[PATCH 5/5] RDMA/rxe: Move crc32 init code to rxe_icrc.c

Bob Pearson
2021-06-29T20:14:28Z

This patch collects the code from rxe_register_device() that sets
up the crc32 calculation into a subroutine rxe_icrc_init() in
rxe_icrc.c. This completes collecting all the code specific to computing
ICRC into one file with a simple set of APIs.
Minor cleanups in rxe_icrc.c to
Comments
byte order types

Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
---
drivers/infiniband/sw/rxe/rxe.h | 1 -
drivers/infiniband/sw/rxe/rxe_icrc.c | 75 +++++++++++++++++----------
drivers/infiniband/sw/rxe/rxe_loc.h | 1 +
drivers/infiniband/sw/rxe/rxe_verbs.c | 11 ++--
4 files changed, 53 insertions(+), 35 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe.h b/drivers/infiniband/sw/rxe/rxe.h
index 65a73c1c8b35..1bb3fb618bf5 100644
--- a/drivers/infiniband/sw/rxe/rxe.h
+++ b/drivers/infiniband/sw/rxe/rxe.h
@@ -14,7 +14,6 @@

#include <linux/module.h>
#include <linux/skbuff.h>
-#include <linux/crc32.h>

#include <rdma/ib_verbs.h>
#include <rdma/ib_user_verbs.h>
diff --git a/drivers/infiniband/sw/rxe/rxe_icrc.c b/drivers/infiniband/sw/rxe/rxe_icrc.c
index e116c63d7b84..4f311798d682 100644
--- a/drivers/infiniband/sw/rxe/rxe_icrc.c
+++ b/drivers/infiniband/sw/rxe/rxe_icrc.c
@@ -4,34 +4,59 @@
* Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
*/

+#include <linux/crc32.h>
#include "rxe.h"
#include "rxe_loc.h"

/**
- * rxe_crc32 - Compute incremental crc32 for a contiguous segment
+ * rxe_icrc_init - Initialize crypto function for computing crc32
+ * @rxe: rdma_rxe device object
+ *
+ * Returns 0 on success else an error
+ */
+int rxe_icrc_init(struct rxe_dev *rxe)
+{
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash("crc32", 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_err("failed to init crc32 algorithm err:%ld\n",
+ PTR_ERR(tfm));
+ return PTR_ERR(tfm);
+ }
+
+ rxe->tfm = tfm;
+
+ return 0;
+}
+
+/**
+ * rxe_crc32 - Compute cumulative crc32 for a contiguous segment
* @rxe: rdma_rxe device object
* @crc: starting crc32 value from previous segments
* @addr: starting address of segment
* @len: length of the segment in bytes
*
- * Returns the crc32 checksum of the segment starting from crc.
+ * Returns the crc32 cumulative checksum including the segment starting
+ * from crc.
*/
-static u32 rxe_crc32(struct rxe_dev *rxe, u32 crc, void *addr, size_t len)
+static __be32 rxe_crc32(struct rxe_dev *rxe, __be32 crc, void *addr,
+ size_t len)
{
- u32 icrc;
+ __be32 icrc;
int err;

SHASH_DESC_ON_STACK(shash, rxe->tfm);

shash->tfm = rxe->tfm;
- *(u32 *)shash_desc_ctx(shash) = crc;
+ *(__be32 *)shash_desc_ctx(shash) = crc;
err = crypto_shash_update(shash, addr, len);
if (unlikely(err)) {
pr_warn_ratelimited("failed crc calculation, err: %d\n", err);
return crc32_le(crc, addr, len);
}

- icrc = *(u32 *)shash_desc_ctx(shash);
+ icrc = *(__be32 *)shash_desc_ctx(shash);
barrier_data(shash_desc_ctx(shash));

return icrc;
@@ -39,19 +64,16 @@ static u32 rxe_crc32(struct rxe_dev *rxe, u32 crc, void *addr, size_t len)

/**
* rxe_icrc_hdr - Compute a partial ICRC for the IB transport headers.
- * @pkt: Information about the current packet
- * @skb: The packet buffer
+ * @pkt: packet information
+ * @skb: packet buffer
*
* Returns the partial ICRC
*/
static u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb)
{
- unsigned int bth_offset = 0;
- struct iphdr *ip4h = NULL;
- struct ipv6hdr *ip6h = NULL;
struct udphdr *udph;
struct rxe_bth *bth;
- int crc;
+ __be32 crc;
int length;
int hdr_size = sizeof(struct udphdr) +
(skb->protocol == htons(ETH_P_IP) ?
@@ -69,6 +91,8 @@ static u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb)
crc = 0xdebb20e3;

