects the xendev->be_state variable as xenbus should
		* already be put into that state by xend.
		*/
		static int xen_be_try_setup(struct XenDevice *xendev)
		{
		char token[XEN_BUFSIZE];
		int be_state;

		if (xenstore_read_be_int(xendev, "state", &be_state) == -1) {
		xen_be_printf(xendev, 0, "reading backend state failed\n");
		return -1;
		}

		if (be_state != XenbusStateInitialising) {
		xen_be_printf(xendev, 0, "initial backend state is wrong (%s)\n",
		xenbus_strstate(be_state));
		return -1;
		}

		xendev->fe = xenstore_read_be_str(xendev, "frontend");
		if (xendev->fe == NULL) {
		xen_be_printf(xendev, 0, "reading frontend path failed\n");
		return -1;
		}

		/* setup frontend watch */
		snprintf(token, sizeof(token), "fe:%p", xendev);
		if (!xs_watch(xenstore, xendev->fe, token)) {
		xen_be_printf(xendev, 0, "watching frontend path (%s) failed\n",
		xendev->fe);
		return -1;
		}
		xen_be_set_state(xendev, XenbusStateInitialising);

		xen_be_backend_changed(xendev, NULL);
		xen_be_frontend_changed(xendev, NULL);
		return 0;
		}

		/*
		* Try initialize xendev. Prepare everything the backend can do
		* without synchronizing with the frontend. Fakes hotplug-status. No
		* hotplug involved here because this is about userspace drivers, thus
		* there are kernel backend devices which could invoke hotplug.
		*
		* Goes to InitWait on success.
		*/
		static int xen_be_try_init(struct XenDevice *xendev)
		{
		int rc = 0;

		if (!xendev->online) {
		xen_be_printf(xendev, 1, "not online\n");
		return -1;
		}

		if (xendev->ops->init)
		rc = xendev->ops->init(xendev);
		if (rc != 0) {
		xen_be_printf(xendev, 1, "init() failed\n");
		return rc;
		}

		xenstore_write_be_str(xendev, "hotplug-status", "connected");
		xen_be_set_state(xendev, XenbusStateInitWait);
		return 0;
		}

		/*
		* Try to connect xendev. Depends on the frontend being ready
		* for it (shared ring and evtchn info in xenstore, state being
		* Initialised or Connected).
		*
		* Goes to Connected on success.
		*/
		static int xen_be_try_connect(struct XenDevice *xendev)
		{
		int rc = 0;

		if (xendev->fe_state != XenbusStateInitialised &&
		xendev->fe_state != XenbusStateConnected) {
		if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
		xen_be_printf(xendev, 2, "frontend not ready, ignoring\n");
		} else {
		xen_be_printf(xendev, 2, "frontend not ready (yet)\n");
		return -1;
		}
		}

		if (xendev->ops->connect)
		rc = xendev->ops->connect(xendev);
		if (rc != 0) {
		xen_be_printf(xendev, 0, "connect() failed\n");
		return rc;
		}

		xen_be_set_state(xendev, XenbusStateConnected);
		return 0;
		}

		/*
		* Teardown connection.
		*
		* Goes to Closed when done.
		*/
		static void xen_be_disconnect(struct XenDevice *xendev, enum xenbus_state state)
		{
		if (xendev->be_state != XenbusStateClosing &&
		xendev->be_state != XenbusStateClosed &&
		xendev->ops->disconnect)
		xendev->ops->disconnect(xendev);
		if (xendev->be_state != state)
		xen_be_set_state(xendev, state);
		}

		/*
		* Try to reset xendev, for reconnection by another frontend instance.
		*/
		static int xen_be_try_reset(struct XenDevice *xendev)
		{
		if (xendev->fe_state != XenbusStateInitialising)
		return -1;

		xen_be_printf(xendev, 1, "device reset (for re-connect)\n");
		xen_be_set_state(xendev, XenbusStateInitialising);
		return 0;
		}

		/*
		* state change dispatcher function
		*/
		void xen_be_check_state(struct XenDevice *xendev)
		{
		int rc = 0;

