aboutsummaryrefslogtreecommitdiff
path: root/block.c
AgeCommit message (Collapse)Author
2017-02-28block: Add Error parameter to bdrv_append()Kevin Wolf
Aborting on error in bdrv_append() isn't correct. This patch fixes it and lets the callers handle failures. Test case 085 needs a reference output update. This is caused by the reversed order of bdrv_set_backing_hd() and change_parent_backing_link() in bdrv_append(): When the backing file of the new node is set, the parent nodes are still pointing to the old top, so the backing blocker is now initialised with the node name rather than the BlockBackend name. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Add Error parameter to bdrv_set_backing_hd()Kevin Wolf
Not all callers of bdrv_set_backing_hd() know for sure that attaching the backing file will be allowed by the permission system. Return the error from the function rather than aborting. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Assertions for resize permissionKevin Wolf
This adds an assertion that ensures that the necessary resize permission has been granted before bdrv_truncate() is called. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Allow backing file links in change_parent_backing_link()Kevin Wolf
Now that the backing file child role implements .attach/.detach callbacks, nothing prevents us from modifying the graph even if that involves changing backing file links. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: BdrvChildRole.attach/detach() callbacksKevin Wolf
Backing files are somewhat special compared to other kinds of children because they are attached and detached using bdrv_set_backing_hd() rather than the normal set of functions, which does a few more things like setting backing blockers, toggling the BDRV_O_NO_BACKING flag, setting parent_bs->backing_file, etc. These special features are a reason why change_parent_backing_link() can't handle backing files yet. With abstracting the additional features into .attach/.detach callbacks, we get a step closer to a function that can actually deal with this. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Fix pending requests check in bdrv_append()Kevin Wolf
bdrv_append() cares about isolation of the node that it modifies, but not about activity in some subtree below it. Instead of using the recursive bdrv_requests_pending(), directly check bs->in_flight, which considers only the node in question. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Add BdrvChildRole.stay_at_nodeKevin Wolf
When the parents' child links are updated in bdrv_append() or bdrv_replace_in_backing_chain(), this should affect all child links of BlockBackends or other nodes, but not on child links held for other purposes (like for setting permissions). This patch allows to control the behaviour per BdrvChildRole. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Include details on permission errors in messageKevin Wolf
Instead of just telling that there was some conflict, we can be specific and tell which permissions were in conflict and which way the conflict is. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Add BdrvChildRole.get_parent_desc()Kevin Wolf
For meaningful error messages in the permission system, we need to get some human-readable description of the parent of a BdrvChild. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Add error parameter to blk_insert_bs()Kevin Wolf
Now that blk_insert_bs() requests the BlockBackend permissions for the node it attaches to, it can fail. Instead of aborting, pass the errors to the callers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Add permissions to blk_new()Kevin Wolf
We want every user to be specific about the permissions it needs, so we'll pass the initial permissions as parameters to blk_new(). A user only needs to call blk_set_perm() if it wants to change the permissions after the fact. The permissions are stored in the BlockBackend and applied whenever a BlockDriverState should be attached in blk_insert_bs(). This does not include actually choosing the right set of permissions everywhere yet. Instead, the usual FIXME comment is added to each place and will be addressed in individual patches. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Request real permissions in bdrv_attach_child()Kevin Wolf
Now that all block drivers with children tell us what permissions they need from each of their children, bdrv_attach_child() can use this information and make the right requirements while trying to attach new children. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Require .bdrv_child_perm() with child nodesKevin Wolf
All block drivers that can have child nodes implement .bdrv_child_perm() now. Make this officially a requirement by asserting that only drivers without children can omit .bdrv_child_perm(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28vvfat: Implement .bdrv_child_perm()Kevin Wolf
vvfat is the last remaining driver that can have children, but doesn't implement .bdrv_child_perm() yet. The default handlers aren't suitable here, so let's implement a very simple driver-specific one that protects the internal child from being used by other users as good as our permissions permit. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Default .bdrv_child_perm() for format driversKevin Wolf
