Unverified Commit 63bb76de authored by Pekka Enberg's avatar Pekka Enberg Committed by Palmer Dabbelt
Browse files

mm: pgtable: Make generic pgprot_* macros available for no-MMU 



The <linux/pgtable.h> header defines some generic pgprot_*
implementations, but they are only available when CONFIG_MMU is enabled.
The RISC-V architecture, for example, therefore defines some of these
pgprot_* macros for !NOMMU.

Let's make the pgprot_* generic available even for !NOMMU so we can
remove the RISC-V specific definitions.

Compile-tested with x86 defconfig, and riscv defconfig and !MMU defconfig.

Suggested-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: default avatarMike Rapoport <rppt@linux.ibm.com>
Acked-by: default avatarDavid Rientjes <rientjes@google.com>
Signed-off-by: default avatarPekka Enberg <penberg@kernel.org>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent 3e7b669c

include/linux/pgtable.h

+37 −34
Original line number Diff line number Diff line
@@ -647,40 +647,6 @@ static inline int arch_unmap_one(struct mm_struct *mm, 
#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)

#endif



#ifndef pgprot_nx

#define pgprot_nx(prot)	(prot)

#endif



#ifndef pgprot_noncached

#define pgprot_noncached(prot)	(prot)

#endif



#ifndef pgprot_writecombine

#define pgprot_writecombine pgprot_noncached

#endif



#ifndef pgprot_writethrough

#define pgprot_writethrough pgprot_noncached

#endif



#ifndef pgprot_device

#define pgprot_device pgprot_noncached

#endif



#ifndef pgprot_modify

#define pgprot_modify pgprot_modify

static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)

{

	if (pgprot_val(oldprot) == pgprot_val(pgprot_noncached(oldprot)))

		newprot = pgprot_noncached(newprot);

	if (pgprot_val(oldprot) == pgprot_val(pgprot_writecombine(oldprot)))

		newprot = pgprot_writecombine(newprot);

	if (pgprot_val(oldprot) == pgprot_val(pgprot_device(oldprot)))

		newprot = pgprot_device(newprot);

	return newprot;

}

#endif



/*

 * When walking page tables, get the address of the next boundary,

 * or the end address of the range if that comes earlier.  Although no
@@ -840,6 +806,43 @@ static inline void ptep_modify_prot_commit(struct vm_area_struct *vma, 
 * No-op macros that just return the current protection value. Defined here

 * because these macros can be used used even if CONFIG_MMU is not defined.

 */



#ifndef pgprot_nx

#define pgprot_nx(prot)	(prot)

#endif



#ifndef pgprot_noncached

#define pgprot_noncached(prot)	(prot)

#endif



#ifndef pgprot_writecombine

#define pgprot_writecombine pgprot_noncached

#endif



#ifndef pgprot_writethrough

#define pgprot_writethrough pgprot_noncached

#endif



#ifndef pgprot_device

#define pgprot_device pgprot_noncached

#endif



#ifdef CONFIG_MMU

#ifndef pgprot_modify

#define pgprot_modify pgprot_modify

static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)

{

	if (pgprot_val(oldprot) == pgprot_val(pgprot_noncached(oldprot)))

		newprot = pgprot_noncached(newprot);

	if (pgprot_val(oldprot) == pgprot_val(pgprot_writecombine(oldprot)))

		newprot = pgprot_writecombine(newprot);

	if (pgprot_val(oldprot) == pgprot_val(pgprot_device(oldprot)))

		newprot = pgprot_device(newprot);

	return newprot;

}

#endif

#endif /* CONFIG_MMU */



#ifndef pgprot_encrypted

#define pgprot_encrypted(prot)	(prot)

#endif

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