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2014-12-12block: Don't add trailing space in "Formating..." messageFam Zheng
Change the message printing code to output a separator for each option string before it instead of after, then we don't one more extra ' ' in the end. To update qemu-iotests output files, most of the times one would just copy the *.out.bad to *.out. With this change we will not have the space disliked by checkpatch.pl. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-id: 1418110684-19528-3-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12vmdk: Fix error for JSON descriptor file namesMax Reitz
If vmdk blindly tries to use path_combine() using bs->file->filename as the base file name, this will result in a bad error message for JSON file names when calling bdrv_open(). It is better to only try bs->file->exact_filename; if that is empty, bs->file->filename will be useless for path_combine() and an error should be emitted (containing bs->file->filename because desc_file_path (which is bs->file->exact_filename) is empty). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1417615043-26174-2-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-10block: Check create_opts before image creationMax Reitz
If a driver supports image creation, it needs to set the .create_opts field. We can use that to make sure .create_opts for both drivers involved is not NULL in bdrv_img_create(), which is important so that the create_opts pointer in that function is not NULL after the qemu_opts_append() calls and when going into qemu_opts_create(). Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10block: Omit bdrv_find_format for essential driversMax Reitz
We can always assume raw, file and qcow2 being available; so do not use bdrv_find_format() to locate their BlockDriver objects but statically reference the respective objects. Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10block: Don't probe for unknown backing file formatKevin Wolf
If a qcow2 image specifies a backing file format that doesn't correspond to any format driver that qemu knows, we shouldn't fall back to probing, but simply error out. Not looking up the backing file driver in bdrv_open_backing_file(), but just filling in the "driver" option if it isn't there moves us closer to the goal of having everything in QDict options and gets us the error handling of bdrv_open(), which correctly refuses unknown drivers. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1416935562-7760-4-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10raw: Prohibit dangerous writes for probed imagesKevin Wolf
If the user neglects to specify the image format, QEMU probes the image to guess it automatically, for convenience. Relying on format probing is insecure for raw images (CVE-2008-2004). If the guest writes a suitable header to the device, the next probe will recognize a format chosen by the guest. A malicious guest can abuse this to gain access to host files, e.g. by crafting a QCOW2 header with backing file /etc/shadow. Commit 1e72d3b (April 2008) provided -drive parameter format to let users disable probing. Commit f965509 (March 2009) extended QCOW2 to optionally store the backing file format, to let users disable backing file probing. QED has had a flag to suppress probing since the beginning (2010), set whenever a raw backing file is assigned. All of these additions that allow to avoid format probing have to be specified explicitly. The default still allows the attack. In order to fix this, commit 79368c8 (July 2010) put probed raw images in a restricted mode, in which they wouldn't be able to overwrite the first few bytes of the image so that they would identify as a different image. If a write to the first sector would write one of the signatures of another driver, qemu would instead zero out the first four bytes. This patch was later reverted in commit 8b33d9e (September 2010) because it didn't get the handling of unaligned qiov members right. Today's block layer that is based on coroutines and has qiov utility functions makes it much easier to get this functionality right, so this patch implements it. The other differences of this patch to the old one are that it doesn't silently write something different than the guest requested by zeroing out some bytes (it fails the request instead) and that it doesn't maintain a list of signatures in the raw driver (it calls the usual probe function instead). Note that this change doesn't introduce new breakage for false positive cases where the guest legitimately writes data into the first sector that matches the signatures of an image format (e.g. for nested virt): These cases were broken before, only the failure mode changes from corruption after the next restart (when the wrong format is probed) to failing the problematic write request. Also note that like in the original patch, the restrictions only apply if the image format has been guessed by probing. Explicitly specifying a format allows guests to write anything they like. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1416497234-29880-8-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10block: Read only one sector for format probingKevin Wolf
