xsk: add multi-buffer support for sockets sharing umem

Userspace applications indicate their multi-buffer capability to xsk
using XSK_USE_SG socket bind flag. For sockets using shared umem the
bind flag may contain XSK_USE_SG only for the first socket. For any
subsequent socket the only option supported is XDP_SHARED_UMEM.

Add option XDP_UMEM_SG_FLAG in umem config flags to store the
multi-buffer handling capability when indicated by XSK_USE_SG option in
bing flag by the first socket. Use this to derive multi-buffer capability
for subsequent sockets in xsk core.

Signed-off-by: Tirthendu Sarkar <tirthendu.sarkar@intel.com>
Fixes: 81470b5c3c ("xsk: introduce XSK_USE_SG bind flag for xsk socket")
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230907035032.2627879-1-tirthendu.sarkar@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Tirthendu Sarkar 2023-09-07 09:20:32 +05:30 committed by Alexei Starovoitov
parent 5c04433daf
commit d609f3d228
3 changed files with 6 additions and 1 deletions

View File

@ -14,6 +14,8 @@
#include <linux/mm.h>
#include <net/sock.h>
#define XDP_UMEM_SG_FLAG (1 << 1)
struct net_device;
struct xsk_queue;
struct xdp_buff;

View File

@ -1228,7 +1228,7 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
xs->dev = dev;
xs->zc = xs->umem->zc;
xs->sg = !!(flags & XDP_USE_SG);
xs->sg = !!(xs->umem->flags & XDP_UMEM_SG_FLAG);
xs->queue_id = qid;
xp_add_xsk(xs->pool, xs);

View File

@ -170,6 +170,9 @@ int xp_assign_dev(struct xsk_buff_pool *pool,
if (err)
return err;
if (flags & XDP_USE_SG)
pool->umem->flags |= XDP_UMEM_SG_FLAG;
if (flags & XDP_USE_NEED_WAKEUP)
pool->uses_need_wakeup = true;
/* Tx needs to be explicitly woken up the first time. Also