Block patches:

- Refactoring for non-coroutine variants of bdrv/blk_co_* functions:
   Auto-generate more of them with the block coroutine wrapper generator
   script
 - iotest fixes
 - Both for the storage daemon and the system emulator: Fix PID file
   handling when daemonizing (store the absolute path and delete that on
   exit, which is necessary because daemonizing will change the working
   directory to /)
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Merge tag 'pull-block-2022-07-12' of https://gitlab.com/hreitz/qemu into staging

Block patches:
- Refactoring for non-coroutine variants of bdrv/blk_co_* functions:
  Auto-generate more of them with the block coroutine wrapper generator
  script
- iotest fixes
- Both for the storage daemon and the system emulator: Fix PID file
  handling when daemonizing (store the absolute path and delete that on
  exit, which is necessary because daemonizing will change the working
  directory to /)

# gpg: Signature made Tue 12 Jul 2022 19:04:14 BST
# gpg:                using RSA key CB62D7A0EE3829E45F004D34A1FA40D098019CDF
# gpg:                issuer "hreitz@redhat.com"
# gpg: Good signature from "Hanna Reitz <hreitz@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: CB62 D7A0 EE38 29E4 5F00  4D34 A1FA 40D0 9801 9CDF

* tag 'pull-block-2022-07-12' of https://gitlab.com/hreitz/qemu: (35 commits)
  vl: Unlink absolute PID file path
  vl: Conditionally register PID file unlink notifier
  qsd: Unlink absolute PID file path
  iotests/297: Have mypy ignore unused ignores
  qsd: Do not use error_report() before monitor_init
  block: Remove remaining unused symbols in coroutines.h
  block: Reorganize some declarations in block-backend-io.h
  block: Add blk_co_truncate()
  block: Add blk_co_ioctl()
  block: Implement blk_flush() using generated_co_wrapper
  block: Implement blk_pdiscard() using generated_co_wrapper
  block: Implement blk_pwrite_zeroes() using generated_co_wrapper
  block: Add blk_co_pwrite_compressed()
  block: Change blk_pwrite_compressed() param order
  block: Export blk_pwritev_part() in block-backend-io.h
  block: Add blk_[co_]preadv_part()
  block: Add blk_{preadv,pwritev}()
  block: Implement blk_{pread,pwrite}() using generated_co_wrapper
  block: Make blk_co_pwrite() take a const buffer
  block: Make 'bytes' param of blk_{pread,pwrite}() an int64_t
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

block.c

@@ -1037,7 +1037,7 @@ static int find_image_format(BlockBackend *file, const char *filename,
         return ret;
     }
 
-    ret = blk_pread(file, 0, buf, sizeof(buf));
+    ret = blk_pread(file, 0, sizeof(buf), buf, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not read image for determining its "
                          "format");
@@ -1045,14 +1045,16 @@ static int find_image_format(BlockBackend *file, const char *filename,
         return ret;
     }
 
-    drv = bdrv_probe_all(buf, ret, filename);
+    drv = bdrv_probe_all(buf, sizeof(buf), filename);
     if (!drv) {
         error_setg(errp, "Could not determine image format: No compatible "
                    "driver found");
-        ret = -ENOENT;
+        *pdrv = NULL;
+        return -ENOENT;
     }
+
     *pdrv = drv;
-    return ret;
+    return 0;
 }
 
 /**

block/blklogwrites.c

@@ -107,8 +107,8 @@ static uint64_t blk_log_writes_find_cur_log_sector(BdrvChild *log,
     struct log_write_entry cur_entry;
 
     while (cur_idx < nr_entries) {
-        int read_ret = bdrv_pread(log, cur_sector << sector_bits, &cur_entry,
-                                  sizeof(cur_entry));
+        int read_ret = bdrv_pread(log, cur_sector << sector_bits,
+                                  sizeof(cur_entry), &cur_entry, 0);
         if (read_ret < 0) {
             error_setg_errno(errp, -read_ret,
                              "Failed to read log entry %"PRIu64, cur_idx);
@@ -190,7 +190,7 @@ static int blk_log_writes_open(BlockDriverState *bs, QDict *options, int flags,
             log_sb.nr_entries = cpu_to_le64(0);
             log_sb.sectorsize = cpu_to_le32(BDRV_SECTOR_SIZE);
         } else {
-            ret = bdrv_pread(s->log_file, 0, &log_sb, sizeof(log_sb));
+            ret = bdrv_pread(s->log_file, 0, sizeof(log_sb), &log_sb, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret, "Could not read log superblock");
                 goto fail_log;

block/block-backend.c

@@ -1280,9 +1280,10 @@ static void coroutine_fn blk_wait_while_drained(BlockBackend *blk)
 }
 
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
-int coroutine_fn
-blk_co_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes,
-                 QEMUIOVector *qiov, BdrvRequestFlags flags)
+static int coroutine_fn
+blk_co_do_preadv_part(BlockBackend *blk, int64_t offset, int64_t bytes,
+                      QEMUIOVector *qiov, size_t qiov_offset,
+                      BdrvRequestFlags flags)
 {
     int ret;
     BlockDriverState *bs;
@@ -1307,11 +1308,23 @@ blk_co_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes,
                 bytes, false);
     }
 
-    ret = bdrv_co_preadv(blk->root, offset, bytes, qiov, flags);
+    ret = bdrv_co_preadv_part(blk->root, offset, bytes, qiov, qiov_offset,
+                              flags);
     bdrv_dec_in_flight(bs);
     return ret;
 }
 
+int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes,
+                              void *buf, BdrvRequestFlags flags)
+{
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
+    IO_OR_GS_CODE();
+
+    assert(bytes <= SIZE_MAX);
+
+    return blk_co_preadv(blk, offset, bytes, &qiov, flags);
+}
+
 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
                                int64_t bytes, QEMUIOVector *qiov,
                                BdrvRequestFlags flags)
@@ -1320,14 +1333,28 @@ int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
     IO_OR_GS_CODE();
 
     blk_inc_in_flight(blk);
-    ret = blk_co_do_preadv(blk, offset, bytes, qiov, flags);
+    ret = blk_co_do_preadv_part(blk, offset, bytes, qiov, 0, flags);
+    blk_dec_in_flight(blk);
+
+    return ret;
+}
+
+int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset,
+                                    int64_t bytes, QEMUIOVector *qiov,
+                                    size_t qiov_offset, BdrvRequestFlags flags)
+{
+    int ret;
+    IO_OR_GS_CODE();
+
+    blk_inc_in_flight(blk);
+    ret = blk_co_do_preadv_part(blk, offset, bytes, qiov, qiov_offset, flags);
     blk_dec_in_flight(blk);
 
     return ret;
 }
 
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
-int coroutine_fn
+static int coroutine_fn
 blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes,
                        QEMUIOVector *qiov, size_t qiov_offset,
                        BdrvRequestFlags flags)
@@ -1379,6 +1406,17 @@ int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset,
     return ret;
 }
 
+int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
+                               const void *buf, BdrvRequestFlags flags)
+{
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
+    IO_OR_GS_CODE();
+
+    assert(bytes <= SIZE_MAX);
+
+    return blk_co_pwritev(blk, offset, bytes, &qiov, flags);
+}
+
 int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset,
                                 int64_t bytes, QEMUIOVector *qiov,
                                 BdrvRequestFlags flags)
@@ -1387,20 +1425,6 @@ int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset,
     return blk_co_pwritev_part(blk, offset, bytes, qiov, 0, flags);
 }
 
-static int coroutine_fn blk_pwritev_part(BlockBackend *blk, int64_t offset,
-                                         int64_t bytes,
-                                         QEMUIOVector *qiov, size_t qiov_offset,
-                                         BdrvRequestFlags flags)
-{
-    int ret;
-
-    blk_inc_in_flight(blk);
-    ret = blk_do_pwritev_part(blk, offset, bytes, qiov, qiov_offset, flags);
-    blk_dec_in_flight(blk);
-
-    return ret;
-}
-
 typedef struct BlkRwCo {
     BlockBackend *blk;
     int64_t offset;
@@ -1409,14 +1433,6 @@ typedef struct BlkRwCo {
     BdrvRequestFlags flags;
 } BlkRwCo;
 
-int blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
-                      int64_t bytes, BdrvRequestFlags flags)
-{
-    IO_OR_GS_CODE();
-    return blk_pwritev_part(blk, offset, bytes, NULL, 0,
-                            flags | BDRV_REQ_ZERO_WRITE);
-}
-
 int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags)
 {
     GLOBAL_STATE_CODE();
@@ -1537,8 +1553,8 @@ static void blk_aio_read_entry(void *opaque)
     QEMUIOVector *qiov = rwco->iobuf;
 
     assert(qiov->size == acb->bytes);
-    rwco->ret = blk_co_do_preadv(rwco->blk, rwco->offset, acb->bytes,
-                                 qiov, rwco->flags);
+    rwco->ret = blk_co_do_preadv_part(rwco->blk, rwco->offset, acb->bytes, qiov,
+                                      0, rwco->flags);
     blk_aio_complete(acb);
 }
 
@@ -1563,31 +1579,6 @@ BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset,
                         flags | BDRV_REQ_ZERO_WRITE, cb, opaque);
 }
 
-int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int bytes)
-{
-    int ret;
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_OR_GS_CODE();
-
-    blk_inc_in_flight(blk);
-    ret = blk_do_preadv(blk, offset, bytes, &qiov, 0);
-    blk_dec_in_flight(blk);
-
-    return ret < 0 ? ret : bytes;
-}
-
-int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int bytes,
-               BdrvRequestFlags flags)
-{
-    int ret;
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_OR_GS_CODE();
-
-    ret = blk_pwritev_part(blk, offset, bytes, &qiov, 0, flags);
-
-    return ret < 0 ? ret : bytes;
-}
-
 int64_t blk_getlength(BlockBackend *blk)
 {
     IO_CODE();
@@ -1651,7 +1642,7 @@ void blk_aio_cancel_async(BlockAIOCB *acb)
 }
 
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
-int coroutine_fn
+static int coroutine_fn
 blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf)
 {
     IO_CODE();
@@ -1665,13 +1656,14 @@ blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf)
     return bdrv_co_ioctl(blk_bs(blk), req, buf);
 }
 
-int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf)
+int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req,
+                              void *buf)
 {
     int ret;
     IO_OR_GS_CODE();
 
     blk_inc_in_flight(blk);
-    ret = blk_do_ioctl(blk, req, buf);
+    ret = blk_co_do_ioctl(blk, req, buf);
     blk_dec_in_flight(blk);
 
     return ret;
@@ -1695,7 +1687,7 @@ BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
 }
 
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
-int coroutine_fn
+static int coroutine_fn
 blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes)
 {
     int ret;
@@ -1742,20 +1734,8 @@ int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
     return ret;
 }
 
-int blk_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes)
-{
-    int ret;
-    IO_OR_GS_CODE();
-
-    blk_inc_in_flight(blk);
-    ret = blk_do_pdiscard(blk, offset, bytes);
-    blk_dec_in_flight(blk);
-
-    return ret;
-}
-
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
-int coroutine_fn blk_co_do_flush(BlockBackend *blk)
+static int coroutine_fn blk_co_do_flush(BlockBackend *blk)
 {
     blk_wait_while_drained(blk);
     IO_CODE();
@@ -1795,17 +1775,6 @@ int coroutine_fn blk_co_flush(BlockBackend *blk)
     return ret;
 }
 
-int blk_flush(BlockBackend *blk)
-{
-    int ret;
-
-    blk_inc_in_flight(blk);
-    ret = blk_do_flush(blk);
-    blk_dec_in_flight(blk);
-
-    return ret;
-}
-
 void blk_drain(BlockBackend *blk)
 {
     BlockDriverState *bs = blk_bs(blk);
@@ -2337,17 +2306,18 @@ int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
                           flags | BDRV_REQ_ZERO_WRITE);
 }
 
-int blk_pwrite_compressed(BlockBackend *blk, int64_t offset, const void *buf,
-                          int64_t bytes)
+int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset,
+                                          int64_t bytes, const void *buf)
 {
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
     IO_OR_GS_CODE();
-    return blk_pwritev_part(blk, offset, bytes, &qiov, 0,
-                            BDRV_REQ_WRITE_COMPRESSED);
+    return blk_co_pwritev_part(blk, offset, bytes, &qiov, 0,
+                               BDRV_REQ_WRITE_COMPRESSED);
 }
 
-int blk_truncate(BlockBackend *blk, int64_t offset, bool exact,
-                 PreallocMode prealloc, BdrvRequestFlags flags, Error **errp)
+int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact,
+                                 PreallocMode prealloc, BdrvRequestFlags flags,
+                                 Error **errp)
 {
     IO_OR_GS_CODE();
     if (!blk_is_available(blk)) {
@@ -2355,7 +2325,7 @@ int blk_truncate(BlockBackend *blk, int64_t offset, bool exact,
         return -ENOMEDIUM;
     }
 
-    return bdrv_truncate(blk->root, offset, exact, prealloc, flags, errp);
+    return bdrv_co_truncate(blk->root, offset, exact, prealloc, flags, errp);
 }
 
 int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,

block/bochs.c

@@ -116,7 +116,7 @@ static int bochs_open(BlockDriverState *bs, QDict *options, int flags,
         return -EINVAL;
     }
 
-    ret = bdrv_pread(bs->file, 0, &bochs, sizeof(bochs));
+    ret = bdrv_pread(bs->file, 0, sizeof(bochs), &bochs, 0);
     if (ret < 0) {
         return ret;
     }
@@ -150,8 +150,8 @@ static int bochs_open(BlockDriverState *bs, QDict *options, int flags,
         return -ENOMEM;
     }
 
-    ret = bdrv_pread(bs->file, le32_to_cpu(bochs.header), s->catalog_bitmap,
-                     s->catalog_size * 4);
+    ret = bdrv_pread(bs->file, le32_to_cpu(bochs.header), s->catalog_size * 4,
+                     s->catalog_bitmap, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -224,8 +224,8 @@ static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num)
         (s->extent_blocks + s->bitmap_blocks));
 
     /* read in bitmap for current extent */
-    ret = bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8),
-                     &bitmap_entry, 1);
+    ret = bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8), 1,
+                     &bitmap_entry, 0);
     if (ret < 0) {
         return ret;
     }

block/cloop.c

@@ -78,7 +78,7 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
     }
 
     /* read header */
-    ret = bdrv_pread(bs->file, 128, &s->block_size, 4);
+    ret = bdrv_pread(bs->file, 128, 4, &s->block_size, 0);
     if (ret < 0) {
         return ret;
     }
@@ -104,7 +104,7 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
         return -EINVAL;
     }
 
-    ret = bdrv_pread(bs->file, 128 + 4, &s->n_blocks, 4);
+    ret = bdrv_pread(bs->file, 128 + 4, 4, &s->n_blocks, 0);
     if (ret < 0) {
         return ret;
     }
@@ -135,7 +135,7 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
         return -ENOMEM;
     }
 
-    ret = bdrv_pread(bs->file, 128 + 4 + 4, s->offsets, offsets_size);
+    ret = bdrv_pread(bs->file, 128 + 4 + 4, offsets_size, s->offsets, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -220,9 +220,9 @@ static inline int cloop_read_block(BlockDriverState *bs, int block_num)
         int ret;
         uint32_t bytes = s->offsets[block_num + 1] - s->offsets[block_num];
 
-        ret = bdrv_pread(bs->file, s->offsets[block_num],
-                         s->compressed_block, bytes);
-        if (ret != bytes) {
+        ret = bdrv_pread(bs->file, s->offsets[block_num], bytes,
+                         s->compressed_block, 0);
+        if (ret < 0) {
             return -1;
         }
 

block/commit.c

@@ -527,12 +527,12 @@ int bdrv_commit(BlockDriverState *bs)
             goto ro_cleanup;
         }
         if (ret) {
-            ret = blk_pread(src, offset, buf, n);
+            ret = blk_pread(src, offset, n, buf, 0);
             if (ret < 0) {
                 goto ro_cleanup;
             }
 
-            ret = blk_pwrite(backing, offset, buf, n, 0);
+            ret = blk_pwrite(backing, offset, n, buf, 0);
             if (ret < 0) {
                 goto ro_cleanup;
             }

block/coroutines.h

@@ -63,25 +63,6 @@ nbd_co_do_establish_connection(BlockDriverState *bs, bool blocking,
                                Error **errp);
 
 
-int coroutine_fn
-blk_co_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes,
-                 QEMUIOVector *qiov, BdrvRequestFlags flags);
-
-
-int coroutine_fn
-blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes,
-                       QEMUIOVector *qiov, size_t qiov_offset,
-                       BdrvRequestFlags flags);
-
-int coroutine_fn
-blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
-
-int coroutine_fn
-blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes);
-
-int coroutine_fn blk_co_do_flush(BlockBackend *blk);
-
-
 /*
  * "I/O or GS" API functions. These functions can run without
  * the BQL, but only in one specific iothread/main loop.
@@ -90,14 +71,6 @@ int coroutine_fn blk_co_do_flush(BlockBackend *blk);
  * the "I/O or GS" API.
  */
 
-int generated_co_wrapper
-bdrv_preadv(BdrvChild *child, int64_t offset, unsigned int bytes,
-            QEMUIOVector *qiov, BdrvRequestFlags flags);
-
-int generated_co_wrapper
-bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes,
-             QEMUIOVector *qiov, BdrvRequestFlags flags);
-
 int generated_co_wrapper
 bdrv_common_block_status_above(BlockDriverState *bs,
                                BlockDriverState *base,
@@ -112,21 +85,4 @@ bdrv_common_block_status_above(BlockDriverState *bs,
 int generated_co_wrapper
 nbd_do_establish_connection(BlockDriverState *bs, bool blocking, Error **errp);
 
-int generated_co_wrapper
-blk_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes,
-              QEMUIOVector *qiov, BdrvRequestFlags flags);
-
-int generated_co_wrapper
-blk_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes,
-                    QEMUIOVector *qiov, size_t qiov_offset,
-                    BdrvRequestFlags flags);
-
-int generated_co_wrapper
-blk_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
-
-int generated_co_wrapper
-blk_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes);
-
-int generated_co_wrapper blk_do_flush(BlockBackend *blk);
-
 #endif /* BLOCK_COROUTINES_H */

block/crypto.c

@@ -55,40 +55,40 @@ static int block_crypto_probe_generic(QCryptoBlockFormat format,
 }
 
 
-static ssize_t block_crypto_read_func(QCryptoBlock *block,
-                                      size_t offset,
-                                      uint8_t *buf,
-                                      size_t buflen,
-                                      void *opaque,
-                                      Error **errp)
+static int block_crypto_read_func(QCryptoBlock *block,
+                                  size_t offset,
+                                  uint8_t *buf,
+                                  size_t buflen,
+                                  void *opaque,
+                                  Error **errp)
 {
     BlockDriverState *bs = opaque;
     ssize_t ret;
 
-    ret = bdrv_pread(bs->file, offset, buf, buflen);
+    ret = bdrv_pread(bs->file, offset, buflen, buf, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not read encryption header");
         return ret;
     }
-    return ret;
+    return 0;
 }
 
-static ssize_t block_crypto_write_func(QCryptoBlock *block,
-                                       size_t offset,
-                                       const uint8_t *buf,
-                                       size_t buflen,
-                                       void *opaque,
-                                       Error **errp)
+static int block_crypto_write_func(QCryptoBlock *block,
+                                   size_t offset,
+                                   const uint8_t *buf,
+                                   size_t buflen,
+                                   void *opaque,
+                                   Error **errp)
 {
     BlockDriverState *bs = opaque;
     ssize_t ret;
 
-    ret = bdrv_pwrite(bs->file, offset, buf, buflen);
+    ret = bdrv_pwrite(bs->file, offset, buflen, buf, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not write encryption header");
         return ret;
     }
-    return ret;
+    return 0;
 }
 
 
@@ -99,28 +99,28 @@ struct BlockCryptoCreateData {
 };
 
 
-static ssize_t block_crypto_create_write_func(QCryptoBlock *block,
-                                              size_t offset,
-                                              const uint8_t *buf,
-                                              size_t buflen,
-                                              void *opaque,
-                                              Error **errp)
+static int block_crypto_create_write_func(QCryptoBlock *block,
+                                          size_t offset,
+                                          const uint8_t *buf,
+                                          size_t buflen,
+                                          void *opaque,
+                                          Error **errp)
 {
     struct BlockCryptoCreateData *data = opaque;
     ssize_t ret;
 
-    ret = blk_pwrite(data->blk, offset, buf, buflen, 0);
+    ret = blk_pwrite(data->blk, offset, buflen, buf, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not write encryption header");
         return ret;
     }
-    return ret;
+    return 0;
 }
 
