qemu-e2k/block
Hanna Reitz a8c07ec287 qcow2: Improve refcount structure rebuilding
When rebuilding the refcount structures (when qemu-img check -r found
errors with refcount = 0, but reference count > 0), the new refcount
table defaults to being put at the image file end[1].  There is no good
reason for that except that it means we will not have to rewrite any
refblocks we already wrote to disk.

Changing the code to rewrite those refblocks is not too difficult,
though, so let us do that.  That is beneficial for images on block
devices, where we cannot really write beyond the end of the image file.

Use this opportunity to add extensive comments to the code, and refactor
it a bit, getting rid of the backwards-jumping goto.

[1] Unless there is something allocated in the area pointed to by the
    last refblock, so we have to write that refblock.  In that case, we
    try to put the reftable in there.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1519071
Closes: https://gitlab.com/qemu-project/qemu/-/issues/941
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220405134652.19278-2-hreitz@redhat.com>
2022-04-20 10:14:28 +02:00
..
export osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
monitor block/dirty-bitmap: bdrv_merge_dirty_bitmap(): add return value 2022-03-07 09:33:30 +01:00
accounting.c
aio_task.c block/aio_task: assert max_busy_tasks is greater than 0 2021-10-05 18:56:41 +02:00
amend.c block/amend: Keep strong reference to BDS 2022-03-04 18:18:26 +01:00
backup.c assertions for block_int global state API 2022-03-04 18:18:25 +01:00
blkdebug.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
blklogwrites.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
blkreplay.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
blkverify.c Replace GCC_FMT_ATTR with G_GNUC_PRINTF 2022-03-22 14:40:51 +04:00
block-backend.c block/coroutines: I/O and "I/O or GS" API 2022-03-04 18:18:25 +01:00
block-copy.c target-arm queue: 2022-03-08 15:26:10 +00:00
block-gen.h
bochs.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
cloop.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
commit.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
copy-before-write.c block: copy-before-write: realize snapshot-access API 2022-03-07 09:33:31 +01:00
copy-before-write.h block/copy-before-write.h: global state API + assertions 2022-03-04 18:18:25 +01:00
copy-on-read.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
copy-on-read.h
coroutines.h block/coroutines: I/O and "I/O or GS" API 2022-03-04 18:18:25 +01:00
create.c block_int-common.h: assertions in the callers of BlockDriver function pointers 2022-03-04 18:18:25 +01:00
crypto.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
crypto.h
curl.c block/curl.c: Check error return from curl_easy_setopt() 2022-03-07 09:19:20 +01:00
dirty-bitmap.c block/dirty-bitmap: introduce bdrv_dirty_bitmap_status() 2022-03-07 09:33:30 +01:00
dmg-bz2.c
dmg-lzfse.c
dmg.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
dmg.h
file-posix.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
file-win32.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
filter-compress.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
gluster.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
io_uring.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
io.c Replace qemu_real_host_page variables with inlined functions 2022-04-06 10:50:38 +02:00
iscsi-opts.c modules: add block module annotations 2021-07-09 18:20:27 +02:00
iscsi.c include: move qemu_get_vm_name() to sysemu.h 2022-04-06 14:31:43 +02:00
linux-aio.c aio-posix: split poll check from ready handler 2022-01-12 17:09:39 +00:00
meson.build block: introduce snapshot-access block driver 2022-03-07 09:33:31 +01:00
mirror.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
nbd.c block/nbd.c: Fixed IO request coroutine not being wakeup when kill NBD server 2022-03-21 15:21:09 -05:00
nfs.c aio-posix: split poll check from ready handler 2022-01-12 17:09:39 +00:00
null.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
nvme.c Replace qemu_real_host_page variables with inlined functions 2022-04-06 10:50:38 +02:00
parallels-ext.c block: Fix misleading hexadecimal format 2022-03-24 10:38:42 +00:00
parallels.c Replace qemu_real_host_page variables with inlined functions 2022-04-06 10:50:38 +02:00
parallels.h
preallocate.c block: fix preallocate filter: don't do unaligned preallocate requests 2022-03-07 09:19:20 +01:00
progress_meter.c progressmeter: protect with a mutex 2021-06-25 14:24:24 +03:00
qapi-sysemu.c
qapi.c block: use GDateTime for formatting timestamp when dumping snapshot info 2021-06-14 13:28:50 +01:00
qcow2-bitmap.c
qcow2-cache.c Replace qemu_real_host_page variables with inlined functions 2022-04-06 10:50:38 +02:00
qcow2-cluster.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qcow2-refcount.c qcow2: Improve refcount structure rebuilding 2022-04-20 10:14:28 +02:00
qcow2-snapshot.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qcow2-threads.c
qcow2.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qcow2.h Replace GCC_FMT_ATTR with G_GNUC_PRINTF 2022-03-22 14:40:51 +04:00
qcow.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qed-check.c
qed-cluster.c
qed-l2-cache.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qed-table.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qed.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qed.h
quorum.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
raw-format.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
rbd.c block/rbd: fix write zeroes with growing images 2022-03-22 09:40:54 +01:00
replication.c job: @force parameter for job_cancel_sync() 2021-10-07 10:42:09 +02:00
reqlist.c block/reqlist: add reqlist_wait_all() 2022-03-07 09:33:30 +01:00
snapshot-access.c block: introduce snapshot-access block driver 2022-03-07 09:33:31 +01:00
snapshot.c include/block/snapshot: global state API + assertions 2022-03-04 18:18:25 +01:00
ssh.c Replace GCC_FMT_ATTR with G_GNUC_PRINTF 2022-03-22 14:40:51 +04:00
stream.c block/stream: Drain subtree around graph change 2022-03-29 16:30:55 +02:00
throttle-groups.c
throttle.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
trace-events block/nvme: Display CQ/SQ pointer in nvme_free_queue_pair() 2021-11-02 15:49:12 +01:00
trace.h
vdi.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
vhdx-endian.c
vhdx-log.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
vhdx.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
vhdx.h
vmdk.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
vpc.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
vvfat.c vvfat: Fix vvfat_write() for writes before the root directory 2022-01-14 12:03:16 +01:00
win32-aio.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
write-threshold.c write-threshold: deal with includes 2021-05-14 16:14:10 +02:00