nfp: bpf: implement helpers for FW map ops

Implement calls for FW map communication.

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

3 files changed, 288 insertions, 4 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
index 46753ee9f7c5..71e6586acc36 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
@@ -31,6 +31,7 @@
  * SOFTWARE.
  */
 
+#include <linux/bpf.h>
 #include <linux/bitops.h>
 #include <linux/bug.h>
 #include <linux/jiffies.h>
@@ -79,6 +80,28 @@ static void nfp_bpf_free_tag(struct nfp_app_bpf *bpf, u16 tag)
                 bpf->tag_alloc_last++;
 }
 
+static struct sk_buff *
+nfp_bpf_cmsg_alloc(struct nfp_app_bpf *bpf, unsigned int size)
+{
+        struct sk_buff *skb;
+
+        skb = nfp_app_ctrl_msg_alloc(bpf->app, size, GFP_KERNEL);
+        skb_put(skb, size);
+
+        return skb;
+}
+
+static struct sk_buff *
+nfp_bpf_cmsg_map_req_alloc(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;
+
+        return nfp_bpf_cmsg_alloc(bpf, size);
+}
+
 static unsigned int nfp_bpf_cmsg_get_tag(struct sk_buff *skb)
 {
         struct cmsg_hdr *hdr;
@@ -159,7 +182,7 @@ nfp_bpf_cmsg_wait_reply(struct nfp_app_bpf *bpf, enum nfp_bpf_cmsg_type type,
         return skb;
 }
 
-struct sk_buff *
+static 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)
 {
@@ -206,6 +229,191 @@ err_free:
         return ERR_PTR(-EIO);
 }
 
+static int
+nfp_bpf_ctrl_rc_to_errno(struct nfp_app_bpf *bpf,
+                         struct cmsg_reply_map_simple *reply)
+{
+        static const int res_table[] = {
+                [CMSG_RC_SUCCESS]       = 0,
+                [CMSG_RC_ERR_MAP_FD]    = -EBADFD,
+                [CMSG_RC_ERR_MAP_NOENT] = -ENOENT,
+                [CMSG_RC_ERR_MAP_ERR]   = -EINVAL,
+                [CMSG_RC_ERR_MAP_PARSE] = -EIO,
+                [CMSG_RC_ERR_MAP_EXIST] = -EEXIST,
+                [CMSG_RC_ERR_MAP_NOMEM] = -ENOMEM,
+                [CMSG_RC_ERR_MAP_E2BIG] = -E2BIG,
+        };
+        u32 rc;
+
+        rc = be32_to_cpu(reply->rc);
+        if (rc >= ARRAY_SIZE(res_table)) {
+                cmsg_warn(bpf, "FW responded with invalid status: %u\n", rc);
+                return -EIO;
+        }
+
+        return res_table[rc];
+}
+
+long long int
+nfp_bpf_ctrl_alloc_map(struct nfp_app_bpf *bpf, struct bpf_map *map)
+{
+        struct cmsg_reply_map_alloc_tbl *reply;
+        struct cmsg_req_map_alloc_tbl *req;
+        struct sk_buff *skb;
+        u32 tid;
+        int err;
+
+        skb = nfp_bpf_cmsg_alloc(bpf, sizeof(*req));
+        if (!skb)
+                return -ENOMEM;
+
+        req = (void *)skb->data;
+        req->key_size = cpu_to_be32(map->key_size);
+        req->value_size = cpu_to_be32(map->value_size);
+        req->max_entries = cpu_to_be32(map->max_entries);
+        req->map_type = cpu_to_be32(map->map_type);
+        req->map_flags = 0;
+
+        skb = nfp_bpf_cmsg_communicate(bpf, skb, CMSG_TYPE_MAP_ALLOC,
+                                       sizeof(*reply));
+        if (IS_ERR(skb))
+                return PTR_ERR(skb);
+
+        reply = (void *)skb->data;
+        err = nfp_bpf_ctrl_rc_to_errno(bpf, &reply->reply_hdr);
+        if (err)
+                goto err_free;
+
+        tid = be32_to_cpu(reply->tid);
+        dev_consume_skb_any(skb);
+
+        return tid;
+err_free:
+        dev_kfree_skb_any(skb);
+        return err;
+}
+
+void nfp_bpf_ctrl_free_map(struct nfp_app_bpf *bpf, struct nfp_bpf_map *nfp_map)
+{
+        struct cmsg_reply_map_free_tbl *reply;
+        struct cmsg_req_map_free_tbl *req;
+        struct sk_buff *skb;
+        int err;
+
+        skb = nfp_bpf_cmsg_alloc(bpf, sizeof(*req));
+        if (!skb) {
+                cmsg_warn(bpf, "leaking map - failed to allocate msg\n");
+                return;
+        }
+
+        req = (void *)skb->data;
+        req->tid = cpu_to_be32(nfp_map->tid);
+
+        skb = nfp_bpf_cmsg_communicate(bpf, skb, CMSG_TYPE_MAP_FREE,
+                                       sizeof(*reply));
+        if (IS_ERR(skb)) {
+                cmsg_warn(bpf, "leaking map - I/O error\n");
+                return;
+        }
+
+        reply = (void *)skb->data;
+        err = nfp_bpf_ctrl_rc_to_errno(bpf, &reply->reply_hdr);
+        if (err)
+                cmsg_warn(bpf, "leaking map - FW responded with: %d\n", err);
+
+        dev_consume_skb_any(skb);
+}
+
+static int
+nfp_bpf_ctrl_entry_op(struct bpf_offloaded_map *offmap,
+                      enum nfp_bpf_cmsg_type op,
+                      u8 *key, u8 *value, u64 flags, u8 *out_key, u8 *out_value)
+{
+        struct nfp_bpf_map *nfp_map = offmap->dev_priv;
+        struct nfp_app_bpf *bpf = nfp_map->bpf;
+        struct bpf_map *map = &offmap->map;
+        struct cmsg_reply_map_op *reply;
+        struct cmsg_req_map_op *req;
+        struct sk_buff *skb;
+        int err;
+
+        /* FW messages have no space for more than 32 bits of flags */
+        if (flags >> 32)
+                return -EOPNOTSUPP;
+
+        skb = nfp_bpf_cmsg_map_req_alloc(bpf, 1);
+        if (!skb)
+                return -ENOMEM;
+
+        req = (void *)skb->data;
+        req->tid = cpu_to_be32(nfp_map->tid);
+        req->count = cpu_to_be32(1);
+        req->flags = cpu_to_be32(flags);
+
+        /* Copy inputs */
+        if (key)
+                memcpy(&req->elem[0].key, key, map->key_size);
+        if (value)
+                memcpy(&req->elem[0].value, value, map->value_size);
+
+        skb = nfp_bpf_cmsg_communicate(bpf, skb, op,
+                                       sizeof(*reply) + sizeof(*reply->elem));
+        if (IS_ERR(skb))
+                return PTR_ERR(skb);
+
+        reply = (void *)skb->data;
+        err = nfp_bpf_ctrl_rc_to_errno(bpf, &reply->reply_hdr);
+        if (err)
+                goto err_free;
+