xemu/block
Fam Zheng 2996ffad3a file-posix: Skip effectiveless OFD lock operations
If we know we've already locked the bytes, don't do it again; similarly
don't unlock a byte if we haven't locked it. This doesn't change the
behavior, but fixes a corner case explained below.

Libvirt had an error handling bug that an image can get its (ownership,
file mode, SELinux) permissions changed (RHBZ 1584982) by mistake behind
QEMU. Specifically, an image in use by Libvirt VM has:

    $ ls -lhZ b.img
    -rw-r--r--. qemu qemu system_u:object_r:svirt_image_t:s0:c600,c690 b.img

Trying to attach it a second time won't work because of image locking.
And after the error, it becomes:

    $ ls -lhZ b.img
    -rw-r--r--. root root system_u:object_r:virt_image_t:s0 b.img

Then, we won't be able to do OFD lock operations with the existing fd.
In other words, the code such as in blk_detach_dev:

    blk_set_perm(blk, 0, BLK_PERM_ALL, &error_abort);

can abort() QEMU, out of environmental changes.

This patch is an easy fix to this and the change is regardlessly
reasonable, so do it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-11-12 17:46:57 +01:00
..
accounting.c block/accounting: introduce latency histogram 2018-03-19 14:58:37 -05:00
backup.c block/backup: make function variables consistently named 2018-08-31 16:28:33 +02:00
blkdebug.c qstring: Move qstring_from_substr()'s @end one to the right 2018-07-28 09:09:58 +02:00
blklogwrites.c block: Use BdrvChild to discard 2018-07-10 16:01:52 +02:00
blkreplay.c trivial: Make bios files and source files non-executable 2018-09-25 17:26:18 +02:00
blkverify.c qstring: Move qstring_from_substr()'s @end one to the right 2018-07-28 09:09:58 +02:00
block-backend.c block: change some function return type to bool 2018-11-05 15:09:54 +01:00
bochs.c block: Require auto-read-only for existing fallbacks 2018-11-05 15:09:55 +01:00
cloop.c block: Require auto-read-only for existing fallbacks 2018-11-05 15:09:55 +01:00
commit.c block/commit: refactor commit to use job callbacks 2018-09-25 15:31:15 +02:00
copy-on-read.c block: drop empty .bdrv_close handlers 2018-08-15 12:50:39 +02:00
create.c jobs: utilize job_exit shim 2018-08-31 16:28:33 +02:00
crypto.c luks: Allow share-rw=on 2018-08-15 12:50:39 +02:00
crypto.h block/crypto: Simplify block_crypto_{open,create}_opts_init() 2018-06-29 14:20:56 +02:00
curl.c curl: Support auto-read-only option 2018-11-05 15:09:55 +01:00
dirty-bitmap.c dirty-bitmaps: clean-up bitmaps loading and migration logic 2018-10-29 16:23:17 -04:00
dmg-bz2.c dmg: Move libbz2 code to dmg-bz2.so 2016-10-07 14:14:06 +02:00
dmg.c block: Require auto-read-only for existing fallbacks 2018-11-05 15:09:55 +01:00
dmg.h block: remove "qemu/osdep.h" from header file 2017-12-18 17:07:02 +03:00
file-posix.c file-posix: Skip effectiveless OFD lock operations 2018-11-12 17:46:57 +01:00
file-win32.c block: Prefix file driver trace points with "file_" 2018-07-10 16:01:51 +02:00
gluster.c gluster: Support auto-read-only option 2018-11-05 15:09:55 +01:00
io.c block: Use a single global AioWait 2018-09-25 15:50:15 +02:00
iscsi-opts.c Move include qemu/option.h from qemu-common.h to actual users 2018-02-09 13:52:16 +01:00
iscsi.c iscsi: Support auto-read-only option 2018-11-05 15:09:55 +01:00
linux-aio.c block/linux-aio: acquire AioContext before qemu_laio_process_completions 2018-09-25 15:50:15 +02:00
Makefile.objs block: Add blklogwrites 2018-07-05 10:29:19 +02:00
mirror.c block/mirror: conservative mirror_exit refactor 2018-09-25 15:31:15 +02:00
nbd-client.c nbd: Support auto-read-only option 2018-11-05 15:09:55 +01:00
