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2017-10-06iotests: Fix 195 if IMGFMT is part of TEST_DIRMax Reitz1-3/+4
do_run_qemu() in iotest 195 first applies _filter_imgfmt when printing qemu's command line and _filter_testdir only afterwards. Therefore, if the image format is part of the test directory path, _filter_testdir will no longer apply and the actual output will differ from the reference output even in case of success. For example, TEST_DIR might be "/tmp/test-qcow2", in which case _filter_imgfmt first transforms this to "/tmp/test-IMGFMT" which is no longer recognized as the TEST_DIR by _filter_testdir. Fix this by not applying _filter_imgfmt in do_run_qemu() but in run_qemu() instead, and only after _filter_testdir. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20170927211334.3988-1-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06block/mirror: check backing in bdrv_mirror_top_refresh_filenameVladimir Sementsov-Ogievskiy1-0/+5
Backing may be zero after failed bdrv_attach_child in bdrv_set_backing_hd, which leads to SIGSEGV. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-id: 20170928120300.58164-1-vsementsov@virtuozzo.com Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06block: support passthrough of BDRV_REQ_FUA in crypto driverDaniel P. Berrange1-2/+5
The BDRV_REQ_FUA flag can trivially be allowed in the crypt driver as a passthrough to the underlying block driver. 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: 20170927125340.12360-7-berrange@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06block: convert qcrypto_block_encrypt|decrypt to take bytes offsetDaniel P. Berrange9-41/+56
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>
2017-10-06block: convert crypto driver to bdrv_co_preadv|pwritevDaniel P. Berrange1-52/+54
Make the crypto driver implement the bdrv_co_preadv|pwritev callbacks, and also use bdrv_co_preadv|pwritev for I/O with the protocol driver beneath. This replaces sector based I/O with byte based I/O, and allows us to stop assuming the physical sector size matches the encryption sector size. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170927125340.12360-5-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>
2017-10-06block: fix data type casting for crypto payload offsetDaniel P. Berrange1-4/+9
The crypto APIs report the offset of the data payload as an uint64_t type, but the block driver is casting to size_t or ssize_t which will potentially truncate. Most of the block APIs use int64_t for offsets meanwhile, so even if using uint64_t in the crypto block driver we are still at risk of truncation. Change the block crypto driver to use uint64_t, but add asserts that the value is less than INT64_MAX. 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: 20170927125340.12360-4-berrange@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06crypto: expose encryption sector size in APIsDaniel P. Berrange5-2/+27
While current encryption schemes all have a fixed sector size of 512 bytes, this is not guaranteed to be the case in future. Expose the sector size in the APIs so the block layer can remove assumptions about fixed 512 byte sectors. 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: 20170927125340.12360-3-berrange@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-10-06block: use 1 MB bounce buffers for crypto instead of 16KBDaniel P. Berrange1-13/+15
Using 16KB bounce buffers creates a significant performance penalty for I/O to encrypted volumes on storage which high I/O latency (rotating rust & network drives), because it triggers lots of fairly small I/O operations. On tests with rotating rust, and cache=none|directsync, write speed increased from 2MiB/s to 32MiB/s, on a par with that achieved by the in-kernel luks driver. With other cache modes the in-kernel driver is still notably faster because it is able to report completion of the I/O request before any encryption is done, while the in-QEMU driver must encrypt the data before completion. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170927125340.12360-2-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>
2017-10-06iotests: Add test 197 for covering copy-on-readEric Blake4-0/+137
Add a test for qcow2 copy-on-read behavior, including exposure for the just-fixed bugs. The copy-on-read behavior is always to a qcow2 image, but the test is careful to allow running with most image protocol/format combos as the backing file being copied from (luks being the exception, as it is harder to pass the right secret to all the right places). In fact, for './check nbd', this appears to be the first time we've had a qcow2 image wrapping NBD, requiring an additional line in _filter_img_create to match the similar line in _filter_img_info. Invoking blkdebug to prove we don't write too much took some effort to get working; and it requires that $TEST_WRAP (based on $TEST_DIR) not be subject to word splitting. We may decide later to have the entire iotests suite use relative rather than absolute names, to avoid problems inherited by the absolute name of $PWD or $TEST_DIR, at which point the sanity check in this commit could be simplified. This test requires at least 2G of consecutive memory to succeed; as such, it is prone to spurious failures, particularly on 32-bit machines under load. This situation is detected and triggers an early exit to skip the test, rather than a failure. To manually provoke this setup on a beefier machine, I used: $ (ulimit -S -v 1000000; ./check -qcow2 197) Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06block: Perform copy-on-read in loopEric Blake1-38/+82
Improve our braindead copy-on-read implementation. Pre-patch, we have multiple issues: - we create a bounce buffer and perform a write for the entire request, even if the active image already has 99% of the clusters occupied, and really only needs to copy-on-read the remaining 1% of the clusters - our bounce buffer was as large as the read request, and can needlessly exhaust our memory by using double the memory of the request size (the original request plus our bounce buffer), rather than a capped maximum overhead beyond the original - if a driver has a max_transfer limit, we are bypassing the normal code in bdrv_aligned_preadv() that fragments to that limit, and instead attempt to read the entire buffer from the driver in one go, which some drivers may assert on - a client can request a large request of nearly 2G such that rounding the request out to cluster boundaries results in a byte count larger than 2G. While this cannot exceed 32 bits, it DOES have some follow-on problems: -- the call to bdrv_driver_pread() can assert for exceeding BDRV_REQUEST_MAX_BYTES, if the driver is old and lacks .bdrv_co_preadv -- if the buffer is all zeroes, the subsequent call to bdrv_co_do_pwrite_zeroes is a no-op due to a negative size, which means we did not actually copy on read Fix all of these issues by breaking up the action into a loop, where each iteration is capped to sane limits. Also, querying the allocation status allows us to optimize: when data is already present in the active layer, we don't need to bounce. Note that the code has a telling comment that copy-on-read should probably be a filter driver rather than a bolt-on hack in io.c; but that remains a task for another day. CC: qemu-stable@nongnu.org Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06block: Add blkdebug hook for copy-on-readEric Blake2-1/+5
Make it possible to inject errors on writes performed during a read operation due to copy-on-read semantics. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06iotests: Restore stty settings on completionEric Blake1-0/+10
Executing qemu with a terminal as stdin will temporarily alter stty settings on that terminal (for example, disabling echo), because of how we run both the monitor and any multiplexing with guest input. Normally, qemu restores the original settings on exit; but if an iotest triggers qemu to abort in the middle, we can be left with the altered terminal setup. This can make life very annoying when debugging an iotest failure (not everyone remembers the trick of blind-typing 'stty sane' without echo, and some people prefer terminal settings that are slightly different than the defaults picked by 'stty sane'). It is possible to avoid qemu corrupting the terminal by not passing a terminal to qemu's stdin in the first place (as in, use './check ... </dev/null'), but that's extra typing to have to remember. But running 'exec </dev/null' in the harness seems like it might be too heavy of a hammer. So I instead went the the solution of saving and restoring the stty settings, only when the harness detects that it is run interactively. I tested this patch by forcing an allocation failure (I can't guarantee that this particular limit will work on all setups, but it shows the idea): $ (ulimit -S -v 500000; ./check -qcow2 1) Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06block: Uniform handling of 0-length bdrv_get_block_status()Eric Blake1-0/+4
Handle a 0-length block status request up front, with a uniform return value claiming the area is not allocated. Most callers don't pass a length of 0 to bdrv_get_block_status() and friends; but it definitely happens with a 0-length read when copy-on-read is enabled. While we could audit all callers to ensure that they never make a 0-length request, and then assert that fact, it was just as easy to fix things to always report success (as long as the callers are careful to not go into an infinite loop). However, we had inconsistent behavior on whether the status is reported as allocated or defers to the backing layer, depending on what callbacks the driver implements, and possibly wasting quite a few CPU cycles to get to that answer. Consistently reporting unallocated up front doesn't really hurt anything, and makes it easier both for callers (0-length requests now have well-defined behavior) and for drivers (drivers don't have to deal with 0-length requests). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-io: Add -C for opening with copy-on-readEric Blake1-3/+12
Make it easier to enable copy-on-read during iotests, by exposing a new bool option to main and open. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06commit: Remove overlay_bsKevin Wolf4-55/+20
We don't need to make any assumptions about the graph layout above the top node of the commit operation any more. Remove the use of bdrv_find_overlay() and related variables from the commit job code. bdrv_drop_intermediate() doesn't use the 'active' parameter any more, so we can just drop it. The overlay node was previously added to the block job to get a BLK_PERM_GRAPH_MOD. We really need to respect those permissions in bdrv_drop_intermediate() now, but as long as we haven't figured out yet how BLK_PERM_GRAPH_MOD is actually supposed to work, just leave a TODO comment there. With this change, it is now possible to perform another block job on an overlay node without conflicts. qemu-iotests 030 is changed accordingly. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2017-10-06qemu-iotests: Test commit block job where top has two parentsKevin Wolf3-0/+981
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: Allow QMP pretty printing in common.qemuKevin Wolf1-3/+11
