docs/interop/nbd.txt | 38 +++++ qapi/block.json | 23 +++ include/block/nbd.h | 11 +- blockdev-nbd.c | 23 +++ nbd/common.c | 2 + nbd/server.c | 385 ++++++++++++++++++++++++++++++++++++++++++++------- MAINTAINERS | 1 + nbd/trace-events | 1 + tests/.gitignore | 93 +------------ 9 files changed, 433 insertions(+), 144 deletions(-) create mode 100644 docs/interop/nbd.txt
The following changes since commit 46012db666990ff2eed1d3dc199ab8006439a93b:
Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20180619' into staging (2018-06-20 09:51:30 +0100)
are available in the Git repository at:
git://repo.or.cz/qemu/ericb.git tags/pull-nbd-2018-06-20-v2
for you to fetch changes up to bc37b06a5cde24fb24c2a2cc44dd86756034ba9d:
nbd/server: introduce NBD_CMD_CACHE (2018-06-21 09:41:39 -0500)
Only sending the new patches (2, 9) and the changed patch (6, was 5/7
in v1)
----------------------------------------------------------------
nbd patches for 2018-06-20
Add experimental x-nbd-server-add-bitmap to expose a disabled
bitmap over NBD, in preparation for a pull model incremental
backup scheme. Also fix a corner case protocol issue with
NBD_CMD_BLOCK_STATUS, and add new NBD_CMD_CACHE.
- Eric Blake: tests: Simplify .gitignore
- Eric Blake: nbd/server: Reject 0-length block status request
- Vladimir Sementsov-Ogievskiy: 0/6 NBD export bitmaps
- Vladimir Sementsov-Ogievskiy: nbd/server: introduce NBD_CMD_CACHE
----------------------------------------------------------------
Eric Blake (2):
tests: Simplify .gitignore
nbd/server: Reject 0-length block status request
Vladimir Sementsov-Ogievskiy (7):
nbd/server: fix trace
nbd/server: refactor NBDExportMetaContexts
nbd/server: add nbd_meta_empty_or_pattern helper
nbd/server: implement dirty bitmap export
qapi: new qmp command nbd-server-add-bitmap
docs/interop: add nbd.txt
nbd/server: introduce NBD_CMD_CACHE
docs/interop/nbd.txt | 38 +++++
qapi/block.json | 23 +++
include/block/nbd.h | 11 +-
blockdev-nbd.c | 23 +++
nbd/common.c | 2 +
nbd/server.c | 385 ++++++++++++++++++++++++++++++++++++++++++++-------
MAINTAINERS | 1 +
nbd/trace-events | 1 +
tests/.gitignore | 93 +------------
9 files changed, 433 insertions(+), 144 deletions(-)
create mode 100644 docs/interop/nbd.txt
--
2.14.4
On 21 June 2018 at 15:57, Eric Blake <eblake@redhat.com> wrote: > The following changes since commit 46012db666990ff2eed1d3dc199ab8006439a93b: > > Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20180619' into staging (2018-06-20 09:51:30 +0100) > > are available in the Git repository at: > > git://repo.or.cz/qemu/ericb.git tags/pull-nbd-2018-06-20-v2 > > for you to fetch changes up to bc37b06a5cde24fb24c2a2cc44dd86756034ba9d: > > nbd/server: introduce NBD_CMD_CACHE (2018-06-21 09:41:39 -0500) > > Only sending the new patches (2, 9) and the changed patch (6, was 5/7 > in v1) > > ---------------------------------------------------------------- > nbd patches for 2018-06-20 > > Add experimental x-nbd-server-add-bitmap to expose a disabled > bitmap over NBD, in preparation for a pull model incremental > backup scheme. Also fix a corner case protocol issue with > NBD_CMD_BLOCK_STATUS, and add new NBD_CMD_CACHE. > > - Eric Blake: tests: Simplify .gitignore > - Eric Blake: nbd/server: Reject 0-length block status request > - Vladimir Sementsov-Ogievskiy: 0/6 NBD export bitmaps > - Vladimir Sementsov-Ogievskiy: nbd/server: introduce NBD_CMD_CACHE > Applied, thanks. -- PMM
On 22 June 2018 at 10:57, Peter Maydell <peter.maydell@linaro.org> wrote:
> On 21 June 2018 at 15:57, Eric Blake <eblake@redhat.com> wrote:
>> ----------------------------------------------------------------
>> nbd patches for 2018-06-20
>>
>> Add experimental x-nbd-server-add-bitmap to expose a disabled
>> bitmap over NBD, in preparation for a pull model incremental
>> backup scheme. Also fix a corner case protocol issue with
>> NBD_CMD_BLOCK_STATUS, and add new NBD_CMD_CACHE.
>>
>> - Eric Blake: tests: Simplify .gitignore
>> - Eric Blake: nbd/server: Reject 0-length block status request
>> - Vladimir Sementsov-Ogievskiy: 0/6 NBD export bitmaps
>> - Vladimir Sementsov-Ogievskiy: nbd/server: introduce NBD_CMD_CACHE
>>
> Applied, thanks.
