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authorJohannes Weiner <hannes@saeurebad.de>2008-07-24 00:28:01 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-24 13:47:19 -0400
commita66fd7daec1f40c1f0eac466f0da9206b615fe2a (patch)
tree76a9e76d4bbe68ed87f83d1f95651f9a4310ab2a /mm
parent57cfc29efac6670355ee0e107c8dbae8237d406b (diff)
bootmem: add documentation to API functions
Signed-off-by: Johannes Weiner <hannes@saeurebad.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/bootmem.c150
1 files changed, 149 insertions, 1 deletions
diff --git a/mm/bootmem.c b/mm/bootmem.c
index 286e12c536a..105ad4cff2e 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -47,7 +47,10 @@ static unsigned long __init get_mapsize(bootmem_data_t *bdata)
47 return ALIGN(mapsize, sizeof(long)); 47 return ALIGN(mapsize, sizeof(long));
48} 48}
49 49
50/* return the number of _pages_ that will be allocated for the boot bitmap */ 50/**
51 * bootmem_bootmap_pages - calculate bitmap size in pages
52 * @pages: number of pages the bitmap has to represent
53 */
51unsigned long __init bootmem_bootmap_pages(unsigned long pages) 54unsigned long __init bootmem_bootmap_pages(unsigned long pages)
52{ 55{
53 unsigned long mapsize; 56 unsigned long mapsize;
@@ -104,12 +107,28 @@ static unsigned long __init init_bootmem_core(bootmem_data_t *bdata,
104 return mapsize; 107 return mapsize;
105} 108}
106 109
110/**
111 * init_bootmem_node - register a node as boot memory
112 * @pgdat: node to register
113 * @freepfn: pfn where the bitmap for this node is to be placed
114 * @startpfn: first pfn on the node
115 * @endpfn: first pfn after the node
116 *
117 * Returns the number of bytes needed to hold the bitmap for this node.
118 */
107unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn, 119unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
108 unsigned long startpfn, unsigned long endpfn) 120 unsigned long startpfn, unsigned long endpfn)
109{ 121{
110 return init_bootmem_core(pgdat->bdata, freepfn, startpfn, endpfn); 122 return init_bootmem_core(pgdat->bdata, freepfn, startpfn, endpfn);
111} 123}
112 124
125/**
126 * init_bootmem - register boot memory
127 * @start: pfn where the bitmap is to be placed
128 * @pages: number of available physical pages
129 *
130 * Returns the number of bytes needed to hold the bitmap.
131 */
113unsigned long __init init_bootmem(unsigned long start, unsigned long pages) 132unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
114{ 133{
115 max_low_pfn = pages; 134 max_low_pfn = pages;
@@ -182,12 +201,23 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
182 return count; 201 return count;
183} 202}
184 203
204/**
205 * free_all_bootmem_node - release a node's free pages to the buddy allocator
206 * @pgdat: node to be released
207 *
208 * Returns the number of pages actually released.
209 */
185unsigned long __init free_all_bootmem_node(pg_data_t *pgdat) 210unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
186{ 211{
187 register_page_bootmem_info_node(pgdat); 212 register_page_bootmem_info_node(pgdat);
188 return free_all_bootmem_core(pgdat->bdata); 213 return free_all_bootmem_core(pgdat->bdata);
189} 214}
190 215
216/**
217 * free_all_bootmem - release free pages to the buddy allocator
218 *
219 * Returns the number of pages actually released.
220 */
191unsigned long __init free_all_bootmem(void) 221unsigned long __init free_all_bootmem(void)
192{ 222{
193 return free_all_bootmem_core(NODE_DATA(0)->bdata); 223 return free_all_bootmem_core(NODE_DATA(0)->bdata);
@@ -231,12 +261,32 @@ static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
231 } 261 }
232} 262}
233 263
264/**
265 * free_bootmem_node - mark a page range as usable
266 * @pgdat: node the range resides on
267 * @physaddr: starting address of the range
268 * @size: size of the range in bytes
269 *
270 * Partial pages will be considered reserved and left as they are.
271 *
272 * Only physical pages that actually reside on @pgdat are marked.
273 */
234void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr, 274void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
235 unsigned long size) 275 unsigned long size)
236{ 276{
237 free_bootmem_core(pgdat->bdata, physaddr, size); 277 free_bootmem_core(pgdat->bdata, physaddr, size);
238} 278}
239 279
280/**
281 * free_bootmem - mark a page range as usable
282 * @addr: starting address of the range
283 * @size: size of the range in bytes
284 *
285 * Partial pages will be considered reserved and left as they are.
286 *
287 * All physical pages within the range are marked, no matter what
288 * node they reside on.
289 */
240void __init free_bootmem(unsigned long addr, unsigned long size) 290void __init free_bootmem(unsigned long addr, unsigned long size)
241{ 291{
242 bootmem_data_t *bdata; 292 bootmem_data_t *bdata;
@@ -319,6 +369,17 @@ static void __init reserve_bootmem_core(bootmem_data_t *bdata,
319 } 369 }
320} 370}
321 371
372/**
373 * reserve_bootmem_node - mark a page range as reserved
374 * @pgdat: node the range resides on
375 * @physaddr: starting address of the range
376 * @size: size of the range in bytes
377 * @flags: reservation flags (see linux/bootmem.h)
378 *
379 * Partial pages will be reserved.
