module: replace module_layout with module_memory

module_layout manages different types of memory (text, data, rodata, etc.)
in one allocation, which is problematic for some reasons:

1. It is hard to enable CONFIG_STRICT_MODULE_RWX.
2. It is hard to use huge pages in modules (and not break strict rwx).
3. Many archs uses module_layout for arch-specific data, but it is not
   obvious how these data are used (are they RO, RX, or RW?)

Improve the scenario by replacing 2 (or 3) module_layout per module with
up to 7 module_memory per module:

        MOD_TEXT,
        MOD_DATA,
        MOD_RODATA,
        MOD_RO_AFTER_INIT,
        MOD_INIT_TEXT,
        MOD_INIT_DATA,
        MOD_INIT_RODATA,

and allocating them separately. This adds slightly more entries to
mod_tree (from up to 3 entries per module, to up to 7 entries per
module). However, this at most adds a small constant overhead to
__module_address(), which is expected to be fast.

Various archs use module_layout for different data. These data are put
into different module_memory based on their location in module_layout.
IOW, data that used to go with text is allocated with MOD_MEM_TYPE_TEXT;
data that used to go with data is allocated with MOD_MEM_TYPE_DATA, etc.

module_memory simplifies quite some of the module code. For example,
ARCH_WANTS_MODULES_DATA_IN_VMALLOC is a lot cleaner, as it just uses a
different allocator for the data. kernel/module/strict_rwx.c is also
much cleaner with module_memory.

Signed-off-by: Song Liu <song@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

1 files changed, 11 insertions, 5 deletions

diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c
index cf5b9f1e6ec4..0a4841e88adb 100644
--- a/kernel/module/procfs.c
+++ b/kernel/module/procfs.c
@@ -62,6 +62,15 @@ static void m_stop(struct seq_file *m, void *p)
 	mutex_unlock(&module_mutex);
 }
 
+static unsigned int module_total_size(struct module *mod)
+{
+	int size = 0;
+
+	for_each_mod_mem_type(type)
+		size += mod->mem[type].size;
+	return size;
+}
+
 static int m_show(struct seq_file *m, void *p)
 {
 	struct module *mod = list_entry(p, struct module, list);
@@ -73,10 +82,7 @@ static int m_show(struct seq_file *m, void *p)
 	if (mod->state == MODULE_STATE_UNFORMED)
 		return 0;
 
-	size = mod->init_layout.size + mod->core_layout.size;
-#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
-	size += mod->data_layout.size;
-#endif
+	size = module_total_size(mod);
 	seq_printf(m, "%s %u", mod->name, size);
 	print_unload_info(m, mod);
 
@@ -86,7 +92,7 @@ static int m_show(struct seq_file *m, void *p)
 		   mod->state == MODULE_STATE_COMING ? "Loading" :
 		   "Live");
 	/* Used by oprofile and other similar tools. */
-	value = m->private ? NULL : mod->core_layout.base;
+	value = m->private ? NULL : mod->mem[MOD_TEXT].base;
 	seq_printf(m, " 0x%px", value);
 
 	/* Taints info */