mm/hugetlb: rename dissolve_free_huge_pages() to dissolve_free_hugetlb_folios()

dissolve_free_huge_pages() only uses folios internally, rename it to
dissolve_free_hugetlb_folios() and change the comments which reference it.

[akpm@linux-foundation.org: remove unneeded `extern']
Link: https://lkml.kernel.org/r/20240412182139.120871-2-sidhartha.kumar@oracle.comSigned-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/hugetlb.h

@@ -862,7 +862,7 @@ static inline int hstate_index(struct hstate *h)
 }
 
 int dissolve_free_hugetlb_folio(struct folio *folio);
-extern int dissolve_free_huge_pages(unsigned long start_pfn,
+int dissolve_free_hugetlb_folios(unsigned long start_pfn,
 				    unsigned long end_pfn);
 
 #ifdef CONFIG_MEMORY_FAILURE
@@ -1153,7 +1153,7 @@ static inline int dissolve_free_hugetlb_folio(struct folio *folio)
 	return 0;
 }
 
-static inline int dissolve_free_huge_pages(unsigned long start_pfn,
+static inline int dissolve_free_hugetlb_folios(unsigned long start_pfn,
 					   unsigned long end_pfn)
 {
 	return 0;

mm/hugetlb.c

@@ -2472,7 +2472,7 @@ int dissolve_free_hugetlb_folio(struct folio *folio)
  * Also note that if dissolve_free_hugetlb_folio() returns with an error, all
  * free hugetlb folios that were dissolved before that error are lost.
  */
-int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn)
+int dissolve_free_hugetlb_folios(unsigned long start_pfn, unsigned long end_pfn)
 {
 	unsigned long pfn;
 	struct folio *folio;

mm/memory_hotplug.c

@@ -2051,11 +2051,11 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages,
 		}
 
 		/*
-		 * Dissolve free hugepages in the memory block before doing
+		 * Dissolve free hugetlb folios in the memory block before doing
 		 * offlining actually in order to make hugetlbfs's object
 		 * counting consistent.
 		 */
-		ret = dissolve_free_huge_pages(start_pfn, end_pfn);
+		ret = dissolve_free_hugetlb_folios(start_pfn, end_pfn);
 		if (ret) {
 			reason = "failure to dissolve huge pages";
 			goto failed_removal_isolated;