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2016-02-02qed: Assign bs->file->bs to file in bdrv_qed_co_get_block_statusFam Zheng
Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1453780743-16806-8-git-send-email-famz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02block: Add "file" output parameter to block status query functionsFam Zheng
The added parameter can be used to return the BDS pointer which the valid offset is referring to. Its value should be ignored unless BDRV_BLOCK_OFFSET_VALID in ret is set. Until block drivers fill in the right value, let's clear it explicitly right before calling .bdrv_get_block_status. The "bs->file" condition in bdrv_co_get_block_status is kept now to keep iotest case 102 passing, and will be fixed once all drivers return the right file pointer. Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1453780743-16806-2-git-send-email-famz@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-01-20block: Rename BDRV_O_INCOMING to BDRV_O_INACTIVEKevin Wolf
Instead of covering only the state of images on the migration destination before the migration is completed, the flag will also cover the state of images on the migration source after completion. This common state implies that the image is technically still open, but no writes will happen and any cached contents will be reloaded from disk if and when the image leaves this state. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20block: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-13error: Use error_prepend() where it makes obvious senseMarkus Armbruster
Done with this Coccinelle semantic patch @@ expression FMT, E1, E2; expression list ARGS; @@ - error_setg(E1, FMT, ARGS, error_get_pretty(E2)); + error_propagate(E1, E2);/*###*/ + error_prepend(E1, FMT/*@@@*/, ARGS); followed by manual cleanup, first because I can't figure out how to make Coccinelle transform strings, and second to get rid of now superfluous error_propagate(). We now use or propagate the original error whole instead of just its message obtained with error_get_pretty(). This avoids suppressing its hint (see commit 50b7b00), but I can't see how the errors touched in this commit could come with hints. It also improves the message printed with &error_abort when we screw up (see commit 1e9b65b). Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2015-11-12qed: Implement .bdrv_drainFam Zheng
The "need_check_timer" is used to clear the "NEED_CHECK" flag in the image header after a grace period once metadata update has finished. In compliance to the bdrv_drain semantics we should make sure it remains deleted once .bdrv_drain is called. We cannot reuse qed_need_check_timer_cb because here it doesn't satisfy the assertion. Do the "plug" and "flush" calls manually. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1447064214-29930-10-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-10-16block: Remove bdrv_swap()Kevin Wolf
bdrv_swap() is unused now. Remove it and all functions that have no other users than bdrv_swap(). In particular, this removes the .bdrv_rebind callbacks from block drivers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16block: Convert bs->backing_hd to BdrvChildKevin Wolf
This is the final step in converting all of the BlockDriverState pointers that block drivers use to BdrvChild. After this patch, bs->children contains the full list of child nodes that are referenced by a given BDS, and these children are only referenced through BdrvChild, so that updating the pointer in there is enough for changing edges in the graph. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16block: Convert bs->file to BdrvChildKevin Wolf
This patch removes the temporary duplication between bs->file and bs->file_child by converting everything to BdrvChild. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-09-14block: Drop drv parameter from bdrv_open()Max Reitz
Now that this parameter is effectively unused, we can drop it and just pass NULL on to bdrv_open_inherit(). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-06-22qerror: Clean up QERR_ macros to expand into a single stringMarkus Armbruster
These macros expand into error class enumeration constant, comma, string. Unclean. Has been that way since commit 13f59ae. The error class is always ERROR_CLASS_GENERIC_ERROR since the previous commit. Clean up as follows: * Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and delete it from the QERR_ macro. No change after preprocessing. * Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into error_setg(...). Again, no change after preprocessing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-04-28block: use bdrv_get_device_or_node_name() in error messagesAlberto Garcia
There are several error messages that identify a BlockDriverState by its device name. However those errors can be produced in nodes that don't have a device name associated. In those cases we should use bdrv_get_device_or_node_name() to fall back to the node name and produce a more meaningful message. The messages are also updated to use the more generic term 'node' instead of 'device'. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 9823a1f0514fdb0692e92868661c38a9e00a12d6.1428485266.git.berto@igalia.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28Convert (ffs(val) - 1) to ctz32(val)Stefan Hajnoczi
This commit was generated mechanically by coccinelle from the following semantic patch: @@ expression val; @@ - (ffs(val) - 1) + ctz32(val) The call sites have been audited to ensure the ffs(0) - 1 == -1 case never occurs (due to input validation, asserts, etc). Therefore we don't need to worry about the fact that ctz32(0) == 32. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1427124571-28598-5-git-send-email-stefanha@redhat.com Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06qed: check for header size overflowStefan Hajnoczi