380 *
381 * Only physical pages that actually reside on @pgdat are marked.
382 */
322int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr, 383int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
323 unsigned long size, int flags) 384 unsigned long size, int flags)
324{ 385{
@@ -332,6 +393,17 @@ int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
332} 393}
333 394
334#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE 395#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
396/**
397 * reserve_bootmem - mark a page range as usable
398 * @addr: starting address of the range
399 * @size: size of the range in bytes
400 * @flags: reservation flags (see linux/bootmem.h)
401 *
402 * Partial pages will be reserved.
403 *
404 * All physical pages within the range are marked, no matter what
405 * node they reside on.
406 */
335int __init reserve_bootmem(unsigned long addr, unsigned long size, 407int __init reserve_bootmem(unsigned long addr, unsigned long size,
336 int flags) 408 int flags)
337{ 409{
@@ -500,6 +572,19 @@ found:
500 return ret; 572 return ret;
501} 573}
502 574
575/**
576 * __alloc_bootmem_nopanic - allocate boot memory without panicking
577 * @size: size of the request in bytes
578 * @align: alignment of the region
579 * @goal: preferred starting address of the region
580 *
581 * The goal is dropped if it can not be satisfied and the allocation will
582 * fall back to memory below @goal.
583 *
584 * Allocation may happen on any node in the system.
585 *
586 * Returns NULL on failure.
587 */
503void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align, 588void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
504 unsigned long goal) 589 unsigned long goal)
505{ 590{
@@ -514,6 +599,19 @@ void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
514 return NULL; 599 return NULL;
515} 600}
516 601
602/**
603 * __alloc_bootmem - allocate boot memory
604 * @size: size of the request in bytes
605 * @align: alignment of the region
606 * @goal: preferred starting address of the region
607 *
608 * The goal is dropped if it can not be satisfied and the allocation will
609 * fall back to memory below @goal.
610 *
611 * Allocation may happen on any node in the system.
612 *
613 * The function panics if the request can not be satisfied.
614 */
517void * __init __alloc_bootmem(unsigned long size, unsigned long align, 615void * __init __alloc_bootmem(unsigned long size, unsigned long align,
518 unsigned long goal) 616 unsigned long goal)
519{ 617{
@@ -529,6 +627,21 @@ void * __init __alloc_bootmem(unsigned long size, unsigned long align,
529 return NULL; 627 return NULL;
530} 628}
531 629
630/**
631 * __alloc_bootmem_node - allocate boot memory from a specific node
632 * @pgdat: node to allocate from
633 * @size: size of the request in bytes
634 * @align: alignment of the region
635 * @goal: preferred starting address of the region
636 *
637 * The goal is dropped if it can not be satisfied and the allocation will
638 * fall back to memory below @goal.
639 *
640 * Allocation may fall back to any node in the system if the specified node
641 * can not hold the requested memory.
642 *
643 * The function panics if the request can not be satisfied.
644 */
532void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size, 645void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
533 unsigned long align, unsigned long goal) 646 unsigned long align, unsigned long goal)
534{ 647{
@@ -542,6 +655,13 @@ void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
542} 655}
543 656
544#ifdef CONFIG_SPARSEMEM 657#ifdef CONFIG_SPARSEMEM
658/**
659 * alloc_bootmem_section - allocate boot memory from a specific section
660 * @size: size of the request in bytes
661 * @section_nr: sparse map section to allocate from
662 *
663 * Return NULL on failure.
664 */
545void * __init alloc_bootmem_section(unsigned long size, 665void * __init alloc_bootmem_section(unsigned long size,
546 unsigned long section_nr) 666 unsigned long section_nr)
547{ 667{
@@ -588,6 +708,19 @@ void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
588#define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL 708#define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
589#endif 709#endif
590 710
711/**
712 * __alloc_bootmem_low - allocate low boot memory
713 * @size: size of the request in bytes
714 * @align: alignment of the region
715 * @goal: preferred starting address of the region
716 *
717 * The goal is dropped if it can not be satisfied and the allocation will
718 * fall back to memory below @goal.
719 *
720 * Allocation may happen on any node in the system.
721 *
722 * The function panics if the request can not be satisfied.
723 */
591void * __init __alloc_bootmem_low(unsigned long size, unsigned long align, 724void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
592 unsigned long goal) 725 unsigned long goal)
593{ 726{
@@ -609,6 +742,21 @@ void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
609 return NULL; 742 return NULL;
610} 743}
611 744
745/**
746 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
747 * @pgdat: node to allocate from
748 * @size: size of the request in bytes
749 * @align: alignment of the region
750 * @goal: preferred starting address of the region
751 *
752 * The goal is dropped if it can not be satisfied and the allocation will
753 * fall back to memory below @goal.
754 *
755 * Allocation may fall back to any node in the system if the specified node
756 * can not hold the requested memory.
757 *
758 * The function panics if the request can not be satisfied.
759 */
612void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size, 760void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
613 unsigned long align, unsigned long goal) 761 unsigned long align, unsigned long goal)
614{ 762{