bootmem: Separate out CONFIG_NO_BOOTMEM code into nobootmem.c

mm/bootmem.c contained code paths for both bootmem and no bootmem
configurations.  They implement about the same set of APIs in
different ways and as a result bootmem.c contains massive amount of
#ifdef CONFIG_NO_BOOTMEM.

Separate out CONFIG_NO_BOOTMEM code into mm/nobootmem.c.  As the
common part is relatively small, duplicate them in nobootmem.c instead
of creating a common file or ifdef'ing in bootmem.c.

The followings are duplicated.

* {min|max}_low_pfn, max_pfn, saved_max_pfn
* free_bootmem_late()
* ___alloc_bootmem()
* __alloc_bootmem_low()

The followings are applicable only to nobootmem and moved verbatim.

* __free_pages_memory()
* free_all_memory_core_early()

The followings are not applicable to nobootmem and omitted in
nobootmem.c.

* reserve_bootmem_node()
* reserve_bootmem()

The rest split function bodies according to CONFIG_NO_BOOTMEM.

Makefile is updated so that only either bootmem.c or nobootmem.c is
built according to CONFIG_NO_BOOTMEM.

This patch doesn't introduce any behavior change.

-tj: Rewrote commit description.

Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 3 insertions, 170 deletions

diff --git a/mm/bootmem.c b/mm/bootmem.c
index 13b0caa9793c..4403e2fbc13d 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -35,7 +35,6 @@ unsigned long max_pfn;
 unsigned long saved_max_pfn;
 #endif
 
-#ifndef CONFIG_NO_BOOTMEM
 bootmem_data_t bootmem_node_data[MAX_NUMNODES] __initdata;
 
 static struct list_head bdata_list __initdata = LIST_HEAD_INIT(bdata_list);
@@ -146,7 +145,7 @@ unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
         min_low_pfn = start;
         return init_bootmem_core(NODE_DATA(0)->bdata, start, 0, pages);
 }
-#endif
+
 /*
  * free_bootmem_late - free bootmem pages directly to page allocator
  * @addr: starting address of the range
@@ -171,53 +170,6 @@ void __init free_bootmem_late(unsigned long addr, unsigned long size)
         }
 }
 
-#ifdef CONFIG_NO_BOOTMEM
-static void __init __free_pages_memory(unsigned long start, unsigned long end)
-{
-        int i;
-        unsigned long start_aligned, end_aligned;
-        int order = ilog2(BITS_PER_LONG);
-
-        start_aligned = (start + (BITS_PER_LONG - 1)) & ~(BITS_PER_LONG - 1);
-        end_aligned = end & ~(BITS_PER_LONG - 1);
-
-        if (end_aligned <= start_aligned) {
-                for (i = start; i < end; i++)
-                        __free_pages_bootmem(pfn_to_page(i), 0);
-
-                return;
-        }
-
-        for (i = start; i < start_aligned; i++)
-                __free_pages_bootmem(pfn_to_page(i), 0);
-
-        for (i = start_aligned; i < end_aligned; i += BITS_PER_LONG)
-                __free_pages_bootmem(pfn_to_page(i), order);
-
-        for (i = end_aligned; i < end; i++)
-                __free_pages_bootmem(pfn_to_page(i), 0);
-}
-
-unsigned long __init free_all_memory_core_early(int nodeid)
-{
-        int i;
-        u64 start, end;
-        unsigned long count = 0;
-        struct range *range = NULL;
-        int nr_range;
-
-        nr_range = get_free_all_memory_range(&range, nodeid);
-
-        for (i = 0; i < nr_range; i++) {
-                start = range[i].start;
-                end = range[i].end;
-                count += end - start;
-                __free_pages_memory(start, end);
-        }
-
-        return count;
-}
-#else
 static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 {
         int aligned;
@@ -278,7 +230,6 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 
         return count;
 }
-#endif
 
 /**
  * free_all_bootmem_node - release a node's free pages to the buddy allocator
@@ -289,12 +240,7 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
 {
         register_page_bootmem_info_node(pgdat);
-#ifdef CONFIG_NO_BOOTMEM
-        /* free_all_memory_core_early(MAX_NUMNODES) will be called later */
-        return 0;
-#else
         return free_all_bootmem_core(pgdat->bdata);
-#endif
 }
 
 /**
@@ -304,16 +250,6 @@ unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
  */
 unsigned long __init free_all_bootmem(void)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        /*
-         * We need to use MAX_NUMNODES instead of NODE_DATA(0)->node_id
-         *  because in some case like Node0 doesnt have RAM installed
-         *  low ram will be on Node1
-         * Use MAX_NUMNODES will make sure all ranges in early_node_map[]
-         *  will be used instead of only Node0 related
-         */
-        return free_all_memory_core_early(MAX_NUMNODES);
-#else
         unsigned long total_pages = 0;
         bootmem_data_t *bdata;
 
@@ -321,10 +257,8 @@ unsigned long __init free_all_bootmem(void)
                 total_pages += free_all_bootmem_core(bdata);
 
         return total_pages;
-#endif
 }
 
-#ifndef CONFIG_NO_BOOTMEM
 static void __init __free(bootmem_data_t *bdata,
                         unsigned long sidx, unsigned long eidx)
 {
@@ -419,7 +353,6 @@ static int __init mark_bootmem(unsigned long start, unsigned long end,
         }
         BUG();
 }
-#endif
 
 /**
  * free_bootmem_node - mark a page range as usable
@@ -434,10 +367,6 @@ static int __init mark_bootmem(unsigned long start, unsigned long end,
 void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
                               unsigned long size)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        kmemleak_free_part(__va(physaddr), size);
-        memblock_x86_free_range(physaddr, physaddr + size);
-#else
         unsigned long start, end;
 
         kmemleak_free_part(__va(physaddr), size);
@@ -446,7 +375,6 @@ void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
         end = PFN_DOWN(physaddr + size);
 
         mark_bootmem_node(pgdat->bdata, start, end, 0, 0);
-#endif
 }
 
 /**
@@ -460,10 +388,6 @@ void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
  */
 void __init free_bootmem(unsigned long addr, unsigned long size)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        kmemleak_free_part(__va(addr), size);
-        memblock_x86_free_range(addr, addr + size);
-#else
         unsigned long start, end;
 
         kmemleak_free_part(__va(addr), size);
@@ -472,7 +396,6 @@ void __init free_bootmem(unsigned long addr, unsigned long size)
         end = PFN_DOWN(addr + size);
 
         mark_bootmem(start, end, 0, 0);
-#endif
 }
 
 /**
@@ -489,17 +412,12 @@ void __init free_bootmem(unsigned long addr, unsigned long size)
 int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
                                  unsigned long size, int flags)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        panic("no bootmem");
-        return 0;
-#else
         unsigned long start, end;
 
         start = PFN_DOWN(physaddr);
         end = PFN_UP(physaddr + size);
 
         return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
-#endif
 }
 
 /**
@@ -515,20 +433,14 @@ int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
 int __init reserve_bootmem(unsigned long addr, unsigned long size,
                             int flags)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        panic("no bootmem");
-        return 0;
-#else
         unsigned long start, end;
 
         start = PFN_DOWN(addr);
         end = PFN_UP(addr + size);
 
         return mark_bootmem(start, end, 1, flags);
-#endif
 }
 
-#ifndef CONFIG_NO_BOOTMEM
 int __weak __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
                                    int flags)
 {
@@ -685,33 +597,12 @@ static void * __init alloc_arch_preferred_bootmem(bootmem_data_t *bdata,
 #endif
         return NULL;
 }
-#endif
 
 static void * __init ___alloc_bootmem_nopanic(unsigned long size,
                                         unsigned long align,
                                         unsigned long goal,
                                         unsigned long limit)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        void *ptr;
-
-        if (WARN_ON_ONCE(slab_is_available()))
-                return kzalloc(size, GFP_NOWAIT);
-
-restart:
-
-        ptr = __alloc_memory_core_early(MAX_NUMNODES, size, align, goal, limit);
-
-        if (ptr)
-                return ptr;
-
-        if (goal != 0) {
-                goal = 0;
-                goto restart;
-        }
-
-        return NULL;
-#else
         bootmem_data_t *bdata;
         void *region;
 
@@ -737,7 +628,6 @@ restart:
         }
 
         return NULL;
-#endif
 }
 
 /**
@@ -758,10 +648,6 @@ void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
 {
         unsigned long limit = 0;
 
-#ifdef CONFIG_NO_BOOTMEM
-        limit = -1UL;
-#endif
-
         return ___alloc_bootmem_nopanic(size, align, goal, limit);
 }
 
@@ -798,14 +684,9 @@ void * __init __alloc_bootmem(unsigned long size, unsigned long align,
 {
         unsigned long limit = 0;
 
-#ifdef CONFIG_NO_BOOTMEM
-        limit = -1UL;
-#endif
-
         return ___alloc_bootmem(size, align, goal, limit);
 }
 
-#ifndef CONFIG_NO_BOOTMEM
 static void * __init ___alloc_bootmem_node(bootmem_data_t *bdata,
                                 unsigned long size, unsigned long align,
                                 unsigned long goal, unsigned long limit)
@@ -822,7 +703,6 @@ static void * __init ___alloc_bootmem_node(bootmem_data_t *bdata,
 
         return ___alloc_bootmem(size, align, goal, limit);
 }
-#endif
 
 /**
  * __alloc_bootmem_node - allocate boot memory from a specific node
@@ -842,24 +722,10 @@ static void * __init ___alloc_bootmem_node(bootmem_data_t *bdata,
 void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
                                    unsigned long align, unsigned long goal)
 {
-        void *ptr;
-
         if (WARN_ON_ONCE(slab_is_available()))
                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 
-#ifdef CONFIG_NO_BOOTMEM
-        ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
-                                         goal, -1ULL);
-        if (ptr)
-                return ptr;
-
-        ptr = __alloc_memory_core_early(MAX_NUMNODES, size, align,
-                                         goal, -1ULL);
-#else
-        ptr = ___alloc_bootmem_node(pgdat->bdata, size, align, goal, 0);
-#endif
-
-        return ptr;
+        return  ___alloc_bootmem_node(pgdat->bdata, size, align, goal, 0);
 }
 
 void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
@@ -880,13 +746,8 @@ void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
                 unsigned long new_goal;
 
                 new_goal = MAX_DMA32_PFN << PAGE_SHIFT;
-#ifdef CONFIG_NO_BOOTMEM
-                ptr =  __alloc_memory_core_early(pgdat->node_id, size, align,
-                                                 new_goal, -1ULL);
-#else
                 ptr = alloc_bootmem_core(pgdat->bdata, size, align,
                                                  new_goal, 0);
-#endif
                 if (ptr)
                         return ptr;
         }
@@ -907,16 +768,6 @@ void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
 void * __init alloc_bootmem_section(unsigned long size,
                                     unsigned long section_nr)
 {
-#ifdef CONFIG_NO_BOOTMEM
-        unsigned long pfn, goal, limit;
-
-        pfn = section_nr_to_pfn(section_nr);
-        goal = pfn << PAGE_SHIFT;
-        limit = section_nr_to_pfn(section_nr + 1) << PAGE_SHIFT;
-
-        return __alloc_memory_core_early(early_pfn_to_nid(pfn), size,
-                                         SMP_CACHE_BYTES, goal, limit);
-#else
         bootmem_data_t *bdata;
         unsigned long pfn, goal, limit;
 
@@ -926,7 +777,6 @@ void * __init alloc_bootmem_section(unsigned long size,
         bdata = &bootmem_node_data[early_pfn_to_nid(pfn)];
 
         return alloc_bootmem_core(bdata, size, SMP_CACHE_BYTES, goal, limit);
-#endif
 }
 #endif
 
@@ -938,16 +788,11 @@ void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
         if (WARN_ON_ONCE(slab_is_available()))
                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 
-#ifdef CONFIG_NO_BOOTMEM
-        ptr =  __alloc_memory_core_early(pgdat->node_id, size, align,
-                                                 goal, -1ULL);
-#else
         ptr = alloc_arch_preferred_bootmem(pgdat->bdata, size, align, goal, 0);
         if (ptr)
                 return ptr;
 
         ptr = alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
-#endif
         if (ptr)
                 return ptr;
 
@@ -995,21 +840,9 @@ void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
 void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
                                        unsigned long align, unsigned long goal)
 {
-        void *ptr;
-
         if (WARN_ON_ONCE(slab_is_available()))
                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 
-#ifdef CONFIG_NO_BOOTMEM
-        ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
+        return ___alloc_bootmem_node(pgdat->bdata, size, align,
                                 goal, ARCH_LOW_ADDRESS_LIMIT);
-        if (ptr)
-                return ptr;
-        ptr = __alloc_memory_core_early(MAX_NUMNODES, size, align,
-                                goal, ARCH_LOW_ADDRESS_LIMIT);
-#else
-        ptr = ___alloc_bootmem_node(pgdat->bdata, size, align,
-                                goal, ARCH_LOW_ADDRESS_LIMIT);
-#endif
-        return ptr;
 }