qemu-kvm/kvm-block-bdrv-blk_co_unref-for-calls-in-coroutine-conte.patch

From 7baea25be90e184175dd5a919ee5878cbd4970c2 Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Thu, 4 May 2023 13:57:33 +0200
Subject: [PATCH 52/56] block: bdrv/blk_co_unref() for calls in coroutine
 context

RH-Author: Kevin Wolf <kwolf@redhat.com>
RH-MergeRequest: 164: block: Fix hangs in qmp_block_resize()
RH-Bugzilla: 2185688
RH-Acked-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
RH-Acked-by: Hanna Czenczek <hreitz@redhat.com>
RH-Acked-by: Eric Blake <eblake@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Commit: [1/4] 8ebf8486b082c30ca1b39a6ede35e471eaaccfa3 (kmwolf/centos-qemu-kvm)

These functions must not be called in coroutine context, because they
need write access to the graph.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit b2ab5f545fa1eaaf2955dd617bee19a8b3279786)
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block.c                                     |  2 +-
 block/crypto.c                              |  6 +++---
 block/parallels.c                           |  6 +++---
 block/qcow.c                                |  6 +++---
 block/qcow2.c                               | 14 +++++++-------
 block/qed.c                                 |  6 +++---
 block/vdi.c                                 |  6 +++---
 block/vhdx.c                                |  6 +++---
 block/vmdk.c                                | 18 +++++++++---------
 block/vpc.c                                 |  6 +++---
 include/block/block-global-state.h          |  3 ++-
 include/sysemu/block-backend-global-state.h |  5 ++++-
 12 files changed, 44 insertions(+), 40 deletions(-)

diff --git a/block.c b/block.c
index d79a52ca74..a48112f945 100644
--- a/block.c
+++ b/block.c
@@ -680,7 +680,7 @@ int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv,
 
     ret = 0;
 out:
-    blk_unref(blk);
+    blk_co_unref(blk);
     return ret;
 }
 
diff --git a/block/crypto.c b/block/crypto.c
index ca67289187..8fd3ad0054 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -355,7 +355,7 @@ block_crypto_co_create_generic(BlockDriverState *bs, int64_t size,
     ret = 0;
  cleanup:
     qcrypto_block_free(crypto);
-    blk_unref(blk);
+    blk_co_unref(blk);
     return ret;
 }
 
@@ -661,7 +661,7 @@ block_crypto_co_create_luks(BlockdevCreateOptions *create_options, Error **errp)
 
     ret = 0;
 fail:
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     return ret;
 }
 
@@ -730,7 +730,7 @@ fail:
         bdrv_co_delete_file_noerr(bs);
     }
 
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     qapi_free_QCryptoBlockCreateOptions(create_opts);
     qobject_unref(cryptoopts);
     return ret;
diff --git a/block/parallels.c b/block/parallels.c
index 013684801a..b49c35929e 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -613,8 +613,8 @@ static int coroutine_fn parallels_co_create(BlockdevCreateOptions* opts,
 
     ret = 0;
 out:
-    blk_unref(blk);
-    bdrv_unref(bs);
+    blk_co_unref(blk);
+    bdrv_co_unref(bs);
     return ret;
 
 exit:
@@ -691,7 +691,7 @@ parallels_co_create_opts(BlockDriver *drv, const char *filename,
 
 done:
     qobject_unref(qdict);
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
diff --git a/block/qcow.c b/block/qcow.c
index 490e4f819e..a0c701f578 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -915,8 +915,8 @@ static int coroutine_fn qcow_co_create(BlockdevCreateOptions *opts,
     g_free(tmp);
     ret = 0;
 exit:
-    blk_unref(qcow_blk);
-    bdrv_unref(bs);
+    blk_co_unref(qcow_blk);
+    bdrv_co_unref(bs);
     qcrypto_block_free(crypto);
     return ret;
 }
@@ -1015,7 +1015,7 @@ qcow_co_create_opts(BlockDriver *drv, const char *filename,
 fail:
     g_free(backing_fmt);
     qobject_unref(qdict);
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
diff --git a/block/qcow2.c b/block/qcow2.c
index 22084730f9..0b8beb8b47 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -3711,7 +3711,7 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
         goto out;
     }
 
