diff options
author | Rodrigo Vivi <[email protected]> | 2018-07-23 09:13:12 -0700 |
---|---|---|
committer | Rodrigo Vivi <[email protected]> | 2018-07-23 09:13:12 -0700 |
commit | c74a7469f97c0f40b46e82ee979f9fb1bb6e847c (patch) | |
tree | f2690a1a916b73ef94657fbf0e0141ae57701825 /mm/userfaultfd.c | |
parent | 6f15a7de86c8cf2dc09fc9e6d07047efa40ef809 (diff) | |
parent | 500775074f88d9cf5416bed2ca19592812d62c41 (diff) |
Merge drm/drm-next into drm-intel-next-queued
We need a backmerge to get DP_DPCD_REV_14 before we push other
i915 changes to dinq that could break compilation.
Signed-off-by: Rodrigo Vivi <[email protected]>
Diffstat (limited to 'mm/userfaultfd.c')
-rw-r--r-- | mm/userfaultfd.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 39791b81ede7..5029f241908f 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -404,7 +404,8 @@ static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long src_start, unsigned long len, - bool zeropage) + bool zeropage, + bool *mmap_changing) { struct vm_area_struct *dst_vma; ssize_t err; @@ -431,6 +432,15 @@ retry: down_read(&dst_mm->mmap_sem); /* + * If memory mappings are changing because of non-cooperative + * operation (e.g. mremap) running in parallel, bail out and + * request the user to retry later + */ + err = -EAGAIN; + if (mmap_changing && READ_ONCE(*mmap_changing)) + goto out_unlock; + + /* * Make sure the vma is not shared, that the dst range is * both valid and fully within a single existing vma. */ @@ -563,13 +573,15 @@ out: } ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start, - unsigned long src_start, unsigned long len) + unsigned long src_start, unsigned long len, + bool *mmap_changing) { - return __mcopy_atomic(dst_mm, dst_start, src_start, len, false); + return __mcopy_atomic(dst_mm, dst_start, src_start, len, false, + mmap_changing); } ssize_t mfill_zeropage(struct mm_struct *dst_mm, unsigned long start, - unsigned long len) + unsigned long len, bool *mmap_changing) { - return __mcopy_atomic(dst_mm, start, 0, len, true); + return __mcopy_atomic(dst_mm, start, 0, len, true, mmap_changing); } |