[ARM] rationalize memory configuration code some more

Currently there are two instances of struct meminfo: one in
kernel/setup.c marked __initdata, and another in mm/init.c with
permanent storage.  Let's keep only the later to directly populate
the permanent version from arm_add_memory().

Also move common validation tests between the MMU and non-MMU cases
into arm_add_memory() to remove some duplication.  Protection against
overflowing the membank array is also moved in there in order to cover
the kernel cmdline parsing path as well.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 21 insertions, 16 deletions

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 1f1eecca7f55..d21786712c88 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -59,7 +59,7 @@ static int __init fpe_setup(char *line)
 __setup("fpe=", fpe_setup);
 #endif
 
-extern void paging_init(struct meminfo *, struct machine_desc *desc);
+extern void paging_init(struct machine_desc *desc);
 extern void reboot_setup(char *str);
 extern void _text, _etext, __data_start, _edata, _end;
 
@@ -112,7 +112,6 @@ static struct stack stacks[NR_CPUS];
 char elf_platform[ELF_PLATFORM_SIZE];
 EXPORT_SYMBOL(elf_platform);
 
-static struct meminfo meminfo __initdata = { 0, };
 static const char *cpu_name;
 static const char *machine_name;
 static char __initdata command_line[COMMAND_LINE_SIZE];
@@ -367,21 +366,34 @@ static struct machine_desc * __init setup_machine(unsigned int nr)
         return list;
 }
 
-static void __init arm_add_memory(unsigned long start, unsigned long size)
+static int __init arm_add_memory(unsigned long start, unsigned long size)
 {
-        struct membank *bank;
+        struct membank *bank = &meminfo.bank[meminfo.nr_banks];
+
+        if (meminfo.nr_banks >= NR_BANKS) {
+                printk(KERN_CRIT "NR_BANKS too low, "
+                        "ignoring memory at %#lx\n", start);
+                return -EINVAL;
+        }
 
         /*
          * Ensure that start/size are aligned to a page boundary.
          * Size is appropriately rounded down, start is rounded up.
          */
         size -= start & ~PAGE_MASK;
-
-        bank = &meminfo.bank[meminfo.nr_banks++];
-
         bank->start = PAGE_ALIGN(start);
         bank->size  = size & PAGE_MASK;
         bank->node  = PHYS_TO_NID(start);
+
+        /*
+         * Check whether this memory region has non-zero size or
+         * invalid node number.
+         */
+        if (bank->size == 0 || bank->node >= MAX_NUMNODES)
+                return -EINVAL;
+
+        meminfo.nr_banks++;
+        return 0;
 }
 
 /*
@@ -539,14 +551,7 @@ __tagtable(ATAG_CORE, parse_tag_core);
 
 static int __init parse_tag_mem32(const struct tag *tag)
 {
-        if (meminfo.nr_banks >= NR_BANKS) {
-                printk(KERN_WARNING
-                       "Ignoring memory bank 0x%08x size %dKB\n",
-                        tag->u.mem.start, tag->u.mem.size / 1024);
-                return -EINVAL;
-        }
-        arm_add_memory(tag->u.mem.start, tag->u.mem.size);
-        return 0;
+        return arm_add_memory(tag->u.mem.start, tag->u.mem.size);
 }
 
 __tagtable(ATAG_MEM, parse_tag_mem32);
@@ -718,7 +723,7 @@ void __init setup_arch(char **cmdline_p)
         memcpy(boot_command_line, from, COMMAND_LINE_SIZE);
         boot_command_line[COMMAND_LINE_SIZE-1] = '\0';
         parse_cmdline(cmdline_p, from);
-        paging_init(&meminfo, mdesc);
+        paging_init(mdesc);
         request_standard_resources(&meminfo, mdesc);
 
 #ifdef CONFIG_SMP