For map support we will need to send and receive control messages.
Add basic support for sending a message to FW, and waiting for a
reply.
Control messages are tagged with a 16 bit ID. Add a simple ID
allocator and make sure we don't allow too many messages in flight,
to avoid request <> reply mismatches.
Signed-off-by: Jakub Kicinski <jakub.kicin...@netronome.com>
Reviewed-by: Quentin Monnet <quentin.mon...@netronome.com>
---
drivers/net/ethernet/netronome/nfp/Makefile | 1 +
drivers/net/ethernet/netronome/nfp/bpf/cmsg.c | 238 +++++++++++++++++++++
drivers/net/ethernet/netronome/nfp/bpf/fw.h | 22 ++
drivers/net/ethernet/netronome/nfp/bpf/main.c | 5 +
drivers/net/ethernet/netronome/nfp/bpf/main.h | 23 ++
drivers/net/ethernet/netronome/nfp/nfp_app.h | 9 +
drivers/net/ethernet/netronome/nfp/nfp_net.h | 12 ++
.../net/ethernet/netronome/nfp/nfp_net_common.c | 7 +
8 files changed, 317 insertions(+)
create mode 100644 drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
diff --git a/drivers/net/ethernet/netronome/nfp/Makefile
b/drivers/net/ethernet/netronome/nfp/Makefile
index 6e5ef984398b..064f00e23a19 100644
--- a/drivers/net/ethernet/netronome/nfp/Makefile
+++ b/drivers/net/ethernet/netronome/nfp/Makefile
@@ -44,6 +44,7 @@ endif
ifeq ($(CONFIG_BPF_SYSCALL),y)
nfp-objs += \
+ bpf/cmsg.o \
bpf/main.o \
bpf/offload.o \
bpf/verifier.o \
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
new file mode 100644
index 000000000000..46753ee9f7c5
--- /dev/null
+++ b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
@@ -0,0 +1,238 @@
+/*
+ * Copyright (C) 2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below. You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/bitops.h>
+#include <linux/bug.h>
+#include <linux/jiffies.h>
+#include <linux/skbuff.h>
+#include <linux/wait.h>
+
+#include "../nfp_app.h"
+#include "../nfp_net.h"
+#include "fw.h"
+#include "main.h"
+
+#define cmsg_warn(bpf, msg...) nn_dp_warn(&(bpf)->app->ctrl->dp, msg)
+
+#define NFP_BPF_TAG_ALLOC_SPAN (U16_MAX / 4)
+
+static bool nfp_bpf_all_tags_busy(struct nfp_app_bpf *bpf)
+{
+ u16 used_tags;
+
+ used_tags = bpf->tag_alloc_next - bpf->tag_alloc_last;
+
+ return used_tags > NFP_BPF_TAG_ALLOC_SPAN;
+}
+
+static int nfp_bpf_alloc_tag(struct nfp_app_bpf *bpf)
+{
+ /* All FW communication for BPF is request-reply. To make sure we
+ * don't reuse the message ID too early after timeout - limit the
+ * number of requests in flight.