QMP responses to certain commands can become quite long, which doesn't only make reading them hard, but also means that the maximum line length in patch emails can be exceeded. Allow tests to switch to QMP pretty printing, which results in more, but shorter lines. We also need to make sure to keep indentation in the response for this to work as expected. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2017-10-06commit: Support multiple roots above top nodeKevin Wolf2-29/+41
This changes the commit block job to support operation in a graph where there is more than a single active layer that references the top node. This involves inserting the commit filter node not only on the path between the given active node and the top node, but between the top node and all of its parents. On completion, bdrv_drop_intermediate() must consider all parents for updating the backing file link. These parents may be backing files themselves and as such read-only; reopen them temporarily if necessary. Previously this was achieved by the bdrv_reopen() calls in the commit block job that made overlay_bs read-write for the whole duration of the block job, even though write access is only needed on completion. Now that we consider all parents, overlay_bs is meaningless. It is left in place in this commit, but we'll remove it soon. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06block: Introduce BdrvChildRole.update_filenameKevin Wolf2-5/+34
There is no good reason for bdrv_drop_intermediate() to know the active layer above the subchain it is operating on - even more so, because the assumption that there is a single active layer above it is not generally true. In order to prepare removal of the active parameter, use a BdrvChildRole callback to update the backing file string in the overlay image instead of directly calling bdrv_change_backing_file(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2017-10-06qemu-iotests: merge "check" and "common"Paolo Bonzini2-554/+531
"check" is full of qemu-iotests--specific details. Separating it from "common" does not make much sense anymore. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: get rid of $iamPaolo Bonzini2-5/+2
The variable is almost unused, and one of the two uses is actually uninitialized. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: fix uninitialized variablePaolo Bonzini2-2/+2
The variable is used in "common" but defined only after the file is sourced. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: disintegrate more parts of common.configPaolo Bonzini4-49/+50
Split "check" parts from tests part. For the directory setup, the actual computation of directories goes in "check", while the sanity checks go in the tests. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: do not include common.rc in "check"Paolo Bonzini2-14/+5
It only provides functions used by the test programs. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: limit non-_PROG-suffixed variables to common.rcPaolo Bonzini5-75/+75
These are never used by "check", with one exception that does not need $QEMU_OPTIONS. Keep them in common.rc, which will be soon included only by the tests. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: cleanup and fix search for programsPaolo Bonzini3-106/+73
Instead of ./check failing when a binary is missing, we try each test case now and each one fails with tons of test case diffs. Also, all the variables were initialized by "check" prior to "common" being sourced, and then (uselessly) checked for emptiness again in "check". Centralize the search for programs in "common" (which will soon be one with "check"), including the "realpath" invocation which can be done just once in "check" rather than in the tests. For qnio_server, move the detection to "common", simplifying set_prog_path to stop handling the unused second argument, and embedding the "realpath" pass. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: move "check" code out of common.rcPaolo Bonzini3-41/+36
Some functions in common.rc are never used by the tests. Move them out of that file and into common, which is already included only by "check". Code that actually *is* common to "check" and tests can be placed in common.config. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: get rid of AWK_PROGPaolo Bonzini3-6/+3
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qemu-iotests: remove dead codePaolo Bonzini4-145/+0
This includes shell function, shell variables and command line options (randomize.awk does not exist). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06hw/block/onenand: Remove dead code blockThomas Huth1-4/+0
The condition of the for-loop makes sure that b is always smaller than s->blocks, so the "if (b >= s->blocks)" statement is completely superfluous here. Buglink: https://bugs.launchpad.net/qemu/+bug/1715007 Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06dirty-bitmap: Convert internal hbitmap size/granularityEric Blake1-44/+18
Now that all callers are using byte-based interfaces, there's no reason for our internal hbitmap to remain with sector-based granularity. It also simplifies our internal scaling, since we already know that hbitmap widens requests out to granularity boundaries. 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>
2017-10-06dirty-bitmap: Switch bdrv_set_dirty() to bytesEric Blake3-8/+7
Both callers already had bytes available, but were scaling to sectors. Move the scaling to internal code. In the case of bdrv_aligned_pwritev(), we are now passing the exact offset rather than a rounded sector-aligned value, but that's okay as long as dirty bitmap widens start/bytes to granularity boundaries. 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>