Almost all format drivers have the same characteristics as far as permissions are concerned: They have one or more children for storing their own data and, more importantly, metadata (can be written to and grow even without external write requests, must be protected against other writers and present consistent data) and optionally a backing file (this is just data, so like for a filter, it only depends on what the parent nodes need). This provides a default implementation that can be shared by most of our format drivers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Default .bdrv_child_perm() for filter driversKevin Wolf
Most filters need permissions related to read and write for their children, but only if the node has a parent that wants to use the same operation on the filter. The same is true for resize. This adds a default implementation that simply forwards all necessary permissions to all children of the node and leaves the other permissions unchanged. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Involve block drivers in permission grantingKevin Wolf
In many cases, the required permissions of one node on its children depend on what its parents require from it. For example, the raw format or most filter drivers only need to request consistent reads if that's something that one of their parents wants. In order to achieve this, this patch introduces two new BlockDriver callbacks. The first one lets drivers first check (recursively) whether the requested permissions can be set; the second one actually sets the new permission bitmask. Also add helper functions that drivers can use in their implementation of the callbacks to update their permissions on a specific child. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28block: Let callers request permissions when attaching a child nodeKevin Wolf
When attaching a node as a child to a new parent, the required and shared permissions for this parent are checked against all other parents of the node now, and an error is returned if there is a conflict. This allows error returns to a function that previously always succeeded, and the same is true for quite a few callers and their callers. Converting all of them within the same patch would be too much, so for now everyone tells that they don't need any permissions and allow everyone else to do anything. This way we can use &error_abort initially and convert caller by caller to pass actual permission requirements and implement error handling. All these places are marked with FIXME comments and it will be the job of the next patches to clean them up again. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28block: Add Error argument to bdrv_attach_child()Kevin Wolf
It will have to return an error soon, so prepare the callers for it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com>
2017-02-26Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into stagingPeter Maydell
Block layer patches # gpg: Signature made Fri 24 Feb 2017 18:08:26 GMT # gpg: using RSA key 0x7F09B272C88F2FD6 # gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" # Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6 * remotes/kevin/tags/for-upstream: tests: Use opened block node for block job tests vvfat: Use opened node as backing file block: Add bdrv_new_open_driver() block: Factor out bdrv_open_driver() block: Use BlockBackend for image probing block: Factor out bdrv_open_child_bs() block: Attach bs->file only during .bdrv_open() block: Pass BdrvChild to bdrv_truncate() mirror: Resize active commit base in mirror_run() qcow2: Use BB for resizing in qcow2_amend_options() blockdev: Use BlockBackend to resize in qmp_block_resize() iotests: Fix another race in 030 qemu-img: Improve documentation for PREALLOC_MODE_FALLOC qemu-img: Truncate before full preallocation qemu-img: Add tests for raw image preallocation qemu-img: Do not truncate before preallocation qemu-iotests: redirect nbd server stdout to /dev/null qemu-iotests: add ability to exclude certain protocols from tests qemu-iotests: Test 137 only supports 'file' protocol Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-24block: Add bdrv_new_open_driver()Kevin Wolf
This function allows to create more or less normal BlockDriverStates even for BlockDrivers that aren't globally registered (e.g. helper filters for block jobs). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-24block: Factor out bdrv_open_driver()Kevin Wolf
This is a function that doesn't do any option parsing, but just does some basic BlockDriverState setup and calls the .bdrv_open() function of the block driver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-24block: Use BlockBackend for image probingKevin Wolf
This fixes the use of a parent-less BdrvChild in bdrv_open_inherit() by converting it into a BlockBackend. Which is exactly what it should be, image probing is an external, standalone user of a node. The requests can't be considered to originate from the format driver node because that one isn't even opened yet. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-24block: Factor out bdrv_open_child_bs()Kevin Wolf
