Hi Ian and Peter,
On 3/21/22 07:10, Peter Xu wrote:
On Fri, Mar 18, 2022 at 07:13:43PM +0000, Ian Abbott wrote:
Support for the `UFFDIO_WRITEPROTECT` operation is not indicated in the
`ioctls` member of `struct uffdio_api`. It is indicated in the `ioctls`
member of `struct uffdio_register` along with indications of support for
the `UFFDIO_COPY`, `UFFDIO_WAKE` and `UFFDIO_ZEROPAGE` operations (and
also the `UFFDIO_CONTINUE` operation supported since Linux 5.13 but
that is not documented by this man page yet.)
I thought it should have landed but indeed it's not. Copying Axel.
Fixes: f559fa36a678 ("ioctl_userfaultfd.2: Add write-protect mode docs")
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
Patch applied.
The patch looks correct to me, thanks for fixing it.
Acked-by: Peter Xu <peterx@xxxxxxxxxx>
And tag appended.
Thank you both!
Alex
---
man2/ioctl_userfaultfd.2 | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 deletions(-)
diff --git a/man2/ioctl_userfaultfd.2 b/man2/ioctl_userfaultfd.2
index 504f61d4b..e930af520 100644
--- a/man2/ioctl_userfaultfd.2
+++ b/man2/ioctl_userfaultfd.2
@@ -235,11 +235,6 @@ operation is supported.
The
.B UFFDIO_UNREGISTER
operation is supported.
-.TP
-.B 1 << _UFFDIO_WRITEPROTECT
-The
-.B UFFDIO_WRITEPROTECT
-operation is supported.
.PP
This
.BR ioctl (2)
@@ -333,8 +328,26 @@ If the operation is successful, the kernel modifies the
bit-mask field to indicate which
.BR ioctl (2)
operations are available for the specified range.
-This returned bit mask is as for
-.BR UFFDIO_API .
+This returned bit mask can contain the following bits:
+.TP
+.B 1 << _UFFDIO_COPY
+The
+.B UFFDIO_COPY
+operation is supported.
+.TP
+.B 1 << _UFFDIO_WAKE
+The
+.B UFFDIO_WAKE
+operation is supported.
+.TP
+.B 1 << _UFFDIO_WRITEPROTECT
+The
+.B UFFDIO_WRITEPROTECT
+.TP
+.B 1 << _UFFDIO_ZEROPAGE
+The
+.B UFFDIO_ZEROPAGE
+operation is supported.
.PP
This
.BR ioctl (2)
--
--
Alejandro Colomar
Linux man-pages comaintainer; http://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/