-static ssize_t block_crypto_create_init_func(QCryptoBlock *block,
-                                             size_t headerlen,
-                                             void *opaque,
-                                             Error **errp)
+static int block_crypto_create_init_func(QCryptoBlock *block,
+                                         size_t headerlen,
+                                         void *opaque,
+                                         Error **errp)
 {
     struct BlockCryptoCreateData *data = opaque;
     Error *local_error = NULL;
@@ -139,7 +139,7 @@ static ssize_t block_crypto_create_init_func(QCryptoBlock *block,
                        data->prealloc, 0, &local_error);
 
     if (ret >= 0) {
-        return ret;
+        return 0;
     }
 
 error:

block/dmg.c

@@ -77,7 +77,7 @@ static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result)
     uint64_t buffer;
     int ret;
 
-    ret = bdrv_pread(bs->file, offset, &buffer, 8);
+    ret = bdrv_pread(bs->file, offset, 8, &buffer, 0);
     if (ret < 0) {
         return ret;
     }
@@ -91,7 +91,7 @@ static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result)
     uint32_t buffer;
     int ret;
 
-    ret = bdrv_pread(bs->file, offset, &buffer, 4);
+    ret = bdrv_pread(bs->file, offset, 4, &buffer, 0);
     if (ret < 0) {
         return ret;
     }
@@ -172,7 +172,7 @@ static int64_t dmg_find_koly_offset(BdrvChild *file, Error **errp)
         offset = length - 511 - 512;
     }
     length = length < 515 ? length : 515;
-    ret = bdrv_pread(file, offset, buffer, length);
+    ret = bdrv_pread(file, offset, length, buffer, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed while reading UDIF trailer");
         return ret;
@@ -352,7 +352,7 @@ static int dmg_read_resource_fork(BlockDriverState *bs, DmgHeaderState *ds,
         offset += 4;
 
         buffer = g_realloc(buffer, count);
-        ret = bdrv_pread(bs->file, offset, buffer, count);
+        ret = bdrv_pread(bs->file, offset, count, buffer, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -389,8 +389,8 @@ static int dmg_read_plist_xml(BlockDriverState *bs, DmgHeaderState *ds,
 
     buffer = g_malloc(info_length + 1);
     buffer[info_length] = '\0';
-    ret = bdrv_pread(bs->file, info_begin, buffer, info_length);
-    if (ret != info_length) {
+    ret = bdrv_pread(bs->file, info_begin, info_length, buffer, 0);
+    if (ret < 0) {
         ret = -EINVAL;
         goto fail;
     }
@@ -609,9 +609,9 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
         case UDZO: { /* zlib compressed */
             /* we need to buffer, because only the chunk as whole can be
              * inflated. */
-            ret = bdrv_pread(bs->file, s->offsets[chunk],
-                             s->compressed_chunk, s->lengths[chunk]);
-            if (ret != s->lengths[chunk]) {
+            ret = bdrv_pread(bs->file, s->offsets[chunk], s->lengths[chunk],
+                             s->compressed_chunk, 0);
+            if (ret < 0) {
                 return -1;
             }
 
@@ -635,9 +635,9 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
             }
             /* we need to buffer, because only the chunk as whole can be
              * inflated. */
-            ret = bdrv_pread(bs->file, s->offsets[chunk],
-                             s->compressed_chunk, s->lengths[chunk]);
-            if (ret != s->lengths[chunk]) {
+            ret = bdrv_pread(bs->file, s->offsets[chunk], s->lengths[chunk],
+                             s->compressed_chunk, 0);
+            if (ret < 0) {
                 return -1;
             }
 
@@ -656,9 +656,9 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
             }
             /* we need to buffer, because only the chunk as whole can be
              * inflated. */
-            ret = bdrv_pread(bs->file, s->offsets[chunk],
-                             s->compressed_chunk, s->lengths[chunk]);
-            if (ret != s->lengths[chunk]) {
+            ret = bdrv_pread(bs->file, s->offsets[chunk], s->lengths[chunk],
+                             s->compressed_chunk, 0);
+            if (ret < 0) {
                 return -1;
             }
 
@@ -672,9 +672,9 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
             }
             break;
         case UDRW: /* copy */
-            ret = bdrv_pread(bs->file, s->offsets[chunk],
-                             s->uncompressed_chunk, s->lengths[chunk]);
-            if (ret != s->lengths[chunk]) {
+            ret = bdrv_pread(bs->file, s->offsets[chunk], s->lengths[chunk],
+                             s->uncompressed_chunk, 0);
+            if (ret < 0) {
                 return -1;
             }
             break;

block/export/fuse.c

@@ -554,7 +554,7 @@ static void fuse_read(fuse_req_t req, fuse_ino_t inode,
         return;
     }
 
-    ret = blk_pread(exp->common.blk, offset, buf, size);
+    ret = blk_pread(exp->common.blk, offset, size, buf, 0);
     if (ret >= 0) {
         fuse_reply_buf(req, buf, size);
     } else {
@@ -607,7 +607,7 @@ static void fuse_write(fuse_req_t req, fuse_ino_t inode, const char *buf,
         }
     }
 
-    ret = blk_pwrite(exp->common.blk, offset, buf, size, 0);
+    ret = blk_pwrite(exp->common.blk, offset, size, buf, 0);
     if (ret >= 0) {
         fuse_reply_write(req, size);
     } else {

block/io.c

@@ -1046,14 +1046,6 @@ static int bdrv_check_request32(int64_t offset, int64_t bytes,
     return 0;
 }
 
-int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
-                       int64_t bytes, BdrvRequestFlags flags)
-{
-    IO_CODE();
-    return bdrv_pwritev(child, offset, bytes, NULL,
-                        BDRV_REQ_ZERO_WRITE | flags);
-}
-
 /*
  * Completely zero out a block device with the help of bdrv_pwrite_zeroes.
  * The operation is sped up by checking the block status and only writing
@@ -1096,62 +1088,25 @@ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
     }
 }
 
-/* See bdrv_pwrite() for the return codes */
-int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int64_t bytes)
-{
-    int ret;
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_CODE();
-
-    if (bytes < 0) {
-        return -EINVAL;
-    }
-
-    ret = bdrv_preadv(child, offset, bytes, &qiov,  0);
-
-    return ret < 0 ? ret : bytes;
-}
-
-/* Return no. of bytes on success or < 0 on error. Important errors are:
-  -EIO         generic I/O error (may happen for all errors)
-  -ENOMEDIUM   No media inserted.
-  -EINVAL      Invalid offset or number of bytes
-  -EACCES      Trying to write a read-only device
-*/
-int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf,
-                int64_t bytes)
-{
-    int ret;
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_CODE();
-
-    if (bytes < 0) {
-        return -EINVAL;
-    }
-
-    ret = bdrv_pwritev(child, offset, bytes, &qiov, 0);
-
-    return ret < 0 ? ret : bytes;
-}
-
 /*
  * Writes to the file and ensures that no writes are reordered across this
  * request (acts as a barrier)
  *
  * Returns 0 on success, -errno in error cases.
  */
-int bdrv_pwrite_sync(BdrvChild *child, int64_t offset,
-                     const void *buf, int64_t count)
+int coroutine_fn bdrv_co_pwrite_sync(BdrvChild *child, int64_t offset,
+                                     int64_t bytes, const void *buf,
+                                     BdrvRequestFlags flags)
 {
     int ret;
     IO_CODE();
 
-    ret = bdrv_pwrite(child, offset, buf, count);
+    ret = bdrv_co_pwrite(child, offset, bytes, buf, flags);
     if (ret < 0) {
         return ret;
     }
 
-    ret = bdrv_flush(child->bs);
+    ret = bdrv_co_flush(child->bs);
     if (ret < 0) {
         return ret;
     }

block/meson.build

@@ -136,6 +136,7 @@ block_gen_c = custom_target('block-gen.c',
                             input: files(
                                       '../include/block/block-io.h',
                                       '../include/block/block-global-state.h',
+                                      '../include/sysemu/block-backend-io.h',
                                       'coroutines.h'
                                       ),
                             command: [wrapper_py, '@OUTPUT@', '@INPUT@'])

block/parallels-ext.c

@@ -93,8 +93,8 @@ static int parallels_load_bitmap_data(BlockDriverState *bs,
         if (entry == 1) {
             bdrv_dirty_bitmap_deserialize_ones(bitmap, offset, count, false);
         } else {
-            ret = bdrv_pread(bs->file, entry << BDRV_SECTOR_BITS, buf,
-                             s->cluster_size);
+            ret = bdrv_pread(bs->file, entry << BDRV_SECTOR_BITS,
+                             s->cluster_size, buf, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret,
                                  "Failed to read bitmap data cluster");
@@ -286,7 +286,7 @@ int parallels_read_format_extension(BlockDriverState *bs,
 
     assert(ext_off > 0);
 
-    ret = bdrv_pread(bs->file, ext_off, ext_cluster, s->cluster_size);
+    ret = bdrv_pread(bs->file, ext_off, s->cluster_size, ext_cluster, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to read Format Extension cluster");
         goto out;

block/parallels.c

@@ -277,8 +277,8 @@ static coroutine_fn int parallels_co_flush_to_os(BlockDriverState *bs)
         if (off + to_write > s->header_size) {
             to_write = s->header_size - off;
         }
-        ret = bdrv_pwrite(bs->file, off, (uint8_t *)s->header + off,
-                          to_write);
+        ret = bdrv_pwrite(bs->file, off, to_write, (uint8_t *)s->header + off,
+                          0);
         if (ret < 0) {
             qemu_co_mutex_unlock(&s->lock);
             return ret;
@@ -481,7 +481,7 @@ static int coroutine_fn parallels_co_check(BlockDriverState *bs,
 
     ret = 0;
     if (flush_bat) {
-        ret = bdrv_pwrite_sync(bs->file, 0, s->header, s->header_size);
+        ret = bdrv_co_pwrite_sync(bs->file, 0, s->header_size, s->header, 0);
         if (ret < 0) {
             res->check_errors++;
             goto out;
@@ -599,7 +599,7 @@ static int coroutine_fn parallels_co_create(BlockdevCreateOptions* opts,
     memset(tmp, 0, sizeof(tmp));
     memcpy(tmp, &header, sizeof(header));
 
-    ret = blk_pwrite(blk, 0, tmp, BDRV_SECTOR_SIZE, 0);
+    ret = blk_pwrite(blk, 0, BDRV_SECTOR_SIZE, tmp, 0);
     if (ret < 0) {
         goto exit;
     }
@@ -723,7 +723,7 @@ static int parallels_update_header(BlockDriverState *bs)
     if (size > s->header_size) {
         size = s->header_size;
     }
-    return bdrv_pwrite_sync(bs->file, 0, s->header, size);
+    return bdrv_pwrite_sync(bs->file, 0, size, s->header, 0);
 }
 
 static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
@@ -742,7 +742,7 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
         return -EINVAL;
     }
 
-    ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
+    ret = bdrv_pread(bs->file, 0, sizeof(ph), &ph, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -798,7 +798,7 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
         s->header_size = size;
     }
 
-    ret = bdrv_pread(bs->file, 0, s->header, s->header_size);
+    ret = bdrv_pread(bs->file, 0, s->header_size, s->header, 0);
     if (ret < 0) {
         goto fail;
     }

block/qcow.c

@@ -128,7 +128,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
+    ret = bdrv_pread(bs->file, 0, sizeof(header), &header, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -260,8 +260,8 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
-               s->l1_size * sizeof(uint64_t));
+    ret = bdrv_pread(bs->file, s->l1_table_offset,
+                     s->l1_size * sizeof(uint64_t), s->l1_table, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -291,8 +291,8 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
             ret = -EINVAL;
             goto fail;
         }
-        ret = bdrv_pread(bs->file, header.backing_file_offset,
-                   bs->auto_backing_file, len);
+        ret = bdrv_pread(bs->file, header.backing_file_offset, len,
+                         bs->auto_backing_file, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -383,7 +383,7 @@ static int get_cluster_offset(BlockDriverState *bs,
         BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE);
         ret = bdrv_pwrite_sync(bs->file,
                                s->l1_table_offset + l1_index * sizeof(tmp),
-                               &tmp, sizeof(tmp));
+                               sizeof(tmp), &tmp, 0);
         if (ret < 0) {
             return ret;
         }
@@ -414,14 +414,14 @@ static int get_cluster_offset(BlockDriverState *bs,
     BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD);
     if (new_l2_table) {
         memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
-        ret = bdrv_pwrite_sync(bs->file, l2_offset, l2_table,
-                               s->l2_size * sizeof(uint64_t));
+        ret = bdrv_pwrite_sync(bs->file, l2_offset,
+                               s->l2_size * sizeof(uint64_t), l2_table, 0);
         if (ret < 0) {
             return ret;
         }
     } else {
-        ret = bdrv_pread(bs->file, l2_offset, l2_table,
-                         s->l2_size * sizeof(uint64_t));
+        ret = bdrv_pread(bs->file, l2_offset, s->l2_size * sizeof(uint64_t),
+                         l2_table, 0);
         if (ret < 0) {
             return ret;
         }
@@ -453,8 +453,8 @@ static int get_cluster_offset(BlockDriverState *bs,
             cluster_offset = QEMU_ALIGN_UP(cluster_offset, s->cluster_size);
             /* write the cluster content */
             BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
-            ret = bdrv_pwrite(bs->file, cluster_offset, s->cluster_cache,
-                              s->cluster_size);
+            ret = bdrv_pwrite(bs->file, cluster_offset, s->cluster_size,
+                              s->cluster_cache, 0);
             if (ret < 0) {
                 return ret;
             }
@@ -492,10 +492,9 @@ static int get_cluster_offset(BlockDriverState *bs,
                                 return -EIO;
                             }
                             BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
-                            ret = bdrv_pwrite(bs->file,
-                                              cluster_offset + i,
-                                              s->cluster_data,
-                                              BDRV_SECTOR_SIZE);
+                            ret = bdrv_pwrite(bs->file, cluster_offset + i,
+                                              BDRV_SECTOR_SIZE,
+                                              s->cluster_data, 0);
                             if (ret < 0) {
                                 return ret;
                             }
@@ -516,7 +515,7 @@ static int get_cluster_offset(BlockDriverState *bs,
             BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE);
         }
         ret = bdrv_pwrite_sync(bs->file, l2_offset + l2_index * sizeof(tmp),
-                               &tmp, sizeof(tmp));
+                               sizeof(tmp), &tmp, 0);
         if (ret < 0) {
             return ret;
         }
@@ -597,8 +596,8 @@ static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
         csize = cluster_offset >> (63 - s->cluster_bits);
         csize &= (s->cluster_size - 1);
         BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED);
-        ret = bdrv_pread(bs->file, coffset, s->cluster_data, csize);
-        if (ret != csize)
+        ret = bdrv_pread(bs->file, coffset, csize, s->cluster_data, 0);
+        if (ret < 0)
             return -1;
         if (decompress_buffer(s->cluster_cache, s->cluster_size,
                               s->cluster_data, csize) < 0) {
@@ -891,15 +890,15 @@ static int coroutine_fn qcow_co_create(BlockdevCreateOptions *opts,
     }
 
     /* write all the data */
-    ret = blk_pwrite(qcow_blk, 0, &header, sizeof(header), 0);
-    if (ret != sizeof(header)) {
+    ret = blk_pwrite(qcow_blk, 0, sizeof(header), &header, 0);
+    if (ret < 0) {
         goto exit;
     }
 
     if (qcow_opts->has_backing_file) {
-        ret = blk_pwrite(qcow_blk, sizeof(header),
-                         qcow_opts->backing_file, backing_filename_len, 0);
-        if (ret != backing_filename_len) {
+        ret = blk_pwrite(qcow_blk, sizeof(header), backing_filename_len,
+                         qcow_opts->backing_file, 0);
+        if (ret < 0) {
             goto exit;
         }
     }
@@ -908,8 +907,8 @@ static int coroutine_fn qcow_co_create(BlockdevCreateOptions *opts,
     for (i = 0; i < DIV_ROUND_UP(sizeof(uint64_t) * l1_size, BDRV_SECTOR_SIZE);
          i++) {
         ret = blk_pwrite(qcow_blk, header_size + BDRV_SECTOR_SIZE * i,
-                         tmp, BDRV_SECTOR_SIZE, 0);
-        if (ret != BDRV_SECTOR_SIZE) {
+                         BDRV_SECTOR_SIZE, tmp, 0);
+        if (ret < 0) {
             g_free(tmp);
             goto exit;
         }
@@ -1030,8 +1029,8 @@ static int qcow_make_empty(BlockDriverState *bs)
     int ret;
 
     memset(s->l1_table, 0, l1_length);
-    if (bdrv_pwrite_sync(bs->file, s->l1_table_offset, s->l1_table,
-            l1_length) < 0)
+    if (bdrv_pwrite_sync(bs->file, s->l1_table_offset, l1_length, s->l1_table,
+                         0) < 0)
         return -1;
     ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length, false,
                         PREALLOC_MODE_OFF, 0, NULL);

block/qcow2-bitmap.c

@@ -234,8 +234,8 @@ static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb,
     }
 
     assert(tb->size <= BME_MAX_TABLE_SIZE);
-    ret = bdrv_pread(bs->file, tb->offset,
-                     table, tb->size * BME_TABLE_ENTRY_SIZE);
+    ret = bdrv_pread(bs->file, tb->offset, tb->size * BME_TABLE_ENTRY_SIZE,
+                     table, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -317,7 +317,7 @@ static int load_bitmap_data(BlockDriverState *bs,
                  * already cleared */
             }
         } else {
-            ret = bdrv_pread(bs->file, data_offset, buf, s->cluster_size);
+            ret = bdrv_pread(bs->file, data_offset, s->cluster_size, buf, 0);
             if (ret < 0) {
                 goto finish;
             }
@@ -575,7 +575,7 @@ static Qcow2BitmapList *bitmap_list_load(BlockDriverState *bs, uint64_t offset,
     }
     dir_end = dir + size;
 
-    ret = bdrv_pread(bs->file, offset, dir, size);
+    ret = bdrv_pread(bs->file, offset, size, dir, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to read bitmap directory");
         goto fail;
@@ -798,7 +798,7 @@ static int bitmap_list_store(BlockDriverState *bs, Qcow2BitmapList *bm_list,
         goto fail;
     }
 
-    ret = bdrv_pwrite(bs->file, dir_offset, dir, dir_size);
+    ret = bdrv_pwrite(bs->file, dir_offset, dir_size, dir, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -1339,7 +1339,7 @@ static uint64_t *store_bitmap_data(BlockDriverState *bs,
             goto fail;
         }
 
-        ret = bdrv_pwrite(bs->file, off, buf, s->cluster_size);
+        ret = bdrv_pwrite(bs->file, off, s->cluster_size, buf, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file",
                              bm_name);
@@ -1402,7 +1402,7 @@ static int store_bitmap(BlockDriverState *bs, Qcow2Bitmap *bm, Error **errp)
     }
 
     bitmap_table_to_be(tb, tb_size);
-    ret = bdrv_pwrite(bs->file, tb_offset, tb, tb_size * sizeof(tb[0]));
+    ret = bdrv_pwrite(bs->file, tb_offset, tb_size * sizeof(tb[0]), tb, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file",
                          bm_name);

block/qcow2-cache.c

@@ -223,8 +223,8 @@ static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
         BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE);
     }
 
-    ret = bdrv_pwrite(bs->file, c->entries[i].offset,
-                      qcow2_cache_get_table_addr(c, i), c->table_size);
+    ret = bdrv_pwrite(bs->file, c->entries[i].offset, c->table_size,
+                      qcow2_cache_get_table_addr(c, i), 0);
     if (ret < 0) {
         return ret;
     }
@@ -379,9 +379,8 @@ static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
             BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD);
         }
 
-        ret = bdrv_pread(bs->file, offset,
-                         qcow2_cache_get_table_addr(c, i),
-                         c->table_size);
+        ret = bdrv_pread(bs->file, offset, c->table_size,
+                         qcow2_cache_get_table_addr(c, i), 0);
         if (ret < 0) {
             return ret;
         }

block/qcow2-cluster.c

@@ -159,8 +159,8 @@ int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
     BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_WRITE_TABLE);
     for(i = 0; i < s->l1_size; i++)
         new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
-    ret = bdrv_pwrite_sync(bs->file, new_l1_table_offset,
-                           new_l1_table, new_l1_size2);
+    ret = bdrv_pwrite_sync(bs->file, new_l1_table_offset, new_l1_size2,
+                           new_l1_table, 0);
     if (ret < 0)
         goto fail;
     for(i = 0; i < s->l1_size; i++)
@@ -171,7 +171,7 @@ int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
     stl_be_p(data, new_l1_size);
     stq_be_p(data + 4, new_l1_table_offset);
     ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, l1_size),
-                           data, sizeof(data));
+                           sizeof(data), data, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -249,7 +249,7 @@ int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index)
     BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE);
     ret = bdrv_pwrite_sync(bs->file,
                            s->l1_table_offset + L1E_SIZE * l1_start_index,
-                           buf, bufsize);
+                           bufsize, buf, 0);
     if (ret < 0) {
         return ret;
     }
@@ -2260,7 +2260,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
                                       (void **)&l2_slice);
             } else {
                 /* load inactive L2 tables from disk */
-                ret = bdrv_pread(bs->file, slice_offset, l2_slice, slice_size2);
+                ret = bdrv_pread(bs->file, slice_offset, slice_size2,
+                                 l2_slice, 0);
             }
             if (ret < 0) {
                 goto fail;
@@ -2376,8 +2377,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
                         goto fail;
                     }
 
