block: Mark bdrv_co_pdiscard() and callers GRAPH_RDLOCK

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

For some places, we know that they will hold the lock, but we don't have
the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock()
with a FIXME comment. These places will be removed once everything is
properly annotated.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-9-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/block/blkdebug.c b/block/blkdebug.c
index 5ba3766a2cc8bc8ee4e90204a9edd8c85a784939..85060047076e424b0cc7668e98d58eb0789d1657 100644 (file)
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -712,8 +712,8 @@ static int coroutine_fn blkdebug_co_pwrite_zeroes(BlockDriverState *bs,
     return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
 }
 
-static int coroutine_fn blkdebug_co_pdiscard(BlockDriverState *bs,
-                                             int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+blkdebug_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     uint32_t align = bs->bl.pdiscard_alignment;
     int err;

diff --git a/block/blklogwrites.c b/block/blklogwrites.c
index 5ec1d23f29f6c42c039a5ed0d06f11c727268162..3033f5035bc49779814ad546e5145e6f41135563 100644 (file)
--- a/block/blklogwrites.c
+++ b/block/blklogwrites.c
@@ -450,7 +450,7 @@ blk_log_writes_co_do_file_flush(BlkLogWritesFileReq *fr)
     return bdrv_co_flush(fr->bs->file->bs);
 }
 
-static int coroutine_fn
+static int coroutine_fn GRAPH_RDLOCK
 blk_log_writes_co_do_file_pdiscard(BlkLogWritesFileReq *fr)
 {
     return bdrv_co_pdiscard(fr->bs->file, fr->offset, fr->bytes);
@@ -483,10 +483,9 @@ blk_log_writes_co_flush_to_disk(BlockDriverState *bs)
                                  LOG_FLUSH_FLAG, false);
 }
 
-static int coroutine_fn
+static int coroutine_fn GRAPH_RDLOCK
 blk_log_writes_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
-    assume_graph_lock(); /* FIXME */
     return blk_log_writes_co_log(bs, offset, bytes, NULL, 0,
                                  blk_log_writes_co_do_file_pdiscard,
                                  LOG_DISCARD_FLAG, false);

diff --git a/block/blkreplay.c b/block/blkreplay.c
index ce13fa5ba5040693cc4f979e0a0c6dd8b9fec9c5..c18d3a755d66cba816b757d31675b4385d390916 100644 (file)
--- a/block/blkreplay.c
+++ b/block/blkreplay.c
@@ -102,8 +102,8 @@ static int coroutine_fn blkreplay_co_pwrite_zeroes(BlockDriverState *bs,
     return ret;
 }
 
-static int coroutine_fn blkreplay_co_pdiscard(BlockDriverState *bs,
-                                              int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+blkreplay_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     uint64_t reqid = blkreplay_next_id();
     int ret = bdrv_co_pdiscard(bs->file, offset, bytes);

diff --git a/block/block-backend.c b/block/block-backend.c
index 3e58b95b8a3935ce6461f114a5d8b8c56ad60a02..b4d238794789c5eea5308b76a04f00522193903b 100644 (file)
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1719,6 +1719,7 @@ blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes)
     IO_CODE();
 
     blk_wait_while_drained(blk);
+    GRAPH_RDLOCK_GUARD();
 
     ret = blk_check_byte_request(blk, offset, bytes);
     if (ret < 0) {

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 4ba72c63093ea5bc850af61dcadb21c207d6837e..42b46e746a3ee18378906d96cb54c5506d6905c6 100644 (file)
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -149,8 +149,8 @@ static coroutine_fn int cbw_do_copy_before_write(BlockDriverState *bs,
     return 0;
 }
 
-static int coroutine_fn cbw_co_pdiscard(BlockDriverState *bs,
-                                        int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+cbw_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     int ret = cbw_do_copy_before_write(bs, offset, bytes, 0);
     if (ret < 0) {
@@ -322,8 +322,8 @@ cbw_co_snapshot_block_status(BlockDriverState *bs,
     return ret;
 }
 
-static int coroutine_fn cbw_co_pdiscard_snapshot(BlockDriverState *bs,
-                                                 int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+cbw_co_pdiscard_snapshot(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
 

diff --git a/block/copy-on-read.c b/block/copy-on-read.c
index 3280eb2febffe4a79778cfccdc145a62da563dbd..b564f1ca3f418bad5cfe1d2ad7a5f7c664175dac 100644 (file)
--- a/block/copy-on-read.c
+++ b/block/copy-on-read.c
@@ -200,8 +200,8 @@ static int coroutine_fn cor_co_pwrite_zeroes(BlockDriverState *bs,
 }
 
 
-static int coroutine_fn cor_co_pdiscard(BlockDriverState *bs,
-                                        int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+cor_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     return bdrv_co_pdiscard(bs->file, offset, bytes);
 }

diff --git a/block/filter-compress.c b/block/filter-compress.c
index 2e2a65966cfc227d2d0d05408fa16b33d205ba1d..083aaef53c4b2d1319ddfc827b4f8e7d657db400 100644 (file)
--- a/block/filter-compress.c
+++ b/block/filter-compress.c
@@ -92,8 +92,8 @@ static int coroutine_fn compress_co_pwrite_zeroes(BlockDriverState *bs,
 }
 
