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2016-09-05block: Convert bdrv_pwrite_compressed() to BdrvChildPavel Butsykin1-1/+1
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Eric Blake <eblake@redhat.com> CC: Jeff Cody <jcody@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: John Snow <jsnow@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-05block: switch blk_write_compressed() to byte-based interfacePavel Butsykin1-19/+4
This is a preparatory patch, which continues the general trend of the transition to the byte-based interfaces. bdrv_check_request() and blk_check_request() are no longer used, thus we can remove them. Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Jeff Cody <jcody@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: John Snow <jsnow@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-05block: Accept node-name for block-streamKevin Wolf1-0/+16
In order to remove the necessity to use BlockBackend names in the external API, we want to allow node-names everywhere. This converts block-stream to accept a node-name without lifting the restriction that we're operating at a root node. In case of an invalid device name, the command returns the GenericError error class now instead of DeviceNotFound, because this is what qmp_get_root_bs() returns. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com>
2016-07-20block: Convert BB interface to byte-based discardsEric Blake1-14/+11
Change sector-based blk_discard(), blk_co_discard(), and blk_aio_discard() to instead be byte-based blk_pdiscard(), blk_co_pdiscard(), and blk_aio_pdiscard(). NBD gets a lot simpler now that ignoring the unaligned portion of a byte-based discard request is handled under the hood by the block layer. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-6-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20block: Convert bdrv_aio_discard() to byte-basedEric Blake1-1/+2
Another step towards byte-based interfaces everywhere. Replace the sector-based bdrv_aio_discard() with a new byte-based bdrv_aio_pdiscard(), which silently ignores any unaligned head or tail. Driver callbacks will be converted in followup patches. Signed-off-by: Eric Blake <eblake@redhat.com> Message-id: 1468624988-423-5-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20block: Convert bdrv_discard() to byte-basedEric Blake1-1/+2
Another step towards byte-based interfaces everywhere. Replace the sector-based bdrv_discard() with a new byte-based bdrv_pdiscard(), which silently ignores any unaligned head or tail. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-3-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20block: Convert bdrv_co_discard() to byte-basedEric Blake1-1/+2
Another step towards byte-based interfaces everywhere. Replace the sector-based bdrv_co_discard() with a new byte-based bdrv_co_pdiscard(), which silently ignores any unaligned head or tail. Driver callbacks will be converted in followup patches. By calculating the alignment outside of the loop, and clamping the max discard to an aligned value, we can simplify the actions done within the loop. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-2-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-13block/qdev: Allow configuring rerror/werror with qdev propertiesKevin Wolf1-0/+1
The rerror/werror policies are implemented in the devices, so that's where they should be configured. In comparison to the old options in -drive, the qdev properties are only added to those devices that actually support them. If the option isn't given (or "auto" is specified), the setting of the BlockBackend is used for compatibility with the old options. For block jobs, "auto" is the same as "enospc". Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-07-13coroutine: move entry argument to qemu_coroutine_createPaolo Bonzini1-4/+4
In practice the entry argument is always known at creation time, and it is confusing that sometimes qemu_coroutine_enter is used with a non-NULL argument to re-enter a coroutine (this happens in block/sheepdog.c and tests/test-coroutine.c). So pass the opaque value at creation time, for consistency with e.g. aio_bh_new. Mostly done with the following semantic patch: @ entry1 @ expression entry, arg, co; @@ - co = qemu_coroutine_create(entry); + co = qemu_coroutine_create(entry, arg); ... - qemu_coroutine_enter(co, arg); + qemu_coroutine_enter(co); @ entry2 @ expression entry, arg; identifier co; @@ - Coroutine *co = qemu_coroutine_create(entry); + Coroutine *co = qemu_coroutine_create(entry, arg); ... - qemu_coroutine_enter(co, arg); + qemu_coroutine_enter(co); @ entry3 @ expression entry, arg; @@ - qemu_coroutine_enter(qemu_coroutine_create(entry), arg); + qemu_coroutine_enter(qemu_coroutine_create(entry, arg)); @ reentry @ expression co; @@ - qemu_coroutine_enter(co, NULL); + qemu_coroutine_enter(co); except for the aforementioned few places where the semantic patch stumbled (as expected) and for test_co_queue, which would otherwise produce an uninitialized variable warning. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Convert bdrv_co_preadv/pwritev to BdrvChildKevin Wolf1-2/+2
