kevin/linux
1
Fork 0
Code

mm/cma: add cma_{alloc,free}_folio()

Browse Source 
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().

[yuzhao@google.com: fix WARN in cma_alloc_folio()]
  Link: https://lkml.kernel.org/r/Zsd0PgAQmbpR8jS6@google.com
Link: https://lkml.kernel.org/r/20240814035451.773331-3-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Yu Zhao 2024-08-13 21:54:50 -06:00 committed by Andrew Morton
parent e98337d11b
commit 463586e9ff
2 changed files with 56 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
include/linux/cma.h
View File

@ -52,4 +52,20 @@ extern bool cma_release(struct cma *cma, const struct page *pages, unsigned long
extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data); 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); 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 #endif

55
mm/cma.c
View File

@ -403,18 +403,8 @@ static void cma_debug_show_areas(struct cma *cma)
spin_unlock_irq(&cma->lock); spin_unlock_irq(&cma->lock);
} }
/** static struct page *__cma_alloc(struct cma *cma, unsigned long count,
* cma_alloc() - allocate pages from contiguous area unsigned int align, gfp_t gfp)
* @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)
{ {
unsigned long mask, offset; unsigned long mask, offset;
unsigned long pfn = -1; unsigned long pfn = -1;
@ -463,8 +453,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit);
mutex_lock(&cma_mutex); mutex_lock(&cma_mutex);
ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, gfp);
GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0));
mutex_unlock(&cma_mutex); mutex_unlock(&cma_mutex);
if (ret == 0) { if (ret == 0) {
page = pfn_to_page(pfn); page = pfn_to_page(pfn);
@ -494,7 +483,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
page_kasan_tag_reset(nth_page(page, i)); 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", pr_err_ratelimited("%s: %s: alloc failed, req-size: %lu pages, ret: %d\n",
__func__, cma->name, count, ret); __func__, cma->name, count, ret);
cma_debug_show_areas(cma); cma_debug_show_areas(cma);
@ -513,6 +502,34 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
return page; 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, bool cma_pages_valid(struct cma *cma, const struct page *pages,
unsigned long count) unsigned long count)
{ {
@ -564,6 +581,14 @@ bool cma_release(struct cma *cma, const struct page *pages,
return true; 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 cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data)
{ {
int i; int i;