Skip to content

Commit

Permalink
block: Add blk_new_with_bs() helper
Browse files Browse the repository at this point in the history 
There are several callers that need to create a new block backend from
an existing BDS; make the task slightly easier with a common helper
routine.

Suggested-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200424190903.522087-2-eblake@redhat.com>
[mreitz: Set @ret only in error paths, see
 https://lists.nongnu.org/archive/html/qemu-block/2020-04/msg01216.html]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200428192648.749066-2-eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
  • Loading branch information
@ebblake @XanClic
ebblake authored and XanClic committed May 5, 2020
1 parent 52ea799 commit a3aeeab
Show file tree
Hide file tree
Showing 14 changed files with 75 additions and 59 deletions.
23 changes: 23 additions & 0 deletions block/block-backend.c
View file
Expand Up @@ -355,6 +355,29 @@ BlockBackend *blk_new(AioContext *ctx, uint64_t perm, uint64_t shared_perm)
return blk;
}

/*
* Create a new BlockBackend connected to an existing BlockDriverState.
*
* @perm is a bitmasks of BLK_PERM_* constants which describes the
* permissions to request for @bs that is attached to this
* BlockBackend. @shared_perm is a bitmask which describes which
* permissions may be granted to other users of the attached node.
* Both sets of permissions can be changed later using blk_set_perm().
*
* Return the new BlockBackend on success, null on failure.
*/
BlockBackend *blk_new_with_bs(BlockDriverState *bs, uint64_t perm,
uint64_t shared_perm, Error **errp)
{
BlockBackend *blk = blk_new(bdrv_get_aio_context(bs), perm, shared_perm);

if (blk_insert_bs(blk, bs, errp) < 0) {
blk_unref(blk);
return NULL;
}
return blk;
}

/*
* Creates a new BlockBackend, opens a new BlockDriverState, and connects both.
* The new BlockBackend is in the main AioContext.
Expand Down
9 changes: 4 additions & 5 deletions block/crypto.c
View file
Expand Up @@ -261,11 +261,10 @@ static int block_crypto_co_create_generic(BlockDriverState *bs,
QCryptoBlock *crypto = NULL;
struct BlockCryptoCreateData data;

blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);

ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
ret = -EPERM;
goto cleanup;
}

Expand Down
8 changes: 4 additions & 4 deletions block/parallels.c
View file
Expand Up @@ -559,10 +559,10 @@ static int coroutine_fn parallels_co_create(BlockdevCreateOptions* opts,
return -EIO;
}

blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
ret = -EPERM;
goto out;
}
blk_set_allow_write_beyond_eof(blk, true);
Expand Down
8 changes: 4 additions & 4 deletions block/qcow.c
View file
Expand Up @@ -849,10 +849,10 @@ static int coroutine_fn qcow_co_create(BlockdevCreateOptions *opts,
return -EIO;
}

qcow_blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(qcow_blk, bs, errp);
if (ret < 0) {
qcow_blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL, errp);
if (!qcow_blk) {
ret = -EPERM;
goto exit;
}
blk_set_allow_write_beyond_eof(qcow_blk, true);
Expand Down
18 changes: 8 additions & 10 deletions block/qcow2.c
View file
Expand Up @@ -3405,10 +3405,10 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
}

/* Create BlockBackend to write to the image */
blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
ret = -EPERM;
goto out;
}
blk_set_allow_write_beyond_eof(blk, true);
Expand Down Expand Up @@ -5412,12 +5412,10 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,
}

if (new_size) {
BlockBackend *blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk_unref(blk);
return ret;
BlockBackend *blk = blk_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
return -EPERM;
}

/*
Expand Down
8 changes: 4 additions & 4 deletions block/qed.c
View file
Expand Up @@ -651,10 +651,10 @@ static int coroutine_fn bdrv_qed_co_create(BlockdevCreateOptions *opts,
return -EIO;
}

blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
ret = -EPERM;
goto out;
}
blk_set_allow_write_beyond_eof(blk, true);
Expand Down
10 changes: 5 additions & 5 deletions block/sheepdog.c
View file
Expand Up @@ -1803,12 +1803,12 @@ static int sd_prealloc(BlockDriverState *bs, int64_t old_size, int64_t new_size,
void *buf = NULL;
int ret;

blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL);
blk = blk_new_with_bs(bs,
BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL, errp);

ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
if (!blk) {
ret = -EPERM;
goto out_with_err_set;
}

Expand Down
8 changes: 4 additions & 4 deletions block/vdi.c
View file
Expand Up @@ -804,10 +804,10 @@ static int coroutine_fn vdi_co_do_create(BlockdevCreateOptions *create_options,
goto exit;
}

blk = blk_new(bdrv_get_aio_context(bs_file),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs_file, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs_file, BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL, errp);
if (!blk) {
ret = -EPERM;
goto exit;
}

Expand Down
8 changes: 4 additions & 4 deletions block/vhdx.c
View file
Expand Up @@ -1984,10 +1984,10 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
return -EIO;
}

blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
ret = -EPERM;
goto delete_and_exit;
}
blk_set_allow_write_beyond_eof(blk, true);
Expand Down
9 changes: 4 additions & 5 deletions block/vmdk.c
View file
Expand Up @@ -2717,11 +2717,10 @@ static BlockBackend *vmdk_co_create_cb(int64_t size, int idx,
if (!bs) {
return NULL;
}
blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL);
if (blk_insert_bs(blk, bs, errp)) {
bdrv_unref(bs);
blk = blk_new_with_bs(bs,
BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL, errp);
if (!blk) {
return NULL;
}
blk_set_allow_write_beyond_eof(blk, true);
Expand Down
8 changes: 4 additions & 4 deletions block/vpc.c
View file
Expand Up @@ -1012,10 +1012,10 @@ static int coroutine_fn vpc_co_create(BlockdevCreateOptions *opts,
return -EIO;
}

blk = blk_new(bdrv_get_aio_context(bs),
BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
errp);
if (!blk) {
ret = -EPERM;
goto out;
}
blk_set_allow_write_beyond_eof(blk, true);
Expand Down
8 changes: 3 additions & 5 deletions blockdev.c
View file
Expand Up @@ -2711,7 +2711,6 @@ void qmp_block_resize(bool has_device, const char *device,
BlockBackend *blk = NULL;
BlockDriverState *bs;
AioContext *aio_context;
int ret;

bs = bdrv_lookup_bs(has_device ? device : NULL,
has_node_name ? node_name : NULL,
Expand All @@ -2734,14 +2733,13 @@ void qmp_block_resize(bool has_device, const char *device,
goto out;
}

blk = blk_new(bdrv_get_aio_context(bs), BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk = blk_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
if (!blk) {
goto out;
}

bdrv_drained_begin(bs);
ret = blk_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
blk_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
bdrv_drained_end(bs);

out:
Expand Down
7 changes: 2 additions & 5 deletions blockjob.c
View file
Expand Up @@ -397,16 +397,13 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
{
BlockBackend *blk;
BlockJob *job;
int ret;

if (job_id == NULL && !(flags & JOB_INTERNAL)) {
job_id = bdrv_get_device_name(bs);
}

blk = blk_new(bdrv_get_aio_context(bs), perm, shared_perm);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk_unref(blk);
blk = blk_new_with_bs(bs, perm, shared_perm, errp);
if (!blk) {
return NULL;
}

Expand Down
2 changes: 2 additions & 0 deletions include/sysemu/block-backend.h
View file
Expand Up @@ -77,6 +77,8 @@ typedef struct BlockBackendPublic {
} BlockBackendPublic;

BlockBackend *blk_new(AioContext *ctx, uint64_t perm, uint64_t shared_perm);
BlockBackend *blk_new_with_bs(BlockDriverState *bs, uint64_t perm,
uint64_t shared_perm, Error **errp);
BlockBackend *blk_new_open(const char *filename, const char *reference,
QDict *options, int flags, Error **errp);
int blk_get_refcnt(BlockBackend *blk);
Expand Down

0 comments on commit a3aeeab

Please sign in to comment.