aboutsummaryrefslogtreecommitdiff
path: root/qobject/block-qdict.c
AgeCommit message (Collapse)Author
2022-03-21block-qdict: Fix -Werror=maybe-uninitialized build failureMurilo Opsfelder Araujo
Building QEMU on Fedora 37 (Rawhide Prerelease) ppc64le failed with the following error: $ ../configure --prefix=/usr/local/qemu-disabletcg --target-list=ppc-softmmu,ppc64-softmmu --disable-tcg --disable-linux-user ... $ make -j$(nproc) ... In file included from /root/qemu/include/qapi/qmp/qdict.h:16, from /root/qemu/include/block/qdict.h:13, from ../qobject/block-qdict.c:11: /root/qemu/include/qapi/qmp/qobject.h: In function ‘qdict_array_split’: /root/qemu/include/qapi/qmp/qobject.h:49:17: error: ‘subqdict’ may be used uninitialized [-Werror=maybe-uninitialized] 49 | typeof(obj) _obj = (obj); \ | ^~~~ ../qobject/block-qdict.c:227:16: note: ‘subqdict’ declared here 227 | QDict *subqdict; | ^~~~~~~~ cc1: all warnings being treated as errors Fix build failure by expanding the ternary operation. Tested with `make check-unit` (the check-block-qdict test passed). Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Hanna Reitz <hreitz@redhat.com> Cc: Markus Armbruster <armbru@redhat.com> Message-Id: <20220311221634.58288-1-muriloo@linux.ibm.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-10-26qobject: Catch another straggler for use of qdict_put_str()Philippe Mathieu-Daudé
Patch created mechanically by rerunning: $ spatch --sp-file scripts/coccinelle/qobject.cocci \ --macro-file scripts/cocci-macro-file.h \ --dir . --in-place Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Markus Armbruster <armbru@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <20180705155811.20366-2-f4bug@amsat.org> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2018-08-15qdict: Make qdict_extract_subqdict() accept dst = NULLAlberto Garcia
This function extracts all options from a QDict starting with a certain prefix and puts them in a new QDict. We'll have a couple of cases where we simply want to discard those options instead of copying them, and that's what this patch does. Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-29block-qdict: Pacify Coverity after commit f1b34a248e9Markus Armbruster
Commit f1b34a248e9 replaced less-than-obvious test in qdict_flatten_qdict() by the obvious one. Sadly, it made something else non-obvious: the fact that @new_key passed to qdict_put_obj() can't be null, because that depends on the function's precondition (target == qdict) == !prefix. Tweak the function some more to help Coverity and human readers alike. Fixes: CID 1393620 Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-22qdict: Make qdict_flatten() shallow-clone-friendlyMax Reitz
In its current form, qdict_flatten() removes all entries from nested QDicts that are moved to the root QDict. It is completely sufficient to remove all old entries from the root QDict, however. If the nested dicts have a refcount of 1, this will automatically delete them, too. And if they have a greater refcount, we probably do not want to modify them in the first place. The latter observation means that it was currently (in general) impossible to qdict_flatten() a shallowly cloned dict because that would empty nested QDicts in the original dict as well. This patch changes this, so you can now use qdict_flatten(qdict_shallow_clone(dict)) to get a flattened copy without disturbing the original. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20180611205203.2624-7-mreitz@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-06-15block: Fix -blockdev / blockdev-add for empty objects and arraysMarkus Armbruster
-blockdev and blockdev-add silently ignore empty objects and arrays in their argument. That's because qmp_blockdev_add() converts the argument to a flat QDict, and qdict_flatten() eats empty QDict and QList members. For instance, we ignore an empty BlockdevOptions member @cache. No real harm, as absent means the same as empty there. Thus, the flaw puts an artificial restriction on the QAPI schema: we can't have potentially empty objects and arrays within BlockdevOptions, except when they're optional and "empty" has the same meaning as "absent". Our QAPI schema satisfies this restriction (I checked), but it's a trap for the unwary, and a temptation to employ awkward workarounds for the wary. Let's get rid of it. Change qdict_flatten() and qdict_crumple() to treat empty dictionaries and lists exactly like scalars. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15block-qdict: Simplify qdict_is_list() someMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15block-qdict: Clean up qdict_crumple() a bitMarkus Armbruster
