From 5efc35640359c808746ce28a44262020b523abeb Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Mon, 12 Mar 2018 17:21:14 +0000 Subject: postcopy: helper for waking shared MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Provide a helper to send a 'wake' request on a userfaultfd for a shared process. The address in the clients address space is specified together with the RAMBlock it was resolved to. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Marc-André Lureau Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- migration/postcopy-ram.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'migration/postcopy-ram.c') diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index 8e08ff92f3..868f77b34d 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -525,6 +525,25 @@ static int ram_block_enable_notify(const char *block_name, void *host_addr, return 0; } +int postcopy_wake_shared(struct PostCopyFD *pcfd, + uint64_t client_addr, + RAMBlock *rb) +{ + size_t pagesize = qemu_ram_pagesize(rb); + struct uffdio_range range; + int ret; + trace_postcopy_wake_shared(client_addr, qemu_ram_get_idstr(rb)); + range.start = client_addr & ~(pagesize - 1); + range.len = pagesize; + ret = ioctl(pcfd->fd, UFFDIO_WAKE, &range); + if (ret) { + error_report("%s: Failed to wake: %zx in %s (%s)", + __func__, (size_t)client_addr, qemu_ram_get_idstr(rb), + strerror(errno)); + } + return ret; +} + /* * Callback from shared fault handlers to ask for a page, * the page must be specified by a RAMBlock and an offset in that rb @@ -961,6 +980,13 @@ void *postcopy_get_tmp_page(MigrationIncomingState *mis) return NULL; } +int postcopy_wake_shared(struct PostCopyFD *pcfd, + uint64_t client_addr, + RAMBlock *rb) +{ + assert(0); + return -1; +} #endif /* ------------------------------------------------------------------------- */ -- cgit v1.2.1