block: Rename BdrvChildRole to BdrvChildClass

This structure nearly only contains parent callbacks for child state
changes.  It cannot really reflect a child's role, because different
roles may overlap (as we will see when real roles are introduced), and
because parents can have custom callbacks even when the child fulfills a
standard role.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20200513110544.176672-4-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/backup-top.c

@@ -122,7 +122,7 @@ static void backup_top_refresh_filename(BlockDriverState *bs)
 }
 
 static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                  const BdrvChildRole *role,
+                                  const BdrvChildClass *child_class,
                                   BlockReopenQueue *reopen_queue,
                                   uint64_t perm, uint64_t shared,
                                   uint64_t *nperm, uint64_t *nshared)
@@ -142,7 +142,7 @@ static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
         return;
     }
 
-    if (role == &child_file) {
+    if (child_class == &child_file) {
         /*
          * Target child
          *
@@ -155,8 +155,8 @@ static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
         *nperm = BLK_PERM_WRITE;
     } else {
         /* Source child */
-        bdrv_filter_default_perms(bs, c, role, reopen_queue, perm, shared,
-                                  nperm, nshared);
+        bdrv_filter_default_perms(bs, c, child_class, reopen_queue,
+                                  perm, shared, nperm, nshared);
 
         if (perm & BLK_PERM_WRITE) {
             *nperm = *nperm | BLK_PERM_CONSISTENT_READ;

block/blkdebug.c

@@ -993,14 +993,14 @@ static int blkdebug_reopen_prepare(BDRVReopenState *reopen_state,
 }
 
 static void blkdebug_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                const BdrvChildRole *role,
+                                const BdrvChildClass *child_class,
                                 BlockReopenQueue *reopen_queue,
                                 uint64_t perm, uint64_t shared,
                                 uint64_t *nperm, uint64_t *nshared)
 {
     BDRVBlkdebugState *s = bs->opaque;
 
-    bdrv_filter_default_perms(bs, c, role, reopen_queue, perm, shared,
+    bdrv_filter_default_perms(bs, c, child_class, reopen_queue, perm, shared,
                               nperm, nshared);
 
     *nperm |= s->take_child_perms;

block/blklogwrites.c

@@ -282,7 +282,7 @@ static int64_t blk_log_writes_getlength(BlockDriverState *bs)
 }
 
 static void blk_log_writes_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                      const BdrvChildRole *role,
+                                      const BdrvChildClass *child_class,
                                       BlockReopenQueue *ro_q,
                                       uint64_t perm, uint64_t shrd,
                                       uint64_t *nperm, uint64_t *nshrd)
@@ -294,9 +294,11 @@ static void blk_log_writes_child_perm(BlockDriverState *bs, BdrvChild *c,
     }
 
     if (!strcmp(c->name, "log")) {
-        bdrv_format_default_perms(bs, c, role, ro_q, perm, shrd, nperm, nshrd);
+        bdrv_format_default_perms(bs, c, child_class, ro_q, perm, shrd, nperm,
+                                  nshrd);
     } else {
-        bdrv_filter_default_perms(bs, c, role, ro_q, perm, shrd, nperm, nshrd);
+        bdrv_filter_default_perms(bs, c, child_class, ro_q, perm, shrd, nperm,
+                                  nshrd);
     }
 }
 

block/block-backend.c

@@ -297,7 +297,7 @@ static void blk_root_detach(BdrvChild *child)
     }
 }
 
-static const BdrvChildRole child_root = {
+static const BdrvChildClass child_root = {
     .inherit_options    = blk_root_inherit_options,
 
     .change_media       = blk_root_change_media,
@@ -716,7 +716,7 @@ static BlockBackend *bdrv_first_blk(BlockDriverState *bs)
 {
     BdrvChild *child;
     QLIST_FOREACH(child, &bs->parents, next_parent) {
-        if (child->role == &child_root) {
+        if (child->klass == &child_root) {
             return child->opaque;
         }
     }
@@ -740,7 +740,7 @@ bool bdrv_is_root_node(BlockDriverState *bs)
     BdrvChild *c;
 
     QLIST_FOREACH(c, &bs->parents, next_parent) {
-        if (c->role != &child_root) {
+        if (c->klass != &child_root) {
             return false;
         }
     }

block/commit.c

@@ -223,7 +223,7 @@ static void bdrv_commit_top_refresh_filename(BlockDriverState *bs)
 }
 
 static void bdrv_commit_top_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                       const BdrvChildRole *role,
+                                       const BdrvChildClass *child_class,
                                        BlockReopenQueue *reopen_queue,
                                        uint64_t perm, uint64_t shared,
                                        uint64_t *nperm, uint64_t *nshared)

block/copy-on-read.c

@@ -51,7 +51,7 @@ static int cor_open(BlockDriverState *bs, QDict *options, int flags,
 #define PERM_UNCHANGED (BLK_PERM_ALL & ~PERM_PASSTHROUGH)
 
 static void cor_child_perm(BlockDriverState *bs, BdrvChild *c,
-                           const BdrvChildRole *role,
+                           const BdrvChildClass *child_class,
                            BlockReopenQueue *reopen_queue,
                            uint64_t perm, uint64_t shared,
                            uint64_t *nperm, uint64_t *nshared)

block/io.c

@@ -50,7 +50,7 @@ static void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore,
     BdrvChild *c, *next;
 