-    blk_unref(blk);
+    blk_co_unref(blk);
     blk = NULL;
 
     /*
@@ -3791,7 +3791,7 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
         }
     }
 
-    blk_unref(blk);
+    blk_co_unref(blk);
     blk = NULL;
 
     /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning.
@@ -3816,9 +3816,9 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
 
     ret = 0;
 out:
-    blk_unref(blk);
-    bdrv_unref(bs);
-    bdrv_unref(data_bs);
+    blk_co_unref(blk);
+    bdrv_co_unref(bs);
+    bdrv_co_unref(data_bs);
     return ret;
 }
 
@@ -3949,8 +3949,8 @@ finish:
     }
 
     qobject_unref(qdict);
-    bdrv_unref(bs);
-    bdrv_unref(data_bs);
+    bdrv_co_unref(bs);
+    bdrv_co_unref(data_bs);
     qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
diff --git a/block/qed.c b/block/qed.c
index 0705a7b4e2..aff2a2076e 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -748,8 +748,8 @@ static int coroutine_fn bdrv_qed_co_create(BlockdevCreateOptions *opts,
     ret = 0; /* success */
 out:
     g_free(l1_table);
-    blk_unref(blk);
-    bdrv_unref(bs);
+    blk_co_unref(blk);
+    bdrv_co_unref(bs);
     return ret;
 }
 
@@ -819,7 +819,7 @@ bdrv_qed_co_create_opts(BlockDriver *drv, const char *filename,
 
 fail:
     qobject_unref(qdict);
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
diff --git a/block/vdi.c b/block/vdi.c
index f2434d6153..08331d2dd7 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -886,8 +886,8 @@ static int coroutine_fn vdi_co_do_create(BlockdevCreateOptions *create_options,
 
     ret = 0;
 exit:
-    blk_unref(blk);
-    bdrv_unref(bs_file);
+    blk_co_unref(blk);
+    bdrv_co_unref(bs_file);
     g_free(bmap);
     return ret;
 }
@@ -975,7 +975,7 @@ vdi_co_create_opts(BlockDriver *drv, const char *filename,
 done:
     qobject_unref(qdict);
     qapi_free_BlockdevCreateOptions(create_options);
-    bdrv_unref(bs_file);
+    bdrv_co_unref(bs_file);
     return ret;
 }
 
diff --git a/block/vhdx.c b/block/vhdx.c
index 81420722a1..00777da91a 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -2053,8 +2053,8 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
 
     ret = 0;
 delete_and_exit:
-    blk_unref(blk);
-    bdrv_unref(bs);
+    blk_co_unref(blk);
+    bdrv_co_unref(bs);
     g_free(creator);
     return ret;
 }
@@ -2144,7 +2144,7 @@ vhdx_co_create_opts(BlockDriver *drv, const char *filename,
 
 fail:
     qobject_unref(qdict);
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
diff --git a/block/vmdk.c b/block/vmdk.c
index f5f49018fe..01ca13c82b 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -2306,7 +2306,7 @@ exit:
         if (pbb) {
             *pbb = blk;
         } else {
-            blk_unref(blk);
+            blk_co_unref(blk);
             blk = NULL;
         }
     }
@@ -2516,12 +2516,12 @@ vmdk_co_do_create(int64_t size,
         if (strcmp(blk_bs(backing)->drv->format_name, "vmdk")) {
             error_setg(errp, "Invalid backing file format: %s. Must be vmdk",
                        blk_bs(backing)->drv->format_name);
-            blk_unref(backing);
+            blk_co_unref(backing);
             ret = -EINVAL;
             goto exit;
         }
         ret = vmdk_read_cid(blk_bs(backing), 0, &parent_cid);
-        blk_unref(backing);
+        blk_co_unref(backing);
         if (ret) {
             error_setg(errp, "Failed to read parent CID");
             goto exit;
@@ -2542,14 +2542,14 @@ vmdk_co_do_create(int64_t size,
                              blk_bs(extent_blk)->filename);
         created_size += cur_size;
         extent_idx++;
-        blk_unref(extent_blk);
+        blk_co_unref(extent_blk);
     }
 