+ */
+ if (nfp_bpf_all_tags_busy(bpf)) {
+ cmsg_warn(bpf, "all FW request contexts busy!\n");
+ return -EAGAIN;
+ }
+
+ WARN_ON(__test_and_set_bit(bpf->tag_alloc_next, bpf->tag_allocator));
+ return bpf->tag_alloc_next++;
+}
+
+static void nfp_bpf_free_tag(struct nfp_app_bpf *bpf, u16 tag)
+{
+ WARN_ON(!__test_and_clear_bit(tag, bpf->tag_allocator));
+
+ while (!test_bit(bpf->tag_alloc_last, bpf->tag_allocator) &&
+ bpf->tag_alloc_last != bpf->tag_alloc_next)
+ bpf->tag_alloc_last++;
+}
+
+static unsigned int nfp_bpf_cmsg_get_tag(struct sk_buff *skb)
+{
+ struct cmsg_hdr *hdr;
+
+ hdr = (struct cmsg_hdr *)skb->data;
+
+ return be16_to_cpu(hdr->tag);
+}
+
+static struct sk_buff *__nfp_bpf_reply(struct nfp_app_bpf *bpf, u16 tag)
+{
+ unsigned int msg_tag;
+ struct sk_buff *skb;
+
+ skb_queue_walk(&bpf->cmsg_replies, skb) {
+ msg_tag = nfp_bpf_cmsg_get_tag(skb);
+ if (msg_tag == tag) {
+ nfp_bpf_free_tag(bpf, tag);
+ __skb_unlink(skb, &bpf->cmsg_replies);
+ return skb;
+ }
+ }
+
+ return NULL;
+}
+
+static struct sk_buff *nfp_bpf_reply(struct nfp_app_bpf *bpf, u16 tag)
+{
+ struct sk_buff *skb;
+
+ nfp_ctrl_lock(bpf->app->ctrl);
+ skb = __nfp_bpf_reply(bpf, tag);
+ nfp_ctrl_unlock(bpf->app->ctrl);
+
+ return skb;
+}
+
+static struct sk_buff *nfp_bpf_reply_drop_tag(struct nfp_app_bpf *bpf, u16 tag)
+{
+ struct sk_buff *skb;
+
+ nfp_ctrl_lock(bpf->app->ctrl);
+ skb = __nfp_bpf_reply(bpf, tag);
+ if (!skb)
+ nfp_bpf_free_tag(bpf, tag);
+ nfp_ctrl_unlock(bpf->app->ctrl);
+
+ return skb;
+}
+
+static struct sk_buff *
+nfp_bpf_cmsg_wait_reply(struct nfp_app_bpf *bpf, enum nfp_bpf_cmsg_type type,
+ int tag)
+{
+ struct sk_buff *skb;
+ int err;
+
+ err = wait_event_interruptible_timeout(bpf->cmsg_wq,
+ skb = nfp_bpf_reply(bpf, tag),
+ msecs_to_jiffies(5000));
+ /* We didn't get a response - try last time and atomically drop
+ * the tag even if no response is matched.
+ */
+ if (!skb)
+ skb = nfp_bpf_reply_drop_tag(bpf, tag);
+ if (err < 0) {
+ cmsg_warn(bpf, "%s waiting for response to 0x%02x: %d\n",
+ err == ERESTARTSYS ? "interrupted" : "error",
+ type, err);
+ return ERR_PTR(err);
+ }
+ if (!skb) {
+ cmsg_warn(bpf, "timeout waiting for response to 0x%02x\n",
+ type);
+ return ERR_PTR(-ETIMEDOUT);
+ }
+
+ return skb;
+}
+
+struct sk_buff *
+nfp_bpf_cmsg_communicate(struct nfp_app_bpf *bpf, struct sk_buff *skb,
+ enum nfp_bpf_cmsg_type type, unsigned int reply_size)
+{
+ struct cmsg_hdr *hdr;
+ int tag;
+
+ nfp_ctrl_lock(bpf->app->ctrl);
+ tag = nfp_bpf_alloc_tag(bpf);
+ if (tag < 0) {
+ nfp_ctrl_unlock(bpf->app->ctrl);
+ dev_kfree_skb_any(skb);
+ return ERR_PTR(tag);
+ }
+
+ hdr = (void *)skb->data;
+ hdr->ver = CMSG_MAP_ABI_VERSION;
+ hdr->type = type;
+ hdr->tag = cpu_to_be16(tag);
+
+ __nfp_app_ctrl_tx(bpf->app, skb);
+
+ nfp_ctrl_unlock(bpf->app->ctrl);
+
+ skb = nfp_bpf_cmsg_wait_reply(bpf, type, tag);
+ if (IS_ERR(skb))
+ return skb;
+
+ hdr = (struct cmsg_hdr *)skb->data;
+ /* 0 reply_size means caller will do the validation */
+ if (reply_size && skb->len != reply_size) {
+ cmsg_warn(bpf, "cmsg drop - wrong size %d != %d!\n",
+ skb->len, reply_size);
+ goto err_free;
+ }
+ if (hdr->type != __CMSG_REPLY(type)) {
