RDS: Assume recv->r_frag is always NULL in refill_one()
refill_one() should never be called on a recv struct that
doesn't need a new r_frag allocated. Add a WARN and remove
conditional around r_frag alloc code.
Also, add a comment to explain why r_ibinc may or may not
need refilling.
Signed-off-by: Andy Grover <andy.grover@oracle.com>
diff --git a/net/rds/ib_recv.c b/net/rds/ib_recv.c
index f6dbf16e..5c7e6ac 100644
--- a/net/rds/ib_recv.c
+++ b/net/rds/ib_recv.c
@@ -126,6 +126,10 @@
struct ib_sge *sge;
int ret = -ENOMEM;
+ /*
+ * ibinc was taken from recv if recv contained the start of a message.
+ * recvs that were continuations will still have this allocated.
+ */
if (!recv->r_ibinc) {
if (!atomic_add_unless(&rds_ib_allocation, 1, rds_ib_sysctl_max_recv_allocation)) {
rds_ib_stats_inc(s_ib_rx_alloc_limit);
@@ -140,19 +144,18 @@
rds_inc_init(&recv->r_ibinc->ii_inc, conn, conn->c_faddr);
}
- if (!recv->r_frag) {
- recv->r_frag = kmem_cache_alloc(rds_ib_frag_slab, GFP_NOWAIT);
- if (!recv->r_frag)
- goto out;
- INIT_LIST_HEAD(&recv->r_frag->f_item);
- sg_init_table(&recv->r_frag->f_sg, 1);
- ret = rds_page_remainder_alloc(&recv->r_frag->f_sg,
- RDS_FRAG_SIZE, GFP_NOWAIT);
- if (ret) {
- kmem_cache_free(rds_ib_frag_slab, recv->r_frag);
- recv->r_frag = NULL;
- goto out;
- }
+ WARN_ON(recv->r_frag); /* leak! */
+ recv->r_frag = kmem_cache_alloc(rds_ib_frag_slab, GFP_NOWAIT);
+ if (!recv->r_frag)
+ goto out;
+ INIT_LIST_HEAD(&recv->r_frag->f_item);
+ sg_init_table(&recv->r_frag->f_sg, 1);
+ ret = rds_page_remainder_alloc(&recv->r_frag->f_sg,
+ RDS_FRAG_SIZE, GFP_NOWAIT);
+ if (ret) {
+ kmem_cache_free(rds_ib_frag_slab, recv->r_frag);
+ recv->r_frag = NULL;
+ goto out;
}
ret = ib_dma_map_sg(ic->i_cm_id->device, &recv->r_frag->f_sg,