The only image format driver that even potentially accesses anything after 512 bytes in its bdrv_probe() implementation is VMDK, which reads a plain-text descriptor file. In practice, the field it's looking for seems to come first and will be well within the first 512 bytes, too. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1416497234-29880-7-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10block: Factor bdrv_probe_all() out of find_image_format()Markus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1416497234-29880-6-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10block: Add bdrv_get_node_nameFam Zheng
This returns the node name of a BDS. Remove the TODO comment and expect the callers to be explicit. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10block: Add bdrv_next_nodeFam Zheng
Similar to bdrv_next, this traverses through graph_bdrv_states. Will be useful to enumerate all the named nodes. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-11-14block: Fix max nb_sectors in bdrv_make_zeroFam Zheng
In bdrv_rw_co we report -EINVAL for nb_sectors > INT_MAX / BDRV_SECTOR_SIZE, so a caller shouldn't exceed it. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-id: 1415603264-21497-1-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-11Merge remote-tracking branch ↵Peter Maydell
'remotes/mjt/tags/pull-trivial-patches-2014-11-11' into staging trivial patches for 2014-11-11 # gpg: Signature made Tue 11 Nov 2014 14:38:39 GMT using RSA key ID A4C3D7DB # gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>" # gpg: aka "Michael Tokarev <mjt@corpit.ru>" # gpg: aka "Michael Tokarev <mjt@debian.org>" * remotes/mjt/tags/pull-trivial-patches-2014-11-11: block: Fix comment for bdrv_co_get_block_status sysbus: Correct SYSTEM_BUS(obj) defines target-i386: cpu: keeping function parameters alignment on new line xen-hvm: Remove redundant variable 'xstate' coroutine-sigaltstack: Change jmp_buf to sigjmp_buf pc-bios: petalogix-s3adsp1800.dtb: Use 'xlnx, xps-ethernetlite-2.00.a' instead of 'xlnx, xps-ethernetlite-2.00.b' gdbstub: Add a missing case of signal number translation in gdbstub numa: make 'info numa' take into account hotplugged memory slirp/smbd: modify/set several parameters in generated smbd.conf qemu-doc.texi: fix typos in x509 examples icc_bus: fix typo ICC_BRIGDE -> ICC_BRIDGE Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-11-11block: Fix comment for bdrv_co_get_block_statusFam Zheng
It returns more information than binary, fix the comment. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-11-06block: Propagate error in bdrv_img_create()Max Reitz
If the specified backing file could not be opened, do not generate a new error message which contains the message which has been generated by bdrv_open(), but just propagate the latter. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Peter Lieven <pl@kamp.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-11-03block: let mirror blockjob run in BDS AioContextStefan Hajnoczi
The mirror block job must run in the BlockDriverState AioContext so that it works with dataplane. Acquire the AioContext in blockdev.c so starting the block job is safe. Note that to_replace is treated separately from other BlockDriverStates in that it does not need to be in the same AioContext. Explicitly acquire/release to_replace's AioContext when accessing it. The completion code in block/mirror.c must perform BDS graph manipulation and bdrv_reopen() from the main loop. Use block_job_defer_to_main_loop() to achieve that. The bdrv_drain_all() call is not allowed outside the main loop since it could lead to lock ordering problems. Use bdrv_drain(bs) instead because we have acquired the AioContext so nothing else can sneak in I/O. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1413889440-32577-10-git-send-email-stefanha@redhat.com
2014-11-03block: add bdrv_drain()Stefan Hajnoczi
Now that op blockers are in use, we can ensure that no other sources are generating I/O on a BlockDriverState. Therefore it is possible to drain requests for a single BDS. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 1413889440-32577-7-git-send-email-stefanha@redhat.com
2014-11-03block: Add status callback to bdrv_amend_options()Max Reitz
Depending on the changed options and the image format, bdrv_amend_options() may take a significant amount of time. In these cases, a way to be informed about the operation's status is desirable. Since the operation is rather complex and may fundamentally change the image, implementing it as AIO or a coroutine does not seem feasible. On the other hand, implementing it as a block job would be significantly more difficult than a simple callback and would not add benefits other than progress report to the amending operation, because it should not actually be run as a block job at all. A callback may not be very pretty, but it's very easy to implement and perfectly fits its purpose here. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1414404776-4919-2-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03block.c: Fix type of IoOperationType variable in send_qmp_error_event()Peter Maydell