...patchew seems to be unhappy, though, eg
https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg06559.html
has an unrelated patchset failing with:
/tmp/qemu-test/src/nbd/server.c: In function 'nbd_trip':
/tmp/qemu-test/src/nbd/server.c:1980:19: error: 'end' may be used uninitialized
in this function [-Werror=maybe-uninitialized]
*length = end - offset;
~~~~^~~~~~~~
/tmp/qemu-test/src/nbd/server.c:1940:30: note: 'end' was declared here
uint64_t begin = offset, end;
^~~
cc1: all warnings being treated as errors
thanks
-- PMM
On 06/22/2018 06:43 AM, Peter Maydell wrote:
> On 22 June 2018 at 10:57, Peter Maydell <peter.maydell@linaro.org> wrote:
>> On 21 June 2018 at 15:57, Eric Blake <eblake@redhat.com> wrote:
>>> ----------------------------------------------------------------
>>> nbd patches for 2018-06-20
>>>
>>> Add experimental x-nbd-server-add-bitmap to expose a disabled
>>> bitmap over NBD, in preparation for a pull model incremental
>>> backup scheme. Also fix a corner case protocol issue with
>>> NBD_CMD_BLOCK_STATUS, and add new NBD_CMD_CACHE.
>>>
>>> - Eric Blake: tests: Simplify .gitignore
>>> - Eric Blake: nbd/server: Reject 0-length block status request
>>> - Vladimir Sementsov-Ogievskiy: 0/6 NBD export bitmaps
>>> - Vladimir Sementsov-Ogievskiy: nbd/server: introduce NBD_CMD_CACHE
>>>
>> Applied, thanks.
>
> ...patchew seems to be unhappy, though, eg
> https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg06559.html
> has an unrelated patchset failing with:
>
> /tmp/qemu-test/src/nbd/server.c: In function 'nbd_trip':
> /tmp/qemu-test/src/nbd/server.c:1980:19: error: 'end' may be used uninitialized
> in this function [-Werror=maybe-uninitialized]
> *length = end - offset;
> ~~~~^~~~~~~~
Uurgh. It's a false positive (the compiler is complaining that the
variable is uninitialized, which can only happen if the while loop is
not executed; but the preconditions guarantee the loop executes at least
once). The assert() that I added was enough to silence gcc 7.3.1 on my
Fedora 27 system, but docker-mingw@fedora is using
gcc-8.1.1-1.fc28.x86_64. This should silence things (another way to
silence would be rewriting while{} into do{}while). I'll submit this as
a formal patch if I can reproduce the problem/fix on docker.
diff --git i/nbd/server.c w/nbd/server.c
index 94137fbfe8f..2379f82d5d4 100644
--- i/nbd/server.c
+++ w/nbd/server.c
@@ -1968,7 +1968,7 @@ static unsigned int
bitmap_to_extents(BdrvDirtyBitmap *bitmap, uint64_t offset,
unsigned int nb_extents,
bool dont_fragment)
{
- uint64_t begin = offset, end;
+ uint64_t begin = offset, end = offset;
uint64_t overall_end = offset + *length;
unsigned int i = 0;
BdrvDirtyBitmapIter *it;
@@ -2008,6 +2008,7 @@ static unsigned int
bitmap_to_extents(BdrvDirtyBitmap *bitmap, uint64_t offset,
bdrv_dirty_bitmap_unlock(bitmap);
+ assert(offset > end);
*length = end - offset;
return i;
}
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
On 22 June 2018 at 13:12, Eric Blake <eblake@redhat.com> wrote:
> Uurgh. It's a false positive (the compiler is complaining that the variable
> is uninitialized, which can only happen if the while loop is not executed;
> but the preconditions guarantee the loop executes at least once). The
> assert() that I added was enough to silence gcc 7.3.1 on my Fedora 27
> system, but docker-mingw@fedora is using gcc-8.1.1-1.fc28.x86_64. This
> should silence things (another way to silence would be rewriting while{}
> into do{}while). I'll submit this as a formal patch if I can reproduce the
> problem/fix on docker.
Huh. I had thought this was an old-gcc problem, not a new-gcc
one. Might be worth submitting to the gcc folks as a regression...
thanks
-- PMM
On 06/22/2018 07:13 AM, Peter Maydell wrote:
> On 22 June 2018 at 13:12, Eric Blake <eblake@redhat.com> wrote:
>> Uurgh. It's a false positive (the compiler is complaining that the variable
>> is uninitialized, which can only happen if the while loop is not executed;
>> but the preconditions guarantee the loop executes at least once). The
>> assert() that I added was enough to silence gcc 7.3.1 on my Fedora 27
>> system, but docker-mingw@fedora is using gcc-8.1.1-1.fc28.x86_64. This
>> should silence things (another way to silence would be rewriting while{}
>> into do{}while). I'll submit this as a formal patch if I can reproduce the
>> problem/fix on docker.
>
> Huh. I had thought this was an old-gcc problem, not a new-gcc
> one. Might be worth submitting to the gcc folks as a regression...
Hmm, I couldn't quickly reproduce it with a direct gcc on Fedora 28; and
I don't know docker well enough to know if the cross-gcc used in
docker-mingw@fedora is a different version than the native gcc-8.1.1
listed in the installed packages list (the patchew output doesn't list
the version of x86_64-w64-mingw32-gcc). Thus, I can't tell if it is a
recent gcc regression or merely an old-gcc issue. But I can confirm
that 'make docker-test-mingw@fedora' reproduced the problem without my
cleanup patch, and that my cleanup patch now in master made that happy
again.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
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