Re: [PATCH v10 8/9] block: remove unused backing-file name parameter

2020-10-07 Thread Andrey Shinkevich



On 07.10.2020 13:21, Vladimir Sementsov-Ogievskiy wrote:

29.09.2020 15:38, Andrey Shinkevich wrote:

The block stream QMP parameter backing-file is in use no more. It
designates a backing file name to set in QCOW2 image header after the
block stream job finished. The base file name is used instead.

Signed-off-by: Andrey Shinkevich 


We can't just remove it without a deprecation period of three releases.


It has not been in use for a long. It's time.



So actually, in a previous patch, we should implement new behavior for
automatic backing-file detection if this parameter is unspecified. Amd
keep old behavior for backing-file-name if it is given.

Hmm. Or, probably, we can use direct base for base-filename? And in cases
when we should skip filters (for example of parallel jobs) user should
specify backing-file explicitly?


The backing_file_str is always specified if the base is specified and is 
always equal to the base->filename. So, the user's backing file name is 
always NULL for the stream job. Furthermore, it is not checked for being 
the correct backing node and can lead to a wrong record in the QCOW2 header.


Andrey




---
  block/monitor/block-hmp-cmds.c |  2 +-
  block/stream.c |  6 +-
  blockdev.c | 17 +
  include/block/block_int.h  |  2 +-
  qapi/block-core.json   | 17 +
  5 files changed, 5 insertions(+), 39 deletions(-)

diff --git a/block/monitor/block-hmp-cmds.c 
b/block/monitor/block-hmp-cmds.c

index 4e66775..5f19499 100644
--- a/block/monitor/block-hmp-cmds.c
+++ b/block/monitor/block-hmp-cmds.c
@@ -506,7 +506,7 @@ void hmp_block_stream(Monitor *mon, const QDict 
*qdict)

  int64_t speed = qdict_get_try_int(qdict, "speed", 0);
  qmp_block_stream(true, device, device, base != NULL, base, 
false, NULL,
- false, NULL, qdict_haskey(qdict, "speed"), 
speed, true,

+ qdict_haskey(qdict, "speed"), speed, true,
   BLOCKDEV_ON_ERROR_REPORT, false, NULL, false, 
false, false,

   false, );
diff --git a/block/stream.c b/block/stream.c
index b0719e9..fe2663f 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -34,7 +34,6 @@ typedef struct StreamBlockJob {
  BlockDriverState *base_overlay; /* COW overlay (stream from 
this) */

  BlockDriverState *above_base;   /* Node directly above the base */
  BlockdevOnError on_error;
-    char *backing_file_str;
  bool bs_read_only;
  bool chain_frozen;
  } StreamBlockJob;
@@ -103,8 +102,6 @@ static void stream_clean(Job *job)
  blk_set_perm(bjob->blk, 0, BLK_PERM_ALL, _abort);
  bdrv_reopen_set_read_only(bs, true, NULL);
  }
-
-    g_free(s->backing_file_str);
  }
  static int coroutine_fn stream_run(Job *job, Error **errp)
@@ -220,7 +217,7 @@ static const BlockJobDriver stream_job_driver = {
  };
  void stream_start(const char *job_id, BlockDriverState *bs,
-  BlockDriverState *base, const char *backing_file_str,
+  BlockDriverState *base,
    int creation_flags, int64_t speed,
    BlockdevOnError on_error,
    const char *filter_node_name,
@@ -295,7 +292,6 @@ void stream_start(const char *job_id, 
BlockDriverState *bs,

  s->base_overlay = base_overlay;
  s->above_base = above_base;
-    s->backing_file_str = g_strdup(backing_file_str);
  s->bs_read_only = bs_read_only;
  s->chain_frozen = true;
diff --git a/blockdev.c b/blockdev.c
index d719c47..b223601 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2486,7 +2486,6 @@ out:
  void qmp_block_stream(bool has_job_id, const char *job_id, const 
char *device,

    bool has_base, const char *base,
    bool has_base_node, const char *base_node,
-  bool has_backing_file, const char *backing_file,
    bool has_speed, int64_t speed,
    bool has_on_error, BlockdevOnError on_error,
    bool has_filter_node_name, const char 
*filter_node_name,
@@ -2498,7 +2497,6 @@ void qmp_block_stream(bool has_job_id, const 
char *job_id, const char *device,

  BlockDriverState *base_bs = NULL;
  AioContext *aio_context;
  Error *local_err = NULL;
-    const char *base_name = NULL;
  int job_flags = JOB_DEFAULT;
  if (!has_on_error) {
@@ -2526,7 +2524,6 @@ void qmp_block_stream(bool has_job_id, const 
char *job_id, const char *device,

  goto out;
  }
  assert(bdrv_get_aio_context(base_bs) == aio_context);
-    base_name = base;
  }
  if (has_base_node) {
@@ -2541,7 +2538,6 @@ void qmp_block_stream(bool has_job_id, const 
char *job_id, const char *device,

  }
  assert(bdrv_get_aio_context(base_bs) == aio_context);
  bdrv_refresh_filename(base_bs);
-    base_name = base_bs->filename;
  }
  /* Check for op blockers 

Re: [PATCH v10 8/9] block: remove unused backing-file name parameter

2020-10-07 Thread Vladimir Sementsov-Ogievskiy

29.09.2020 15:38, Andrey Shinkevich wrote:

The block stream QMP parameter backing-file is in use no more. It
designates a backing file name to set in QCOW2 image header after the
block stream job finished. The base file name is used instead.

