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* qcow2: allocate cluster_cache/cluster_data on demandStefan Hajnoczi2017-08-301-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | Most qcow2 files are uncompressed so it is wasteful to allocate (32 + 1) * cluster_size + 512 bytes upfront. Allocate s->cluster_cache and s->cluster_data when the first read operation is performance on a compressed cluster. The buffers are freed in .bdrv_close(). .bdrv_open() no longer has any code paths that can allocate these buffers, so remove the free functions in the error code path. This patch can result in significant memory savings when many qcow2 disks are attached or backing file chains are long: Before 12.81% (1,023,193,088B) After 5.36% (393,893,888B) Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170821135530.32344-1-stefanha@redhat.com Cc: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* qcow2: add support for LUKS encryption formatDaniel P. Berrange2017-07-111-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds support for using LUKS as an encryption format with the qcow2 file, using the new encrypt.format parameter to request "luks" format. e.g. # qemu-img create --object secret,data=123456,id=sec0 \ -f qcow2 -o encrypt.format=luks,encrypt.key-secret=sec0 \ test.qcow2 10G The legacy "encryption=on" parameter still results in creation of the old qcow2 AES format (and is equivalent to the new 'encryption-format=aes'). e.g. the following are equivalent: # qemu-img create --object secret,data=123456,id=sec0 \ -f qcow2 -o encryption=on,encrypt.key-secret=sec0 \ test.qcow2 10G # qemu-img create --object secret,data=123456,id=sec0 \ -f qcow2 -o encryption-format=aes,encrypt.key-secret=sec0 \ test.qcow2 10G With the LUKS format it is necessary to store the LUKS partition header and key material in the QCow2 file. This data can be many MB in size, so cannot go into the QCow2 header region directly. Thus the spec defines a FDE (Full Disk Encryption) header extension that specifies the offset of a set of clusters to hold the FDE headers, as well as the length of that region. The LUKS header is thus stored in these extra allocated clusters before the main image payload. Aside from all the cryptographic differences implied by use of the LUKS format, there is one further key difference between the use of legacy AES and LUKS encryption in qcow2. For LUKS, the initialiazation vectors are generated using the host physical sector as the input, rather than the guest virtual sector. This guarantees unique initialization vectors for all sectors when qcow2 internal snapshots are used, thus giving stronger protection against watermarking attacks. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-14-berrange@redhat.com Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: convert QCow2 to use QCryptoBlock for encryptionDaniel P. Berrange2017-07-111-44/+3Star
| | | | | | | | | | | | | | | | | | | | | | | This converts the qcow2 driver to make use of the QCryptoBlock APIs for encrypting image content, using the legacy QCow2 AES scheme. With this change it is now required to use the QCryptoSecret object for providing passwords, instead of the current block password APIs / interactive prompting. $QEMU \ -object secret,id=sec0,file=/home/berrange/encrypted.pw \ -drive file=/home/berrange/encrypted.qcow2,encrypt.key-secret=sec0 The test 087 could be simplified since there is no longer a difference in behaviour when using blockdev_add with encrypted images for the running vs stopped CPU state. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-12-berrange@redhat.com Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: make qcow2_encrypt_sectors encrypt in placeDaniel P. Berrange2017-07-111-11/+6Star
| | | | | | | | | | | | Instead of requiring separate input/output buffers for encrypting data, change qcow2_encrypt_sectors() to assume use of a single buffer, encrypting in place. The current callers all used the same buffer for input/output already. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-11-berrange@redhat.com Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Use offset_into_cluster() and offset_to_l2_index()Alberto Garcia2017-06-261-2/+2
| | | | | | | | | We already have functions for doing these calculations, so let's use them instead of doing everything by hand. This makes the code a bit more readable. Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Merge the writing of the COW regions with the guest dataAlberto Garcia2017-06-261-10/+30
| | | | | | | | | | | | | | | If the guest tries to write data that results on the allocation of a new cluster, instead of writing the guest data first and then the data from the COW regions, write everything together using one single I/O operation. This can improve the write performance by 25% or more, depending on several factors such as the media type, the cluster size and the I/O request size. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Pass a QEMUIOVector to do_perform_cow_{read,write}()Alberto Garcia2017-06-261-27/+24Star