 
-static int coroutine_fn compress_co_pdiscard(BlockDriverState *bs,
-                                             int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+compress_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     return bdrv_co_pdiscard(bs->file, offset, bytes);
 }

diff --git a/block/io.c b/block/io.c
index cfc93dc912bdc7af63120805f77a2cb57b41c1d0..e97adb5ba4428b6f0ba9f8f91f6833276ee23a2e 100644 (file)
--- a/block/io.c
+++ b/block/io.c
@@ -2971,6 +2971,7 @@ int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset,
     int head, tail, align;
     BlockDriverState *bs = child->bs;
     IO_CODE();
+    assert_bdrv_graph_readable();
 
     if (!bs || !bs->drv || !bdrv_co_is_inserted(bs)) {
         return -ENOMEDIUM;
@@ -3577,6 +3578,7 @@ bdrv_co_pdiscard_snapshot(BlockDriverState *bs, int64_t offset, int64_t bytes)
     BlockDriver *drv = bs->drv;
     int ret;
     IO_CODE();
+    assert_bdrv_graph_readable();
 
     if (!drv) {
         return -ENOMEDIUM;

diff --git a/block/mirror.c b/block/mirror.c
index d1d79f2319deefaba6a6d57f1b0764433bbba18c..b67e8b14f80ca4bbbc0e54d2a5647192981d3995 100644 (file)
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1443,9 +1443,10 @@ static int coroutine_fn bdrv_mirror_top_preadv(BlockDriverState *bs,
     return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags);
 }
 
-static int coroutine_fn bdrv_mirror_top_do_write(BlockDriverState *bs,
-    MirrorMethod method, uint64_t offset, uint64_t bytes, QEMUIOVector *qiov,
-    int flags)
+static int coroutine_fn GRAPH_RDLOCK
+bdrv_mirror_top_do_write(BlockDriverState *bs, MirrorMethod method,
+                         uint64_t offset, uint64_t bytes, QEMUIOVector *qiov,
+                         int flags)
 {
     MirrorOp *op = NULL;
     MirrorBDSOpaque *s = bs->opaque;
@@ -1503,6 +1504,8 @@ static int coroutine_fn bdrv_mirror_top_pwritev(BlockDriverState *bs,
     int ret = 0;
     bool copy_to_target = false;
 
+    assume_graph_lock(); /* FIXME */
+
     if (s->job) {
         copy_to_target = s->job->ret >= 0 &&
                          !job_is_cancelled(&s->job->common.job) &&
@@ -1547,12 +1550,13 @@ static int coroutine_fn GRAPH_RDLOCK bdrv_mirror_top_flush(BlockDriverState *bs)
 static int coroutine_fn bdrv_mirror_top_pwrite_zeroes(BlockDriverState *bs,
     int64_t offset, int64_t bytes, BdrvRequestFlags flags)
 {
+    assume_graph_lock(); /* FIXME */
     return bdrv_mirror_top_do_write(bs, MIRROR_METHOD_ZERO, offset, bytes, NULL,
                                     flags);
 }
 
-static int coroutine_fn bdrv_mirror_top_pdiscard(BlockDriverState *bs,
-    int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+bdrv_mirror_top_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     return bdrv_mirror_top_do_write(bs, MIRROR_METHOD_DISCARD, offset, bytes,
                                     NULL, 0);

diff --git a/block/preallocate.c b/block/preallocate.c
index 483b596280fb1543b7b5afeb95380648da76cb87..c2c2dc8a8c339d1d66b96156f3e37533c985b78e 100644 (file)
--- a/block/preallocate.c
+++ b/block/preallocate.c
@@ -234,8 +234,8 @@ static coroutine_fn int preallocate_co_preadv_part(
                                flags);
 }
 
-static int coroutine_fn preallocate_co_pdiscard(BlockDriverState *bs,
-                                               int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+preallocate_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     return bdrv_co_pdiscard(bs->file, offset, bytes);
 }

diff --git a/block/raw-format.c b/block/raw-format.c
index 202acb123220f90acad8db16e199f446426e5029..7f1036ebed1a394af0ebef1957d9ee531c19de4f 100644 (file)
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -305,8 +305,8 @@ static int coroutine_fn raw_co_pwrite_zeroes(BlockDriverState *bs,
     return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
 }
 
-static int coroutine_fn raw_co_pdiscard(BlockDriverState *bs,
-                                        int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+raw_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     int ret;
 

diff --git a/block/snapshot-access.c b/block/snapshot-access.c
index 0a30ec6cd9aab4eb744a2376508efab79c2b7206..009cc4aea0db22305945a326d99ee7550e947214 100644 (file)
--- a/block/snapshot-access.c
+++ b/block/snapshot-access.c
@@ -49,8 +49,8 @@ snapshot_access_co_block_status(BlockDriverState *bs,
                                          bytes, pnum, map, file);
 }
 
