diff options
| author | Jérôme Glisse <jglisse@redhat.com> | 2017-09-08 16:11:35 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-09-08 18:26:46 -0700 |
| commit | 74eee180b935fcb9b83a56dd7648fb75caf38f0e (patch) | |
| tree | 6854a66ea69d108728487454c06dc257e4c17a14 /include | |
| parent | da4c3c735ea4dcc2a0b0ff0bd4803c336361b6f5 (diff) | |
mm/hmm/mirror: device page fault handler
This handles page fault on behalf of device driver, unlike
handle_mm_fault() it does not trigger migration back to system memory for
device memory.
Link: http://lkml.kernel.org/r/20170817000548.32038-6-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com>
Signed-off-by: Sherry Cheung <SCheung@nvidia.com>
Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/hmm.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 62899c9829c9..61a6535fe438 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -292,6 +292,33 @@ int hmm_vma_get_pfns(struct vm_area_struct *vma, unsigned long end, hmm_pfn_t *pfns); bool hmm_vma_range_done(struct vm_area_struct *vma, struct hmm_range *range); + + +/* + * Fault memory on behalf of device driver. Unlike handle_mm_fault(), this will + * not migrate any device memory back to system memory. The hmm_pfn_t array will + * be updated with the fault result and current snapshot of the CPU page table + * for the range. + * + * The mmap_sem must be taken in read mode before entering and it might be + * dropped by the function if the block argument is false. In that case, the + * function returns -EAGAIN. + * + * Return value does not reflect if the fault was successful for every single + * address or not. Therefore, the caller must to inspect the hmm_pfn_t array to + * determine fault status for each address. + * + * Trying to fault inside an invalid vma will result in -EINVAL. + * + * See the function description in mm/hmm.c for further documentation. + */ +int hmm_vma_fault(struct vm_area_struct *vma, + struct hmm_range *range, + unsigned long start, + unsigned long end, + hmm_pfn_t *pfns, + bool write, + bool block); #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ |