diff options
| author |   Andi Kleen <ak@linux.intel.com> | 2010-10-06 21:45:00 +0200 |
|---|---|---|
| committer | Andi Kleen <ak@linux.intel.com> | 2010-10-08 09:32:46 +0200 |
| commit | aa50d3a7aa8147b9e14dc9d5972a5d2359db4ef8 (patch) | |
| tree | 68fae5060333dcc24c17e9dd00a87bd760d883e9 /include/linux/mm.h | |
| parent | Fix build error with !CONFIG_MIGRATION (diff) | |
| download | linux-dev-aa50d3a7aa8147b9e14dc9d5972a5d2359db4ef8.tar.xz linux-dev-aa50d3a7aa8147b9e14dc9d5972a5d2359db4ef8.zip | |
Encode huge page size for VM_FAULT_HWPOISON errors
This fixes a problem introduced with the hugetlb hwpoison handling
The user space SIGBUS signalling wants to know the size of the hugepage
that caused a HWPOISON fault.
Unfortunately the architecture page fault handlers do not have easy
access to the struct page.
Pass the information out in the fault error code instead.
I added a separate VM_FAULT_HWPOISON_LARGE bit for this case and encode
the hpage index in some free upper bits of the fault code. The small
page hwpoison keeps stays with the VM_FAULT_HWPOISON name to minimize
changes.
Also add code to hugetlb.h to convert that index into a page shift.
Will be used in a further patch.
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: fengguang.wu@intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 74949fbef8c6..f7e9efc6720b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -718,12 +718,20 @@ static inline int page_mapped(struct page *page) #define VM_FAULT_SIGBUS 0x0002 #define VM_FAULT_MAJOR 0x0004 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */ -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned page */ +#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */ +#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index encoded in upper bits */ #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */ #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */ -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON) +#define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */ + +#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | \ + VM_FAULT_HWPOISON_LARGE) + +/* Encode hstate index for a hwpoisoned large page */ +#define VM_FAULT_SET_HINDEX(x) ((x) << 12) +#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf) /* * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. |