This is the part of bdrv_open_child() that opens a BDS with option inheritance, but doesn't attach it as a child to the parent yet. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-24block: Attach bs->file only during .bdrv_open()Kevin Wolf
The way that attaching bs->file worked was a bit unusual in that it was the only child that would be attached to a node which is not opened yet. Because of this, the block layer couldn't know yet which permissions the driver would eventually need. This patch moves the point where bs->file is attached to the beginning of the individual .bdrv_open() implementations, so drivers already know what they are going to do with the child. This is also more consistent with how driver-specific children work. For a moment, bdrv_open() gets its own BdrvChild to perform image probing, but instead of directly assigning this BdrvChild to the BDS, it becomes a temporary one and the node name is passed as an option to the drivers, so that they can simply use bdrv_open_child() to create another reference for their own use. This duplicated child for (the not opened yet) bs is not the final state, a follow-up patch will change the image probing code to use a BlockBackend, which is completely independent of bs. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-24block: Pass BdrvChild to bdrv_truncate()Kevin Wolf
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-22Don't check qobject_type() before qobject_to_qdict()Markus Armbruster
qobject_to_qdict(obj) returns NULL when obj isn't a QDict. Check that instead of qobject_type(obj) == QTYPE_QDICT. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1487363905-9480-8-git-send-email-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2017-02-12block: bdrv_invalidate_cache: invalidate children firstVladimir Sementsov-Ogievskiy
Current implementation invalidates firstly parent bds and then its children. This leads to the following bug: after incoming migration, in bdrv_invalidate_cache_all: 1. invalidate parent bds - reopen it with BDRV_O_INACTIVE cleared 2. child is not yet invalidated 3. parent check that its BDRV_O_INACTIVE is cleared 4. parent writes to child 5. assert in bdrv_co_pwritev, as BDRV_O_INACTIVE is set for child This patch fixes it by just changing invalidate sequence: invalidate children first. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-id: 20170131112308.54189-1-vsementsov@virtuozzo.com Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-02-12block: check full backing filename when searching protocol filenamesJeff Cody
In bdrv_find_backing_image(), if we are searching an image for a backing file that contains a protocol, we currently only compare unmodified paths. However, some management software will change the backing filename to be a relative filename in a path. QEMU is able to handle this fine, because internally it will use path_combine to put together the full protocol URI. However, this can lead to an inability to match an image during a QAPI command that needs to use bdrv_find_backing_image() to find the image, when it is searched by the full URI. When searching for a protocol filename, if the straight comparison fails, this patch will also compare against the full backing filename to see if that is a match. Signed-off-by: Jeff Cody <jcody@redhat.com> Message-id: c2d025adca8a2b665189e6f4cf080f44126d0b6b.1485392617.git.jcody@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-01-31trace: switch to modular code generation for sub-directoriesDaniel P. Berrange
Introduce rules in the top level Makefile that are able to generate trace.[ch] files in every subdirectory which has a trace-events file. The top level directory is handled specially, so instead of creating trace.h, it creates trace-root.h. This allows sub-directories to include the top level trace-root.h file, without ambiguity wrt to the trace.g file in the current sub-dir. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170125161417.31949-7-berrange@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-24block: remove dead checkPaolo Bonzini
options must be non-NULL here, because a NULL value is replaced with qdict_new earlier in the function. Reported by Coverity. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-11-11block: Emit modules in bdrv_iterate_format()Max Reitz
Some block drivers may not be loaded yet, but qemu supports them nonetheless. bdrv_iterate_format() should report them, too. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20161012204907.25941-3-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-11-11block: Fix bdrv_iterate_format() sortingMax Reitz
bdrv_iterate_format() did not actually sort the formats by name but by "pointer interpreted as string". That is probably not what we intended to do, so fix it (by changing qsort_strcmp() so it matches the example from qsort()'s manual page). Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20161012204907.25941-2-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-10-31block: Support streaming to an intermediate layerAlberto Garcia
This makes sure that the image we are streaming into is open in read-write mode during the operation. Operation blockers are also set in all intermediate nodes, since they will be removed from the chain afterwards. Finally, this also unblocks the stream operation in backing files. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-31block: Pause all jobs during bdrv_reopen_multiple()Alberto Garcia