-                    ret = bdrv_pwrite(bs->file, slice_offset,
-                                      l2_slice, slice_size2);
+                    ret = bdrv_pwrite(bs->file, slice_offset, slice_size2,
+                                      l2_slice, 0);
                     if (ret < 0) {
                         goto fail;
                     }
@@ -2470,8 +2471,8 @@ int qcow2_expand_zero_clusters(BlockDriverState *bs,
 
         l1_table = new_l1_table;
 
-        ret = bdrv_pread(bs->file, s->snapshots[i].l1_table_offset,
-                         l1_table, l1_size2);
+        ret = bdrv_pread(bs->file, s->snapshots[i].l1_table_offset, l1_size2,
+                         l1_table, 0);
         if (ret < 0) {
             goto fail;
         }

block/qcow2-refcount.c

@@ -119,7 +119,7 @@ int qcow2_refcount_init(BlockDriverState *bs)
         }
         BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD);
         ret = bdrv_pread(bs->file, s->refcount_table_offset,
-                         s->refcount_table, refcount_table_size2);
+                         refcount_table_size2, s->refcount_table, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -439,7 +439,7 @@ static int alloc_refcount_block(BlockDriverState *bs,
         BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP);
         ret = bdrv_pwrite_sync(bs->file, s->refcount_table_offset +
                                refcount_table_index * REFTABLE_ENTRY_SIZE,
-            &data64, sizeof(data64));
+            sizeof(data64), &data64, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -684,8 +684,8 @@ int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t start_offset,
     }
 
     BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE);
-    ret = bdrv_pwrite_sync(bs->file, table_offset, new_table,
-        table_size * REFTABLE_ENTRY_SIZE);
+    ret = bdrv_pwrite_sync(bs->file, table_offset,
+                           table_size * REFTABLE_ENTRY_SIZE, new_table, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -704,7 +704,7 @@ int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t start_offset,
     BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE);
     ret = bdrv_pwrite_sync(bs->file,
                            offsetof(QCowHeader, refcount_table_offset),
-                           &data, sizeof(data));
+                           sizeof(data), &data, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -1274,7 +1274,7 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
         }
         l1_allocated = true;
 
-        ret = bdrv_pread(bs->file, l1_table_offset, l1_table, l1_size2);
+        ret = bdrv_pread(bs->file, l1_table_offset, l1_size2, l1_table, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -1435,8 +1435,8 @@ fail:
             cpu_to_be64s(&l1_table[i]);
         }
 
-        ret = bdrv_pwrite_sync(bs->file, l1_table_offset,
-                               l1_table, l1_size2);
+        ret = bdrv_pwrite_sync(bs->file, l1_table_offset, l1_size2, l1_table,
+                               0);
 
         for (i = 0; i < l1_size; i++) {
             be64_to_cpus(&l1_table[i]);
@@ -1633,8 +1633,8 @@ static int fix_l2_entry_by_zero(BlockDriverState *bs, BdrvCheckResult *res,
         goto fail;
     }
 
-    ret = bdrv_pwrite_sync(bs->file, l2e_offset, &l2_table[idx],
-                           l2_entry_size(s));
+    ret = bdrv_pwrite_sync(bs->file, l2e_offset, l2_entry_size(s),
+                           &l2_table[idx], 0);
     if (ret < 0) {
         fprintf(stderr, "ERROR: Failed to overwrite L2 "
                 "table entry: %s\n", strerror(-ret));
@@ -1672,7 +1672,7 @@ static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
     bool metadata_overlap;
 
     /* Read L2 table from disk */
-    ret = bdrv_pread(bs->file, l2_offset, l2_table, l2_size_bytes);
+    ret = bdrv_pread(bs->file, l2_offset, l2_size_bytes, l2_table, 0);
     if (ret < 0) {
         fprintf(stderr, "ERROR: I/O error in check_refcounts_l2\n");
         res->check_errors++;
@@ -1888,7 +1888,7 @@ static int check_refcounts_l1(BlockDriverState *bs,
     }
 
     /* Read L1 table entries from disk */
-    ret = bdrv_pread(bs->file, l1_table_offset, l1_table, l1_size_bytes);
+    ret = bdrv_pread(bs->file, l1_table_offset, l1_size_bytes, l1_table, 0);
     if (ret < 0) {
         fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
         res->check_errors++;
@@ -2004,8 +2004,8 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res,
             }
         }
 
-        ret = bdrv_pread(bs->file, l2_offset, l2_table,
-                         s->l2_size * l2_entry_size(s));
+        ret = bdrv_pread(bs->file, l2_offset, s->l2_size * l2_entry_size(s),
+                         l2_table, 0);
         if (ret < 0) {
             fprintf(stderr, "ERROR: Could not read L2 table: %s\n",
                     strerror(-ret));
@@ -2058,8 +2058,8 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res,
                 goto fail;
             }
 
-            ret = bdrv_pwrite(bs->file, l2_offset, l2_table,
-                              s->cluster_size);
+            ret = bdrv_pwrite(bs->file, l2_offset, s->cluster_size, l2_table,
+                              0);
             if (ret < 0) {
                 fprintf(stderr, "ERROR: Could not write L2 table: %s\n",
                         strerror(-ret));
@@ -2577,8 +2577,8 @@ static int rebuild_refcounts_write_refblocks(
         on_disk_refblock = (void *)((char *) *refcount_table +
                                     refblock_index * s->cluster_size);
 
-        ret = bdrv_pwrite(bs->file, refblock_offset, on_disk_refblock,
-                          s->cluster_size);
+        ret = bdrv_pwrite(bs->file, refblock_offset, s->cluster_size,
+                          on_disk_refblock, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "ERROR writing refblock");
             return ret;
@@ -2733,8 +2733,8 @@ static int rebuild_refcount_structure(BlockDriverState *bs,
     }
 
     assert(reftable_length < INT_MAX);
-    ret = bdrv_pwrite(bs->file, reftable_offset, on_disk_reftable,
-                      reftable_length);
+    ret = bdrv_pwrite(bs->file, reftable_offset, reftable_length,
+                      on_disk_reftable, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "ERROR writing reftable");
         goto fail;
@@ -2746,8 +2746,8 @@ static int rebuild_refcount_structure(BlockDriverState *bs,
         cpu_to_be32(reftable_clusters);
     ret = bdrv_pwrite_sync(bs->file,
                            offsetof(QCowHeader, refcount_table_offset),
-                           &reftable_offset_and_clusters,
-                           sizeof(reftable_offset_and_clusters));
+                           sizeof(reftable_offset_and_clusters),
+                           &reftable_offset_and_clusters, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "ERROR setting reftable");
         goto fail;
@@ -3009,7 +3009,7 @@ int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
                 return -ENOMEM;
             }
 
-            ret = bdrv_pread(bs->file, l1_ofs, l1, l1_sz2);
+            ret = bdrv_pread(bs->file, l1_ofs, l1_sz2, l1, 0);
             if (ret < 0) {
                 g_free(l1);
                 return ret;
@@ -3180,7 +3180,7 @@ static int flush_refblock(BlockDriverState *bs, uint64_t **reftable,
             return ret;
         }
 
-        ret = bdrv_pwrite(bs->file, offset, refblock, s->cluster_size);
+        ret = bdrv_pwrite(bs->file, offset, s->cluster_size, refblock, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to write refblock");
             return ret;
@@ -3452,8 +3452,9 @@ int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
         cpu_to_be64s(&new_reftable[i]);
     }
 
-    ret = bdrv_pwrite(bs->file, new_reftable_offset, new_reftable,
-                      new_reftable_size * REFTABLE_ENTRY_SIZE);
+    ret = bdrv_pwrite(bs->file, new_reftable_offset,
+                      new_reftable_size * REFTABLE_ENTRY_SIZE, new_reftable,
+                      0);
 
     for (i = 0; i < new_reftable_size; i++) {
         be64_to_cpus(&new_reftable[i]);
@@ -3656,8 +3657,9 @@ int qcow2_shrink_reftable(BlockDriverState *bs)
         reftable_tmp[i] = unused_block ? 0 : cpu_to_be64(s->refcount_table[i]);
     }
 
-    ret = bdrv_pwrite_sync(bs->file, s->refcount_table_offset, reftable_tmp,
-                           s->refcount_table_size * REFTABLE_ENTRY_SIZE);
+    ret = bdrv_pwrite_sync(bs->file, s->refcount_table_offset,
+                           s->refcount_table_size * REFTABLE_ENTRY_SIZE,
+                           reftable_tmp, 0);
     /*
      * If the write in the reftable failed the image may contain a partially
      * overwritten reftable. In this case it would be better to clear the

block/qcow2-snapshot.c

@@ -108,7 +108,7 @@ static int qcow2_do_read_snapshots(BlockDriverState *bs, bool repair,
 
         /* Read statically sized part of the snapshot header */
         offset = ROUND_UP(offset, 8);
-        ret = bdrv_pread(bs->file, offset, &h, sizeof(h));
+        ret = bdrv_pread(bs->file, offset, sizeof(h), &h, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to read snapshot table");
             goto fail;
@@ -146,8 +146,8 @@ static int qcow2_do_read_snapshots(BlockDriverState *bs, bool repair,
         }
 
         /* Read known extra data */
-        ret = bdrv_pread(bs->file, offset, &extra,
-                         MIN(sizeof(extra), sn->extra_data_size));
+        ret = bdrv_pread(bs->file, offset,
+                         MIN(sizeof(extra), sn->extra_data_size), &extra, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to read snapshot table");
             goto fail;
@@ -184,8 +184,8 @@ static int qcow2_do_read_snapshots(BlockDriverState *bs, bool repair,
             /* Store unknown extra data */
             unknown_extra_data_size = sn->extra_data_size - sizeof(extra);
             sn->unknown_extra_data = g_malloc(unknown_extra_data_size);
-            ret = bdrv_pread(bs->file, offset, sn->unknown_extra_data,
-                             unknown_extra_data_size);
+            ret = bdrv_pread(bs->file, offset, unknown_extra_data_size,
+                             sn->unknown_extra_data, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret,
                                  "Failed to read snapshot table");
@@ -196,7 +196,7 @@ static int qcow2_do_read_snapshots(BlockDriverState *bs, bool repair,
 
         /* Read snapshot ID */
         sn->id_str = g_malloc(id_str_size + 1);
-        ret = bdrv_pread(bs->file, offset, sn->id_str, id_str_size);
+        ret = bdrv_pread(bs->file, offset, id_str_size, sn->id_str, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to read snapshot table");
             goto fail;
@@ -206,7 +206,7 @@ static int qcow2_do_read_snapshots(BlockDriverState *bs, bool repair,
 
         /* Read snapshot name */
         sn->name = g_malloc(name_size + 1);
-        ret = bdrv_pread(bs->file, offset, sn->name, name_size);
+        ret = bdrv_pread(bs->file, offset, name_size, sn->name, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to read snapshot table");
             goto fail;
@@ -349,13 +349,13 @@ int qcow2_write_snapshots(BlockDriverState *bs)
         h.name_size = cpu_to_be16(name_size);
         offset = ROUND_UP(offset, 8);
 
-        ret = bdrv_pwrite(bs->file, offset, &h, sizeof(h));
+        ret = bdrv_pwrite(bs->file, offset, sizeof(h), &h, 0);
         if (ret < 0) {
             goto fail;
         }
         offset += sizeof(h);
 
-        ret = bdrv_pwrite(bs->file, offset, &extra, sizeof(extra));
+        ret = bdrv_pwrite(bs->file, offset, sizeof(extra), &extra, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -369,21 +369,21 @@ int qcow2_write_snapshots(BlockDriverState *bs)
             assert(unknown_extra_data_size <= BDRV_REQUEST_MAX_BYTES);
             assert(sn->unknown_extra_data);
 
-            ret = bdrv_pwrite(bs->file, offset, sn->unknown_extra_data,
-                              unknown_extra_data_size);
+            ret = bdrv_pwrite(bs->file, offset, unknown_extra_data_size,
+                              sn->unknown_extra_data, 0);
             if (ret < 0) {
                 goto fail;
             }
             offset += unknown_extra_data_size;
         }
 
-        ret = bdrv_pwrite(bs->file, offset, sn->id_str, id_str_size);
+        ret = bdrv_pwrite(bs->file, offset, id_str_size, sn->id_str, 0);
         if (ret < 0) {
             goto fail;
         }
         offset += id_str_size;
 
-        ret = bdrv_pwrite(bs->file, offset, sn->name, name_size);
+        ret = bdrv_pwrite(bs->file, offset, name_size, sn->name, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -406,7 +406,7 @@ int qcow2_write_snapshots(BlockDriverState *bs)
     header_data.snapshots_offset    = cpu_to_be64(snapshots_offset);
 
     ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, nb_snapshots),
-                           &header_data, sizeof(header_data));
+                           sizeof(header_data), &header_data, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -442,7 +442,8 @@ int coroutine_fn qcow2_check_read_snapshot_table(BlockDriverState *bs,
 
     /* qcow2_do_open() discards this information in check mode */
     ret = bdrv_pread(bs->file, offsetof(QCowHeader, nb_snapshots),
-                     &snapshot_table_pointer, sizeof(snapshot_table_pointer));
+                     sizeof(snapshot_table_pointer), &snapshot_table_pointer,
+                     0);
     if (ret < 0) {
         result->check_errors++;
         fprintf(stderr, "ERROR failed to read the snapshot table pointer from "
@@ -511,9 +512,9 @@ int coroutine_fn qcow2_check_read_snapshot_table(BlockDriverState *bs,
         assert(fix & BDRV_FIX_ERRORS);
 
         snapshot_table_pointer.nb_snapshots = cpu_to_be32(s->nb_snapshots);
-        ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, nb_snapshots),
-                               &snapshot_table_pointer.nb_snapshots,
-                               sizeof(snapshot_table_pointer.nb_snapshots));
+        ret = bdrv_co_pwrite_sync(bs->file, offsetof(QCowHeader, nb_snapshots),
+                                  sizeof(snapshot_table_pointer.nb_snapshots),
+                                  &snapshot_table_pointer.nb_snapshots, 0);
         if (ret < 0) {
             result->check_errors++;
             fprintf(stderr, "ERROR failed to update the snapshot count in the "
@@ -693,8 +694,8 @@ int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
         goto fail;
     }
 
-    ret = bdrv_pwrite(bs->file, sn->l1_table_offset, l1_table,
-                      s->l1_size * L1E_SIZE);
+    ret = bdrv_pwrite(bs->file, sn->l1_table_offset, s->l1_size * L1E_SIZE,
+                      l1_table, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -829,8 +830,8 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
         goto fail;
     }
 
-    ret = bdrv_pread(bs->file, sn->l1_table_offset,
-                     sn_l1_table, sn_l1_bytes);
+    ret = bdrv_pread(bs->file, sn->l1_table_offset, sn_l1_bytes, sn_l1_table,
+                     0);
     if (ret < 0) {
         goto fail;
     }
@@ -848,8 +849,8 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
         goto fail;
     }
 
-    ret = bdrv_pwrite_sync(bs->file, s->l1_table_offset, sn_l1_table,
-                           cur_l1_bytes);
+    ret = bdrv_pwrite_sync(bs->file, s->l1_table_offset, cur_l1_bytes,
+                           sn_l1_table, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -1051,8 +1052,8 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs,
         return -ENOMEM;
     }
 
-    ret = bdrv_pread(bs->file, sn->l1_table_offset,
-                     new_l1_table, new_l1_bytes);
+    ret = bdrv_pread(bs->file, sn->l1_table_offset, new_l1_bytes,
+                     new_l1_table, 0);
     if (ret < 0) {
         error_setg(errp, "Failed to read l1 table for snapshot");
         qemu_vfree(new_l1_table);

block/qcow2.c

@@ -94,9 +94,9 @@ static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename)
 }
 
 
-static ssize_t qcow2_crypto_hdr_read_func(QCryptoBlock *block, size_t offset,
-                                          uint8_t *buf, size_t buflen,
-                                          void *opaque, Error **errp)
+static int qcow2_crypto_hdr_read_func(QCryptoBlock *block, size_t offset,
+                                      uint8_t *buf, size_t buflen,
+                                      void *opaque, Error **errp)
 {
     BlockDriverState *bs = opaque;
     BDRVQcow2State *s = bs->opaque;
@@ -107,18 +107,18 @@ static ssize_t qcow2_crypto_hdr_read_func(QCryptoBlock *block, size_t offset,
         return -1;
     }
 
-    ret = bdrv_pread(bs->file,
-                     s->crypto_header.offset + offset, buf, buflen);
+    ret = bdrv_pread(bs->file, s->crypto_header.offset + offset, buflen, buf,
+                     0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not read encryption header");
         return -1;
     }
-    return ret;
+    return 0;
 }
 
 
-static ssize_t qcow2_crypto_hdr_init_func(QCryptoBlock *block, size_t headerlen,
-                                          void *opaque, Error **errp)
+static int qcow2_crypto_hdr_init_func(QCryptoBlock *block, size_t headerlen,
+                                      void *opaque, Error **errp)
 {
     BlockDriverState *bs = opaque;
     BDRVQcow2State *s = bs->opaque;
@@ -151,13 +151,13 @@ static ssize_t qcow2_crypto_hdr_init_func(QCryptoBlock *block, size_t headerlen,
         return -1;
     }
 
-    return ret;
+    return 0;
 }
 
 
-static ssize_t qcow2_crypto_hdr_write_func(QCryptoBlock *block, size_t offset,
-                                           const uint8_t *buf, size_t buflen,
-                                           void *opaque, Error **errp)
+static int qcow2_crypto_hdr_write_func(QCryptoBlock *block, size_t offset,
+                                       const uint8_t *buf, size_t buflen,
+                                       void *opaque, Error **errp)
 {
     BlockDriverState *bs = opaque;
     BDRVQcow2State *s = bs->opaque;
@@ -168,13 +168,13 @@ static ssize_t qcow2_crypto_hdr_write_func(QCryptoBlock *block, size_t offset,
         return -1;
     }
 
-    ret = bdrv_pwrite(bs->file,
-                      s->crypto_header.offset + offset, buf, buflen);
+    ret = bdrv_pwrite(bs->file, s->crypto_header.offset + offset, buflen, buf,
+                      0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not read encryption header");
         return -1;
     }
-    return ret;
+    return 0;
 }
 
 static QDict*
@@ -227,7 +227,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
         printf("attempting to read extended header in offset %lu\n", offset);
 #endif
 
-        ret = bdrv_pread(bs->file, offset, &ext, sizeof(ext));
+        ret = bdrv_pread(bs->file, offset, sizeof(ext), &ext, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "qcow2_read_extension: ERROR: "
                              "pread fail from offset %" PRIu64, offset);
@@ -255,7 +255,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
                            sizeof(bs->backing_format));
                 return 2;
             }
-            ret = bdrv_pread(bs->file, offset, bs->backing_format, ext.len);
+            ret = bdrv_pread(bs->file, offset, ext.len, bs->backing_format, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret, "ERROR: ext_backing_format: "
                                  "Could not read format name");
@@ -271,7 +271,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
         case QCOW2_EXT_MAGIC_FEATURE_TABLE:
             if (p_feature_table != NULL) {
                 void *feature_table = g_malloc0(ext.len + 2 * sizeof(Qcow2Feature));
-                ret = bdrv_pread(bs->file, offset , feature_table, ext.len);
+                ret = bdrv_pread(bs->file, offset, ext.len, feature_table, 0);
                 if (ret < 0) {
                     error_setg_errno(errp, -ret, "ERROR: ext_feature_table: "
                                      "Could not read table");
@@ -296,7 +296,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
                 return -EINVAL;
             }
 
-            ret = bdrv_pread(bs->file, offset, &s->crypto_header, ext.len);
+            ret = bdrv_pread(bs->file, offset, ext.len, &s->crypto_header, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret,
                                  "Unable to read CRYPTO header extension");
@@ -352,7 +352,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
                 break;
             }
 
