github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-13 15:40:03 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

xsk: honor XDP_TX_METADATA in zero-copy path

Browse Source 
The zero-copy path reads TX metadata whenever the UMEM has metadata space,
even if the descriptor does not set XDP_TX_METADATA. Pass descriptor
options through the metadata helpers and ignore metadata unless the option
is set.

This does not fix the existing per-WQE metadata handling for mlx5 MPWQEs.
Only the descriptor that starts a session passes through
xsk_tx_metadata_request() and configures offload state shared by the batch.
Metadata on descriptors joining an open session is therefore not validated
and does not configure its requested offloads. In addition, a non-NULL
metadata pointer from such a descriptor is treated as a timestamp
completion request even when XDP_TXMD_FLAGS_TIMESTAMP is not set, so its
metadata union can be overwritten with an unrequested timestamp. Fixing
mixed metadata states within one MPWQE requires a separate change.

Fixes: 48eb03dd26 ("xsk: Add TX timestamp and TX checksum offload support")
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Link: https://patch.msgid.link/20260819160535.1472459-3-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Stanislav Fomichev 2026-08-19 09:05:34 -07:00 committed by Jakub Kicinski
parent bd7d30bd1d
commit a6e4b9a6de
7 changed files with 26 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/net/ethernet/intel/igc/igc_main.c
View File

@ -3071,7 +3071,8 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
olinfo_status = xdp_desc.len << IGC_ADVTXD_PAYLEN_SHIFT;
dma = xsk_buff_raw_get_dma(pool, xdp_desc.addr);
meta = xsk_buff_get_metadata(pool, xdp_desc.addr);
meta = xsk_buff_get_metadata(pool, xdp_desc.addr,
xdp_desc.options);
xsk_buff_raw_dma_sync_for_device(pool, dma, xdp_desc.len);
bi = &ring->tx_buffer_info[ntu];

2
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
View File

@ -99,7 +99,7 @@ bool mlx5e_xsk_tx(struct mlx5e_xdpsq *sq, unsigned int budget)
xdptxd.dma_addr = xsk_buff_raw_get_dma(pool, desc.addr);
xdptxd.data = xsk_buff_raw_get_data(pool, desc.addr);
xdptxd.len = desc.len;
meta = xsk_buff_get_metadata(pool, desc.addr);
meta = xsk_buff_get_metadata(pool, desc.addr, desc.options);
xsk_buff_raw_dma_sync_for_device(pool, xdptxd.dma_addr, xdptxd.len);

3
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
View File

@ -2723,7 +2723,8 @@ static bool stmmac_xdp_xmit_zc(struct stmmac_priv *priv, u32 queue, u32 budget)
tx_desc = stmmac_get_tx_desc(priv, tx_q, entry);
dma_addr = xsk_buff_raw_get_dma(pool, xdp_desc.addr);
meta = xsk_buff_get_metadata(pool, xdp_desc.addr);
meta = xsk_buff_get_metadata(pool, xdp_desc.addr,
xdp_desc.options);
xsk_buff_raw_dma_sync_for_device(pool, dma_addr, xdp_desc.len);
/* To return XDP buffer to XSK pool, we simple call

2
include/net/libeth/xsk.h
View File

@ -196,7 +196,7 @@ __libeth_xsk_xmit_fill_buf_md(const struct xdp_desc *xdesc,
struct libeth_xdp_tx_desc desc;
struct xdp_desc_ctx ctx;
ctx = xsk_buff_raw_get_ctx(sq->pool, xdesc->addr);
ctx = xsk_buff_raw_get_ctx(sq->pool, xdesc->addr, xdesc->options);
desc = (typeof(desc)){
.addr = ctx.dma,
__libeth_xdp_tx_len(xdesc->len),

22
include/net/xdp_sock_drv.h
View File

@ -240,6 +240,7 @@ static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
* xsk_buff_raw_get_ctx - get &xdp_desc context
* @pool: XSk buff pool desc address belongs to
* @addr: desc address (from userspace)
* @options: desc options (from userspace)
*
* Wrapper for xp_raw_get_ctx() to be used in drivers, see its kdoc for
* details.
@ -248,9 +249,9 @@ static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
* pointer, if it is present (initialized to %NULL otherwise).
*/
static inline struct xdp_desc_ctx
xsk_buff_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr)
xsk_buff_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr, u32 options)
{
return xp_raw_get_ctx(pool, addr);
return xp_raw_get_ctx(pool, addr, options);
}
#define XDP_TXMD_FLAGS_VALID ( \
@ -318,18 +319,20 @@ xsk_tx_metadata_request(const struct xsk_buff_pool *pool,
}
static inline struct xsk_tx_metadata *
__xsk_buff_get_metadata(const struct xsk_buff_pool *pool, void *data)
__xsk_buff_get_metadata(const struct xsk_buff_pool *pool, void *data,
unsigned int options)
{
if (!pool->tx_metadata_len)
if (!pool->tx_metadata_len || !(options & XDP_TX_METADATA))
return NULL;
return data - pool->tx_metadata_len;
}
static inline struct xsk_tx_metadata *
xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr)
xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr, u32 options)
{
return __xsk_buff_get_metadata(pool, xp_raw_get_data(pool, addr));
return __xsk_buff_get_metadata(pool, xp_raw_get_data(pool, addr),
options);
}
static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp)
@ -510,7 +513,7 @@ static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
}
static inline struct xdp_desc_ctx
xsk_buff_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr)
xsk_buff_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr, u32 options)
{
return (struct xdp_desc_ctx){ };
}
@ -530,13 +533,14 @@ xsk_tx_metadata_request(const struct xsk_buff_pool *pool,
}
static inline struct xsk_tx_metadata *
__xsk_buff_get_metadata(const struct xsk_buff_pool *pool, void *data)
__xsk_buff_get_metadata(const struct xsk_buff_pool *pool, void *data,
unsigned int options)
{
return NULL;
}
static inline struct xsk_tx_metadata *
xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr)
xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr, u32 options)
{
return NULL;
}

3
include/net/xsk_buff_pool.h
View File

@ -154,7 +154,8 @@ struct xdp_desc_ctx {
struct xsk_tx_metadata *meta;
};
struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr);
struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr,
u32 options);
static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb)
{

7
net/xdp/xsk_buff_pool.c
View File

@ -763,6 +763,7 @@ EXPORT_SYMBOL(xp_raw_get_dma);
* xp_raw_get_ctx - get &xdp_desc context
* @pool: XSk buff pool desc address belongs to
* @addr: desc address (from userspace)
* @options: desc options (from userspace)
*
* Helper for getting desc's DMA address and metadata pointer, if present.
* Saves one call on hotpath and double calculation of the actual address.
@ -771,14 +772,16 @@ EXPORT_SYMBOL(xp_raw_get_dma);
* Return: new &xdp_desc_ctx struct containing desc's DMA address and metadata
* pointer, if it is present (initialized to %NULL otherwise).
*/
struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr)
struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr,
u32 options)
{
struct xdp_desc_ctx ret;
addr = __xp_raw_get_addr(pool, addr);
ret.dma = __xp_raw_get_dma(pool, addr);
ret.meta = __xsk_buff_get_metadata(pool, __xp_raw_get_data(pool, addr));
ret.meta = __xsk_buff_get_metadata(pool, __xp_raw_get_data(pool, addr),
options);
return ret;
}