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Diffstat (limited to 'arch/powerpc/mm/init_64.c')
-rw-r--r--arch/powerpc/mm/init_64.c82
1 files changed, 58 insertions, 24 deletions
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index ec84b31c6c86..5b4c25d12ff3 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -44,6 +44,7 @@
#include <linux/slab.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
+#include <linux/memremap.h>
#include <asm/pgalloc.h>
#include <asm/page.h>
@@ -110,8 +111,29 @@ static int __meminit vmemmap_populated(unsigned long start, int page_size)
return 0;
}
+/*
+ * vmemmap virtual address space management does not have a traditonal page
+ * table to track which virtual struct pages are backed by physical mapping.
+ * The virtual to physical mappings are tracked in a simple linked list
+ * format. 'vmemmap_list' maintains the entire vmemmap physical mapping at
+ * all times where as the 'next' list maintains the available
+ * vmemmap_backing structures which have been deleted from the
+ * 'vmemmap_global' list during system runtime (memory hotplug remove
+ * operation). The freed 'vmemmap_backing' structures are reused later when
+ * new requests come in without allocating fresh memory. This pointer also
+ * tracks the allocated 'vmemmap_backing' structures as we allocate one
+ * full page memory at a time when we dont have any.
+ */
struct vmemmap_backing *vmemmap_list;
static struct vmemmap_backing *next;
+
+/*
+ * The same pointer 'next' tracks individual chunks inside the allocated
+ * full page during the boot time and again tracks the freeed nodes during
+ * runtime. It is racy but it does not happen as they are separated by the
+ * boot process. Will create problem if some how we have memory hotplug
+ * operation during boot !!
+ */
static int num_left;
static int num_freed;
@@ -171,13 +193,17 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
pr_debug("vmemmap_populate %lx..%lx, node %d\n", start, end, node);
for (; start < end; start += page_size) {
+ struct vmem_altmap *altmap;
void *p;
int rc;
if (vmemmap_populated(start, page_size))
continue;
- p = vmemmap_alloc_block(page_size, node);
+ /* altmap lookups only work at section boundaries */
+ altmap = to_vmem_altmap(SECTION_ALIGN_DOWN(start));
+
+ p = __vmemmap_alloc_block_buf(page_size, node, altmap);
if (!p)
return -ENOMEM;
@@ -234,13 +260,17 @@ static unsigned long vmemmap_list_free(unsigned long start)
void __ref vmemmap_free(unsigned long start, unsigned long end)
{
unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
+ unsigned long page_order = get_order(page_size);
start = _ALIGN_DOWN(start, page_size);
pr_debug("vmemmap_free %lx...%lx\n", start, end);
for (; start < end; start += page_size) {
- unsigned long addr;
+ unsigned long nr_pages, addr;
+ struct vmem_altmap *altmap;
+ struct page *section_base;
+ struct page *page;
/*
* the section has already be marked as invalid, so
@@ -251,29 +281,33 @@ void __ref vmemmap_free(unsigned long start, unsigned long end)
continue;
addr = vmemmap_list_free(start);
- if (addr) {
- struct page *page = pfn_to_page(addr >> PAGE_SHIFT);
-
- if (PageReserved(page)) {
- /* allocated from bootmem */
- if (page_size < PAGE_SIZE) {
- /*
- * this shouldn't happen, but if it is
- * the case, leave the memory there
- */
- WARN_ON_ONCE(1);
- } else {
- unsigned int nr_pages =
- 1 << get_order(page_size);
- while (nr_pages--)
- free_reserved_page(page++);
- }
- } else
- free_pages((unsigned long)(__va(addr)),
- get_order(page_size));
-
- vmemmap_remove_mapping(start, page_size);
+ if (!addr)
+ continue;
+
+ page = pfn_to_page(addr >> PAGE_SHIFT);
+ section_base = pfn_to_page(vmemmap_section_start(start));
+ nr_pages = 1 << page_order;
+
+ altmap = to_vmem_altmap((unsigned long) section_base);
+ if (altmap) {
+ vmem_altmap_free(altmap, nr_pages);
+ } else if (PageReserved(page)) {
+ /* allocated from bootmem */
+ if (page_size < PAGE_SIZE) {
+ /*
+ * this shouldn't happen, but if it is
+ * the case, leave the memory there
+ */
+ WARN_ON_ONCE(1);
+ } else {
+ while (nr_pages--)
+ free_reserved_page(page++);
+ }
+ } else {
+ free_pages((unsigned long)(__va(addr)), page_order);
}
+
+ vmemmap_remove_mapping(start, page_size);
}
}
#endif