| | | | | | | | | | | | | Instead of passing a single buffer pointer to do_perform_cow_write(), pass a QEMUIOVector. This will allow us to merge the write requests for the COW regions and the actual data into a single one. Although do_perform_cow_read() does not strictly need to change its API, we're doing it here as well for consistency. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Allow reading both COW regions with only one requestAlberto Garcia2017-06-261-13/+38
| | | | | | | | | | | | | | Reading both COW regions requires two separate requests, but it's perfectly possible to merge them and perform only one. This generally improves performance, particularly on rotating disk drives. The downside is that the data in the middle region is read but discarded. This patch takes a conservative approach and only merges reads when the size of the middle region is <= 16KB. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Split do_perform_cow() into _read(), _encrypt() and _write()Alberto Garcia2017-06-261-30/+87
| | | | | | | | | | | | | | This patch splits do_perform_cow() into three separate functions to read, encrypt and write the COW regions. perform_cow() can now read both regions first, then encrypt them and finally write them to disk. The memory allocation is also done in this function now, using one single buffer large enough to hold both regions. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Make perform_cow() call do_perform_cow() twiceAlberto Garcia2017-06-261-14/+22
| | | | | | | | | | | | | | Instead of calling perform_cow() twice with a different COW region each time, call it just once and make perform_cow() handle both regions. This patch simply moves code around. The next one will do the actual reordering of the COW operations. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Use unsigned int for both members of Qcow2COWRegionAlberto Garcia2017-06-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | Qcow2COWRegion has two attributes: - The offset of the COW region from the start of the first cluster touched by the I/O request. Since it's always going to be positive and the maximum request size is at most INT_MAX, we can use a regular unsigned int to store this offset. - The size of the COW region in bytes. This is guaranteed to be >= 0, so we should use an unsigned type instead. In x86_64 this reduces the size of Qcow2COWRegion from 16 to 8 bytes. It will also help keep some assertions simpler now that we know that there are no negative numbers. The prototype of do_perform_cow() is also updated to reflect these changes. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Remove unused Error variable in do_perform_cow()Alberto Garcia2017-06-261-3/+1Star
| | | | | | | | | | | | | | | | We are using the return value of qcow2_encrypt_sectors() to detect problems but we are throwing away the returned Error since we have no way to report it to the user. Therefore we can simply get rid of the local Error variable and pass NULL instead. Alternatively we could try to figure out a way to pass the original error instead of simply returning -EIO, but that would be more invasive, so let's keep the current approach. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Tweak error message related to qemu-img amendEric Blake2017-05-291-1/+2
| | | | | | | | | | | | | | | When converting a 1.1 image down to 0.10, qemu-iotests 060 forces a contrived failure where allocating a cluster used to replace a zero cluster reads unaligned data. Since it is a zero cluster rather than a data cluster being converted, changing the error message to match our earlier change in 'qcow2: Make distinction between zero cluster types obvious' is worthwhile. Suggested-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Message-id: 20170508171302.17805-1-eblake@redhat.com [mreitz: Commit message fixes] Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Discard/zero clusters by byte countEric Blake2017-05-111-20/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Passing a byte offset, but sector count, when we ultimately want to operate on cluster granularity, is madness. Clean up the external interfaces to take both offset and count as bytes, while still keeping the assertion added previously that the caller must align the values to a cluster. Then rename things to make sure backports don't get confused by changed units: instead of qcow2_discard_clusters() and qcow2_zero_clusters(), we now have qcow2_cluster_discard() and qcow2_cluster_zeroize(). The internal functions still operate on clusters at a time, and return an int for number of cleared clusters; but on an image with 2M clusters, a single L2 table holds 256k entries that each represent a 2M cluster, totalling well over INT_MAX bytes if we ever had a request for that many bytes at once. All our callers currently limit themselves to 32-bit bytes (and therefore fewer clusters), but by making this function 64-bit clean, we have one less place to clean up if we later improve the block layer to support 64-bit bytes through all operations (with the block layer auto-fragmenting on behalf of more-limited drivers), rather than the current state where some interfaces are artificially limited to INT_MAX at a time. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170507000552.20847-13-eblake@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Assert that cluster operations are alignedEric Blake2017-05-111-4/+11
