/**
* pcpu_map_pages - map pages into a pcpu_chunk
* @chunk: chunk of interest
* @pages: pages array containing pages to be mapped
* @populated: populated bitmap
* @page_start: page index of the first page to map
* @page_end: page index of the last page to map + 1
*
* For each cpu, map pages [@page_start,@page_end) into @chunk. The
* caller is responsible for calling pcpu_post_map_flush() after all
* mappings are complete.
*
* This function is responsible for setting corresponding bits in
* @chunk->populated bitmap and whatever is necessary for reverse
* lookup (addr -> chunk).
*/
static int pcpu_map_pages(struct pcpu_chunk *chunk,
struct page **pages, unsigned long *populated,
int page_start, int page_end)
{
unsigned int cpu, tcpu;
int i, err;
for_each_possible_cpu(cpu) {
err = __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start),
&pages[pcpu_page_idx(cpu, page_start)],
page_end - page_start);
if (err < 0)
goto err;
}
/* mapping successful, link chunk and mark populated */
for (i = page_start; i < page_end; i++) {
for_each_possible_cpu(cpu)
pcpu_set_page_chunk(pages[pcpu_page_idx(cpu, i)],
chunk);
__set_bit(i, populated);
}
return 0;
err:
for_each_possible_cpu(tcpu) {
if (tcpu == cpu)
break;
__pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start),
page_end - page_start);
}
return err;
}
/**
* pcpu_alloc_pages - allocates pages for @chunk
* @chunk: target chunk
* @pages: array to put the allocated pages into, indexed by pcpu_page_idx()
* @page_start: page index of the first page to be allocated
* @page_end: page index of the last page to be allocated + 1
*
* Allocate pages [@page_start,@page_end) into @pages for all units.
* The allocation is for @chunk. Percpu core doesn't care about the
* content of @pages and will pass it verbatim to pcpu_map_pages().
*/
static int pcpu_alloc_pages(struct pcpu_chunk *chunk,
struct page **pages, int page_start, int page_end)
{
const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM;
unsigned int cpu, tcpu;
int i;
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
struct page **pagep = &pages[pcpu_page_idx(cpu, i)];
*pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0);
if (!*pagep)
goto err;
}
}
return 0;
err:
while (--i >= page_start)
__free_page(pages[pcpu_page_idx(cpu, i)]);
for_each_possible_cpu(tcpu) {
if (tcpu == cpu)
break;
for (i = page_start; i < page_end; i++)
__free_page(pages[pcpu_page_idx(tcpu, i)]);
}
return -ENOMEM;
}
/**
* pcpu_map_pages - map pages into a pcpu_chunk
* @chunk: chunk of interest
* @pages: pages array containing pages to be mapped
* @page_start: page index of the first page to map
* @page_end: page index of the last page to map + 1
*
* For each cpu, map pages [@page_start,@page_end) into @chunk. The
* caller is responsible for calling pcpu_post_map_flush() after all
* mappings are complete.
*
* This function is responsible for setting up whatever is necessary for
* reverse lookup (addr -> chunk).
*/
static int pcpu_map_pages(struct pcpu_chunk *chunk,
struct page **pages, int page_start, int page_end)
{
unsigned int cpu, tcpu;
int i, err;
for_each_possible_cpu(cpu) {
err = __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start),
&pages[pcpu_page_idx(cpu, page_start)],
page_end - page_start);
if (err < 0)
goto err;
for (i = page_start; i < page_end; i++)
pcpu_set_page_chunk(pages[pcpu_page_idx(cpu, i)],
chunk);
}
return 0;
err:
for_each_possible_cpu(tcpu) {
if (tcpu == cpu)
break;
__pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start),
page_end - page_start);
}
pcpu_post_unmap_tlb_flush(chunk, page_start, page_end);
return err;
}
/**
* pcpu_alloc_pages - allocates pages for @chunk
* @chunk: target chunk
* @pages: array to put the allocated pages into, indexed by pcpu_page_idx()
* @populated: populated bitmap
* @page_start: page index of the first page to be allocated
* @page_end: page index of the last page to be allocated + 1
*
* Allocate pages [@page_start,@page_end) into @pages for all units.
* The allocation is for @chunk. Percpu core doesn't care about the
* content of @pages and will pass it verbatim to pcpu_map_pages().