+ cmsg_warn(bpf, "cmsg drop - wrong type 0x%02x != 0x%02lx!\n",
+ hdr->type, __CMSG_REPLY(type));
+ goto err_free;
+ }
+
+ return skb;
+err_free:
+ dev_kfree_skb_any(skb);
+ return ERR_PTR(-EIO);
+}
+
+void nfp_bpf_ctrl_msg_rx(struct nfp_app *app, struct sk_buff *skb)
+{
+ struct nfp_app_bpf *bpf = app->priv;
+ unsigned int tag;
+
+ if (unlikely(skb->len < sizeof(struct cmsg_reply_map_simple))) {
+ cmsg_warn(bpf, "cmsg drop - too short %d!\n", skb->len);
+ goto err_free;
+ }
+
+ nfp_ctrl_lock(bpf->app->ctrl);
+
+ tag = nfp_bpf_cmsg_get_tag(skb);
+ if (unlikely(!test_bit(tag, bpf->tag_allocator))) {
+ cmsg_warn(bpf, "cmsg drop - no one is waiting for tag %u!\n",
+ tag);
+ goto err_unlock;
+ }
+
+ __skb_queue_tail(&bpf->cmsg_replies, skb);
+ wake_up_interruptible_all(&bpf->cmsg_wq);
+
+ nfp_ctrl_unlock(bpf->app->ctrl);
+
+ return;
+err_unlock:
+ nfp_ctrl_unlock(bpf->app->ctrl);
+err_free:
+ dev_kfree_skb_any(skb);
+}
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/fw.h
b/drivers/net/ethernet/netronome/nfp/bpf/fw.h
index 7206aa1522db..107676b34760 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/fw.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/fw.h
@@ -51,4 +51,26 @@ struct nfp_bpf_cap_tlv_adjust_head {
#define NFP_BPF_ADJUST_HEAD_NO_META BIT(0)
+/*
+ * Types defined for map related control messages
+ */
+#define CMSG_MAP_ABI_VERSION 1
+
+enum nfp_bpf_cmsg_type {
+ __CMSG_TYPE_MAP_MAX,
+};
+
+#define CMSG_TYPE_MAP_REPLY_BIT 7
+#define __CMSG_REPLY(req) (BIT(CMSG_TYPE_MAP_REPLY_BIT) | (req))
+
+struct cmsg_hdr {
+ u8 type;
+ u8 ver;
+ __be16 tag;
+};
+
+struct cmsg_reply_map_simple {
+ struct cmsg_hdr hdr;
+ __be32 rc;
+};
#endif
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.c
b/drivers/net/ethernet/netronome/nfp/bpf/main.c
index c9fd7d417d1a..a14368c6449f 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.c
@@ -313,6 +313,8 @@ static int nfp_bpf_init(struct nfp_app *app)
bpf->app = app;
app->priv = bpf;
+ skb_queue_head_init(&bpf->cmsg_replies);
+ init_waitqueue_head(&bpf->cmsg_wq);
INIT_LIST_HEAD(&bpf->map_list);
err = nfp_bpf_parse_capabilities(app);
@@ -330,6 +332,7 @@ static void nfp_bpf_clean(struct nfp_app *app)
{
struct nfp_app_bpf *bpf = app->priv;
+ WARN_ON(!skb_queue_empty(&bpf->cmsg_replies));
WARN_ON(!list_empty(&bpf->map_list));
kfree(bpf);
}
@@ -348,6 +351,8 @@ const struct nfp_app_type app_bpf = {
.vnic_alloc = nfp_bpf_vnic_alloc,
.vnic_free = nfp_bpf_vnic_free,
+ .ctrl_msg_rx = nfp_bpf_ctrl_msg_rx,
+
.setup_tc = nfp_bpf_setup_tc,
.tc_busy = nfp_bpf_tc_busy,
.bpf = nfp_ndo_bpf,
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h
b/drivers/net/ethernet/netronome/nfp/bpf/main.h
index 23763b22f8fc..e00a7de2a9c2 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h
@@ -37,10 +37,14 @@
#include <linux/bitfield.h>
#include <linux/bpf.h>
#include <linux/bpf_verifier.h>
+#include <linux/kernel.h>
#include <linux/list.h>
+#include <linux/skbuff.h>
#include <linux/types.h>
+#include <linux/wait.h>
#include "../nfp_asm.h"
+#include "fw.h"
/* For relocation logic use up-most byte of branch instruction as scratch
* area. Remember to clear this before sending instructions to HW!