| | | | | | | | | | | | | | We already audited (in commit 0c1bd469) that qcow2_discard_clusters() is only passed cluster-aligned start values; but we can further tighten the assertion that the only unaligned end value is at EOF. Recent commits have taken advantage of an unaligned tail cluster, for both discard and write zeroes. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170507000552.20847-12-eblake@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Optimize zero_single_l2() to minimize L2 churnEric Blake2017-05-111-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similar to discard_single_l2(), we should try to avoid dirtying the L2 cache when the cluster we are changing already has the right characteristics. Note that by the time we get to zero_single_l2(), BDRV_REQ_MAY_UNMAP is a requirement to unallocate a cluster (this is because the block layer clears that flag if discard.* flags during open requested that we never punch holes - see the conversation around commit 170f4b2e, https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg07306.html). Therefore, this patch can only reuse a zero cluster as-is if either unmapping is not requested, or if the zero cluster was not associated with an allocation. Technically, there are some cases where an unallocated cluster already reads as all zeroes (namely, when there is no backing file [easy: check bs->backing], or when the backing file also reads as zeroes [harder: we can't check bdrv_get_block_status since we are already holding the lock]), where the guest would not immediately see a difference if we left that cluster unallocated. But if the user did not request unmapping, leaving an unallocated cluster is wrong; and even if the user DID request unmapping, keeping a cluster unallocated risks a subtle semantic change of guest-visible contents if a backing file is later added, and it is not worth auditing whether all internal uses such as mirror properly avoid an unmap request. Thus, this patch is intentionally limited to just clusters that are already marked as zero. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170507000552.20847-8-eblake@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Make distinction between zero cluster types obviousEric Blake2017-05-111-49/+30Star
| | | | | | | | | | | | | | | | | | | | | | Treat plain zero clusters differently from allocated ones, so that we can simplify the logic of checking whether an offset is present. Do this by splitting QCOW2_CLUSTER_ZERO into two new enums, QCOW2_CLUSTER_ZERO_PLAIN and QCOW2_CLUSTER_ZERO_ALLOC. I tried to arrange the enum so that we could use 'ret <= QCOW2_CLUSTER_ZERO_PLAIN' for all unallocated types, and 'ret >= QCOW2_CLUSTER_ZERO_ALLOC' for allocated types, although I didn't actually end up taking advantage of the layout. In many cases, this leads to simpler code, by properly combining cases (sometimes, both zero types pair together, other times, plain zero is more like unallocated while allocated zero is more like normal). Signed-off-by: Eric Blake <eblake@redhat.com> Message-id: 20170507000552.20847-7-eblake@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Name typedef for cluster typeEric Blake2017-05-111-10/+11
| | | | | | | | | | | | | | | | | | Although it doesn't add all that much type safety (this is C, after all), it does add a bit of legibility to use the name QCow2ClusterType instead of a plain int. In particular, qcow2_get_cluster_offset() has an overloaded return type; a QCow2ClusterType on success, and -errno on failure; keeping the cluster type in a separate variable makes it slightly easier for the next patch to make further computations based on the type. Suggested-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Message-id: 20170507000552.20847-6-eblake@redhat.com [mreitz: Use the new type in two more places (one of them pulled from the next patch)] Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Correctly report status of preallocated zero clustersEric Blake2017-05-111-10/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | We were throwing away the preallocation information associated with zero clusters. But we should be matching the well-defined semantics in bdrv_get_block_status(), where (BDRV_BLOCK_ZERO | BDRV_BLOCK_OFFSET_VALID) informs the user which offset is reserved, while still reminding the user that reading from that offset is likely to read garbage. count_contiguous_clusters_by_type() is now used only for unallocated cluster runs, hence it gets renamed and tightened. Making this change lets us see which portions of an image are zero but preallocated, when using qemu-img map --output=json. The --output=human side intentionally ignores all zero clusters, whether or not they are preallocated. The fact that there is no change to qemu-iotests './check -qcow2' merely means that we aren't yet testing this aspect of qemu-img; a later patch will add a test. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170507000552.20847-5-eblake@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Use consistent switch indentationEric Blake2017-05-111-16/+16
