[PATCH 3/4] drivers: hv: kvp: Cleanup the kernel/user protocol

K. Y. Srinivasan
2012-02-03T00:56:50Z

Now, cleanup the user/kernel KVP protocol by using the same structure
definition that is used for host/guest KVP protocol. This simplifies the code.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/hv/hv_kvp.c | 41 +++++++++++++++++++++++++----------------
include/linux/hyperv.h | 30 +++++-------------------------
tools/hv/hv_kvp_daemon.c | 30 +++++++++++++++---------------
3 files changed, 45 insertions(+), 56 deletions(-)

diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
index 4a6971e..0ef4c1f 100644
--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -71,15 +71,20 @@ kvp_register(void)
{

struct cn_msg *msg;
+ struct hv_kvp_msg *kvp_msg;
+ char *version;

- msg = kzalloc(sizeof(*msg) + strlen(HV_DRV_VERSION) + 1 , GFP_ATOMIC);
+ msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg), GFP_ATOMIC);

if (msg) {
+ kvp_msg = (struct hv_kvp_msg *)msg->data;
+ version = kvp_msg->body.kvp_version;
msg->id.idx = CN_KVP_IDX;
msg->id.val = CN_KVP_VAL;
- msg->seq = KVP_REGISTER;
- strcpy(msg->data, HV_DRV_VERSION);
- msg->len = strlen(HV_DRV_VERSION) + 1;
+
+ kvp_msg->kvp_hdr.operation = KVP_OP_REGISTER;
+ strcpy(version, HV_DRV_VERSION);
+ msg->len = sizeof(struct hv_kvp_msg);
cn_netlink_send(msg, 0, GFP_ATOMIC);
kfree(msg);
}
@@ -101,23 +106,24 @@ kvp_work_func(struct work_struct *dummy)
static void
kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
- struct hv_ku_msg *message;
+ struct hv_kvp_msg *message;
+ struct hv_kvp_msg_enumerate *data;

- message = (struct hv_ku_msg *)msg->data;
- if (msg->seq == KVP_REGISTER) {
+ message = (struct hv_kvp_msg *)msg->data;
+ if (message->kvp_hdr.operation == KVP_OP_REGISTER) {
pr_info("KVP: user-mode registering done.\n");
kvp_register();
}

- if (msg->seq == KVP_USER_SET) {
+ if (message->kvp_hdr.operation == KVP_OP_ENUMERATE) {
+ 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(message->kvp_key,
- message->kvp_value,
- !strlen(message->kvp_key));
+ kvp_respond_to_host(data->data.key, data->data.value,
+ !strlen(data->data.key));
}
}

@@ -125,6 +131,7 @@ static void
kvp_send_key(struct work_struct *dummy)
{
struct cn_msg *msg;
+ struct hv_kvp_msg *message;
int index = kvp_transaction.index;

msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg) , GFP_ATOMIC);
@@ -132,9 +139,11 @@ kvp_send_key(struct work_struct *dummy)
if (msg) {
msg->id.idx = CN_KVP_IDX;
msg->id.val = CN_KVP_VAL;
- msg->seq = KVP_KERNEL_GET;
- ((struct hv_ku_msg *)msg->data)->kvp_index = index;
- msg->len = sizeof(struct hv_ku_msg);
+
+ message = (struct hv_kvp_msg *)msg->data;
+ message->kvp_hdr.operation = KVP_OP_ENUMERATE;
+ message->body.kvp_enum_data.index = index;
+ msg->len = sizeof(struct hv_kvp_msg);
cn_netlink_send(msg, 0, GFP_ATOMIC);
kfree(msg);
}
@@ -191,7 +200,7 @@ kvp_respond_to_host(char *key, char *value, int error)
kvp_msg = (struct hv_kvp_msg *)
&recv_buffer[sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
- kvp_data = &kvp_msg->kvp_data;
+ kvp_data = &kvp_msg->body.kvp_enum_data;
key_name = key;

/*
@@ -266,7 +275,7 @@ void hv_kvp_onchannelcallback(void *context)
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];

- kvp_data = &kvp_msg->kvp_data;
+ kvp_data = &kvp_msg->body.kvp_enum_data;

/*
* We only support the "get" operation on
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index b822978..75aee67 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -113,30 +113,6 @@
* (not supported), a NULL key string is returned.
*/

