Commit b91eaf72 authored by Andrea Parri (Microsoft)'s avatar Andrea Parri (Microsoft) Committed by Wei Liu
Browse files

Drivers: hv: vmbus: Introduce {lock,unlock}_requestor() 



To abtract the lock and unlock operations on the requestor spin lock.
The helpers will come in handy in hv_pci.

No functional change.

Suggested-by: default avatarMichael Kelley <mikelley@microsoft.com>
Signed-off-by: default avatarAndrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: default avatarMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20220419122325.10078-6-parri.andrea@gmail.com


Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
parent 0aadb6a7

drivers/hv/channel.c

+5 −6
Original line number Diff line number Diff line
@@ -1252,12 +1252,12 @@ u64 vmbus_next_request_id(struct vmbus_channel *channel, u64 rqst_addr) 
	if (!channel->rqstor_size)

		return VMBUS_NO_RQSTOR;



	spin_lock_irqsave(&rqstor->req_lock, flags);

	lock_requestor(channel, flags);

	current_id = rqstor->next_request_id;



	/* Requestor array is full */

	if (current_id >= rqstor->size) {

		spin_unlock_irqrestore(&rqstor->req_lock, flags);

		unlock_requestor(channel, flags);

		return VMBUS_RQST_ERROR;

	}
@@ -1267,7 +1267,7 @@ u64 vmbus_next_request_id(struct vmbus_channel *channel, u64 rqst_addr) 
	/* The already held spin lock provides atomicity */

	bitmap_set(rqstor->req_bitmap, current_id, 1);



	spin_unlock_irqrestore(&rqstor->req_lock, flags);

	unlock_requestor(channel, flags);



	/*

	 * Cannot return an ID of 0, which is reserved for an unsolicited
@@ -1327,13 +1327,12 @@ EXPORT_SYMBOL_GPL(__vmbus_request_addr_match); 
u64 vmbus_request_addr_match(struct vmbus_channel *channel, u64 trans_id,

			     u64 rqst_addr)

{

	struct vmbus_requestor *rqstor = &channel->requestor;

	unsigned long flags;

	u64 req_addr;



	spin_lock_irqsave(&rqstor->req_lock, flags);

	lock_requestor(channel, flags);

	req_addr = __vmbus_request_addr_match(channel, trans_id, rqst_addr);

	spin_unlock_irqrestore(&rqstor->req_lock, flags);

	unlock_requestor(channel, flags);



	return req_addr;

}

include/linux/hyperv.h

+15 −0
Original line number Diff line number Diff line
@@ -1042,6 +1042,21 @@ struct vmbus_channel { 
	u32 max_pkt_size;

};



#define lock_requestor(channel, flags)					\

do {									\

	struct vmbus_requestor *rqstor = &(channel)->requestor;		\

									\

	spin_lock_irqsave(&rqstor->req_lock, flags);			\

} while (0)



static __always_inline void unlock_requestor(struct vmbus_channel *channel,

					     unsigned long flags)

{

	struct vmbus_requestor *rqstor = &channel->requestor;



	spin_unlock_irqrestore(&rqstor->req_lock, flags);

}



u64 vmbus_next_request_id(struct vmbus_channel *channel, u64 rqst_addr);

u64 __vmbus_request_addr_match(struct vmbus_channel *channel, u64 trans_id,

			       u64 rqst_addr);