The local variable 'ac' in send_qmp_error_event() is declared with the wrong type, which causes clang to complain when it is initialized and again when it is used: block.c:3655:20: warning: implicit conversion from enumeration type 'enum IoOperationType' to different enumeration type 'BlockErrorAction' (aka 'enum BlockErrorAction') [-Wenum-conversion] ac = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE; ~ ^~~~~~~~~~~~~~~~~~~~~~ block.c:3655:45: warning: implicit conversion from enumeration type 'enum IoOperationType' to different enumeration type 'BlockErrorAction' (aka 'enum BlockErrorAction') [-Wenum-conversion] ac = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE; ~ ^~~~~~~~~~~~~~~~~~~~~~~ block.c:3656:62: warning: implicit conversion from enumeration type 'BlockErrorAction' (aka 'enum BlockErrorAction') to different enumeration type 'IoOperationType' (aka 'enum IoOperationType') [-Wenum-conversion] qapi_event_send_block_io_error(bdrv_get_device_name(bs), ac, action, ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^~ Correct the type to IoOperationType, and rename the variable to 'optype' to match its correct type. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com> Message-id: 1412969583-21045-1-git-send-email-peter.maydell@linaro.org Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03block: avoid creating oversized writes in multiwrite_mergePeter Lieven
Signed-off-by: Peter Lieven <pl@kamp.de> Reviewed-by: Ronnie Sahlberg <ronniesahlberg@gmail.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03BlockLimits: introduce max_transfer_lengthPeter Lieven
Signed-off-by: Peter Lieven <pl@kamp.de> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-10-23block: Respect underlying file's EOFMax Reitz
When falling through to the underlying file in bdrv_co_get_block_status(), if it returns that the query offset is beyond the file end (by setting *pnum to 0), return the range to be zero and do not let the number of sectors for which information could be obtained be overwritten. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23block: Add qemu_{,try_}blockalign0()Max Reitz
These functions call their non-0-counterparts and then fill the allocated buffer with 0 (if the allocation has been successful). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Lift device model API into BlockBackendMarkus Armbruster
Move device model attachment / detachment and the BlockDevOps device model callbacks and their wrappers from BlockDriverState to BlockBackend. Wrapper calls in block.c change from bdrv_dev_FOO_cb(bs, ...) to if (bs->blk) { bdrv_dev_FOO_cb(bs->blk, ...); } No change, because both bdrv_dev_change_media_cb() and bdrv_dev_resize_cb() do nothing when no device model is attached, and a device model can be attached only when bs->blk. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Rename BlockDriverCompletionFunc to BlockCompletionFuncMarkus Armbruster
I'll use it with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Rename BlockDriverAIOCB* to BlockAIOCB*Markus Armbruster
I'll use BlockDriverAIOCB with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Merge BlockBackend and BlockDriverState name spacesMarkus Armbruster
BlockBackend's name space is separate only to keep the initial patches simple. Time to merge the two. Retain bdrv_find() and bdrv_get_device_name() for now, to keep this series manageable. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Eliminate BlockDriverState member device_name[]Markus Armbruster
device_name[] can become non-empty only in bdrv_new_root() and bdrv_move_feature_fields(). The latter is used only to undo damage done by bdrv_swap(). The former is called only by blk_new_with_bs(). Therefore, when a BlockDriverState's device_name[] is non-empty, then it's been created with a BlockBackend, and vice versa. Furthermore, blk_new_with_bs() keeps the two names equal. Therefore, device_name[] is redundant. Eliminate it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Eliminate bdrv_iterate(), use bdrv_next()Markus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Connect BlockBackend and DriveInfoMarkus Armbruster
Make the BlockBackend own the DriveInfo. Change blockdev_init() to return the BlockBackend instead of the DriveInfo. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Connect BlockBackend to BlockDriverStateMarkus Armbruster
Convenience function blk_new_with_bs() creates a BlockBackend with its BlockDriverState. Callers have to unref both. The commit after next will relieve them of the need to unref the BlockDriverState. Complication: due to the silly way drive_del works, we need a way to hide a BlockBackend, just like bdrv_make_anon(). To emphasize its "special" status, give the function a suitably off-putting name: blk_hide_on_behalf_of_do_drive_del(). Unfortunately, hiding turns the BlockBackend's name into the empty string. Can't avoid that without breaking the blk->bs->device_name equals blk->name invariant. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Split bdrv_new_root() off bdrv_new()Markus Armbruster
