powerpc: function to allocate gigantic hugepages
The 16G page locations have been saved during early boot in an array. The
alloc_bootmem_huge_page() function adds a page from here to the
huge_boot_pages list.
Acked-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 63db7ad..5df8218 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -29,6 +29,12 @@
#define NUM_LOW_AREAS (0x100000000UL >> SID_SHIFT)
#define NUM_HIGH_AREAS (PGTABLE_RANGE >> HTLB_AREA_SHIFT)
+#define MAX_NUMBER_GPAGES 1024
+
+/* Tracks the 16G pages after the device tree is scanned and before the
+ * huge_boot_pages list is ready. */
+static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
+static unsigned nr_gpages;
unsigned int hugepte_shift;
#define PTRS_PER_HUGEPTE (1 << hugepte_shift)
@@ -104,6 +110,21 @@
}
#endif
+/* Moves the gigantic page addresses from the temporary list to the
+ * huge_boot_pages list. */
+int alloc_bootmem_huge_page(struct hstate *h)
+{
+ struct huge_bootmem_page *m;
+ if (nr_gpages == 0)
+ return 0;
+ m = phys_to_virt(gpage_freearray[--nr_gpages]);
+ gpage_freearray[nr_gpages] = 0;
+ list_add(&m->list, &huge_boot_pages);
+ m->hstate = h;
+ return 1;
+}
+
+
/* Modelled after find_linux_pte() */
pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{