summaryrefslogtreecommitdiffstats
path: root/fs/aio.c
diff options
context:
space:
mode:
authorMike Rapoport <rppt@linux.vnet.ibm.com>2017-02-24 14:58:22 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-24 17:46:55 -0800
commit897ab3e0c49e24b62e2d54d165c7afec6bbca65b (patch)
tree5fa7e09864d6c959cef33849f6cb10ed04e459e4 /fs/aio.c
parent846b1a0f1db065a8479159dd8fecddb1ebf30547 (diff)
downloadlinux-897ab3e0c49e24b62e2d54d165c7afec6bbca65b.tar.bz2
userfaultfd: non-cooperative: add event for memory unmaps
When a non-cooperative userfaultfd monitor copies pages in the background, it may encounter regions that were already unmapped. Addition of UFFD_EVENT_UNMAP allows the uffd monitor to track precisely changes in the virtual memory layout. Since there might be different uffd contexts for the affected VMAs, we first should create a temporary representation for the unmap event for each uffd context and then notify them one by one to the appropriate userfault file descriptors. The event notification occurs after the mmap_sem has been released. [arnd@arndb.de: fix nommu build] Link: http://lkml.kernel.org/r/20170203165141.3665284-1-arnd@arndb.de [mhocko@suse.com: fix nommu build] Link: http://lkml.kernel.org/r/20170202091503.GA22823@dhcp22.suse.cz Link: http://lkml.kernel.org/r/1485542673-24387-3-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pavel Emelyanov <xemul@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/aio.c')
-rw-r--r--fs/aio.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/aio.c b/fs/aio.c
index 873b4ca82ccb..7e2ab9c8e39c 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -512,7 +512,7 @@ static int aio_setup_ring(struct kioctx *ctx)
ctx->mmap_base = do_mmap_pgoff(ctx->aio_ring_file, 0, ctx->mmap_size,
PROT_READ | PROT_WRITE,
- MAP_SHARED, 0, &unused);
+ MAP_SHARED, 0, &unused, NULL);
up_write(&mm->mmap_sem);
if (IS_ERR((void *)ctx->mmap_base)) {
ctx->mmap_size = 0;