block: Mark bdrv_co_create() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_create() need to hold a reader lock for the graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-17-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block.c

@@ -533,6 +533,7 @@ int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename,
     int ret;
     GLOBAL_STATE_CODE();
     ERRP_GUARD();
+    assert_bdrv_graph_readable();
 
     if (!drv->bdrv_co_create_opts) {
         error_setg(errp, "Driver '%s' does not support image creation",

block/create.c

@@ -43,6 +43,7 @@ static int coroutine_fn blockdev_create_run(Job *job, Error **errp)
     int ret;
 
     GLOBAL_STATE_CODE();
+    GRAPH_RDLOCK_GUARD();
 
     job_progress_set_remaining(&s->common, 1);
     ret = s->drv->bdrv_co_create(s->opts, errp);
@@ -59,6 +60,12 @@ static const JobDriver blockdev_create_job_driver = {
     .run           = blockdev_create_run,
 };
 
+/* Checking whether the function is present doesn't require the graph lock */
+static inline bool TSA_NO_TSA has_bdrv_co_create(BlockDriver *drv)
+{
+    return drv->bdrv_co_create;
+}
+
 void qmp_blockdev_create(const char *job_id, BlockdevCreateOptions *options,
                          Error **errp)
 {
@@ -79,7 +86,7 @@ void qmp_blockdev_create(const char *job_id, BlockdevCreateOptions *options,
     }
 
     /* Error out if the driver doesn't support .bdrv_co_create */
-    if (!drv->bdrv_co_create) {
+    if (!has_bdrv_co_create(drv)) {
         error_setg(errp, "Driver does not support blockdev-create");
         return;
     }

block/crypto.c

@@ -664,10 +664,9 @@ fail:
     return ret;
 }
 
-static int coroutine_fn block_crypto_co_create_opts_luks(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                                         const char *filename,
+block_crypto_co_create_opts_luks(BlockDriver *drv, const char *filename,
-                                                         QemuOpts *opts,
+                                 QemuOpts *opts, Error **errp)
-                                                         Error **errp)
 {
     QCryptoBlockCreateOptions *create_opts = NULL;
     BlockDriverState *bs = NULL;

block/file-posix.c

@@ -2607,10 +2607,9 @@ out:
     return result;
 }
 
-static int coroutine_fn raw_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                           const char *filename,
+raw_co_create_opts(BlockDriver *drv, const char *filename,
-                                           QemuOpts *opts,
+                   QemuOpts *opts, Error **errp)
-                                           Error **errp)
 {
     BlockdevCreateOptions options;
     int64_t total_size = 0;

block/file-win32.c

@@ -613,10 +613,9 @@ static int raw_co_create(BlockdevCreateOptions *options, Error **errp)
     return 0;
 }
 
-static int coroutine_fn raw_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                           const char *filename,
+raw_co_create_opts(BlockDriver *drv, const char *filename,
-                                           QemuOpts *opts,
+                   QemuOpts *opts, Error **errp)
-                                           Error **errp)
 {
     BlockdevCreateOptions options;
     int64_t total_size = 0;

block/parallels.c

@@ -622,10 +622,9 @@ exit:
     goto out;
 }
 
-static int coroutine_fn parallels_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                                 const char *filename,
+parallels_co_create_opts(BlockDriver *drv, const char *filename,
-                                                 QemuOpts *opts,
+                         QemuOpts *opts, Error **errp)
-                                                 Error **errp)
 {
     BlockdevCreateOptions *create_options = NULL;
     BlockDriverState *bs = NULL;

block/qcow.c

@@ -921,9 +921,9 @@ exit:
     return ret;
 }
 
-static int coroutine_fn qcow_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                            const char *filename,
+qcow_co_create_opts(BlockDriver *drv, const char *filename,
-                                            QemuOpts *opts, Error **errp)
+                    QemuOpts *opts, Error **errp)
 {
     BlockdevCreateOptions *create_options = NULL;
     BlockDriverState *bs = NULL;

block/qcow2.c

@@ -3816,10 +3816,9 @@ out:
     return ret;
 }
 
-static int coroutine_fn qcow2_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                             const char *filename,
+qcow2_co_create_opts(BlockDriver *drv, const char *filename, QemuOpts *opts,
-                                             QemuOpts *opts,
+                     Error **errp)
-                                             Error **errp)
 {
     BlockdevCreateOptions *create_options = NULL;
     QDict *qdict;

