Commit 629ed3f7 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

xtensa/mm/highmem: Switch to generic kmap atomic 



No reason having the same code in every architecture

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201103095858.311016780@linutronix.de
parent 3293efa9

arch/xtensa/Kconfig

+1 −0
Original line number Original line Diff line number Diff line
@@ -666,6 +666,7 @@ endchoice 
config HIGHMEM

config HIGHMEM

	bool "High Memory Support"

	bool "High Memory Support"

	depends on MMU

	depends on MMU

	select KMAP_LOCAL

	help

	help

	  Linux can use the full amount of RAM in the system by

	  Linux can use the full amount of RAM in the system by

	  default. However, the default MMUv2 setup only maps the

	  default. However, the default MMUv2 setup only maps the

arch/xtensa/include/asm/fixmap.h

+2 −2
Original line number Original line Diff line number Diff line
@@ -16,7 +16,7 @@ 
#ifdef CONFIG_HIGHMEM

#ifdef CONFIG_HIGHMEM

#include <linux/threads.h>

#include <linux/threads.h>

#include <linux/pgtable.h>

#include <linux/pgtable.h>

#include <asm/kmap_types.h>

#include <asm/kmap_size.h>

#endif

#endif





/*

/*
@@ -39,7 +39,7 @@ enum fixed_addresses { 
	/* reserved pte's for temporary kernel mappings */

	/* reserved pte's for temporary kernel mappings */

	FIX_KMAP_BEGIN,

	FIX_KMAP_BEGIN,

	FIX_KMAP_END = FIX_KMAP_BEGIN +

	FIX_KMAP_END = FIX_KMAP_BEGIN +

		(KM_TYPE_NR * NR_CPUS * DCACHE_N_COLORS) - 1,

		(KM_MAX_IDX * NR_CPUS * DCACHE_N_COLORS) - 1,

#endif

#endif

	__end_of_fixed_addresses

	__end_of_fixed_addresses

};

};

arch/xtensa/include/asm/highmem.h

+10 −2
Original line number Original line Diff line number Diff line
@@ -16,7 +16,6 @@ 
#include <linux/pgtable.h>

#include <linux/pgtable.h>

#include <asm/cacheflush.h>

#include <asm/cacheflush.h>

#include <asm/fixmap.h>

#include <asm/fixmap.h>

#include <asm/kmap_types.h>





#define PKMAP_BASE		((FIXADDR_START -			\

#define PKMAP_BASE		((FIXADDR_START -			\

				  (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)

				  (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)
@@ -68,6 +67,15 @@ static inline void flush_cache_kmaps(void) 
	flush_cache_all();

	flush_cache_all();

}

}





enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn);

#define arch_kmap_local_map_idx		kmap_local_map_idx



enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr);

#define arch_kmap_local_unmap_idx	kmap_local_unmap_idx



#define arch_kmap_local_post_unmap(vaddr)	\

	local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)



void kmap_init(void);

void kmap_init(void);





#endif
 
#endif

arch/xtensa/mm/highmem.c

+5 −41
Original line number Original line Diff line number Diff line
@@ -12,8 +12,6 @@ 
#include <linux/highmem.h>

#include <linux/highmem.h>

#include <asm/tlbflush.h>

#include <asm/tlbflush.h>





static pte_t *kmap_pte;



#if DCACHE_WAY_SIZE > PAGE_SIZE

#if DCACHE_WAY_SIZE > PAGE_SIZE

unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];

unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];

wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];

wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
@@ -33,59 +31,25 @@ static inline void kmap_waitqueues_init(void) 




static inline enum fixed_addresses kmap_idx(int type, unsigned long color)

static inline enum fixed_addresses kmap_idx(int type, unsigned long color)

{

{

	return (type + KM_TYPE_NR * smp_processor_id()) * DCACHE_N_COLORS +

	return (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS +

		color;

		color;

}

}





void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)

enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn)

{

{

	enum fixed_addresses idx;

	return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT));

	unsigned long vaddr;



	idx = kmap_idx(kmap_atomic_idx_push(),

		       DCACHE_ALIAS(page_to_phys(page)));

	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);

#ifdef CONFIG_DEBUG_HIGHMEM

	BUG_ON(!pte_none(*(kmap_pte + idx)));

#endif

	set_pte(kmap_pte + idx, mk_pte(page, prot));



	return (void *)vaddr;

}

}

EXPORT_SYMBOL(kmap_atomic_high_prot);





void kunmap_atomic_high(void *kvaddr)

enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr)

{

{

	if (kvaddr >= (void *)FIXADDR_START &&

	return kmap_idx(type, DCACHE_ALIAS(addr));

	    kvaddr < (void *)FIXADDR_TOP) {

		int idx = kmap_idx(kmap_atomic_idx(),

				   DCACHE_ALIAS((unsigned long)kvaddr));



		/*

		 * Force other mappings to Oops if they'll try to access this

		 * pte without first remap it.  Keeping stale mappings around

		 * is a bad idea also, in case the page changes cacheability

		 * attributes or becomes a protected page in a hypervisor.

		 */

		pte_clear(&init_mm, kvaddr, kmap_pte + idx);

		local_flush_tlb_kernel_range((unsigned long)kvaddr,

					     (unsigned long)kvaddr + PAGE_SIZE);



		kmap_atomic_idx_pop();

}

}

}

EXPORT_SYMBOL(kunmap_atomic_high);





void __init kmap_init(void)

void __init kmap_init(void)

{

{

	unsigned long kmap_vstart;



	/* Check if this memory layout is broken because PKMAP overlaps

	/* Check if this memory layout is broken because PKMAP overlaps

	 * page table.

	 * page table.

	 */

	 */

	BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);

	BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);

	/* cache the first kmap pte */

	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);

	kmap_pte = virt_to_kpte(kmap_vstart);

	kmap_waitqueues_init();

	kmap_waitqueues_init();

}
 
}