| | | | | | | | | | | Fix a couple of inconsistent indentations, before an upcoming patch further tweaks the switch statements. (best viewed with 'git diff -b'). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170507000552.20847-3-eblake@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Discard preallocated zero clustersMax Reitz2017-05-111-1/+2
| | | | | | | | | | | | In discard_single_l2(), we completely discard normal clusters instead of simply turning them into preallocated zero clusters. That means we should probably do the same with such preallocated zero clusters: Discard them instead of keeping them allocated. Reported-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Reuse preallocated zero clustersMax Reitz2017-05-111-24/+56
| | | | | | | | | | | | | | | | Instead of just freeing preallocated zero clusters and completely allocating them from scratch, reuse them. We cannot do this in handle_copied(), however, since this is a COW operation. Therefore, we have to add the new logic to handle_alloc() and simply return the existing offset if it exists. The only catch is that we have to convince qcow2_alloc_cluster_link_l2() not to free the old clusters (because we have reused them). Reported-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Discard unaligned tail when wiping imageEric Blake2017-04-031-6/+4Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a subtle difference between the fast (qcow2v3 with no extra data) and slow path (qcow2v2 format [aka 0.10], or when a snapshot is present) of qcow2_make_empty(). The slow path fails to discard the final (partial) cluster of an unaligned image. The problem stems from the fact that qcow2_discard_clusters() was silently ignoring sub-cluster head and tail on unaligned requests. A quick audit of all callers shows that qcow2_snapshot_create() has always passed a cluster-aligned request since the call was added in commit 1ebf561; qcow2_co_pdiscard() has passed a cluster-aligned request since commit ecdbead taught the block layer about preferred discard alignment; and qcow2_make_empty() was fixed to pass an aligned start (but not necessarily end) in commit a3e1505. Asserting that the start is always aligned also points out that we now have a dead check: rounding the end offset down can never result in a value less than the aligned start offset (the check was rendered dead with commit ecdbead). Meanwhile, we do not want to round the end cluster down in the one case of the end offset matching the (unaligned) file size - that final partial cluster should still be discarded. With those fixes in place, the fast and slow paths are back in sync at discarding an entire image; the next patch will update qemu-iotests to ensure we don't regress. Note that bdrv_co_pdiscard ignores ALL partial cluster requests, including the partial cluster at the end of an image; it can be argued that the partial cluster at the end should be special-cased so that a guest issuing discard requests at proper alignments everywhere else can likewise empty the entire image. But that optimization is left for another day. Signed-off-by: Eric Blake <eblake@redhat.com> Message-id: 20170331185356.2479-3-eblake@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* coroutine-lock: add mutex argument to CoQueue APIsPaolo Bonzini2017-02-211-3/+1Star
| | | | | | | | | | All that CoQueue needs in order to become thread-safe is help from an external mutex. Add this to the API. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 20170213181244.16297-6-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* qcow2: Support BDRV_REQ_MAY_UNMAPFam Zheng2016-10-241-4/+5
| | | | | | | | Handling this is similar to what is done to the L2 entry in the case of compressed clusters. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: fix encryption during cow of sectorsDaniel P. Berrange2016-09-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Broken in previous commit: commit aaa4d20b4972bb1a811ce929502e6741835d584e Author: Kevin Wolf <kwolf@redhat.com> Date: Wed Jun 1 15:21:05 2016 +0200 qcow2: Make copy_sectors() byte based The copy_sectors() code was originally using the 'sector' parameter for encryption, which was passed in by the caller from the QCowL2Meta.offset field (aka the guest logical offset). After the change, the code is using 'cluster_offset' which was passed in from QCow2L2Meta.alloc_offset field (aka the host physical offset). This would cause the data to be encrypted using an incorrect initialization vector which will in turn cause later reads to return garbage. Although current qcow2 built-in encryption is blocked from usage in the emulator, one could still hit this if writing to the file via qemu-{img,io,nbd} commands. Cc: qemu-stable@nongnu.org Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: avoid memcpy(dst, NULL, len)Stefan Hajnoczi2016-09-131-1/+3
