From 1b725b0c8163cfd2d9ab22057df46b487981cfea Mon Sep 17 00:00:00 2001
From: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Date: Wed, 19 Jul 2023 15:24:04 +0200
Subject: [PATCH] xsk: allow core/drivers to test EOP bit
Drivers are used to check for EOP bit whereas AF_XDP operates on
inverted logic - user space indicates that current frag is not the last
one and packet continues. For AF_XDP core needs, add xp_mb_desc() that
will simply test XDP_PKT_CONTD from xdp_desc::options, but in order to
preserve drivers default behavior, introduce an interface for ZC drivers
that will negate xp_mb_desc() result and therefore make it easier to
test EOP bit from during production of HW Tx descriptors.
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230719132421.584801-8-maciej.fijalkowski@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
include/net/xdp_sock_drv.h | 10 ++++++++++
include/net/xsk_buff_pool.h | 5 +++++
2 files changed, 15 insertions(+)
diff --git a/include/net/xdp_sock_drv.h b/include/net/xdp_sock_drv.h
index c243f906ebed4..0d34cdb5567d4 100644
--- a/include/net/xdp_sock_drv.h
+++ b/include/net/xdp_sock_drv.h
@@ -89,6 +89,11 @@ static inline struct xdp_buff *xsk_buff_alloc(struct xsk_buff_pool *pool)
return xp_alloc(pool);
}
+static inline bool xsk_is_eop_desc(struct xdp_desc *desc)
+{
+ return !xp_mb_desc(desc);
+}
+
/* Returns as many entries as possible up to max. 0 <= N <= max. */
static inline u32 xsk_buff_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
{
@@ -241,6 +246,11 @@ static inline struct xdp_buff *xsk_buff_alloc(struct xsk_buff_pool *pool)
return NULL;
}
+static inline bool xsk_is_eop_desc(struct xdp_desc *desc)
+{
+ return false;
+}
+
static inline u32 xsk_buff_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
{
return 0;
diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h
index a8d7b8a3688a6..4dcca163e076e 100644
--- a/include/net/xsk_buff_pool.h
+++ b/include/net/xsk_buff_pool.h
@@ -184,6 +184,11 @@ static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool,
!(pool->dma_pages[addr >> PAGE_SHIFT] & XSK_NEXT_PG_CONTIG_MASK);
}
+static inline bool xp_mb_desc(struct xdp_desc *desc)
+{
+ return desc->options & XDP_PKT_CONTD;
+}
+
static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr)
{
return addr & pool->chunk_mask;
--
2.30.2