mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM

After removal of the DISCONTIGMEM memory model the FLAT_NODE_MEM_MAP
configuration option is equivalent to FLATMEM.

Drop CONFIG_FLAT_NODE_MEM_MAP and use CONFIG_FLATMEM instead.

Link: https://lkml.kernel.org/r/20210608091316.3622-10-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Author: rppt

include/linux/mmzone.h

@@ -788,7 +788,7 @@ typedef struct pglist_data {
 	struct zonelist node_zonelists[MAX_ZONELISTS];
 
 	int nr_zones; /* number of populated zones in this node */
-#ifdef CONFIG_FLAT_NODE_MEM_MAP	/* means !SPARSEMEM */
+#ifdef CONFIG_FLATMEM	/* means !SPARSEMEM */
 	struct page *node_mem_map;
 #ifdef CONFIG_PAGE_EXTENSION
 	struct page_ext *node_page_ext;
@@ -878,7 +878,7 @@ typedef struct pglist_data {
 
 #define node_present_pages(nid)	(NODE_DATA(nid)->node_present_pages)
 #define node_spanned_pages(nid)	(NODE_DATA(nid)->node_spanned_pages)
-#ifdef CONFIG_FLAT_NODE_MEM_MAP
+#ifdef CONFIG_FLATMEM
 #define pgdat_page_nr(pgdat, pagenr)	((pgdat)->node_mem_map + (pagenr))
 #else
 #define pgdat_page_nr(pgdat, pagenr)	pfn_to_page((pgdat)->node_start_pfn + (pagenr))

kernel/crash_core.c

@@ -484,7 +484,7 @@ static int __init crash_save_vmcoreinfo_init(void)
 	VMCOREINFO_OFFSET(page, compound_head);
 	VMCOREINFO_OFFSET(pglist_data, node_zones);
 	VMCOREINFO_OFFSET(pglist_data, nr_zones);
-#ifdef CONFIG_FLAT_NODE_MEM_MAP
+#ifdef CONFIG_FLATMEM
 	VMCOREINFO_OFFSET(pglist_data, node_mem_map);
 #endif
 	VMCOREINFO_OFFSET(pglist_data, node_start_pfn);

mm/Kconfig

@@ -55,10 +55,6 @@ config FLATMEM
 	def_bool y
 	depends on !SPARSEMEM || FLATMEM_MANUAL
 
-config FLAT_NODE_MEM_MAP
-	def_bool y
-	depends on !SPARSEMEM
-
 #
 # SPARSEMEM_EXTREME (which is the default) does some bootmem
 # allocations when sparse_init() is called.  If this cannot

mm/page_alloc.c

@@ -6547,7 +6547,7 @@ static void __meminit zone_init_free_lists(struct zone *zone)
 	}
 }
 
-#if !defined(CONFIG_FLAT_NODE_MEM_MAP)
+#if !defined(CONFIG_FLATMEM)
 /*
  * Only struct pages that correspond to ranges defined by memblock.memory
  * are zeroed and initialized by going through __init_single_page() during
@@ -7403,7 +7403,7 @@ static void __init free_area_init_core(struct pglist_data *pgdat)
 	}
 }
 
-#ifdef CONFIG_FLAT_NODE_MEM_MAP
+#ifdef CONFIG_FLATMEM
 static void __ref alloc_node_mem_map(struct pglist_data *pgdat)
 {
 	unsigned long __maybe_unused start = 0;
@@ -7451,7 +7451,7 @@ static void __ref alloc_node_mem_map(struct pglist_data *pgdat)
 }
 #else
 static void __ref alloc_node_mem_map(struct pglist_data *pgdat) { }
-#endif /* CONFIG_FLAT_NODE_MEM_MAP */
+#endif /* CONFIG_FLATMEM */
 
 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
 static inline void pgdat_set_deferred_range(pg_data_t *pgdat)

mm/page_ext.c

@@ -191,7 +191,7 @@ void __init page_ext_init_flatmem(void)
 	panic("Out of memory");
 }
 
-#else /* CONFIG_FLAT_NODE_MEM_MAP */
+#else /* CONFIG_FLATMEM */
 
 struct page_ext *lookup_page_ext(const struct page *page)
 {