		/* frontend may request shutdown from almost anywhere */
		if (xendev->fe_state == XenbusStateClosing \|\|
		xendev->fe_state == XenbusStateClosed) {
		xen_be_disconnect(xendev, xendev->fe_state);
		return;
		}

		/* check for possible backend state transitions */
		for (;;) {
		switch (xendev->be_state) {
		case XenbusStateUnknown:
		rc = xen_be_try_setup(xendev);
		break;
		case XenbusStateInitialising:
		rc = xen_be_try_init(xendev);
		break;
		case XenbusStateInitWait:
		rc = xen_be_try_connect(xendev);
		break;
		case XenbusStateClosed:
		rc = xen_be_try_reset(xendev);
		break;
		default:
		rc = -1;
		}
		if (rc != 0)
		break;
		}
		}

		/* ------------------------------------------------------------- */

		static int xenstore_scan(const char type, int dom, struct XenDevOps ops)
		{
		struct XenDevice *xendev;
		char path[XEN_BUFSIZE], token[XEN_BUFSIZE];
		char *dev = NULL, dom0;
		unsigned int cdev, j;

		/* setup watch */
		dom0 = xs_get_domain_path(xenstore, 0);
		snprintf(token, sizeof(token), "be:%p:%d:%p", type, dom, ops);
		snprintf(path, sizeof(path), "%s/backend/%s/%d", dom0, type, dom);
		free(dom0);
		if (!xs_watch(xenstore, path, token)) {
		xen_be_printf(NULL, 0, "xen be: watching backend path (%s) failed\n", path);
		return -1;
		}

		/* look for backends */
		dev = xs_directory(xenstore, 0, path, &cdev);
		if (!dev)
		return 0;
		for (j = 0; j < cdev; j++) {
		xendev = xen_be_get_xendev(type, dom, atoi(dev[j]), ops);
		if (xendev == NULL)
		continue;
		xen_be_check_state(xendev);
		}
		free(dev);
		return 0;
		}

		static void xenstore_update_be(char watch, char type, int dom,
		struct XenDevOps *ops)
		{
		struct XenDevice *xendev;
		char path[XEN_BUFSIZE], *dom0;
		unsigned int len, dev;

		dom0 = xs_get_domain_path(xenstore, 0);
		len = snprintf(path, sizeof(path), "%s/backend/%s/%d", dom0, type, dom);
		free(dom0);
		if (strncmp(path, watch, len) != 0)
		return;
		if (sscanf(watch+len, "/%u/%255s", &dev, path) != 2) {
		strcpy(path, "");
		if (sscanf(watch+len, "/%u", &dev) != 1)
		dev = -1;
		}
		if (dev == -1)
		return;

		if (0) {
		/* FIXME: detect devices being deleted from xenstore ... */
		xen_be_del_xendev(dom, dev);
		}

		xendev = xen_be_get_xendev(type, dom, dev, ops);
		if (xendev != NULL) {
		xen_be_backend_changed(xendev, path);
		xen_be_check_state(xendev);
		}
		}

		static void xenstore_update_fe(char watch, struct XenDevice xendev)
		{
		char *node;
		unsigned int len;

		len = strlen(xendev->fe);
		if (strncmp(xendev->fe, watch, len) != 0)
		return;
		if (watch[len] != '/')
		return;
		node = watch + len + 1;

		xen_be_frontend_changed(xendev, node);
		xen_be_check_state(xendev);
		}

		static void xenstore_update(void *unused)
		{
		char **vec = NULL;
		intptr_t type, ops, ptr;
		unsigned int dom, count;

		vec = xs_read_watch(xenstore, &count);
		if (vec == NULL)
		goto cleanup;

		if (sscanf(vec[XS_WATCH_TOKEN], "be:%" PRIxPTR ":%d:%" PRIxPTR,
		&type, &dom, &ops) == 3)
		xenstore_update_be(vec[XS_WATCH_PATH], (void)type, dom, (void)ops);
		if (sscanf(vec[XS_WATCH_TOKEN], "fe:%" PRIxPTR, &ptr) == 1)
		xenstore_update_fe(vec[XS_WATCH_PATH], (void*)ptr);

