From: Andrea Parri (Microsoft) Date: Tue, 19 Apr 2022 12:23:22 +0000 (+0200) Subject: Drivers: hv: vmbus: Introduce vmbus_sendpacket_getid() X-Git-Tag: v5.19-rc1~106^2~23 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b03afa57c65e1e045e02df49777e953742745f4c;p=thirdparty%2Flinux.git 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 Signed-off-by: Andrea Parri (Microsoft) Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20220419122325.10078-4-parri.andrea@gmail.com Signed-off-by: Wei Liu --- diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 20fc8d50a0398..585a8084848bf 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -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); diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index 6b45c22bb717e..4f5b824b16cf4 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -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, diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 3d215d9dec433..e101b11f95e5d 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -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); diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 2d085d951ee45..7cb8718825eeb 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -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,