This is the final patch for converting the common I/O path to take a BdrvChild parameter instead of BlockDriverState. The completion of this conversion means that all users that perform I/O on an image need to actually hold a reference (in the form of BdrvChild, possible as part of a BlockBackend) to that image. This also protects against inconsistent use of BlockBackend vs. BlockDriverState functions because direct use of a BlockDriverState isn't possible any more and blk->root is private for block-backends.c. In addition, we can now distinguish different users in the I/O path, and the future op blockers work is going to add assertions based on permissions stored in BdrvChild. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Convert bdrv_pwrite_zeroes() to BdrvChildKevin Wolf1-0/+5
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Switch transfer length bounds to byte-basedEric Blake1-5/+5
Sector-based limits are awkward to think about; in our on-going quest to move to byte-based interfaces, convert max_transfer_length and opt_transfer_length. Rename them (dropping the _length suffix) so that the compiler will help us catch the change in semantics across any rebased code, and improve the documentation. Use unsigned values, so that we don't have to worry about negative values and so that bit-twiddling is easier; however, we are still constrained by 2^31 of signed int in most APIs. When a value comes from an external source (iscsi and raw-posix), sanitize the results to ensure that opt_transfer is a power of 2. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Give nonzero result to blk_get_max_transfer_length()Eric Blake1-3/+4
Making all callers special-case 0 as unlimited is awkward, and we DO have a hard maximum of BDRV_REQUEST_MAX_SECTORS given our current block layer API limits. In the case of scsi, this means that we now always advertise a limit to the guest, even in cases where the underlying layers previously use 0 for no inherent limit beyond the block layer. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-25block: Make blk_co_preadv/pwritev() publicKevin Wolf1-7/+14
Also add trace points now that the function can be directly called. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com>
2016-05-25block: Default to enabled write cache in blk_new()Kevin Wolf1-1/+2
The existing users of the function are: 1. blk_new_open(), which already enabled the write cache 2. Some test cases that don't care about the setting 3. blockdev_init() for empty drives, where the cache mode is overridden with the value from the options when a medium is inserted Therefore, this patch doesn't change the current behaviour. It will be convenient, however, for additional users of blk_new() (like block jobs) if the most sensible WCE setting is the default. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com>
2016-05-25block: Rename blk_write_zeroes()Eric Blake1-7/+7
Commit 983a1600 changed the semantics of blk_write_zeroes() to be byte-based rather than sector-based, but did not change the name, which is an open invitation for other code to misuse the function. Renaming to pwrite_zeroes() makes it more in line with other byte-based interfaces, and will help make it easier to track which remaining write_zeroes interfaces still need conversion. Reported-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25block: Fix reconfiguring graph with drained nodesKevin Wolf1-4/+5
When changing the BlockDriverState that a BdrvChild points to while the node is currently drained, we must call the .drained_end() parent callback. Conversely, when this means attaching a new node that is already drained, we need to call .drained_begin(). bdrv_root_attach_child() takes now an opaque parameter, which is needed because the callbacks must also be called if we're attaching a new child to the BlockBackend when the root node is already drained, and they need a way to identify the BlockBackend. Previously, child->opaque was set too late and the callbacks would still see it as NULL. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-25block: Drop errp parameter from blk_new()Max Reitz1-7/+2
blk_new() cannot fail so its Error ** parameter has become superfluous. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-25block: Make bdrv_open() return a BDSMax Reitz1-4/+2
There are no callers to bdrv_open() or bdrv_open_inherit() left that pass a pointer to a non-NULL BDS pointer as the first argument of these functions, so we can finally drop that parameter and just make them return the new BDS. Generally, the following pattern is applied: bs = NULL; ret = bdrv_open(&bs, ..., &local_err); if (ret < 0) { error_propagate(errp, local_err); ... } by bs = bdrv_open(..., errp); if (!bs) { ret = -EINVAL; ... } Of course, there are only a few instances where the pattern is really pure. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-25block: Drop blk_new_with_bs()Max Reitz1-23/+7
Its only caller is blk_new_open(), so we can just inline it there. The bdrv_new_root() call is dropped in the process because we can just let bdrv_open() create the BDS. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-25block: Fix bdrv_next() memory leakKevin Wolf1-23/+18
The bdrv_next() users all leaked the BdrvNextIterator after completing the iteration. Simply changing bdrv_next() to free the iterator before returning NULL at the end of list doesn't work because some callers exit the loop before looking at all BDSes. This patch moves the BdrvNextIterator from the heap to the stack of the caller and switches to a bdrv_first()/bdrv_next() interface for initialising the iterator. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-19block: Remove BlockDriverState.blkKevin Wolf1-8/+0
