[PATCH v1 1/5] RDMA/efa: mark mmio_read seq_num as guarded by mmio_read lock

[Timothy Day <timday@thelustrecollective.com>]

seq_num is only ever accessed while holding the mmio_read lock,
so annotate it with __guarded_by() for Clang's context analysis.

The mmio_read lock initialisation in efa_com_mmio_reg_read_init()
is marked with guard(spinlock_init). This covers the mmio_read
seq_num initialisation (later in the function) that is done
before concurrent access is possible.

Signed-off-by: Timothy Day <timday@thelustrecollective.com>
---
 drivers/infiniband/hw/efa/efa_com.c | 2 +-
 drivers/infiniband/hw/efa/efa_com.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/efa/efa_com.c b/drivers/infiniband/hw/efa/efa_com.c
index 7097d1c2f23df..c48971595d5ef 100644
--- a/drivers/infiniband/hw/efa/efa_com.c
+++ b/drivers/infiniband/hw/efa/efa_com.c
@@ -956,7 +956,7 @@ int efa_com_mmio_reg_read_init(struct efa_com_dev *edev)
 {
 	struct efa_com_mmio_read *mmio_read = &edev->mmio_read;
 
-	spin_lock_init(&mmio_read->lock);
+	guard(spinlock_init)(&mmio_read->lock);
 	mmio_read->read_resp =
 		dma_alloc_coherent(edev->dmadev, sizeof(*mmio_read->read_resp),
 				   &mmio_read->read_resp_dma_addr, GFP_KERNEL);
diff --git a/drivers/infiniband/hw/efa/efa_com.h b/drivers/infiniband/hw/efa/efa_com.h
index 599db9d583bf5..cd1c68cdc5c43 100644
--- a/drivers/infiniband/hw/efa/efa_com.h
+++ b/drivers/infiniband/hw/efa/efa_com.h
@@ -99,7 +99,7 @@ struct efa_com_aenq {
 struct efa_com_mmio_read {
 	struct efa_admin_mmio_req_read_less_resp *read_resp;
 	dma_addr_t read_resp_dma_addr;
-	u16 seq_num;
+	u16 seq_num __guarded_by(&lock);
 	u16 mmio_read_timeout; /* usecs */
 	/* serializes mmio reads */
 	spinlock_t lock;
-- 
2.39.5