| | | | | | | | | | | | | | | | | | | | Section "7.1.4 Use of library functions" in the C99 standard says: If an argument to a function has an invalid value (such as [...] a null pointer [...]) [...] the behavior is undefined. Additionally the "searching and sorting" functions are specified as requiring valid pointer values as described in 7.1.4. This patch fixes the following sanitizer errors: block/qcow2.c:1807:41: runtime error: null pointer passed as argument 2, which is declared to never be null block/qcow2-cluster.c:86:26: runtime error: null pointer passed as argument 2, which is declared to never be null Reported-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1473758138-19260-1-git-send-email-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* qcow2: Fix qcow2_get_cluster_offset()Max Reitz2016-07-131-5/+11
| | | | | | | | | | | | | | | | | | | | | | | | | Recently, qcow2_get_cluster_offset() has been changed to work with bytes instead of sectors. This invalidated some assertions and introduced a possible integer multiplication overflow. This could be reproduced using e.g. $ qemu-img create -f qcow2 -o cluster_size=1M blub.qcow2 8G Formatting 'foo.qcow2', fmt=qcow2 size=8589934592 encryption=off cluster_size=1048576 lazy_refcounts=off refcount_bits=16 $ qemu-io -c map blub.qcow2 qemu-io: qemu/block/qcow2-cluster.c:504: qcow2_get_cluster_offset: Assertion `bytes_needed <= INT_MAX' failed. [1] 20775 abort (core dumped) qemu-io -c map foo.qcow2 This patch removes the now wrong assertion, adding comments and more assertions to prove its correctness (and fixing the overflow which would become apparent with the original assertion removed). Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160620142623.24471-3-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Avoid making the L1 table too bigMax Reitz2016-07-131-1/+2
| | | | | | | | | | | | We refuse to open images whose L1 table we deem "too big". Consequently, we should not produce such images ourselves. Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160615153630.2116-3-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> [mreitz: Added QEMU_BUILD_BUG_ON()] Signed-off-by: Max Reitz <mreitz@redhat.com>
* block/qcow2: Don't use cpu_to_*w()Peter Maydell2016-07-051-1/+1
| | | | | | | | | | | | Don't use the cpu_to_*w() functions, which we are trying to deprecate. Instead either just use cpu_to_*() to do the byteswap, or use st*_be_p() if we need to do the store somewhere other than to a variable that's already the correct type. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1466093177-17890-1-git-send-email-peter.maydell@linaro.org Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: Convert bdrv_co_preadv/pwritev to BdrvChildKevin Wolf2016-07-051-1/+1
| | | | | | | | | | | | | | | | | | | 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>
* block: Convert bdrv_pwrite_zeroes() to BdrvChildKevin Wolf2016-07-051-1/+1
| | | | | | Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Convert bdrv_pwrite(v/_sync) to BdrvChildKevin Wolf2016-07-051-3/+3
| | | | | | Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Convert bdrv_write() to BdrvChildKevin Wolf2016-07-051-1/+1
| | | | | Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Convert bdrv_read() to BdrvChildKevin Wolf2016-07-051-3/+3
| | | | | | Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* coccinelle: Remove unnecessary variables for function return valueEduardo Habkost2016-06-201-4/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Use Coccinelle script to replace 'ret = E; return ret' with 'return E'. The script will do the substitution only when the function return type and variable type are the same. Manual fixups: * audio/audio.c: coding style of "read (...)" and "write (...)" * block/qcow2-cluster.c: wrap line to make it shorter * block/qcow2-refcount.c: change indentation of wrapped line * target-tricore/op_helper.c: fix coding style of "remainder|quotient" * target-mips/dsp_helper.c: reverted changes because I don't want to argue about checkpatch.pl * ui/qemu-pixman.c: fix line indentation * block/rbd.c: restore blank line between declarations and statements Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Message-Id: <1465855078-19435-4-git-send-email-ehabkost@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Unused Coccinelle rule name dropped along with a redundant comment; whitespace touched up in block/qcow2-cluster.c; stale commit message paragraph deleted] Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qcow2: Implement .bdrv_co_pwritev()Kevin Wolf2016-06-161-7/+6Star
