Commit af86e597 authored by Laura Abbott's avatar Laura Abbott Committed by Will Deacon
Browse files

arm64: Factor out fixmap initialization from ioremap 



The fixmap API was originally added for arm64 for
early_ioremap purposes. It can be used for other purposes too
so move the initialization from ioremap to somewhere more
generic. This makes it obvious where the fixmap is being set
up and allows for a cleaner implementation of __set_fixmap.

Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
Tested-by: default avatarMark Rutland <mark.rutland@arm.com>
Tested-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent c3684fbb

arch/arm64/include/asm/fixmap.h

+4 −3
Original line number Diff line number Diff line
@@ -56,10 +56,11 @@ enum fixed_addresses { 


#define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)



extern void __early_set_fixmap(enum fixed_addresses idx,

			       phys_addr_t phys, pgprot_t flags);

void __init early_fixmap_init(void);



#define __set_fixmap __early_set_fixmap

#define __early_set_fixmap __set_fixmap



extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);



#include <asm-generic/fixmap.h>

arch/arm64/kernel/setup.c

+1 −0
Original line number Diff line number Diff line
@@ -384,6 +384,7 @@ void __init setup_arch(char **cmdline_p) 


	*cmdline_p = boot_command_line;



	early_fixmap_init();

	early_ioremap_init();



	parse_early_param();

arch/arm64/mm/ioremap.c

+3 −90
Original line number Diff line number Diff line
@@ -103,97 +103,10 @@ void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size) 
}

EXPORT_SYMBOL(ioremap_cache);



static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;

#if CONFIG_ARM64_PGTABLE_LEVELS > 2

static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss;

#endif

#if CONFIG_ARM64_PGTABLE_LEVELS > 3

static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss;

#endif



static inline pud_t * __init early_ioremap_pud(unsigned long addr)

{

	pgd_t *pgd;



	pgd = pgd_offset_k(addr);

	BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd));



	return pud_offset(pgd, addr);

}



static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)

{

	pud_t *pud = early_ioremap_pud(addr);



	BUG_ON(pud_none(*pud) || pud_bad(*pud));



	return pmd_offset(pud, addr);

}



static inline pte_t * __init early_ioremap_pte(unsigned long addr)

{

	pmd_t *pmd = early_ioremap_pmd(addr);



	BUG_ON(pmd_none(*pmd) || pmd_bad(*pmd));



	return pte_offset_kernel(pmd, addr);

}



void __init early_ioremap_init(void)

{

	pgd_t *pgd;

	pud_t *pud;

	pmd_t *pmd;

	unsigned long addr = fix_to_virt(FIX_BTMAP_BEGIN);



	pgd = pgd_offset_k(addr);

	pgd_populate(&init_mm, pgd, bm_pud);

	pud = pud_offset(pgd, addr);

	pud_populate(&init_mm, pud, bm_pmd);

	pmd = pmd_offset(pud, addr);

	pmd_populate_kernel(&init_mm, pmd, bm_pte);



/*

	 * The boot-ioremap range spans multiple pmds, for which

	 * we are not prepared:

 * Must be called after early_fixmap_init

 */

	BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)

		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));



	if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {

		WARN_ON(1);

		pr_warn("pmd %p != %p\n",

			pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));

		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",

			fix_to_virt(FIX_BTMAP_BEGIN));

		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",

			fix_to_virt(FIX_BTMAP_END));



		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);

		pr_warn("FIX_BTMAP_BEGIN:     %d\n",

			FIX_BTMAP_BEGIN);

	}



	early_ioremap_setup();

}



void __init __early_set_fixmap(enum fixed_addresses idx,

			       phys_addr_t phys, pgprot_t flags)

void __init early_ioremap_init(void)

{

	unsigned long addr = __fix_to_virt(idx);

	pte_t *pte;



	if (idx >= __end_of_fixed_addresses) {

		BUG();

		return;

	}



	pte = early_ioremap_pte(addr);



	if (pgprot_val(flags))

		set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));

	else {

		pte_clear(&init_mm, addr, pte);

		flush_tlb_kernel_range(addr, addr+PAGE_SIZE);

	}

	early_ioremap_setup();

}

arch/arm64/mm/mmu.c

+94 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
#include <linux/io.h>



#include <asm/cputype.h>

#include <asm/fixmap.h>

#include <asm/sections.h>

#include <asm/setup.h>

#include <asm/sizes.h>
@@ -463,3 +464,96 @@ void vmemmap_free(unsigned long start, unsigned long end) 
{

}

#endif	/* CONFIG_SPARSEMEM_VMEMMAP */



static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;

#if CONFIG_ARM64_PGTABLE_LEVELS > 2

static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss;

#endif

#if CONFIG_ARM64_PGTABLE_LEVELS > 3

static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss;

#endif



static inline pud_t * fixmap_pud(unsigned long addr)

{

	pgd_t *pgd = pgd_offset_k(addr);



	BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd));



	return pud_offset(pgd, addr);

}



static inline pmd_t * fixmap_pmd(unsigned long addr)

{

	pud_t *pud = fixmap_pud(addr);



	BUG_ON(pud_none(*pud) || pud_bad(*pud));



	return pmd_offset(pud, addr);

}



static inline pte_t * fixmap_pte(unsigned long addr)

{

	pmd_t *pmd = fixmap_pmd(addr);



	BUG_ON(pmd_none(*pmd) || pmd_bad(*pmd));



	return pte_offset_kernel(pmd, addr);

}



void __init early_fixmap_init(void)

{

	pgd_t *pgd;

	pud_t *pud;

	pmd_t *pmd;

	unsigned long addr = FIXADDR_START;



	pgd = pgd_offset_k(addr);

	pgd_populate(&init_mm, pgd, bm_pud);

	pud = pud_offset(pgd, addr);

	pud_populate(&init_mm, pud, bm_pmd);

	pmd = pmd_offset(pud, addr);

	pmd_populate_kernel(&init_mm, pmd, bm_pte);



	/*

	 * The boot-ioremap range spans multiple pmds, for which

	 * we are not preparted:

	 */

	BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)

		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));



	if ((pmd != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)))

	     || pmd != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) {

		WARN_ON(1);

		pr_warn("pmd %p != %p, %p\n",

			pmd, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)),

			fixmap_pmd(fix_to_virt(FIX_BTMAP_END)));

		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",

			fix_to_virt(FIX_BTMAP_BEGIN));

		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",

			fix_to_virt(FIX_BTMAP_END));



		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);

		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);

	}

}



void __set_fixmap(enum fixed_addresses idx,

			       phys_addr_t phys, pgprot_t flags)

{

	unsigned long addr = __fix_to_virt(idx);

	pte_t *pte;



	if (idx >= __end_of_fixed_addresses) {

		BUG();

		return;

	}



	pte = fixmap_pte(addr);



	if (pgprot_val(flags)) {

		set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));

	} else {

		pte_clear(&init_mm, addr, pte);

		flush_tlb_kernel_range(addr, addr+PAGE_SIZE);

	}

}

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