From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Wed, 10 Jan 2018 12:26:02 +0000
Subject: nfp: bpf: don't depend on high order allocations for program image
Patch-mainline: v4.16-rc1
Git-commit: 44a12ecc1cab7dcf4647dfef7d94f5c559c01407
References: bsc#1109837

The translator pre-allocates a buffer of maximal program size.
Due to HW/FW limitations the program buffer can't currently be
longer than 128Kb, so we used to kmalloc() it, and then map for
DMA directly.

Now that the late branch resolution is copying the program image
anyway, we can just kvmalloc() the buffer.  While at it, after
translation reallocate the buffer to save space.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/netronome/nfp/bpf/jit.c     |   16 ++++++++++++++++
 drivers/net/ethernet/netronome/nfp/bpf/offload.c |    5 +++--
 2 files changed, 19 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
@@ -2676,6 +2676,20 @@ static int nfp_bpf_ustore_calc(u64 *prog
 	return 0;
 }
 
+static void nfp_bpf_prog_trim(struct nfp_prog *nfp_prog)
+{
+	void *prog;
+
+	prog = kvmalloc_array(nfp_prog->prog_len, sizeof(u64), GFP_KERNEL);
+	if (!prog)
+		return;
+
+	nfp_prog->__prog_alloc_len = nfp_prog->prog_len * sizeof(u64);
+	memcpy(prog, nfp_prog->prog, nfp_prog->__prog_alloc_len);
+	kvfree(nfp_prog->prog);
+	nfp_prog->prog = prog;
+}
+
 int nfp_bpf_jit(struct nfp_prog *nfp_prog)
 {
 	int ret;
@@ -2691,6 +2705,8 @@ int nfp_bpf_jit(struct nfp_prog *nfp_pro
 		return -EINVAL;
 	}
 
+	nfp_bpf_prog_trim(nfp_prog);
+
 	return ret;
 }
 
--- a/drivers/net/ethernet/netronome/nfp/bpf/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/offload.c
@@ -42,6 +42,7 @@
 #include <linux/jiffies.h>
 #include <linux/timer.h>
 #include <linux/list.h>
+#include <linux/mm.h>
 
 #include <net/pkt_cls.h>
 #include <net/tc_act/tc_gact.h>
@@ -135,7 +136,7 @@ int nfp_bpf_translate(struct nfp_app *ap
 	max_instr = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN);
 	nfp_prog->__prog_alloc_len = max_instr * sizeof(u64);
 
-	nfp_prog->prog = kmalloc(nfp_prog->__prog_alloc_len, GFP_KERNEL);
+	nfp_prog->prog = kvmalloc(nfp_prog->__prog_alloc_len, GFP_KERNEL);
 	if (!nfp_prog->prog)
 		return -ENOMEM;
 
@@ -147,7 +148,7 @@ int nfp_bpf_destroy(struct nfp_app *app,
 {
 	struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv;
 
-	kfree(nfp_prog->prog);
+	kvfree(nfp_prog->prog);
 	nfp_prog_free(nfp_prog);
 
 	return 0;