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Diffstat (limited to 'arch/powerpc/mm/mem.c')
-rw-r--r--arch/powerpc/mm/mem.c68
1 files changed, 62 insertions, 6 deletions
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index e0f7a189c48e..8ebaac75c940 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -260,6 +260,60 @@ static int __init mark_nonram_nosave(void)
}
return 0;
}
+#else /* CONFIG_NEED_MULTIPLE_NODES */
+static int __init mark_nonram_nosave(void)
+{
+ return 0;
+}
+#endif
+
+static bool zone_limits_final;
+
+static unsigned long max_zone_pfns[MAX_NR_ZONES] = {
+ [0 ... MAX_NR_ZONES - 1] = ~0UL
+};
+
+/*
+ * Restrict the specified zone and all more restrictive zones
+ * to be below the specified pfn. May not be called after
+ * paging_init().
+ */
+void __init limit_zone_pfn(enum zone_type zone, unsigned long pfn_limit)
+{
+ int i;
+
+ if (WARN_ON(zone_limits_final))
+ return;
+
+ for (i = zone; i >= 0; i--) {
+ if (max_zone_pfns[i] > pfn_limit)
+ max_zone_pfns[i] = pfn_limit;
+ }
+}
+
+/*
+ * Find the least restrictive zone that is entirely below the
+ * specified pfn limit. Returns < 0 if no suitable zone is found.
+ *
+ * pfn_limit must be u64 because it can exceed 32 bits even on 32-bit
+ * systems -- the DMA limit can be higher than any possible real pfn.
+ */
+int dma_pfn_limit_to_zone(u64 pfn_limit)
+{
+ enum zone_type top_zone = ZONE_NORMAL;
+ int i;
+
+#ifdef CONFIG_HIGHMEM
+ top_zone = ZONE_HIGHMEM;
+#endif
+
+ for (i = top_zone; i >= 0; i--) {
+ if (max_zone_pfns[i] <= pfn_limit)
+ return i;
+ }
+
+ return -EPERM;
+}
/*
* paging_init() sets up the page tables - in fact we've already done this.
@@ -268,7 +322,7 @@ void __init paging_init(void)
{
unsigned long long total_ram = memblock_phys_mem_size();
phys_addr_t top_of_ram = memblock_end_of_DRAM();
- unsigned long max_zone_pfns[MAX_NR_ZONES];
+ enum zone_type top_zone;
#ifdef CONFIG_PPC32
unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
@@ -290,18 +344,20 @@ void __init paging_init(void)
(unsigned long long)top_of_ram, total_ram);
printk(KERN_DEBUG "Memory hole size: %ldMB\n",
(long int)((top_of_ram - total_ram) >> 20));
- memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+
#ifdef CONFIG_HIGHMEM
- max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
- max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
+ top_zone = ZONE_HIGHMEM;
+ limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT);
#else
- max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
+ top_zone = ZONE_NORMAL;
#endif
+
+ limit_zone_pfn(top_zone, top_of_ram >> PAGE_SHIFT);
+ zone_limits_final = true;
free_area_init_nodes(max_zone_pfns);
mark_nonram_nosave();
}
-#endif /* ! CONFIG_NEED_MULTIPLE_NODES */
static void __init register_page_bootmem_info(void)
{