*/
static int pcpu_alloc_pages(struct pcpu_chunk *chunk,
struct page **pages, unsigned long *populated,
int page_start, int page_end)
{
const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD;
unsigned int cpu;
int nid;
int i;
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
struct page **pagep = &pages[pcpu_page_idx(cpu, i)];
//*pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0);
nid = cpu_to_node(cpu);
if((nid == -1) || !(node_zonelist(nid, GFP_KERNEL)->_zonerefs->zone))
nid = numa_node_id();
*pagep = alloc_pages_node(nid, gfp, 0);
if (!*pagep) {
pcpu_free_pages(chunk, pages, populated,
page_start, page_end);
return -ENOMEM;
}
}
}
return 0;
}
/*! 2016-04-02 study -ing */
static int pcpu_alloc_pages(struct pcpu_chunk *chunk,
struct page **pages, unsigned long *populated,
int page_start, int page_end)
{
const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD;
unsigned int cpu;
int i;
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
/*! pages에서 pcpu page 의 index에 해당하는 위치를 찾는다.
* (pages 는 포인터 배열)
*/
struct page **pagep = &pages[pcpu_page_idx(cpu, i)];
/*! 해당 위치에 pages node alloc */
*pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0);
if (!*pagep) {
/*! alloc 실패 시 free */
pcpu_free_pages(chunk, pages, populated,
page_start, page_end);
return -ENOMEM;
}
}
}
return 0;
}
/**
* pcpu_free_pages - free pages which were allocated for @chunk
* @chunk: chunk pages were allocated for
* @pages: array of pages to be freed, indexed by pcpu_page_idx()
* @page_start: page index of the first page to be freed
* @page_end: page index of the last page to be freed + 1
*
* Free pages [@page_start and @page_end) in @pages for all units.
* The pages were allocated for @chunk.
*/
static void pcpu_free_pages(struct pcpu_chunk *chunk,
struct page **pages, int page_start, int page_end)
{
unsigned int cpu;
int i;
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
struct page *page = pages[pcpu_page_idx(cpu, i)];
if (page)
__free_page(page);
}
}
}
/**
* pcpu_unmap_pages - unmap pages out of a pcpu_chunk
* @chunk: chunk of interest
* @pages: pages array which can be used to pass information to free
* @page_start: page index of the first page to unmap
* @page_end: page index of the last page to unmap + 1
*
* For each cpu, unmap pages [@page_start,@page_end) out of @chunk.
* Corresponding elements in @pages were cleared by the caller and can
* be used to carry information to pcpu_free_pages() which will be
* called after all unmaps are finished. The caller should call
* proper pre/post flush functions.
*/
static void pcpu_unmap_pages(struct pcpu_chunk *chunk,
struct page **pages, int page_start, int page_end)
{
unsigned int cpu;
int i;
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
struct page *page;
page = pcpu_chunk_page(chunk, cpu, i);
WARN_ON(!page);
pages[pcpu_page_idx(cpu, i)] = page;
}
__pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start),
page_end - page_start);
}
}
static int pcpu_alloc_pages(struct pcpu_chunk *chunk,
struct page **pages, unsigned long *populated,
int page_start, int page_end)
{
const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD;
unsigned int cpu;
int i;
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
struct page **pagep = &pages[pcpu_page_idx(cpu, i)];
*pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0);
if (!*pagep) {
pcpu_free_pages(chunk, pages, populated,
page_start, page_end);
return -ENOMEM;
}
}
}
return 0;
}
/*! 2016-04-02 study -ing */
static void pcpu_unmap_pages(struct pcpu_chunk *chunk,
struct page **pages, unsigned long *populated,
int page_start, int page_end)
{
unsigned int cpu;
int i;
/*! cpu 갯수 loop */
for_each_possible_cpu(cpu) {
for (i = page_start; i < page_end; i++) {
struct page *page;
page = pcpu_chunk_page(chunk, cpu, i);
WARN_ON(!page);
pages[pcpu_page_idx(cpu, i)] = page;
}
/*! pgd->pud->pmd->pte 순으로 clear 수행 */
__pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start),
page_end - page_start);
}
/*! page_start 부터 page_end - page_start 갯수 만큼 populated의 bitmap clear */
bitmap_clear(populated, page_start, page_end - page_start);
}
