[PATCH v3 4/6] mm: cma: add __cma_release()

[Kefeng Wang <wangkefeng.wang@huawei.com>]

Kill cma_pages_valid() which only used in cma_release(), also
cleanup code duplication between cma pages valid checking and
cma memrange finding, add __cma_release() helper to prepare for
the upcoming frozen page release.

Reviewed-by: Jane Chu <jane.chu@oracle.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 include/linux/cma.h |  1 -
 mm/cma.c            | 62 +++++++++++++++------------------------------
 2 files changed, 21 insertions(+), 42 deletions(-)

diff --git a/include/linux/cma.h b/include/linux/cma.h
index 62d9c1cf6326..e5745d2aec55 100644
--- a/include/linux/cma.h
+++ b/include/linux/cma.h
@@ -49,7 +49,6 @@ 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 813e6dc7b095..88016f4aef7f 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -942,34 +942,43 @@ struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp)
 	return page ? page_folio(page) : NULL;
 }
 
-bool cma_pages_valid(struct cma *cma, const struct page *pages,
-		     unsigned long count)
+static bool __cma_release(struct cma *cma, const struct page *pages,
+			  unsigned long count)
 {
 	unsigned long pfn, end;
 	int r;
 	struct cma_memrange *cmr;
-	bool ret;
+
+	pr_debug("%s(page %p, count %lu)\n", __func__, (void *)pages, count);
 
 	if (!cma || !pages || count > cma->count)
 		return false;
 
 	pfn = page_to_pfn(pages);
-	ret = false;
 
 	for (r = 0; r < cma->nranges; r++) {
 		cmr = &cma->ranges[r];
 		end = cmr->base_pfn + cmr->count;
 		if (pfn >= cmr->base_pfn && pfn < end) {
-			ret = pfn + count <= end;
-			break;
+			if (pfn + count <= end)
+				break;
+
+			VM_WARN_ON_ONCE(1);
 		}
 	}
 
-	if (!ret)
-		pr_debug("%s(page %p, count %lu)\n",
-				__func__, (void *)pages, count);
+	if (r == cma->nranges) {
+		pr_debug("%s(no cma range match the page %p)\n",
+			 __func__, (void *)pages);
+		return false;
+	}
 
-	return ret;
+	free_contig_range(pfn, count);
+	cma_clear_bitmap(cma, cmr, pfn, count);
+	cma_sysfs_account_release_pages(cma, count);
+	trace_cma_release(cma->name, pfn, pages, count);
+
+	return true;
 }
 
 /**
@@ -985,36 +994,7 @@ bool cma_pages_valid(struct cma *cma, const struct page *pages,
 bool cma_release(struct cma *cma, const struct page *pages,
 		 unsigned long count)
 {
-	struct cma_memrange *cmr;
-	unsigned long pfn, end_pfn;
-	int r;
-
-	pr_debug("%s(page %p, count %lu)\n", __func__, (void *)pages, count);
-
-	if (!cma_pages_valid(cma, pages, count))
-		return false;
-
-	pfn = page_to_pfn(pages);
-	end_pfn = pfn + count;
-
-	for (r = 0; r < cma->nranges; r++) {
-		cmr = &cma->ranges[r];
-		if (pfn >= cmr->base_pfn &&
-		    pfn < (cmr->base_pfn + cmr->count)) {
-			VM_BUG_ON(end_pfn > cmr->base_pfn + cmr->count);
-			break;
-		}
-	}
-
-	if (r == cma->nranges)
-		return false;
-
-	free_contig_range(pfn, count);
-	cma_clear_bitmap(cma, cmr, pfn, count);
-	cma_sysfs_account_release_pages(cma, count);
-	trace_cma_release(cma->name, pfn, pages, count);
-
-	return true;
+	return __cma_release(cma, pages, count);
 }
 
 bool cma_free_folio(struct cma *cma, const struct folio *folio)
@@ -1022,7 +1002,7 @@ 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));
+	return __cma_release(cma, &folio->page, folio_nr_pages(folio));
 }
 
 int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data)
-- 
2.27.0