Commit ccfbc68d authored by Sven Schnelle's avatar Sven Schnelle Committed by Helge Deller
Browse files

parisc: add set_fixmap()/clear_fixmap() 



These functions will be used for adding code patching
functions later.

Signed-off-by: default avatarSven Schnelle <svens@stackframe.org>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 17d9822d

arch/parisc/include/asm/fixmap.h

+18 −1
Original line number Diff line number Diff line
@@ -15,17 +15,34 @@ 
 * from areas congruently mapped with user space.  It is 8MB large

 * and must be 16MB aligned */

#define TMPALIAS_MAP_START	((__PAGE_OFFSET) - 16*1024*1024)



#define FIXMAP_SIZE		(FIX_BITMAP_COUNT << PAGE_SHIFT)

#define FIXMAP_START		(TMPALIAS_MAP_START - FIXMAP_SIZE)

/* This is the kernel area for all maps (vmalloc, dma etc.)  most

 * usually, it extends up to TMPALIAS_MAP_START.  Virtual addresses

 * 0..GATEWAY_PAGE_SIZE are reserved for the gateway page */

#define KERNEL_MAP_START	(GATEWAY_PAGE_SIZE)

#define KERNEL_MAP_END		(TMPALIAS_MAP_START)

#define KERNEL_MAP_END		(FIXMAP_START)



#ifndef __ASSEMBLY__





enum fixed_addresses {

	/* Support writing RO kernel text via kprobes, jump labels, etc. */

	FIX_TEXT_POKE0,

	FIX_BITMAP_COUNT

};



extern void *parisc_vmalloc_start;

#define PCXL_DMA_MAP_SIZE	(8*1024*1024)

#define VMALLOC_START		((unsigned long)parisc_vmalloc_start)

#define VMALLOC_END		(KERNEL_MAP_END)



#define __fix_to_virt(_x) (FIXMAP_START + ((_x) << PAGE_SHIFT))



void set_fixmap(enum fixed_addresses idx, phys_addr_t phys);

void clear_fixmap(enum fixed_addresses idx);



#endif /*__ASSEMBLY__*/



#endif /*_ASM_FIXMAP_H*/

arch/parisc/mm/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -2,5 +2,5 @@ 
# Makefile for arch/parisc/mm

#



obj-y	 := init.o fault.o ioremap.o

obj-y	 := init.o fault.o ioremap.o fixmap.o

obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o

arch/parisc/mm/fixmap.c

0 → 100644
+41 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * fixmaps for parisc

 *

 * Copyright (c) 2019 Sven Schnelle <svens@stackframe.org>

 */



#include <linux/kprobes.h>

#include <linux/mm.h>

#include <asm/cacheflush.h>

#include <asm/fixmap.h>



void set_fixmap(enum fixed_addresses idx, phys_addr_t phys)

{

	unsigned long vaddr = __fix_to_virt(idx);

	pgd_t *pgd = pgd_offset_k(vaddr);

	pmd_t *pmd = pmd_offset(pgd, vaddr);

	pte_t *pte;



	if (pmd_none(*pmd))

		pmd = pmd_alloc(NULL, pgd, vaddr);



	pte = pte_offset_kernel(pmd, vaddr);

	if (pte_none(*pte))

		pte = pte_alloc_kernel(pmd, vaddr);



	set_pte_at(&init_mm, vaddr, pte, __mk_pte(phys, PAGE_KERNEL_RWX));

	flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);

}



void clear_fixmap(enum fixed_addresses idx)

{

	unsigned long vaddr = __fix_to_virt(idx);

	pgd_t *pgd = pgd_offset_k(vaddr);

	pmd_t *pmd = pmd_offset(pgd, vaddr);

	pte_t *pte = pte_offset_kernel(pmd, vaddr);



	pte_clear(&init_mm, vaddr, pte);



	flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);

}

arch/parisc/mm/init.c

+9 −5
Original line number Diff line number Diff line
@@ -623,6 +623,7 @@ void __init mem_init(void) 
	 */

	printk("virtual kernel memory layout:\n"

	       "     vmalloc : 0x%px - 0x%px   (%4ld MB)\n"

	       "     fixmap  : 0x%px - 0x%px   (%4ld kB)\n"

	       "     memory  : 0x%px - 0x%px   (%4ld MB)\n"

	       "       .init : 0x%px - 0x%px   (%4ld kB)\n"

	       "       .data : 0x%px - 0x%px   (%4ld kB)\n"
@@ -631,6 +632,9 @@ void __init mem_init(void) 
	       (void*)VMALLOC_START, (void*)VMALLOC_END,

	       (VMALLOC_END - VMALLOC_START) >> 20,



	       (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),

	       (unsigned long)(FIXMAP_SIZE / 1024),



	       __va(0), high_memory,

	       ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,