[PATCH 21/21] staging: lustre: socklnd: simplify ksnc_rx_iov_space

From: NeilBrown
Date: Mon Feb 19 2018 - 21:26:54 EST


ksnc_rx_iov_space is currently a union of two arrays,
one of 'struct kvec', the other of 'struct bio_vec'.

The 'struct bio_vec' option is never used. The
array of kvec is used to read in a packet header, or
to read data that needs to be skipped so as to synchronize
with a packet boundary.
In each case the target memory location is a virtual address,
never a page, so 'struct bio_vec' is never needed.

When we read into a page, different code steps up a separate
array of 'struct bio_vec'.

So remove the bio_vec option, and remove the union ksock_rxiovspace..

Signed-off-by: NeilBrown <neilb@xxxxxxxx>
---
.../staging/lustre/lnet/klnds/socklnd/socklnd.h | 11 +----------
.../staging/lustre/lnet/klnds/socklnd/socklnd_cb.c | 4 ++--
2 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd.h b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd.h
index d50ebdf863fa..570f54ed57b1 100644
--- a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd.h
+++ b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd.h
@@ -304,15 +304,6 @@ struct ksock_tx { /* transmit packet */

/* network zero copy callback descriptor embedded in struct ksock_tx */

-/*
- * space for the rx frag descriptors; we either read a single contiguous
- * header, or up to LNET_MAX_IOV frags of payload of either type.
- */
-union ksock_rxiovspace {
- struct kvec iov[LNET_MAX_IOV];
- struct bio_vec kiov[LNET_MAX_IOV];
-};
-
#define SOCKNAL_RX_KSM_HEADER 1 /* reading ksock message header */
#define SOCKNAL_RX_LNET_HEADER 2 /* reading lnet message header */
#define SOCKNAL_RX_PARSE 3 /* Calling lnet_parse() */
@@ -359,7 +350,7 @@ struct ksock_conn {
__u8 ksnc_rx_state; /* what is being read */
int ksnc_rx_nob_left; /* # bytes to next hdr/body */
struct iov_iter ksnc_rx_to; /* copy destination */
- union ksock_rxiovspace ksnc_rx_iov_space; /* space for frag descriptors */
+ struct kvec ksnc_rx_iov_space[LNET_MAX_IOV]; /* space for frag descriptors */
__u32 ksnc_rx_csum; /* partial checksum for incoming
* data
*/
diff --git a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_cb.c b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_cb.c
index 6ab002c006ab..036fecbcede8 100644
--- a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_cb.c
+++ b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_cb.c
@@ -986,7 +986,7 @@ int
ksocknal_new_packet(struct ksock_conn *conn, int nob_to_skip)
{
static char ksocknal_slop_buffer[4096];
- struct kvec *kvec = (struct kvec *)&conn->ksnc_rx_iov_space;
+ struct kvec *kvec = conn->ksnc_rx_iov_space;

int nob;
unsigned int niov;
@@ -1059,7 +1059,7 @@ ksocknal_new_packet(struct ksock_conn *conn, int nob_to_skip)
static int
ksocknal_process_receive(struct ksock_conn *conn)
{
- struct kvec *kvec = (struct kvec *)&conn->ksnc_rx_iov_space;
+ struct kvec *kvec = conn->ksnc_rx_iov_space;
struct lnet_hdr *lhdr;
struct lnet_process_id *id;
int rc;