]>
Commit | Line | Data |
---|---|---|
27199bd7 FE |
1 | From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 |
2 | From: Fabian Ebner <f.ebner@proxmox.com> | |
3 | Date: Wed, 2 Mar 2022 08:35:05 +0100 | |
4 | Subject: [PATCH] block/backup: move bcs bitmap initialization to job creation | |
5 | ||
6 | For backing up the state of multiple disks from the same time, a job | |
7 | for each disk has to be created. It's convenient if the jobs don't | |
8 | have to be started at the same time and if operation of the VM can be | |
9 | resumed after job creation. This would lead to a window between job | |
10 | creation and running the job, where writes can happen. But no writes | |
11 | should happen between setting up the copy-before-write filter and | |
12 | setting up the block copy state bitmap, because then new writes would | |
13 | just pass through. | |
14 | ||
15 | Commit 06e0a9c16405c0a4c1eca33cf286cc04c42066a2 moved initalization of | |
16 | the bitmap to setting up the copy-before-write filter when sync_mode | |
17 | is not MIRROR_SYNC_MODE_BITMAP. Ensure that the bitmap is initialized | |
18 | upon job creation for the remaining case too, by moving the | |
19 | backup_init_bcs_bitmap call to backup_job_create. | |
20 | ||
21 | Signed-off-by: Fabian Ebner <f.ebner@proxmox.com> | |
22 | --- | |
23 | block/backup.c | 8 ++++---- | |
24 | 1 file changed, 4 insertions(+), 4 deletions(-) | |
25 | ||
26 | diff --git a/block/backup.c b/block/backup.c | |
27 | index 21d5983779..47e218857d 100644 | |
28 | --- a/block/backup.c | |
29 | +++ b/block/backup.c | |
30 | @@ -239,8 +239,8 @@ static void backup_init_bcs_bitmap(BackupBlockJob *job) | |
31 | assert(ret); | |
32 | } else if (job->sync_mode == MIRROR_SYNC_MODE_TOP) { | |
33 | /* | |
34 | - * We can't hog the coroutine to initialize this thoroughly. | |
35 | - * Set a flag and resume work when we are able to yield safely. | |
36 | + * Initialization is costly here. Simply set a flag and let the | |
37 | + * backup_run coroutine resume work once it can yield safely. | |
38 | */ | |
39 | block_copy_set_skip_unallocated(job->bcs, true); | |
40 | } | |
41 | @@ -254,8 +254,6 @@ static int coroutine_fn backup_run(Job *job, Error **errp) | |
42 | BackupBlockJob *s = container_of(job, BackupBlockJob, common.job); | |
43 | int ret; | |
44 | ||
45 | - backup_init_bcs_bitmap(s); | |
46 | - | |
47 | if (s->sync_mode == MIRROR_SYNC_MODE_TOP) { | |
48 | int64_t offset = 0; | |
49 | int64_t count; | |
50 | @@ -493,6 +491,8 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, | |
51 | block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL, | |
52 | &error_abort); | |
53 | ||
54 | + backup_init_bcs_bitmap(job); | |
55 | + | |
56 | return &job->common; | |
57 | ||
58 | error: |