block: Add BlockBackend.ctx

This adds a new parameter to blk_new() which requires its callers to
declare from which AioContext this BlockBackend is going to be used (or
the locks of which AioContext need to be taken anyway).

The given context is only stored and kept up to date when changing
AioContexts. Actually applying the stored AioContext to the root node
is saved for another commit.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2019-04-25 14:25:10 +02:00
parent 97896a4887
commit d861ab3acf
33 changed files with 102 additions and 64 deletions

View file

@ -338,7 +338,8 @@ void commit_start(const char *job_id, BlockDriverState *bs,
goto fail;
}
s->base = blk_new(BLK_PERM_CONSISTENT_READ
s->base = blk_new(s->common.job.aio_context,
BLK_PERM_CONSISTENT_READ
| BLK_PERM_WRITE
| BLK_PERM_RESIZE,
BLK_PERM_CONSISTENT_READ
@ -351,7 +352,7 @@ void commit_start(const char *job_id, BlockDriverState *bs,
s->base_bs = base;
/* Required permissions are already taken with block_job_add_bdrv() */
s->top = blk_new(0, BLK_PERM_ALL);
s->top = blk_new(s->common.job.aio_context, 0, BLK_PERM_ALL);
ret = blk_insert_bs(s->top, top, errp);
if (ret < 0) {
goto fail;
@ -395,6 +396,7 @@ int bdrv_commit(BlockDriverState *bs)
BlockDriverState *backing_file_bs = NULL;
BlockDriverState *commit_top_bs = NULL;
BlockDriver *drv = bs->drv;
AioContext *ctx;
int64_t offset, length, backing_length;
int ro;
int64_t n;
@ -422,8 +424,9 @@ int bdrv_commit(BlockDriverState *bs)
}
}
src = blk_new(BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL);
backing = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ctx = bdrv_get_aio_context(bs);
src = blk_new(ctx, BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL);
backing = blk_new(ctx, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(src, bs, &local_err);
if (ret < 0) {