ath10k: rework posting pci rx buffers

It was possible on a host system running low on
memory to end up with no rx buffers on pci pipes.

This makes the driver more robust as it won't fail
to start if it can't allocate all rx buffers right
away. If it is fatal then upper layers will notice
trouble anyway.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 43 insertions, 28 deletions

diff --git a/drivers/net/wireless/ath/ath10k/ce.c b/drivers/net/wireless/ath/ath10k/ce.c
index 8cbc0ab8ad42..f6668162a0a8 100644
--- a/drivers/net/wireless/ath/ath10k/ce.c
+++ b/drivers/net/wireless/ath/ath10k/ce.c
@@ -385,44 +385,59 @@ int ath10k_ce_num_free_src_entries(struct ath10k_ce_pipe *pipe)
 	return delta;
 }
 
-int ath10k_ce_recv_buf_enqueue(struct ath10k_ce_pipe *ce_state,
-			       void *per_recv_context,
-			       u32 buffer)
+
+int __ath10k_ce_rx_num_free_bufs(struct ath10k_ce_pipe *pipe)
 {
-	struct ath10k_ce_ring *dest_ring = ce_state->dest_ring;
-	u32 ctrl_addr = ce_state->ctrl_addr;
-	struct ath10k *ar = ce_state->ar;
+	struct ath10k *ar = pipe->ar;
 	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
+	struct ath10k_ce_ring *dest_ring = pipe->dest_ring;
 	unsigned int nentries_mask = dest_ring->nentries_mask;
-	unsigned int write_index;
-	unsigned int sw_index;
-	int ret;
+	unsigned int write_index = dest_ring->write_index;
+	unsigned int sw_index = dest_ring->sw_index;
 
-	spin_lock_bh(&ar_pci->ce_lock);
-	write_index = dest_ring->write_index;
-	sw_index = dest_ring->sw_index;
+	lockdep_assert_held(&ar_pci->ce_lock);
 
-	if (CE_RING_DELTA(nentries_mask, write_index, sw_index - 1) > 0) {
-		struct ce_desc *base = dest_ring->base_addr_owner_space;
-		struct ce_desc *desc = CE_DEST_RING_TO_DESC(base, write_index);
+	return CE_RING_DELTA(nentries_mask, write_index, sw_index - 1);
+}
+
+int __ath10k_ce_rx_post_buf(struct ath10k_ce_pipe *pipe, void *ctx, u32 paddr)
+{
+	struct ath10k *ar = pipe->ar;
+	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
+	struct ath10k_ce_ring *dest_ring = pipe->dest_ring;
+	unsigned int nentries_mask = dest_ring->nentries_mask;
+	unsigned int write_index = dest_ring->write_index;
+	unsigned int sw_index = dest_ring->sw_index;
+	struct ce_desc *base = dest_ring->base_addr_owner_space;
+	struct ce_desc *desc = CE_DEST_RING_TO_DESC(base, write_index);
+	u32 ctrl_addr = pipe->ctrl_addr;
 
-		/* Update destination descriptor */
-		desc->addr    = __cpu_to_le32(buffer);
-		desc->nbytes = 0;
+	lockdep_assert_held(&ar_pci->ce_lock);
 
-		dest_ring->per_transfer_context[write_index] =
-							per_recv_context;
+	if (CE_RING_DELTA(nentries_mask, write_index, sw_index - 1) == 0)
+		return -EIO;
 
-		/* Update Destination Ring Write Index */
-		write_index = CE_RING_IDX_INCR(nentries_mask, write_index);
-		ath10k_ce_dest_ring_write_index_set(ar, ctrl_addr, write_index);
-		dest_ring->write_index = write_index;
-		ret = 0;
-	} else {
-		ret = -EIO;
-	}
+	desc->addr = __cpu_to_le32(paddr);
+	desc->nbytes = 0;
+
+	dest_ring->per_transfer_context[write_index] = ctx;
+	write_index = CE_RING_IDX_INCR(nentries_mask, write_index);
+	ath10k_ce_dest_ring_write_index_set(ar, ctrl_addr, write_index);
+	dest_ring->write_index = write_index;
 
+	return 0;
+}
+
+int ath10k_ce_rx_post_buf(struct ath10k_ce_pipe *pipe, void *ctx, u32 paddr)
+{
+	struct ath10k *ar = pipe->ar;
+	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
+	int ret;
+
+	spin_lock_bh(&ar_pci->ce_lock);
+	ret = __ath10k_ce_rx_post_buf(pipe, ctx, paddr);
 	spin_unlock_bh(&ar_pci->ce_lock);
+
 	return ret;
 }