blockjob: Add permissions to block_job_add_bdrv()

Block jobs don't actually do I/O through the the reference they create
with block_job_add_bdrv(), but they might want to use the permisssion
system to express what the block job does to intermediate nodes. This
adds permissions to block_job_add_bdrv() to provide the means to request
permissions.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
This commit is contained in:
Kevin Wolf 2017-01-17 11:56:42 +01:00
parent 26de9438c1
commit 76d554e20b
6 changed files with 53 additions and 13 deletions

View file

@ -657,7 +657,9 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
job->cluster_size = MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size);
}
block_job_add_bdrv(&job->common, target);
/* FIXME Use real permissions */
block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
&error_abort);
job->common.len = len;
block_job_txn_add_job(txn, &job->common);

View file

@ -267,13 +267,17 @@ void commit_start(const char *job_id, BlockDriverState *bs,
* disappear from the chain after this operation. */
assert(bdrv_chain_contains(top, base));
for (iter = top; iter != backing_bs(base); iter = backing_bs(iter)) {
block_job_add_bdrv(&s->common, iter);
/* FIXME Use real permissions */
block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
BLK_PERM_ALL, &error_abort);
}
/* overlay_bs must be blocked because it needs to be modified to
* update the backing image string, but if it's the root node then
* don't block it again */
if (bs != overlay_bs) {
block_job_add_bdrv(&s->common, overlay_bs);
/* FIXME Use real permissions */
block_job_add_bdrv(&s->common, "overlay of top", overlay_bs, 0,
BLK_PERM_ALL, &error_abort);
}
/* FIXME Use real permissions */

View file

@ -1052,13 +1052,18 @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs,
return;
}
block_job_add_bdrv(&s->common, target);
/* FIXME Use real permissions */
block_job_add_bdrv(&s->common, "target", target, 0, BLK_PERM_ALL,
&error_abort);
/* In commit_active_start() all intermediate nodes disappear, so
* any jobs in them must be blocked */
if (bdrv_chain_contains(bs, target)) {
BlockDriverState *iter;
for (iter = backing_bs(bs); iter != target; iter = backing_bs(iter)) {
block_job_add_bdrv(&s->common, iter);
/* FIXME Use real permissions */
block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
BLK_PERM_ALL, &error_abort);
}
}

View file

@ -248,7 +248,9 @@ void stream_start(const char *job_id, BlockDriverState *bs,
/* Block all intermediate nodes between bs and base, because they
* will disappear from the chain after this operation */
for (iter = backing_bs(bs); iter && iter != base; iter = backing_bs(iter)) {
block_job_add_bdrv(&s->common, iter);
/* FIXME Use real permissions */
block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
BLK_PERM_ALL, &error_abort);
}
s->base = base;

View file

@ -55,6 +55,19 @@ struct BlockJobTxn {
static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs);
static char *child_job_get_parent_desc(BdrvChild *c)
{
BlockJob *job = c->opaque;
return g_strdup_printf("%s job '%s'",
BlockJobType_lookup[job->driver->job_type],
job->id);
}
static const BdrvChildRole child_job = {
.get_parent_desc = child_job_get_parent_desc,
.stay_at_node = true,
};
BlockJob *block_job_next(BlockJob *job)
{
if (!job) {
@ -115,11 +128,22 @@ static void block_job_detach_aio_context(void *opaque)
block_job_unref(job);
}
void block_job_add_bdrv(BlockJob *job, BlockDriverState *bs)
int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs,
uint64_t perm, uint64_t shared_perm, Error **errp)
{
job->nodes = g_slist_prepend(job->nodes, bs);
BdrvChild *c;
c = bdrv_root_attach_child(bs, name, &child_job, perm, shared_perm,
job, errp);
if (c == NULL) {
return -EPERM;
}
job->nodes = g_slist_prepend(job->nodes, c);
bdrv_ref(bs);
bdrv_op_block_all(bs, job->blocker);
return 0;
}
void *block_job_create(const char *job_id, const BlockJobDriver *driver,
@ -171,7 +195,7 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
job = g_malloc0(driver->instance_size);
error_setg(&job->blocker, "block device is in use by block job: %s",
BlockJobType_lookup[driver->job_type]);
block_job_add_bdrv(job, bs);
block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
job->driver = driver;
@ -238,9 +262,9 @@ void block_job_unref(BlockJob *job)
BlockDriverState *bs = blk_bs(job->blk);
bs->job = NULL;
for (l = job->nodes; l; l = l->next) {
bs = l->data;
bdrv_op_unblock_all(bs, job->blocker);
bdrv_unref(bs);
BdrvChild *c = l->data;
bdrv_op_unblock_all(c->bs, job->blocker);
bdrv_root_unref_child(c);
}
g_slist_free(job->nodes);
blk_remove_aio_context_notifier(job->blk,

View file

@ -169,13 +169,16 @@ BlockJob *block_job_get(const char *id);
/**
* block_job_add_bdrv:
* @job: A block job
* @name: The name to assign to the new BdrvChild
* @bs: A BlockDriverState that is involved in @job
* @perm, @shared_perm: Permissions to request on the node
*
* Add @bs to the list of BlockDriverState that are involved in
* @job. This means that all operations will be blocked on @bs while
* @job exists.
*/
void block_job_add_bdrv(BlockJob *job, BlockDriverState *bs);
int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs,
uint64_t perm, uint64_t shared_perm, Error **errp);
/**
* block_job_set_speed: