On 6/13/24 02:35, Mina Almasry wrote:
Abstrace the memory type from the page_pool so we can later add support for new memory types. Convert the page_pool to use the new netmem type abstraction, rather than use struct page directly.
As of this patch the netmem type is a no-op abstraction: it's always a struct page underneath. All the page pool internals are converted to use struct netmem instead of struct page, and the page pool now exports 2 APIs:
- The existing struct page API.
- The new struct netmem API.
nits below,
Reviewed-by: Pavel Begunkov asml.silence@gmail.com
Keeping the existing API is transitional; we do not want to refactor all the current drivers using the page pool at once.
The netmem abstraction is currently a no-op. The page_pool uses page_to_netmem() to convert allocated pages to netmem, and uses netmem_to_page() to convert the netmem back to pages to pass to mm APIs,
Follow up patches to this series add non-paged netmem support to the page_pool. This change is factored out on its own to limit the code churn to this 1 patch, for ease of code review.
Signed-off-by: Mina Almasry almasrymina@google.com #endif /* _NET_NETMEM_H */ diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h index 873631c79ab16..5e129d5304f53 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -55,6 +55,8 @@ #include <linux/dma-mapping.h> #include <net/page_pool/types.h> +#include <net/net_debug.h> +#include <net/netmem.h> #ifdef CONFIG_PAGE_POOL_STATS /* Deprecated driver-facing API, use netlink instead */ @@ -103,7 +105,7 @@ static inline struct page *page_pool_dev_alloc_pages(struct page_pool *pool)
- Get a page fragment from the page allocator or page_pool caches.
- Return:
- Return allocated page fragment, otherwise return NULL.
- Return allocated page fragment, otherwise return 0.
It's a page_pool_dev_alloc_frag()'s comment, and the function still returns a pointer.
...
static inline void *page_pool_alloc_va(struct page_pool *pool, @@ -172,7 +174,8 @@ static inline void *page_pool_alloc_va(struct page_pool *pool, struct page *page; /* Mask off __GFP_HIGHMEM to ensure we can use page_address() */
- page = page_pool_alloc(pool, &offset, size, gfp & ~__GFP_HIGHMEM);
- page = netmem_to_page(
page_pool_alloc(pool, &offset, size, gfp & ~__GFP_HIGHMEM));@@ -189,7 +192,7 @@ static inline void *page_pool_alloc_va(struct page_pool *pool,
- it returns va of the allocated page or page fragment.
- Return:
- Return the va for the allocated page or page fragment, otherwise return NULL.
- Return the va for the allocated page or page fragment, otherwise return 0.
ditto
*/ static inline void *page_pool_dev_alloc_va(struct page_pool *pool, unsigned int *size) @@ -212,6 +215,11 @@ page_pool_get_dma_dir(const struct page_pool *pool) return pool->p.dma_dir; } +static inline void page_pool_fragment_netmem(netmem_ref netmem, long nr) +{
- atomic_long_set(&netmem_to_page(netmem)->pp_ref_count, nr);
+}
...