		cleanup:
		qemu_free(vec);
		}

		static void xen_be_evtchn_event(void *opaque)
		{
		struct XenDevice *xendev = opaque;
		evtchn_port_t port;

		port = xc_evtchn_pending(xendev->evtchndev);
		if (port != xendev->local_port) {
		xen_be_printf(xendev, 0, "xc_evtchn_pending returned %d (expected %d)\n",
		port, xendev->local_port);
		return;
		}
		xc_evtchn_unmask(xendev->evtchndev, port);

		if (xendev->ops->event)
		xendev->ops->event(xendev);
		}

		/* -------------------------------------------------------------------- */

		int xen_be_init(void)
		{
		xenstore = xs_daemon_open();
		if (!xenstore) {
		xen_be_printf(NULL, 0, "can't connect to xenstored\n");
		return -1;
		}

		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_be_printf(NULL, 0, "can't open xen interface\n");
		goto err;
		}
		return 0;

		err:
		qemu_set_fd_handler(xs_fileno(xenstore), NULL, NULL, NULL);
		xs_daemon_close(xenstore);
		xenstore = NULL;

		return -1;
		}

		int xen_be_register(const char type, struct XenDevOps ops)
		{
		return xenstore_scan(type, xen_domid, ops);
		}

		int xen_be_bind_evtchn(struct XenDevice *xendev)
		{
		if (xendev->local_port != -1)
		return 0;
		xendev->local_port = xc_evtchn_bind_interdomain
		(xendev->evtchndev, xendev->dom, xendev->remote_port);
		if (xendev->local_port == -1) {
		xen_be_printf(xendev, 0, "xc_evtchn_bind_interdomain failed\n");
		return -1;
		}
		xen_be_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
		qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev),
		xen_be_evtchn_event, NULL, xendev);
		return 0;
		}

		void xen_be_unbind_evtchn(struct XenDevice *xendev)
		{
		if (xendev->local_port == -1)
		return;
		qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev), NULL, NULL, NULL);
		xc_evtchn_unbind(xendev->evtchndev, xendev->local_port);
		xen_be_printf(xendev, 2, "unbind evtchn port %d\n", xendev->local_port);
		xendev->local_port = -1;
		}

		int xen_be_send_notify(struct XenDevice *xendev)
		{
		return xc_evtchn_notify(xendev->evtchndev, xendev->local_port);
		}

		/*
		* msg_level:
		* 0 == errors (stderr + logfile).
		* 1 == informative debug messages (logfile only).
		* 2 == noisy debug messages (logfile only).
		* 3 == will flood your log (logfile only).
		*/
		void xen_be_printf(struct XenDevice xendev, int msg_level, const char fmt, ...)
		{
		va_list args;

		if (xendev) {
		if (msg_level > xendev->debug)
		return;
		qemu_log("xen be: %s: ", xendev->name);
		if (msg_level == 0)
		fprintf(stderr, "xen be: %s: ", xendev->name);
		} else {
		if (msg_level > debug)
		return;
		qemu_log("xen be core: ");
		if (msg_level == 0)
		fprintf(stderr, "xen be core: ");
		}
		va_start(args, fmt);
		qemu_log_vprintf(fmt, args);
		va_end(args);
		if (msg_level == 0) {
		va_start(args, fmt);
		vfprintf(stderr, fmt, args);
		va_end(args);
		}
		qemu_log_flush();
		}

hw/xen_backend.h

0 → 100644

+86 −0

Original line number	Diff line number	Diff line
		#ifndef QEMU_HW_XEN_BACKEND_H
		#define QEMU_HW_XEN_BACKEND_H 1

		#include "xen_common.h"

		/* ------------------------------------------------------------- */

		#define XEN_BUFSIZE 1024

		struct XenDevice;

