From 51a5d6e5b20077c1657593a60b300f611ab7049f Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Mon, 12 Mar 2018 17:21:09 +0000 Subject: libvhost-user+postcopy: Register new regions with the ufd MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When new regions are sent to the client using SET_MEM_TABLE, register them with the userfaultfd. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Marc-AndrĂ© Lureau Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- contrib/libvhost-user/libvhost-user.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index b2de8ed0a8..7c8cd5878e 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -494,6 +494,40 @@ vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg) close(vmsg->fds[i]); } + /* TODO: Get address back to QEMU */ + for (i = 0; i < dev->nregions; i++) { + VuDevRegion *dev_region = &dev->regions[i]; +#ifdef UFFDIO_REGISTER + /* We should already have an open ufd. Mark each memory + * range as ufd. + * Note: Do we need any madvises? Well it's not been accessed + * yet, still probably need no THP to be safe, discard to be safe? + */ + struct uffdio_register reg_struct; + reg_struct.range.start = (uintptr_t)dev_region->mmap_addr; + reg_struct.range.len = dev_region->size + dev_region->mmap_offset; + reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING; + + if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER, ®_struct)) { + vu_panic(dev, "%s: Failed to userfault region %d " + "@%p + size:%zx offset: %zx: (ufd=%d)%s\n", + __func__, i, + dev_region->mmap_addr, + dev_region->size, dev_region->mmap_offset, + dev->postcopy_ufd, strerror(errno)); + return false; + } + if (!(reg_struct.ioctls & ((__u64)1 << _UFFDIO_COPY))) { + vu_panic(dev, "%s Region (%d) doesn't support COPY", + __func__, i); + return false; + } + DPRINT("%s: region %d: Registered userfault for %llx + %llx\n", + __func__, i, reg_struct.range.start, reg_struct.range.len); + /* TODO: Stash 'zero' support flags somewhere */ +#endif + } + return false; } -- cgit v1.2.1