Drivers: hv: vmbus: Introduce vmbus_sendpacket_getid()

The function can be used to send a VMbus packet and retrieve the
corresponding transaction ID.  It will be used by hv_pci.

No functional change.

Suggested-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20220419122325.10078-4-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
This commit is contained in:
Andrea Parri (Microsoft) 2022-04-19 14:23:22 +02:00 committed by Wei Liu
parent de5ddb7d44
commit b03afa57c6
4 changed files with 51 additions and 10 deletions

View file

@ -1022,11 +1022,13 @@ void vmbus_close(struct vmbus_channel *channel)
EXPORT_SYMBOL_GPL(vmbus_close);
/**
* vmbus_sendpacket() - Send the specified buffer on the given channel
* vmbus_sendpacket_getid() - Send the specified buffer on the given channel
* @channel: Pointer to vmbus_channel structure
* @buffer: Pointer to the buffer you want to send the data from.
* @bufferlen: Maximum size of what the buffer holds.
* @requestid: Identifier of the request
* @trans_id: Identifier of the transaction associated to this request, if
* the send is successful; undefined, otherwise.
* @type: Type of packet that is being sent e.g. negotiate, time
* packet etc.
* @flags: 0 or VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
@ -1036,8 +1038,8 @@ EXPORT_SYMBOL_GPL(vmbus_close);
*
* Mainly used by Hyper-V drivers.
*/
int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
u32 bufferlen, u64 requestid,
int vmbus_sendpacket_getid(struct vmbus_channel *channel, void *buffer,
u32 bufferlen, u64 requestid, u64 *trans_id,
enum vmbus_packet_type type, u32 flags)
{
struct vmpacket_descriptor desc;
@ -1063,7 +1065,31 @@ int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
bufferlist[2].iov_base = &aligned_data;
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
return hv_ringbuffer_write(channel, bufferlist, num_vecs, requestid);
return hv_ringbuffer_write(channel, bufferlist, num_vecs, requestid, trans_id);
}
EXPORT_SYMBOL(vmbus_sendpacket_getid);
/**
* vmbus_sendpacket() - Send the specified buffer on the given channel
* @channel: Pointer to vmbus_channel structure
* @buffer: Pointer to the buffer you want to send the data from.
* @bufferlen: Maximum size of what the buffer holds.
* @requestid: Identifier of the request
* @type: Type of packet that is being sent e.g. negotiate, time
* packet etc.
* @flags: 0 or VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
*
* Sends data in @buffer directly to Hyper-V via the vmbus.
* This will send the data unparsed to Hyper-V.
*
* Mainly used by Hyper-V drivers.
*/
int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
u32 bufferlen, u64 requestid,
enum vmbus_packet_type type, u32 flags)
{
return vmbus_sendpacket_getid(channel, buffer, bufferlen,
requestid, NULL, type, flags);
}
EXPORT_SYMBOL(vmbus_sendpacket);
@ -1122,7 +1148,7 @@ int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
bufferlist[2].iov_base = &aligned_data;
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
return hv_ringbuffer_write(channel, bufferlist, 3, requestid);
return hv_ringbuffer_write(channel, bufferlist, 3, requestid, NULL);
}
EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
@ -1160,7 +1186,7 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
bufferlist[2].iov_base = &aligned_data;
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
return hv_ringbuffer_write(channel, bufferlist, 3, requestid);
return hv_ringbuffer_write(channel, bufferlist, 3, requestid, NULL);
}
EXPORT_SYMBOL_GPL(vmbus_sendpacket_mpb_desc);

View file

@ -181,7 +181,7 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
int hv_ringbuffer_write(struct vmbus_channel *channel,
const struct kvec *kv_list, u32 kv_count,
u64 requestid);
u64 requestid, u64 *trans_id);
int hv_ringbuffer_read(struct vmbus_channel *channel,
void *buffer, u32 buflen, u32 *buffer_actual_len,

View file

@ -283,7 +283,7 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
/* Write to the ring buffer. */
int hv_ringbuffer_write(struct vmbus_channel *channel,
const struct kvec *kv_list, u32 kv_count,
u64 requestid)
u64 requestid, u64 *trans_id)
{
int i;
u32 bytes_avail_towrite;
@ -294,7 +294,7 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
unsigned long flags;
struct hv_ring_buffer_info *outring_info = &channel->outbound;
struct vmpacket_descriptor *desc = kv_list[0].iov_base;
u64 rqst_id = VMBUS_NO_RQSTOR;
u64 __trans_id, rqst_id = VMBUS_NO_RQSTOR;
if (channel->rescind)
return -ENODEV;
@ -353,7 +353,15 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
}
}
desc = hv_get_ring_buffer(outring_info) + old_write;
desc->trans_id = (rqst_id == VMBUS_NO_RQSTOR) ? requestid : rqst_id;
__trans_id = (rqst_id == VMBUS_NO_RQSTOR) ? requestid : rqst_id;
/*
* Ensure the compiler doesn't generate code that reads the value of
* the transaction ID from the ring buffer, which is shared with the
* Hyper-V host and subject to being changed at any time.
*/
WRITE_ONCE(desc->trans_id, __trans_id);
if (trans_id)
*trans_id = __trans_id;
/* Set previous packet start */
prev_indices = hv_get_ring_bufferindices(outring_info);

View file

@ -1161,6 +1161,13 @@ extern int vmbus_open(struct vmbus_channel *channel,
extern void vmbus_close(struct vmbus_channel *channel);
extern int vmbus_sendpacket_getid(struct vmbus_channel *channel,
void *buffer,
u32 bufferLen,
u64 requestid,
u64 *trans_id,
enum vmbus_packet_type type,
u32 flags);
extern int vmbus_sendpacket(struct vmbus_channel *channel,
void *buffer,
u32 bufferLen,