Creating an anonymous BDS can't fail. Make that obvious. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-14block/migration: Disable cache invalidate for incoming migrationAlexey Kardashevskiy
When migrated using libvirt with "--copy-storage-all", at the end of migration there is race between NBD mirroring task trying to do flush and migration completion, both end up invalidating cache. Since qcow2 driver does not handle this situation very well, random crashes happen. This disables the BDRV_O_INCOMING flag for the block device being migrated once the cache has been invalidated. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> -- fixed parens by hand Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-10-03util: Emancipate id_wellformed() from QemuOptsMarkus Armbruster
IDs have long spread beyond QemuOpts: not everything with an ID necessarily goes through QemuOpts. Commit 9aebf3b is about such a case: block layer names are meant to be well-formed IDs, but some of them don't go through QemuOpts, and thus weren't checked. The commit fixed that the straightforward way: rename the internal QemuOpts helper id_wellformed() to qemu_opts_id_wellformed() and give it external linkage. Instead of using it directly in block.c, the commit adds wrapper bdrv_is_valid_name(), probably to hide the connection to QemuOpts. Go one logical step further: emancipate IDs from QemuOpts. Rename the function back to id_wellformed(), and put it in another file. While there, clean up its value to bool. Peel off the bdrv_is_valid_name() wrapper. [Replaced stray return 0 with return false to match bool returns used elsewhere in id_wellformed(). --Stefan] Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-25block: Validate node-nameKevin Wolf
The device_name of a BlockDriverState is currently checked because it is always used as a QemuOpts ID and qemu_opts_create() checks whether such IDs are wellformed. node-name is supposed to share the same namespace, but it isn't checked currently. This patch adds explicit checks both for device_name and node-name so that the same rules will still apply even if QemuOpts won't be used any more at some point. qemu-img used to use names with spaces in them, which isn't allowed any more. Replace them with underscores. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-25block: Improve message for device name clashing with node nameMarkus Armbruster
Suggested-by: Benoit Canet <benoit.canet@nodalink.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-25block: Keep DriveInfo alive until BlockDriverState diesMarkus Armbruster
If the BDS's refcnt > 0, drive_del() destroys the DriveInfo, but not the BDS. This can happen in three places: * Device model destruction during unplug: blockdev_auto_del() * Xen IDE unplug: pci_piix3_xen_ide_unplug() * drive_del command when no device model is attached: do_drive_del() The other callers of drive_del are on error paths where refcnt == 1. If the user somehow manages to plug in a device model using a BDS that has gone through drive_del(), the legacy configuration passed in DriveInfo doesn't reach the device model, and automatic deletion on unplug doesn't work. Worse, some device models such as scsi-disk crash when DriveInfo doesn't exist. This is theoretical; I didn't research an actual reproducer. The problem was introduced when we replaced DriveInfo reference counting by BDS reference counting in commit a94a3fa..fa510eb. Fix by keeping DriveInfo alive until its BDS dies. This affects qemu_drive_opts: now you can't reuse the same ID for new drive options until the BDS dies. Before, you could, but since the code always attempts to create a BDS with the same ID next, the enclosing operation "create a new drive" failed anyway. Different error path, same result. Unfortunately, the fix involves use of blockdev.c stuff from block.c, which is a layering violation. Fortunately, my forthcoming BlockBackend work will get rid of it again. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-22block: Rename qemu_aio_release -> qemu_aio_unrefFam Zheng
Suggested-by: Benoît Canet <benoit.canet@irqsave.net> Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Drop AIOCBInfo.cancelFam Zheng
Now that all the implementations are converted to asynchronous version and we can emulate synchronous cancellation with it. Let's drop the unused member. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Drop bdrv_em_aiocb_info.cancelFam Zheng
Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Drop bdrv_em_co_aiocb_info.cancelFam Zheng
Also drop the now unused ->done pointer. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Add bdrv_aio_cancel_asyncFam Zheng
This is the async version of bdrv_aio_cancel, which doesn't block the caller. It guarantees that the cb is called either before returning or some time later. bdrv_aio_cancel can base on bdrv_aio_cancel_async, later we can convert all .io_cancel implementations to .io_cancel_async, and the aio_poll is the common logic. In the end, .io_cancel can be dropped. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Add refcnt in BlockDriverAIOCBFam Zheng
