linux/mm/ioremap.c
Baoquan He dfdc6ba957 mm: ioremap: allow ARCH to have its own ioremap method definition
Architectures can be converted to GENERIC_IOREMAP, to take standard
ioremap_xxx() and iounmap() way.  But some ARCH-es could have specific
handling for ioremap_prot(), ioremap() and iounmap(), than standard
methods.

In oder to convert these ARCH-es to take GENERIC_IOREMAP method, allow
these architecutres to have their own ioremap_prot(), ioremap() and
iounmap() definitions.

Link: https://lkml.kernel.org/r/20230706154520.11257-6-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
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: 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: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:12:33 -07:00

76 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Re-map IO memory to kernel address space so that we can access it.
* This is needed for high PCI addresses that aren't mapped in the
* 640k-1MB IO memory area on PC's
*
* (C) Copyright 1995 1996 Linus Torvalds
*/
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/export.h>
void __iomem *generic_ioremap_prot(phys_addr_t phys_addr, size_t size,
pgprot_t prot)
{
unsigned long offset, vaddr;
phys_addr_t last_addr;
struct vm_struct *area;
/* Disallow wrap-around or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/* Page-align mappings */
offset = phys_addr & (~PAGE_MASK);
phys_addr -= offset;
size = PAGE_ALIGN(size + offset);
if (!ioremap_allowed(phys_addr, size, pgprot_val(prot)))
return NULL;
area = get_vm_area_caller(size, VM_IOREMAP,
__builtin_return_address(0));
if (!area)
return NULL;
vaddr = (unsigned long)area->addr;
area->phys_addr = phys_addr;
if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) {
free_vm_area(area);
return NULL;
}
return (void __iomem *)(vaddr + offset);
}
#ifndef ioremap_prot
void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
unsigned long prot)
{
return generic_ioremap_prot(phys_addr, size, __pgprot(prot));
}
EXPORT_SYMBOL(ioremap_prot);
#endif
void generic_iounmap(volatile void __iomem *addr)
{
void *vaddr = (void *)((unsigned long)addr & PAGE_MASK);
if (!iounmap_allowed(vaddr))
return;
if (is_vmalloc_addr(vaddr))
vunmap(vaddr);
}
#ifndef iounmap
void iounmap(volatile void __iomem *addr)
{
generic_iounmap(addr);
}
EXPORT_SYMBOL(iounmap);
#endif