     QLIST_FOREACH_SAFE(c, &bs->parents, next_parent, next) {
-        if (c == ignore || (ignore_bds_parents && c->role->parent_is_bds)) {
+        if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) {
             continue;
         }
         bdrv_parent_drained_begin_single(c, false);
@@ -62,8 +62,8 @@ static void bdrv_parent_drained_end_single_no_poll(BdrvChild *c,
 {
     assert(c->parent_quiesce_counter > 0);
     c->parent_quiesce_counter--;
-    if (c->role->drained_end) {
-        c->role->drained_end(c, drained_end_counter);
+    if (c->klass->drained_end) {
+        c->klass->drained_end(c, drained_end_counter);
     }
 }
 
@@ -81,7 +81,7 @@ static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore,
     BdrvChild *c;
 
     QLIST_FOREACH(c, &bs->parents, next_parent) {
-        if (c == ignore || (ignore_bds_parents && c->role->parent_is_bds)) {
+        if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) {
             continue;
         }
         bdrv_parent_drained_end_single_no_poll(c, drained_end_counter);
@@ -90,8 +90,8 @@ static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore,
 
 static bool bdrv_parent_drained_poll_single(BdrvChild *c)
 {
-    if (c->role->drained_poll) {
-        return c->role->drained_poll(c);
+    if (c->klass->drained_poll) {
+        return c->klass->drained_poll(c);
     }
     return false;
 }
@@ -103,7 +103,7 @@ static bool bdrv_parent_drained_poll(BlockDriverState *bs, BdrvChild *ignore,
     bool busy = false;
 
     QLIST_FOREACH_SAFE(c, &bs->parents, next_parent, next) {
-        if (c == ignore || (ignore_bds_parents && c->role->parent_is_bds)) {
+        if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) {
             continue;
         }
         busy |= bdrv_parent_drained_poll_single(c);
@@ -115,8 +115,8 @@ static bool bdrv_parent_drained_poll(BlockDriverState *bs, BdrvChild *ignore,
 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll)
 {
     c->parent_quiesce_counter++;
-    if (c->role->drained_begin) {
-        c->role->drained_begin(c);
+    if (c->klass->drained_begin) {
+        c->klass->drained_begin(c);
     }
     if (poll) {
         BDRV_POLL_WHILE(c->bs, bdrv_parent_drained_poll_single(c));
@@ -3326,8 +3326,8 @@ static void bdrv_parent_cb_resize(BlockDriverState *bs)
 {
     BdrvChild *c;
     QLIST_FOREACH(c, &bs->parents, next_parent) {
-        if (c->role->resize) {
-            c->role->resize(c);
+        if (c->klass->resize) {
+            c->klass->resize(c);
         }
     }
 }

block/mirror.c

@@ -1492,7 +1492,7 @@ static void bdrv_mirror_top_refresh_filename(BlockDriverState *bs)
 }
 
 static void bdrv_mirror_top_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                       const BdrvChildRole *role,
+                                       const BdrvChildClass *child_class,
                                        BlockReopenQueue *reopen_queue,
                                        uint64_t perm, uint64_t shared,
                                        uint64_t *nperm, uint64_t *nshared)

block/quorum.c

@@ -1151,7 +1151,7 @@ static char *quorum_dirname(BlockDriverState *bs, Error **errp)
 }
 
 static void quorum_child_perm(BlockDriverState *bs, BdrvChild *c,
-                              const BdrvChildRole *role,
+                              const BdrvChildClass *child_class,
                               BlockReopenQueue *reopen_queue,
                               uint64_t perm, uint64_t shared,
                               uint64_t *nperm, uint64_t *nshared)

block/replication.c

@@ -163,7 +163,7 @@ static void replication_close(BlockDriverState *bs)
 }
 
 static void replication_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                   const BdrvChildRole *role,
+                                   const BdrvChildClass *child_class,
                                    BlockReopenQueue *reopen_queue,
                                    uint64_t perm, uint64_t shared,
                                    uint64_t *nperm, uint64_t *nshared)

block/vvfat.c

@@ -3136,7 +3136,7 @@ static void vvfat_qcow_options(int *child_flags, QDict *child_options,
     qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on");
 }
 
-static const BdrvChildRole child_vvfat_qcow = {
+static const BdrvChildClass child_vvfat_qcow = {
     .parent_is_bds      = true,
     .inherit_options    = vvfat_qcow_options,
 };
@@ -3210,14 +3210,14 @@ static int enable_write_target(BlockDriverState *bs, Error **errp)
 }
 
 static void vvfat_child_perm(BlockDriverState *bs, BdrvChild *c,
-                             const BdrvChildRole *role,
+                             const BdrvChildClass *child_class,
                              BlockReopenQueue *reopen_queue,
                              uint64_t perm, uint64_t shared,
                              uint64_t *nperm, uint64_t *nshared)
 {
     BDRVVVFATState *s = bs->opaque;
 
