@@ -3890,6 +3890,7 @@ M: Stefan Hajnoczi <stefanha@redhat.com>
L: qemu-block@nongnu.org
S: Supported
F: block/blkverify.c
+F: docs/devel/blkverify.rst
bochs
M: Stefan Hajnoczi <stefanha@redhat.com>
similarity index 77%
rename from docs/devel/blkverify.txt
rename to docs/devel/testing/blkverify.rst
@@ -1,8 +1,10 @@
-= Block driver correctness testing with blkverify =
+Block driver correctness testing with ``blkverify``
+===================================================
-== Introduction ==
+Introduction
+------------
-This document describes how to use the blkverify protocol to test that a block
+This document describes how to use the ``blkverify`` protocol to test that a block
driver is operating correctly.
It is difficult to test and debug block drivers against real guests. Often
@@ -11,12 +13,13 @@ of the executable. Other times obscure errors are raised by a program inside
the guest. These issues are extremely hard to trace back to bugs in the block
driver.
-Blkverify solves this problem by catching data corruption inside QEMU the first
+``blkverify`` solves this problem by catching data corruption inside QEMU the first
time bad data is read and reporting the disk sector that is corrupted.
-== How it works ==
+How it works
+------------
-The blkverify protocol has two child block devices, the "test" device and the
+The ``blkverify`` protocol has two child block devices, the "test" device and the
"raw" device. Read/write operations are mirrored to both devices so their
state should always be in sync.
@@ -25,13 +28,14 @@ contents to the "test" image. The idea is that the "raw" device will handle
read/write operations correctly and not corrupt data. It can be used as a
reference for comparison against the "test" device.
-After a mirrored read operation completes, blkverify will compare the data and
+After a mirrored read operation completes, ``blkverify`` will compare the data and
raise an error if it is not identical. This makes it possible to catch the
first instance where corrupt data is read.
-== Example ==
+Example
+-------
-Imagine raw.img has 0xcd repeated throughout its first sector:
+Imagine raw.img has 0xcd repeated throughout its first sector::
$ ./qemu-io -c 'read -v 0 512' raw.img
00000000: cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd ................
@@ -42,7 +46,7 @@ Imagine raw.img has 0xcd repeated throughout its first sector:
read 512/512 bytes at offset 0
512.000000 bytes, 1 ops; 0.0000 sec (97.656 MiB/sec and 200000.0000 ops/sec)
-And test.img is corrupt, its first sector is zeroed when it shouldn't be:
+And test.img is corrupt, its first sector is zeroed when it shouldn't be::
$ ./qemu-io -c 'read -v 0 512' test.img
00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
@@ -53,17 +57,17 @@ And test.img is corrupt, its first sector is zeroed when it shouldn't be:
read 512/512 bytes at offset 0
512.000000 bytes, 1 ops; 0.0000 sec (81.380 MiB/sec and 166666.6667 ops/sec)
-This error is caught by blkverify:
+This error is caught by ``blkverify``::
$ ./qemu-io -c 'read 0 512' blkverify:a.img:b.img
blkverify: read sector_num=0 nb_sectors=4 contents mismatch in sector 0
-A more realistic scenario is verifying the installation of a guest OS:
+A more realistic scenario is verifying the installation of a guest OS::
$ ./qemu-img create raw.img 16G
$ ./qemu-img create -f qcow2 test.qcow2 16G
$ ./qemu-system-x86_64 -cdrom debian.iso \
-drive file=blkverify:raw.img:test.qcow2
-If the installation is aborted when blkverify detects corruption, use qemu-io
+If the installation is aborted when ``blkverify`` detects corruption, use ``qemu-io``
to explore the contents of the disk image at the sector in question.
@@ -15,3 +15,4 @@ testing infrastructure.
ci
fuzzing
blkdebug
+ blkverify