     /* Check whether we got excess extents */
     extent_blk = extent_fn(-1, extent_idx, flat, split, compress, zeroed_grain,
                            opaque, NULL);
     if (extent_blk) {
-        blk_unref(extent_blk);
+        blk_co_unref(extent_blk);
         error_setg(errp, "List of extents contains unused extents");
         ret = -EINVAL;
         goto exit;
@@ -2590,7 +2590,7 @@ vmdk_co_do_create(int64_t size,
     ret = 0;
 exit:
     if (blk) {
-        blk_unref(blk);
+        blk_co_unref(blk);
     }
     g_free(desc);
     g_free(parent_desc_line);
@@ -2641,7 +2641,7 @@ vmdk_co_create_opts_cb(int64_t size, int idx, bool flat, bool split,
                            errp)) {
         goto exit;
     }
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
 exit:
     g_free(ext_filename);
     return blk;
@@ -2797,12 +2797,12 @@ static BlockBackend * coroutine_fn vmdk_co_create_cb(int64_t size, int idx,
         return NULL;
     }
     blk_set_allow_write_beyond_eof(blk, true);
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
 
     if (size != -1) {
         ret = vmdk_init_extent(blk, size, flat, compress, zeroed_grain, errp);
         if (ret) {
-            blk_unref(blk);
+            blk_co_unref(blk);
             blk = NULL;
         }
     }
diff --git a/block/vpc.c b/block/vpc.c
index b89b0ff8e2..07ddda5b99 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -1082,8 +1082,8 @@ static int coroutine_fn vpc_co_create(BlockdevCreateOptions *opts,
     }
 
 out:
-    blk_unref(blk);
-    bdrv_unref(bs);
+    blk_co_unref(blk);
+    bdrv_co_unref(bs);
     return ret;
 }
 
@@ -1162,7 +1162,7 @@ vpc_co_create_opts(BlockDriver *drv, const char *filename,
 
 fail:
     qobject_unref(qdict);
-    bdrv_unref(bs);
+    bdrv_co_unref(bs);
     qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h
index 399200a9a3..cd4ea554bf 100644
--- a/include/block/block-global-state.h
+++ b/include/block/block-global-state.h
@@ -214,7 +214,8 @@ void bdrv_img_create(const char *filename, const char *fmt,
                      bool quiet, Error **errp);
 
 void bdrv_ref(BlockDriverState *bs);
-void bdrv_unref(BlockDriverState *bs);
+void no_coroutine_fn bdrv_unref(BlockDriverState *bs);
+void coroutine_fn no_co_wrapper bdrv_co_unref(BlockDriverState *bs);
 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child);
 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
                              BlockDriverState *child_bs,
diff --git a/include/sysemu/block-backend-global-state.h b/include/sysemu/block-backend-global-state.h
index 2b6d27db7c..fa83f9389c 100644
--- a/include/sysemu/block-backend-global-state.h
+++ b/include/sysemu/block-backend-global-state.h
@@ -42,7 +42,10 @@ blk_co_new_open(const char *filename, const char *reference, QDict *options,
 
 int blk_get_refcnt(BlockBackend *blk);
 void blk_ref(BlockBackend *blk);
-void blk_unref(BlockBackend *blk);
+
+void no_coroutine_fn blk_unref(BlockBackend *blk);
+void coroutine_fn no_co_wrapper blk_co_unref(BlockBackend *blk);
+
 void blk_remove_all_bs(void);
 BlockBackend *blk_by_name(const char *name);
 BlockBackend *blk_next(BlockBackend *blk);
-- 
2.39.1