From 9871e2ded6c1ff61a59988d7a0e975f012105d52 Mon Sep 17 00:00:00 2001 From: Mike Kravetz Date: Fri, 5 Nov 2021 13:41:23 -0700 Subject: [PATCH] mm/cma: add cma_pages_valid to determine if pages are in CMA Add new interface cma_pages_valid() which indicates if the specified pages are part of a CMA region. This interface will be used in a subsequent patch by hugetlb code. In order to keep the same amount of DEBUG information, a pr_debug() call was added to cma_pages_valid(). In the case where the page passed to cma_release is not in cma region, the debug message will be printed from cma_pages_valid as opposed to cma_release. Link: https://lkml.kernel.org/r/20211007181918.136982-3-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz Acked-by: David Hildenbrand Reviewed-by: Oscar Salvador Cc: "Aneesh Kumar K . V" Cc: David Rientjes Cc: Michal Hocko Cc: Muchun Song Cc: Naoya Horiguchi Cc: Nghia Le Cc: Zi Yan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/cma.h | 1 + mm/cma.c | 24 ++++++++++++++++++++---- 2 files changed, 21 insertions(+), 4 deletions(-) diff --git a/include/linux/cma.h b/include/linux/cma.h index 53fd8c3cdbd0..bd801023504b 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -46,6 +46,7 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, struct cma **res_cma); extern struct page *cma_alloc(struct cma *cma, unsigned long count, unsigned int align, bool no_warn); +extern bool cma_pages_valid(struct cma *cma, const struct page *pages, unsigned long count); extern bool cma_release(struct cma *cma, const struct page *pages, unsigned long count); extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data); diff --git a/mm/cma.c b/mm/cma.c index 995e15480937..11152c3fb23c 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -524,6 +524,25 @@ out: return page; } +bool cma_pages_valid(struct cma *cma, const struct page *pages, + unsigned long count) +{ + unsigned long pfn; + + if (!cma || !pages) + return false; + + pfn = page_to_pfn(pages); + + if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count) { + pr_debug("%s(page %p, count %lu)\n", __func__, + (void *)pages, count); + return false; + } + + return true; +} + /** * cma_release() - release allocated pages * @cma: Contiguous memory region for which the allocation is performed. @@ -539,16 +558,13 @@ bool cma_release(struct cma *cma, const struct page *pages, { unsigned long pfn; - if (!cma || !pages) + if (!cma_pages_valid(cma, pages, count)) return false; pr_debug("%s(page %p, count %lu)\n", __func__, (void *)pages, count); pfn = page_to_pfn(pages); - if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count) - return false; - VM_BUG_ON(pfn + count > cma->base_pfn + cma->count); free_contig_range(pfn, count); -- 2.11.0