Commit graph

4 commits

Author SHA1 Message Date
Peter Maydell
493bc2dbc1 misc: Clean up includes
This commit was created with scripts/clean-includes:
 ./scripts/clean-includes --git misc net/af-xdp.c plugins/*.c audio/pwaudio.c util/userfaultfd.c

All .c should include qemu/osdep.h first.  The script performs three
related cleanups:

* Ensure .c files include qemu/osdep.h first.
* Including it in a .h is redundant, since the .c  already includes
  it.  Drop such inclusions.
* Likewise, including headers qemu/osdep.h includes is redundant.
  Drop these, too.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2024-01-30 21:20:20 +03:00
Peter Xu
c40c046341 util/userfaultfd: Support /dev/userfaultfd
Teach QEMU to use /dev/userfaultfd when it existed and fallback to the
system call if either it's not there or doesn't have enough permission.

Firstly, as long as the app has permission to access /dev/userfaultfd, it
always have the ability to trap kernel faults which QEMU mostly wants.
Meanwhile, in some context (e.g. containers) the userfaultfd syscall can be
forbidden, so it can be the major way to use postcopy in a restricted
environment with strict seccomp setup.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-11 16:51:09 +01:00
Peter Xu
d5890ea072 util/userfaultfd: Add uffd_open()
Add a helper to create the uffd handle.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:56 +01:00
Andrey Gruzdev
0e9b5cd6b2 migration: introduce UFFD-WP low-level interface helpers
Glue code to the userfaultfd kernel implementation.
Querying feature support, createing file descriptor, feature control,
memory region registration, IOCTLs on registered registered regions.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210129101407.103458-3-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Fixed up range.start casting for 32bit
2021-02-08 11:19:51 +00:00