if (skb->protocol == htons(ETH_P_IP)) { /* IPv4 */
+ struct iphdr *ip4h = NULL;
+
memcpy(pshdr, ip_hdr(skb), hdr_size);
ip4h = (struct iphdr *)pshdr;
udph = (struct udphdr *)(ip4h + 1);
@@ -77,6 +101,8 @@ static u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb)
ip4h->check = CSUM_MANGLED_0;
ip4h->tos = 0xff;
} else { /* IPv6 */
+ struct ipv6hdr *ip6h = NULL;
+
memcpy(pshdr, ipv6_hdr(skb), hdr_size);
ip6h = (struct ipv6hdr *)pshdr;
udph = (struct udphdr *)(ip6h + 1);
@@ -85,12 +111,9 @@ static u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb)
ip6h->priority = 0xf;
ip6h->hop_limit = 0xff;
}
- udph->check = CSUM_MANGLED_0;
-
- bth_offset += hdr_size;

- memcpy(&pshdr[bth_offset], pkt->hdr, RXE_BTH_BYTES);
- bth = (struct rxe_bth *)&pshdr[bth_offset];
+ bth = (struct rxe_bth *)(udph + 1);
+ memcpy(bth, pkt->hdr, RXE_BTH_BYTES);

/* exclude bth.resv8a */
bth->qpn |= cpu_to_be32(~BTH_QPN_MASK);
@@ -115,18 +138,18 @@ int rxe_icrc_check(struct sk_buff *skb)
{
struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
__be32 *icrcp;
- u32 pkt_icrc;
- u32 icrc;
+ __be32 packet_icrc;
+ __be32 computed_icrc;

icrcp = (__be32 *)(pkt->hdr + pkt->paylen - RXE_ICRC_SIZE);
- pkt_icrc = be32_to_cpu(*icrcp);
+ packet_icrc = *icrcp;

- icrc = rxe_icrc_hdr(pkt, skb);
- icrc = rxe_crc32(pkt->rxe, icrc, (u8 *)payload_addr(pkt),
- payload_size(pkt) + bth_pad(pkt));
- icrc = (__force u32)cpu_to_be32(~icrc);
+ computed_icrc = rxe_icrc_hdr(pkt, skb);
+ computed_icrc = rxe_crc32(pkt->rxe, computed_icrc,
+ (u8 *)payload_addr(pkt), payload_size(pkt) + bth_pad(pkt));
+ computed_icrc = ~computed_icrc;

- if (unlikely(icrc != pkt_icrc)) {
+ if (unlikely(computed_icrc != packet_icrc)) {
if (skb->protocol == htons(ETH_P_IPV6))
pr_warn_ratelimited("bad ICRC from %pI6c\n",
&ipv6_hdr(skb)->saddr);
@@ -150,7 +173,7 @@ int rxe_icrc_check(struct sk_buff *skb)
void rxe_icrc_generate(struct rxe_pkt_info *pkt, struct sk_buff *skb)
{
__be32 *icrcp;
- u32 icrc;
+ __be32 icrc;

icrcp = (__be32 *)(pkt->hdr + pkt->paylen - RXE_ICRC_SIZE);
icrc = rxe_icrc_hdr(pkt, skb);
diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h
index b08689b664ec..f98378f8ff31 100644
--- a/drivers/infiniband/sw/rxe/rxe_loc.h
+++ b/drivers/infiniband/sw/rxe/rxe_loc.h
@@ -193,6 +193,7 @@ int rxe_requester(void *arg);
int rxe_responder(void *arg);

/* rxe_icrc.c */
+int rxe_icrc_init(struct rxe_dev *rxe);
int rxe_icrc_check(struct sk_buff *skb);
void rxe_icrc_generate(struct rxe_pkt_info *pkt, struct sk_buff *skb);

diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
index c223959ac174..f7b1a1f64c13 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -1154,7 +1154,6 @@ int rxe_register_device(struct rxe_dev *rxe, const char *ibdev_name)
{
int err;
struct ib_device *dev = &rxe->ib_dev;
- struct crypto_shash *tfm;

strscpy(dev->node_desc, "rxe", sizeof(dev->node_desc));

@@ -1173,13 +1172,9 @@ int rxe_register_device(struct rxe_dev *rxe, const char *ibdev_name)
if (err)
return err;

- tfm = crypto_alloc_shash("crc32", 0, 0);
- if (IS_ERR(tfm)) {
- pr_err("failed to allocate crc algorithm err:%ld\n",
- PTR_ERR(tfm));
- return PTR_ERR(tfm);
- }
- rxe->tfm = tfm;
+ err = rxe_icrc_init(rxe);
+ if (err)
+ return err;

err = ib_register_device(dev, ibdev_name, NULL);
if (err)
--
2.30.2