Re: [PATCH v3 03/11] mm/ioremap: change the return value of io[re|un]map_allowed and rename

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 2022/10/10 8:25, Baoquan He wrote:
On 10/09/22 at 07:13pm, Kefeng Wang wrote:
On 2022/10/9 18:31, Baoquan He wrote:
Currently, hooks ioremap_allowed() and iounmap_allowed() are used to
check if it's qualified to do ioremap, and now this is done on ARM64.
However, in oder to convert more architectures to take GENERIC_IOREMAP
method, several more things need be done in those two hooks:
   1) The io address mapping need be handled specifically on architectures,
      e.g arc, ia64, s390;
   2) The original physical address passed into ioremap_prot() need be
      fixed up, e.g arc;
   3) The 'prot' passed into ioremap_prot() need be adjusted, e.g on arc
      and xtensa.

To handle these three issues,

   1) Rename ioremap_allowed() and iounmap_allowed() to arch_ioremap()
      and arch_iounmap() since the old name can't reflect their
      functionality after change;
   2) Change the return value of arch_ioremap() so that arch can add
      specifical io address mapping handling inside and return the maped
      address. Now their returned value means:
      ===
      arch_ioremap() return a bool,
pointer?
Right, I forgot fixing it again. Thanks.

        - IS_ERR means return an error
        - 0 means continue to remap
        - a non-zero, non-IS_ERR pointer is returned directly
      arch_iounmap() return a bool,
        - true means continue to vunmap
        - false means skip vunmap and return directly
...
   /*
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index a68f8fbf423b..2ae16906f3be 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -1049,25 +1049,26 @@ static inline void iounmap(volatile void __iomem *addr)
   /*
    * Arch code can implement the following two hooks when using GENERIC_IOREMAP
- * ioremap_allowed() return a bool,
- *   - true means continue to remap
- *   - false means skip remap and return directly
- * iounmap_allowed() return a bool,
+ * arch_ioremap() return a bool,
ditto...
Will change.

   	area = get_vm_area_caller(size, VM_IOREMAP,
   			__builtin_return_address(0));
   	if (!area)
@@ -52,7 +57,7 @@ void iounmap(volatile void __iomem *addr)
   {
   	void *vaddr = (void *)((unsigned long)addr & PAGE_MASK);
-	if (!iounmap_allowed(vaddr))
+	if (!arch_iounmap((void __iomem *)addr))
vaddr?
No, it's intentional. Alexander suggested this, both of you discussed
this in v1, see below thread.
ok, please ignore it.
https://lore.kernel.org/all/Yu4mYxpV0GWRTjQp@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#u

   		return;
   	if (is_vmalloc_addr(vaddr))

.



[Index of Archives]     [Linux Kernel]     [Kernel Newbies]     [x86 Platform Driver]     [Netdev]     [Linux Wireless]     [Netfilter]     [Bugtraq]     [Linux Filesystems]     [Yosemite Discussion]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]

  Powered by Linux