Have xenstored initialise its connections, meaning that xend can be out of

that loop completely -- the xc_init_store, initDomainStore calls can all go.

Have xenstored understand where the local domain information goes.  Xend no
longer has to generate a path and pass it to xenstored through
xs_introduce_domain -- we just allow xenstored to generate the path, and then
call GetDomainPath later.  There is still some work required to tidy this up.

Change the uuid module to generate uuids as lists of bytes, not in the
stringified form.  Added a unit test for that module.

Change the semantics of Xend restart, relying on these changes to the
xenstored semantics and earlier changes to add an opaque handle to the
hypervisor's domain-specific data block.  The semantics are now clearer, as
Xend can validate whether the details in the store match the current live
domain.

Added a usage statement to xenstored.

Some of this code is by Steven Hand.

Signed-off-by: Ewan Mellor <ewan@xensource.com>

1 files changed, 58 insertions, 20 deletions

diff --git a/tools/xenstore/xenstored_domain.c b/tools/xenstore/xenstored_domain.c
index 74558b1ec9..9ddcf4f728 100644
--- a/tools/xenstore/xenstored_domain.c
+++ b/tools/xenstore/xenstored_domain.c
@@ -40,9 +40,10 @@
 #include <xen/linux/evtchn.h>
 
 static int *xc_handle;
-static int eventchn_fd;
 static int virq_port;
 
+int eventchn_fd = -1; 
+
 struct domain
 {
 	struct list_head list;
@@ -79,9 +80,11 @@ static LIST_HEAD(domains);
 #ifndef TESTING
 static void evtchn_notify(int port)
 {
+	int rc; 
+
 	struct ioctl_evtchn_notify notify;
 	notify.port = port;
-	(void)ioctl(event_fd, IOCTL_EVTCHN_NOTIFY, &notify);
+	rc = ioctl(eventchn_fd, IOCTL_EVTCHN_NOTIFY, &notify);
 }
 #else
 extern void evtchn_notify(int port);
@@ -222,14 +225,14 @@ void handle_event(void)
 {
 	uint16_t port;
 
-	if (read(event_fd, &port, sizeof(port)) != sizeof(port))
+	if (read(eventchn_fd, &port, sizeof(port)) != sizeof(port))
 		barf_perror("Failed to read from event fd");
 
 	if (port == virq_port)
 		domain_cleanup();
 
 #ifndef TESTING
-	if (write(event_fd, &port, sizeof(port)) != sizeof(port))
+	if (write(eventchn_fd, &port, sizeof(port)) != sizeof(port))
 		barf_perror("Failed to write to event fd");
 #endif
 }
@@ -247,18 +250,18 @@ bool domain_can_write(struct connection *conn)
 }
 
 static struct domain *new_domain(void *context, unsigned int domid,
-				 unsigned long mfn, int port,
-				 const char *path)
+				 unsigned long mfn, int port)
 {
 	struct domain *domain;
 	struct ioctl_evtchn_bind_interdomain bind;
 	int rc;
 
+
 	domain = talloc(context, struct domain);
 	domain->port = 0;
 	domain->shutdown = 0;
 	domain->domid = domid;
-	domain->path = talloc_strdup(domain, path);
+	domain->path = talloc_asprintf(domain, "/local/domain/%d", domid);
 	domain->interface = xc_map_foreign_range(
 		*xc_handle, domain->domid,
 		getpagesize(), PROT_READ|PROT_WRITE, mfn);
@@ -269,13 +272,13 @@ static struct domain *new_domain(void *context, unsigned int domid,
 	talloc_set_destructor(domain, destroy_domain);
 
 	/* Tell kernel we're interested in this event. */
-	bind.remote_domain = domid;
-	bind.remote_port   = port;
-	rc = ioctl(eventchn_fd, IOCTL_EVTCHN_BIND_INTERDOMAIN, &bind);
-	if (rc == -1)
-		return NULL;
+        bind.remote_domain = domid;
+        bind.remote_port   = port;
+        rc = ioctl(eventchn_fd, IOCTL_EVTCHN_BIND_INTERDOMAIN, &bind);
+        if (rc == -1)
+            return NULL;
+        domain->port = rc;
 