Header size is denoted in clusters. The maximum cluster size is 64 MB but there is no limit on header size. Check for uint32_t overflow in case the header size field has a whacky value. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1421065893-18875-2-git-send-email-stefanha@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: 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>
2014-09-22block: 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>
2014-09-22qed: Drop qed_aiocb_info.cancelFam Zheng
Also drop the now unused ->finished field. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-12block: round up file size to nearest sectorHu Tao
Currently the file size requested by user is rounded down to nearest sector, causing the actual file size could be a bit less than the size user requested. Since some formats (like qcow2) record virtual disk size in bytes, this can make the last few bytes cannot be accessed. This patch fixes it by rounding up file size to nearest sector so that the actual file size is no less than the requested file size. Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-15qed: Handle failure for potentially large allocationsKevin Wolf
Some code in the block layer makes potentially huge allocations. Failure is not completely unexpected there, so avoid aborting qemu and handle out-of-memory situations gracefully. This patch addresses the allocations in the qed block driver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-07-18block: Add Error argument to bdrv_refresh_limits()Kevin Wolf
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-14qed: Make qiov match request size until backing file EOFKevin Wolf
If a QED image has a shorter backing file and a read request to unallocated clusters goes across EOF of the backing file, the backing file sees a shortened request and the rest is filled with zeros. However, the original too long qiov was used with the shortened request. This patch makes the qiov size match the request size, avoiding a potential buffer overflow in raw-posix. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-07-01qemu-img create: add 'nocow' optionChunyan Liu
Add 'nocow' option so that users could have a chance to set NOCOW flag to newly created files. It's useful on btrfs file system to enhance performance. Btrfs has low performance when hosting VM images, even more when the guest in those VM are also using btrfs as file system. One way to mitigate this bad performance is to turn off COW attributes on VM files. Generally, there are two ways to turn off NOCOW on btrfs: a) by mounting fs with nodatacow, then all newly created files will be NOCOW. b) per file. Add the NOCOW file attribute. It could only be done to empty or new files. This patch tries the second way, according to the option, it could add NOCOW per file. For most block drivers, since the create file step is in raw-posix.c, so we can do setting NOCOW flag ioctl in raw-posix.c only. But there are some exceptions, like block/vpc.c and block/vdi.c, they are creating file by calling qemu_open directly. For them, do the same setting NOCOW flag ioctl work in them separately. [Fixed up 082.out due to the new 'nocow' creation option --Stefan] Signed-off-by: Chunyan Liu <cyliu@suse.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-26block: Catch backing files assigned to non-COW driversKevin Wolf
Since we parse backing.* options to add a backing file from the command line when the driver didn't assign one, it has been possible to have a backing file for e.g. raw images (it just was never accessed). This is obvious nonsense and should be rejected. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-06-16cleanup QEMUOptionParameterChunyan Liu
Now that all backend drivers are using QemuOpts, remove all QEMUOptionParameter related codes. Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com> Signed-off-by: Chunyan Liu <cyliu@suse.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16qed.c: replace QEMUOptionParameter with QemuOptsChunyan Liu
One extra change is to define QED_DEFAULT_CLUSTER_SIZE = 65536 instead of 64 * 1024; because: according to existing create_options, "cluster size" has default value = QED_DEFAULT_CLUSTER_SIZE, after switching to create_opts, this has to be stringized and set to .def_value_str. That is, .def_value_str = stringify(QED_DEFAULT_CLUSTER_SIZE), so the QED_DEFAULT_CLUSTER_SIZE could not be a expression. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com> Signed-off-by: Chunyan Liu <cyliu@suse.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16change block layer to support both QemuOpts and QEMUOptionParamterChunyan Liu
Change block layer to support both QemuOpts and QEMUOptionParameter. After this patch, it will change backend drivers one by one. At the end, QEMUOptionParameter will be removed and only QemuOpts is kept. Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com> Signed-off-by: Chunyan Liu <cyliu@suse.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-04qed: use BlockDriverState's AioContextStefan Hajnoczi
Drop the assumption that we're using the main AioContext. Convert qemu_bh_new() to aio_bh_new() and qemu_aio_wait() to aio_poll() so we're using the BlockDriverState's AioContext. Implement .bdrv_detach/attach_aio_context() interfaces to move the QED_F_NEED_CHECK timer from the old AioContext to the new one. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-22convert fprintf() calls to error_setg() in block/qed.c:bdrv_qed_create()Aakriti Gupta
This patch converts fprintf() calls to error_setg() in block/qed.c:bdrv_qed_create() (error_setg() is part of error reporting API in include/qapi/error.h) Signed-off-by: Aakriti Gupta <aakritty@gmail.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-03-19block: Add error handling to bdrv_invalidate_cache()Kevin Wolf
If it returns an error, the migrated VM will not be started, but qemu exits with an error message. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-03-13block: Update image size in bdrv_invalidate_cache()Kevin Wolf