This will be useful in synchronous cancel emulation with bdrv_aio_cancel_async. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-11block: extend BLOCK_IO_ERROR with reason stringLuiz Capitulino
BLOCK_IO_ERROR events are logged by libvirt, which helps with post mortem analysis of guests. However, one information that we miss today is a human readable string describing the cause of the I/O error. This commit adds that string it to BLOCK_IO_ERROR. Note that this string is a debugging aid for humans, meaning that it should not parsed by applications. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10block: Make the block accounting functions operate on BlockAcctStatsBenoît Canet
This is the next step for decoupling block accounting functions from BlockDriverState. In a future commit the BlockAcctStats structure will be moved from BlockDriverState to the device models structures. Note that bdrv_get_stats was introduced so device models can retrieve the BlockAcctStats structure of a BlockDriverState without being aware of it's layout. This function should go away when BlockAcctStats will be embedded in the device models structures. CC: Kevin Wolf <kwolf@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Keith Busch <keith.busch@intel.com> CC: Anthony Liguori <aliguori@amazon.com> CC: "Michael S. Tsirkin" <mst@redhat.com> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: Peter Maydell <peter.maydell@linaro.org> CC: Michael Tokarev <mjt@tls.msk.ru> CC: John Snow <jsnow@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Alexander Graf <agraf@suse.de> CC: Max Reitz <mreitz@redhat.com> Signed-off-by: Benoît Canet <benoit.canet@nodalink.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10block: Extract the block accounting codeBenoît Canet
The plan is to add new accounting metrics (latency, invalid requests, failed requests, queue depth) and block.c is overpopulated so it will be better to work in a separate module. Moreover the long term plan is to have statistics in each of the BDS of the graph for metrology purpose; this means that the device model statistics must move from the topmost BDS to the device model. So we need to decouple the statistic code from BlockDriverState. This is another argument for the extraction of the code in a separate module. CC: Kevin Wolf <kwolf@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Max Reitz <mreitz@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: Benoit Canet <benoit@irqsave.net> CC: Fam Zheng <famz@redhat.com> CC: Peter Crosthwaite <peter.crosthwaite@xilinx.com> CC: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Benoît Canet <benoit.canet@nodalink.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10block: Extract the BlockAcctStats structureBenoît Canet
Extract the block accounting statistics into a structure so the block device models can hold them in the future. CC: Kevin Wolf <kwolf@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Max Reitz <mreitz@redhat.com> CC: Eric Blake <eblake@redhat.com> Signed-off-by: Benoît Canet <benoit.canet@nodalink.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10block: extend BLOCK_IO_ERROR event with nospace indicatorLuiz Capitulino
Management software, such as RHEV's vdsm, want to be able to allocate disk space on demand. The basic use case is to start a VM with a small disk and then the disk is enlarged when QEMU hits a ENOSPC condition. To this end, the management software has to be notified when QEMU encounters ENOSPC. The solution implemented by this commit is simple: it extends the BLOCK_IO_ERROR with a 'nospace' key, which is true when QEMU is stopped due to ENOSPC. Note that support for querying this event is already present in query-block by means of the 'io-status' key. Also, the new 'nospace' BLOCK_IO_ERROR field shares the same semantics with 'io-status', which basically means that werror= has to be set to either 'stop' or 'enospc' to enable 'nospace'. Finally, this commit also updates the 'io-status' key doc in the schema with a list of supported device models. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-08block: kill tail whitespace in block.cLiu Yuan
Cc: Kevin Wolf <kwolf@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Liu Yuan <namei.unix@gmail.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-29block: fix overlapping multiwrite requestsStefan Hajnoczi
When request A is a strict superset of request B: AAAAAAAA BBBB multiwrite_merge() merges them as follows: AABBBB The tail of request A should have been included: AABBBBAA This patch fixes data loss but this code path is probably rare. Since guests cannot assume ordering between in-flight requests, few applications submit overlapping write requests. Reported-by: Slava Pestov <sviatoslav.pestov@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-08-29block: Add AIO context notifiersMax Reitz
If a long-running operation on a BDS wants to always remain in the same AIO context, it somehow needs to keep track of the BDS changing its context. This adds a function for registering callbacks on a BDS which are called whenever the BDS is attached or detached from an AIO context. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>