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2017-10-06qcow2: truncate the tail of the image file after shrinking the imagePavel Butsykin1-0/+23
Now after shrinking the image, at the end of the image file, there might be a tail that probably will never be used. So we can find the last used cluster and cut the tail. Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20170929121613.25997-3-pbutsykin@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06qcow2: fix return error code in qcow2_truncate()Pavel Butsykin1-2/+2
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170929121613.25997-2-pbutsykin@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06block: convert qcrypto_block_encrypt|decrypt to take bytes offsetDaniel P. Berrange1-2/+2
Instead of sector offset, take the bytes offset when encrypting or decrypting data. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170927125340.12360-6-berrange@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06qcow2: Switch qcow2_measure() to byte-based iterationEric Blake1-12/+10
This is new code, but it is easier to read if it makes passes over the image using bytes rather than sectors (and will get easier in the future when bdrv_get_block_status is converted to byte-based). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-09-26qcow2: add shrink image supportPavel Butsykin1-9/+34
This patch add shrinking of the image file for qcow2. As a result, this allows us to reduce the virtual image size and free up space on the disk without copying the image. Image can be fragmented and shrink is done by punching holes in the image file. Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20170918124230.8152-4-pbutsykin@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-09-19Convert remaining error_report() to warn_report()Alistair Francis1-4/+5
In a previous patch (3dc6f8693694a649a9c83f1e2746565b47683923) we converted uses of error_report("warning:"... to use warn_report() instead. This was to help standardise on a single method of printing warnings to the user. There appears to have been some cases that slipped through in patch sets applied around the same time, this patch catches the few remaining cases. All of the warnings were changed using this command: find ./* -type f -exec sed -i \ 's|error_report(".*warning[,:] |warn_report("|Ig' {} + Indentation fixed up manually afterwards. Two messages were manually fixed up as well. Signed-off-by: Alistair Francis <alistair.francis@xilinx.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Max Reitz <mreitz@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Alexander Graf <agraf@suse.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-Id: <eec8cba0d5434bd828639e5e45f12182490ff47d.1505158760.git.alistair.francis@xilinx.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-06qcow2: move qcow2_store_persistent_dirty_bitmaps() before cache flushingPavel Butsykin1-8/+8
After calling qcow2_inactivate(), all qcow2 caches must be flushed, but this may not happen, because the last call qcow2_store_persistent_dirty_bitmaps() can lead to marking l2/refcont cache as dirty. Let's move qcow2_store_persistent_dirty_bitmaps() before the caсhe flushing to fix it. Cc: qemu-stable@nongnu.org Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-09-04qapi: Change data type of the FOO_lookup generated for enum FOOMarc-André Lureau1-2/+2
Currently, a FOO_lookup is an array of strings terminated by a NULL sentinel. A future patch will generate enums with "holes". NULL-termination will cease to work then. To prepare for that, store the length in the FOO_lookup by wrapping it in a struct and adding a member for the length. The sentinel will be dropped next. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20170822132255.23945-13-marcandre.lureau@redhat.com> [Basically redone] Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1503564371-26090-16-git-send-email-armbru@redhat.com> [Rebased]
2017-09-04qapi: Mechanically convert FOO_lookup[...] to FOO_str(...)Markus Armbruster1-2/+2
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1503564371-26090-14-git-send-email-armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-09-04qapi: Generate FOO_str() macro for QAPI enum FOOMarkus Armbruster1-1/+0
The next commit will put it to use. May look pointless now, but we're going to change the FOO_lookup's type, and then it'll help. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1503564371-26090-13-git-send-email-armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-09-04qapi: Drop superfluous qapi_enum_parse() parameter maxMarkus Armbruster1-4/+2
The lookup tables have a sentinel, no need to make callers pass their size. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1503564371-26090-3-git-send-email-armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> [Rebased, commit message corrected]
2017-08-30qcow2: allocate cluster_cache/cluster_data on demandStefan Hajnoczi1-12/+0
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>
2017-08-30misc: Remove unused Error variablesAlberto Garcia1-6/+2
There's a few cases which we're passing an Error pointer to a function only to discard it immediately afterwards without checking it. In these cases we can simply remove the variable and pass NULL instead. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20170829120836.16091-1-berto@igalia.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-11qcow2: Check failure of bdrv_getlength()Eric Blake1-1/+4
