From f047435a1087f438c645d729f68f6578e8cb861d Mon Sep 17 00:00:00 2001

From: "Richard W.M. Jones" <rjones@redhat.com>

Date: Thu, 30 Mar 2017 13:13:03 +0100

Subject: [PATCH] p2v: Run fewer 'scp' commands.

Each scp command takes a considerable amount of time -- several

seconds -- because it must set up, authenticate and tear down a new

connection.  Avoid this by combining several copies into a single

command.

We still have to use two scp commands because we want to check that

some files are copied and ignore failures in a second set of

informational files.

(cherry picked from commit d178deeeb814471b9d70431626b6cd515a21d0c1)

---

 p2v/conversion.c | 31 +++++++++++--------------------

 p2v/p2v.h        |  2 +-

 p2v/ssh.c        | 25 +++++++++++++++++++++----

 3 files changed, 33 insertions(+), 25 deletions(-)

diff --git a/p2v/conversion.c b/p2v/conversion.c

index beda2b8..0da9a62 100644

--- a/p2v/conversion.c

+++ b/p2v/conversion.c

@@ -366,28 +366,19 @@ start_conversion (struct config *config,

   }

   /* Copy the static files to the remote dir. */

-  if (scp_file (config, name_file, remote_dir) == -1) {

-    set_conversion_error ("scp: %s to %s: %s",

-                          name_file, remote_dir, get_ssh_error ());

+

+  /* These three files must not fail, so check for errors here. */

+  if (scp_file (config, remote_dir,

+                name_file, libvirt_xml_file, wrapper_script, NULL) == -1) {

+    set_conversion_error ("scp: %s: %s",

+                          remote_dir, get_ssh_error ());

     goto out;

   }

-  if (scp_file (config, libvirt_xml_file, remote_dir) == -1) {

-    set_conversion_error ("scp: %s to %s: %s",

-                          libvirt_xml_file, remote_dir, get_ssh_error ());

-    goto out;

-  }

-  if (scp_file (config, wrapper_script, remote_dir) == -1) {

-    set_conversion_error ("scp: %s to %s: %s",

-                          wrapper_script, remote_dir, get_ssh_error ());

-    goto out;

-  }

-  /* It's not essential that these files are copied. */

-  ignore_value (scp_file (config, dmesg_file, remote_dir));

-  ignore_value (scp_file (config, lscpu_file, remote_dir));

-  ignore_value (scp_file (config, lspci_file, remote_dir));

-  ignore_value (scp_file (config, lsscsi_file, remote_dir));

-  ignore_value (scp_file (config, lsusb_file, remote_dir));

-  ignore_value (scp_file (config, p2v_version_file, remote_dir));

+

+  /* It's not essential that these files are copied, so ignore errors. */

+  ignore_value (scp_file (config, remote_dir,

+                          dmesg_file, lscpu_file, lspci_file, lsscsi_file,

+                          lsusb_file, p2v_version_file, NULL));

   /* Do the conversion.  This runs until virt-v2v exits. */

   if (notify_ui)

diff --git a/p2v/p2v.h b/p2v/p2v.h

index 5223aa2..b26648a 100644

--- a/p2v/p2v.h

+++ b/p2v/p2v.h

@@ -128,7 +128,7 @@ extern int test_connection (struct config *);

 extern mexp_h *open_data_connection (struct config *, const char *local_ipaddr, int local_port, int *remote_port);

 extern mexp_h *start_remote_connection (struct config *, const char *remote_dir);

 extern const char *get_ssh_error (void);

-extern int scp_file (struct config *config, const char *localfile, const char *remotefile);

+extern int scp_file (struct config *config, const char *target, const char *local, ...) __attribute__((sentinel));

 /* nbd.c */

 extern void set_nbd_option (const char *opt);

diff --git a/p2v/ssh.c b/p2v/ssh.c

index 8beaf74..bfeb806 100644

--- a/p2v/ssh.c

+++ b/p2v/ssh.c

@@ -572,14 +572,18 @@ start_ssh (unsigned spawn_flags, struct config *config,

 #endif

 /**

- * Upload a file to remote using L<scp(1)>.

+ * Upload file(s) to remote using L<scp(1)>.

+ *

+ * Note that the target (directory or file) comes before the list of

+ * local files, because the list of local files is a varargs list.

  *

  * This is a simplified version of L</start_ssh> above.

  */

 int

-scp_file (struct config *config, const char *localfile, const char *remotefile)

+scp_file (struct config *config, const char *target, const char *local, ...)

 {

   size_t i = 0;

+  va_list args;

   const size_t MAX_ARGS = 64;

   const char *argv[MAX_ARGS];

   char port_str[64];

@@ -618,12 +622,25 @@ scp_file (struct config *config, const char *localfile, const char *remotefile)

     ADD_ARG (argv, i, "-i");

     ADD_ARG (argv, i, config->identity_file);

   }

-  ADD_ARG (argv, i, localfile);

+

+  /* Source files or directories.

+   * Strictly speaking this could abort() if the list of files is

+   * too long, but that never happens in virt-p2v. XXX

+   */

+  va_start (args, local);

+  do ADD_ARG (argv, i, local);

+  while ((local = va_arg (args, const char *)) != NULL);

+  va_end (args);

+

+  /* The target file or directory.  We need to rewrite this as

+   * "username@server:target".

+   */

   if (asprintf (&remote, "%s@%s:%s",

                 config->username ? config->username : "root",

-                config->server, remotefile) == -1)

+                config->server, target) == -1)

     error (EXIT_FAILURE, errno, "asprintf");

   ADD_ARG (argv, i, remote);

+

   ADD_ARG (argv, i, NULL);

 #if DEBUG_STDERR

-- 

2.9.4