qemu/block
Eric Blake 8cb98a725e nbd/client: Simplify cookie vs. index computation
Our code relies on a sentinel cookie value of zero for deciding when a
packet has been handled, as well as relying on array indices between 0
and MAX_NBD_REQUESTS-1 for dereferencing purposes.  As long as we can
symmetrically convert between two forms, there is no reason to go with
the odd choice of using XOR with a random pointer, when we can instead
simplify the mappings with a mere offset of 1.

Using ((uint64_t)-1) as the sentinel instead of NULL such that the two
macros could be entirely eliminated might also be possible, but would
require a more careful audit to find places where we currently rely on
zero-initialization to be interpreted as the sentinel value, so I did
not pursue that course.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230608135653.2918540-7-eblake@redhat.com>
[eblake: enhance commit message]
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
2023-07-19 15:26:13 -05:00
..
export vhost-user: fully use new backend/frontend naming 2023-06-26 09:50:00 -04:00
monitor meson: Replace softmmu_ss -> system_ss 2023-06-20 10:01:30 +02:00
accounting.c block: add missed block_acct_setup with new block device init procedure 2022-09-30 18:42:34 +02:00
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: Mark BlockDriver callbacks for amend job GRAPH_RDLOCK 2023-05-10 14:16:54 +02:00
backup.c Block layer patches 2023-02-24 15:09:39 +00:00
blkdebug.c blkdebug: add missing coroutine_fn annotation 2023-04-25 13:17:28 +02:00
blkio.c block/blkio: fix module_block.py parsing 2023-07-04 17:28:25 +02:00
blklogwrites.c block: Mark bdrv_co_refresh_total_sectors() and callers GRAPH_RDLOCK 2023-02-23 19:49:33 +01:00
blkreplay.c block: Mark bdrv_co_refresh_total_sectors() and callers GRAPH_RDLOCK 2023-02-23 19:49:33 +01:00
blkverify.c block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCK 2023-05-10 14:16:54 +02:00
block-backend.c block: add blk_io_plug_call() API 2023-06-01 07:34:03 -04:00
block-copy.c block: Mark bdrv_co_pwrite_zeroes() and callers GRAPH_RDLOCK 2023-02-23 19:49:14 +01:00
block-gen.h block-coroutine-wrapper.py: support also basic return types 2022-12-15 16:07:43 +01:00
block-ram-registrar.c block: add BlockRAMRegistrar 2022-10-26 14:56:42 -04:00
bochs.c bochs: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:24 +02:00
cloop.c cloop: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:27 +02:00
commit.c blockjob: Adhere to rate limit even when reentered early 2023-05-19 19:12:12 +02:00
copy-before-write.c copy-before-write: Fix open with child in iothread 2023-05-30 17:29:35 +02:00
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: remove has_variable_length from filters 2023-04-11 16:38:56 +02:00
copy-on-read.h Clean up ill-advised or unusual header guards 2022-05-11 16:50:01 +02:00
coroutines.h nbd: Mark nbd_co_do_establish_connection() and callers GRAPH_RDLOCK 2023-05-10 14:16:53 +02:00
create.c block: Call .bdrv_co_create(_opts) unlocked 2023-05-19 19:12:12 +02:00
crypto.c block: Call .bdrv_co_create(_opts) unlocked 2023-05-19 19:12:12 +02:00
crypto.h nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
curl.c aio: remove aio_disable_external() API 2023-05-30 17:37:26 +02:00
dirty-bitmap.c block: Mark bdrv_*_dirty_bitmap() and callers GRAPH_RDLOCK 2023-02-23 19:49:32 +01:00
dmg-bz2.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
dmg-lzfse.c block/dmg: Ignore C99 prototype declaration mismatch from <lzfse.h> 2023-03-30 15:03:36 +02:00
dmg.c dmg: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:28 +02:00
dmg.h block/dmg: Declare a type definition for DMG uncompress function 2023-04-24 13:53:44 -04:00
file-posix.c file-posix: remove incorrect coroutine_fn calls 2023-06-28 09:46:14 +02:00
file-win32.c thread-pool: avoid passing the pool parameter every time 2023-04-25 13:17:28 +02:00
filter-compress.c block: remove has_variable_length from filters 2023-04-11 16:38:56 +02:00
gluster.c cutils: Adjust signature of parse_uint[_full] 2023-06-02 12:27:19 -05:00
graph-lock.c Revert "graph-lock: Disable locking for now" 2023-06-28 08:46:26 +02:00
io_uring.c block/io_uring: convert to blk_io_plug_call() API 2023-06-01 07:34:03 -04:00
io.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
iscsi-opts.c modules: add block module annotations 2021-07-09 18:20:27 +02:00
iscsi.c aio: remove aio_disable_external() API 2023-05-30 17:37:26 +02:00
