diff options
| author | Jérôme Glisse <jglisse@redhat.com> | 2018-04-10 16:28:34 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-11 10:28:30 -0700 |
| commit | 86586a41b8fe655e28be418a40e9bb2bb478cdd5 (patch) | |
| tree | d8ea7dec933ff425240e74a8521bbf6bbbd39450 /include/linux/hmm.h | |
| parent | 08232a4544cc6befaabfbec2087bedaf21b0da34 (diff) | |
mm/hmm: remove HMM_PFN_READ flag and ignore peculiar architecture
Only peculiar architecture allow write without read thus assume that any
valid pfn do allow for read. Note we do not care for write only because
it does make sense with thing like atomic compare and exchange or any
other operations that allow you to get the memory value through them.
Link: http://lkml.kernel.org/r/20180323005527.758-8-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/hmm.h')
| -rw-r--r-- | include/linux/hmm.h | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/include/linux/hmm.h b/include/linux/hmm.h index d0d6760cdada..dd907f614dfe 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -83,8 +83,7 @@ struct hmm; * hmm_pfn_t - HMM uses its own pfn type to keep several flags per page * * Flags: - * HMM_PFN_VALID: pfn is valid - * HMM_PFN_READ: CPU page table has read permission set + * HMM_PFN_VALID: pfn is valid. It has, at least, read permission. * HMM_PFN_WRITE: CPU page table has write permission set * HMM_PFN_ERROR: corresponding CPU page table entry points to poisoned memory * HMM_PFN_EMPTY: corresponding CPU page table entry is pte_none() @@ -97,13 +96,12 @@ struct hmm; typedef unsigned long hmm_pfn_t; #define HMM_PFN_VALID (1 << 0) -#define HMM_PFN_READ (1 << 1) -#define HMM_PFN_WRITE (1 << 2) -#define HMM_PFN_ERROR (1 << 3) -#define HMM_PFN_EMPTY (1 << 4) -#define HMM_PFN_SPECIAL (1 << 5) -#define HMM_PFN_DEVICE_UNADDRESSABLE (1 << 6) -#define HMM_PFN_SHIFT 7 +#define HMM_PFN_WRITE (1 << 1) +#define HMM_PFN_ERROR (1 << 2) +#define HMM_PFN_EMPTY (1 << 3) +#define HMM_PFN_SPECIAL (1 << 4) +#define HMM_PFN_DEVICE_UNADDRESSABLE (1 << 5) +#define HMM_PFN_SHIFT 6 /* * hmm_pfn_t_to_page() - return struct page pointed to by a valid hmm_pfn_t |