Commit 52d49043 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/mem: flush_dcache_icache_phys() is for HIGHMEM pages only 



__flush_dcache_icache() is usable for non HIGHMEM pages on
every platform.

It is only for HIGHMEM pages that BOOKE needs kmap() and
BOOK3S needs flush_dcache_icache_phys().

So make flush_dcache_icache_phys() dependent on CONFIG_HIGHMEM and
call it only when it is a HIGHMEM page.

We could make flush_dcache_icache_phys() available at all time,
but as it is declared NOKPROBE_SYMBOL(), GCC doesn't optimise
it out when it is not used.

So define a stub for !CONFIG_HIGHMEM in order to remove the #ifdef in
flush_dcache_icache_page() and use IS_ENABLED() instead.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/79ed5d7914f497cd5fcd681ca2f4d50a91719455.1617895813.git.christophe.leroy@csgroup.eu
parent cd97d9e8

arch/powerpc/mm/cacheflush.c

+9 −8
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ void flush_icache_range(unsigned long start, unsigned long stop) 
}

EXPORT_SYMBOL(flush_icache_range);



#if !defined(CONFIG_PPC_8xx) && !defined(CONFIG_PPC64)

#ifdef CONFIG_HIGHMEM

/**

 * flush_dcache_icache_phys() - Flush a page by it's physical address

 * @physaddr: the physical address of the page
@@ -115,7 +115,11 @@ static void flush_dcache_icache_phys(unsigned long physaddr) 
		: "ctr", "memory");

}

NOKPROBE_SYMBOL(flush_dcache_icache_phys)

#endif // !defined(CONFIG_PPC_8xx) && !defined(CONFIG_PPC64)

#else

static void flush_dcache_icache_phys(unsigned long physaddr)

{

}

#endif



/*

 * This is called when a page has been modified by the kernel.
@@ -185,18 +189,15 @@ void flush_dcache_icache_page(struct page *page) 
	if (PageCompound(page))

		return flush_dcache_icache_hugepage(page);



#if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC64)

	/* On 8xx there is no need to kmap since highmem is not supported */

	__flush_dcache_icache(page_address(page));

#else

	if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {

	if (!PageHighMem(page)) {

		__flush_dcache_icache(lowmem_page_address(page));

	} else if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {

		void *start = kmap_atomic(page);

		__flush_dcache_icache(start);

		kunmap_atomic(start);

	} else {

		flush_dcache_icache_phys(page_to_phys(page));

	}

#endif

}

EXPORT_SYMBOL(flush_dcache_icache_page);