linux-aio.c block/linux-aio: convert to blk_io_plug_call() API 2023-06-01 07:34:03 -04:00
meson.build meson: Replace softmmu_ss -> system_ss 2023-06-20 10:01:30 +02:00
mirror.c mirror: Hold main AioContext lock for calling bdrv_open_backing_file() 2023-05-30 17:21:23 +02:00
nbd.c nbd/client: Simplify cookie vs. index computation 2023-07-19 15:26:13 -05:00
nfs.c cutils: Adjust signature of parse_uint[_full] 2023-06-02 12:27:19 -05:00
null.c block: Convert bdrv_get_allocated_file_size() to co_wrapper 2023-02-01 16:52:32 +01:00
nvme.c block/nvme: invoke blk_io_plug_call() outside q->lock 2023-07-17 09:17:41 -04:00
parallels-ext.c include/block: Untangle inclusion loops 2023-01-20 07:24:28 +01:00
parallels.c block: use bdrv_co_getlength in coroutine context 2023-06-28 09:46:33 +02:00
parallels.h parallels: support bitmap extension for read-only mode 2021-03-08 14:56:55 +01:00
plug.c block: add blk_io_plug_call() API 2023-06-01 07:34:03 -04:00
preallocate.c block: remove has_variable_length from filters 2023-04-11 16:38:56 +02:00
progress_meter.c coroutine: Clean up superfluous inclusion of qemu/lockable.h 2023-01-19 10:18:28 +01:00
qapi-sysemu.c block: Take main AioContext lock when calling bdrv_open() 2023-05-30 17:21:23 +02:00
qapi.c block: add accounting for zone append operation 2023-05-15 08:18:10 -04:00
qcow2-bitmap.c qcow2: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:32 +02:00
qcow2-cache.c include/block: Untangle inclusion loops 2023-01-20 07:24:28 +01:00
qcow2-cluster.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
qcow2-refcount.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
qcow2-snapshot.c qcow2: mark various functions as coroutine_fn and GRAPH_RDLOCK 2023-04-25 13:17:28 +02:00
qcow2-threads.c thread-pool: avoid passing the pool parameter every time 2023-04-25 13:17:28 +02:00
qcow2.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
qcow2.h qcow2: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:32 +02:00
qcow.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
qed-check.c qed: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:20 +02:00
qed-cluster.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-l2-cache.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
qed-table.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
qed.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
qed.h block: Mark public read/write functions GRAPH_RDLOCK 2023-02-23 19:49:17 +01:00
quorum.c block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCK 2023-05-10 14:16:54 +02:00
raw-format.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
rbd.c block/rbd: Add support for layered encryption 2023-02-23 19:49:35 +01:00
replication.c block: remove has_variable_length from filters 2023-04-11 16:38:56 +02:00
reqlist.c block/reqlist: add reqlist_wait_all() 2022-03-07 09:33:30 +01:00
snapshot-access.c block: Mark preadv_snapshot/snapshot_block_status GRAPH_RDLOCK 2023-02-23 19:49:21 +01:00
snapshot.c block/snapshot: drop indirection around bdrv_snapshot_fallback_ptr 2022-10-27 20:14:11 +02:00
ssh.c aio: remove aio_disable_external() API 2023-05-30 17:37:26 +02:00
stream.c blockjob: Adhere to rate limit even when reentered early 2023-05-19 19:12:12 +02:00
throttle-groups.c block/throttle-groups: throttle_group_co_io_limits_intercept(): 64bit bytes 2021-02-03 08:14:00 -06:00
throttle.c block: Mark bdrv_co_refresh_total_sectors() and callers GRAPH_RDLOCK 2023-02-23 19:49:33 +01:00
trace-events block/io_uring: convert to blk_io_plug_call() API 2023-06-01 07:34:03 -04:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
vdi.c block: Call .bdrv_co_create(_opts) unlocked 2023-05-19 19:12:12 +02:00
vhdx-endian.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
vhdx-log.c vhdx: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:30 +02:00
vhdx.c vhdx: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:30 +02:00
vhdx.h vhdx: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:30 +02:00
vmdk.c block: use bdrv_co_debug_event in coroutine context 2023-06-28 09:46:34 +02:00
vpc.c vpc: mark more functions as coroutine_fns and GRAPH_RDLOCK 2023-06-28 09:46:23 +02:00
vvfat.c vvfat: mark various functions as coroutine_fn 2023-04-25 13:17:28 +02:00
win32-aio.c aio: remove aio_disable_external() API 2023-05-30 17:37:26 +02:00
write-threshold.c include/block: Untangle inclusion loops 2023-01-20 07:24:28 +01:00