LDP
/
man-pages
mirror of https://github.com/mkerrisk/man-pages
0
1
Fork 0
Code Releases Activity

ioctl_userfaultfd.2: Improve UFFDIO_REGISTER description 

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
Michael Kerrisk 2017-01-04 21:31:57 +13:00
parent 1b945386ca
commit 264a0a30ce
1 changed files with 34 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
man2/ioctl_userfaultfd.2
View File

@ -204,18 +204,44 @@ Track page faults on missing pages.
.B UFFDIO_REGISTER_MODE_WP
Track page faults on write-protected pages.
.PP
.\" FIXME Actually, the following sentence appears not to be true;
.\" UFFDIO_REGISTER_MODE_WP seems also to be supported.
.\" Can someone confirm?
Currently, the only supported mode is
.BR UFFDIO_REGISTER_MODE_MISSING .
.PP
.\" FIXME In the following, what does "answers" mean, and what are the bits?
.\" (we need a list of the bits here).
The kernel answers which ioctl commands are available for the requested
range in the
If the operation is successful, the kernel modifies the
.I ioctls
field.
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
.BR ioctl (2)
operation returns 0 on success.
On error, \-1 is returned and
.I errno
is set to indicate the cause of the error.
Possible errors include:
.\" FIXME Is the following error list correct?
.\"
.TP
.B EBUSY
A mapping in the specified range is registered with another
userfaultfd object.
.TP
.B EINVAL
An invalid or unsupported bit was specified in the
.I mode
field; or the
.I mode
field was zero.
.TP
.B EINVAL
There is no mapping in the specified address range.
.TP
.B EINVAL
There as an incompatible mapping in the specified address range.
.\" FIXME What does "incompatible" mean?
.\"
.SS UFFDIO_UNREGISTER
(Since Linux 4.3.)