[PATCH v1 05/15] net: prepare for non devmem TCP memory providers

David Wei
2024-10-07T22:16:33Z

From: Pavel Begunkov <asml.silence@gmail.com>

There is a good bunch of places in generic paths assuming that the only
page pool memory provider is devmem TCP. As we want to reuse the net_iov
and provider infrastructure, we need to patch it up and explicitly check
the provider type when we branch into devmem TCP code.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David Wei <dw@davidwei.uk>
---
net/core/devmem.c | 4 ++--
net/core/page_pool_user.c | 15 +++++++++------
net/ipv4/tcp.c | 6 ++++++
3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/net/core/devmem.c b/net/core/devmem.c
index 83d13eb441b6..b0733cf42505 100644
--- a/net/core/devmem.c
+++ b/net/core/devmem.c
@@ -314,10 +314,10 @@ void dev_dmabuf_uninstall(struct net_device *dev)
unsigned int i;

for (i = 0; i < dev->real_num_rx_queues; i++) {
- binding = dev->_rx[i].mp_params.mp_priv;
- if (!binding)
+ if (dev->_rx[i].mp_params.mp_ops != &dmabuf_devmem_ops)
continue;

+ binding = dev->_rx[i].mp_params.mp_priv;
xa_for_each(&binding->bound_rxqs, xa_idx, rxq)
if (rxq == &dev->_rx[i]) {
xa_erase(&binding->bound_rxqs, xa_idx);
diff --git a/net/core/page_pool_user.c b/net/core/page_pool_user.c
index 48335766c1bf..0d6cb7fb562c 100644
--- a/net/core/page_pool_user.c
+++ b/net/core/page_pool_user.c
@@ -214,7 +214,7 @@ static int
page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool,
const struct genl_info *info)
{
- struct net_devmem_dmabuf_binding *binding = pool->mp_priv;
+ struct net_devmem_dmabuf_binding *binding;
size_t inflight, refsz;
void *hdr;

@@ -244,8 +244,11 @@ page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool,
pool->user.detach_time))
goto err_cancel;

- if (binding && nla_put_u32(rsp, NETDEV_A_PAGE_POOL_DMABUF, binding->id))
- goto err_cancel;
+ if (pool->mp_ops == &dmabuf_devmem_ops) {
+ binding = pool->mp_priv;
+ if (nla_put_u32(rsp, NETDEV_A_PAGE_POOL_DMABUF, binding->id))
+ goto err_cancel;
+ }

genlmsg_end(rsp, hdr);

@@ -353,16 +356,16 @@ void page_pool_unlist(struct page_pool *pool)
int page_pool_check_memory_provider(struct net_device *dev,
struct netdev_rx_queue *rxq)
{
- struct net_devmem_dmabuf_binding *binding = rxq->mp_params.mp_priv;
+ void *mp_priv = rxq->mp_params.mp_priv;
struct page_pool *pool;
struct hlist_node *n;

- if (!binding)
+ if (!mp_priv)
return 0;

mutex_lock(&page_pools_lock);
hlist_for_each_entry_safe(pool, n, &dev->page_pools, user.list) {
- if (pool->mp_priv != binding)
+ if (pool->mp_priv != mp_priv)
continue;

if (pool->slow.queue_idx == get_netdev_rx_queue_index(rxq)) {
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 5feef46426f4..2140fa1ec9f8 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -277,6 +277,7 @@
#include <net/ip.h>
#include <net/sock.h>
#include <net/rstreason.h>
+#include <net/page_pool/types.h>

#include <linux/uaccess.h>
#include <asm/ioctls.h>
@@ -2475,6 +2476,11 @@ static int tcp_recvmsg_dmabuf(struct sock *sk, const struct sk_buff *skb,
}

niov = skb_frag_net_iov(frag);
+ if (niov->pp->mp_ops != &dmabuf_devmem_ops) {
+ err = -ENODEV;
+ goto out;
+ }
+
end = start + skb_frag_size(frag);
copy = end - offset;

--
2.43.5