From 80b0ca98f91ddbc09828aff5a00af1c73837713e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 13 Aug 2019 11:24:04 +0200 Subject: lib: provide a simple generic ioremap implementation A lot of architectures reuse the same simple ioremap implementation, so start lifting the most simple variant to lib/ioremap.c. It provides ioremap_prot and iounmap, plus a default ioremap that uses prot_noncached, although that can be overridden by asm/io.h. Signed-off-by: Christoph Hellwig Reviewed-by: Arnd Bergmann Reviewed-by: Palmer Dabbelt --- lib/ioremap.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) (limited to 'lib/ioremap.c') diff --git a/lib/ioremap.c b/lib/ioremap.c index 0a2ffadc6d71..3f0e18543de8 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -231,3 +231,42 @@ int ioremap_page_range(unsigned long addr, return err; } + +#ifdef CONFIG_GENERIC_IOREMAP +void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot) +{ + unsigned long offset, vaddr; + phys_addr_t last_addr; + struct vm_struct *area; + + /* Disallow wrap-around or zero size */ + last_addr = addr + size - 1; + if (!size || last_addr < addr) + return NULL; + + /* Page-align mappings */ + offset = addr & (~PAGE_MASK); + addr -= offset; + size = PAGE_ALIGN(size + offset); + + area = get_vm_area_caller(size, VM_IOREMAP, + __builtin_return_address(0)); + if (!area) + return NULL; + vaddr = (unsigned long)area->addr; + + if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) { + free_vm_area(area); + return NULL; + } + + return (void __iomem *)(vaddr + offset); +} +EXPORT_SYMBOL(ioremap_prot); + +void iounmap(volatile void __iomem *addr) +{ + vunmap((void *)((unsigned long)addr & PAGE_MASK)); +} +EXPORT_SYMBOL(iounmap); +#endif /* CONFIG_GENERIC_IOREMAP */ -- cgit v1.2.3