/* When large numbers of devices are present on the host, it's
* possible for udev not to realize that it has work to do before we
* get here. We thus keep trying to find the new device we just
* created for up to LINUX_NEW_DEVICE_WAIT_TIME. Note that udev's
* default settle time is 180 seconds, so once udev realizes that it
* has work to do, it might take that long for the udev wait to
* return. Thus the total maximum time for this function to return is
* the udev settle time plus LINUX_NEW_DEVICE_WAIT_TIME.
*
* This whole area is a race, but if we retry the udev wait for
* LINUX_NEW_DEVICE_WAIT_TIME seconds and there's still no device,
* it's probably safe to assume it's not going to appear.
*/
static virNodeDevicePtr
find_new_device(virConnectPtr conn, const char *wwnn, const char *wwpn)
{
virNodeDevicePtr dev = NULL;
time_t start = 0, now = 0;
/* The thread that creates the device takes the driver lock, so we
* must release it in order to allow the device to be created.
* We're not doing anything with the driver pointer at this point,
* so it's safe to release it, assuming that the pointer itself
* doesn't become invalid. */
nodeDeviceUnlock();
get_time(&start);
while ((now - start) < LINUX_NEW_DEVICE_WAIT_TIME) {
virFileWaitForDevices();
dev = nodeDeviceLookupSCSIHostByWWN(conn, wwnn, wwpn, 0);
if (dev != NULL)
break;
sleep(5);
if (get_time(&now) == -1)
break;
}
nodeDeviceLock();
return dev;
}
static int
virStorageBackendMpathRefreshPool(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool)
{
int retval = 0;
VIR_DEBUG("conn=%p, pool=%p", conn, pool);
pool->def->allocation = pool->def->capacity = pool->def->available = 0;
virFileWaitForDevices();
virStorageBackendGetMaps(pool);
return retval;
}
static int
virStorageBackendISCSIGetHostNumber(const char *sysfs_path,
uint32_t *host)
{
int retval = 0;
DIR *sysdir = NULL;
struct dirent *dirent = NULL;
int direrr;
VIR_DEBUG("Finding host number from '%s'", sysfs_path);
virFileWaitForDevices();
sysdir = opendir(sysfs_path);
if (sysdir == NULL) {
virReportSystemError(errno,
_("Failed to opendir path '%s'"), sysfs_path);
retval = -1;
goto out;
}
while ((direrr = virDirRead(sysdir, &dirent, sysfs_path)) > 0) {
if (STREQLEN(dirent->d_name, "target", strlen("target"))) {
if (sscanf(dirent->d_name,
"target%u:", host) != 1) {
VIR_DEBUG("Failed to parse target '%s'", dirent->d_name);
retval = -1;
break;
}
}
}
if (direrr < 0)
retval = -1;
closedir(sysdir);
out:
return retval;
}