-            ret = bdrv_pread(bs->file, offset, &bitmaps_ext, ext.len);
+            ret = bdrv_pread(bs->file, offset, ext.len, &bitmaps_ext, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret, "bitmaps_ext: "
                                  "Could not read ext header");
@@ -416,7 +416,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
         case QCOW2_EXT_MAGIC_DATA_FILE:
         {
             s->image_data_file = g_malloc0(ext.len + 1);
-            ret = bdrv_pread(bs->file, offset, s->image_data_file, ext.len);
+            ret = bdrv_pread(bs->file, offset, ext.len, s->image_data_file, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret,
                                  "ERROR: Could not read data file name");
@@ -440,7 +440,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
                 uext->len = ext.len;
                 QLIST_INSERT_HEAD(&s->unknown_header_ext, uext, next);
 
-                ret = bdrv_pread(bs->file, offset , uext->data, uext->len);
+                ret = bdrv_pread(bs->file, offset, uext->len, uext->data, 0);
                 if (ret < 0) {
                     error_setg_errno(errp, -ret, "ERROR: unknown extension: "
                                      "Could not read data");
@@ -516,12 +516,9 @@ int qcow2_mark_dirty(BlockDriverState *bs)
     }
 
     val = cpu_to_be64(s->incompatible_features | QCOW2_INCOMPAT_DIRTY);
-    ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, incompatible_features),
-                      &val, sizeof(val));
-    if (ret < 0) {
-        return ret;
-    }
-    ret = bdrv_flush(bs->file->bs);
+    ret = bdrv_pwrite_sync(bs->file,
+                           offsetof(QCowHeader, incompatible_features),
+                           sizeof(val), &val, 0);
     if (ret < 0) {
         return ret;
     }
@@ -1308,7 +1305,7 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
     uint64_t l1_vm_state_index;
     bool update_header = false;
 
-    ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
+    ret = bdrv_pread(bs->file, 0, sizeof(header), &header, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not read qcow2 header");
         goto fail;
@@ -1384,8 +1381,9 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
     if (header.header_length > sizeof(header)) {
         s->unknown_header_fields_size = header.header_length - sizeof(header);
         s->unknown_header_fields = g_malloc(s->unknown_header_fields_size);
-        ret = bdrv_pread(bs->file, sizeof(header), s->unknown_header_fields,
-                         s->unknown_header_fields_size);
+        ret = bdrv_pread(bs->file, sizeof(header),
+                         s->unknown_header_fields_size,
+                         s->unknown_header_fields, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Could not read unknown qcow2 header "
                              "fields");
@@ -1580,8 +1578,8 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
             ret = -ENOMEM;
             goto fail;
         }
-        ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
-                         s->l1_size * L1E_SIZE);
+        ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_size * L1E_SIZE,
+                         s->l1_table, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Could not read L1 table");
             goto fail;
@@ -1698,8 +1696,8 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
             ret = -EINVAL;
             goto fail;
         }
-        ret = bdrv_pread(bs->file, header.backing_file_offset,
-                         bs->auto_backing_file, len);
+        ret = bdrv_pread(bs->file, header.backing_file_offset, len,
+                         bs->auto_backing_file, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Could not read backing file name");
             goto fail;
@@ -3081,7 +3079,7 @@ int qcow2_update_header(BlockDriverState *bs)
     }
 
     /* Write the new header */
-    ret = bdrv_pwrite(bs->file, 0, header, s->cluster_size);
+    ret = bdrv_pwrite(bs->file, 0, s->cluster_size, header, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -3668,7 +3666,7 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
             cpu_to_be64(QCOW2_INCOMPAT_EXTL2);
     }
 
-    ret = blk_pwrite(blk, 0, header, cluster_size, 0);
+    ret = blk_pwrite(blk, 0, cluster_size, header, 0);
     g_free(header);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not write qcow2 header");
@@ -3678,7 +3676,7 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
     /* Write a refcount table with one refcount block */
     refcount_table = g_malloc0(2 * cluster_size);
     refcount_table[0] = cpu_to_be64(2 * cluster_size);
-    ret = blk_pwrite(blk, cluster_size, refcount_table, 2 * cluster_size, 0);
+    ret = blk_pwrite(blk, cluster_size, 2 * cluster_size, refcount_table, 0);
     g_free(refcount_table);
 
     if (ret < 0) {
@@ -4550,8 +4548,8 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
 
     /* write updated header.size */
     offset = cpu_to_be64(offset);
-    ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),
-                           &offset, sizeof(offset));
+    ret = bdrv_co_pwrite_sync(bs->file, offsetof(QCowHeader, size),
+                              sizeof(offset), &offset, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to update the image size");
         goto fail;
@@ -4828,7 +4826,7 @@ static int make_completely_empty(BlockDriverState *bs)
     l1_ofs_rt_ofs_cls.reftable_offset = cpu_to_be64(s->cluster_size);
     l1_ofs_rt_ofs_cls.reftable_clusters = cpu_to_be32(1);
     ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, l1_table_offset),
-                           &l1_ofs_rt_ofs_cls, sizeof(l1_ofs_rt_ofs_cls));
+                           sizeof(l1_ofs_rt_ofs_cls), &l1_ofs_rt_ofs_cls, 0);
     if (ret < 0) {
         goto fail_broken_refcounts;
     }
@@ -4859,8 +4857,8 @@ static int make_completely_empty(BlockDriverState *bs)
 
     /* Enter the first refblock into the reftable */
     rt_entry = cpu_to_be64(2 * s->cluster_size);
-    ret = bdrv_pwrite_sync(bs->file, s->cluster_size,
-                           &rt_entry, sizeof(rt_entry));
+    ret = bdrv_pwrite_sync(bs->file, s->cluster_size, sizeof(rt_entry),
+                           &rt_entry, 0);
     if (ret < 0) {
         goto fail_broken_refcounts;
     }

block/qed.c

@@ -87,14 +87,9 @@ static void qed_header_cpu_to_le(const QEDHeader *cpu, QEDHeader *le)
 int qed_write_header_sync(BDRVQEDState *s)
 {
     QEDHeader le;
-    int ret;
 
     qed_header_cpu_to_le(&s->header, &le);
-    ret = bdrv_pwrite(s->bs->file, 0, &le, sizeof(le));
-    if (ret != sizeof(le)) {
-        return ret;
-    }
-    return 0;
+    return bdrv_pwrite(s->bs->file, 0, sizeof(le), &le, 0);
 }
 
 /**
@@ -207,7 +202,7 @@ static int qed_read_string(BdrvChild *file, uint64_t offset, size_t n,
     if (n >= buflen) {
         return -EINVAL;
     }
-    ret = bdrv_pread(file, offset, buf, n);
+    ret = bdrv_pread(file, offset, n, buf, 0);
     if (ret < 0) {
         return ret;
     }
@@ -392,7 +387,7 @@ static int coroutine_fn bdrv_qed_do_open(BlockDriverState *bs, QDict *options,
     int64_t file_size;
     int ret;
 
-    ret = bdrv_pread(bs->file, 0, &le_header, sizeof(le_header));
+    ret = bdrv_pread(bs->file, 0, sizeof(le_header), &le_header, 0);
     if (ret < 0) {
         error_setg(errp, "Failed to read QED header");
         return ret;
@@ -710,18 +705,18 @@ static int coroutine_fn bdrv_qed_co_create(BlockdevCreateOptions *opts,
     }
 
     qed_header_cpu_to_le(&header, &le_header);
-    ret = blk_pwrite(blk, 0, &le_header, sizeof(le_header), 0);
+    ret = blk_pwrite(blk, 0, sizeof(le_header), &le_header, 0);
     if (ret < 0) {
         goto out;
     }
-    ret = blk_pwrite(blk, sizeof(le_header), qed_opts->backing_file,
-                     header.backing_filename_size, 0);
+    ret = blk_pwrite(blk, sizeof(le_header), header.backing_filename_size,
+                     qed_opts->backing_file, 0);
     if (ret < 0) {
         goto out;
     }
 
     l1_table = g_malloc0(l1_size);
-    ret = blk_pwrite(blk, header.l1_table_offset, l1_table, l1_size, 0);
+    ret = blk_pwrite(blk, header.l1_table_offset, l1_size, l1_table, 0);
     if (ret < 0) {
         goto out;
     }
@@ -1545,7 +1540,7 @@ static int bdrv_qed_change_backing_file(BlockDriverState *bs,
     }
 
     /* Write new header */
-    ret = bdrv_pwrite_sync(bs->file, 0, buffer, buffer_len);
+    ret = bdrv_pwrite_sync(bs->file, 0, buffer_len, buffer, 0);
     g_free(buffer);
     if (ret == 0) {
         memcpy(&s->header, &new_header, sizeof(new_header));

block/vdi.c

@@ -385,7 +385,7 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
 
     logout("\n");
 
-    ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
+    ret = bdrv_pread(bs->file, 0, sizeof(header), &header, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -485,8 +485,8 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    ret = bdrv_pread(bs->file, header.offset_bmap, s->bmap,
-                     bmap_size * SECTOR_SIZE);
+    ret = bdrv_pread(bs->file, header.offset_bmap, bmap_size * SECTOR_SIZE,
+                     s->bmap, 0);
     if (ret < 0) {
         goto fail_free_bmap;
     }
@@ -664,7 +664,7 @@ vdi_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
              * so this full-cluster write does not overlap a partial write
              * of the same cluster, issued from the "else" branch.
              */
-            ret = bdrv_pwrite(bs->file, data_offset, block, s->block_size);
+            ret = bdrv_pwrite(bs->file, data_offset, s->block_size, block, 0);
             qemu_co_rwlock_unlock(&s->bmap_lock);
         } else {
 nonallocating_write:
@@ -709,7 +709,7 @@ nonallocating_write:
         assert(VDI_IS_ALLOCATED(bmap_first));
         *header = s->header;
         vdi_header_to_le(header);
-        ret = bdrv_pwrite(bs->file, 0, header, sizeof(*header));
+        ret = bdrv_pwrite(bs->file, 0, sizeof(*header), header, 0);
         g_free(header);
 
         if (ret < 0) {
@@ -726,11 +726,11 @@ nonallocating_write:
         base = ((uint8_t *)&s->bmap[0]) + bmap_first * SECTOR_SIZE;
         logout("will write %u block map sectors starting from entry %u\n",
                n_sectors, bmap_first);
-        ret = bdrv_pwrite(bs->file, offset * SECTOR_SIZE, base,
-                          n_sectors * SECTOR_SIZE);
+        ret = bdrv_pwrite(bs->file, offset * SECTOR_SIZE,
+                          n_sectors * SECTOR_SIZE, base, 0);
     }
 
-    return ret < 0 ? ret : 0;
+    return ret;
 }
 
 static int coroutine_fn vdi_co_do_create(BlockdevCreateOptions *create_options,
@@ -845,7 +845,7 @@ static int coroutine_fn vdi_co_do_create(BlockdevCreateOptions *create_options,
         vdi_header_print(&header);
     }
     vdi_header_to_le(&header);
-    ret = blk_pwrite(blk, offset, &header, sizeof(header), 0);
+    ret = blk_pwrite(blk, offset, sizeof(header), &header, 0);
     if (ret < 0) {
         error_setg(errp, "Error writing header");
         goto exit;
@@ -866,7 +866,7 @@ static int coroutine_fn vdi_co_do_create(BlockdevCreateOptions *create_options,
                 bmap[i] = VDI_UNALLOCATED;
             }
         }
-        ret = blk_pwrite(blk, offset, bmap, bmap_size, 0);
+        ret = blk_pwrite(blk, offset, bmap_size, bmap, 0);
         if (ret < 0) {
             error_setg(errp, "Error writing bmap");
             goto exit;

block/vhdx-log.c

@@ -84,7 +84,7 @@ static int vhdx_log_peek_hdr(BlockDriverState *bs, VHDXLogEntries *log,
 
     offset = log->offset + read;
 
-    ret = bdrv_pread(bs->file, offset, hdr, sizeof(VHDXLogEntryHeader));
+    ret = bdrv_pread(bs->file, offset, sizeof(VHDXLogEntryHeader), hdr, 0);
     if (ret < 0) {
         goto exit;
     }
@@ -144,7 +144,7 @@ static int vhdx_log_read_sectors(BlockDriverState *bs, VHDXLogEntries *log,
         }
         offset = log->offset + read;
 
-        ret = bdrv_pread(bs->file, offset, buffer, VHDX_LOG_SECTOR_SIZE);
+        ret = bdrv_pread(bs->file, offset, VHDX_LOG_SECTOR_SIZE, buffer, 0);
         if (ret < 0) {
             goto exit;
         }
@@ -194,8 +194,8 @@ static int vhdx_log_write_sectors(BlockDriverState *bs, VHDXLogEntries *log,
             /* full */
             break;
         }
-        ret = bdrv_pwrite(bs->file, offset, buffer_tmp,
-                          VHDX_LOG_SECTOR_SIZE);
+        ret = bdrv_pwrite(bs->file, offset, VHDX_LOG_SECTOR_SIZE, buffer_tmp,
+                          0);
         if (ret < 0) {
             goto exit;
         }
@@ -466,8 +466,8 @@ static int vhdx_log_flush_desc(BlockDriverState *bs, VHDXLogDescriptor *desc,
 
     /* count is only > 1 if we are writing zeroes */
     for (i = 0; i < count; i++) {
-        ret = bdrv_pwrite_sync(bs->file, file_offset, buffer,
-                               VHDX_LOG_SECTOR_SIZE);
+        ret = bdrv_pwrite_sync(bs->file, file_offset, VHDX_LOG_SECTOR_SIZE,
+                               buffer, 0);
         if (ret < 0) {
             goto exit;
         }
@@ -970,8 +970,8 @@ static int vhdx_log_write(BlockDriverState *bs, BDRVVHDXState *s,
 
         if (i == 0 && leading_length) {
             /* partial sector at the front of the buffer */
-            ret = bdrv_pread(bs->file, file_offset, merged_sector,
-                             VHDX_LOG_SECTOR_SIZE);
+            ret = bdrv_pread(bs->file, file_offset, VHDX_LOG_SECTOR_SIZE,
+                             merged_sector, 0);
             if (ret < 0) {
                 goto exit;
             }
@@ -980,10 +980,9 @@ static int vhdx_log_write(BlockDriverState *bs, BDRVVHDXState *s,
             sector_write = merged_sector;
         } else if (i == sectors - 1 && trailing_length) {
             /* partial sector at the end of the buffer */
-            ret = bdrv_pread(bs->file,
-                            file_offset,
-                            merged_sector + trailing_length,
-                            VHDX_LOG_SECTOR_SIZE - trailing_length);
+            ret = bdrv_pread(bs->file, file_offset,
+                             VHDX_LOG_SECTOR_SIZE - trailing_length,
+                             merged_sector + trailing_length, 0);
             if (ret < 0) {
                 goto exit;
             }

block/vhdx.c

@@ -326,7 +326,7 @@ static int vhdx_write_header(BdrvChild *file, VHDXHeader *hdr,
     buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE);
     if (read) {
         /* if true, we can't assume the extra reserved bytes are 0 */
-        ret = bdrv_pread(file, offset, buffer, VHDX_HEADER_SIZE);
+        ret = bdrv_pread(file, offset, VHDX_HEADER_SIZE, buffer, 0);
         if (ret < 0) {
             goto exit;
         }
@@ -340,7 +340,7 @@ static int vhdx_write_header(BdrvChild *file, VHDXHeader *hdr,
     vhdx_header_le_export(hdr, header_le);
     vhdx_update_checksum(buffer, VHDX_HEADER_SIZE,
                          offsetof(VHDXHeader, checksum));
-    ret = bdrv_pwrite_sync(file, offset, header_le, sizeof(VHDXHeader));
+    ret = bdrv_pwrite_sync(file, offset, sizeof(VHDXHeader), header_le, 0);
 
 exit:
     qemu_vfree(buffer);
@@ -440,8 +440,8 @@ static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s,
     /* We have to read the whole VHDX_HEADER_SIZE instead of
      * sizeof(VHDXHeader), because the checksum is over the whole
      * region */
-    ret = bdrv_pread(bs->file, VHDX_HEADER1_OFFSET, buffer,
-                     VHDX_HEADER_SIZE);
+    ret = bdrv_pread(bs->file, VHDX_HEADER1_OFFSET, VHDX_HEADER_SIZE, buffer,
+                     0);
     if (ret < 0) {
         goto fail;
     }
@@ -457,8 +457,8 @@ static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s,
         }
     }
 
-    ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, buffer,
-                     VHDX_HEADER_SIZE);
+    ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, VHDX_HEADER_SIZE, buffer,
+                     0);
     if (ret < 0) {
         goto fail;
     }
@@ -531,8 +531,8 @@ static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s)
      * whole block */
     buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE);
 
-    ret = bdrv_pread(bs->file, VHDX_REGION_TABLE_OFFSET, buffer,
-                     VHDX_HEADER_BLOCK_SIZE);
+    ret = bdrv_pread(bs->file, VHDX_REGION_TABLE_OFFSET,
+                     VHDX_HEADER_BLOCK_SIZE, buffer, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -644,8 +644,8 @@ static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s)
 
     buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE);
 
-    ret = bdrv_pread(bs->file, s->metadata_rt.file_offset, buffer,
-                     VHDX_METADATA_TABLE_MAX_SIZE);
+    ret = bdrv_pread(bs->file, s->metadata_rt.file_offset,
+                     VHDX_METADATA_TABLE_MAX_SIZE, buffer, 0);
     if (ret < 0) {
         goto exit;
     }
@@ -750,8 +750,9 @@ static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s)
     ret = bdrv_pread(bs->file,
                      s->metadata_entries.file_parameters_entry.offset
                                          + s->metadata_rt.file_offset,
+                     sizeof(s->params),
                      &s->params,
-                     sizeof(s->params));
+                     0);
 
     if (ret < 0) {
         goto exit;
@@ -785,24 +786,27 @@ static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s)
     ret = bdrv_pread(bs->file,
                      s->metadata_entries.virtual_disk_size_entry.offset
                                            + s->metadata_rt.file_offset,
+                     sizeof(uint64_t),
                      &s->virtual_disk_size,
-                     sizeof(uint64_t));
+                     0);
     if (ret < 0) {
         goto exit;
     }
     ret = bdrv_pread(bs->file,
                      s->metadata_entries.logical_sector_size_entry.offset
                                              + s->metadata_rt.file_offset,
+                     sizeof(uint32_t),
                      &s->logical_sector_size,
-                     sizeof(uint32_t));
+                     0);
     if (ret < 0) {
         goto exit;
     }
     ret = bdrv_pread(bs->file,
                      s->metadata_entries.phys_sector_size_entry.offset
                                           + s->metadata_rt.file_offset,
+                     sizeof(uint32_t),
                      &s->physical_sector_size,
-                     sizeof(uint32_t));
+                     0);
     if (ret < 0) {
         goto exit;
     }
@@ -1010,7 +1014,7 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
     QLIST_INIT(&s->regions);
 
     /* validate the file signature */
-    ret = bdrv_pread(bs->file, 0, &signature, sizeof(uint64_t));
+    ret = bdrv_pread(bs->file, 0, sizeof(uint64_t), &signature, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -1069,7 +1073,7 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    ret = bdrv_pread(bs->file, s->bat_offset, s->bat, s->bat_rt.length);
+    ret = bdrv_pread(bs->file, s->bat_offset, s->bat_rt.length, s->bat, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -1661,13 +1665,13 @@ static int vhdx_create_new_metadata(BlockBackend *blk,
                                    VHDX_META_FLAGS_IS_VIRTUAL_DISK;
     vhdx_metadata_entry_le_export(&md_table_entry[4]);
 
-    ret = blk_pwrite(blk, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE, 0);
+    ret = blk_pwrite(blk, metadata_offset, VHDX_HEADER_BLOCK_SIZE, buffer, 0);
     if (ret < 0) {
         goto exit;
     }
 
-    ret = blk_pwrite(blk, metadata_offset + (64 * KiB), entry_buffer,
-                     VHDX_METADATA_ENTRY_BUFFER_SIZE, 0);
+    ret = blk_pwrite(blk, metadata_offset + (64 * KiB),
+                     VHDX_METADATA_ENTRY_BUFFER_SIZE, entry_buffer, 0);
     if (ret < 0) {
         goto exit;
     }
@@ -1752,7 +1756,7 @@ static int vhdx_create_bat(BlockBackend *blk, BDRVVHDXState *s,
             s->bat[sinfo.bat_idx] = cpu_to_le64(s->bat[sinfo.bat_idx]);
             sector_num += s->sectors_per_block;
         }
-        ret = blk_pwrite(blk, file_offset, s->bat, length, 0);
+        ret = blk_pwrite(blk, file_offset, length, s->bat, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to write the BAT");
             goto exit;
@@ -1856,15 +1860,15 @@ static int vhdx_create_new_region_table(BlockBackend *blk,
     }
 
