userfaultfd: non-cooperative: rename *EVENT_MADVDONTNEED to *EVENT_REMOVE

Patch series "userfaultfd: non-cooperative: add madvise() event for
MADV_REMOVE request".

These patches add notification of madvise(MADV_REMOVE) event to
non-cooperative userfaultfd monitor.

The first pacth renames EVENT_MADVDONTNEED to EVENT_REMOVE along with
relevant functions and structures.  Using _REMOVE instead of
_MADVDONTNEED describes the event semantics more clearly and I hope it's
not too late for such change in the ABI.

This patch (of 3):

The UFFD_EVENT_MADVDONTNEED purpose is to notify uffd monitor about
removal of certain range from address space tracked by userfaultfd.
Hence, UFFD_EVENT_REMOVE seems to better reflect the operation
semantics.  Respectively, 'madv_dn' field of uffd_msg is renamed to
'remove' and the madvise_userfault_dontneed callback is renamed to
userfaultfd_remove.

Link: http://lkml.kernel.org/r/1484814154-1557-2-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 8 deletions

diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
index 5a840a605a16..9eb77df568f7 100644
--- a/tools/testing/selftests/vm/userfaultfd.c
+++ b/tools/testing/selftests/vm/userfaultfd.c
@@ -398,12 +398,12 @@ static void *uffd_poll_thread(void *arg)
 			uffd = msg.arg.fork.ufd;
 			pollfd[0].fd = uffd;
 			break;
-		case UFFD_EVENT_MADVDONTNEED:
-			uffd_reg.range.start = msg.arg.madv_dn.start;
-			uffd_reg.range.len = msg.arg.madv_dn.end -
-				msg.arg.madv_dn.start;
+		case UFFD_EVENT_REMOVE:
+			uffd_reg.range.start = msg.arg.remove.start;
+			uffd_reg.range.len = msg.arg.remove.end -
+				msg.arg.remove.start;
 			if (ioctl(uffd, UFFDIO_UNREGISTER, &uffd_reg.range))
-				fprintf(stderr, "madv_dn failure\n"), exit(1);
+				fprintf(stderr, "remove failure\n"), exit(1);
 			break;
 		case UFFD_EVENT_REMAP:
 			area_dst = (char *)(unsigned long)msg.arg.remap.to;
@@ -570,7 +570,7 @@ static int userfaultfd_open(int features)
  * mremap, the entire monitored area is accessed in a single pass for
  * HUGETLB_TEST.
  * The release of the pages currently generates event only for
- * anonymous memory (UFFD_EVENT_MADVDONTNEED), hence it is not checked
+ * anonymous memory (UFFD_EVENT_REMOVE), hence it is not checked
  * for hugetlb and shmem.
  */
 static int faulting_process(void)
@@ -715,14 +715,14 @@ static int userfaultfd_events_test(void)
 	pid_t pid;
 	char c;
 
-	printf("testing events (fork, remap, madv_dn): ");
+	printf("testing events (fork, remap, remove): ");
 	fflush(stdout);
 
 	if (release_pages(area_dst))
 		return 1;
 
 	features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP |
-		UFFD_FEATURE_EVENT_MADVDONTNEED;
+		UFFD_FEATURE_EVENT_REMOVE;
 	if (userfaultfd_open(features) < 0)
 		return 1;
 	fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);