Re: [PATCH v4 5/6] arm64: mm: Convert to GENERIC_IOREMAP

From: Kefeng Wang
Date: Mon Jun 06 2022 - 09:28:33 EST



On 2022/6/6 15:54, Christoph Hellwig wrote:
+#define ioremap_wc(addr, size) ioremap_prot((addr), (size), PROT_NORMAL_NC)
+#define ioremap_np(addr, size) ioremap_prot((addr), (size), PROT_DEVICE_nGnRnE)
Please avoid the overly long lines here. Independt of that having
a non-trivial body on a separate line tends to generlly be a lot more
readable anyway.

Hi Christoph,

As commit bdc48fa11e46  ("checkpatch/coding-style: deprecate 80-column warning") increased

the limit to 100 columns,so I don't get warning when using checkpatch, and it is not a hard limit,

but if this is a mandatory requirement, I will resend them with break lines.

+#define ioremap_cache(addr, size) ({ \
+ pfn_is_map_memory(__phys_to_pfn(addr)) ? \
+ (void __iomem *)__phys_to_virt(addr) : ioremap_prot(addr, size, PROT_NORMAL); \
+})
And this really should be an inline function.

We still need a define, see kernel/iomem.c,

#ifndef ioremap_cache
__weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
{
        return ioremap(offset, size);
}
#endif


+int iounmap_allowed(void __iomem *addr)
{
/*
* We could get an address outside vmalloc range in case
* of ioremap_cache() reusing a RAM mapping.
*/
+ return is_vmalloc_addr(addr) ? 0 : -EINVAL;
As the generic ioremap only returns vmalloc addresses, this check
really should go into common code.

Good point, will move into generic ioremap, thanks.

.