nbd-client.h nbd/client: Add x-dirty-bitmap to query bitmap from server 2018-07-02 15:27:38 -05:00
nbd.c qstring: Move qstring_from_substr()'s @end one to the right 2018-07-28 09:09:58 +02:00
nfs.c block: Convert .bdrv_truncate callback to coroutine_fn 2018-06-29 14:20:56 +02:00
null.c block: drop empty .bdrv_close handlers 2018-08-15 12:50:39 +02:00
nvme.c nvme: correct locking around completion 2018-10-12 09:46:14 +08:00
parallels.c parallels: Switch to byte-based calls 2018-06-29 14:20:56 +02:00
parallels.h Clean up includes 2018-02-09 05:05:11 +01:00
qapi.c block/qapi: Fix memory leak in qmp_query_blockstats() 2018-08-15 12:50:39 +02:00
qcow2-bitmap.c block/qcow2-bitmap: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
qcow2-cache.c qcow2: Allow configuring the L2 slice size 2018-02-13 17:00:00 +01:00
qcow2-cluster.c qcow2: Free allocated clusters on write error 2018-06-29 14:20:56 +02:00
qcow2-refcount.c Block layer patches: 2018-07-10 17:28:29 +01:00
qcow2-snapshot.c block: use local path for local headers 2018-05-31 04:16:06 +03:00
qcow2.c qcow2: Get the request alignment for encrypted images from QCryptoBlock 2018-11-05 15:09:54 +01:00
qcow2.h bloc/qcow2: drop dirty_bitmaps_loaded state variable 2018-10-29 16:23:15 -04:00
qcow.c block/qcow: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
qed-check.c block: convert bdrv_check callback to coroutine_fn 2018-03-09 15:17:47 +01:00
qed-cluster.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-l2-cache.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-table.c block: convert bdrv_check callback to coroutine_fn 2018-03-09 15:17:47 +01:00
qed.c error: Fix use of error_prepend() with &error_fatal, &error_abort 2018-10-19 14:51:34 +02:00
qed.h qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
quorum.c quorum: Forbid adding children in blkverify mode 2018-11-05 15:09:54 +01:00
raw-format.c block: drop empty .bdrv_close handlers 2018-08-15 12:50:39 +02:00
rbd.c block: Require auto-read-only for existing fallbacks 2018-11-05 15:09:55 +01:00
replication.c replication: Switch to byte-based calls 2018-06-29 14:20:56 +02:00
sheepdog.c block: Use warn_report() & friends to report warnings 2018-10-19 14:51:34 +02:00
snapshot.c block: make .bdrv_close optional 2018-08-15 12:50:39 +02:00
ssh.c block: Convert .bdrv_truncate callback to coroutine_fn 2018-06-29 14:20:56 +02:00
stream.c block/stream: refactor stream to use job callbacks 2018-09-25 15:31:15 +02:00
throttle-groups.c throttle-groups: Don't allow timers without throttled requests 2018-08-15 12:50:39 +02:00
throttle.c block: Use BdrvChild to discard 2018-07-10 16:01:52 +02:00
trace-events block: Add copy offloading trace points 2018-07-10 16:01:52 +02:00
vdi.c vdi: Use a literal number of bytes for DEFAULT_CLUSTER_SIZE 2018-11-05 15:28:48 +01:00
vhdx-endian.c block/vhdx: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
vhdx-log.c block/vhdx: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
vhdx.c block/vhdx: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
vhdx.h block/vhdx: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
vmdk.c vmdk: align end of file to a sector boundary 2018-09-26 10:47:18 +08:00
vpc.c vpc: Don't leak opts in vpc_open() 2018-11-05 15:09:54 +01:00
vvfat.c block: Require auto-read-only for existing fallbacks 2018-11-05 15:09:55 +01:00
vxhs.c block: Add block-specific QDict header 2018-06-15 14:49:44 +02:00
win32-aio.c file-win32: Switch to byte-based callbacks 2018-05-15 16:11:41 +02:00
write-threshold.c qapi: Drop qapi_event_send_FOO()'s Error ** argument 2018-08-28 18:21:38 +02:00