     /* Now write out the region headers to disk */
-    ret = blk_pwrite(blk, VHDX_REGION_TABLE_OFFSET, buffer,
-                     VHDX_HEADER_BLOCK_SIZE, 0);
+    ret = blk_pwrite(blk, VHDX_REGION_TABLE_OFFSET, VHDX_HEADER_BLOCK_SIZE,
+                     buffer, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to write first region table");
         goto exit;
     }
 
-    ret = blk_pwrite(blk, VHDX_REGION_TABLE2_OFFSET, buffer,
-                     VHDX_HEADER_BLOCK_SIZE, 0);
+    ret = blk_pwrite(blk, VHDX_REGION_TABLE2_OFFSET, VHDX_HEADER_BLOCK_SIZE,
+                     buffer, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to write second region table");
         goto exit;
@@ -2008,7 +2012,7 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
     creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL,
                               &creator_items, NULL);
     signature = cpu_to_le64(VHDX_FILE_SIGNATURE);
-    ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature),
+    ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET, sizeof(signature), &signature,
                      0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Failed to write file signature");
@@ -2016,7 +2020,7 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
     }
     if (creator) {
         ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET + sizeof(signature),
-                         creator, creator_items * sizeof(gunichar2), 0);
+                         creator_items * sizeof(gunichar2), creator, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to write creator field");
             goto delete_and_exit;

block/vmdk.c

@@ -307,7 +307,7 @@ static int vmdk_read_cid(BlockDriverState *bs, int parent, uint32_t *pcid)
     int ret;
 
     desc = g_malloc0(DESC_SIZE);
-    ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
+    ret = bdrv_pread(bs->file, s->desc_offset, DESC_SIZE, desc, 0);
     if (ret < 0) {
         goto out;
     }
@@ -348,7 +348,7 @@ static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
 
     desc = g_malloc0(DESC_SIZE);
     tmp_desc = g_malloc0(DESC_SIZE);
-    ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
+    ret = bdrv_pread(bs->file, s->desc_offset, DESC_SIZE, desc, 0);
     if (ret < 0) {
         goto out;
     }
@@ -368,7 +368,7 @@ static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
         pstrcat(desc, DESC_SIZE, tmp_desc);
     }
 
-    ret = bdrv_pwrite_sync(bs->file, s->desc_offset, desc, DESC_SIZE);
+    ret = bdrv_pwrite_sync(bs->file, s->desc_offset, DESC_SIZE, desc, 0);
 
 out:
     g_free(desc);
@@ -469,11 +469,10 @@ static int vmdk_parent_open(BlockDriverState *bs)
     int ret;
 
     desc = g_malloc0(DESC_SIZE + 1);
-    ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
+    ret = bdrv_pread(bs->file, s->desc_offset, DESC_SIZE, desc, 0);
     if (ret < 0) {
         goto out;
     }
-    ret = 0;
 
     p_name = strstr(desc, "parentFileNameHint");
     if (p_name != NULL) {
@@ -589,10 +588,8 @@ static int vmdk_init_tables(BlockDriverState *bs, VmdkExtent *extent,
         return -ENOMEM;
     }
 
-    ret = bdrv_pread(extent->file,
-                     extent->l1_table_offset,
-                     extent->l1_table,
-                     l1_size);
+    ret = bdrv_pread(extent->file, extent->l1_table_offset, l1_size,
+                     extent->l1_table, 0);
     if (ret < 0) {
         bdrv_refresh_filename(extent->file->bs);
         error_setg_errno(errp, -ret,
@@ -616,10 +613,8 @@ static int vmdk_init_tables(BlockDriverState *bs, VmdkExtent *extent,
             ret = -ENOMEM;
             goto fail_l1;
         }
-        ret = bdrv_pread(extent->file,
-                         extent->l1_backup_table_offset,
-                         extent->l1_backup_table,
-                         l1_size);
+        ret = bdrv_pread(extent->file, extent->l1_backup_table_offset,
+                         l1_size, extent->l1_backup_table, 0);
         if (ret < 0) {
             bdrv_refresh_filename(extent->file->bs);
             error_setg_errno(errp, -ret,
@@ -651,7 +646,7 @@ static int vmdk_open_vmfs_sparse(BlockDriverState *bs,
     VMDK3Header header;
     VmdkExtent *extent = NULL;
 
-    ret = bdrv_pread(file, sizeof(magic), &header, sizeof(header));
+    ret = bdrv_pread(file, sizeof(magic), sizeof(header), &header, 0);
     if (ret < 0) {
         bdrv_refresh_filename(file->bs);
         error_setg_errno(errp, -ret,
@@ -815,7 +810,7 @@ static int vmdk_open_se_sparse(BlockDriverState *bs,
 
     assert(sizeof(const_header) == SECTOR_SIZE);
 
-    ret = bdrv_pread(file, 0, &const_header, sizeof(const_header));
+    ret = bdrv_pread(file, 0, sizeof(const_header), &const_header, 0);
     if (ret < 0) {
         bdrv_refresh_filename(file->bs);
         error_setg_errno(errp, -ret,
@@ -832,9 +827,8 @@ static int vmdk_open_se_sparse(BlockDriverState *bs,
 
     assert(sizeof(volatile_header) == SECTOR_SIZE);
 
-    ret = bdrv_pread(file,
-                     const_header.volatile_header_offset * SECTOR_SIZE,
-                     &volatile_header, sizeof(volatile_header));
+    ret = bdrv_pread(file, const_header.volatile_header_offset * SECTOR_SIZE,
+                     sizeof(volatile_header), &volatile_header, 0);
     if (ret < 0) {
         bdrv_refresh_filename(file->bs);
         error_setg_errno(errp, -ret,
@@ -904,13 +898,13 @@ static char *vmdk_read_desc(BdrvChild *file, uint64_t desc_offset, Error **errp)
     size = MIN(size, (1 << 20) - 1);  /* avoid unbounded allocation */
     buf = g_malloc(size + 1);
 
-    ret = bdrv_pread(file, desc_offset, buf, size);
+    ret = bdrv_pread(file, desc_offset, size, buf, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not read from file");
         g_free(buf);
         return NULL;
     }
-    buf[ret] = 0;
+    buf[size] = 0;
 
     return buf;
 }
@@ -928,7 +922,7 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
     int64_t l1_backup_offset = 0;
     bool compressed;
 
-    ret = bdrv_pread(file, sizeof(magic), &header, sizeof(header));
+    ret = bdrv_pread(file, sizeof(magic), sizeof(header), &header, 0);
     if (ret < 0) {
         bdrv_refresh_filename(file->bs);
         error_setg_errno(errp, -ret,
@@ -979,9 +973,8 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
             } QEMU_PACKED eos_marker;
         } QEMU_PACKED footer;
 
-        ret = bdrv_pread(file,
-            bs->file->bs->total_sectors * 512 - 1536,
-            &footer, sizeof(footer));
+        ret = bdrv_pread(file, bs->file->bs->total_sectors * 512 - 1536,
+                         sizeof(footer), &footer, 0);
         if (ret < 0) {
             error_setg_errno(errp, -ret, "Failed to read footer");
             return ret;
@@ -1448,16 +1441,16 @@ static int get_whole_cluster(BlockDriverState *bs,
         if (copy_from_backing) {
             /* qcow2 emits this on bs->file instead of bs->backing */
             BLKDBG_EVENT(extent->file, BLKDBG_COW_READ);
-            ret = bdrv_pread(bs->backing, offset, whole_grain,
-                             skip_start_bytes);
+            ret = bdrv_pread(bs->backing, offset, skip_start_bytes,
+                             whole_grain, 0);
             if (ret < 0) {
                 ret = VMDK_ERROR;
                 goto exit;
             }
         }
         BLKDBG_EVENT(extent->file, BLKDBG_COW_WRITE);
-        ret = bdrv_pwrite(extent->file, cluster_offset, whole_grain,
-                          skip_start_bytes);
+        ret = bdrv_pwrite(extent->file, cluster_offset, skip_start_bytes,
+                          whole_grain, 0);
         if (ret < 0) {
             ret = VMDK_ERROR;
             goto exit;
@@ -1469,8 +1462,8 @@ static int get_whole_cluster(BlockDriverState *bs,
             /* qcow2 emits this on bs->file instead of bs->backing */
             BLKDBG_EVENT(extent->file, BLKDBG_COW_READ);
             ret = bdrv_pread(bs->backing, offset + skip_end_bytes,
-                             whole_grain + skip_end_bytes,
-                             cluster_bytes - skip_end_bytes);
+                             cluster_bytes - skip_end_bytes,
+                             whole_grain + skip_end_bytes, 0);
             if (ret < 0) {
                 ret = VMDK_ERROR;
                 goto exit;
@@ -1478,8 +1471,8 @@ static int get_whole_cluster(BlockDriverState *bs,
         }
         BLKDBG_EVENT(extent->file, BLKDBG_COW_WRITE);
         ret = bdrv_pwrite(extent->file, cluster_offset + skip_end_bytes,
-                          whole_grain + skip_end_bytes,
-                          cluster_bytes - skip_end_bytes);
+                          cluster_bytes - skip_end_bytes,
+                          whole_grain + skip_end_bytes, 0);
         if (ret < 0) {
             ret = VMDK_ERROR;
             goto exit;
@@ -1501,7 +1494,7 @@ static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data,
     if (bdrv_pwrite(extent->file,
                 ((int64_t)m_data->l2_offset * 512)
                     + (m_data->l2_index * sizeof(offset)),
-                &offset, sizeof(offset)) < 0) {
+                sizeof(offset), &offset, 0) < 0) {
         return VMDK_ERROR;
     }
     /* update backup L2 table */
@@ -1510,7 +1503,7 @@ static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data,
         if (bdrv_pwrite(extent->file,
                     ((int64_t)m_data->l2_offset * 512)
                         + (m_data->l2_index * sizeof(offset)),
-                    &offset, sizeof(offset)) < 0) {
+                    sizeof(offset), &offset, 0) < 0) {
             return VMDK_ERROR;
         }
     }
@@ -1633,9 +1626,10 @@ static int get_cluster_offset(BlockDriverState *bs,
     BLKDBG_EVENT(extent->file, BLKDBG_L2_LOAD);
     if (bdrv_pread(extent->file,
                 (int64_t)l2_offset * 512,
+                l2_size_bytes,
                 l2_table,
-                l2_size_bytes
-            ) != l2_size_bytes) {
+                0
+            ) < 0) {
         return VMDK_ERROR;
     }
 
@@ -1903,9 +1897,7 @@ static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset,
     cluster_buf = g_malloc(buf_bytes);
     uncomp_buf = g_malloc(cluster_bytes);
     BLKDBG_EVENT(extent->file, BLKDBG_READ_COMPRESSED);
-    ret = bdrv_pread(extent->file,
-                cluster_offset,
-                cluster_buf, buf_bytes);
+    ret = bdrv_pread(extent->file, cluster_offset, buf_bytes, cluster_buf, 0);
     if (ret < 0) {
         goto out;
     }
@@ -2244,12 +2236,12 @@ static int vmdk_init_extent(BlockBackend *blk,
     header.check_bytes[3] = 0xa;
 
     /* write all the data */
-    ret = blk_pwrite(blk, 0, &magic, sizeof(magic), 0);
+    ret = blk_pwrite(blk, 0, sizeof(magic), &magic, 0);
     if (ret < 0) {
         error_setg(errp, QERR_IO_ERROR);
         goto exit;
     }
-    ret = blk_pwrite(blk, sizeof(magic), &header, sizeof(header), 0);
+    ret = blk_pwrite(blk, sizeof(magic), sizeof(header), &header, 0);
     if (ret < 0) {
         error_setg(errp, QERR_IO_ERROR);
         goto exit;
@@ -2269,7 +2261,7 @@ static int vmdk_init_extent(BlockBackend *blk,
         gd_buf[i] = cpu_to_le32(tmp);
     }
     ret = blk_pwrite(blk, le64_to_cpu(header.rgd_offset) * BDRV_SECTOR_SIZE,
-                     gd_buf, gd_buf_size, 0);
+                     gd_buf_size, gd_buf, 0);
     if (ret < 0) {
         error_setg(errp, QERR_IO_ERROR);
         goto exit;
@@ -2281,7 +2273,7 @@ static int vmdk_init_extent(BlockBackend *blk,
         gd_buf[i] = cpu_to_le32(tmp);
     }
     ret = blk_pwrite(blk, le64_to_cpu(header.gd_offset) * BDRV_SECTOR_SIZE,
-                     gd_buf, gd_buf_size, 0);
+                     gd_buf_size, gd_buf, 0);
     if (ret < 0) {
         error_setg(errp, QERR_IO_ERROR);
     }
@@ -2592,7 +2584,7 @@ static int coroutine_fn vmdk_co_do_create(int64_t size,
         desc_offset = 0x200;
     }
 
-    ret = blk_pwrite(blk, desc_offset, desc, desc_len, 0);
+    ret = blk_pwrite(blk, desc_offset, desc_len, desc, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Could not write description");
         goto exit;

block/vpc.c

@@ -252,7 +252,7 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    ret = bdrv_pread(bs->file, 0, &s->footer, sizeof(s->footer));
+    ret = bdrv_pread(bs->file, 0, sizeof(s->footer), &s->footer, 0);
     if (ret < 0) {
         error_setg(errp, "Unable to read VHD header");
         goto fail;
@@ -272,8 +272,8 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
         }
 
         /* If a fixed disk, the footer is found only at the end of the file */
-        ret = bdrv_pread(bs->file, offset - sizeof(*footer),
-                         footer, sizeof(*footer));
+        ret = bdrv_pread(bs->file, offset - sizeof(*footer), sizeof(*footer),
+                         footer, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -347,7 +347,7 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
 
     if (disk_type == VHD_DYNAMIC) {
         ret = bdrv_pread(bs->file, be64_to_cpu(footer->data_offset),
-                         &dyndisk_header, sizeof(dyndisk_header));
+                         sizeof(dyndisk_header), &dyndisk_header, 0);
         if (ret < 0) {
             error_setg(errp, "Error reading dynamic VHD header");
             goto fail;
@@ -401,8 +401,8 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
 
         s->bat_offset = be64_to_cpu(dyndisk_header.table_offset);
 
-        ret = bdrv_pread(bs->file, s->bat_offset, s->pagetable,
-                         pagetable_size);
+        ret = bdrv_pread(bs->file, s->bat_offset, pagetable_size,
+                         s->pagetable, 0);
         if (ret < 0) {
             error_setg(errp, "Error reading pagetable");
             goto fail;
@@ -516,7 +516,8 @@ static inline int64_t get_image_offset(BlockDriverState *bs, uint64_t offset,
 
         s->last_bitmap_offset = bitmap_offset;
         memset(bitmap, 0xff, s->bitmap_size);
-        r = bdrv_pwrite_sync(bs->file, bitmap_offset, bitmap, s->bitmap_size);
+        r = bdrv_pwrite_sync(bs->file, bitmap_offset, s->bitmap_size, bitmap,
+                             0);
         if (r < 0) {
             *err = r;
             return -2;
@@ -538,7 +539,7 @@ static int rewrite_footer(BlockDriverState *bs)
     BDRVVPCState *s = bs->opaque;
     int64_t offset = s->free_data_block_offset;
 
-    ret = bdrv_pwrite_sync(bs->file, offset, &s->footer, sizeof(s->footer));
+    ret = bdrv_pwrite_sync(bs->file, offset, sizeof(s->footer), &s->footer, 0);
     if (ret < 0)
         return ret;
 
@@ -572,8 +573,8 @@ static int64_t alloc_block(BlockDriverState *bs, int64_t offset)
 
     /* Initialize the block's bitmap */
     memset(bitmap, 0xff, s->bitmap_size);
-    ret = bdrv_pwrite_sync(bs->file, s->free_data_block_offset, bitmap,
-        s->bitmap_size);
+    ret = bdrv_pwrite_sync(bs->file, s->free_data_block_offset,
+                           s->bitmap_size, bitmap, 0);
     if (ret < 0) {
         return ret;
     }
@@ -587,7 +588,7 @@ static int64_t alloc_block(BlockDriverState *bs, int64_t offset)
     /* Write BAT entry to disk */
     bat_offset = s->bat_offset + (4 * index);
     bat_value = cpu_to_be32(s->pagetable[index]);
-    ret = bdrv_pwrite_sync(bs->file, bat_offset, &bat_value, 4);
+    ret = bdrv_pwrite_sync(bs->file, bat_offset, 4, &bat_value, 0);
     if (ret < 0)
         goto fail;
 
@@ -833,13 +834,13 @@ static int create_dynamic_disk(BlockBackend *blk, VHDFooter *footer,
     block_size = 0x200000;
     num_bat_entries = DIV_ROUND_UP(total_sectors, block_size / 512);
 
-    ret = blk_pwrite(blk, offset, footer, sizeof(*footer), 0);
+    ret = blk_pwrite(blk, offset, sizeof(*footer), footer, 0);
     if (ret < 0) {
         goto fail;
     }
 
     offset = 1536 + ((num_bat_entries * 4 + 511) & ~511);
-    ret = blk_pwrite(blk, offset, footer, sizeof(*footer), 0);
+    ret = blk_pwrite(blk, offset, sizeof(*footer), footer, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -849,7 +850,7 @@ static int create_dynamic_disk(BlockBackend *blk, VHDFooter *footer,
 
     memset(bat_sector, 0xFF, 512);
     for (i = 0; i < DIV_ROUND_UP(num_bat_entries * 4, 512); i++) {
-        ret = blk_pwrite(blk, offset, bat_sector, 512, 0);
+        ret = blk_pwrite(blk, offset, 512, bat_sector, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -877,7 +878,7 @@ static int create_dynamic_disk(BlockBackend *blk, VHDFooter *footer,
     /* Write the header */
     offset = 512;
 
-    ret = blk_pwrite(blk, offset, &dyndisk_header, sizeof(dyndisk_header), 0);
+    ret = blk_pwrite(blk, offset, sizeof(dyndisk_header), &dyndisk_header, 0);
     if (ret < 0) {
         goto fail;
     }
@@ -900,8 +901,8 @@ static int create_fixed_disk(BlockBackend *blk, VHDFooter *footer,
         return ret;
     }
 
-    ret = blk_pwrite(blk, total_size - sizeof(*footer),
-                     footer, sizeof(*footer), 0);
+    ret = blk_pwrite(blk, total_size - sizeof(*footer), sizeof(*footer),
+                     footer, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "Unable to write VHD header");
         return ret;

block/vvfat.c

@@ -1488,8 +1488,8 @@ static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
                 DLOG(fprintf(stderr, "sectors %" PRId64 "+%" PRId64
                              " allocated\n", sector_num,
                              n >> BDRV_SECTOR_BITS));
-                if (bdrv_pread(s->qcow, sector_num * BDRV_SECTOR_SIZE,
-                               buf + i * 0x200, n) < 0) {
+                if (bdrv_pread(s->qcow, sector_num * BDRV_SECTOR_SIZE, n,
+                               buf + i * 0x200, 0) < 0) {
                     return -1;
                 }
                 i += (n >> BDRV_SECTOR_BITS) - 1;
@@ -1978,7 +1978,8 @@ static uint32_t get_cluster_count_for_direntry(BDRVVVFATState* s,
                             return -1;
                         }
                         res = bdrv_pwrite(s->qcow, offset * BDRV_SECTOR_SIZE,
-                                          s->cluster_buffer, BDRV_SECTOR_SIZE);
+                                          BDRV_SECTOR_SIZE, s->cluster_buffer,
+                                          0);
                         if (res < 0) {
                             return -2;
                         }
@@ -3062,8 +3063,8 @@ DLOG(checkpoint());
      * Use qcow backend. Commit later.
      */
 DLOG(fprintf(stderr, "Write to qcow backend: %d + %d\n", (int)sector_num, nb_sectors));
-    ret = bdrv_pwrite(s->qcow, sector_num * BDRV_SECTOR_SIZE, buf,
-                      nb_sectors * BDRV_SECTOR_SIZE);
+    ret = bdrv_pwrite(s->qcow, sector_num * BDRV_SECTOR_SIZE,
+                      nb_sectors * BDRV_SECTOR_SIZE, buf, 0);
     if (ret < 0) {
         fprintf(stderr, "Error writing to qcow backend\n");
         return ret;

crypto/block-luks.c

@@ -495,7 +495,7 @@ qcrypto_block_luks_load_header(QCryptoBlock *block,
                                 void *opaque,
                                 Error **errp)
 {
-    ssize_t rv;
+    int rv;
     size_t i;
     QCryptoBlockLUKS *luks = block->opaque;
 
@@ -856,7 +856,7 @@ qcrypto_block_luks_store_key(QCryptoBlock *block,
                   QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
                   splitkey, splitkeylen,
                   opaque,
-                  errp) != splitkeylen) {
+                  errp) < 0) {
         goto cleanup;
     }
 
