Le 07/12/2022 à 16:36, Thomas Gleixner a écrit :
>
> The "use free space in existing mappings" mechanism is not required to
> be PMD_SIZE based, right?
>
> Large page size, strict separation:
>
> struct mod_alloc_type_params {
> [MOD_ALLOC_TYPE_TEXT] = {
> .mapto_type = MOD_ALLOC_TYPE_TEXT,
> .flags = FLAG_SHARED_PMD | FLAG_SECOND_ADDRESS_SPACE,
> .granularity = PMD_SIZE,
> .alignment = MOD_ARCH_ALIGNMENT,
> .start[0] = MODULES_VADDR,
> .end[0] = MODULES_END,
> .start[1] = MODULES_VADDR_2ND,
> .end[1] = MODULES_END_2ND,
> .pgprot = PAGE_KERNEL_EXEC,
> .fill = text_poke,
> .invalidate = text_poke_invalidate,
> },
Don't restrict implementation to PMD_SIZE only.
On powerpc 8xx:
- PMD_SIZE is 4 Mbytes
- Large pages are 512 kbytes and 8 Mbytes.
It even has large pages of size 16 kbytes when build for 4k normal page
size.
Christophe
