10:12 a.m.
The QueryAllocatedBlocks API has (another) frustrating feature. It
can only query whole "chunks" (128 sectors). If the disk size is not
aligned to the chunk size (say the size was 129 sectors) then there's
a bit at the end which cannot be queried. Furthermore, the API gives
an error in this case instead of being helpful:
VixDiskLib_QueryAllocatedBlocks: One of the parameters was invalid
Fixes: https://issues.redhat.com/browse/RHEL-71694
---
tests/Makefile.am | 5 +-
plugins/vddk/worker.c | 43 ++++++++++++-
tests/test-vddk-real-unaligned-chunk.sh | 82 +++++++++++++++++++++++++
3 files changed, 126 insertions(+), 4 deletions(-)
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 29c762b636..713951c741 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -202,7 +202,8 @@ if HAVE_VDDK
check-vddk:
$(MAKE) check TESTS="test-vddk-real.sh \
test-vddk-real-dump-plugin.sh \
- test-vddk-real-create.sh"
+ test-vddk-real-create.sh \
+ test-vddk-real-unaligned-chunk.sh"
endif HAVE_VDDK
#----------------------------------------------------------------------
@@ -1207,6 +1208,7 @@ TESTS += \
test-vddk-password-interactive.sh \
test-vddk-real-create.sh \
test-vddk-real-dump-plugin.sh \
+ test-vddk-real-unaligned-chunk.sh \
test-vddk-real.sh \
test-vddk-reexec.sh \
test-vddk-run.sh \
@@ -1239,6 +1241,7 @@ EXTRA_DIST += \
test-vddk-password-interactive.sh \
test-vddk-real-create.sh \
test-vddk-real-dump-plugin.sh \
+ test-vddk-real-unaligned-chunk.sh \
test-vddk-real.sh \
test-vddk-reexec.sh \
test-vddk-run.sh \
diff --git a/plugins/vddk/worker.c b/plugins/vddk/worker.c
index bc015d1618..12a68d30e4 100644
--- a/plugins/vddk/worker.c
+++ b/plugins/vddk/worker.c
@@ -392,10 +392,11 @@ do_extents (struct command *cmd, struct vddk_handle *h)
const uint64_t offset = cmd->offset;
const bool req_one = cmd->req_one;
struct nbdkit_extents *extents = cmd->ptr;
- uint64_t position, end, start_sector;
+ VixError err;
+ VixDiskLibInfo *info;
+ uint64_t position, start_sector, capacity, last_queryable_sector, end;
position = offset;
- end = offset + count;
/* We can only query whole chunks. Therefore start with the
* first chunk before offset.
@@ -403,8 +404,33 @@ do_extents (struct command *cmd, struct vddk_handle *h)
start_sector =
ROUND_DOWN (offset, VIXDISKLIB_MIN_CHUNK_SIZE * VIXDISKLIB_SECTOR_SIZE)
/ VIXDISKLIB_SECTOR_SIZE;
+
+ /* Get the size of the underlying disk. */
+ VDDK_CALL_START (VixDiskLib_GetInfo, "handle, &info")
+ err = VixDiskLib_GetInfo (h->handle, &info);
+ VDDK_CALL_END (VixDiskLib_GetInfo, 0);
+ if (err != VIX_OK) {
+ VDDK_ERROR (err, "VixDiskLib_GetInfo");
+ return -1;
+ }
+ capacity = info->capacity; /* in sectors! */
+ VDDK_CALL_START (VixDiskLib_FreeInfo, "info")
+ VixDiskLib_FreeInfo (info);
+ VDDK_CALL_END (VixDiskLib_FreeInfo, 0);
+
+ /* Calculate the end that we're going to query, normally this is
+ * offset + count. However since chunks are larger than sectors,
+ * for a disk which has size (capacity) which is not aligned to the
+ * chunk size there is a part of the disk at the end that we can
+ * never query. Reduce 'end' to the maximum possible queryable part
+ * of the disk, and we'll deal with the unaligned bit after the loop
+ * (RHEL-71694).
+ */
+ end = offset + count;
+ last_queryable_sector = ROUND_DOWN (capacity, VIXDISKLIB_MIN_CHUNK_SIZE);
+ end = MIN (end, last_queryable_sector * VIXDISKLIB_SECTOR_SIZE);
+
while (start_sector * VIXDISKLIB_SECTOR_SIZE < end) {
- VixError err;
uint32_t i;
uint64_t nr_chunks, nr_sectors;
VixDiskLibBlockList *block_list;
@@ -474,6 +500,17 @@ do_extents (struct command *cmd, struct vddk_handle *h)
break;
}
+ /* If 'end' spanned beyond the last chunk of the disk, then we
+ * reduced it above to avoid reading a chunk that extends beyond the
+ * end of the underlying disk. We have to synthesize an allocated
+ * block here, which is what VDDK's example code does
+ * (doc/samples/diskLib/vixDiskLibSample.cpp: DoGetAllocatedBlocks).
+ */
+ if (end < offset + count) {
+ if (add_extent (extents, &position, offset + count, false) == -1)
+ return -1;
+ }
+
return 0;
}
diff --git a/tests/test-vddk-real-unaligned-chunk.sh
b/tests/test-vddk-real-unaligned-chunk.sh
new file mode 100755
index 0000000000..28fccd6c88
--- /dev/null
+++ b/tests/test-vddk-real-unaligned-chunk.sh
@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+# nbdkit
+# Copyright Red Hat
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the name of Red Hat nor the names of its contributors may be
+# used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+# Regression test for https://issues.redhat.com/browse/RHEL-71694
+
+source ./functions.sh
+set -e
+set -x
+
+requires_run
+requires test "x$vddkdir" != "x"
+requires test -d "$vddkdir"
+requires test -f "$vddkdir/lib64/libvixDiskLib.so"
+requires qemu-img --version
+requires_nbdinfo
+requires $TRUNCATE --version
+requires dd --version
+requires test -r /dev/urandom
+skip_if_valgrind "because setting LD_LIBRARY_PATH breaks valgrind"
+
+# VDDK > 5.1.1 only supports x86_64.
+if [ `uname -m` != "x86_64" ]; then
+ echo "$0: unsupported architecture"
+ exit 77
+fi
+
+d=vddk-real-unaligned-chunk.d
+cleanup_fn rm -rf $d
+rm -rf $d
+mkdir $d
+
+# Create a vmdk disk which is partially sparse and the size is NOT
+# aligned to 128 sectors (chunk size).
+dd if=/dev/urandom of=$d/test.raw bs=512 count=$(( 3*128 ))
+$TRUNCATE -s $(( (4*128 + 3) * 512)) $d/test.raw
+qemu-img convert -f raw $d/test.raw -O vmdk $d/test.vmdk
+
+# Read the map using VDDK.
+export d
+nbdkit -rfv vddk libdir="$vddkdir" \
+ $PWD/$d/test.vmdk \
+ --run 'nbdinfo --map "$uri" > $d/map'
+cat $d/map
+
+# Note a few features of the expected map. The first 3 chunks (3*128
+# sectors) are allocated, followed by a single hole chunk. Then the
+# last 3 unaligned sectors appear allocated (even though they are not)
+# because we could not read them using the QueryAllocatedBlocks API so
+# we had to assume allocated.
+test "$(cat $d/map)" = "\
+ 0 196608 0 data
+ 196608 65536 3 hole,zero
+ 262144 1536 0 data"
--
2.46.0