replay: update docs for record/replay with block devices

This patch updates the description of the command lines for using
record/replay with attached block devices.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/docs/replay.txt b/docs/replay.txt
index ee6aee9..ce97c3f 100644 (file)
--- a/docs/replay.txt
+++ b/docs/replay.txt
@@ -27,7 +27,7 @@ Usage of the record/replay:
  * First, record the execution with the following command line:
     qemu-system-i386 \
      -icount shift=7,rr=record,rrfile=replay.bin \
-     -drive file=disk.qcow2,if=none,id=img-direct \
+     -drive file=disk.qcow2,if=none,snapshot,id=img-direct \
      -drive driver=blkreplay,if=none,image=img-direct,id=img-blkreplay \
      -device ide-hd,drive=img-blkreplay \
      -netdev user,id=net1 -device rtl8139,netdev=net1 \
@@ -35,7 +35,7 @@ Usage of the record/replay:
  * After recording, you can replay it by using another command line:
     qemu-system-i386 \
      -icount shift=7,rr=replay,rrfile=replay.bin \
-     -drive file=disk.qcow2,if=none,id=img-direct \
+     -drive file=disk.qcow2,if=none,snapshot,id=img-direct \
      -drive driver=blkreplay,if=none,image=img-direct,id=img-blkreplay \
      -device ide-hd,drive=img-blkreplay \
      -netdev user,id=net1 -device rtl8139,netdev=net1 \
@@ -223,7 +223,7 @@ Block devices record/replay module intercepts calls of
 bdrv coroutine functions at the top of block drivers stack.
 To record and replay block operations the drive must be configured
 as following:
- -drive file=disk.qcow2,if=none,id=img-direct
+ -drive file=disk.qcow2,if=none,snapshot,id=img-direct
  -drive driver=blkreplay,if=none,image=img-direct,id=img-blkreplay
  -device ide-hd,drive=img-blkreplay
 
@@ -252,6 +252,12 @@ This snapshot is created at start of recording and restored at start
 of replaying. It also can be loaded while replaying to roll back
 the execution.
 
+'snapshot' flag of the disk image must be removed to save the snapshots
+in the overlay (or original image) instead of using the temporary overlay.
+ -drive file=disk.ovl,if=none,id=img-direct
+ -drive driver=blkreplay,if=none,image=img-direct,id=img-blkreplay
+ -device ide-hd,drive=img-blkreplay
+
 Use QEMU monitor to create additional snapshots. 'savevm <name>' command
 created the snapshot and 'loadvm <name>' restores it. To prevent corruption
 of the original disk image, use overlay files linked to the original images.