When you mix scalar and non-scalar keys, whether you get an "already set as scalar" or an "already set as dict" error depends on qdict iteration order. Neither message makes much sense. Replace by ""Cannot mix scalar and non-scalar keys". This is similar to the message we get for mixing list and non-list keys. I find qdict_crumple()'s first loop hard to understand. Rearrange it and add a comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15block-qdict: Tweak qdict_flatten_qdict(), qdict_flatten_qlist()Markus Armbruster
qdict_flatten_qdict() skips copying scalars from @qdict to @target when the two are the same. Fair enough, but it uses a non-obvious test for "same". Replace it by the obvious one. While there, improve comments. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15block-qdict: Simplify qdict_flatten_qdict()Markus Armbruster
There's no need to restart the loop. We don't elsewhere, e.g. in qdict_extract_subqdict(), qdict_join() and qemu_opts_absorb_qdict(). Simplify accordingly. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15block: Factor out qobject_input_visitor_new_flat_confused()Markus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15block: Fix -blockdev for certain non-string scalarsMarkus Armbruster
Configuration flows through the block subsystem in a rather peculiar way. Configuration made with -drive enters it as QemuOpts. Configuration made with -blockdev / blockdev-add enters it as QAPI type BlockdevOptions. The block subsystem uses QDict, QemuOpts and QAPI types internally. The precise flow is next to impossible to explain (I tried for this commit message, but gave up after wasting several hours). What I can explain is a flaw in the BlockDriver interface that leads to this bug: $ qemu-system-x86_64 -blockdev node-name=n1,driver=nfs,server.type=inet,server.host=localhost,path=/foo/bar,user=1234 qemu-system-x86_64: -blockdev node-name=n1,driver=nfs,server.type=inet,server.host=localhost,path=/foo/bar,user=1234: Internal error: parameter user invalid QMP blockdev-add is broken the same way. Here's what happens. The block layer passes configuration represented as flat QDict (with dotted keys) to BlockDriver methods .bdrv_file_open(). The QDict's members are typed according to the QAPI schema. nfs_file_open() converts it to QAPI type BlockdevOptionsNfs, with qdict_crumple() and a qobject input visitor. This visitor comes in two flavors. The plain flavor requires scalars to be typed according to the QAPI schema. That's the case here. The keyval flavor requires string scalars. That's not the case here. nfs_file_open() uses the latter, and promptly falls apart for members @user, @group, @tcp-syn-count, @readahead-size, @page-cache-size, @debug. Switching to the plain flavor would fix -blockdev, but break -drive, because there the scalars arrive in nfs_file_open() as strings. The proper fix would be to replace the QDict by QAPI type BlockdevOptions in the BlockDriver interface. Sadly, that's beyond my reach right now. Next best would be to fix the block layer to always pass correctly typed QDicts to the BlockDriver methods. Also beyond my reach. What I can do is throw another hack onto the pile: have nfs_file_open() convert all members to string, so use of the keyval flavor actually works, by replacing qdict_crumple() by new function qdict_crumple_for_keyval_qiv(). The pattern "pass result of qdict_crumple() to qobject_input_visitor_new_keyval()" occurs several times more: * qemu_rbd_open() Same issue as nfs_file_open(), but since BlockdevOptionsRbd has only string members, its only a latent bug. Fix it anyway. * parallels_co_create_opts(), qcow_co_create_opts(), qcow2_co_create_opts(), bdrv_qed_co_create_opts(), sd_co_create_opts(), vhdx_co_create_opts(), vpc_co_create_opts() These work, because they create the QDict with qemu_opts_to_qdict_filtered(), which creates only string scalars. The function sports a TODO comment asking for better typing; that's going to be fun. Use qdict_crumple_for_keyval_qiv() to be safe. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15qobject: Move block-specific qdict code to block-qdict.cMarkus Armbruster
Pure code motion, except for two brace placements and a comment tweaked to appease checkpatch. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>