This patch removes the remaining users of bs->blk, which will allow us to have multiple BBs on top of a single BDS. In the meantime, all checks that are currently in place to prevent the user from creating such setups can be switched to bdrv_has_blk() instead of accessing BDS.blk. Future patches can allow them and e.g. enable users to mirror to a block device that already has a BlockBackend on it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19block: Avoid bs->blk in bdrv_next()Kevin Wolf1-22/+50
We need to introduce a separate BdrvNextIterator struct that can keep more state than just the current BDS in order to avoid using the bs->blk pointer. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19block: Add bdrv_has_blk()Kevin Wolf1-0/+17
In many cases we just want to know whether a BDS has at least one BB attached, without needing to know the exact BB that is attached. In contrast to bs->blk, this is still a valid question when more than one BB can be attached, so just answer it by checking the parents list. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19block: Remove bdrv_aio_multiwrite()Kevin Wolf1-14/+0
Since virtio-blk implements request merging itself these days, the only remaining users are test cases for the function. That doesn't make the function exactly useful any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-05-19block: User BdrvChild callback for device nameKevin Wolf1-0/+6
In order to get rid of bs->blk for bdrv_get_device_name() and bdrv_get_device_or_node_name(), ask all parents for their name and simply pick the first one. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19block: Use BdrvChild callbacks for change_media/resizeKevin Wolf1-1/+14
We want to get rid of BlockDriverState.blk in order to allow multiple BlockBackends per BDS. Converting the device callbacks in block.c (which assume a single BlockBackend) to per-child callbacks gets us rid of the first few instances. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19block: Decouple throttling from BlockDriverStateKevin Wolf1-23/+14
This moves the throttling related part of the BDS life cycle management to BlockBackend. The throttling group reference is now kept even when no medium is inserted. With this commit, throttling isn't disabled and then re-enabled any more during graph reconfiguration. This fixes the temporary breakage of I/O throttling when used with live snapshots or block jobs that manipulate the graph. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Drain throttling queue with BdrvChild callbackKevin Wolf1-5/+27
This removes the last part of I/O throttling from block/io.c and moves it to the BlockBackend. Instead of having knowledge about throttling inside io.c, we can call a BdrvChild callback .drained_begin/end, which happens to drain the throttled requests for BlockBackend parents. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Introduce BdrvChild.opaqueKevin Wolf1-0/+2
BlockBackends use it to get a back pointer from BdrvChild to BlockBackend in any BdrvChildRole callbacks. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Move I/O throttling configuration functions to BlockBackendKevin Wolf1-2/+41
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Move actual I/O throttling to BlockBackendKevin Wolf1-0/+10
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Move throttling fields from BDS to BBKevin Wolf1-5/+8
This patch changes where the throttling state is stored (used to be the BlockDriverState, now it is the BlockBackend), but it doesn't actually make it a BB level feature yet. For example, throttling is still disabled when the BDS is detached from the BB. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Convert throttle_group_get_name() to BlockBackendKevin Wolf1-1/+1
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Introduce BlockBackendPublicKevin Wolf1-0/+17
Some features, like I/O throttling, are implemented outside block-backend.c, but still want to keep information in BlockBackend, e.g. list entries that allow keeping a list of BlockBackends. In order to avoid exposing the whole struct layout in the public header file, this patch introduces an embedded public struct where such information can be added and a pair of functions to convert between BlockBackend and BlockBackendPublic. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Make sure throttled BDSes always have a BBKevin Wolf1-0/+3
It was already true in principle that a throttled BDS always has a BB attached, except that the order of operations while attaching or detaching a BDS to/from a BB wasn't careful enough. This commit breaks graph manipulations while I/O throttling is enabled. It would have been possible to keep things working with some temporary hacks, but quite cumbersome, so it's not worth the hassle. We'll fix things again in a minute. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-12block: Kill unused sector-based blk_* functionsEric Blake1-51/+0
Now that there are no remaining clients, we can drop the sector-based blk_read(), blk_write(), blk_aio_readv(), and blk_aio_writev(). Sadly, there are still remaining sector-based interfaces, such as blk_*discard(), or blk_write_compressed(); those will have to wait for another day. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Introduce byte-based aio read/writeEric Blake1-1/+17
blk_aio_readv() and blk_aio_writev() are annoying in that they can't access sub-sector granularity, and cannot pass flags. Also, they require the caller to pass redundant information about the size of the I/O (qiov->size in bytes must match nb_sectors in sectors). Add new blk_aio_preadv() and blk_aio_pwritev() functions to fix the flaws. The next few patches will upgrade callers, then finally delete the old interfaces. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Switch blk_*write_zeroes() to byte interfaceEric Blake1-22/+11
