Commit 06dfae39 authored by Baoquan He's avatar Baoquan He Committed by Andrew Morton
Browse files

arc: mm: convert to GENERIC_IOREMAP 

By taking GENERIC_IOREMAP method, the generic generic_ioremap_prot(),
generic_iounmap(), and their generic wrapper ioremap_prot(), ioremap() and
iounmap() are all visible and available to arch.  Arch needs to provide
wrapper functions to override the generic versions if there's arch
specific handling in its ioremap_prot(), ioremap() or iounmap().  This
change will simplify implementation by removing duplicated code with
generic_ioremap_prot() and generic_iounmap(), and has the equivalent
functioality as before.

Here, add wrapper functions ioremap_prot() and iounmap() for arc's special
operation when ioremap_prot() and iounmap().

Link: https://lkml.kernel.org/r/20230706154520.11257-8-bhe@redhat.com


Signed-off-by: default avatarBaoquan He <bhe@redhat.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMike Rapoport (IBM) <rppt@kernel.org>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent a5f61648

arch/arc/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ config ARC 
	select GENERIC_PENDING_IRQ if SMP

	select GENERIC_SCHED_CLOCK

	select GENERIC_SMP_IDLE_THREAD

	select GENERIC_IOREMAP

	select HAVE_ARCH_KGDB

	select HAVE_ARCH_TRACEHOOK

	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARC_MMU_V4

arch/arc/include/asm/io.h

+3 −4
Original line number Diff line number Diff line
@@ -21,8 +21,9 @@ 
#endif



extern void __iomem *ioremap(phys_addr_t paddr, unsigned long size);

extern void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,

				  unsigned long flags);

#define ioremap ioremap

#define ioremap_prot ioremap_prot

#define iounmap iounmap

static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)

{

	return (void __iomem *)port;
@@ -32,8 +33,6 @@ static inline void ioport_unmap(void __iomem *addr) 
{

}



extern void iounmap(const volatile void __iomem *addr);



/*

 * io{read,write}{16,32}be() macros

 */

arch/arc/mm/ioremap.c

+4 −45
Original line number Diff line number Diff line
@@ -8,7 +8,6 @@ 
#include <linux/module.h>

#include <linux/io.h>

#include <linux/mm.h>

#include <linux/slab.h>

#include <linux/cache.h>



static inline bool arc_uncached_addr_space(phys_addr_t paddr)
@@ -25,13 +24,6 @@ static inline bool arc_uncached_addr_space(phys_addr_t paddr) 


void __iomem *ioremap(phys_addr_t paddr, unsigned long size)

{

	phys_addr_t end;



	/* Don't allow wraparound or zero size */

	end = paddr + size - 1;

	if (!size || (end < paddr))

		return NULL;



	/*

	 * If the region is h/w uncached, MMU mapping can be elided as optim

	 * The cast to u32 is fine as this region can only be inside 4GB
@@ -51,55 +43,22 @@ EXPORT_SYMBOL(ioremap); 
 * ARC hardware uncached region, this one still goes thru the MMU as caller

 * might need finer access control (R/W/X)

 */

void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,

void __iomem *ioremap_prot(phys_addr_t paddr, size_t size,

			   unsigned long flags)

{

	unsigned int off;

	unsigned long vaddr;

	struct vm_struct *area;

	phys_addr_t end;

	pgprot_t prot = __pgprot(flags);



	/* Don't allow wraparound, zero size */

	end = paddr + size - 1;

	if ((!size) || (end < paddr))

		return NULL;



	/* An early platform driver might end up here */

	if (!slab_is_available())

		return NULL;



	/* force uncached */

	prot = pgprot_noncached(prot);



	/* Mappings have to be page-aligned */

	off = paddr & ~PAGE_MASK;

	paddr &= PAGE_MASK_PHYS;

	size = PAGE_ALIGN(end + 1) - paddr;



	/*

	 * Ok, go for it..

	 */

	area = get_vm_area(size, VM_IOREMAP);

	if (!area)

		return NULL;

	area->phys_addr = paddr;

	vaddr = (unsigned long)area->addr;

	if (ioremap_page_range(vaddr, vaddr + size, paddr, prot)) {

		vunmap((void __force *)vaddr);

		return NULL;

	}

	return (void __iomem *)(off + (char __iomem *)vaddr);

	return generic_ioremap_prot(paddr, size, pgprot_noncached(prot));

}

EXPORT_SYMBOL(ioremap_prot);





void iounmap(const volatile void __iomem *addr)

void iounmap(volatile void __iomem *addr)

{

	/* weird double cast to handle phys_addr_t > 32 bits */

	if (arc_uncached_addr_space((phys_addr_t)(u32)addr))

		return;



	vfree((void *)(PAGE_MASK & (unsigned long __force)addr));

	generic_iounmap(addr);

}

EXPORT_SYMBOL(iounmap);