[PATCH 02/13] Drivers: hv: kvp: Cleanup error handling in KVP
From: K. Y. Srinivasan
Date: Thu Jun 21 2012 - 17:19:11 EST
In preparation to implementing IP injection, cleanup the way we propagate
and handle errors both in the driver as well as in the user level daemon.
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
---
drivers/hv/hv_kvp.c | 43 +++++++++++++++++++------------------
include/linux/hyperv.h | 17 +++++++++-----
tools/hv/hv_kvp_daemon.c | 53 +++++++++++++++++++++++----------------------
3 files changed, 60 insertions(+), 53 deletions(-)
diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
index 0012eed..6e6f0c2 100644
--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -50,7 +50,6 @@ static struct {
static void kvp_send_key(struct work_struct *dummy);
-#define TIMEOUT_FIRED 1
static void kvp_respond_to_host(char *key, char *value, int error);
static void kvp_work_func(struct work_struct *dummy);
@@ -97,7 +96,7 @@ kvp_work_func(struct work_struct *dummy)
* If the timer fires, the user-mode component has not responded;
* process the pending transaction.
*/
- kvp_respond_to_host("Unknown key", "Guest timed out", TIMEOUT_FIRED);
+ kvp_respond_to_host("Unknown key", "Guest timed out", HV_E_FAIL);
}
/*
@@ -109,27 +108,31 @@ kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
struct hv_kvp_msg *message;
struct hv_kvp_msg_enumerate *data;
+ int error;
message = (struct hv_kvp_msg *)msg->data;
- switch (message->kvp_hdr.operation) {
- case KVP_OP_REGISTER:
+
+ if (message->kvp_hdr.operation == KVP_OP_REGISTER) {
pr_info("KVP: user-mode registering done.\n");
kvp_register();
kvp_transaction.active = false;
- hv_kvp_onchannelcallback(kvp_transaction.kvp_context);
- break;
-
- default:
- data = &message->body.kvp_enum_data;
- /*
- * Complete the transaction by forwarding the key value
- * to the host. But first, cancel the timeout.
- */
- if (cancel_delayed_work_sync(&kvp_work))
- kvp_respond_to_host(data->data.key,
- data->data.value,
- !strlen(data->data.key));
+ if (kvp_transaction.kvp_context)
+ hv_kvp_onchannelcallback(kvp_transaction.kvp_context);
+ return;
}
+
+ /*
+ * We use the message header information from
+ * the user level daemon to transmit errors.
+ */
+ error = *((int *)(&message->kvp_hdr.operation));
+ data = &message->body.kvp_enum_data;
+ /*
+ * Complete the transaction by forwarding the key value
+ * to the host. But first, cancel the timeout.
+ */
+ if (cancel_delayed_work_sync(&kvp_work))
+ kvp_respond_to_host(data->data.key, data->data.value, error);
}
static void
@@ -287,6 +290,7 @@ kvp_respond_to_host(char *key, char *value, int error)
*/
return;
+ icmsghdrp->status = error;
/*
* If the error parameter is set, terminate the host's enumeration
@@ -294,15 +298,12 @@ kvp_respond_to_host(char *key, char *value, int error)
*/
if (error) {
/*
- * Something failed or the we have timedout;
+ * Something failed or we have timedout;
* terminate the current host-side iteration.
*/
- icmsghdrp->status = HV_S_CONT;
goto response_done;
}
- icmsghdrp->status = HV_S_OK;
-
kvp_msg = (struct hv_kvp_msg *)
&recv_buffer[sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 0497764..9d75699 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -142,6 +142,17 @@ enum hv_kvp_exchg_pool {
KVP_POOL_COUNT /* Number of pools, must be last. */
};
+/*
+ * Some Hyper-V status codes.
+ */
+
+#define HV_S_OK 0x00000000
+#define HV_E_FAIL 0x80004005
+#define HV_S_CONT 0x80070103
+#define HV_ERROR_NOT_SUPPORTED 0x80070032
+#define HV_ERROR_MACHINE_LOCKED 0x800704F7
+#define HV_ERROR_DEVICE_NOT_CONNECTED 0x8007048F
+
#define ADDR_FAMILY_NONE 0x00
#define ADDR_FAMILY_IPV4 0x01
#define ADDR_FAMILY_IPV6 0x02
@@ -1000,12 +1011,6 @@ void vmbus_driver_unregister(struct hv_driver *hv_driver);
#define ICMSGHDRFLAG_REQUEST 2
#define ICMSGHDRFLAG_RESPONSE 4
-#define HV_S_OK 0x00000000
-#define HV_E_FAIL 0x80004005
-#define HV_S_CONT 0x80070103
-#define HV_ERROR_NOT_SUPPORTED 0x80070032
-#define HV_ERROR_MACHINE_LOCKED 0x800704F7
-#define HV_ERROR_DEVICE_NOT_CONNECTED 0x8007048F
/*
* While we want to handle util services as regular devices,
diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index d9834b3..4831997 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -394,7 +394,7 @@ static int kvp_get_value(int pool, __u8 *key, int key_size, __u8 *value,
return 1;
}
-static void kvp_pool_enumerate(int pool, int index, __u8 *key, int key_size,
+static int kvp_pool_enumerate(int pool, int index, __u8 *key, int key_size,
__u8 *value, int value_size)
{
struct kvp_record *record;
@@ -406,16 +406,12 @@ static void kvp_pool_enumerate(int pool, int index, __u8 *key, int key_size,
record = kvp_file_info[pool].records;
if (index >= kvp_file_info[pool].num_records) {
- /*
- * This is an invalid index; terminate enumeration;
- * - a NULL value will do the trick.