After migration has completed, we call bdrv_invalidate_cache() so that drivers which cache some data drop their stale copy of the data and reread it from the image file to get a new version of data that the source modified while the migration was running. Reloading metadata from the image file is useless, though, if the size of the image file stays stale (this is a value that is cached for all image formats in block.c). Reads from (meta)data after the old EOF return only zeroes, causing image corruption. We need to update bs->total_sectors in all layers that could potentially have changed their size (i.e. backing files are not a concern - if they are changed, we're in bigger trouble) Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-02-21block: do not abuse EMEDIUMTYPEPaolo Bonzini
Returning "Wrong medium type" for an image that does not have a valid header is a bit weird. Improve the error by mentioning what format was trying to open it. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21qed: correctly propagate errorsPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21block: Make bdrv_file_open() staticMax Reitz
Add the bdrv_open() option BDRV_O_PROTOCOL which results in passing the call to bdrv_file_open(). Additionally, make bdrv_file_open() static and therefore bdrv_open() the only way to call it. Consequently, all existing calls to bdrv_file_open() have to be adjusted to use bdrv_open() with the BDRV_O_PROTOCOL flag instead. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-31block: remove QED .bdrv_make_empty implementationJeff Cody
The QED .bdrv_make_empty() implementation does nothing but return -ENOTSUP, which causes problems in bdrv_commit(). Since the function stub exists for QED, it is called, which then always returns an error. The proper way to not support an optional driver function stub is to just not implement it, so let's remove the stub. Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-01-24block: Move initialisation of BlockLimits to bdrv_refresh_limits()Kevin Wolf
This function separates filling the BlockLimits from bdrv_open(), which allows it to call it from other operations which may change the limits (e.g. modifications to the backing file chain or bdrv_reopen) Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-22block: Allow reference for bdrv_file_open()Max Reitz
Allow specifying a reference to an existing block device (by name) for bdrv_file_open() instead of a filename and/or options. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-12-03block drivers: expose requirement for write same alignment from formatsPaolo Bonzini
This will let misaligned but large requests use zero clusters. This is important because the cluster size is not guest visible. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-03block drivers: add discard/write_zeroes properties to bdrv_get_info ↵Paolo Bonzini
implementation Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28block: add flags to bdrv_*_write_zeroesPeter Lieven
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-12block: Error parameter for create functionsMax Reitz
Add an Error ** parameter to bdrv_create and its associated functions to allow more specific error messages. Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12block: Error parameter for open functionsMax Reitz
Add an Error ** parameter to bdrv_open, bdrv_file_open and associated functions to allow more specific error messages. Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12bdrv: Use "Error" for creating imagesMax Reitz
Add an Error ** parameter to BlockDriver.bdrv_create to allow more specific error messages. Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12bdrv: Use "Error" for opening imagesMax Reitz
Add an Error ** parameter to BlockDriver.bdrv_open and BlockDriver.bdrv_file_open to allow more specific error messages. Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-06block: return get_block_status data and flags for formatsPaolo Bonzini
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06block: introduce bdrv_get_block_status APIPaolo Bonzini
For now, bdrv_get_block_status is just another name for bdrv_is_allocated. The next patches will add more flags. This also touches all block drivers with a mostly mechanical rename. The sole exception is cow; because it calls cow_co_is_allocated from the read code, we keep that function and make cow_co_get_block_status a wrapper. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06block: make bdrv_delete() staticFam Zheng
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no longer public and should be called by bdrv_unref() if refcnt is decreased to 0. This is an identical change because effectively, there's no multiple reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22aio / timers: Switch entire codebase to the new timer APIAlex Bligh
This is an autogenerated patch using scripts/switch-timer-api. Switch the entire code base to using the new timer API. Note this patch may introduce some line length issues. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-06-28block: change default of .has_zero_init to 0Peter Lieven
.has_zero_init defaults to 1 for all formats and protocols. this is a dangerous default since this means that all new added drivers need to manually overwrite it to 0 if they do not ensure that a device is zero initialized after bdrv_create(). if a driver needs to explicitly set this value to 1 its easier to verify the correctness in the review process. during review of the existing drivers it turned out that ssh and gluster had a wrong default of 1. both protocols support host_devices as backend which are not by default zero initialized. this wrong assumption will lead to possible corruption if qemu-img convert is used to write to such a backend. vpc and vmdk also defaulted to 1 altough they support fixed respectively flat extends. this has to be addresses in separate patches. both formats as well as the mentioned ssh and gluster are turned to the default of 0 with this patch for safety. a similar problem with the wrong default existed for iscsi most likely because the driver developer did oversee the default value of 1. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>