qcow2_co_pwritev_compressed() should not call bdrv_truncate() if determining the size failed. Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-08-11qcow2: Drop debugging dump_refcounts()Eric Blake1-21/+0
It's been #if 0'd since its introduction in 2006, commit 585f8587. We can revive dead code if we need it, but in the meantime, it has bit-rotted (for example, not checking for failure in bdrv_getlength()). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-07-25qcow: fix memory leaks related to encryptionDaniel P. Berrange1-3/+4
Fix leak of the 'encryptopts' string, which was mistakenly declared const. Fix leak of QemuOpts entry which should not have been deleted from the opts array. Reported by: coverity Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170714103105.5781-1-berrange@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-24qcow2: Fix sector calculation in qcow2_measure()Eric Blake1-2/+2
We used MAX() instead of the intended MIN() when computing how many sectors to view in the current loop iteration of qcow2_measure(), and passed in a value of INT_MAX sectors instead of our more usual limit of BDRV_REQUEST_MAX_SECTORS (the latter avoids 32-bit overflow on conversion to bytes). For small files, the bug is harmless: bdrv_get_block_status_above() clamps its *pnum answer to the BDS size, regardless of any insanely larger input request. However, for any file at least 2T in size, we can very easily end up going into an infinite loop (the maximum of 0x100000000 sectors and INT_MAX is a 64-bit quantity, which becomes 0 when assigned to int; once nb_sectors is 0, we never make progress). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-07-17qcow2: call CoQueue APIs under CoMutexPaolo Bonzini1-2/+2
Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20170629132749.997-2-pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
2017-07-11block/qcow2: falloc/full preallocating growthMax Reitz1-1/+99
Implement the preallocation modes falloc and full for growing qcow2 images. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20170613202107.10125-15-mreitz@redhat.com Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block/qcow2: Add qcow2_refcount_area()Max Reitz1-4/+16
This function creates a collection of self-describing refcount structures (including a new refcount table) at the end of a qcow2 image file. Optionally, these structures can also describe a number of additional clusters beyond themselves; this will be important for preallocated truncation, which will place the data clusters and L2 tables there. For now, we can use this function to replace the part of alloc_refcount_block() that grows the refcount table (from which it is actually derived). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170613202107.10125-13-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block/qcow2: Metadata preallocation for truncateMax Reitz1-2/+31
We can support PREALLOC_MODE_METADATA by invoking preallocate() in qcow2_truncate(). Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20170613202107.10125-12-mreitz@redhat.com Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block/qcow2: Lock s->lock in preallocate()Max Reitz1-7/+15
preallocate() is and will be called only from places that do not otherwise need to lock s->lock: Currently that is qcow2_create2(), as of a future patch it will be called from qcow2_truncate(), too. It therefore makes sense to move locking that mutex into preallocate() itself. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170613202107.10125-11-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block/qcow2: Generalize preallocate()Max Reitz1-5/+12
This patch adds two new parameters to the preallocate() function so we will be able to use it not just for preallocating a new image but also for preallocated image growth. The offset parameter allows the caller to specify a virtual offset from which to start preallocating. For newly created images this is always 0, but for preallocating growth this will be the old image length. The new_length parameter specifies the supposed new length of the image (basically the "end offset" for preallocation). During image truncation, bdrv_getlength() will return the old image length so we cannot rely on its return value then. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170613202107.10125-10-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block: Add PreallocMode to blk_truncate()Max Reitz1-2/+2
blk_truncate() itself will pass that value to bdrv_truncate(), and all callers of blk_truncate() just set the parameter to PREALLOC_MODE_OFF for now. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170613202107.10125-4-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block: Add PreallocMode to bdrv_truncate()Max Reitz1-2/+2
For block drivers that just pass a truncate request to the underlying protocol, we can now pass the preallocation mode instead of aborting if it is not PREALLOC_MODE_OFF. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170613202107.10125-3-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block: Add PreallocMode to BD.bdrv_truncate()Max Reitz1-1/+8
Add a PreallocMode parameter to the bdrv_truncate() function implemented by each block driver. Currently, we always pass PREALLOC_MODE_OFF and no driver accepts anything else. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170613202107.10125-2-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: add bdrv_measure() supportStefan Hajnoczi1-0/+137
