@@ -70,6 +70,7 @@ typedef struct IscsiLun {
bool dpofua;
bool has_write_same;
bool force_next_flush;
+ bool request_timed_out;
} IscsiLun;
typedef struct IscsiTask {
@@ -100,7 +101,8 @@ typedef struct IscsiAIOCB {
#endif
} IscsiAIOCB;
-#define EVENT_INTERVAL 250
+/* libiscsi uses time_t so its enough to process events every second */
+#define EVENT_INTERVAL 1000
#define NOP_INTERVAL 5000
#define MAX_NOP_FAILURES 3
#define ISCSI_CMD_RETRIES ARRAY_SIZE(iscsi_retry_times)
@@ -187,13 +189,18 @@ iscsi_co_generic_cb(struct iscsi_context *iscsi, int status,
iTask->do_retry = 1;
goto out;
}
- /* status 0x28 is SCSI_TASK_SET_FULL. It was first introduced
- * in libiscsi 1.10.0. Hardcode this value here to avoid
- * the need to bump the libiscsi requirement to 1.10.0 */
- if (status == SCSI_STATUS_BUSY || status == 0x28) {
+ if (status == SCSI_STATUS_BUSY || status == SCSI_STATUS_TIMEOUT ||
+ status == SCSI_STATUS_TASK_SET_FULL) {
unsigned retry_time =
exp_random(iscsi_retry_times[iTask->retries - 1]);
- error_report("iSCSI Busy/TaskSetFull (retry #%u in %u ms): %s",
+ if (status == SCSI_STATUS_TIMEOUT) {
+ /* make sure the request is rescheduled AFTER the
+ * reconnect is initiated */
+ retry_time = EVENT_INTERVAL * 2;
+ iTask->iscsilun->request_timed_out = true;
+ }
+ error_report("iSCSI Busy/TaskSetFull/TimeOut"
+ " (retry #%u in %u ms): %s",
iTask->retries, retry_time,
iscsi_get_error(iscsi));
aio_timer_init(iTask->iscsilun->aio_context,
@@ -277,20 +284,26 @@ iscsi_set_events(IscsiLun *iscsilun)
iscsilun);
iscsilun->events = ev;
}
-
- /* newer versions of libiscsi may return zero events. In this
- * case start a timer to ensure we are able to return to service
- * once this situation changes. */
- if (!ev) {
- timer_mod(iscsilun->event_timer,
- qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
- }
}
-static void iscsi_timed_set_events(void *opaque)
+static void iscsi_timed_check_events(void *opaque)
{
IscsiLun *iscsilun = opaque;
+
+ /* check for timed out requests */
+ iscsi_service(iscsilun->iscsi, 0);
+
+ if (iscsilun->request_timed_out) {
+ iscsilun->request_timed_out = false;
+ iscsi_reconnect(iscsilun->iscsi);
+ }
+
+ /* newer versions of libiscsi may return zero events. Ensure we are able
+ * to return to service once this situation changes. */
iscsi_set_events(iscsilun);
+
+ timer_mod(iscsilun->event_timer,
+ qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
}
static void
@@ -1093,16 +1106,37 @@ static char *parse_initiator_name(const char *target)
return iscsi_name;
}
+static int parse_timeout(const char *target)
+{
+ QemuOptsList *list;
+ QemuOpts *opts;
+ const char *timeout;
+
+ list = qemu_find_opts("iscsi");
+ if (list) {
+ opts = qemu_opts_find(list, target);
+ if (!opts) {
+ opts = QTAILQ_FIRST(&list->head);
+ }
+ if (opts) {
+ timeout = qemu_opt_get(opts, "timeout");
+ if (timeout) {
+ return atoi(timeout);
+ }
+ }
+ }
+
+ return 0;
+}
+
static void iscsi_nop_timed_event(void *opaque)
{
IscsiLun *iscsilun = opaque;
- if (iscsi_get_nops_in_flight(iscsilun->iscsi) > MAX_NOP_FAILURES) {
+ if (iscsi_get_nops_in_flight(iscsilun->iscsi) >= MAX_NOP_FAILURES) {
error_report("iSCSI: NOP timeout. Reconnecting...");
- iscsi_reconnect(iscsilun->iscsi);
- }
-
- if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
+ iscsilun->request_timed_out = true;
+ } else if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
error_report("iSCSI: failed to sent NOP-Out. Disabling NOP messages.");
return;
}
@@ -1260,10 +1294,13 @@ static void iscsi_attach_aio_context(BlockDriverState *bs,
timer_mod(iscsilun->nop_timer,
qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
- /* Prepare a timer for a delayed call to iscsi_set_events */
+ /* Set up a timer for periodic calls to iscsi_set_events and to
+ * scan for command timeout */
iscsilun->event_timer = aio_timer_new(iscsilun->aio_context,
QEMU_CLOCK_REALTIME, SCALE_MS,
- iscsi_timed_set_events, iscsilun);
+ iscsi_timed_check_events, iscsilun);
+ timer_mod(iscsilun->event_timer,
+ qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
}
static void iscsi_modesense_sync(IscsiLun *iscsilun)
@@ -1388,6 +1425,8 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags,
goto out;
}
+ iscsi_set_timeout(iscsi, parse_timeout(iscsi_url->target));
+
if (iscsi_full_connect_sync(iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
error_setg(errp, "iSCSI: Failed to connect to LUN : %s",
iscsi_get_error(iscsi));
@@ -1736,6 +1775,10 @@ static QemuOptsList qemu_iscsi_opts = {
.name = "initiator-name",
.type = QEMU_OPT_STRING,
.help = "Initiator iqn name to use when connecting",
+ },{
+ .name = "timeout",
+ .type = QEMU_OPT_NUMBER,
+ .help = "Request timeout in seconds (default 0 = no timeout)",
},
{ /* end of list */ }
},
@@ -3618,15 +3618,15 @@ if compile_prog "" "" ; then
fi
##########################################
-# Do we have libiscsi >= 1.9.0
+# Do we have libiscsi >= 1.10.0
if test "$libiscsi" != "no" ; then
- if $pkg_config --atleast-version=1.9.0 libiscsi; then
+ if $pkg_config --atleast-version=1.10.0 libiscsi; then
libiscsi="yes"
libiscsi_cflags=$($pkg_config --cflags libiscsi)
libiscsi_libs=$($pkg_config --libs libiscsi)
else
if test "$libiscsi" = "yes" ; then
- feature_not_found "libiscsi" "Install libiscsi >= 1.9.0"
+ feature_not_found "libiscsi" "Install libiscsi >= 1.10.0"
fi
libiscsi="no"
fi
@@ -2294,6 +2294,9 @@ By default qemu will use the iSCSI initiator-name
'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
line or a configuration file.
+Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
+stalled requests and force a reestablishment of the session. The timeout
+is specified in seconds. The default is 0 which means no timeout.
Example (without authentication):
@example
@@ -2321,6 +2324,7 @@ DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
"-iscsi [user=user][,password=password]\n"
" [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
" [,initiator-name=initiator-iqn][,id=target-iqn]\n"
+ " [,timeout=timeout]\n"
" iSCSI session parameters\n", QEMU_ARCH_ALL)
STEXI