2 * An implementation of host to guest copy functionality for Linux.
4 * Copyright (C) 2014, Microsoft, Inc.
6 * Author : K. Y. Srinivasan <kys@microsoft.com>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15 * NON INFRINGEMENT. See the GNU General Public License for more
20 #include <sys/types.h>
25 #include <linux/hyperv.h>
32 static char target_fname[W_MAX_PATH];
33 static unsigned long long filesize;
35 static int hv_start_fcopy(struct hv_start_fcopy *smsg)
37 int error = HV_E_FAIL;
41 p = (char *)smsg->path_name;
42 snprintf(target_fname, sizeof(target_fname), "%s/%s",
43 (char *)smsg->path_name, (char *)smsg->file_name);
45 syslog(LOG_INFO, "Target file name: %s", target_fname);
47 * Check to see if the path is already in place; if not,
50 while ((q = strchr(p, '/')) != NULL) {
56 if (access((char *)smsg->path_name, F_OK)) {
57 if (smsg->copy_flags & CREATE_PATH) {
58 if (mkdir((char *)smsg->path_name, 0755)) {
59 syslog(LOG_ERR, "Failed to create %s",
60 (char *)smsg->path_name);
64 syslog(LOG_ERR, "Invalid path: %s",
65 (char *)smsg->path_name);
73 if (!access(target_fname, F_OK)) {
74 syslog(LOG_INFO, "File: %s exists", target_fname);
75 if (!(smsg->copy_flags & OVER_WRITE)) {
76 error = HV_ERROR_ALREADY_EXISTS;
81 target_fd = open(target_fname,
82 O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0744);
83 if (target_fd == -1) {
84 syslog(LOG_INFO, "Open Failed: %s", strerror(errno));
93 static int hv_copy_data(struct hv_do_fcopy *cpmsg)
95 ssize_t bytes_written;
98 bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size,
101 filesize += cpmsg->size;
102 if (bytes_written != cpmsg->size) {
105 ret = HV_ERROR_DISK_FULL;
111 syslog(LOG_ERR, "pwrite failed to write %llu bytes: %ld (%s)",
112 filesize, (long)bytes_written, strerror(errno));
118 static int hv_copy_finished(void)
123 static int hv_copy_cancel(void)
126 unlink(target_fname);
131 void print_usage(char *argv[])
133 fprintf(stderr, "Usage: %s [options]\n"
135 " -n, --no-daemon stay in foreground, don't daemonize\n"
136 " -h, --help print this help\n", argv[0]);
139 int main(int argc, char *argv[])
143 int daemonize = 1, long_index = 0, opt;
144 int version = FCOPY_CURRENT_VERSION;
145 char *buffer[4096 * 2];
146 struct hv_fcopy_hdr *in_msg;
147 int in_handshake = 1;
150 static struct option long_options[] = {
151 {"help", no_argument, 0, 'h' },
152 {"no-daemon", no_argument, 0, 'n' },
156 while ((opt = getopt_long(argc, argv, "hn", long_options,
157 &long_index)) != -1) {
169 if (daemonize && daemon(1, 0)) {
170 syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno));
174 openlog("HV_FCOPY", 0, LOG_USER);
175 syslog(LOG_INFO, "starting; pid is:%d", getpid());
177 fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR);
180 syslog(LOG_ERR, "open /dev/vmbus/hv_fcopy failed; error: %d %s",
181 errno, strerror(errno));
186 * Register with the kernel.
188 if ((write(fcopy_fd, &version, sizeof(int))) != sizeof(int)) {
189 syslog(LOG_ERR, "Registration failed: %s", strerror(errno));
195 * In this loop we process fcopy messages after the
196 * handshake is complete.
198 len = pread(fcopy_fd, buffer, (4096 * 2), 0);
200 syslog(LOG_ERR, "pread failed: %s", strerror(errno));
205 if (len != sizeof(kernel_modver)) {
206 syslog(LOG_ERR, "invalid version negotiation");
209 kernel_modver = *(__u32 *)buffer;
211 syslog(LOG_INFO, "kernel module version: %d",
216 in_msg = (struct hv_fcopy_hdr *)buffer;
218 switch (in_msg->operation) {
219 case START_FILE_COPY:
220 error = hv_start_fcopy((struct hv_start_fcopy *)in_msg);
223 error = hv_copy_data((struct hv_do_fcopy *)in_msg);
226 error = hv_copy_finished();
229 error = hv_copy_cancel();
233 syslog(LOG_ERR, "Unknown operation: %d",
238 if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) {
239 syslog(LOG_ERR, "pwrite failed: %s", strerror(errno));