-	domain->port = rc;
 	domain->conn = new_connection(writechn, readchn);
 	domain->conn->domain = domain;
 
@@ -302,11 +305,10 @@ static struct domain *find_domain_by_domid(unsigned int domid)
 void do_introduce(struct connection *conn, struct buffered_data *in)
 {
 	struct domain *domain;
-	char *vec[4];
+	char *vec[3];
 	unsigned int domid;
 	unsigned long mfn;
 	uint16_t port;
-	const char *path;
 
 	if (get_strings(in, vec, ARRAY_SIZE(vec)) < ARRAY_SIZE(vec)) {
 		send_error(conn, EINVAL);
@@ -321,10 +323,9 @@ void do_introduce(struct connection *conn, struct buffered_data *in)
 	domid = atoi(vec[0]);
 	mfn = atol(vec[1]);
 	port = atoi(vec[2]);
-	path = vec[3];
 
 	/* Sanity check args. */
-	if ((port <= 0) || !is_valid_nodename(path)) {
+	if (port <= 0) { 
 		send_error(conn, EINVAL);
 		return;
 	}
@@ -333,7 +334,7 @@ void do_introduce(struct connection *conn, struct buffered_data *in)
 
 	if (domain == NULL) {
 		/* Hang domain off "in" until we're finished. */
-		domain = new_domain(in, domid, mfn, port, path);
+		domain = new_domain(in, domid, mfn, port);
 		if (!domain) {
 			send_error(conn, errno);
 			return;
@@ -348,8 +349,7 @@ void do_introduce(struct connection *conn, struct buffered_data *in)
 		/* Check that the given details match the ones we have
 		   previously recorded. */
 		if (port != domain->remote_port ||
-		    mfn != domain->mfn ||
-		    strcmp(path, domain->path) != 0) {
+		    mfn != domain->mfn) {
 			send_error(conn, EINVAL);
 			return;
 		}
@@ -440,10 +440,45 @@ void restore_existing_connections(void)
 {
 }
 
+static int dom0_init(void) 
+{ 
+        int rc, fd, port; 
+        unsigned long mfn; 
+        char str[20]; 
+        struct domain *dom0; 
+        
+        fd = open("/proc/xen/xsd_mfn", O_RDONLY); 
+        
+        rc = read(fd, str, sizeof(str)); 
+        str[rc] = '\0'; 
+        mfn = strtoul(str, NULL, 0); 
+        
+        close(fd); 
+        
+        fd = open("/proc/xen/xsd_port", O_RDONLY); 
+        
+        rc = read(fd, str, sizeof(str)); 
+        str[rc] = '\0'; 
+        port = strtoul(str, NULL, 0); 
+        
+        close(fd); 
+        
+        
+        dom0 = new_domain(NULL, 0, mfn, port); 
+        talloc_steal(dom0->conn, dom0); 
+
+        evtchn_notify(dom0->port); 
+
+        return 0; 
+}
+
+
+
 #define EVTCHN_DEV_NAME  "/dev/xen/evtchn"
 #define EVTCHN_DEV_MAJOR 10
 #define EVTCHN_DEV_MINOR 201
 
+
 /* Returns the event channel handle. */
 int domain_init(void)
 {
@@ -484,6 +519,9 @@ int domain_init(void)
 	if (eventchn_fd < 0)
 		barf_perror("Failed to open evtchn device");
 
+        if (dom0_init() != 0) 
+                barf_perror("Failed to initialize dom0 state"); 
+     
 	bind.virq = VIRQ_DOM_EXC;
 	rc = ioctl(eventchn_fd, IOCTL_EVTCHN_BIND_VIRQ, &bind);
 	if (rc == -1)