Signed-off-by: Andrey Shinkevich 


We can't just remove it without a deprecation period of three releases.

So actually, in a previous patch, we should implement new behavior for
automatic backing-file detection if this parameter is unspecified. Amd
keep old behavior for backing-file-name if it is given.

Hmm. Or, probably, we can use direct base for base-filename? And in cases
when we should skip filters (for example of parallel jobs) user should
specify backing-file explicitly?


---
  block/monitor/block-hmp-cmds.c |  2 +-
  block/stream.c |  6 +-
  blockdev.c | 17 +
  include/block/block_int.h  |  2 +-
  qapi/block-core.json   | 17 +
  5 files changed, 5 insertions(+), 39 deletions(-)

diff --git a/block/monitor/block-hmp-cmds.c b/block/monitor/block-hmp-cmds.c
index 4e66775..5f19499 100644
--- a/block/monitor/block-hmp-cmds.c
+++ b/block/monitor/block-hmp-cmds.c
@@ -506,7 +506,7 @@ void hmp_block_stream(Monitor *mon, const QDict *qdict)
  int64_t speed = qdict_get_try_int(qdict, "speed", 0);
  
  qmp_block_stream(true, device, device, base != NULL, base, false, NULL,

- false, NULL, qdict_haskey(qdict, "speed"), speed, true,
+ qdict_haskey(qdict, "speed"), speed, true,
   BLOCKDEV_ON_ERROR_REPORT, false, NULL, false, false, 
false,
   false, );
  
diff --git a/block/stream.c b/block/stream.c

index b0719e9..fe2663f 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -34,7 +34,6 @@ typedef struct StreamBlockJob {
  BlockDriverState *base_overlay; /* COW overlay (stream from this) */
  BlockDriverState *above_base;   /* Node directly above the base */
  BlockdevOnError on_error;
-char *backing_file_str;
  bool bs_read_only;
  bool chain_frozen;
  } StreamBlockJob;
@@ -103,8 +102,6 @@ static void stream_clean(Job *job)
  blk_set_perm(bjob->blk, 0, BLK_PERM_ALL, _abort);
  bdrv_reopen_set_read_only(bs, true, NULL);
  }
-
-g_free(s->backing_file_str);
  }
  
  static int coroutine_fn stream_run(Job *job, Error **errp)

@@ -220,7 +217,7 @@ static const BlockJobDriver stream_job_driver = {
  };
  
  void stream_start(const char *job_id, BlockDriverState *bs,

-  BlockDriverState *base, const char *backing_file_str,
+  BlockDriverState *base,
int creation_flags, int64_t speed,
BlockdevOnError on_error,
const char *filter_node_name,
@@ -295,7 +292,6 @@ void stream_start(const char *job_id, BlockDriverState *bs,
  
  s->base_overlay = base_overlay;

  s->above_base = above_base;
-s->backing_file_str = g_strdup(backing_file_str);
  s->bs_read_only = bs_read_only;
  s->chain_frozen = true;
  
diff --git a/blockdev.c b/blockdev.c

index d719c47..b223601 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2486,7 +2486,6 @@ out:
  void qmp_block_stream(bool has_job_id, const char *job_id, const char *device,
bool has_base, const char *base,
bool has_base_node, const char *base_node,
-  bool has_backing_file, const char *backing_file,
bool has_speed, int64_t speed,
bool has_on_error, BlockdevOnError on_error,
bool has_filter_node_name, const char *filter_node_name,
@@ -2498,7 +2497,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
  BlockDriverState *base_bs = NULL;
  AioContext *aio_context;
  Error *local_err = NULL;
-const char *base_name = NULL;
  int job_flags = JOB_DEFAULT;
  
  if (!has_on_error) {

@@ -2526,7 +2524,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
  goto out;
  }
  assert(bdrv_get_aio_context(base_bs) == aio_context);
-base_name = base;
  }
  
  if (has_base_node) {

@@ -2541,7 +2538,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
  }
  assert(bdrv_get_aio_context(base_bs) == aio_context);
  bdrv_refresh_filename(base_bs);
-base_name = base_bs->filename;
  }
  
  /* Check for op blockers in the whole chain between bs and base */

@@ -2553,17 +2549,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
  }
  }
  
-/* if we are streaming the entire chain, the result will have no backing

- * file, and specifying one is therefore an error */
-if (base_bs == NULL && has_backing_file) {
-error_setg(errp, "backing file 

[PATCH v10 8/9] block: remove unused backing-file name parameter

2020-09-29 Thread Andrey Shinkevich via
The block stream QMP parameter backing-file is in use no more. It
designates a backing file name to set in QCOW2 image header after the
block stream job finished. The base file name is used instead.