| | | | | | | | | | | | This changes qcow2 to implement the byte-based .bdrv_co_pwritev interface rather than the sector-based old one. As preallocation uses the same allocation function as normal writes, and the interface of that function needs to be changed, it is converted in the same patch. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* qcow2: Use bytes instead of sectors for QCowL2MetaKevin Wolf2016-06-161-20/+12Star
| | | | | | | In preparation for implementing .bdrv_co_pwritev in qcow2. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* qcow2: Make copy_sectors() byte basedKevin Wolf2016-06-161-28/+27Star
| | | | | | | | | | | This will allow copy on write operations where the overwritten part of the cluster is not aligned to sector boundaries. Also rename the function because it has nothing to do with sectors any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* qcow2: Implement .bdrv_co_preadv()Kevin Wolf2016-06-161-15/+12Star
| | | | | | | | | | | | Reading from qcow2 images is now byte granularity. Most of the affected code in qcow2 actually gets simpler with this change. The only exception is encryption, which is fixed on 512 bytes blocks; in order to keep this working, bs->request_alignment is set for encrypted images. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* qcow2: Work with bytes in qcow2_get_cluster_offset()Kevin Wolf2016-06-161-21/+23
| | | | | | | | | This patch changes the units that qcow2_get_cluster_offset() uses internally, without touching the interface just yet. This will be done in another patch. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* block: Switch bdrv_write_zeroes() to byte interfaceEric Blake2016-06-081-2/+1Star
| | | | | | | | Rename to bdrv_pwrite_zeroes() to let the compiler ensure we cater to the updated semantics. Do the same for bdrv_co_write_zeroes(). Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow/qcow2: Use DIV_ROUND_UPLaurent Vivier2016-06-071-2/+2
| | | | | | | | | | | | Replace (((n) + (d) - 1) /(d)) by DIV_ROUND_UP(n,d). This patch is the result of coccinelle script scripts/coccinelle/round.cocci CC: qemu-block@nongnu.org Signed-off-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
* qemu-common: stop including qemu/bswap.h from qemu-common.hPaolo Bonzini2016-05-191-0/+1
| | | | | | | Move it to the actual users. There are still a few includes of qemu/bswap.h in headers; removing them is left for future work. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* include/qemu/osdep.h: Don't include qapi/error.hMarkus Armbruster2016-03-221-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the Error typedef. Since then, we've moved to include qemu/osdep.h everywhere. Its file comment explains: "To avoid getting into possible circular include dependencies, this file should not include any other QEMU headers, with the exceptions of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which are doing a similar job to this file and are under similar constraints." qapi/error.h doesn't do a similar job, and it doesn't adhere to similar constraints: it includes qapi-types.h. That's in excess of 100KiB of crap most .c files don't actually need. Add the typedef to qemu/typedefs.h, and include that instead of qapi/error.h. Include qapi/error.h in .c files that need it and don't get it now. Include qapi-types.h in qom/object.h for uint16List. Update scripts/clean-includes accordingly. Update it further to match reality: replace config.h by config-target.h, add sysemu/os-posix.h, sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h comment quoted above similarly. This reduces the number of objects depending on qapi/error.h from "all of them" to less than a third. Unfortunately, the number depending on qapi-types.h shrinks only a little. More work is needed for that one. Signed-off-by: Markus Armbruster <armbru@redhat.com> [Fix compilation without the spice devel packages. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* block: Clean up includesPeter Maydell2016-01-201-0/+1
| | | | | | | | | | | 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>
* block: Add opaque value to the amend CBMax Reitz2015-12-181-6/+8
| | | | | | | | | | | Add an opaque value which is to be passed to the bdrv_amend_options() status callback. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Fix qcow2_get_cluster_offset() for zero clustersKevin Wolf2015-11-111-6/+9
| | | | | | | | | | | | | When searching for contiguous zero clusters, we only need to check the cluster type. Before this patch, an increasing offset (L2E_OFFSET_MASK) was expected, so that the function never returned more than a single zero cluster in practice. This patch fixes it to actually return as many contiguous zero clusters as it can. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1446657384-5907-1-git-send-email-kwolf@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: Convert bs->backing_hd to BdrvChildKevin Wolf2015-10-161-2/+2
| | | | | | | | | | | | | | | 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>
* block: Convert bs->file to BdrvChildKevin Wolf2015-10-161-16/+21
| | | | | | | | | | | 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>