When a BlockDriverState is about to be reopened it can trigger certain operations that need to write to disk. During this process a different block job can be woken up. If that block job completes and also needs to call bdrv_reopen() it can happen that it needs to do it on the same BlockDriverState that is still in the process of being reopened. This can have fatal consequences, like in this example: 1) Block job A starts and sleeps after a while. 2) Block job B starts and tries to reopen node1 (a qcow2 file). 3) Reopening node1 means flushing and replacing its qcow2 cache. 4) While the qcow2 cache is being flushed, job A wakes up. 5) Job A completes and reopens node1, replacing its cache. 6) Job B resumes, but the cache that was being flushed no longer exists. This patch splits the bdrv_drain_all() call to keep all block jobs paused during bdrv_reopen_multiple(), so that step 4 can never happen and the operation is safe. Note that this scenario can only happen if both bdrv_reopen() calls are made by block jobs on the same backing chain. Otherwise there's no chance that the same BlockDriverState appears in both reopen queues. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-28block: only call aio_poll on the current thread's AioContextPaolo Bonzini
aio_poll is not thread safe; for example bdrv_drain can hang if the last in-flight I/O operation is completed in the I/O thread after the main thread has checked bs->in_flight. The bug remains latent as long as all of it is called within aio_context_acquire/aio_context_release, but this will change soon. To fix this, if bdrv_drain is called from outside the I/O thread, signal the main AioContext through a dummy bottom half. The event loop then only runs in the I/O thread. Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1477565348-5458-18-git-send-email-pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
2016-10-28block: prepare bdrv_reopen_multiple to release AioContextPaolo Bonzini
After the next patch bdrv_drain_all will have to be called without holding any AioContext. Prepare to do this by adding an AioContext argument to bdrv_reopen_multiple. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1477565348-5458-15-git-send-email-pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
2016-10-07block: Add qdev ID to DEVICE_TRAY_MOVEDKevin Wolf
The event currently only contains the BlockBackend name. However, with anonymous BlockBackends, this is always the empty string. Add the qdev ID (or if none was given, the QOM path) so that the user can still see which device caused the event. Event generation has to be moved from bdrv_eject() to the BlockBackend because the BDS doesn't know the attached device, but that's easy because blk_eject() is the only user of it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-10-07block: Add bdrv_runtime_opts to query-command-line-optionsKevin Wolf
Recently we moved a few options from QemuOptsLists in blockdev.c to bdrv_runtime_opts in block.c in order to make them accissble using blockdev-add. However, this has the side effect that these options are missing from query-command-line-options now, and libvirt consequently disables the corresponding feature. This problem was reported as a regression for the 'discard' option, introduced in commit 818584a4. However, it is more general than that. Fix it by adding bdrv_runtime_opts to the list of QemuOptsLists that are returned in query-command-line-options. For the future, libvirt is advised to use QMP schema introspection for block device options. Reported-by: Michal Privoznik <mprivozn@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Tested-by: Michal Privoznik <mprivozn@redhat.com> Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-09-29block: Move 'discard' option to bdrv_open_common()Kevin Wolf
This enables its use for nested child nodes. The compatibility between the 'discard' and 'detect-zeroes' setting is checked in bdrv_open_common() now as the former setting isn't available before calling bdrv_open() any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-29block: Parse 'detect-zeroes' in bdrv_open_common()Kevin Wolf
Amongst others, this means that you can now use the 'detect-zeroes' option for non-top-level nodes in blockdev-add, like the QAPI schema promises. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-23block: Don't queue the same BDS twice in bdrv_reopen_queue_child()Alberto Garcia
bdrv_reopen_queue_child() assumes that a BlockDriverState is never added twice to BlockReopenQueue. That's however not the case: commit_start() adds 'base' (and its children) to a new reopen queue, and then 'overlay_bs' (and its children, which include 'base') to the same queue. The effect of this is that the first set of options is ignored and overriden by the second. We fixed this by swapping the order in which both BDSs were added to the queue in 3db2bd5508c86a1605258bc77c9672d93b5c350e. This patch checks if a BDS is already in the reopen queue and keeps its options. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-23block: Add "read-only" to the options QDictAlberto Garcia
