nfp: bpf: allow control message sizing for map ops

In current ABI the size of the messages carrying map elements was
statically defined to at most 16 words of key and 16 words of value
(NFP word is 4 bytes).  We should not make this assumption and use
the max key and value sizes from the BPF capability instead.

To make sure old kernels don't get surprised with larger (or smaller)
messages bump the FW ABI version to 3 when key/value size is different
than 16 words.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
index 2572a4b91c7c85e067183df29d98f6a8c59e5d57..fdcd2bc98916753cc3e0275b897f938d0e8eeaf9 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
@@ -89,15 +89,32 @@ nfp_bpf_cmsg_alloc(struct nfp_app_bpf *bpf, unsigned int size)
        return skb;
 }
 
+static unsigned int
+nfp_bpf_cmsg_map_req_size(struct nfp_app_bpf *bpf, unsigned int n)
+{
+       unsigned int size;
+
+       size = sizeof(struct cmsg_req_map_op);
+       size += (bpf->cmsg_key_sz + bpf->cmsg_val_sz) * n;
+
+       return size;
+}
+
 static struct sk_buff *
 nfp_bpf_cmsg_map_req_alloc(struct nfp_app_bpf *bpf, unsigned int n)
+{
+       return nfp_bpf_cmsg_alloc(bpf, nfp_bpf_cmsg_map_req_size(bpf, n));
+}
+
+static unsigned int
+nfp_bpf_cmsg_map_reply_size(struct nfp_app_bpf *bpf, unsigned int n)
 {
        unsigned int size;
 
-       size = sizeof(struct cmsg_req_map_op);
-       size += sizeof(struct cmsg_key_value_pair) * n;
+       size = sizeof(struct cmsg_reply_map_op);
+       size += (bpf->cmsg_key_sz + bpf->cmsg_val_sz) * n;
 
-       return nfp_bpf_cmsg_alloc(bpf, size);
+       return size;
 }
 
 static u8 nfp_bpf_cmsg_get_type(struct sk_buff *skb)
@@ -338,6 +355,34 @@ void nfp_bpf_ctrl_free_map(struct nfp_app_bpf *bpf, struct nfp_bpf_map *nfp_map)
        dev_consume_skb_any(skb);
 }
 
+static void *
+nfp_bpf_ctrl_req_key(struct nfp_app_bpf *bpf, struct cmsg_req_map_op *req,
+                    unsigned int n)
+{
+       return &req->data[bpf->cmsg_key_sz * n + bpf->cmsg_val_sz * n];
+}
+
+static void *
+nfp_bpf_ctrl_req_val(struct nfp_app_bpf *bpf, struct cmsg_req_map_op *req,
+                    unsigned int n)
+{
+       return &req->data[bpf->cmsg_key_sz * (n + 1) + bpf->cmsg_val_sz * n];
+}
+
+static void *
+nfp_bpf_ctrl_reply_key(struct nfp_app_bpf *bpf, struct cmsg_reply_map_op *reply,
+                      unsigned int n)
+{
+       return &reply->data[bpf->cmsg_key_sz * n + bpf->cmsg_val_sz * n];
+}
+
+static void *
+nfp_bpf_ctrl_reply_val(struct nfp_app_bpf *bpf, struct cmsg_reply_map_op *reply,
+                      unsigned int n)
+{
+       return &reply->data[bpf->cmsg_key_sz * (n + 1) + bpf->cmsg_val_sz * n];
+}
+
 static int
 nfp_bpf_ctrl_entry_op(struct bpf_offloaded_map *offmap,
                      enum nfp_bpf_cmsg_type op,
@@ -366,12 +411,13 @@ nfp_bpf_ctrl_entry_op(struct bpf_offloaded_map *offmap,
 
        /* Copy inputs */
        if (key)
-               memcpy(&req->elem[0].key, key, map->key_size);
+               memcpy(nfp_bpf_ctrl_req_key(bpf, req, 0), key, map->key_size);
        if (value)
-               memcpy(&req->elem[0].value, value, map->value_size);
+               memcpy(nfp_bpf_ctrl_req_val(bpf, req, 0), value,
+                      map->value_size);
 
        skb = nfp_bpf_cmsg_communicate(bpf, skb, op,
-                                      sizeof(*reply) + sizeof(*reply->elem));
+                                      nfp_bpf_cmsg_map_reply_size(bpf, 1));
        if (IS_ERR(skb))
                return PTR_ERR(skb);
 
@@ -382,9 +428,11 @@ nfp_bpf_ctrl_entry_op(struct bpf_offloaded_map *offmap,
 
        /* Copy outputs */
        if (out_key)
-               memcpy(out_key, &reply->elem[0].key, map->key_size);
+               memcpy(out_key, nfp_bpf_ctrl_reply_key(bpf, reply, 0),
+                      map->key_size);
        if (out_value)
-               memcpy(out_value, &reply->elem[0].value, map->value_size);
+               memcpy(out_value, nfp_bpf_ctrl_reply_val(bpf, reply, 0),
+                      map->value_size);
 
        dev_consume_skb_any(skb);
 
@@ -428,6 +476,13 @@ int nfp_bpf_ctrl_getnext_entry(struct bpf_offloaded_map *offmap,
                                     key, NULL, 0, next_key, NULL);
 }
 
+unsigned int nfp_bpf_ctrl_cmsg_mtu(struct nfp_app_bpf *bpf)
+{
+       return max3((unsigned int)NFP_NET_DEFAULT_MTU,
+                   nfp_bpf_cmsg_map_req_size(bpf, 1),
+                   nfp_bpf_cmsg_map_reply_size(bpf, 1));
+}
+
 void nfp_bpf_ctrl_msg_rx(struct nfp_app *app, struct sk_buff *skb)
 {
        struct nfp_app_bpf *bpf = app->priv;