block/qed.c

@@ -754,10 +754,9 @@ out:
     return ret;
 }
 
-static int coroutine_fn bdrv_qed_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                                const char *filename,
+bdrv_qed_co_create_opts(BlockDriver *drv, const char *filename,
-                                                QemuOpts *opts,
+                        QemuOpts *opts, Error **errp)
-                                                Error **errp)
 {
     BlockdevCreateOptions *create_options = NULL;
     QDict *qdict;

block/raw-format.c

@@ -430,10 +430,9 @@ static int raw_has_zero_init(BlockDriverState *bs)
     return bdrv_has_zero_init(bs->file->bs);
 }
 
-static int coroutine_fn raw_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                           const char *filename,
+raw_co_create_opts(BlockDriver *drv, const char *filename,
-                                           QemuOpts *opts,
+                   QemuOpts *opts, Error **errp)
-                                           Error **errp)
 {
     return bdrv_co_create_file(filename, opts, errp);
 }

block/vdi.c

@@ -898,10 +898,9 @@ static int coroutine_fn vdi_co_create(BlockdevCreateOptions *create_options,
     return vdi_co_do_create(create_options, DEFAULT_CLUSTER_SIZE, errp);
 }
 
-static int coroutine_fn vdi_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                           const char *filename,
+vdi_co_create_opts(BlockDriver *drv, const char *filename,
-                                           QemuOpts *opts,
+                   QemuOpts *opts, Error **errp)
-                                           Error **errp)
 {
     QDict *qdict = NULL;
     BlockdevCreateOptions *create_options = NULL;

block/vhdx.c

@@ -2059,10 +2059,9 @@ delete_and_exit:
     return ret;
 }
 
-static int coroutine_fn vhdx_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                            const char *filename,
+vhdx_co_create_opts(BlockDriver *drv, const char *filename,
-                                            QemuOpts *opts,
+                    QemuOpts *opts, Error **errp)
-                                            Error **errp)
 {
     BlockdevCreateOptions *create_options = NULL;
     QDict *qdict;

block/vmdk.c

@@ -2277,11 +2277,10 @@ exit:
     return ret;
 }
 
-static int coroutine_fn vmdk_create_extent(const char *filename,
+static int coroutine_fn GRAPH_RDLOCK
-                                           int64_t filesize, bool flat,
+vmdk_create_extent(const char *filename, int64_t filesize, bool flat,
-                                           bool compress, bool zeroed_grain,
+                   bool compress, bool zeroed_grain, BlockBackend **pbb,
-                                           BlockBackend **pbb,
+                   QemuOpts *opts, Error **errp)
-                                           QemuOpts *opts, Error **errp)
 {
     int ret;
     BlockBackend *blk = NULL;
@@ -2359,14 +2358,10 @@ static int filename_decompose(const char *filename, char *path, char *prefix,
  *           non-split format.
  * idx >= 1: get the n-th extent if in a split subformat
  */
-typedef BlockBackend * coroutine_fn (*vmdk_create_extent_fn)(int64_t size,
+typedef BlockBackend * coroutine_fn /* GRAPH_RDLOCK */
-                                                             int idx,
+    (*vmdk_create_extent_fn)(int64_t size, int idx, bool flat, bool split,
-                                                             bool flat,
+                             bool compress, bool zeroed_grain, void *opaque,
-                                                             bool split,
+                             Error **errp);
-                                                             bool compress,
-                                                             bool zeroed_grain,
-                                                             void *opaque,
-                                                             Error **errp);
 
 static void vmdk_desc_add_extent(GString *desc,
                                  const char *extent_line_fmt,
@@ -2379,17 +2374,18 @@ static void vmdk_desc_add_extent(GString *desc,
     g_free(basename);
 }
 
-static int coroutine_fn vmdk_co_do_create(int64_t size,
+static int coroutine_fn GRAPH_RDLOCK
-                                          BlockdevVmdkSubformat subformat,
+vmdk_co_do_create(int64_t size,
-                                          BlockdevVmdkAdapterType adapter_type,
+                  BlockdevVmdkSubformat subformat,
-                                          const char *backing_file,
+                  BlockdevVmdkAdapterType adapter_type,
-                                          const char *hw_version,
+                  const char *backing_file,
-                                          const char *toolsversion,
+                  const char *hw_version,
-                                          bool compat6,
+                  const char *toolsversion,
-                                          bool zeroed_grain,
+                  bool compat6,
-                                          vmdk_create_extent_fn extent_fn,
+                  bool zeroed_grain,
-                                          void *opaque,
+                  vmdk_create_extent_fn extent_fn,
-                                          Error **errp)
+                  void *opaque,
+                  Error **errp)
 {
     int extent_idx;
     BlockBackend *blk = NULL;
@@ -2609,10 +2605,10 @@ typedef struct {
     QemuOpts *opts;
 } VMDKCreateOptsData;
 
