The patch titled
Subject: mm/cma: add cma_{alloc,free}_folio()
has been added to the -mm mm-unstable branch. Its filename is
mm-cma-add-cma_allocfree_folio.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-cma-add-cma_allocfree_folio.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Yu Zhao <yuzhao@xxxxxxxxxx>
Subject: mm/cma: add cma_{alloc,free}_folio()
Date: Tue, 13 Aug 2024 21:54:50 -0600
With alloc_contig_range() and free_contig_range() supporting large folios,
CMA can allocate and free large folios too, by cma_alloc_folio() and
cma_free_folio().
Link: https://lkml.kernel.org/r/20240814035451.773331-3-yuzhao@xxxxxxxxxx
Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Frank van der Linden <fvdl@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/cma.h | 16 ++++++++++++
mm/cma.c | 55 ++++++++++++++++++++++++++++++------------
2 files changed, 56 insertions(+), 15 deletions(-)
--- a/include/linux/cma.h~mm-cma-add-cma_allocfree_folio
+++ a/include/linux/cma.h
@@ -52,4 +52,20 @@ extern bool cma_release(struct cma *cma,
extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data);
extern void cma_reserve_pages_on_error(struct cma *cma);
+
+#ifdef CONFIG_CMA
+struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp);
+bool cma_free_folio(struct cma *cma, const struct folio *folio);
+#else
+static inline struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp)
+{
+ return NULL;
+}
+
+static inline bool cma_free_folio(struct cma *cma, const struct folio *folio)
+{
+ return false;
+}
+#endif
+
#endif
--- a/mm/cma.c~mm-cma-add-cma_allocfree_folio
+++ a/mm/cma.c
@@ -403,18 +403,8 @@ static void cma_debug_show_areas(struct
spin_unlock_irq(&cma->lock);
}
-/**
- * cma_alloc() - allocate pages from contiguous area
- * @cma: Contiguous memory region for which the allocation is performed.
- * @count: Requested number of pages.
- * @align: Requested alignment of pages (in PAGE_SIZE order).
- * @no_warn: Avoid printing message about failed allocation
- *
- * This function allocates part of contiguous memory on specific
- * contiguous memory area.
- */
-struct page *cma_alloc(struct cma *cma, unsigned long count,
- unsigned int align, bool no_warn)
+static struct page *__cma_alloc(struct cma *cma, unsigned long count,
+ unsigned int align, gfp_t gfp)
{
unsigned long mask, offset;
unsigned long pfn = -1;
@@ -463,8 +453,7 @@ struct page *cma_alloc(struct cma *cma,
pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit);
mutex_lock(&cma_mutex);
- ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA,
- GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0));
+ ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, gfp);
mutex_unlock(&cma_mutex);
if (ret == 0) {
page = pfn_to_page(pfn);
@@ -494,7 +483,7 @@ struct page *cma_alloc(struct cma *cma,
page_kasan_tag_reset(nth_page(page, i));
}
- if (ret && !no_warn) {
+ if (ret && !(gfp & __GFP_NOWARN)) {
pr_err_ratelimited("%s: %s: alloc failed, req-size: %lu pages, ret: %d\n",
__func__, cma->name, count, ret);
cma_debug_show_areas(cma);
@@ -513,6 +502,34 @@ struct page *cma_alloc(struct cma *cma,
return page;
}
+/**
+ * cma_alloc() - allocate pages from contiguous area
+ * @cma: Contiguous memory region for which the allocation is performed.
+ * @count: Requested number of pages.
+ * @align: Requested alignment of pages (in PAGE_SIZE order).
+ * @no_warn: Avoid printing message about failed allocation
+ *
+ * This function allocates part of contiguous memory on specific
+ * contiguous memory area.
+ */
+struct page *cma_alloc(struct cma *cma, unsigned long count,
+ unsigned int align, bool no_warn)
+{
+ return __cma_alloc(cma, count, align, GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0));
+}
+
+struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp)
+{
+ struct page *page;
+
+ if (WARN_ON(!order || !(gfp | __GFP_COMP)))
+ return NULL;
+
+ page = __cma_alloc(cma, 1 << order, order, gfp);
+
+ return page ? page_folio(page) : NULL;
+}
+
bool cma_pages_valid(struct cma *cma, const struct page *pages,
unsigned long count)
{
@@ -564,6 +581,14 @@ bool cma_release(struct cma *cma, const
return true;
}
+bool cma_free_folio(struct cma *cma, const struct folio *folio)
+{
+ if (WARN_ON(!folio_test_large(folio)))
+ return false;
+
+ return cma_release(cma, &folio->page, folio_nr_pages(folio));
+}
+
int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data)
{
int i;
_
Patches currently in -mm which might be from yuzhao@xxxxxxxxxx are
mm-hugetlb_vmemmap-dont-synchronize_rcu-without-hvo.patch
mm-swap-reduce-indentation-level.patch
mm-swap-rename-cpu_fbatches-activate.patch
mm-swap-fold-lru_rotate-into-cpu_fbatches.patch
mm-swap-remove-remaining-_fn-suffix.patch
mm-swap-remove-boilerplate.patch
mm-swap-remove-boilerplate-fix.patch
mm-free-zapped-tail-pages-when-splitting-isolated-thp.patch
mm-remap-unused-subpages-to-shared-zeropage-when-splitting-isolated-thp.patch
mm-hugetlb_vmemmap-batch-hvo-work-when-demoting.patch
mm-contig_alloc-support-__gfp_comp.patch
mm-cma-add-cma_allocfree_folio.patch
mm-hugetlb-use-__gfp_comp-for-gigantic-folios.patch