- */
- strcpy(value, "");
- return;
+ return 1;
}
memcpy(key, record[index].key, key_size);
memcpy(value, record[index].value, value_size);
+ return 0;
}
@@ -646,6 +642,8 @@ int main(void)
char *p;
char *key_value;
char *key_name;
+ int op;
+ int pool;
daemon(1, 0);
openlog("KVP", 0, LOG_USER);
@@ -721,7 +719,16 @@ int main(void)
incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
hv_msg = (struct hv_kvp_msg *)incoming_cn_msg->data;
- switch (hv_msg->kvp_hdr.operation) {
+ /*
+ * We will use the KVP header information to pass back
+ * the error from this daemon. So, first copy the state
+ * and set the error code to success.
+ */
+ op = hv_msg->kvp_hdr.operation;
+ pool = hv_msg->kvp_hdr.pool;
+ *((int *)(&hv_msg->kvp_hdr.operation)) = HV_S_OK;
+
+ switch (op) {
case KVP_OP_REGISTER:
/*
* Driver is registering with us; stash away the version
@@ -738,20 +745,14 @@ int main(void)
}
continue;
- /*
- * The current protocol with the kernel component uses a
- * NULL key name to pass an error condition.
- * For the SET, GET and DELETE operations,
- * use the existing protocol to pass back error.
- */
-
case KVP_OP_SET:
if (kvp_key_add_or_modify(hv_msg->kvp_hdr.pool,
hv_msg->body.kvp_set.data.key,
hv_msg->body.kvp_set.data.key_size,
hv_msg->body.kvp_set.data.value,
hv_msg->body.kvp_set.data.value_size))
- strcpy(hv_msg->body.kvp_set.data.key, "");
+ *((int *)(&hv_msg->kvp_hdr.operation)) =
+ HV_S_CONT;
break;
case KVP_OP_GET:
@@ -760,14 +761,16 @@ int main(void)
hv_msg->body.kvp_set.data.key_size,
hv_msg->body.kvp_set.data.value,
hv_msg->body.kvp_set.data.value_size))
- strcpy(hv_msg->body.kvp_set.data.key, "");
+ *((int *)(&hv_msg->kvp_hdr.operation)) =
+ HV_S_CONT;
break;
case KVP_OP_DELETE:
if (kvp_key_delete(hv_msg->kvp_hdr.pool,
hv_msg->body.kvp_delete.key,
hv_msg->body.kvp_delete.key_size))
- strcpy(hv_msg->body.kvp_delete.key, "");
+ *((int *)(&hv_msg->kvp_hdr.operation)) =
+ HV_S_CONT;
break;
default:
@@ -782,13 +785,15 @@ int main(void)
* both the key and the value; if not read from the
* appropriate pool.
*/
- if (hv_msg->kvp_hdr.pool != KVP_POOL_AUTO) {
- kvp_pool_enumerate(hv_msg->kvp_hdr.pool,
+ if (pool != KVP_POOL_AUTO) {
+ if (kvp_pool_enumerate(hv_msg->kvp_hdr.pool,
hv_msg->body.kvp_enum_data.index,
hv_msg->body.kvp_enum_data.data.key,
HV_KVP_EXCHANGE_MAX_KEY_SIZE,
hv_msg->body.kvp_enum_data.data.value,
- HV_KVP_EXCHANGE_MAX_VALUE_SIZE);
+ HV_KVP_EXCHANGE_MAX_VALUE_SIZE))
+ *((int *)(&hv_msg->kvp_hdr.operation)) =
+ HV_S_CONT;
goto kvp_done;
}
@@ -841,11 +846,7 @@ int main(void)
strcpy(key_name, "ProcessorArchitecture");
break;
default:
- strcpy(key_value, "Unknown Key");
- /*
- * We use a null key name to terminate enumeration.
- */
- strcpy(key_name, "");
+ *((int *)(&hv_msg->kvp_hdr.operation)) = HV_S_CONT;
break;
}
/*
--
1.7.4.1
--
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