-/*
- *
- * The following definitions are shared with the user-mode component; do not
- * change any of this without making the corresponding changes in
- * the KVP user-mode component.
- */
-
-enum hv_ku_op {
- KVP_REGISTER = 0, /* Register the user mode component */
- KVP_KERNEL_GET, /* Kernel is requesting the value */
- KVP_KERNEL_SET, /* Kernel is providing the value */
- KVP_USER_GET, /* User is requesting the value */
- KVP_USER_SET /* User is providing the value */
-};
-
-struct hv_ku_msg {
- __u32 kvp_index; /* Key index */
- __u8 kvp_key[HV_KVP_EXCHANGE_MAX_KEY_SIZE]; /* Key name */
- __u8 kvp_value[HV_KVP_EXCHANGE_MAX_VALUE_SIZE]; /* Key value */
-};
-
-
-
-

/*
* Registry value types.
@@ -149,6 +125,7 @@ enum hv_kvp_exchg_op {
KVP_OP_SET,
KVP_OP_DELETE,
KVP_OP_ENUMERATE,
+ KVP_OP_REGISTER,
KVP_OP_COUNT /* Number of operations, must be last. */
};

@@ -182,7 +159,10 @@ struct hv_kvp_msg_enumerate {

struct hv_kvp_msg {
struct hv_kvp_hdr kvp_hdr;
- struct hv_kvp_msg_enumerate kvp_data;
+ union {
+ struct hv_kvp_msg_enumerate kvp_enum_data;
+ char kvp_version[HV_KVP_EXCHANGE_MAX_KEY_SIZE];
+ } body;
} __attribute__((packed));

#ifdef __KERNEL__
diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index b75523c..4ebf703 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -302,7 +302,7 @@ int main(void)
struct pollfd pfd;
struct nlmsghdr *incoming_msg;
struct cn_msg *incoming_cn_msg;
- struct hv_ku_msg *hv_msg;
+ struct hv_kvp_msg *hv_msg;
char *p;
char *key_value;
char *key_name;
@@ -340,9 +340,11 @@ int main(void)
message = (struct cn_msg *)kvp_send_buffer;
message->id.idx = CN_KVP_IDX;
message->id.val = CN_KVP_VAL;
- message->seq = KVP_REGISTER;
+
+ hv_msg = (struct hv_kvp_msg *)message->data;
+ hv_msg->kvp_hdr.operation = KVP_OP_REGISTER;
message->ack = 0;
- message->len = 0;
+ message->len = sizeof(struct hv_kvp_msg);

len = netlink_send(fd, message);
if (len < 0) {
@@ -368,14 +370,15 @@ int main(void)

incoming_msg = (struct nlmsghdr *)kvp_recv_buffer;
incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
+ hv_msg = (struct hv_kvp_msg *)incoming_cn_msg->data;

- switch (incoming_cn_msg->seq) {
- case KVP_REGISTER:
+ switch (hv_msg->kvp_hdr.operation) {
+ case KVP_OP_REGISTER:
/*
* Driver is registering with us; stash away the version
* information.
*/
- p = (char *)incoming_cn_msg->data;
+ p = (char *)hv_msg->body.kvp_version;
lic_version = malloc(strlen(p) + 1);
if (lic_version) {
strcpy(lic_version, p);
@@ -386,17 +389,15 @@ int main(void)
}
continue;

- case KVP_KERNEL_GET:
- break;
default:
- continue;
+ break;
}

- hv_msg = (struct hv_ku_msg *)incoming_cn_msg->data;
- key_name = (char *)hv_msg->kvp_key;
- key_value = (char *)hv_msg->kvp_value;
+ hv_msg = (struct hv_kvp_msg *)incoming_cn_msg->data;
+ key_name = (char *)hv_msg->body.kvp_enum_data.data.key;
+ key_value = (char *)hv_msg->body.kvp_enum_data.data.value;

- switch (hv_msg->kvp_index) {
+ switch (hv_msg->body.kvp_enum_data.index) {
case FullyQualifiedDomainName:
kvp_get_domain_name(key_value,
HV_KVP_EXCHANGE_MAX_VALUE_SIZE);
@@ -456,9 +457,8 @@ int main(void)

incoming_cn_msg->id.idx = CN_KVP_IDX;
incoming_cn_msg->id.val = CN_KVP_VAL;
- incoming_cn_msg->seq = KVP_USER_SET;
incoming_cn_msg->ack = 0;
- incoming_cn_msg->len = sizeof(struct hv_ku_msg);
+ incoming_cn_msg->len = sizeof(struct hv_kvp_msg);

len = netlink_send(fd, incoming_cn_msg);
if (len < 0) {
--
1.7.4.1