1 files changed, 53 insertions, 16 deletions

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index f11d1b037c5..354de0763ef 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -95,6 +95,15 @@ struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
 int __initdata memory_end_set;
 unsigned long __initdata memory_end;
 
+unsigned long VMALLOC_START;
+EXPORT_SYMBOL(VMALLOC_START);
+
+unsigned long VMALLOC_END;
+EXPORT_SYMBOL(VMALLOC_END);
+
+struct page *vmemmap;
+EXPORT_SYMBOL(vmemmap);
+
 /* An array with a pointer to the lowcore of every CPU. */
 struct _lowcore *lowcore_ptr[NR_CPUS];
 EXPORT_SYMBOL(lowcore_ptr);
@@ -278,6 +287,15 @@ static int __init early_parse_mem(char *p)
 }
 early_param("mem", early_parse_mem);
 
+static int __init parse_vmalloc(char *arg)
+{
+        if (!arg)
+                return -EINVAL;
+        VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
+        return 0;
+}
+early_param("vmalloc", parse_vmalloc);
+
 unsigned int user_mode = HOME_SPACE_MODE;
 EXPORT_SYMBOL_GPL(user_mode);
 
@@ -383,7 +401,6 @@ setup_lowcore(void)
                 __ctl_set_bit(14, 29);
         }
 #else
-        lc->cmf_hpp = -1ULL;
         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 #endif
         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
@@ -479,8 +496,7 @@ EXPORT_SYMBOL_GPL(real_memory_size);
 
 static void __init setup_memory_end(void)
 {
-        unsigned long memory_size;
-        unsigned long max_mem;
+        unsigned long vmax, vmalloc_size, tmp;
         int i;
 
 
@@ -490,12 +506,9 @@ static void __init setup_memory_end(void)
                 memory_end_set = 1;
         }
 #endif
-        memory_size = 0;
+        real_memory_size = 0;
         memory_end &= PAGE_MASK;
 
-        max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
-        memory_end = min(max_mem, memory_end);
-
         /*
          * Make sure all chunks are MAX_ORDER aligned so we don't need the
          * extra checks that HOLES_IN_ZONE would require.
@@ -515,23 +528,48 @@ static void __init setup_memory_end(void)
                         chunk->addr = start;
                         chunk->size = end - start;
                 }
+                real_memory_size = max(real_memory_size,
+                                       chunk->addr + chunk->size);
         }
 
+        /* Choose kernel address space layout: 2, 3, or 4 levels. */
+#ifdef CONFIG_64BIT
+        vmalloc_size = VMALLOC_END ?: 128UL << 30;
+        tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
+        tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
+        if (tmp <= (1UL << 42))
+                vmax = 1UL << 42;       /* 3-level kernel page table */
+        else
+                vmax = 1UL << 53;       /* 4-level kernel page table */
+#else
+        vmalloc_size = VMALLOC_END ?: 96UL << 20;
+        vmax = 1UL << 31;               /* 2-level kernel page table */
+#endif
+        /* vmalloc area is at the end of the kernel address space. */
+        VMALLOC_END = vmax;
+        VMALLOC_START = vmax - vmalloc_size;
+
+        /* Split remaining virtual space between 1:1 mapping & vmemmap array */
+        tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
+        tmp = VMALLOC_START - tmp * sizeof(struct page);
+        tmp &= ~((vmax >> 11) - 1);     /* align to page table level */
+        tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
+        vmemmap = (struct page *) tmp;
+
+        /* Take care that memory_end is set and <= vmemmap */
+        memory_end = min(memory_end ?: real_memory_size, tmp);
+
+        /* Fixup memory chunk array to fit into 0..memory_end */
         for (i = 0; i < MEMORY_CHUNKS; i++) {
                 struct mem_chunk *chunk = &memory_chunk[i];
 
-                real_memory_size = max(real_memory_size,
-                                       chunk->addr + chunk->size);
-                if (chunk->addr >= max_mem) {
+                if (chunk->addr >= memory_end) {
                         memset(chunk, 0, sizeof(*chunk));
                         continue;
                 }
-                if (chunk->addr + chunk->size > max_mem)
-                        chunk->size = max_mem - chunk->addr;
-                memory_size = max(memory_size, chunk->addr + chunk->size);
+                if (chunk->addr + chunk->size > memory_end)
+                        chunk->size = memory_end - chunk->addr;
         }
-        if (!memory_end)
-                memory_end = memory_size;
 }
 
 void *restart_stack __attribute__((__section__(".data")));
@@ -655,7 +693,6 @@ static int __init verify_crash_base(unsigned long crash_base,
 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
                                          int type)
 {
-
         create_mem_hole(memory_chunk, addr, size, type);
 }