Sector-based blk_write() should die; convert the one-off variant blk_write_zeroes() to use an offset/count interface instead. Likewise for blk_co_write_zeroes() and blk_aio_write_zeroes(). Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Switch blk_read_unthrottled() to byte interfaceEric Blake1-4/+4
Sector-based blk_read() should die; convert the one-off variant blk_read_unthrottled(). Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Allow BDRV_REQ_FUA through blk_pwrite()Eric Blake1-2/+4
We have several block drivers that understand BDRV_REQ_FUA, and emulate it in the block layer for the rest by a full flush. But without a way to actually request BDRV_REQ_FUA during a pass-through blk_pwrite(), FUA-aware block drivers like NBD are forced to repeat the emulation logic of a full flush regardless of whether the backend they are writing to could do it more efficiently. This patch just wires up a flags argument; followup patches will actually make use of it in the NBD driver and in qemu-io. Signed-off-by: Eric Blake <eblake@redhat.com> Acked-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Rename bdrv_co_do_preadv/writev to bdrv_co_preadv/writevKevin Wolf1-2/+2
It used to be an internal helper function just for implementing bdrv_co_do_readv/writev(), but now that it's a public interface, it deserves a name without "do" in it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12block: introduce bdrv_no_throttling_begin/endPaolo Bonzini1-4/+2
Extract the handling of throttling from bdrv_flush_io_queue. These new functions will soon become BdrvChildRole callbacks, as they can be generalized to "beginning of drain" and "end of drain". Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15block: Don't ignore flags in blk_{,co,aio}_write_zeroes()Kevin Wolf1-3/+4
Commit 57d6a428 neglected to pass the given flags to blk_aio_prwv(), which broke discard by WRITE SAME for scsi-disk (the UNMAP bit would be ignored). Commit fc1453cd introduced the same bug for blk_write_zeroes(). This is used for 'qemu-img convert' without has_zero_init (e.g. on a block device) and for preallocation=falloc in parallels. Commit 8896e088 is the version for blk_co_write_zeroes(). This function is only used in qemu-io. Reported-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-04-15block: Fix blk_aio_write_zeroes()Kevin Wolf1-7/+13
Commit 57d6a428 broke blk_aio_write_zeroes() because in some write functions in the call path don't have an explicit length argument but reuse qiov->size instead. Which is great, except that write_zeroes doesn't have a qiov, which this commit interprets as 0 bytes. Consequently, blk_aio_write_zeroes() didn't effectively do anything. This patch introduces an explicit acb->bytes in BlkAioEmAIOCB and uses that instead of acb->rwco.size. The synchronous version of the function is okay because it does pass a qiov (with the right size and a NULL pointer as its base). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30block: Remove BDRV_O_CACHE_WBKevin Wolf1-11/+0
The previous patches have successively made blk->enable_write_cache the true source for the information whether a writethrough mode must be implemented. The corresponding BDRV_O_CACHE_WB is only useless baggage we're carrying around, so now's the time to remove it. At the same time, we remove the 'cache.writeback' option parsing on the BDS level as the only effect was setting the BDRV_O_CACHE_WB flag. This change requires test cases that explicitly enabled the option to drop it. Other than that and the change of the error message when writethrough is enabled on the BDS level (from "Can't set writethrough mode" to "doesn't support the option"), there should be no change in behaviour. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30block: Move enable_write_cache to BB levelKevin Wolf1-15/+27
Whether a write cache is used or not is a decision that concerns the user (e.g. the guest device) rather than the backend. It was already logically part of the BB level as bdrv_move_feature_fields() always kept it on top of the BDS tree; with this patch, the core of it (the actual flag and the additional flushes) is also implemented there. Direct callers of bdrv_open() must pass BDRV_O_CACHE_WB now if bs doesn't have a BlockBackend attached. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30block: Always set writeback mode in blk_new_open()Kevin Wolf1-0/+4
All callers of blk_new_open() either don't rely on the WCE bit set after blk_new_open() because they explicitly set it anyway, or they pass BDRV_O_CACHE_WB unconditionally. This patch changes blk_new_open() so that it always enables writeback mode and asserts that BDRV_O_CACHE_WB is clear. For those callers that used to pass BDRV_O_CACHE_WB unconditionally, the flag is removed now. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30block: Remove blk_set_bs()Kevin Wolf1-17/+0
The function is unused since commit f21d96d0 ('block: Use BdrvChild in BlockBackend'). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-03-22util: move declarations out of qemu-common.hVeronia Bahaa1-0/+1
Move declarations out of qemu-common.h for functions declared in utils/ files: e.g. include/qemu/path.h for utils/path.c. Move inline functions out of qemu-common.h and into new files (e.g. include/qemu/bcd.h) Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-01 00:47:14 +0000