-    assert(c == s->qcow || role == &child_backing);
+    assert(c == s->qcow || child_class == &child_backing);
 
     if (c == s->qcow) {
         /* This is a private node, nobody should try to attach to it */

blockjob.c

@@ -163,7 +163,7 @@ static void child_job_set_aio_ctx(BdrvChild *c, AioContext *ctx,
     job->job.aio_context = ctx;
 }
 
-static const BdrvChildRole child_job = {
+static const BdrvChildClass child_job = {
     .get_parent_desc    = child_job_get_parent_desc,
     .drained_begin      = child_job_drained_begin,
     .drained_poll       = child_job_drained_poll,

include/block/block.h

@@ -13,7 +13,7 @@
 /* block.c */
 typedef struct BlockDriver BlockDriver;
 typedef struct BdrvChild BdrvChild;
-typedef struct BdrvChildRole BdrvChildRole;
+typedef struct BdrvChildClass BdrvChildClass;
 
 typedef struct BlockDriverInfo {
     /* in bytes, 0 if irrelevant */
@@ -296,7 +296,7 @@ int bdrv_parse_discard_flags(const char *mode, int *flags);
 BdrvChild *bdrv_open_child(const char *filename,
                            QDict *options, const char *bdref_key,
                            BlockDriverState* parent,
-                           const BdrvChildRole *child_role,
+                           const BdrvChildClass *child_class,
                            bool allow_none, Error **errp);
 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp);
 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
@@ -541,7 +541,7 @@ void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child);
 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
                              BlockDriverState *child_bs,
                              const char *child_name,
-                             const BdrvChildRole *child_role,
+                             const BdrvChildClass *child_class,
                              Error **errp);
 
 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);

include/block/block_int.h

@@ -556,14 +556,14 @@ struct BlockDriver {
      * the parents in @parent_perm and @parent_shared.
      *
      * If @c is NULL, return the permissions for attaching a new child for the
-     * given @role.
+     * given @child_class.
      *
      * If @reopen_queue is non-NULL, don't return the currently needed
      * permissions, but those that will be needed after applying the
      * @reopen_queue.
      */
      void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c,
-                             const BdrvChildRole *role,
+                             const BdrvChildClass *child_class,
                              BlockReopenQueue *reopen_queue,
                              uint64_t parent_perm, uint64_t parent_shared,
                              uint64_t *nperm, uint64_t *nshared);
@@ -665,7 +665,7 @@ typedef struct BdrvAioNotifier {
     QLIST_ENTRY(BdrvAioNotifier) list;
 } BdrvAioNotifier;
 
-struct BdrvChildRole {
+struct BdrvChildClass {
     /* If true, bdrv_replace_node() doesn't change the node this BdrvChild
      * points to. */
     bool stay_at_node;
@@ -738,14 +738,14 @@ struct BdrvChildRole {
     void (*set_aio_ctx)(BdrvChild *child, AioContext *ctx, GSList **ignore);
 };
 
-extern const BdrvChildRole child_file;
-extern const BdrvChildRole child_format;
-extern const BdrvChildRole child_backing;
+extern const BdrvChildClass child_file;
+extern const BdrvChildClass child_format;
+extern const BdrvChildClass child_backing;
 
 struct BdrvChild {
     BlockDriverState *bs;
     char *name;
-    const BdrvChildRole *role;
+    const BdrvChildClass *klass;
     void *opaque;
 
     /**
@@ -772,7 +772,7 @@ struct BdrvChild {
 
     /*
      * How many times the parent of this child has been drained
-     * (through role->drained_*).
+     * (through klass->drained_*).
      * Usually, this is equal to bs->quiesce_counter (potentially
      * reduced by bdrv_drain_all_count).  It may differ while the
      * child is entering or leaving a drained section.
@@ -1232,7 +1232,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
 
 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs,
                                   const char *child_name,
-                                  const BdrvChildRole *child_role,
+                                  const BdrvChildClass *child_class,
                                   AioContext *ctx,
                                   uint64_t perm, uint64_t shared_perm,
                                   void *opaque, Error **errp);
@@ -1263,7 +1263,7 @@ int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp);
  * block filters: Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED and RESIZE to
  * all children */
 void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c,
-                               const BdrvChildRole *role,
+                               const BdrvChildClass *child_class,
                                BlockReopenQueue *reopen_queue,
                                uint64_t perm, uint64_t shared,
                                uint64_t *nperm, uint64_t *nshared);
@@ -1273,7 +1273,7 @@ void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c,
  * requires WRITE | RESIZE for read-write images, always requires
  * CONSISTENT_READ and doesn't share WRITE. */
 void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,
-                               const BdrvChildRole *role,
+                               const BdrvChildClass *child_class,
                                BlockReopenQueue *reopen_queue,
                                uint64_t perm, uint64_t shared,
                                uint64_t *nperm, uint64_t *nshared);