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/fw.h b/drivers/net/ethernet/netronome/nfp/bpf/fw.h
index 58bad868bb6fa9c837256bf90b7746d39c3904a0..813644e90b2751292e81f6ac23bc0d847a20624d 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/bpf/fw.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/fw.h
@@ -99,6 +99,7 @@ enum nfp_bpf_cmsg_type {
 #define CMSG_TYPE_MAP_REPLY_BIT                7
 #define __CMSG_REPLY(req)              (BIT(CMSG_TYPE_MAP_REPLY_BIT) | (req))
 
+/* BPF ABIv2 fixed-length control message fields */
 #define CMSG_MAP_KEY_LW                        16
 #define CMSG_MAP_VALUE_LW              16
 
@@ -148,24 +149,19 @@ struct cmsg_reply_map_free_tbl {
        __be32 count;
 };
 
-struct cmsg_key_value_pair {
-       __be32 key[CMSG_MAP_KEY_LW];
-       __be32 value[CMSG_MAP_VALUE_LW];
-};
-
 struct cmsg_req_map_op {
        struct cmsg_hdr hdr;
        __be32 tid;
        __be32 count;
        __be32 flags;
-       struct cmsg_key_value_pair elem[0];
+       u8 data[0];
 };
 
 struct cmsg_reply_map_op {
        struct cmsg_reply_map_simple reply_hdr;
        __be32 count;
        __be32 resv;
-       struct cmsg_key_value_pair elem[0];
+       u8 data[0];
 };
 
 struct cmsg_bpf_event {

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.c b/drivers/net/ethernet/netronome/nfp/bpf/main.c
index 1f79246765d1a03f955952a2fe5a9d3c4ad1ab16..d9d37aa860e0c9aa0b89e464c5cac3c9bfa63a67 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.c
@@ -356,7 +356,7 @@ nfp_bpf_parse_cap_abi_version(struct nfp_app_bpf *bpf, void __iomem *value,
        }
 
        bpf->abi_version = readl(value);
-       if (bpf->abi_version != 2) {
+       if (bpf->abi_version < 2 || bpf->abi_version > 3) {
                nfp_warn(bpf->app->cpp, "unsupported BPF ABI version: %d\n",
                         bpf->abi_version);
                bpf->abi_version = 0;
@@ -486,6 +486,15 @@ static int nfp_bpf_init(struct nfp_app *app)
        if (err)
                goto err_free_neutral_maps;
 
+       if (bpf->abi_version < 3) {
+               bpf->cmsg_key_sz = CMSG_MAP_KEY_LW * 4;
+               bpf->cmsg_val_sz = CMSG_MAP_VALUE_LW * 4;
+       } else {
+               bpf->cmsg_key_sz = bpf->maps.max_key_sz;
+               bpf->cmsg_val_sz = bpf->maps.max_val_sz;
+               app->ctrl_mtu = nfp_bpf_ctrl_cmsg_mtu(bpf);
+       }
+
        bpf->bpf_dev = bpf_offload_dev_create();
        err = PTR_ERR_OR_ZERO(bpf->bpf_dev);
        if (err)

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h
index 62cdb183efdb9544056a61848ae97e694d75f488..792ebc4081a3763bbd300eff8e69257c731d2ada 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h
@@ -121,6 +121,9 @@ enum pkt_vec {
  * @cmsg_replies:      received cmsg replies waiting to be consumed
  * @cmsg_wq:           work queue for waiting for cmsg replies
  *
+ * @cmsg_key_sz:       size of key in cmsg element array
+ * @cmsg_val_sz:       size of value in cmsg element array
+ *
  * @map_list:          list of offloaded maps
  * @maps_in_use:       number of currently offloaded maps
  * @map_elems_in_use:  number of elements allocated to offloaded maps
@@ -166,6 +169,9 @@ struct nfp_app_bpf {
        struct sk_buff_head cmsg_replies;
        struct wait_queue_head cmsg_wq;
 
+       unsigned int cmsg_key_sz;
+       unsigned int cmsg_val_sz;
+
        struct list_head map_list;
        unsigned int maps_in_use;
        unsigned int map_elems_in_use;
@@ -496,6 +502,7 @@ nfp_bpf_goto_meta(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 
 void *nfp_bpf_relo_for_vnic(struct nfp_prog *nfp_prog, struct nfp_bpf_vnic *bv);
 
+unsigned int nfp_bpf_ctrl_cmsg_mtu(struct nfp_app_bpf *bpf);
 long long int
 nfp_bpf_ctrl_alloc_map(struct nfp_app_bpf *bpf, struct bpf_map *map);
 void

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
index 44d3ea75d043a2867fa6ae717535fae80c6a4dd6..4c6fb9ecb72c22ffeefa2d3c2bde32bbe68004a9 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
@@ -264,7 +264,6 @@
  * %NFP_NET_CFG_BPF_ADDR:      DMA address of the buffer with JITed BPF code
  */
 #define NFP_NET_CFG_BPF_ABI            0x0080
-#define   NFP_NET_BPF_ABI              2
 #define NFP_NET_CFG_BPF_CAP            0x0081
 #define   NFP_NET_BPF_CAP_RELO         (1 << 0) /* seamless reload */
 #define NFP_NET_CFG_BPF_MAX_LEN                0x0082