[PATCH v14 084/138] mm/page_alloc: Add folio allocation functions

Matthew Wilcox (Oracle)
2021-07-15T04:45:47Z

The __folio_alloc(), __folio_alloc_node() and folio_alloc() functions
are mostly for type safety, but they also ensure that the page allocator
allocates a compound page and initialises the deferred list if the page
is large enough to have one.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
include/linux/gfp.h | 16 ++++++++++++++++
mm/mempolicy.c | 10 ++++++++++
mm/page_alloc.c | 12 ++++++++++++
3 files changed, 38 insertions(+)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index dc5ff40608ce..3745efd21cf6 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -523,6 +523,8 @@ static inline void arch_alloc_page(struct page *page, int order) { }

struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid,
nodemask_t *nodemask);
+struct folio *__folio_alloc(gfp_t gfp, unsigned int order, int preferred_nid,
+ nodemask_t *nodemask);

unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
nodemask_t *nodemask, int nr_pages,
@@ -564,6 +566,15 @@ __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
return __alloc_pages(gfp_mask, order, nid, NULL);
}

+static inline
+struct folio *__folio_alloc_node(gfp_t gfp, unsigned int order, int nid)
+{
+ VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
+ VM_WARN_ON((gfp & __GFP_THISNODE) && !node_online(nid));
+
+ return __folio_alloc(gfp, order, nid, NULL);
+}
+
/*
* Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
* prefer the current CPU's closest node. Otherwise node must be valid and
@@ -580,6 +591,7 @@ static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,

#ifdef CONFIG_NUMA
struct page *alloc_pages(gfp_t gfp, unsigned int order);
+struct folio *folio_alloc(gfp_t gfp, unsigned order);
extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
struct vm_area_struct *vma, unsigned long addr,
int node, bool hugepage);
@@ -590,6 +602,10 @@ static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order)
{
return alloc_pages_node(numa_node_id(), gfp_mask, order);
}
+static inline struct folio *folio_alloc(gfp_t gfp, unsigned int order)
+{
+ return __folio_alloc_node(gfp, order, numa_node_id());
+}
#define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
alloc_pages(gfp_mask, order)
#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index e32360e90274..95d0cf05f7ca 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2249,6 +2249,16 @@ struct page *alloc_pages(gfp_t gfp, unsigned order)
}
EXPORT_SYMBOL(alloc_pages);

+struct folio *folio_alloc(gfp_t gfp, unsigned order)
+{
+ struct page *page = alloc_pages(gfp | __GFP_COMP, order);
+
+ if (page && order > 1)
+ prep_transhuge_page(page);
+ return (struct folio *)page;
+}
+EXPORT_SYMBOL(folio_alloc);
+
int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
{
struct mempolicy *pol = mpol_dup(vma_policy(src));
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d72a0d9d4184..d03145671934 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5399,6 +5399,18 @@ struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid,
}
EXPORT_SYMBOL(__alloc_pages);

+struct folio *__folio_alloc(gfp_t gfp, unsigned int order, int preferred_nid,
+ nodemask_t *nodemask)
+{
+ struct page *page = __alloc_pages(gfp | __GFP_COMP, order,
+ preferred_nid, nodemask);
+
+ if (page && order > 1)
+ prep_transhuge_page(page);
+ return (struct folio *)page;
+}
+EXPORT_SYMBOL(__folio_alloc);
+
/*
* Common helper functions. Never use with __GFP_HIGHMEM because the returned
* address cannot represent highmem pages. Use alloc_pages and then kmap if
--
2.30.2