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, 9 insertions, 8 deletions

diff --git a/kernel/module/kdb.c b/kernel/module/kdb.c
index f4317f92e189..995c32d3698f 100644
--- a/kernel/module/kdb.c
+++ b/kernel/module/kdb.c
@@ -26,10 +26,11 @@ int kdb_lsmod(int argc, const char **argv)
 		if (mod->state == MODULE_STATE_UNFORMED)
 			continue;
 
-		kdb_printf("%-20s%8u", mod->name, mod->core_layout.size);
-#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
-		kdb_printf("/%8u", mod->data_layout.size);
-#endif
+		kdb_printf("%-20s%8u", mod->name, mod->mem[MOD_TEXT].size);
+		kdb_printf("/%8u", mod->mem[MOD_RODATA].size);
+		kdb_printf("/%8u", mod->mem[MOD_RO_AFTER_INIT].size);
+		kdb_printf("/%8u", mod->mem[MOD_DATA].size);
+
 		kdb_printf("  0x%px ", (void *)mod);
 #ifdef CONFIG_MODULE_UNLOAD
 		kdb_printf("%4d ", module_refcount(mod));
@@ -40,10 +41,10 @@ int kdb_lsmod(int argc, const char **argv)
 			kdb_printf(" (Loading)");
 		else
 			kdb_printf(" (Live)");
-		kdb_printf(" 0x%px", mod->core_layout.base);
-#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
-		kdb_printf("/0x%px", mod->data_layout.base);
-#endif
+		kdb_printf(" 0x%px", mod->mem[MOD_TEXT].base);
+		kdb_printf("/0x%px", mod->mem[MOD_RODATA].base);
+		kdb_printf("/0x%px", mod->mem[MOD_RO_AFTER_INIT].base);
+		kdb_printf("/0x%px", mod->mem[MOD_DATA].base);
 
 #ifdef CONFIG_MODULE_UNLOAD
 		{