[PATCH for-next v5 04/10] RDMA/rxe: Add ib_alloc_mw and ib_dealloc_mw verbs

Bob Pearson
2021-04-22T16:13:53Z

Add ib_alloc_mw and ib_dealloc_mw verbs APIs.

Added new file rxe_mw.c focused on MWs.
Changed the 8 bit random key generator.
Added a cleanup routine for MWs.
Added verbs routines to ib_device_ops.

Signed-off-by: Bob Pearson <rpearson@hpe.com>
---
drivers/infiniband/sw/rxe/Makefile | 1 +
drivers/infiniband/sw/rxe/rxe_loc.h | 6 +++
drivers/infiniband/sw/rxe/rxe_mr.c | 20 +++++-----
drivers/infiniband/sw/rxe/rxe_mw.c | 53 +++++++++++++++++++++++++++
drivers/infiniband/sw/rxe/rxe_pool.c | 1 +
drivers/infiniband/sw/rxe/rxe_verbs.c | 3 ++
drivers/infiniband/sw/rxe/rxe_verbs.h | 2 +
7 files changed, 75 insertions(+), 11 deletions(-)
create mode 100644 drivers/infiniband/sw/rxe/rxe_mw.c

diff --git a/drivers/infiniband/sw/rxe/Makefile b/drivers/infiniband/sw/rxe/Makefile
index 66af72dca759..1e24673e9318 100644
--- a/drivers/infiniband/sw/rxe/Makefile
+++ b/drivers/infiniband/sw/rxe/Makefile
@@ -15,6 +15,7 @@ rdma_rxe-y := \
rxe_qp.o \
rxe_cq.o \
rxe_mr.o \
+ rxe_mw.o \
rxe_opcode.o \
rxe_mmap.o \
rxe_icrc.o \
diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h
index ef8061d2fbe0..edf575930a98 100644
--- a/drivers/infiniband/sw/rxe/rxe_loc.h
+++ b/drivers/infiniband/sw/rxe/rxe_loc.h
@@ -76,6 +76,7 @@ enum copy_direction {
from_mr_obj,
};

+u8 rxe_get_next_key(u32 last_key);
void rxe_mr_init_dma(struct rxe_pd *pd, int access, struct rxe_mr *mr);

int rxe_mr_init_user(struct rxe_pd *pd, u64 start, u64 length, u64 iova,
@@ -106,6 +107,11 @@ void rxe_mr_cleanup(struct rxe_pool_entry *arg);

int advance_dma_data(struct rxe_dma_info *dma, unsigned int length);

+/* rxe_mw.c */
+int rxe_alloc_mw(struct ib_mw *ibmw, struct ib_udata *udata);
+int rxe_dealloc_mw(struct ib_mw *ibmw);
+void rxe_mw_cleanup(struct rxe_pool_entry *arg);
+
/* rxe_net.c */
void rxe_loopback(struct sk_buff *skb);
int rxe_send(struct rxe_pkt_info *pkt, struct sk_buff *skb);
diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
index 9f63947bab12..7f2cfc1ce659 100644
--- a/drivers/infiniband/sw/rxe/rxe_mr.c
+++ b/drivers/infiniband/sw/rxe/rxe_mr.c
@@ -7,19 +7,17 @@
#include "rxe.h"
#include "rxe_loc.h"

-/*
- * lfsr (linear feedback shift register) with period 255
+/* Return a random 8 bit key value that is
+ * different than the last_key. Set last_key to -1
+ * if this is the first key for an MR or MW
*/
-static u8 rxe_get_key(void)
+u8 rxe_get_next_key(u32 last_key)
{
- static u32 key = 1;
-
- key = key << 1;
-
- key |= (0 != (key & 0x100)) ^ (0 != (key & 0x10))
- ^ (0 != (key & 0x80)) ^ (0 != (key & 0x40));
+ u8 key;

- key &= 0xff;
+ do {
+ get_random_bytes(&key, 1);
+ } while (key == last_key);

return key;
}
@@ -47,7 +45,7 @@ int mr_check_range(struct rxe_mr *mr, u64 iova, size_t length)

static void rxe_mr_init(int access, struct rxe_mr *mr)
{
- u32 lkey = mr->pelem.index << 8 | rxe_get_key();
+ u32 lkey = mr->pelem.index << 8 | rxe_get_next_key(-1);
u32 rkey = (access & IB_ACCESS_REMOTE) ? lkey : 0;

