nfp: bpf: relocate jump targets just before the load

Don't translate the program assuming it will be loaded at a given
address.  This will be required for sharing programs between ports
of the same NIC, tail calls and subprograms.  It will also make the
jump targets easier to understand when dumping the program to user
space.

Translate the program as if it was going to be loaded at address
zero.  When load happens add the load offset in and set addresses
of special branches.

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

1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/offload.c b/drivers/net/ethernet/netronome/nfp/bpf/offload.c
index 0ca6faaacc58..5f165e1d7648 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/offload.c
@@ -130,10 +130,7 @@ int nfp_bpf_translate(struct nfp_app *app, struct nfp_net *nn,
 			prog->aux->stack_depth, stack_size);
 		return -EOPNOTSUPP;
 	}
-
 	nfp_prog->stack_depth = round_up(prog->aux->stack_depth, 4);
-	nfp_prog->start_off = nn_readw(nn, NFP_NET_CFG_BPF_START);
-	nfp_prog->tgt_done = nn_readw(nn, NFP_NET_CFG_BPF_DONE);
 
 	max_instr = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN);
 	nfp_prog->__prog_alloc_len = max_instr * sizeof(u64);
@@ -161,6 +158,7 @@ static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
 	struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv;
 	unsigned int max_mtu;
 	dma_addr_t dma_addr;
+	void *img;
 	int err;
 
 	max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
@@ -169,11 +167,17 @@ static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
 		return -EOPNOTSUPP;
 	}
 
-	dma_addr = dma_map_single(nn->dp.dev, nfp_prog->prog,
+	img = nfp_bpf_relo_for_vnic(nfp_prog, nn->app_priv);
+	if (IS_ERR(img))
+		return PTR_ERR(img);
+
+	dma_addr = dma_map_single(nn->dp.dev, img,
 				  nfp_prog->prog_len * sizeof(u64),
 				  DMA_TO_DEVICE);
-	if (dma_mapping_error(nn->dp.dev, dma_addr))
+	if (dma_mapping_error(nn->dp.dev, dma_addr)) {
+		kfree(img);
 		return -ENOMEM;
+	}
 
 	nn_writew(nn, NFP_NET_CFG_BPF_SIZE, nfp_prog->prog_len);
 	nn_writeq(nn, NFP_NET_CFG_BPF_ADDR, dma_addr);
@@ -185,6 +189,7 @@ static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
 
 	dma_unmap_single(nn->dp.dev, dma_addr, nfp_prog->prog_len * sizeof(u64),
 			 DMA_TO_DEVICE);
+	kfree(img);
 
 	return err;
 }