-static int coroutine_fn snapshot_access_co_pdiscard(BlockDriverState *bs,
-                                             int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+snapshot_access_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     return bdrv_co_pdiscard_snapshot(bs->file->bs, offset, bytes);
 }

diff --git a/block/throttle.c b/block/throttle.c
index a0db8409273e5dcbb5a2307264806e9efa11c7cb..b07d853c0a23a29619ffcd24c0a8fc90ec372db7 100644 (file)
--- a/block/throttle.c
+++ b/block/throttle.c
@@ -144,8 +144,8 @@ static int coroutine_fn throttle_co_pwrite_zeroes(BlockDriverState *bs,
     return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
 }
 
-static int coroutine_fn throttle_co_pdiscard(BlockDriverState *bs,
-                                             int64_t offset, int64_t bytes)
+static int coroutine_fn GRAPH_RDLOCK
+throttle_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     ThrottleGroupMember *tgm = bs->opaque;
     throttle_group_co_io_limits_intercept(tgm, bytes, true);

diff --git a/include/block/block-io.h b/include/block/block-io.h
index 7e96506138dcff7032b776981f8ecc01a21d2d13..627061fd5f049a90ef808e5a9d6d8ab779bddab6 100644 (file)
--- a/include/block/block-io.h
+++ b/include/block/block-io.h
@@ -103,8 +103,9 @@ bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
 /* Ensure contents are flushed to disk.  */
 int coroutine_fn GRAPH_RDLOCK bdrv_co_flush(BlockDriverState *bs);
 
-int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset,
-                                  int64_t bytes);
+int coroutine_fn GRAPH_RDLOCK bdrv_co_pdiscard(BdrvChild *child, int64_t offset,
+                                               int64_t bytes);
+
 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
 int bdrv_block_status(BlockDriverState *bs, int64_t offset,
                       int64_t bytes, int64_t *pnum, int64_t *map,

diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h
index 51eaabd9d19e72fbf1ff95c46425deba42335b7f..c52190abdb595f13c3d1179efa8bba3bb7a8d2a8 100644 (file)
--- a/include/block/block_int-common.h
+++ b/include/block/block_int-common.h
@@ -479,8 +479,9 @@ struct BlockDriver {
         BdrvRequestFlags flags, BlockCompletionFunc *cb, void *opaque);
     BlockAIOCB * GRAPH_RDLOCK_PTR (*bdrv_aio_flush)(
         BlockDriverState *bs, BlockCompletionFunc *cb, void *opaque);
-    BlockAIOCB *(*bdrv_aio_pdiscard)(BlockDriverState *bs,
-        int64_t offset, int bytes,
+
+    BlockAIOCB * GRAPH_RDLOCK_PTR (*bdrv_aio_pdiscard)(
+        BlockDriverState *bs, int64_t offset, int bytes,
         BlockCompletionFunc *cb, void *opaque);
 
     int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
@@ -543,8 +544,9 @@ struct BlockDriver {
      */
     int coroutine_fn (*bdrv_co_pwrite_zeroes)(BlockDriverState *bs,
         int64_t offset, int64_t bytes, BdrvRequestFlags flags);
-    int coroutine_fn (*bdrv_co_pdiscard)(BlockDriverState *bs,
-        int64_t offset, int64_t bytes);
+
+    int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_pdiscard)(
+        BlockDriverState *bs, int64_t offset, int64_t bytes);
 
     /*
      * Map [offset, offset + nbytes) range onto a child of @bs to copy from,
@@ -632,8 +634,9 @@ struct BlockDriver {
     int coroutine_fn (*bdrv_co_snapshot_block_status)(BlockDriverState *bs,
         bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum,
         int64_t *map, BlockDriverState **file);
-    int coroutine_fn (*bdrv_co_pdiscard_snapshot)(BlockDriverState *bs,
-        int64_t offset, int64_t bytes);
+
+    int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_pdiscard_snapshot)(
+        BlockDriverState *bs, int64_t offset, int64_t bytes);
 
     /*
      * Invalidate any cached meta-data.

diff --git a/include/block/block_int-io.h b/include/block/block_int-io.h
index 4430bf4c4a462ed15d390ea020f25f8d1129c5c3..4bb6ccaa3412c012f117354f2ceb33442d99ebb0 100644 (file)
--- a/include/block/block_int-io.h
+++ b/include/block/block_int-io.h
@@ -40,7 +40,7 @@ int coroutine_fn bdrv_co_preadv_snapshot(BdrvChild *child,
 int coroutine_fn bdrv_co_snapshot_block_status(BlockDriverState *bs,
     bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum,
     int64_t *map, BlockDriverState **file);
-int coroutine_fn bdrv_co_pdiscard_snapshot(BlockDriverState *bs,
+int coroutine_fn GRAPH_RDLOCK bdrv_co_pdiscard_snapshot(BlockDriverState *bs,
     int64_t offset, int64_t bytes);