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Diffstat (limited to 'tools/hv/hv_fcopy_daemon.c')
-rw-r--r--tools/hv/hv_fcopy_daemon.c37
1 files changed, 32 insertions, 5 deletions
diff --git a/tools/hv/hv_fcopy_daemon.c b/tools/hv/hv_fcopy_daemon.c
index aea2d91ab364..16d629b22c25 100644
--- a/tools/hv/hv_fcopy_daemon.c
+++ b/tools/hv/hv_fcopy_daemon.c
@@ -80,6 +80,8 @@ static int hv_start_fcopy(struct hv_start_fcopy *smsg)
error = 0;
done:
+ if (error)
+ target_fname[0] = '\0';
return error;
}
@@ -108,15 +110,29 @@ static int hv_copy_data(struct hv_do_fcopy *cpmsg)
return ret;
}
+/*
+ * Reset target_fname to "" in the two below functions for hibernation: if
+ * the fcopy operation is aborted by hibernation, the daemon should remove the
+ * partially-copied file; to achieve this, the hv_utils driver always fakes a
+ * CANCEL_FCOPY message upon suspend, and later when the VM resumes back,
+ * the daemon calls hv_copy_cancel() to remove the file; if a file is copied
+ * successfully before suspend, hv_copy_finished() must reset target_fname to
+ * avoid that the file can be incorrectly removed upon resume, since the faked
+ * CANCEL_FCOPY message is spurious in this case.
+ */
static int hv_copy_finished(void)
{
close(target_fd);
+ target_fname[0] = '\0';
return 0;
}
static int hv_copy_cancel(void)
{
close(target_fd);
- unlink(target_fname);
+ if (strlen(target_fname) > 0) {
+ unlink(target_fname);
+ target_fname[0] = '\0';
+ }
return 0;
}
@@ -131,7 +147,7 @@ void print_usage(char *argv[])
int main(int argc, char *argv[])
{
- int fcopy_fd;
+ int fcopy_fd = -1;
int error;
int daemonize = 1, long_index = 0, opt;
int version = FCOPY_CURRENT_VERSION;
@@ -141,7 +157,7 @@ int main(int argc, char *argv[])
struct hv_do_fcopy copy;
__u32 kernel_modver;
} buffer = { };
- int in_handshake = 1;
+ int in_handshake;
static struct option long_options[] = {
{"help", no_argument, 0, 'h' },
@@ -170,6 +186,12 @@ int main(int argc, char *argv[])
openlog("HV_FCOPY", 0, LOG_USER);
syslog(LOG_INFO, "starting; pid is:%d", getpid());
+reopen_fcopy_fd:
+ if (fcopy_fd != -1)
+ close(fcopy_fd);
+ /* Remove any possible partially-copied file on error */
+ hv_copy_cancel();
+ in_handshake = 1;
fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR);
if (fcopy_fd < 0) {
@@ -196,7 +218,7 @@ int main(int argc, char *argv[])
len = pread(fcopy_fd, &buffer, sizeof(buffer), 0);
if (len < 0) {
syslog(LOG_ERR, "pread failed: %s", strerror(errno));
- exit(EXIT_FAILURE);
+ goto reopen_fcopy_fd;
}
if (in_handshake) {
@@ -231,9 +253,14 @@ int main(int argc, char *argv[])
}
+ /*
+ * pwrite() may return an error due to the faked CANCEL_FCOPY
+ * message upon hibernation. Ignore the error by resetting the
+ * dev file, i.e. closing and re-opening it.
+ */
if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) {
syslog(LOG_ERR, "pwrite failed: %s", strerror(errno));
- exit(EXIT_FAILURE);
+ goto reopen_fcopy_fd;
}
}
}