[PATCH 02/24] netmem: Add utility functions
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Date: 2022-11-30 22:08:35
Also in:
linux-mm
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
netmem_page() is defined this way to preserve constness. page_netmem() doesn't call compound_head() because netmem users always use the head page; it does include a debugging assert to check that it's true. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- include/net/page_pool.h | 42 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+)
diff --git a/include/net/page_pool.h b/include/net/page_pool.h
index af6ff8c302a0..0ce20b95290b 100644
--- a/include/net/page_pool.h
+++ b/include/net/page_pool.h@@ -91,6 +91,48 @@ NETMEM_MATCH(_refcount, _refcount); #undef NETMEM_MATCH static_assert(sizeof(struct netmem) <= sizeof(struct page)); +#define netmem_page(nmem) (_Generic((*nmem), \ + const struct netmem: (const struct page *)nmem, \ + struct netmem: (struct page *)nmem)) + +static inline struct netmem *page_netmem(struct page *page) +{ + VM_BUG_ON_PAGE(PageTail(page), page); + return (struct netmem *)page; +} + +static inline unsigned long netmem_pfn(const struct netmem *nmem) +{ + return page_to_pfn(netmem_page(nmem)); +} + +static inline unsigned long netmem_nid(const struct netmem *nmem) +{ + return page_to_nid(netmem_page(nmem)); +} + +static inline struct netmem *virt_to_netmem(const void *x) +{ + return page_netmem(virt_to_head_page(x)); +} + +static inline int netmem_ref_count(const struct netmem *nmem) +{ + return page_ref_count(netmem_page(nmem)); +} + +static inline void netmem_put(struct netmem *nmem) +{ + struct folio *folio = (struct folio *)nmem; + + return folio_put(folio); +} + +static inline bool netmem_is_pfmemalloc(const struct netmem *nmem) +{ + return nmem->pp_magic & BIT(1); +} + /* * Fast allocation side cache array/stack *
--
2.35.1