static int get_be_domid(const char *str)
{
int len1, len2;
const char *ptr;
char *tptr, num[10];
len2 = strsep_len(str, '/', 3);
if ( len2 < 0 ) return -1;
len1 = strsep_len(str, '/', 2);
ptr = str + len1 + 1;
strncpy(num, ptr, len2 - len1 - 1);
tptr = num + (len2 - len1 - 1);
*tptr = '\0';
return atoi(num);
}
static int get_be_id(const char *str)
{
int len,end;
const char *ptr;
char *tptr, num[10];
len = strsep_len(str, '/', 6);
end = strlen(str);
if( (len < 0) || (end < 0) ) return -1;
ptr = str + len + 1;
strncpy(num, ptr, end - len);
tptr = num + (end - (len + 1));
*tptr = '\0';
return atoi(num);
}
void xenbus_dev_changed(const char *node, struct xen_bus_type *bus)
{
int exists, rootlen;
struct xenbus_device *dev;
char type[XEN_BUS_ID_SIZE];
const char *p, *root;
if (char_count(node, '/') < 2)
return;
exists = xenbus_exists(XBT_NIL, node, "");
if (!exists) {
xenbus_cleanup_devices(node, &bus->bus);
return;
}
/* backend/<type>/... or device/<type>/... */
p = strchr(node, '/') + 1;
snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p);
type[XEN_BUS_ID_SIZE-1] = '\0';
rootlen = strsep_len(node, '/', bus->levels);
if (rootlen < 0)
return;
root = kasprintf(GFP_KERNEL, "%.*s", rootlen, node);
if (!root)
return;
dev = xenbus_device_find(root, &bus->bus);
if (!dev)
xenbus_probe_node(bus, type, root);
else
put_device(&dev->dev);
kfree(root);
}
/**
* Xenstore watch callback entry point. This code replaces the hotplug scripts,
* and as soon as the xenstore backend driver entries are created, this script
* gets called.
*/
static void ueblktap_probe(struct xs_handle *h, struct xenbus_watch *w,
const char *bepath_im)
{
struct backend_info *be = NULL;
char *frontend = NULL, *bepath = NULL, *p;
int er, len;
blkif_t *blkif;
bepath = strdup(bepath_im);
if (!bepath) {
DPRINTF("No path\n");
return;
}
/*
*asserts that xenstore structure is always 7 levels deep
*e.g. /local/domain/0/backend/vbd/1/2049
*/
len = strsep_len(bepath, '/', 7);
if (len < 0)
goto free_be;
if (bepath[len] != '\0')
goto free_be;
be = malloc(sizeof(*be));
if (!be) {
DPRINTF("ERROR: allocating backend structure\n");
goto free_be;
}
memset(be, 0, sizeof(*be));
frontend = NULL;
er = xs_gather(h, bepath,
"frontend-id", "%li", &be->frontend_id,
"frontend", NULL, &frontend,
NULL);
if (er) {
/*
*Unable to find frontend entries,
*bus-id is no longer valid
*/
DPRINTF("ERROR: Frontend-id check failed, removing backend: "
"[%s]\n",bepath);
/**
* BE info should already exist,
* free new mem and find old entry
*/
free(be);
be = be_lookup_be(bepath);
if ( (be != NULL) && (be->blkif != NULL) )
backend_remove(h, be);
else goto free_be;
if (bepath)
free(bepath);
return;
}
/* Are we already tracking this device? */
if (be_exists_be(bepath))
goto free_be;
be->backpath = bepath;
be->frontpath = frontend;
list_add(&be->list, &belist);
DPRINTF("[PROBE]\tADDED NEW DEVICE (%s)\n", bepath);
DPRINTF("\tFRONTEND (%s),(%ld)\n", frontend,be->frontend_id);
ueblktap_setup(h, bepath);
return;
free_be:
if (frontend)
free(frontend);
if (bepath)
free(bepath);
if (be)
free(be);
}