This adds the "read-only" option to the QDict. One important effect of this change is that when a child inherits options from its parent, the existing "read-only" mode can be preserved if it was explicitly set previously. This addresses scenarios like this: [E] <- [D] <- [C] <- [B] <- [A] In this case, if we reopen [D] with read-only=off, and later reopen [B], then [D] will not inherit read-only=on from its parent during the bdrv_reopen_queue_child() stage. The BDRV_O_RDWR flag is not removed yet, but its keep in sync with the value of the "read-only" option. Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-23block: Update bs->open_flags earlier in bdrv_open_common()Alberto Garcia
We're only doing this immediately before opening the image, but bs->open_flags is used earlier in the function. At the moment this is not causing problems because none of the checked flags are modified by update_flags_from_options(), but this will change when we introduce the "read-only" option. This patch calls update_flags_from_options() at the beginning of the function, immediately after creating the QemuOpts. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-23block: Set BDRV_O_ALLOW_RDWR and snapshot_options before storing the flagsAlberto Garcia
If an image is opened with snapshot=on, its flags are modified by bdrv_backing_options() and then bs->open_flags is updated accordingly. This last step is unnecessary if we calculate the new flags before setting bs->open_flags. Soon we'll introduce the "read-only" option, and then we'll need to be able to modify its value in the QDict when snapshot=on. This is more cumbersome if bs->options is already set. This patch simplifies that. Other than that, there are no semantic changes. Although it might seem that bs->options can have a different value now because it is stored after calling bdrv_backing_options(), this call doesn't actually modify them in this scenario. The code that sets BDRV_O_ALLOW_RDWR is also moved for the same reason. Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-23block: Remove bdrv_is_snapshotAlberto Garcia
This is unnecessary and has been unused since 5433c24f0f9306c82ad9bcc. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-20blockdev: Add dynamic module loading for block driversMarc Mari
Extend the current module interface to allow for block drivers to be loaded dynamically on request. The only block drivers that can be converted into modules are the drivers that don't perform any init operation except for registering themselves. In addition, only the protocol drivers are being modularized, as they are the only ones which see significant performance benefits. The format drivers do not generally link to external libraries, so modularizing them is of no benefit from a performance perspective. All the necessary module information is located in a new structure found in module_block.h This spoils the purpose of 5505e8b76f (block/dmg: make it modular). Before this patch, if module build is enabled, block-dmg.so is linked to libbz2, whereas the main binary is not. In downstream, theoretically, it means only the qemu-block-extra package depends on libbz2, while the main QEMU package needn't to. With this patch, we (temporarily) change the case so that the main QEMU depends on libbz2 again. Signed-off-by: Marc MarĂ­ <markmb@redhat.com> Signed-off-by: Colin Lord <clord@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1471008424-16465-4-git-send-email-clord@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> [mreitz: Do a signed comparison against the length of block_driver_modules[], so it will not cause a compile error when empty] Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-09-13block: unblock backup operations in backing fileWen Congyang
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com> Signed-off-by: Wang WeiWei <wangww.fnst@cn.fujitsu.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Kashyap Chamarthy <kchamart@redhat.com> Message-id: 1469602913-20979-2-git-send-email-xiecl.fnst@cn.fujitsu.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-09-05nbd-server: Use a separate BlockBackendKevin Wolf
The builtin NBD server uses its own BlockBackend now instead of reusing the monitor/guest device one. This means that it has its own writethrough setting now. The builtin NBD server always uses writeback caching now regardless of whether the guest device has WCE enabled. qemu-nbd respects the cache mode given on the command line. We still need to keep a reference to the monitor BB because we put an eject notifier on it, but we don't use it for any I/O. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-07-19block: remove extra condition in bdrv_can_write_zeroes_with_unmapDenis V. Lunev
All .bdrv_co_write_zeroes callbacks nowadays work perfectly even with backing store attached. If future new callbacks would be unable to do that - they have a chance to block this in bdrv_get_info(). Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1468503209-19498-6-git-send-email-den@openvz.org CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> CC: Jeff Cody <jcody@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com>