mirrors/scst
1
0
Fork 0
mirror of https://github.com/SCST-project/scst.git synced 2026-08-19 21:56:31 +00:00
Code Issues Packages Projects Releases Wiki Activity

ib_srpt: Micro-optimize SRP_CMD parsing

Browse Source 
git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@5350 d57e44dd-8a1f-0410-8b47-8ef2f437770f
This commit is contained in:
Bart Van Assche
2014-03-20 15:18:38 +00:00
parent 91358f846c
commit bfae911b39
1 changed files with 15 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files
srpt/src/ib_srpt.c
+15 -7
View File
@@ -1057,6 +1057,7 @@ static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
struct srp_direct_buf *db;
unsigned add_cdb_offset;
int ret;
u8 fmt;
/*
* The pointer computations below will only be compiled correctly
@@ -1081,13 +1082,18 @@ static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
* buffer descriptor format, and the highest four bits contain the
* DATA-OUT buffer descriptor format.
*/
*dir = SCST_DATA_NONE;
if (srp_cmd->buf_fmt & 0xf)
fmt = srp_cmd->buf_fmt;
if (fmt & 0xf) {
/* DATA-IN: transfer data from target to initiator (read). */
*dir = SCST_DATA_READ;
else if (srp_cmd->buf_fmt >> 4)
fmt = fmt & 0xf;
} else if (fmt >> 4) {
/* DATA-OUT: transfer data from initiator to target (write). */
*dir = SCST_DATA_WRITE;
fmt = fmt >> 4;
} else {
*dir = SCST_DATA_NONE;
}
/*
* According to the SRP spec, the lower two bits of the 'ADDITIONAL
@@ -1095,8 +1101,7 @@ static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
* is four times the value specified in bits 3..7. Hence the "& ~3".
*/
add_cdb_offset = srp_cmd->add_cdb_len & ~3;
if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) ||
((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) {
if (fmt == SRP_DATA_DESC_DIRECT) {
ioctx->n_rbuf = 1;
ioctx->rbufs = &ioctx->single_rbuf;
@@ -1104,8 +1109,7 @@ static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
+ add_cdb_offset);
memcpy(ioctx->rbufs, db, sizeof(*db));
*data_len = be32_to_cpu(db->len);
} else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) ||
((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) {
} else if (fmt == SRP_DATA_DESC_INDIRECT) {
idb = (struct srp_indirect_buf *)(srp_cmd->add_data
+ add_cdb_offset);
@@ -1139,7 +1143,11 @@ static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
db = idb->desc_list;
memcpy(ioctx->rbufs, db, ioctx->n_rbuf * sizeof(*db));
*data_len = be32_to_cpu(idb->len);
} else if (fmt != 0) {
PRINT_ERROR("Unsupported data format %d\n", fmt);
ret = -EINVAL;
}
out:
return ret;
}