[PATCH v2 066/127] smb: client: make use of smbdirect_connection_{alloc, free}_send_io()

[Stefan Metzmacher]

This simplifies the code and allows us to share more code in common
with the server.

The only difference is that we use ib_dma_unmap_page() for all sges,
this simplifies the logic and doesn't matter as
ib_dma_unmap_single() and ib_dma_unmap_page() both operate
on dma_addr_t and dma_unmap_single_attrs() is just an
alias for dma_unmap_page_attrs().

We already had such an inconsistency before
as we called ib_dma_unmap_single(), while we mapped
using ib_dma_map_page() in smb_set_sge().

Cc: Steve French <smfrench at gmail.com>
Cc: Tom Talpey <tom at talpey.com>
Cc: Long Li <longli at microsoft.com>
Cc: Namjae Jeon <linkinjeon at kernel.org>
Cc: linux-cifs at vger.kernel.org
Cc: samba-technical at lists.samba.org
Signed-off-by: Stefan Metzmacher <metze at samba.org>
Signed-off-by: Steve French <stfrench at microsoft.com>
---
 fs/smb/client/smbdirect.c | 42 ++++++++++++---------------------------
 1 file changed, 13 insertions(+), 29 deletions(-)

diff --git a/fs/smb/client/smbdirect.c b/fs/smb/client/smbdirect.c
index ab8ce4c46bd6..1eed0686a34d 100644
--- a/fs/smb/client/smbdirect.c
+++ b/fs/smb/client/smbdirect.c
@@ -390,7 +390,6 @@ static inline void *smbdirect_recv_io_payload(struct smbdirect_recv_io *response
 /* Called when a RDMA send is done */
 static void send_done(struct ib_cq *cq, struct ib_wc *wc)
 {
-	int i;
 	struct smbdirect_send_io *request =
 		container_of(wc->wr_cqe, struct smbdirect_send_io, cqe);
 	struct smbdirect_socket *sc = request->socket;
@@ -399,12 +398,8 @@ static void send_done(struct ib_cq *cq, struct ib_wc *wc)
 	log_rdma_send(INFO, "smbdirect_send_io 0x%p completed wc->status=%s\n",
 		request, ib_wc_status_msg(wc->status));
 
-	for (i = 0; i < request->num_sge; i++)
-		ib_dma_unmap_single(sc->ib.dev,
-			request->sge[i].addr,
-			request->sge[i].length,
-			DMA_TO_DEVICE);
-	mempool_free(request, sc->send_io.mem.pool);
+	/* Note this frees wc->wr_cqe, but not wc */
+	smbdirect_connection_free_send_io(request);
 	lcredits += 1;
 
 	if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_SEND) {
@@ -835,15 +830,13 @@ static int smbd_post_send_negotiate_req(struct smbdirect_socket *sc)
 {
 	struct smbdirect_socket_parameters *sp = &sc->parameters;
 	struct ib_send_wr send_wr;
-	int rc = -ENOMEM;
+	int rc;
 	struct smbdirect_send_io *request;
 	struct smbdirect_negotiate_req *packet;
 
-	request = mempool_alloc(sc->send_io.mem.pool, GFP_KERNEL);
-	if (!request)
-		return rc;
-
-	request->socket = sc;
+	request = smbdirect_connection_alloc_send_io(sc);
+	if (IS_ERR(request))
+		return PTR_ERR(request);
 
 	packet = smbdirect_send_io_payload(request);
 	packet->min_version = cpu_to_le16(SMBDIRECT_V1);
@@ -855,7 +848,6 @@ static int smbd_post_send_negotiate_req(struct smbdirect_socket *sc)
 	packet->max_fragmented_size =
 		cpu_to_le32(sp->max_fragmented_recv_size);
 
-	request->num_sge = 1;
 	request->sge[0].addr = ib_dma_map_single(
 				sc->ib.dev, (void *)packet,
 				sizeof(*packet), DMA_TO_DEVICE);
@@ -866,6 +858,7 @@ static int smbd_post_send_negotiate_req(struct smbdirect_socket *sc)
 
 	request->sge[0].length = sizeof(*packet);
 	request->sge[0].lkey = sc->ib.pd->local_dma_lkey;
+	request->num_sge = 1;
 
 	ib_dma_sync_single_for_device(
 		sc->ib.dev, request->sge[0].addr,
@@ -892,13 +885,11 @@ static int smbd_post_send_negotiate_req(struct smbdirect_socket *sc)
 	/* if we reach here, post send failed */
 	log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
 	atomic_dec(&sc->send_io.pending.count);
-	ib_dma_unmap_single(sc->ib.dev, request->sge[0].addr,
-		request->sge[0].length, DMA_TO_DEVICE);
 
 	smbdirect_connection_schedule_disconnect(sc, rc);
 
 dma_mapping_failed:
-	mempool_free(request, sc->send_io.mem.pool);
+	smbdirect_connection_free_send_io(request);
 	return rc;
 }
 
@@ -996,7 +987,7 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc,
 			       int *_remaining_data_length)
 {
 	struct smbdirect_socket_parameters *sp = &sc->parameters;
-	int i, rc;
+	int rc;
 	int header_length;
 	int data_length;
 	struct smbdirect_send_io *request;
@@ -1039,13 +1030,12 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc,
 		goto wait_credit;
 	}
 
-	request = mempool_alloc(sc->send_io.mem.pool, GFP_KERNEL);
-	if (!request) {
-		rc = -ENOMEM;
+	request = smbdirect_connection_alloc_send_io(sc);
+	if (IS_ERR(request)) {
+		rc = PTR_ERR(request);
 		goto err_alloc;
 	}
 
-	request->socket = sc;
 	memset(request->sge, 0, sizeof(request->sge));
 
 	/* Map the packet to DMA */
@@ -1135,13 +1125,7 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc,
 	wake_up(&sc->send_io.pending.dec_wait_queue);
 
 err_dma:
-	for (i = 0; i < request->num_sge; i++)
-		if (request->sge[i].addr)
-			ib_dma_unmap_single(sc->ib.dev,
-					    request->sge[i].addr,
-					    request->sge[i].length,
-					    DMA_TO_DEVICE);
-	mempool_free(request, sc->send_io.mem.pool);
+	smbdirect_connection_free_send_io(request);
 
 	/* roll back the granted receive credits */
 	atomic_sub(new_credits, &sc->recv_io.credits.count);
-- 
2.43.0