Use qcow2_calc_prealloc_size() to get the required file size. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20170705125738.8777-7-stefanha@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: extract image creation option parsingStefan Hajnoczi1-36/+73
The image creation options parsed by qcow2_create() are also needed to implement .bdrv_measure(). Extract the parsing code, including input validation. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20170705125738.8777-6-stefanha@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: make refcount size calculation conservativeStefan Hajnoczi1-41/+42
The refcount metadata size calculation is inaccurate and can produce numbers that are too small. This is bad because we should calculate a conservative number - one that is guaranteed to be large enough. This patch switches the approach to a fixed point calculation because the existing equation is hard to solve when inaccuracies are taken care of. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20170705125738.8777-5-stefanha@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: extract preallocation calculation functionStefan Hajnoczi1-59/+77
Calculating the preallocated image size will be needed to implement .bdrv_measure(). Extract the code out into a separate function. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20170705125738.8777-4-stefanha@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: add .bdrv_remove_persistent_dirty_bitmapVladimir Sementsov-Ogievskiy1-0/+1
Realize .bdrv_remove_persistent_dirty_bitmap interface. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20170628120530.31251-29-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: add .bdrv_can_store_new_dirty_bitmapVladimir Sementsov-Ogievskiy1-0/+1
Realize .bdrv_can_store_new_dirty_bitmap interface. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170628120530.31251-23-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: store bitmaps on reopening image as read-onlyVladimir Sementsov-Ogievskiy1-0/+5
Store bitmaps and mark them read-only on reopening image as read-only. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170628120530.31251-21-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: add persistent dirty bitmaps supportVladimir Sementsov-Ogievskiy1-0/+9
Store persistent dirty bitmaps in qcow2 image. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170628120530.31251-20-vsementsov@virtuozzo.com [mreitz: Always assign ret in store_bitmap() in case of an error] Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: support .bdrv_reopen_bitmaps_rwVladimir Sementsov-Ogievskiy1-0/+2
Realize bdrv_reopen_bitmaps_rw interface. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170628120530.31251-15-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: autoloading dirty bitmapsVladimir Sementsov-Ogievskiy1-2/+15
Auto loading bitmaps are bitmaps in Qcow2, with the AUTO flag set. They are loaded when the image is opened and become BdrvDirtyBitmaps for the corresponding drive. Extra data in bitmaps is not supported for now. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20170628120530.31251-12-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: add bitmaps extensionVladimir Sementsov-Ogievskiy1-5/+120
Add bitmap extension as specified in docs/specs/qcow2.txt. For now, just mirror extension header into Qcow2 state and check constraints. Also, calculate refcounts for qcow2 bitmaps, to not break qemu-img check. For now, disable image resize if it has bitmaps. It will be fixed later. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20170628120530.31251-9-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: report encryption specific image informationDaniel P. Berrange1-1/+31
Currently 'qemu-img info' reports a simple "encrypted: yes" field. This is not very useful now that qcow2 can support multiple encryption formats. Users want to know which format is in use and some data related to it. Wire up usage of the qcrypto_block_get_info() method so that 'qemu-img info' can report about the encryption format and parameters in use $ qemu-img create \ --object secret,id=sec0,data=123456 \ -o encrypt.format=luks,encrypt.key-secret=sec0 \ -f qcow2 demo.qcow2 1G Formatting 'demo.qcow2', fmt=qcow2 size=1073741824 \ encryption=off encrypt.format=luks encrypt.key-secret=sec0 \ cluster_size=65536 lazy_refcounts=off refcount_bits=16 $ qemu-img info demo.qcow2 image: demo.qcow2 file format: qcow2 virtual size: 1.0G (1073741824 bytes) disk size: 480K encrypted: yes cluster_size: 65536 Format specific information: compat: 1.1 lazy refcounts: false refcount bits: 16 encrypt: ivgen alg: plain64 hash alg: sha256 cipher alg: aes-256 uuid: 3fa930c4-58c8-4ef7-b3c5-314bb5af21f3 format: luks cipher mode: xts slots: [0]: active: true iters: 1839058 key offset: 4096 stripes: 4000 [1]: active: false key offset: 262144 [2]: active: false key offset: 520192 [3]: active: false key offset: 778240 [4]: active: false key offset: 1036288 [5]: active: false key offset: 1294336 [6]: active: false key offset: 1552384 [7]: active: false key offset: 1810432 payload offset: 2068480 master key iters: 438487 corrupt: false With the legacy "AES" encryption we just report the format name $ qemu-img create \ --object secret,id=sec0,data=123456 \ -o encrypt.format=aes,encrypt.key-secret=sec0 \ -f qcow2 demo.qcow2 1G Formatting 'demo.qcow2', fmt=qcow2 size=1073741824 \ encryption=off encrypt.format=aes encrypt.key-secret=sec0 \ cluster_size=65536 lazy_refcounts=off refcount_bits=16 $ ./qemu-img info demo.qcow2 image: demo.qcow2 file format: qcow2 virtual size: 1.0G (1073741824 bytes) disk size: 196K encrypted: yes cluster_size: 65536 Format specific information: compat: 1.1 lazy refcounts: false refcount bits: 16 encrypt: format: aes corrupt: false Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-20-berrange@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block: pass option prefix down to crypto layerDaniel P. Berrange1-4/+4