2017-10-06qcow2: Switch store_bitmap_data() to byte-based iterationEric Blake2-16/+17
Now that we have adjusted the majority of the calls this function makes to be byte-based, it is easier to read the code if it makes passes over the image using bytes rather than sectors. iotests 165 was rather weak - on a default 64k-cluster image, where bitmap granularity also defaults to 64k bytes, a single cluster of the bitmap table thus covers (64*1024*8) bits which each cover 64k bytes, or 32G of image space. But the test only uses a 1G image, so it cannot trigger any more than one loop of the code in store_bitmap_data(); and it was writing to the first cluster. In order to test that we are properly aligning which portions of the bitmap are being written to the file, we really want to test a case where the first dirty bit returned by bdrv_dirty_iter_next() is not aligned to the start of a cluster, which we can do by modifying the test to write data that doesn't happen to fall in the first cluster of the image. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06qcow2: Switch load_bitmap_data() to byte-based iterationEric Blake1-14/+8
Now that we have adjusted the majority of the calls this function makes to be byte-based, it is easier to read the code if it makes passes over the image using bytes rather than sectors. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@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>
2017-10-06mirror: Switch mirror_dirty_init() to byte-based iterationEric Blake1-24/+14
Now that we have adjusted the majority of the calls this function makes to be byte-based, it is easier to read the code if it makes passes over the image using bytes rather than sectors. 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>
2017-10-06dirty-bitmap: Change bdrv_[re]set_dirty_bitmap() to use bytesEric Blake4-22/+31
Some of the callers were already scaling bytes to sectors; others can be easily converted to pass byte offsets, all in our shift towards a consistent byte interface everywhere. Making the change will also make it easier to write the hold-out callers to use byte rather than sectors for their iterations; it also makes it easier for a future dirty-bitmap patch to offload scaling over to the internal hbitmap. Although all callers happen to pass sector-aligned values, make the internal scaling robust to any sub-sector requests. 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>
2017-10-06dirty-bitmap: Change bdrv_get_dirty_locked() to take bytesEric Blake4-9/+9
Half the callers were already scaling bytes to sectors; the other half can eventually be simplified to use byte iteration. Both callers were already using the result as a bool, so make that explicit. Making the change also makes it easier for a future dirty-bitmap patch to offload scaling over to the internal hbitmap. Remember, asking whether a byte is dirty is effectively asking whether the entire granularity containing the byte is dirty, since we only track dirtiness by granularity. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06dirty-bitmap: Change bdrv_get_dirty_count() to report bytesEric Blake3-13/+9
Thanks to recent cleanups, all callers were scaling a return value of sectors into bytes; do the scaling internally instead. 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>
2017-10-06dirty-bitmap: Change bdrv_dirty_iter_next() to report byte offsetEric Blake4-7/+8
Thanks to recent cleanups, most callers were scaling a return value of sectors into bytes (the exception, in qcow2-bitmap, will be converted to byte-based iteration later). Update the interface to do the scaling internally instead. In qcow2-bitmap, the code was specifically checking for an error return of -1. To avoid a regression, we either have to make sure we continue to return -1 (rather than a scaled -512) on error, or we have to fix the caller to treat all negative values as error rather than just one magic value. It's easy enough to make both changes at the same time, even though either one in isolation would work. 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>
2017-10-06dirty-bitmap: Set iterator start by offset, not sectorEric Blake5-15/+12
All callers to bdrv_dirty_iter_new() passed 0 for their initial starting point, drop that parameter. Most callers to bdrv_set_dirty_iter() were scaling a byte offset to a sector number; the exception qcow2-bitmap will be converted later to use byte rather than sector iteration. Move the scaling to occur internally to dirty bitmap code instead, so that callers now pass in bytes. 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>
2017-10-06qcow2: Switch sectors_covered_by_bitmap_cluster() to byte-basedEric Blake1-14/+14
We are gradually converting to byte-based interfaces, as they are easier to reason about than sector-based. Change the qcow2 bitmap helper function sectors_covered_by_bitmap_cluster(), renaming it to bytes_covered_by_bitmap_cluster() in the process. 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>
2017-10-06dirty-bitmap: Change bdrv_dirty_bitmap_*serialize*() to take bytesEric Blake3-28/+45
Right now, the dirty-bitmap code exposes the fact that we use a scale of sector granularity in the underlying hbitmap to anything that wants to serialize a dirty bitmap. It's nicer to uniformly expose bytes as our dirty-bitmap interface, matching the previous change to bitmap size. The only caller to serialization is currently qcow2-cluster.c, which becomes a bit more verbose because it is still tracking sectors for other reasons, but a later patch will fix that to more uniformly use byte offsets everywhere. Likewise, within dirty-bitmap, we have to add more assertions that we are not truncating incorrectly, which can go away once the internal hbitmap is byte-based rather than sector-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>