mr->ibmr.lkey = lkey;
diff --git a/drivers/infiniband/sw/rxe/rxe_mw.c b/drivers/infiniband/sw/rxe/rxe_mw.c
new file mode 100644
index 000000000000..69128e298d44
--- /dev/null
+++ b/drivers/infiniband/sw/rxe/rxe_mw.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/*
+ * Copyright (c) 2020 Hewlett Packard Enterprise, Inc. All rights reserved.
+ */
+
+#include "rxe.h"
+
+int rxe_alloc_mw(struct ib_mw *ibmw, struct ib_udata *udata)
+{
+ struct rxe_mw *mw = to_rmw(ibmw);
+ struct rxe_pd *pd = to_rpd(ibmw->pd);
+ struct rxe_dev *rxe = to_rdev(ibmw->device);
+ int ret;
+
+ rxe_add_ref(pd);
+
+ ret = rxe_add_to_pool(&rxe->mw_pool, mw);
+ if (ret) {
+ rxe_drop_ref(pd);
+ return ret;
+ }
+
+ rxe_add_index(mw);
+ ibmw->rkey = (mw->pelem.index << 8) | rxe_get_next_key(-1);
+ mw->state = (mw->ibmw.type == IB_MW_TYPE_2) ?
+ RXE_MW_STATE_FREE : RXE_MW_STATE_VALID;
+ spin_lock_init(&mw->lock);
+
+ return 0;
+}
+
+int rxe_dealloc_mw(struct ib_mw *ibmw)
+{
+ struct rxe_mw *mw = to_rmw(ibmw);
+ struct rxe_pd *pd = to_rpd(ibmw->pd);
+ unsigned long flags;
+
+ spin_lock_irqsave(&mw->lock, flags);
+ mw->state = RXE_MW_STATE_INVALID;
+ spin_unlock_irqrestore(&mw->lock, flags);
+
+ rxe_drop_ref(mw);
+ rxe_drop_ref(pd);
+
+ return 0;
+}
+
+void rxe_mw_cleanup(struct rxe_pool_entry *elem)
+{
+ struct rxe_mw *mw = container_of(elem, typeof(*mw), pelem);
+
+ rxe_drop_index(mw);
+}
diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
index 2b795e2fc4b3..5b3277e8c35d 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.c
+++ b/drivers/infiniband/sw/rxe/rxe_pool.c
@@ -65,6 +65,7 @@ struct rxe_type_info rxe_type_info[RXE_NUM_TYPES] = {
.name = "rxe-mw",
.size = sizeof(struct rxe_mw),
.elem_offset = offsetof(struct rxe_mw, pelem),
+ .cleanup = rxe_mw_cleanup,
.flags = RXE_POOL_INDEX | RXE_POOL_NO_ALLOC,
.max_index = RXE_MAX_MW_INDEX,
.min_index = RXE_MIN_MW_INDEX,
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
index aeb5e232c195..fff81bf78a86 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -1060,6 +1060,7 @@ static const struct ib_device_ops rxe_dev_ops = {

.alloc_hw_stats = rxe_ib_alloc_hw_stats,
.alloc_mr = rxe_alloc_mr,
+ .alloc_mw = rxe_alloc_mw,
.alloc_pd = rxe_alloc_pd,
.alloc_ucontext = rxe_alloc_ucontext,
.attach_mcast = rxe_attach_mcast,
@@ -1069,6 +1070,7 @@ static const struct ib_device_ops rxe_dev_ops = {
.create_srq = rxe_create_srq,
.create_user_ah = rxe_create_ah,
.dealloc_driver = rxe_dealloc,
+ .dealloc_mw = rxe_dealloc_mw,
.dealloc_pd = rxe_dealloc_pd,
.dealloc_ucontext = rxe_dealloc_ucontext,
.dereg_mr = rxe_dereg_mr,
@@ -1106,6 +1108,7 @@ static const struct ib_device_ops rxe_dev_ops = {

INIT_RDMA_OBJ_SIZE(ib_ah, rxe_ah, ibah),
INIT_RDMA_OBJ_SIZE(ib_cq, rxe_cq, ibcq),
+ INIT_RDMA_OBJ_SIZE(ib_mw, rxe_mw, ibmw),
INIT_RDMA_OBJ_SIZE(ib_pd, rxe_pd, ibpd),
INIT_RDMA_OBJ_SIZE(ib_srq, rxe_srq, ibsrq),
INIT_RDMA_OBJ_SIZE(ib_ucontext, rxe_ucontext, ibuc),
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
index 8d32e3f50813..c8597ae8c833 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -323,6 +323,8 @@ enum rxe_mw_state {
struct rxe_mw {
struct ib_mw ibmw;
struct rxe_pool_entry pelem;
+ spinlock_t lock;
+ enum rxe_mw_state state;
};

struct rxe_mc_grp {
--
2.27.0