um: decouple MMU specific code from the common part

This splits the memory, process related code with common and MMU
specific parts in order to avoid ifdefs in .c file and duplication
between MMU and !MMU.

Signed-off-by: Hajime Tazaki <thehajime@gmail.com>
[drop many unnecessary changes]
Link: https://patch.msgid.link/20260723113633.af7d6a109c22.Ie82119143778b91fa5585ea3493cf4014113da47@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Hajime Tazaki 2026-07-23 11:35:43 +02:00 committed by Johannes Berg
parent 68885a9445
commit 130031906f
3 changed files with 57 additions and 36 deletions

View File

@ -16,9 +16,10 @@ always-$(KBUILD_BUILTIN) := vmlinux.lds
obj-y = config.o exec.o exitcode.o irq.o ksyms.o mem.o \
physmem.o process.o ptrace.o reboot.o sigio.o \
signal.o sysrq.o time.o tlb.o trap.o \
signal.o sysrq.o time.o trap.o \
um_arch.o umid.o kmsg_dump.o capflags.o skas/
obj-y += load_file.o
obj-$(CONFIG_MMU) += mem-pgtable.o tlb.o
obj-$(CONFIG_BLK_DEV_INITRD) += initrd.o
obj-$(CONFIG_GPROF) += gprof_syms.o

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@ -0,0 +1,55 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
*/
#include <linux/stddef.h>
#include <linux/module.h>
#include <linux/memblock.h>
#include <linux/swap.h>
#include <linux/slab.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <as-layout.h>
#include <init.h>
#include <kern.h>
#include <kern_util.h>
#include <mem_user.h>
#include <os.h>
#include <um_malloc.h>
/* Allocate and free page tables. */
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
if (pgd) {
memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
memcpy(pgd + USER_PTRS_PER_PGD,
swapper_pg_dir + USER_PTRS_PER_PGD,
(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
}
return pgd;
}
static const pgprot_t protection_map[16] = {
[VM_NONE] = PAGE_NONE,
[VM_READ] = PAGE_READONLY,
[VM_WRITE] = PAGE_COPY,
[VM_WRITE | VM_READ] = PAGE_COPY,
[VM_EXEC] = PAGE_READONLY,
[VM_EXEC | VM_READ] = PAGE_READONLY,
[VM_EXEC | VM_WRITE] = PAGE_COPY,
[VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY,
[VM_SHARED] = PAGE_NONE,
[VM_SHARED | VM_READ] = PAGE_READONLY,
[VM_SHARED | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
[VM_SHARED | VM_EXEC] = PAGE_READONLY,
[VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY,
[VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED
};
DECLARE_VM_GET_PAGE_PROT

View File

@ -6,7 +6,6 @@
#include <linux/stddef.h>
#include <linux/module.h>
#include <linux/memblock.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/slab.h>
#include <linux/init.h>
@ -91,45 +90,11 @@ void free_initmem(void)
{
}
/* Allocate and free page tables. */
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd = __pgd_alloc(mm, 0);
if (pgd)
memcpy(pgd + USER_PTRS_PER_PGD,
swapper_pg_dir + USER_PTRS_PER_PGD,
(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
return pgd;
}
void *uml_kmalloc(int size, int flags)
{
return kmalloc(size, flags);
}
static const pgprot_t protection_map[16] = {
[VM_NONE] = PAGE_NONE,
[VM_READ] = PAGE_READONLY,
[VM_WRITE] = PAGE_COPY,
[VM_WRITE | VM_READ] = PAGE_COPY,
[VM_EXEC] = PAGE_READONLY,
[VM_EXEC | VM_READ] = PAGE_READONLY,
[VM_EXEC | VM_WRITE] = PAGE_COPY,
[VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY,
[VM_SHARED] = PAGE_NONE,
[VM_SHARED | VM_READ] = PAGE_READONLY,
[VM_SHARED | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
[VM_SHARED | VM_EXEC] = PAGE_READONLY,
[VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY,
[VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED
};
DECLARE_VM_GET_PAGE_PROT
void mark_rodata_ro(void)
{
unsigned long rodata_start = PFN_ALIGN(__start_rodata);