Commit 75884fb1 authored by KAMEZAWA Hiroyuki's avatar KAMEZAWA Hiroyuki Committed by Linus Torvalds

memory unplug: memory hotplug cleanup

A clean up patch for "scanning memory resource [start, end)" operation.

Now, find_next_system_ram() function is used in memory hotplug, but this
interface is not easy to use and codes are complicated.

This patch adds walk_memory_resouce(start,len,arg,func) function.
The function 'func' is called per valid memory resouce range in [start,pfn).

[pbadari@us.ibm.com: Error handling in walk_memory_resource()]
Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: default avatarBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 48f13bf3
......@@ -110,9 +110,6 @@ extern int allocate_resource(struct resource *root, struct resource *new,
int adjust_resource(struct resource *res, resource_size_t start,
resource_size_t size);
/* get registered SYSTEM_RAM resources in specified area */
extern int find_next_system_ram(struct resource *res);
/* Convenience shorthand with allocation */
#define request_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name))
#define request_mem_region(start,n,name) __request_region(&iomem_resource, (start), (n), (name))
......
......@@ -63,6 +63,14 @@ extern int online_pages(unsigned long, unsigned long);
extern int __add_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages);
/*
* Walk thorugh all memory which is registered as resource.
* arg is (start_pfn, nr_pages, private_arg_pointer)
*/
extern int walk_memory_resource(unsigned long start_pfn,
unsigned long nr_pages, void *arg,
int (*func)(unsigned long, unsigned long, void *));
#ifdef CONFIG_NUMA
extern int memory_add_physaddr_to_nid(u64 start);
#else
......
......@@ -234,7 +234,7 @@ EXPORT_SYMBOL(release_resource);
* the caller must specify res->start, res->end, res->flags.
* If found, returns 0, res is overwritten, if not found, returns -1.
*/
int find_next_system_ram(struct resource *res)
static int find_next_system_ram(struct resource *res)
{
resource_size_t start, end;
struct resource *p;
......@@ -267,6 +267,30 @@ int find_next_system_ram(struct resource *res)
res->end = p->end;
return 0;
}
int
walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
int (*func)(unsigned long, unsigned long, void *))
{
struct resource res;
unsigned long pfn, len;
u64 orig_end;
int ret = -1;
res.start = (u64) start_pfn << PAGE_SHIFT;
res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
res.flags = IORESOURCE_MEM;
orig_end = res.end;
while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
pfn = (unsigned long)(res.start >> PAGE_SHIFT);
len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT);
ret = (*func)(pfn, len, arg);
if (ret)
break;
res.start = res.end + 1;
res.end = orig_end;
}
return ret;
}
#endif
/*
......
......@@ -161,14 +161,27 @@ static void grow_pgdat_span(struct pglist_data *pgdat,
pgdat->node_start_pfn;
}
int online_pages(unsigned long pfn, unsigned long nr_pages)
static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
void *arg)
{
unsigned long i;
unsigned long onlined_pages = *(unsigned long *)arg;
struct page *page;
if (PageReserved(pfn_to_page(start_pfn)))
for (i = 0; i < nr_pages; i++) {
page = pfn_to_page(start_pfn + i);
online_page(page);
onlined_pages++;
}
*(unsigned long *)arg = onlined_pages;
return 0;
}
int online_pages(unsigned long pfn, unsigned long nr_pages)
{
unsigned long flags;
unsigned long onlined_pages = 0;
struct resource res;
u64 section_end;
unsigned long start_pfn;
struct zone *zone;
int need_zonelists_rebuild = 0;
......@@ -191,28 +204,8 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
if (!populated_zone(zone))
need_zonelists_rebuild = 1;
res.start = (u64)pfn << PAGE_SHIFT;
res.end = res.start + ((u64)nr_pages << PAGE_SHIFT) - 1;
res.flags = IORESOURCE_MEM; /* we just need system ram */
section_end = res.end;
while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
start_pfn = (unsigned long)(res.start >> PAGE_SHIFT);
nr_pages = (unsigned long)
((res.end + 1 - res.start) >> PAGE_SHIFT);
if (PageReserved(pfn_to_page(start_pfn))) {
/* this region's page is not onlined now */
for (i = 0; i < nr_pages; i++) {
struct page *page = pfn_to_page(start_pfn + i);
online_page(page);
onlined_pages++;
}
}
res.start = res.end + 1;
res.end = section_end;
}
walk_memory_resource(pfn, nr_pages, &onlined_pages,
online_pages_range);
zone->present_pages += onlined_pages;
zone->zone_pgdat->node_present_pages += onlined_pages;
......
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