[PATCH net-next v7 1/9] netmem: add niov->type attribute to distinguish different net_iov types

Mina Almasry
2025-03-08T21:40:49Z

Later patches in the series adds TX net_iovs where there is no pp
associated, so we can't rely on niov->pp->mp_ops to tell what is the
type of the net_iov.

Add a type enum to the net_iov which tells us the net_iov type.

Signed-off-by: Mina Almasry <almasrymina@google.com>

---

v7:
- New patch

---
include/net/netmem.h | 15 ++++++++++++++-
net/core/devmem.c | 3 ++-
2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/include/net/netmem.h b/include/net/netmem.h
index c61d5b21e7b4..16ef53ea713a 100644
--- a/include/net/netmem.h
+++ b/include/net/netmem.h
@@ -20,8 +20,21 @@ DECLARE_STATIC_KEY_FALSE(page_pool_mem_providers);
*/
#define NET_IOV 0x01UL

+enum net_iov_type {
+ /* The unspecified type is temporary until the io_uring net_iovs being
+ * worked on in parallel are migrated to specify their type, then this
+ * can be deprecated.
+ */
+ NET_IOV_UNSPECIFIED = 0,
+ NET_IOV_DMABUF,
+
+ /* Force size to unsigned long to make the NET_IOV_ASSERTS below pass.
+ */
+ NET_IOV_MAX = ULONG_MAX,
+};
+
struct net_iov {
- unsigned long __unused_padding;
+ enum net_iov_type type;
unsigned long pp_magic;
struct page_pool *pp;
struct net_iov_area *owner;
diff --git a/net/core/devmem.c b/net/core/devmem.c
index 7c6e0b5b6acb..69c160ad3ebd 100644
--- a/net/core/devmem.c
+++ b/net/core/devmem.c
@@ -32,7 +32,7 @@ static const struct memory_provider_ops dmabuf_devmem_ops;

bool net_is_devmem_iov(struct net_iov *niov)
{
- return niov->pp->mp_ops == &dmabuf_devmem_ops;
+ return niov->type == NET_IOV_DMABUF;
}

static void net_devmem_dmabuf_free_chunk_owner(struct gen_pool *genpool,
@@ -297,6 +297,7 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd,

for (i = 0; i < owner->area.num_niovs; i++) {
niov = &owner->area.niovs[i];
+ niov->type = NET_IOV_DMABUF;
niov->owner = &owner->area;
page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov),
net_devmem_get_dma_addr(niov));
--
2.49.0.rc0.332.g42c0ae87b1-goog