RDS: make m_rdma_op a member of rds_message

This eliminates a separate memory alloc, although
it is now necessary to add an "r_active" flag, since
it is no longer to use the m_rdma_op pointer as an
indicator of if an rdma op is present.

rdma SGs allocated from rm sg pool.

rds_rm_size also gets bigger. It's a little inefficient to
run through CMSGs twice, but it makes later steps a lot smoother.

Signed-off-by: Andy Grover <andy.grover@oracle.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/net/rds/message.c b/net/rds/message.c
index fb382fbb5b6f..4352ce79b376 100644
--- a/net/rds/message.c
+++ b/net/rds/message.c
@@ -69,8 +69,8 @@ static void rds_message_purge(struct rds_message *rm)
         }
         rm->data.m_nents = 0;
 
-        if (rm->rdma.m_rdma_op)
-                rds_rdma_free_op(rm->rdma.m_rdma_op);
+        if (rm->rdma.m_rdma_op.r_active)
+                rds_rdma_free_op(&rm->rdma.m_rdma_op);
         if (rm->rdma.m_rdma_mr)
                 rds_mr_put(rm->rdma.m_rdma_mr);
 }
@@ -259,14 +259,17 @@ struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned in
 {
         struct rds_message *rm;
         unsigned int i;
+        int num_sgs = ceil(total_len, PAGE_SIZE);
+        int extra_bytes = num_sgs * sizeof(struct scatterlist);
 
-        rm = rds_message_alloc(ceil(total_len, PAGE_SIZE), GFP_KERNEL);
+        rm = rds_message_alloc(extra_bytes, GFP_KERNEL);
         if (!rm)
                 return ERR_PTR(-ENOMEM);
 
         set_bit(RDS_MSG_PAGEVEC, &rm->m_flags);
         rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
         rm->data.m_nents = ceil(total_len, PAGE_SIZE);
+        rm->data.m_sg = rds_message_alloc_sgs(rm, num_sgs);
 
         for (i = 0; i < rm->data.m_nents; ++i) {
                 sg_set_page(&rm->data.m_sg[i],