While the crypto layer uses a fixed option name "key-secret", the upper block layer may have a prefix on the options. e.g. "encrypt.key-secret", in order to avoid clashes between crypto option names & other block option names. To ensure the crypto layer can report accurate error messages, we must tell it what option name prefix was used. Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-19-berrange@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11block: remove all encryption handling APIsDaniel P. Berrange1-1/+0
Now that all encryption keys must be provided upfront via the QCryptoSecret API and associated block driver properties there is no need for any explicit encryption handling APIs in the block layer. Encryption can be handled transparently within the block driver. We only retain an API for querying whether an image is encrypted or not, since that is a potentially useful piece of metadata to report to the user. Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-18-berrange@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11qcow2: add support for LUKS encryption formatDaniel P. Berrange1-31/+237
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>
2017-07-11qcow2: convert QCow2 to use QCryptoBlock for encryptionDaniel P. Berrange1-74/+152
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>
2017-07-11qcow2: make qcow2_encrypt_sectors encrypt in placeDaniel P. Berrange1-2/+2
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>
2017-07-11block: deprecate "encryption=on" in favor of "encrypt.format=aes"Daniel P. Berrange1-7/+27
Historically the qcow & qcow2 image formats supported a property "encryption=on" to enable their built-in AES encryption. We'll soon be supporting LUKS for qcow2, so need a more general purpose way to enable encryption, with a choice of formats. This introduces an "encrypt.format" option, which will later be joined by a number of other "encrypt.XXX" options. The use of a "encrypt." prefix instead of "encrypt-" is done to facilitate mapping to a nested QAPI schema at later date. e.g. the preferred syntax is now qemu-img create -f qcow2 -o encrypt.format=aes demo.qcow2 Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170623162419.26068-8-berrange@redhat.com Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26block: change variable names in BlockDriverStateManos Pitsidianakis1-14/+14
Change the 'int count' parameter in *pwrite_zeros, *pdiscard related functions (and some others) to 'int bytes', as they both refer to bytes. This helps with code legibility. Signed-off-by: Manos Pitsidianakis <el13635@mail.ntua.gr> Message-id: 20170609101808.13506-1-el13635@mail.ntua.gr Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26qcow2: Use offset_into_cluster() and offset_to_l2_index()Alberto Garcia1-1/+1
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>
2017-06-26qcow2: Merge the writing of the COW regions with the guest dataAlberto Garcia1-10/+54
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>
2017-05-29qcow2: remove extra local_error variableAlberto Garcia1-3/+2
Commit d7086422b1c1e75e320519cfe26176db6ec97a37 added a local_err variable global to the qcow2_amend_options() function, so there's no need to have this other one. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: 20170511150337.21470-1-berto@igalia.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-05-11qcow2: Discard/zero clusters by byte countEric Blake1-13/+9
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>
2017-05-11qcow2: Optimize write zero of unaligned tail clusterEric Blake1-0/+7
We've already improved discards to operate efficiently on the tail of an unaligned qcow2 image; it's time to make a similar improvement to write zeroes. The special case is only valid at the tail cluster of a file, where we must recognize that any sectors beyond the image end would implicitly read as zero, and therefore should not penalize our logic for widening a partial cluster into writing the whole cluster as zero. However, note that for now, the special case of end-of-file is only recognized if there is no backing file, or if the backing file has the same length; that's because when the backing file is shorter than the active layer, we don't have code in place to recognize that reads of a sector unallocated at the top and beyond the backing end-of-file are implicitly zero. It's not much of a real loss, because most people don't use images that aren't cluster-aligned, or where the active layer is a different size than the backing layer (especially where the difference falls within a single cluster). Update test 154 to cover the new scenarios, using two images of intentionally differing length. While at it, fix the test to gracefully skip when run as ./check -qcow2 -o compat=0.10 154 since the older format lacks zero clusters already required earlier in the test. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20170507000552.20847-11-eblake@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>