2017-10-06dirty-bitmap: Track bitmap size by bytesEric Blake1-12/+14
We are still using an internal hbitmap that tracks a size in sectors, with the granularity scaled down accordingly, because it lets us use a shortcut for our iterators which are currently sector-based. But there's no reason we can't track the dirty bitmap size in bytes, since it is (mostly) an internal-only variable (remember, the size is how many bytes are covered by the bitmap, not how many bytes the bitmap occupies). A later cleanup will convert dirty bitmap internals to be entirely byte-based, eliminating the intermediate sector rounding added here; and technically, since bdrv_getlength() already rounds up to sectors, our use of DIV_ROUND_UP is more for theoretical completeness than for any actual rounding. Use is_power_of_2() while at it, instead of open-coding that. 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>
2017-10-06dirty-bitmap: Change bdrv_dirty_bitmap_size() to report bytesEric Blake2-7/+9
We're already reporting bytes for bdrv_dirty_bitmap_granularity(); mixing bytes and sectors in our return values is a recipe for confusion. A later cleanup will convert dirty bitmap internals to be entirely byte-based, but in the meantime, we should report the bitmap size in bytes. The only external caller in qcow2-bitmap.c is temporarily more verbose (because it is still using sector-based math), but will later be switched to track progress by bytes instead of sectors. 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>
2017-10-06dirty-bitmap: Avoid size query failure during truncateEric Blake3-9/+15
We've previously fixed several places where we failed to account for possible errors from bdrv_nb_sectors(). Fix another one by making bdrv_dirty_bitmap_truncate() take the new size from the caller instead of querying itself; then adjust the sole caller bdrv_truncate() to pass the size just determined by a successful resize, or to reuse the size given to the original truncate operation when refresh_total_sectors() was not able to confirm the actual size (the two sizes can potentially differ according to rounding constraints), thus avoiding sizing the bitmaps to -1. This also fixes a bug where not all failure paths in bdrv_truncate() would set errp. Note that bdrv_truncate() is still a bit awkward. We may want to revisit it later and clean up things to better guarantee that a resize attempt either fails cleanly up front, or cannot fail after guest-visible changes have been made (if temporary changes are made, then they need to be cleanly rolled back). But that is a task for another day; for now, the goal is the bare minimum fix to ensure that just bdrv_dirty_bitmap_truncate() cannot fail. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-06dirty-bitmap: Drop unused functionsEric Blake2-54/+0
We had several functions that no one is currently using, and which use sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions: bdrv_dirty_bitmap_get_meta bdrv_dirty_bitmap_get_meta_locked bdrv_dirty_bitmap_reset_meta bdrv_dirty_bitmap_meta_granularity 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>
2017-10-06qcow2: Ensure bitmap serialization is alignedEric Blake1-2/+5
When subdividing a bitmap serialization, the code in hbitmap.c enforces that start/count parameters are aligned (except that count can end early at end-of-bitmap). We exposed this required alignment through bdrv_dirty_bitmap_serialization_align(), but forgot to actually check that we comply with it. Fortunately, qcow2 is never dividing bitmap serialization smaller than one cluster (which is a minimum of 512 bytes); so we are always compliant with the serialization alignment (which insists that we partition at least 64 bits per chunk) because we are doing at least 4k bits per chunk. Still, it's safer to add an assertion (for the unlikely case that we'd ever support a cluster smaller than 512 bytes, or if the hbitmap implementation changes what it considers to be aligned), rather than leaving bdrv_dirty_bitmap_serialization_align() without a caller. 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>
2017-10-06hbitmap: Rename serialization_granularity to serialization_alignEric Blake4-14/+14
The only client of hbitmap_serialization_granularity() is dirty-bitmap's bdrv_dirty_bitmap_serialization_align(). Keeping the two names consistent is worthwhile, and the shorter name is more representative of what the function returns (the required alignment to be used for start/count of other serialization functions, where violating the alignment causes assertion failures). 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>
2017-10-06block: Make bdrv_img_create() size selection easier to readEric Blake1-1/+1
All callers of bdrv_img_create() pass in a size, or -1 to read the size from the backing file. We then set that size as the QemuOpt default, which means we will reuse that default rather than the final parameter to qemu_opt_get_size() several lines later. But it is rather confusing to read subsequent checks of 'size == -1' when it looks (without seeing the full context) like size defaults to 0; it also doesn't help that a size of 0 is valid (for some formats). Rework the logic to make things more legible. 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>