@@ -93,6 +97,13 @@ enum pkt_vec {
* struct nfp_app_bpf - bpf app priv structure
* @app: backpointer to the app
*
+ * @tag_allocator: bitmap of control message tags in use
+ * @tag_alloc_next: next tag bit to allocate
+ * @tag_alloc_last: next tag bit to be freed
+ *
+ * @cmsg_replies: received cmsg replies waiting to be consumed
+ * @cmsg_wq: work queue for waiting for cmsg replies
+ *
* @map_list: list of offloaded maps
*
* @adjust_head: adjust head capability
@@ -105,6 +116,13 @@ enum pkt_vec {
struct nfp_app_bpf {
struct nfp_app *app;
+ DECLARE_BITMAP(tag_allocator, U16_MAX + 1);
+ u16 tag_alloc_next;
+ u16 tag_alloc_last;
+
+ struct sk_buff_head cmsg_replies;
+ struct wait_queue_head cmsg_wq;
+
struct list_head map_list;
struct nfp_bpf_cap_adjust_head {
@@ -284,4 +302,9 @@ nfp_bpf_goto_meta(struct nfp_prog *nfp_prog, struct
nfp_insn_meta *meta,
unsigned int insn_idx, unsigned int n_insns);
void *nfp_bpf_relo_for_vnic(struct nfp_prog *nfp_prog, struct nfp_bpf_vnic
*bv);
+
+struct sk_buff *
+nfp_bpf_cmsg_communicate(struct nfp_app_bpf *bpf, struct sk_buff *skb,
+ enum nfp_bpf_cmsg_type type, unsigned int reply_size);
+void nfp_bpf_ctrl_msg_rx(struct nfp_app *app, struct sk_buff *skb);
#endif
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_app.h
b/drivers/net/ethernet/netronome/nfp/nfp_app.h
index 32ff46a00f70..6a6eb02b516e 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_app.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_app.h
@@ -165,6 +165,7 @@ struct nfp_app {
void *priv;
};
+bool __nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb);
bool nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb);
static inline int nfp_app_init(struct nfp_app *app)
@@ -326,6 +327,14 @@ static inline int nfp_app_xdp_offload(struct nfp_app *app,
struct nfp_net *nn,
return app->type->xdp_offload(app, nn, prog);
}
+static inline bool __nfp_app_ctrl_tx(struct nfp_app *app, struct sk_buff *skb)
+{
+ trace_devlink_hwmsg(priv_to_devlink(app->pf), false, 0,
+ skb->data, skb->len);
+
+ return __nfp_ctrl_tx(app->ctrl, skb);
+}
+
static inline bool nfp_app_ctrl_tx(struct nfp_app *app, struct sk_buff *skb)
{
trace_devlink_hwmsg(priv_to_devlink(app->pf), false, 0,
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h
b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index 0e564cfabe7e..6f6e3d6fd935 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -839,6 +839,18 @@ static inline const char *nfp_net_name(struct nfp_net *nn)
return nn->dp.netdev ? nn->dp.netdev->name : "ctrl";
}
+static inline void nfp_ctrl_lock(struct nfp_net *nn)
+ __acquires(&nn->r_vecs[0].lock)
+{
+ spin_lock_bh(&nn->r_vecs[0].lock);
+}
+
+static inline void nfp_ctrl_unlock(struct nfp_net *nn)
+ __releases(&nn->r_vecs[0].lock)
+{
+ spin_unlock_bh(&nn->r_vecs[0].lock);
+}
+
/* Globals */
extern const char nfp_driver_version[];
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 07e0587dc14e..2b5cad3069a7 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1920,6 +1920,13 @@ nfp_ctrl_tx_one(struct nfp_net *nn, struct
nfp_net_r_vector *r_vec,
return false;
}
+bool __nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb)
+{
+ struct nfp_net_r_vector *r_vec = &nn->r_vecs[0];
+
+ return nfp_ctrl_tx_one(nn, r_vec, skb, false);
+}
+
bool nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb)
{
struct nfp_net_r_vector *r_vec = &nn->r_vecs[0];
--
2.15.1
