renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-17 17:53:56 +08:00
Code

Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Browse Source 
Pull memremap fix from Dan Williams:
 "The new memremap() api introduced in the 4.3 cycle to unify/replace
  ioremap_cache() and ioremap_wt() is mishandling the highmem case.
  This patch has received a build success notification from a
  0day-kbuild-robot run and has received an ack from Ard"

From the commit message:
 "The impact of this bug is low for now since the pmem driver is the
  only user of memremap(), but this is important to fix before more
  conversions to memremap arrive in 4.4"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  memremap: fix highmem support
This commit is contained in:
Linus Torvalds 2015-11-01 14:13:54 -08:00
commit 95fc00a4e1
1 changed files with 12 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
kernel/memremap.c
View File

@ -24,6 +24,16 @@ __weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
}
#endif
static void *try_ram_remap(resource_size_t offset, size_t size)
{
struct page *page = pfn_to_page(offset >> PAGE_SHIFT);
/* In the simple case just return the existing linear address */
if (!PageHighMem(page))
return __va(offset);
return NULL; /* fallback to ioremap_cache */
}
/**
* memremap() - remap an iomem_resource as cacheable memory
* @offset: iomem resource start address
@ -66,8 +76,8 @@ void *memremap(resource_size_t offset, size_t size, unsigned long flags)
* the requested range is potentially in "System RAM"
*/
if (is_ram == REGION_INTERSECTS)
addr = __va(offset);
else
addr = try_ram_remap(offset, size);
if (!addr)
addr = ioremap_cache(offset, size);
}