Commit 873ba463 authored by Mike Rapoport's avatar Mike Rapoport Committed by Linus Torvalds
Browse files

arm64: decouple check whether pfn is in linear map from pfn_valid() 

The intended semantics of pfn_valid() is to verify whether there is a
struct page for the pfn in question and nothing else.

Yet, on arm64 it is used to distinguish memory areas that are mapped in
the linear map vs those that require ioremap() to access them.

Introduce a dedicated pfn_is_map_memory() wrapper for
memblock_is_map_memory() to perform such check and use it where
appropriate.

Using a wrapper allows to avoid cyclic include dependencies.

While here also update style of pfn_valid() so that both pfn_valid() and
pfn_is_map_memory() declarations will be consistent.

Link: https://lkml.kernel.org/r/20210511100550.28178-4-rppt@kernel.org


Signed-off-by: default avatarMike Rapoport <rppt@linux.ibm.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Acked-by: default avatarArd Biesheuvel <ardb@kernel.org>
Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 9092d4f7

arch/arm64/include/asm/memory.h

+1 −1
Original line number Diff line number Diff line
@@ -369,7 +369,7 @@ static inline void *phys_to_virt(phys_addr_t x) 


#define virt_addr_valid(addr)	({					\

	__typeof__(addr) __addr = __tag_reset(addr);			\

	__is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr));	\

	__is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr));	\

})



void dump_mem_limit(void);

arch/arm64/include/asm/page.h

+2 −1
Original line number Diff line number Diff line
@@ -37,7 +37,8 @@ void copy_highpage(struct page *to, struct page *from); 


typedef struct page *pgtable_t;



extern int pfn_valid(unsigned long);

int pfn_valid(unsigned long pfn);

int pfn_is_map_memory(unsigned long pfn);



#include <asm/memory.h>

arch/arm64/kvm/mmu.c

+1 −1
Original line number Diff line number Diff line
@@ -85,7 +85,7 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) 


static bool kvm_is_device_pfn(unsigned long pfn)

{

	return !pfn_valid(pfn);

	return !pfn_is_map_memory(pfn);

}



static void *stage2_memcache_zalloc_page(void *arg)

arch/arm64/mm/init.c

+12 −0
Original line number Diff line number Diff line
@@ -256,6 +256,18 @@ int pfn_valid(unsigned long pfn) 
}

EXPORT_SYMBOL(pfn_valid);



int pfn_is_map_memory(unsigned long pfn)

{

	phys_addr_t addr = PFN_PHYS(pfn);



	/* avoid false positives for bogus PFNs, see comment in pfn_valid() */

	if (PHYS_PFN(addr) != pfn)

		return 0;



	return memblock_is_map_memory(addr);

}

EXPORT_SYMBOL(pfn_is_map_memory);



static phys_addr_t memory_limit = PHYS_ADDR_MAX;



/*

arch/arm64/mm/ioremap.c

+2 −2
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size, 
	/*

	 * Don't allow RAM to be mapped.

	 */

	if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))

	if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr))))

		return NULL;



	area = get_vm_area_caller(size, VM_IOREMAP, caller);
@@ -84,7 +84,7 @@ EXPORT_SYMBOL(iounmap); 
void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)

{

	/* For normal memory we already have a cacheable mapping. */

	if (pfn_valid(__phys_to_pfn(phys_addr)))

	if (pfn_is_map_memory(__phys_to_pfn(phys_addr)))

		return (void __iomem *)__phys_to_virt(phys_addr);



	return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),