		/* driver uses grant tables -> open gntdev device (xendev->gnttabdev) */
		#define DEVOPS_FLAG_NEED_GNTDEV 1
		/* don't expect frontend doing correct state transitions (aka console quirk) */
		#define DEVOPS_FLAG_IGNORE_STATE 2

		struct XenDevOps {
		size_t size;
		uint32_t flags;
		void (alloc)(struct XenDevice xendev);
		int (init)(struct XenDevice xendev);
		int (connect)(struct XenDevice xendev);
		void (event)(struct XenDevice xendev);
		void (disconnect)(struct XenDevice xendev);
		int (free)(struct XenDevice xendev);
		void (backend_changed)(struct XenDevice xendev, const char *node);
		void (frontend_changed)(struct XenDevice xendev, const char *node);
		};

		struct XenDevice {
		const char *type;
		int dom;
		int dev;
		char name[64];
		int debug;

		enum xenbus_state be_state;
		enum xenbus_state fe_state;
		int online;
		char be[XEN_BUFSIZE];
		char *fe;
		char *protocol;
		int remote_port;
		int local_port;

		int evtchndev;
		int gnttabdev;

		struct XenDevOps *ops;
		TAILQ_ENTRY(XenDevice) next;
		};

		/* ------------------------------------------------------------- */

		/* variables */
		extern int xen_xc;
		extern struct xs_handle *xenstore;

		/* xenstore helper functions */
		int xenstore_write_str(const char base, const char node, const char *val);
		int xenstore_write_int(const char base, const char node, int ival);
		char xenstore_read_str(const char base, const char *node);
		int xenstore_read_int(const char base, const char node, int *ival);

		int xenstore_write_be_str(struct XenDevice xendev, const char node, const char *val);
		int xenstore_write_be_int(struct XenDevice xendev, const char node, int ival);
		char xenstore_read_be_str(struct XenDevice xendev, const char *node);
		int xenstore_read_be_int(struct XenDevice xendev, const char node, int *ival);
		char xenstore_read_fe_str(struct XenDevice xendev, const char *node);
		int xenstore_read_fe_int(struct XenDevice xendev, const char node, int *ival);

		const char *xenbus_strstate(enum xenbus_state state);
		struct XenDevice xen_be_find_xendev(const char type, int dom, int dev);
		void xen_be_check_state(struct XenDevice *xendev);

		/* xen backend driver bits */
		int xen_be_init(void);
		int xen_be_register(const char type, struct XenDevOps ops);
		int xen_be_set_state(struct XenDevice *xendev, enum xenbus_state state);
		int xen_be_bind_evtchn(struct XenDevice *xendev);
		void xen_be_unbind_evtchn(struct XenDevice *xendev);
		int xen_be_send_notify(struct XenDevice *xendev);
		void xen_be_printf(struct XenDevice xendev, int msg_level, const char fmt, ...)
		__attribute__ ((format(printf, 3, 4)));

		#endif /* QEMU_HW_XEN_BACKEND_H */

hw/xen_common.h

0 → 100644

+34 −0

Original line number	Diff line number	Diff line
		#ifndef QEMU_HW_XEN_COMMON_H
		#define QEMU_HW_XEN_COMMON_H 1

		#include <stddef.h>
		#include <inttypes.h>

		#include <xenctrl.h>
		#include <xs.h>
		#include <xen/io/xenbus.h>

		#include "hw.h"
		#include "xen.h"
		#include "sys-queue.h" /* BSD list implementation */

		/*
		* tweaks needed to build with different xen versions
		* 0x00030205 -> 3.1.0
		* 0x00030207 -> 3.2.0
		* 0x00030208 -> unstable
		*/
		#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()
		#endif

		#endif /* QEMU_HW_XEN_COMMON_H */

hw/xen_machine_pv.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -26,7 +26,7 @@
		#include "pc.h"
		#include "sysemu.h"
		#include "boards.h"
		#include "xen.h"
		#include "xen_backend.h"

		uint32_t xen_domid;
		enum xen_mode xen_mode = XEN_EMULATE;
		@@ -50,6 +50,12 @@ static void xen_init_pv(ram_addr_t ram_size, int vga_ram_size,
		}
		env = cpu_init(cpu_model);
		env->halted = 1;

		/* Initialize backend core & drivers */
		if (xen_be_init() != 0) {
		fprintf(stderr, "%s: xen backend core setup failed\n", __FUNCTION__);
		exit(1);
		}
		}

		QEMUMachine xenpv_machine = {