-static BlockBackend * coroutine_fn vmdk_co_create_opts_cb(int64_t size, int idx,
+static BlockBackend * coroutine_fn GRAPH_RDLOCK
-                                            bool flat, bool split, bool compress,
+vmdk_co_create_opts_cb(int64_t size, int idx, bool flat, bool split,
-                                            bool zeroed_grain, void *opaque,
+                       bool compress, bool zeroed_grain, void *opaque,
-                                            Error **errp)
+                       Error **errp)
 {
     BlockBackend *blk = NULL;
     BlockDriverState *bs = NULL;
@@ -2651,10 +2647,9 @@ exit:
     return blk;
 }
 
-static int coroutine_fn vmdk_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                            const char *filename,
+vmdk_co_create_opts(BlockDriver *drv, const char *filename,
-                                            QemuOpts *opts,
+                    QemuOpts *opts, Error **errp)
-                                            Error **errp)
 {
     Error *local_err = NULL;
     char *desc = NULL;
@@ -2814,8 +2809,8 @@ static BlockBackend * coroutine_fn vmdk_co_create_cb(int64_t size, int idx,
     return blk;
 }
 
-static int coroutine_fn vmdk_co_create(BlockdevCreateOptions *create_options,
+static int coroutine_fn GRAPH_RDLOCK
-                                       Error **errp)
+vmdk_co_create(BlockdevCreateOptions *create_options, Error **errp)
 {
     BlockdevCreateOptionsVmdk *opts;
 

block/vpc.c

@@ -1087,10 +1087,9 @@ out:
     return ret;
 }
 
-static int coroutine_fn vpc_co_create_opts(BlockDriver *drv,
+static int coroutine_fn GRAPH_RDLOCK
-                                           const char *filename,
+vpc_co_create_opts(BlockDriver *drv, const char *filename,
-                                           QemuOpts *opts,
+                   QemuOpts *opts, Error **errp)
-                                           Error **errp)
 {
     BlockdevCreateOptions *create_options = NULL;
     QDict *qdict;

include/block/block-global-state.h

@@ -58,13 +58,15 @@ BlockDriver *bdrv_find_protocol(const char *filename,
                                 Error **errp);
 BlockDriver *bdrv_find_format(const char *format_name);
 
-int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename,
+int coroutine_fn GRAPH_RDLOCK
-                                QemuOpts *opts, Error **errp);
+bdrv_co_create(BlockDriver *drv, const char *filename, QemuOpts *opts,
-int co_wrapper bdrv_create(BlockDriver *drv, const char *filename,
+               Error **errp);
-                           QemuOpts *opts, Error **errp);
 
-int coroutine_fn bdrv_co_create_file(const char *filename, QemuOpts *opts,
+int co_wrapper_bdrv_rdlock bdrv_create(BlockDriver *drv, const char *filename,
-                                     Error **errp);
+                                       QemuOpts *opts, Error **errp);
+
+int coroutine_fn GRAPH_RDLOCK
+bdrv_co_create_file(const char *filename, QemuOpts *opts, Error **errp);
 
 BlockDriverState *bdrv_new(void);
 int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,

include/block/block_int-common.h

@@ -246,12 +246,11 @@ struct BlockDriver {
                           Error **errp);
     void (*bdrv_close)(BlockDriverState *bs);
 
-    int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts,
+    int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_create)(
-                                       Error **errp);
+        BlockdevCreateOptions *opts, Error **errp);
-    int coroutine_fn (*bdrv_co_create_opts)(BlockDriver *drv,
+
-                                            const char *filename,
+    int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_create_opts)(
-                                            QemuOpts *opts,
+        BlockDriver *drv, const char *filename, QemuOpts *opts, Error **errp);
-                                            Error **errp);
 
     int (*bdrv_amend_options)(BlockDriverState *bs,
                               QemuOpts *opts,