Signed-off-by: Andrey Shinkevich 
---
 block/monitor/block-hmp-cmds.c |  2 +-
 block/stream.c |  6 +-
 blockdev.c | 17 +
 include/block/block_int.h  |  2 +-
 qapi/block-core.json   | 17 +
 5 files changed, 5 insertions(+), 39 deletions(-)

diff --git a/block/monitor/block-hmp-cmds.c b/block/monitor/block-hmp-cmds.c
index 4e66775..5f19499 100644
--- a/block/monitor/block-hmp-cmds.c
+++ b/block/monitor/block-hmp-cmds.c
@@ -506,7 +506,7 @@ void hmp_block_stream(Monitor *mon, const QDict *qdict)
 int64_t speed = qdict_get_try_int(qdict, "speed", 0);
 
 qmp_block_stream(true, device, device, base != NULL, base, false, NULL,
- false, NULL, qdict_haskey(qdict, "speed"), speed, true,
+ qdict_haskey(qdict, "speed"), speed, true,
  BLOCKDEV_ON_ERROR_REPORT, false, NULL, false, false, 
false,
  false, );
 
diff --git a/block/stream.c b/block/stream.c
index b0719e9..fe2663f 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -34,7 +34,6 @@ typedef struct StreamBlockJob {
 BlockDriverState *base_overlay; /* COW overlay (stream from this) */
 BlockDriverState *above_base;   /* Node directly above the base */
 BlockdevOnError on_error;
-char *backing_file_str;
 bool bs_read_only;
 bool chain_frozen;
 } StreamBlockJob;
@@ -103,8 +102,6 @@ static void stream_clean(Job *job)
 blk_set_perm(bjob->blk, 0, BLK_PERM_ALL, _abort);
 bdrv_reopen_set_read_only(bs, true, NULL);
 }
-
-g_free(s->backing_file_str);
 }
 
 static int coroutine_fn stream_run(Job *job, Error **errp)
@@ -220,7 +217,7 @@ static const BlockJobDriver stream_job_driver = {
 };
 
 void stream_start(const char *job_id, BlockDriverState *bs,
-  BlockDriverState *base, const char *backing_file_str,
+  BlockDriverState *base,
   int creation_flags, int64_t speed,
   BlockdevOnError on_error,
   const char *filter_node_name,
@@ -295,7 +292,6 @@ void stream_start(const char *job_id, BlockDriverState *bs,
 
 s->base_overlay = base_overlay;
 s->above_base = above_base;
-s->backing_file_str = g_strdup(backing_file_str);
 s->bs_read_only = bs_read_only;
 s->chain_frozen = true;
 
diff --git a/blockdev.c b/blockdev.c
index d719c47..b223601 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2486,7 +2486,6 @@ out:
 void qmp_block_stream(bool has_job_id, const char *job_id, const char *device,
   bool has_base, const char *base,
   bool has_base_node, const char *base_node,
-  bool has_backing_file, const char *backing_file,
   bool has_speed, int64_t speed,
   bool has_on_error, BlockdevOnError on_error,
   bool has_filter_node_name, const char *filter_node_name,
@@ -2498,7 +2497,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
 BlockDriverState *base_bs = NULL;
 AioContext *aio_context;
 Error *local_err = NULL;
-const char *base_name = NULL;
 int job_flags = JOB_DEFAULT;
 
 if (!has_on_error) {
@@ -2526,7 +2524,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
 goto out;
 }
 assert(bdrv_get_aio_context(base_bs) == aio_context);
-base_name = base;
 }
 
 if (has_base_node) {
@@ -2541,7 +2538,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
 }
 assert(bdrv_get_aio_context(base_bs) == aio_context);
 bdrv_refresh_filename(base_bs);
-base_name = base_bs->filename;
 }
 
 /* Check for op blockers in the whole chain between bs and base */
@@ -2553,17 +2549,6 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
 }
 }
 
-/* if we are streaming the entire chain, the result will have no backing
- * file, and specifying one is therefore an error */
-if (base_bs == NULL && has_backing_file) {
-error_setg(errp, "backing file specified, but streaming the "
- "entire chain");
-goto out;
-}
-
-/* backing_file string overrides base bs filename */
-base_name = has_backing_file ? backing_file : base_name;
-
 if (has_auto_finalize && !auto_finalize) {
 job_flags |= JOB_MANUAL_FINALIZE;
 }
@@ -2571,7 +2556,7 @@ void qmp_block_stream(bool has_job_id, const char 
*job_id, const char *device,
 job_flags |= JOB_MANUAL_DISMISS;
 }
 
-stream_start(has_job_id ? job_id : NULL, bs, base_bs, base_name,
+stream_start(has_job_id ?