@@ -903,7 +903,7 @@ qcrypto_block_luks_load_key(QCryptoBlock *block,
     g_autofree uint8_t *splitkey = NULL;
     size_t splitkeylen;
     g_autofree uint8_t *possiblekey = NULL;
-    ssize_t rv;
+    int rv;
     g_autoptr(QCryptoCipher) cipher = NULL;
     uint8_t keydigest[QCRYPTO_BLOCK_LUKS_DIGEST_LEN];
     g_autoptr(QCryptoIVGen) ivgen = NULL;
@@ -1193,7 +1193,7 @@ qcrypto_block_luks_erase_key(QCryptoBlock *block,
                       garbagesplitkey,
                       splitkeylen,
                       opaque,
-                      &local_err) != splitkeylen) {
+                      &local_err) < 0) {
             error_propagate(errp, local_err);
             return -1;
         }

crypto/block.c

@@ -115,7 +115,7 @@ QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options,
 }
 
 
-static ssize_t qcrypto_block_headerlen_hdr_init_func(QCryptoBlock *block,
+static int qcrypto_block_headerlen_hdr_init_func(QCryptoBlock *block,
         size_t headerlen, void *opaque, Error **errp)
 {
     size_t *headerlenp = opaque;
@@ -126,12 +126,12 @@ static ssize_t qcrypto_block_headerlen_hdr_init_func(QCryptoBlock *block,
 }
 
 
-static ssize_t qcrypto_block_headerlen_hdr_write_func(QCryptoBlock *block,
+static int qcrypto_block_headerlen_hdr_write_func(QCryptoBlock *block,
         size_t offset, const uint8_t *buf, size_t buflen,
         void *opaque, Error **errp)
 {
     /* Discard the bytes, we're not actually writing to an image */
-    return buflen;
+    return 0;
 }
 
 

hw/arm/allwinner-h3.c

@@ -174,7 +174,7 @@ void allwinner_h3_bootrom_setup(AwH3State *s, BlockBackend *blk)
     const int64_t rom_size = 32 * KiB;
     g_autofree uint8_t *buffer = g_new0(uint8_t, rom_size);
 
-    if (blk_pread(blk, 8 * KiB, buffer, rom_size) < 0) {
+    if (blk_pread(blk, 8 * KiB, rom_size, buffer, 0) < 0) {
         error_setg(&error_fatal, "%s: failed to read BlockBackend data",
                    __func__);
         return;

hw/arm/aspeed.c

@@ -253,7 +253,7 @@ static void write_boot_rom(DriveInfo *dinfo, hwaddr addr, size_t rom_size,
     }
 
     storage = g_malloc0(rom_size);
-    if (blk_pread(blk, 0, storage, rom_size) < 0) {
+    if (blk_pread(blk, 0, rom_size, storage, 0) < 0) {
         error_setg(errp, "failed to read the initial flash content");
         return;
     }

hw/block/block.c

@@ -53,7 +53,7 @@ bool blk_check_size_and_read_all(BlockBackend *blk, void *buf, hwaddr size,
      * block device and read only on demand.
      */
     assert(size <= BDRV_REQUEST_MAX_BYTES);
-    ret = blk_pread(blk, 0, buf, size);
+    ret = blk_pread(blk, 0, size, buf, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "can't read block backend");
         return false;

hw/block/fdc.c

@@ -1628,8 +1628,8 @@ int fdctrl_transfer_handler(void *opaque, int nchan, int dma_pos, int dma_len)
         if (fdctrl->data_dir != FD_DIR_WRITE ||
             len < FD_SECTOR_LEN || rel_pos != 0) {
             /* READ & SCAN commands and realign to a sector for WRITE */
-            if (blk_pread(cur_drv->blk, fd_offset(cur_drv),
-                          fdctrl->fifo, BDRV_SECTOR_SIZE) < 0) {
+            if (blk_pread(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
+                          fdctrl->fifo, 0) < 0) {
                 FLOPPY_DPRINTF("Floppy: error getting sector %d\n",
                                fd_sector(cur_drv));
                 /* Sure, image size is too small... */
@@ -1656,8 +1656,8 @@ int fdctrl_transfer_handler(void *opaque, int nchan, int dma_pos, int dma_len)
 
             k->read_memory(fdctrl->dma, nchan, fdctrl->fifo + rel_pos,
                            fdctrl->data_pos, len);
-            if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv),
-                           fdctrl->fifo, BDRV_SECTOR_SIZE, 0) < 0) {
+            if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
+                           fdctrl->fifo, 0) < 0) {
                 FLOPPY_DPRINTF("error writing sector %d\n",
                                fd_sector(cur_drv));
                 fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
@@ -1740,8 +1740,8 @@ static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
                                    fd_sector(cur_drv));
                     return 0;
                 }
-            if (blk_pread(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo,
-                          BDRV_SECTOR_SIZE)
+            if (blk_pread(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
+                          fdctrl->fifo, 0)
                 < 0) {
                 FLOPPY_DPRINTF("error getting sector %d\n",
                                fd_sector(cur_drv));
@@ -1820,8 +1820,8 @@ static void fdctrl_format_sector(FDCtrl *fdctrl)
     }
     memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
     if (cur_drv->blk == NULL ||
-        blk_pwrite(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo,
-                   BDRV_SECTOR_SIZE, 0) < 0) {
+        blk_pwrite(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
+                   fdctrl->fifo, 0) < 0) {
         FLOPPY_DPRINTF("error formatting sector %d\n", fd_sector(cur_drv));
         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
     } else {
@@ -2244,8 +2244,8 @@ static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value)
         if (pos == FD_SECTOR_LEN - 1 ||
             fdctrl->data_pos == fdctrl->data_len) {
             cur_drv = get_cur_drv(fdctrl);
-            if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo,
-                           BDRV_SECTOR_SIZE, 0) < 0) {
+            if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
+                           fdctrl->fifo, 0) < 0) {
                 FLOPPY_DPRINTF("error writing sector %d\n",
                                fd_sector(cur_drv));
                 break;

hw/block/hd-geometry.c

@@ -63,7 +63,7 @@ static int guess_disk_lchs(BlockBackend *blk,
 
     blk_get_geometry(blk, &nb_sectors);
 
-    if (blk_pread(blk, 0, buf, BDRV_SECTOR_SIZE) < 0) {
+    if (blk_pread(blk, 0, BDRV_SECTOR_SIZE, buf, 0) < 0) {
         return -1;
     }
     /* test msdos magic */

hw/block/m25p80.c

@@ -1532,7 +1532,7 @@ static void m25p80_realize(SSIPeripheral *ss, Error **errp)
         trace_m25p80_binding(s);
         s->storage = blk_blockalign(s->blk, s->size);
 
-        if (blk_pread(s->blk, 0, s->storage, s->size) != s->size) {
+        if (blk_pread(s->blk, 0, s->size, s->storage, 0) < 0) {
             error_setg(errp, "failed to read the initial flash content");
             return;
         }

hw/block/nand.c

@@ -666,8 +666,8 @@ static void glue(nand_blk_write_, NAND_PAGE_SIZE)(NANDFlashState *s)
         sector = SECTOR(s->addr);
         off = (s->addr & PAGE_MASK) + s->offset;
         soff = SECTOR_OFFSET(s->addr);
-        if (blk_pread(s->blk, sector << BDRV_SECTOR_BITS, iobuf,
-                      PAGE_SECTORS << BDRV_SECTOR_BITS) < 0) {
+        if (blk_pread(s->blk, sector << BDRV_SECTOR_BITS,
+                      PAGE_SECTORS << BDRV_SECTOR_BITS, iobuf, 0) < 0) {
             printf("%s: read error in sector %" PRIu64 "\n", __func__, sector);
             return;
         }
@@ -679,24 +679,24 @@ static void glue(nand_blk_write_, NAND_PAGE_SIZE)(NANDFlashState *s)
                             MIN(OOB_SIZE, off + s->iolen - NAND_PAGE_SIZE));
         }
 
-        if (blk_pwrite(s->blk, sector << BDRV_SECTOR_BITS, iobuf,
-                       PAGE_SECTORS << BDRV_SECTOR_BITS, 0) < 0) {
+        if (blk_pwrite(s->blk, sector << BDRV_SECTOR_BITS,
+                       PAGE_SECTORS << BDRV_SECTOR_BITS, iobuf, 0) < 0) {
             printf("%s: write error in sector %" PRIu64 "\n", __func__, sector);
         }
     } else {
         off = PAGE_START(s->addr) + (s->addr & PAGE_MASK) + s->offset;
         sector = off >> 9;
         soff = off & 0x1ff;
-        if (blk_pread(s->blk, sector << BDRV_SECTOR_BITS, iobuf,
-                      (PAGE_SECTORS + 2) << BDRV_SECTOR_BITS) < 0) {
+        if (blk_pread(s->blk, sector << BDRV_SECTOR_BITS,
+                      (PAGE_SECTORS + 2) << BDRV_SECTOR_BITS, iobuf, 0) < 0) {
             printf("%s: read error in sector %" PRIu64 "\n", __func__, sector);
             return;
         }
 
         mem_and(iobuf + soff, s->io, s->iolen);
 
-        if (blk_pwrite(s->blk, sector << BDRV_SECTOR_BITS, iobuf,
-                       (PAGE_SECTORS + 2) << BDRV_SECTOR_BITS, 0) < 0) {
+        if (blk_pwrite(s->blk, sector << BDRV_SECTOR_BITS,
+                       (PAGE_SECTORS + 2) << BDRV_SECTOR_BITS, iobuf, 0) < 0) {
             printf("%s: write error in sector %" PRIu64 "\n", __func__, sector);
         }
     }
@@ -723,20 +723,20 @@ static void glue(nand_blk_erase_, NAND_PAGE_SIZE)(NANDFlashState *s)
         i = SECTOR(addr);
         page = SECTOR(addr + (1 << (ADDR_SHIFT + s->erase_shift)));
         for (; i < page; i ++)
-            if (blk_pwrite(s->blk, i << BDRV_SECTOR_BITS, iobuf,
-                           BDRV_SECTOR_SIZE, 0) < 0) {
+            if (blk_pwrite(s->blk, i << BDRV_SECTOR_BITS,
+                           BDRV_SECTOR_SIZE, iobuf, 0) < 0) {
                 printf("%s: write error in sector %" PRIu64 "\n", __func__, i);
             }
     } else {
         addr = PAGE_START(addr);
         page = addr >> 9;
-        if (blk_pread(s->blk, page << BDRV_SECTOR_BITS, iobuf,
-                      BDRV_SECTOR_SIZE) < 0) {
+        if (blk_pread(s->blk, page << BDRV_SECTOR_BITS,
+                      BDRV_SECTOR_SIZE, iobuf, 0) < 0) {
             printf("%s: read error in sector %" PRIu64 "\n", __func__, page);
         }
         memset(iobuf + (addr & 0x1ff), 0xff, (~addr & 0x1ff) + 1);
-        if (blk_pwrite(s->blk, page << BDRV_SECTOR_BITS, iobuf,
-                       BDRV_SECTOR_SIZE, 0) < 0) {
+        if (blk_pwrite(s->blk, page << BDRV_SECTOR_BITS,
+                       BDRV_SECTOR_SIZE, iobuf, 0) < 0) {
             printf("%s: write error in sector %" PRIu64 "\n", __func__, page);
         }
 
@@ -744,20 +744,20 @@ static void glue(nand_blk_erase_, NAND_PAGE_SIZE)(NANDFlashState *s)
         i = (addr & ~0x1ff) + 0x200;
         for (addr += ((NAND_PAGE_SIZE + OOB_SIZE) << s->erase_shift) - 0x200;
                         i < addr; i += 0x200) {
-            if (blk_pwrite(s->blk, i, iobuf, BDRV_SECTOR_SIZE, 0) < 0) {
+            if (blk_pwrite(s->blk, i, BDRV_SECTOR_SIZE, iobuf, 0) < 0) {
                 printf("%s: write error in sector %" PRIu64 "\n",
                        __func__, i >> 9);
             }
         }
 
         page = i >> 9;
-        if (blk_pread(s->blk, page << BDRV_SECTOR_BITS, iobuf,
-                      BDRV_SECTOR_SIZE) < 0) {
+        if (blk_pread(s->blk, page << BDRV_SECTOR_BITS,
+                      BDRV_SECTOR_SIZE, iobuf, 0) < 0) {
             printf("%s: read error in sector %" PRIu64 "\n", __func__, page);
         }
         memset(iobuf, 0xff, ((addr - 1) & 0x1ff) + 1);
-        if (blk_pwrite(s->blk, page << BDRV_SECTOR_BITS, iobuf,
-                       BDRV_SECTOR_SIZE, 0) < 0) {
+        if (blk_pwrite(s->blk, page << BDRV_SECTOR_BITS,
+                       BDRV_SECTOR_SIZE, iobuf, 0) < 0) {
             printf("%s: write error in sector %" PRIu64 "\n", __func__, page);
         }
     }
@@ -772,8 +772,8 @@ static void glue(nand_blk_load_, NAND_PAGE_SIZE)(NANDFlashState *s,
 
     if (s->blk) {
         if (s->mem_oob) {
-            if (blk_pread(s->blk, SECTOR(addr) << BDRV_SECTOR_BITS, s->io,
-                          PAGE_SECTORS << BDRV_SECTOR_BITS) < 0) {
+            if (blk_pread(s->blk, SECTOR(addr) << BDRV_SECTOR_BITS,
+                          PAGE_SECTORS << BDRV_SECTOR_BITS, s->io, 0) < 0) {
                 printf("%s: read error in sector %" PRIu64 "\n",
                                 __func__, SECTOR(addr));
             }
@@ -782,8 +782,9 @@ static void glue(nand_blk_load_, NAND_PAGE_SIZE)(NANDFlashState *s,
                             OOB_SIZE);
             s->ioaddr = s->io + SECTOR_OFFSET(s->addr) + offset;
         } else {
-            if (blk_pread(s->blk, PAGE_START(addr), s->io,
-                          (PAGE_SECTORS + 2) << BDRV_SECTOR_BITS) < 0) {
+            if (blk_pread(s->blk, PAGE_START(addr),
+                          (PAGE_SECTORS + 2) << BDRV_SECTOR_BITS, s->io, 0)
+                < 0) {
                 printf("%s: read error in sector %" PRIu64 "\n",
                                 __func__, PAGE_START(addr) >> 9);
             }

hw/block/onenand.c

@@ -229,8 +229,8 @@ static void onenand_reset(OneNANDState *s, int cold)
         /* Lock the whole flash */
         memset(s->blockwp, ONEN_LOCK_LOCKED, s->blocks);
 
-        if (s->blk_cur && blk_pread(s->blk_cur, 0, s->boot[0],
-                                    8 << BDRV_SECTOR_BITS) < 0) {
+        if (s->blk_cur && blk_pread(s->blk_cur, 0, 8 << BDRV_SECTOR_BITS,
+                                    s->boot[0], 0) < 0) {
             hw_error("%s: Loading the BootRAM failed.\n", __func__);
         }
     }
@@ -249,8 +249,8 @@ static inline int onenand_load_main(OneNANDState *s, int sec, int secn,
     assert(UINT32_MAX >> BDRV_SECTOR_BITS > sec);
     assert(UINT32_MAX >> BDRV_SECTOR_BITS > secn);
     if (s->blk_cur) {
-        return blk_pread(s->blk_cur, sec << BDRV_SECTOR_BITS, dest,
-                         secn << BDRV_SECTOR_BITS) < 0;
+        return blk_pread(s->blk_cur, sec << BDRV_SECTOR_BITS,
+                         secn << BDRV_SECTOR_BITS, dest, 0) < 0;
     } else if (sec + secn > s->secs_cur) {
         return 1;
     }
@@ -274,7 +274,7 @@ static inline int onenand_prog_main(OneNANDState *s, int sec, int secn,
         uint8_t *dp = 0;
         if (s->blk_cur) {
             dp = g_malloc(size);
-            if (!dp || blk_pread(s->blk_cur, offset, dp, size) < 0) {
+            if (!dp || blk_pread(s->blk_cur, offset, size, dp, 0) < 0) {
                 result = 1;
             }
         } else {
@@ -290,7 +290,7 @@ static inline int onenand_prog_main(OneNANDState *s, int sec, int secn,
                 dp[i] &= sp[i];
             }
             if (s->blk_cur) {
-                result = blk_pwrite(s->blk_cur, offset, dp, size, 0) < 0;
+                result = blk_pwrite(s->blk_cur, offset, size, dp, 0) < 0;
             }
         }
         if (dp && s->blk_cur) {
@@ -308,7 +308,7 @@ static inline int onenand_load_spare(OneNANDState *s, int sec, int secn,
 
     if (s->blk_cur) {
         uint32_t offset = (s->secs_cur + (sec >> 5)) << BDRV_SECTOR_BITS;
-        if (blk_pread(s->blk_cur, offset, buf, BDRV_SECTOR_SIZE) < 0) {
+        if (blk_pread(s->blk_cur, offset, BDRV_SECTOR_SIZE, buf, 0) < 0) {
             return 1;
         }
         memcpy(dest, buf + ((sec & 31) << 4), secn << 4);
@@ -333,7 +333,7 @@ static inline int onenand_prog_spare(OneNANDState *s, int sec, int secn,
         if (s->blk_cur) {
             dp = g_malloc(512);
             if (!dp
-                || blk_pread(s->blk_cur, offset, dp, BDRV_SECTOR_SIZE) < 0) {
+                || blk_pread(s->blk_cur, offset, BDRV_SECTOR_SIZE, dp, 0) < 0) {
                 result = 1;
             } else {
                 dpp = dp + ((sec & 31) << 4);
@@ -351,8 +351,8 @@ static inline int onenand_prog_spare(OneNANDState *s, int sec, int secn,
                 dpp[i] &= sp[i];
             }
             if (s->blk_cur) {
-                result = blk_pwrite(s->blk_cur, offset, dp,
-                                    BDRV_SECTOR_SIZE, 0) < 0;
+                result = blk_pwrite(s->blk_cur, offset, BDRV_SECTOR_SIZE, dp,
+                                    0) < 0;
             }
         }
         g_free(dp);
@@ -370,17 +370,17 @@ static inline int onenand_erase(OneNANDState *s, int sec, int num)
     for (; num > 0; num--, sec++) {
         if (s->blk_cur) {
             int erasesec = s->secs_cur + (sec >> 5);
-            if (blk_pwrite(s->blk_cur, sec << BDRV_SECTOR_BITS, blankbuf,
-                           BDRV_SECTOR_SIZE, 0) < 0) {
+            if (blk_pwrite(s->blk_cur, sec << BDRV_SECTOR_BITS,
+                           BDRV_SECTOR_SIZE, blankbuf, 0) < 0) {
                 goto fail;
             }
-            if (blk_pread(s->blk_cur, erasesec << BDRV_SECTOR_BITS, tmpbuf,
-                          BDRV_SECTOR_SIZE) < 0) {
+            if (blk_pread(s->blk_cur, erasesec << BDRV_SECTOR_BITS,
+                          BDRV_SECTOR_SIZE, tmpbuf, 0) < 0) {
                 goto fail;
             }
             memcpy(tmpbuf + ((sec & 31) << 4), blankbuf, 1 << 4);
-            if (blk_pwrite(s->blk_cur, erasesec << BDRV_SECTOR_BITS, tmpbuf,
-                           BDRV_SECTOR_SIZE, 0) < 0) {
+            if (blk_pwrite(s->blk_cur, erasesec << BDRV_SECTOR_BITS,
+                           BDRV_SECTOR_SIZE, tmpbuf, 0) < 0) {
                 goto fail;
             }
         } else {

hw/block/pflash_cfi01.c

@@ -392,8 +392,8 @@ static void pflash_update(PFlashCFI01 *pfl, int offset,
         /* widen to sector boundaries */
         offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
         offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
-        ret = blk_pwrite(pfl->blk, offset, pfl->storage + offset,
-                   offset_end - offset, 0);
+        ret = blk_pwrite(pfl->blk, offset, offset_end - offset,
+                         pfl->storage + offset, 0);
         if (ret < 0) {
             /* TODO set error bit in status */
             error_report("Could not update PFLASH: %s", strerror(-ret));

hw/block/pflash_cfi02.c

@@ -400,8 +400,8 @@ static void pflash_update(PFlashCFI02 *pfl, int offset, int size)
         /* widen to sector boundaries */
         offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
         offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
-        ret = blk_pwrite(pfl->blk, offset, pfl->storage + offset,
-                   offset_end - offset, 0);
+        ret = blk_pwrite(pfl->blk, offset, offset_end - offset,
+                         pfl->storage + offset, 0);
         if (ret < 0) {
             /* TODO set error bit in status */
             error_report("Could not update PFLASH: %s", strerror(-ret));

hw/ide/atapi.c

@@ -98,11 +98,11 @@ cd_read_sector_sync(IDEState *s)
     switch (s->cd_sector_size) {
     case 2048:
         ret = blk_pread(s->blk, (int64_t)s->lba << ATAPI_SECTOR_BITS,
-                        s->io_buffer, ATAPI_SECTOR_SIZE);
+                        ATAPI_SECTOR_SIZE, s->io_buffer, 0);
         break;
     case 2352:
         ret = blk_pread(s->blk, (int64_t)s->lba << ATAPI_SECTOR_BITS,
-                        s->io_buffer + 16, ATAPI_SECTOR_SIZE);
+                        ATAPI_SECTOR_SIZE, s->io_buffer + 16, 0);
         if (ret >= 0) {
             cd_data_to_raw(s->io_buffer, s->lba);
         }

hw/misc/mac_via.c

@@ -351,7 +351,7 @@ static void via1_one_second(void *opaque)
 static void pram_update(MOS6522Q800VIA1State *v1s)
 {
     if (v1s->blk) {
-        if (blk_pwrite(v1s->blk, 0, v1s->PRAM, sizeof(v1s->PRAM), 0) < 0) {
+        if (blk_pwrite(v1s->blk, 0, sizeof(v1s->PRAM), v1s->PRAM, 0) < 0) {
             qemu_log("pram_update: cannot write to file\n");
         }
     }
@@ -1029,8 +1029,8 @@ static void mos6522_q800_via1_realize(DeviceState *dev, Error **errp)
             return;
         }
 
-        len = blk_pread(v1s->blk, 0, v1s->PRAM, sizeof(v1s->PRAM));
-        if (len != sizeof(v1s->PRAM)) {
+        ret = blk_pread(v1s->blk, 0, sizeof(v1s->PRAM), v1s->PRAM, 0);
+        if (ret < 0) {
             error_setg(errp, "can't read PRAM contents");
             return;
         }

hw/misc/sifive_u_otp.c

@@ -64,8 +64,8 @@ static uint64_t sifive_u_otp_read(void *opaque, hwaddr addr, unsigned int size)
             if (s->blk) {
                 int32_t buf;
 
-                if (blk_pread(s->blk, s->pa * SIFIVE_U_OTP_FUSE_WORD, &buf,
-                              SIFIVE_U_OTP_FUSE_WORD) < 0) {
+                if (blk_pread(s->blk, s->pa * SIFIVE_U_OTP_FUSE_WORD,
+                              SIFIVE_U_OTP_FUSE_WORD, &buf, 0) < 0) {
                     error_report("read error index<%d>", s->pa);
                     return 0xff;
                 }
@@ -167,8 +167,8 @@ static void sifive_u_otp_write(void *opaque, hwaddr addr,
             /* write to backend */
             if (s->blk) {
                 if (blk_pwrite(s->blk, s->pa * SIFIVE_U_OTP_FUSE_WORD,
-                               &s->fuse[s->pa], SIFIVE_U_OTP_FUSE_WORD,
-                               0) < 0) {
+                               SIFIVE_U_OTP_FUSE_WORD, &s->fuse[s->pa], 0)
+                    < 0) {
                     error_report("write error index<%d>", s->pa);
                 }
             }
@@ -240,7 +240,7 @@ static void sifive_u_otp_realize(DeviceState *dev, Error **errp)
                 return;
             }
 
-            if (blk_pread(s->blk, 0, s->fuse, filesize) != filesize) {
+            if (blk_pread(s->blk, 0, filesize, s->fuse, 0) < 0) {
                 error_setg(errp, "failed to read the initial flash content");
                 return;
             }
@@ -261,14 +261,14 @@ static void sifive_u_otp_realize(DeviceState *dev, Error **errp)
 
         serial_data = s->serial;
         if (blk_pwrite(s->blk, index * SIFIVE_U_OTP_FUSE_WORD,
-                       &serial_data, SIFIVE_U_OTP_FUSE_WORD, 0) < 0) {
+                       SIFIVE_U_OTP_FUSE_WORD, &serial_data, 0) < 0) {
             error_setg(errp, "failed to write index<%d>", index);
             return;
         }
 
         serial_data = ~(s->serial);
         if (blk_pwrite(s->blk, (index + 1) * SIFIVE_U_OTP_FUSE_WORD,
-                       &serial_data, SIFIVE_U_OTP_FUSE_WORD, 0) < 0) {
+                       SIFIVE_U_OTP_FUSE_WORD, &serial_data, 0) < 0) {
             error_setg(errp, "failed to write index<%d>", index + 1);
             return;
         }

hw/nvram/eeprom_at24c.c

@@ -64,8 +64,8 @@ int at24c_eeprom_event(I2CSlave *s, enum i2c_event event)
     case I2C_START_RECV:
         DPRINTK("clear\n");
         if (ee->blk && ee->changed) {
-            int len = blk_pwrite(ee->blk, 0, ee->mem, ee->rsize, 0);
-            if (len != ee->rsize) {
+            int ret = blk_pwrite(ee->blk, 0, ee->rsize, ee->mem, 0);
+            if (ret < 0) {
                 ERR(TYPE_AT24C_EE
                         " : failed to write backing file\n");
             }
@@ -165,9 +165,9 @@ void at24c_eeprom_reset(DeviceState *state)
     memset(ee->mem, 0, ee->rsize);
 
     if (ee->blk) {
-        int len = blk_pread(ee->blk, 0, ee->mem, ee->rsize);
+        int ret = blk_pread(ee->blk, 0, ee->rsize, ee->mem, 0);
 
-        if (len != ee->rsize) {
+        if (ret < 0) {
             ERR(TYPE_AT24C_EE
                     " : Failed initial sync with backing file\n");
         }

hw/nvram/spapr_nvram.c

@@ -103,7 +103,7 @@ static void rtas_nvram_store(PowerPCCPU *cpu, SpaprMachineState *spapr,
 {
     SpaprNvram *nvram = spapr->nvram;
     hwaddr offset, buffer, len;
-    int alen;
+    int ret;
     void *membuf;
 
     if ((nargs != 3) || (nret != 2)) {
@@ -128,9 +128,9 @@ static void rtas_nvram_store(PowerPCCPU *cpu, SpaprMachineState *spapr,
 
     membuf = cpu_physical_memory_map(buffer, &len, false);
 
-    alen = len;
+    ret = 0;
     if (nvram->blk) {
-        alen = blk_pwrite(nvram->blk, offset, membuf, len, 0);
+        ret = blk_pwrite(nvram->blk, offset, len, membuf, 0);
     }
 
     assert(nvram->buf);
@@ -138,8 +138,8 @@ static void rtas_nvram_store(PowerPCCPU *cpu, SpaprMachineState *spapr,
 
     cpu_physical_memory_unmap(membuf, len, 0, len);
 
-    rtas_st(rets, 0, (alen < len) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
-    rtas_st(rets, 1, (alen < 0) ? 0 : alen);
+    rtas_st(rets, 0, (ret < 0) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
+    rtas_st(rets, 1, (ret < 0) ? 0 : len);
 }
 
 static void spapr_nvram_realize(SpaprVioDevice *dev, Error **errp)
@@ -179,9 +179,9 @@ static void spapr_nvram_realize(SpaprVioDevice *dev, Error **errp)
     }
 
     if (nvram->blk) {
-        int alen = blk_pread(nvram->blk, 0, nvram->buf, nvram->size);
+        ret = blk_pread(nvram->blk, 0, nvram->size, nvram->buf, 0);
 
-        if (alen != nvram->size) {
+        if (ret < 0) {
             error_setg(errp, "can't read spapr-nvram contents");
             return;
         }
@@ -224,7 +224,7 @@ static void postload_update_cb(void *opaque, bool running, RunState state)
     qemu_del_vm_change_state_handler(nvram->vmstate);
     nvram->vmstate = NULL;
 
-    blk_pwrite(nvram->blk, 0, nvram->buf, nvram->size, 0);
+    blk_pwrite(nvram->blk, 0, nvram->size, nvram->buf, 0);
 }
 
 static int spapr_nvram_post_load(void *opaque, int version_id)

hw/nvram/xlnx-bbram.c

@@ -124,7 +124,7 @@ static void bbram_bdrv_read(XlnxBBRam *s, Error **errp)
                     blk_name(s->blk));
     }
 
-    if (blk_pread(s->blk, 0, ram, nr) < 0) {
+    if (blk_pread(s->blk, 0, nr, ram, 0) < 0) {
         error_setg(errp,
                    "%s: Failed to read %u bytes from BBRAM backstore.",
                    blk_name(s->blk), nr);
@@ -159,7 +159,7 @@ static void bbram_bdrv_sync(XlnxBBRam *s, uint64_t hwaddr)
     }
 
     offset = hwaddr - A_BBRAM_0;
-    rc = blk_pwrite(s->blk, offset, &le32, 4, 0);
+    rc = blk_pwrite(s->blk, offset, 4, &le32, 0);
     if (rc < 0) {
         bbram_bdrv_error(s, rc, g_strdup_printf("write to offset %u", offset));
     }

hw/nvram/xlnx-efuse.c

@@ -77,7 +77,7 @@ static int efuse_bdrv_read(XlnxEFuse *s, Error **errp)
                     blk_name(s->blk));
     }
 
-    if (blk_pread(s->blk, 0, ram, nr) < 0) {
+    if (blk_pread(s->blk, 0, nr, ram, 0) < 0) {
         error_setg(errp, "%s: Failed to read %u bytes from eFUSE backstore.",
                    blk_name(s->blk), nr);
         return -1;
@@ -105,7 +105,7 @@ static void efuse_bdrv_sync(XlnxEFuse *s, unsigned int bit)
     le32 = cpu_to_le32(xlnx_efuse_get_row(s, bit));
 
     row_offset = (bit / 32) * 4;
-    if (blk_pwrite(s->blk, row_offset, &le32, 4, 0) < 0) {
+    if (blk_pwrite(s->blk, row_offset, 4, &le32, 0) < 0) {
         error_report("%s: Failed to write offset %u of eFUSE backstore.",
                      blk_name(s->blk), row_offset);
     }

hw/ppc/pnv_pnor.c

@@ -44,8 +44,8 @@ static void pnv_pnor_update(PnvPnor *s, int offset, int size)
     offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
     offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
 
-    ret = blk_pwrite(s->blk, offset, s->storage + offset,
-                     offset_end - offset, 0);
+    ret = blk_pwrite(s->blk, offset, offset_end - offset, s->storage + offset,
+                     0);
     if (ret < 0) {
         error_report("Could not update PNOR offset=0x%" PRIx32" : %s", offset,
                      strerror(-ret));
@@ -99,7 +99,7 @@ static void pnv_pnor_realize(DeviceState *dev, Error **errp)
 
         s->storage = blk_blockalign(s->blk, s->size);
 
-        if (blk_pread(s->blk, 0, s->storage, s->size) != s->size) {
+        if (blk_pread(s->blk, 0, s->size, s->storage, 0) < 0) {
             error_setg(errp, "failed to read the initial flash content");
             return;
         }

hw/sd/sd.c

@@ -752,7 +752,7 @@ void sd_set_cb(SDState *sd, qemu_irq readonly, qemu_irq insert)
 static void sd_blk_read(SDState *sd, uint64_t addr, uint32_t len)
 {
     trace_sdcard_read_block(addr, len);
-    if (!sd->blk || blk_pread(sd->blk, addr, sd->data, len) < 0) {
+    if (!sd->blk || blk_pread(sd->blk, addr, len, sd->data, 0) < 0) {
         fprintf(stderr, "sd_blk_read: read error on host side\n");
     }
 }
@@ -760,7 +760,7 @@ static void sd_blk_read(SDState *sd, uint64_t addr, uint32_t len)
 static void sd_blk_write(SDState *sd, uint64_t addr, uint32_t len)
 {
     trace_sdcard_write_block(addr, len);
-    if (!sd->blk || blk_pwrite(sd->blk, addr, sd->data, len, 0) < 0) {
+    if (!sd->blk || blk_pwrite(sd->blk, addr, len, sd->data, 0) < 0) {
         fprintf(stderr, "sd_blk_write: write error on host side\n");
     }
 }

include/block/block-io.h

@@ -39,14 +39,22 @@
  * to catch when they are accidentally called by the wrong API.
  */
 
-int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
-                       int64_t bytes, BdrvRequestFlags flags);
+int generated_co_wrapper bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
+                                            int64_t bytes,
+                                            BdrvRequestFlags flags);
 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags);
-int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int64_t bytes);
-int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf,
-                int64_t bytes);
-int bdrv_pwrite_sync(BdrvChild *child, int64_t offset,
-                     const void *buf, int64_t bytes);
+int generated_co_wrapper bdrv_pread(BdrvChild *child, int64_t offset,
+                                    int64_t bytes, void *buf,
+                                    BdrvRequestFlags flags);
+int generated_co_wrapper bdrv_pwrite(BdrvChild *child, int64_t offset,
+                                     int64_t bytes, const void *buf,
+                                     BdrvRequestFlags flags);
+int generated_co_wrapper bdrv_pwrite_sync(BdrvChild *child, int64_t offset,
+                                          int64_t bytes, const void *buf,
+                                          BdrvRequestFlags flags);
+int coroutine_fn bdrv_co_pwrite_sync(BdrvChild *child, int64_t offset,
+                                     int64_t bytes, const void *buf,
+                                     BdrvRequestFlags flags);
 /*
  * Efficiently zero a region of the disk image.  Note that this is a regular
  * I/O request like read or write and should have a reasonable size.  This

include/block/block_int-io.h

@@ -56,7 +56,7 @@ int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child,
     QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
 
 static inline int coroutine_fn bdrv_co_pread(BdrvChild *child,
-    int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags)
+    int64_t offset, int64_t bytes, void *buf, BdrvRequestFlags flags)
 {
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
     IO_CODE();
@@ -65,7 +65,7 @@ static inline int coroutine_fn bdrv_co_pread(BdrvChild *child,
 }
 
 static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child,
-    int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags)
+    int64_t offset, int64_t bytes, const void *buf, BdrvRequestFlags flags)
 {
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
     IO_CODE();

include/crypto/block.h

@@ -29,24 +29,24 @@ typedef struct QCryptoBlock QCryptoBlock;
 /* See also QCryptoBlockFormat, QCryptoBlockCreateOptions
  * and QCryptoBlockOpenOptions in qapi/crypto.json */
 
-typedef ssize_t (*QCryptoBlockReadFunc)(QCryptoBlock *block,
-                                        size_t offset,
-                                        uint8_t *buf,
-                                        size_t buflen,
-                                        void *opaque,
-                                        Error **errp);
+typedef int (*QCryptoBlockReadFunc)(QCryptoBlock *block,
+                                    size_t offset,
+                                    uint8_t *buf,
+                                    size_t buflen,
+                                    void *opaque,
+                                    Error **errp);
 
-typedef ssize_t (*QCryptoBlockInitFunc)(QCryptoBlock *block,
-                                        size_t headerlen,
-                                        void *opaque,
-                                        Error **errp);
+typedef int (*QCryptoBlockInitFunc)(QCryptoBlock *block,
+                                    size_t headerlen,
+                                    void *opaque,
+                                    Error **errp);
 
-typedef ssize_t (*QCryptoBlockWriteFunc)(QCryptoBlock *block,
-                                         size_t offset,
-                                         const uint8_t *buf,
-                                         size_t buflen,
-                                         void *opaque,
-                                         Error **errp);
+typedef int (*QCryptoBlockWriteFunc)(QCryptoBlock *block,
+                                     size_t offset,
+                                     const uint8_t *buf,
+                                     size_t buflen,
+                                     void *opaque,
+                                     Error **errp);
 
 /**
  * qcrypto_block_has_format:

include/sysemu/block-backend-io.h

@@ -101,60 +101,79 @@ int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in,
  * the "I/O or GS" API.
  */
 
-int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int bytes);
-int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int bytes,
-               BdrvRequestFlags flags);
+int generated_co_wrapper blk_pread(BlockBackend *blk, int64_t offset,
+                                   int64_t bytes, void *buf,
+                                   BdrvRequestFlags flags);
+int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes,
+                              void *buf, BdrvRequestFlags flags);
+
+int generated_co_wrapper blk_preadv(BlockBackend *blk, int64_t offset,
+                                    int64_t bytes, QEMUIOVector *qiov,
+                                    BdrvRequestFlags flags);
 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
                                int64_t bytes, QEMUIOVector *qiov,
                                BdrvRequestFlags flags);
-int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset,
-                                     int64_t bytes,
-                                     QEMUIOVector *qiov, size_t qiov_offset,
+
+int generated_co_wrapper blk_preadv_part(BlockBackend *blk, int64_t offset,
+                                         int64_t bytes, QEMUIOVector *qiov,
+                                         size_t qiov_offset,
+                                         BdrvRequestFlags flags);
+int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset,
+                                    int64_t bytes, QEMUIOVector *qiov,
+                                    size_t qiov_offset, BdrvRequestFlags flags);
+
+int generated_co_wrapper blk_pwrite(BlockBackend *blk, int64_t offset,
+                                    int64_t bytes, const void *buf,
+                                    BdrvRequestFlags flags);
+int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
+                               const void *buf, BdrvRequestFlags flags);
+
+int generated_co_wrapper blk_pwritev(BlockBackend *blk, int64_t offset,
+                                     int64_t bytes, QEMUIOVector *qiov,
                                      BdrvRequestFlags flags);
 int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset,
                                 int64_t bytes, QEMUIOVector *qiov,
                                 BdrvRequestFlags flags);
 
-static inline int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset,
-                                            int64_t bytes, void *buf,
-                                            BdrvRequestFlags flags)
-{
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_OR_GS_CODE();
+int generated_co_wrapper blk_pwritev_part(BlockBackend *blk, int64_t offset,
+                                          int64_t bytes, QEMUIOVector *qiov,
+                                          size_t qiov_offset,
+                                          BdrvRequestFlags flags);
+int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset,
+                                     int64_t bytes,
+                                     QEMUIOVector *qiov, size_t qiov_offset,
+                                     BdrvRequestFlags flags);
 
-    assert(bytes <= SIZE_MAX);
+int generated_co_wrapper blk_pwrite_compressed(BlockBackend *blk,
+                                               int64_t offset, int64_t bytes,
+                                               const void *buf);
+int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset,
+                                          int64_t bytes, const void *buf);
 
-    return blk_co_preadv(blk, offset, bytes, &qiov, flags);
-}
-
-static inline int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset,
-                                             int64_t bytes, void *buf,
-                                             BdrvRequestFlags flags)
-{
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_OR_GS_CODE();
-
-    assert(bytes <= SIZE_MAX);
-
-    return blk_co_pwritev(blk, offset, bytes, &qiov, flags);
-}
+int generated_co_wrapper blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                                           int64_t bytes,
+                                           BdrvRequestFlags flags);
+int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                                      int64_t bytes, BdrvRequestFlags flags);
 
+int generated_co_wrapper blk_pdiscard(BlockBackend *blk, int64_t offset,
+                                      int64_t bytes);
 int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
                                  int64_t bytes);
 
+int generated_co_wrapper blk_flush(BlockBackend *blk);
 int coroutine_fn blk_co_flush(BlockBackend *blk);
-int blk_flush(BlockBackend *blk);
 
-int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
+int generated_co_wrapper blk_ioctl(BlockBackend *blk, unsigned long int req,
+                                   void *buf);
+int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req,
+                              void *buf);
 
-int blk_pwrite_compressed(BlockBackend *blk, int64_t offset, const void *buf,
-                          int64_t bytes);
-int blk_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes);
-int blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
-                      int64_t bytes, BdrvRequestFlags flags);
-int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
-                                      int64_t bytes, BdrvRequestFlags flags);
-int blk_truncate(BlockBackend *blk, int64_t offset, bool exact,
-                 PreallocMode prealloc, BdrvRequestFlags flags, Error **errp);
+int generated_co_wrapper blk_truncate(BlockBackend *blk, int64_t offset,
+                                      bool exact, PreallocMode prealloc,
+                                      BdrvRequestFlags flags, Error **errp);
+int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact,
+                                 PreallocMode prealloc, BdrvRequestFlags flags,
+                                 Error **errp);
 
 #endif /* BLOCK_BACKEND_IO_H */

migration/block.c

@@ -568,8 +568,8 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
                 bmds_set_aio_inflight(bmds, sector, nr_sectors, 1);
                 blk_mig_unlock();
             } else {
-                ret = blk_pread(bmds->blk, sector * BDRV_SECTOR_SIZE, blk->buf,
-                                nr_sectors * BDRV_SECTOR_SIZE);
+                ret = blk_pread(bmds->blk, sector * BDRV_SECTOR_SIZE,
+                                nr_sectors * BDRV_SECTOR_SIZE, blk->buf, 0);
                 if (ret < 0) {
                     goto error;
                 }
@@ -976,8 +976,8 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
                                                 cluster_size,
                                                 BDRV_REQ_MAY_UNMAP);
                     } else {
-                        ret = blk_pwrite(blk, cur_addr, cur_buf,
-                                         cluster_size, 0);
+                        ret = blk_pwrite(blk, cur_addr, cluster_size, cur_buf,
+                                         0);
                     }
                     if (ret < 0) {
                         break;

nbd/server.c

@@ -2039,8 +2039,8 @@ static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client,
             stl_be_p(&chunk.length, pnum);
             ret = nbd_co_send_iov(client, iov, 1, errp);
         } else {
-            ret = blk_pread(exp->common.blk, offset + progress,
-                            data + progress, pnum);
+            ret = blk_pread(exp->common.blk, offset + progress, pnum,
+                            data + progress, 0);
             if (ret < 0) {
                 error_setg_errno(errp, -ret, "reading from file failed");
                 break;
@@ -2444,7 +2444,7 @@ static coroutine_fn int nbd_do_cmd_read(NBDClient *client, NBDRequest *request,
                                        data, request->len, errp);
     }
 
-    ret = blk_pread(exp->common.blk, request->from, data, request->len);
+    ret = blk_pread(exp->common.blk, request->from, request->len, data, 0);
     if (ret < 0) {
         return nbd_send_generic_reply(client, request->handle, ret,
                                       "reading from file failed", errp);
@@ -2511,7 +2511,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
         if (request->flags & NBD_CMD_FLAG_FUA) {
             flags |= BDRV_REQ_FUA;
         }
-        ret = blk_pwrite(exp->common.blk, request->from, data, request->len,
+        ret = blk_pwrite(exp->common.blk, request->from, request->len, data,
                          flags);
         return nbd_send_generic_reply(client, request->handle, ret,
                                       "writing to file failed", errp);

qemu-img.c

@@ -1309,7 +1309,7 @@ static int check_empty_sectors(BlockBackend *blk, int64_t offset,
     int ret = 0;
     int64_t idx;
 
-    ret = blk_pread(blk, offset, buffer, bytes);
+    ret = blk_pread(blk, offset, bytes, buffer, 0);
     if (ret < 0) {
         error_report("Error while reading offset %" PRId64 " of %s: %s",
                      offset, filename, strerror(-ret));
@@ -1526,7 +1526,7 @@ static int img_compare(int argc, char **argv)
                 int64_t pnum;
 
                 chunk = MIN(chunk, IO_BUF_SIZE);
-                ret = blk_pread(blk1, offset, buf1, chunk);
+                ret = blk_pread(blk1, offset, chunk, buf1, 0);
                 if (ret < 0) {
                     error_report("Error while reading offset %" PRId64
                                  " of %s: %s",
@@ -1534,7 +1534,7 @@ static int img_compare(int argc, char **argv)
                     ret = 4;
                     goto out;
                 }
-                ret = blk_pread(blk2, offset, buf2, chunk);
+                ret = blk_pread(blk2, offset, chunk, buf2, 0);
                 if (ret < 0) {
                     error_report("Error while reading offset %" PRId64
                                  " of %s: %s",
@@ -2114,7 +2114,7 @@ static int convert_do_copy(ImgConvertState *s)
 
     if (s->compressed && !s->ret) {
         /* signal EOF to align */
-        ret = blk_pwrite_compressed(s->target, 0, NULL, 0);
+        ret = blk_pwrite_compressed(s->target, 0, 0, NULL);
         if (ret < 0) {
             return ret;
         }
@@ -3779,7 +3779,7 @@ static int img_rebase(int argc, char **argv)
                     n = old_backing_size - offset;
                 }
 
-                ret = blk_pread(blk_old_backing, offset, buf_old, n);
+                ret = blk_pread(blk_old_backing, offset, n, buf_old, 0);
                 if (ret < 0) {
                     error_report("error while reading from old backing file");
                     goto out;
@@ -3793,7 +3793,7 @@ static int img_rebase(int argc, char **argv)
                     n = new_backing_size - offset;
                 }
 
-                ret = blk_pread(blk_new_backing, offset, buf_new, n);
+                ret = blk_pread(blk_new_backing, offset, n, buf_new, 0);
                 if (ret < 0) {
                     error_report("error while reading from new backing file");
                     goto out;
@@ -3812,8 +3812,8 @@ static int img_rebase(int argc, char **argv)
                     if (buf_old_is_zero) {
                         ret = blk_pwrite_zeroes(blk, offset + written, pnum, 0);
                     } else {
-                        ret = blk_pwrite(blk, offset + written,
-                                         buf_old + written, pnum, 0);
+                        ret = blk_pwrite(blk, offset + written, pnum,
+                                         buf_old + written, 0);
                     }
                     if (ret < 0) {
                         error_report("Error while writing to COW image: %s",
@@ -5120,30 +5120,23 @@ static int img_dd(int argc, char **argv)
     in.buf = g_new(uint8_t, in.bsz);
 
     for (out_pos = 0; in_pos < size; block_count++) {
-        int in_ret, out_ret;
+        int bytes = (in_pos + in.bsz > size) ? size - in_pos : in.bsz;
 
-        if (in_pos + in.bsz > size) {
-            in_ret = blk_pread(blk1, in_pos, in.buf, size - in_pos);
-        } else {
-            in_ret = blk_pread(blk1, in_pos, in.buf, in.bsz);
-        }
-        if (in_ret < 0) {
+        ret = blk_pread(blk1, in_pos, bytes, in.buf, 0);
+        if (ret < 0) {
             error_report("error while reading from input image file: %s",
-                         strerror(-in_ret));
-            ret = -1;
+                         strerror(-ret));
             goto out;
         }
-        in_pos += in_ret;
+        in_pos += bytes;
 
-        out_ret = blk_pwrite(blk2, out_pos, in.buf, in_ret, 0);
-
-        if (out_ret < 0) {
+        ret = blk_pwrite(blk2, out_pos, bytes, in.buf, 0);
+        if (ret < 0) {
             error_report("error while writing to output image file: %s",
-                         strerror(-out_ret));
-            ret = -1;
+                         strerror(-ret));
             goto out;
         }
-        out_pos += out_ret;
+        out_pos += bytes;
     }
 
 out:

qemu-io-cmds.c

@@ -541,28 +541,34 @@ fail:
 static int do_pread(BlockBackend *blk, char *buf, int64_t offset,
                     int64_t bytes, int64_t *total)
 {
+    int ret;
+
     if (bytes > INT_MAX) {
         return -ERANGE;
     }
 
-    *total = blk_pread(blk, offset, (uint8_t *)buf, bytes);
-    if (*total < 0) {
-        return *total;
+    ret = blk_pread(blk, offset, bytes, (uint8_t *)buf, 0);
+    if (ret < 0) {
+        return ret;
     }
+    *total = bytes;
     return 1;
 }
 
 static int do_pwrite(BlockBackend *blk, char *buf, int64_t offset,
                      int64_t bytes, int flags, int64_t *total)
 {
+    int ret;
+
     if (bytes > INT_MAX) {
         return -ERANGE;
     }
 
-    *total = blk_pwrite(blk, offset, (uint8_t *)buf, bytes, flags);
-    if (*total < 0) {
-        return *total;
+    ret = blk_pwrite(blk, offset, bytes, (uint8_t *)buf, flags);
+    if (ret < 0) {
+        return ret;
     }
+    *total = bytes;
     return 1;
 }
 
@@ -625,7 +631,7 @@ static int do_write_compressed(BlockBackend *blk, char *buf, int64_t offset,
         return -ERANGE;
     }
 
-    ret = blk_pwrite_compressed(blk, offset, buf, bytes);
+    ret = blk_pwrite_compressed(blk, offset, bytes, buf);
     if (ret < 0) {
         return ret;
     }

softmmu/vl.c

@@ -1522,13 +1522,18 @@ machine_parse_property_opt(QemuOptsList *opts_list, const char *propname,
 }
 
 static const char *pid_file;
-static Notifier qemu_unlink_pidfile_notifier;
+struct UnlinkPidfileNotifier {
+    Notifier notifier;
+    char *pid_file_realpath;
+};
+static struct UnlinkPidfileNotifier qemu_unlink_pidfile_notifier;
 
 static void qemu_unlink_pidfile(Notifier *n, void *data)
 {
-    if (pid_file) {
-        unlink(pid_file);
-    }
+    struct UnlinkPidfileNotifier *upn;
+
+    upn = DO_UPCAST(struct UnlinkPidfileNotifier, notifier, n);
+    unlink(upn->pid_file_realpath);
 }
 
 static const QEMUOption *lookup_opt(int argc, char **argv,
@@ -2431,13 +2436,30 @@ static void qemu_maybe_daemonize(const char *pid_file)
     os_daemonize();
     rcu_disable_atfork();
 
-    if (pid_file && !qemu_write_pidfile(pid_file, &err)) {
-        error_reportf_err(err, "cannot create PID file: ");
-        exit(1);
-    }
+    if (pid_file) {
+        char *pid_file_realpath = NULL;
 
-    qemu_unlink_pidfile_notifier.notify = qemu_unlink_pidfile;
-    qemu_add_exit_notifier(&qemu_unlink_pidfile_notifier);
+        if (!qemu_write_pidfile(pid_file, &err)) {
+            error_reportf_err(err, "cannot create PID file: ");
+            exit(1);
+        }
+
+        pid_file_realpath = g_malloc0(PATH_MAX);
+        if (!realpath(pid_file, pid_file_realpath)) {
+            error_report("cannot resolve PID file path: %s: %s",
+                         pid_file, strerror(errno));
+            unlink(pid_file);
+            exit(1);
+        }
+
+        qemu_unlink_pidfile_notifier = (struct UnlinkPidfileNotifier) {
+            .notifier = {
+                .notify = qemu_unlink_pidfile,
+            },
+            .pid_file_realpath = pid_file_realpath,
+        };
+        qemu_add_exit_notifier(&qemu_unlink_pidfile_notifier.notifier);
+    }
 }
 
 static void qemu_init_displays(void)

storage-daemon/qemu-storage-daemon.c

@@ -61,6 +61,7 @@
 #include "trace/control.h"
 
 static const char *pid_file;
+static char *pid_file_realpath;
 static volatile bool exit_requested = false;
 
 void qemu_system_killed(int signal, pid_t pid)
@@ -296,7 +297,11 @@ static void process_options(int argc, char *argv[], bool pre_init_pass)
             }
         case OPTION_DAEMONIZE:
             if (os_set_daemonize(true) < 0) {
-                error_report("--daemonize not supported in this build");
+                /*
+                 * --daemonize is parsed before monitor_init_globals_core(), so
+                 * error_report() does not work yet
+                 */
+                fprintf(stderr, "--daemonize not supported in this build\n");
                 exit(EXIT_FAILURE);
             }
             break;
@@ -359,7 +364,7 @@ static void process_options(int argc, char *argv[], bool pre_init_pass)
 
 static void pid_file_cleanup(void)
 {
-    unlink(pid_file);
+    unlink(pid_file_realpath);
 }
 
 static void pid_file_init(void)
@@ -375,6 +380,14 @@ static void pid_file_init(void)
         exit(EXIT_FAILURE);
     }
 
+    pid_file_realpath = g_malloc(PATH_MAX);
+    if (!realpath(pid_file, pid_file_realpath)) {
+        error_report("cannot resolve PID file path: %s: %s",
+                     pid_file, strerror(errno));
+        unlink(pid_file);
+        exit(EXIT_FAILURE);
+    }
+
     atexit(pid_file_cleanup);
 }
 

tests/qemu-iotests/108

@@ -60,6 +60,11 @@ if sudo -n losetup &>/dev/null; then
 else
     loopdev=false
 
+    # Check for usable FUSE in the host environment:
+    if test ! -c "/dev/fuse"; then
+        _notrun 'No passwordless sudo nor usable /dev/fuse'
+    fi
+
     # QSD --export fuse will either yield "Parameter 'id' is missing"
     # or "Invalid parameter 'fuse'", depending on whether there is
     # FUSE support or not.

tests/qemu-iotests/223.out

@@ -93,7 +93,7 @@ exports available: 3
  export: 'n2'
   description: some text
   size:  4194304
-  flags: 0xced ( flush fua trim zeroes df cache fast-zero )
+  flags: 0xded ( flush fua trim zeroes df multi cache fast-zero )
   min block: 1
   opt block: 4096
   max block: 33554432
@@ -212,7 +212,7 @@ exports available: 3
  export: 'n2'
   description: some text
   size:  4194304
-  flags: 0xced ( flush fua trim zeroes df cache fast-zero )
+  flags: 0xded ( flush fua trim zeroes df multi cache fast-zero )
   min block: 1
   opt block: 4096
   max block: 33554432

tests/qemu-iotests/307.out

@@ -83,7 +83,7 @@ exports available: 2
  export: 'export1'
   description: This is the writable second export
   size:  67108864
-  flags: 0xced ( flush fua trim zeroes df cache fast-zero )
+  flags: 0xded ( flush fua trim zeroes df multi cache fast-zero )
   min block: XXX
   opt block: XXX
   max block: XXX
@@ -109,7 +109,7 @@ exports available: 1
  export: 'export1'
   description: This is the writable second export
   size:  67108864
-  flags: 0xced ( flush fua trim zeroes df cache fast-zero )
+  flags: 0xded ( flush fua trim zeroes df multi cache fast-zero )
   min block: XXX
   opt block: XXX
   max block: XXX

tests/qemu-iotests/mypy.ini

@@ -9,4 +9,4 @@ no_implicit_optional = True
 scripts_are_modules = True
 warn_redundant_casts = True
 warn_unused_configs = True
-warn_unused_ignores = True
+warn_unused_ignores = False

tests/unit/test-block-iothread.c

@@ -88,11 +88,11 @@ static void test_sync_op_pread(BdrvChild *c)
     int ret;
 
     /* Success */
-    ret = bdrv_pread(c, 0, buf, sizeof(buf));
-    g_assert_cmpint(ret, ==, 512);
+    ret = bdrv_pread(c, 0, sizeof(buf), buf, 0);
+    g_assert_cmpint(ret, ==, 0);
 
     /* Early error: Negative offset */
-    ret = bdrv_pread(c, -2, buf, sizeof(buf));
+    ret = bdrv_pread(c, -2, sizeof(buf), buf, 0);
     g_assert_cmpint(ret, ==, -EIO);
 }
 
@@ -102,11 +102,11 @@ static void test_sync_op_pwrite(BdrvChild *c)
     int ret;
 
     /* Success */
-    ret = bdrv_pwrite(c, 0, buf, sizeof(buf));
-    g_assert_cmpint(ret, ==, 512);
+    ret = bdrv_pwrite(c, 0, sizeof(buf), buf, 0);
+    g_assert_cmpint(ret, ==, 0);
 
     /* Early error: Negative offset */
-    ret = bdrv_pwrite(c, -2, buf, sizeof(buf));
+    ret = bdrv_pwrite(c, -2, sizeof(buf), buf, 0);
     g_assert_cmpint(ret, ==, -EIO);
 }
 
@@ -116,11 +116,11 @@ static void test_sync_op_blk_pread(BlockBackend *blk)
     int ret;
 
     /* Success */
-    ret = blk_pread(blk, 0, buf, sizeof(buf));
-    g_assert_cmpint(ret, ==, 512);
+    ret = blk_pread(blk, 0, sizeof(buf), buf, 0);
+    g_assert_cmpint(ret, ==, 0);
 
     /* Early error: Negative offset */
-    ret = blk_pread(blk, -2, buf, sizeof(buf));
+    ret = blk_pread(blk, -2, sizeof(buf), buf, 0);
     g_assert_cmpint(ret, ==, -EIO);
 }
 
@@ -130,11 +130,98 @@ static void test_sync_op_blk_pwrite(BlockBackend *blk)
     int ret;
 
     /* Success */
-    ret = blk_pwrite(blk, 0, buf, sizeof(buf), 0);
-    g_assert_cmpint(ret, ==, 512);
+    ret = blk_pwrite(blk, 0, sizeof(buf), buf, 0);
+    g_assert_cmpint(ret, ==, 0);
 
     /* Early error: Negative offset */
-    ret = blk_pwrite(blk, -2, buf, sizeof(buf), 0);
+    ret = blk_pwrite(blk, -2, sizeof(buf), buf, 0);
+    g_assert_cmpint(ret, ==, -EIO);
+}
+
+static void test_sync_op_blk_preadv(BlockBackend *blk)
+{
+    uint8_t buf[512];
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, sizeof(buf));
+    int ret;
+
+    /* Success */
+    ret = blk_preadv(blk, 0, sizeof(buf), &qiov, 0);
+    g_assert_cmpint(ret, ==, 0);
+
+    /* Early error: Negative offset */
+    ret = blk_preadv(blk, -2, sizeof(buf), &qiov, 0);
+    g_assert_cmpint(ret, ==, -EIO);
+}
+
+static void test_sync_op_blk_pwritev(BlockBackend *blk)
+{
+    uint8_t buf[512] = { 0 };
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, sizeof(buf));
+    int ret;
+
+    /* Success */
+    ret = blk_pwritev(blk, 0, sizeof(buf), &qiov, 0);
+    g_assert_cmpint(ret, ==, 0);
+
+    /* Early error: Negative offset */
+    ret = blk_pwritev(blk, -2, sizeof(buf), &qiov, 0);
+    g_assert_cmpint(ret, ==, -EIO);
+}
+
+static void test_sync_op_blk_preadv_part(BlockBackend *blk)
+{
+    uint8_t buf[512];
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, sizeof(buf));
+    int ret;
+
+    /* Success */
+    ret = blk_preadv_part(blk, 0, sizeof(buf), &qiov, 0, 0);
+    g_assert_cmpint(ret, ==, 0);
+
+    /* Early error: Negative offset */
+    ret = blk_preadv_part(blk, -2, sizeof(buf), &qiov, 0, 0);
+    g_assert_cmpint(ret, ==, -EIO);
+}
+
+static void test_sync_op_blk_pwritev_part(BlockBackend *blk)
+{
+    uint8_t buf[512] = { 0 };
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, sizeof(buf));
+    int ret;
+
+    /* Success */
+    ret = blk_pwritev_part(blk, 0, sizeof(buf), &qiov, 0, 0);
+    g_assert_cmpint(ret, ==, 0);
+
+    /* Early error: Negative offset */
+    ret = blk_pwritev_part(blk, -2, sizeof(buf), &qiov, 0, 0);
+    g_assert_cmpint(ret, ==, -EIO);
+}
+
+static void test_sync_op_blk_pwrite_compressed(BlockBackend *blk)
+{
+    uint8_t buf[512] = { 0 };
+    int ret;
+
+    /* Late error: Not supported */
+    ret = blk_pwrite_compressed(blk, 0, sizeof(buf), buf);
+    g_assert_cmpint(ret, ==, -ENOTSUP);
+
+    /* Early error: Negative offset */
+    ret = blk_pwrite_compressed(blk, -2, sizeof(buf), buf);
+    g_assert_cmpint(ret, ==, -EIO);
+}
+
+static void test_sync_op_blk_pwrite_zeroes(BlockBackend *blk)
+{
+    int ret;
+
+    /* Success */
+    ret = blk_pwrite_zeroes(blk, 0, 512, 0);
+    g_assert_cmpint(ret, ==, 0);
+
+    /* Early error: Negative offset */
+    ret = blk_pwrite_zeroes(blk, -2, 512, 0);
     g_assert_cmpint(ret, ==, -EIO);
 }
 
@@ -211,6 +298,19 @@ static void test_sync_op_truncate(BdrvChild *c)
     c->bs->open_flags |= BDRV_O_RDWR;
 }
 
+static void test_sync_op_blk_truncate(BlockBackend *blk)
+{
+    int ret;
+
+    /* Normal success path */
+    ret = blk_truncate(blk, 65536, false, PREALLOC_MODE_OFF, 0, NULL);
+    g_assert_cmpint(ret, ==, 0);
+
+    /* Early error: Negative offset */
+    ret = blk_truncate(blk, -2, false, PREALLOC_MODE_OFF, 0, NULL);
+    g_assert_cmpint(ret, ==, -EINVAL);
+}
+
 static void test_sync_op_block_status(BdrvChild *c)
 {
     int ret;
@@ -301,6 +401,30 @@ const SyncOpTest sync_op_tests[] = {
         .name   = "/sync-op/pwrite",
         .fn     = test_sync_op_pwrite,
         .blkfn  = test_sync_op_blk_pwrite,
+    }, {
+        .name   = "/sync-op/preadv",
+        .fn     = NULL,
+        .blkfn  = test_sync_op_blk_preadv,
+    }, {
+        .name   = "/sync-op/pwritev",
+        .fn     = NULL,
+        .blkfn  = test_sync_op_blk_pwritev,
+    }, {
+        .name   = "/sync-op/preadv_part",
+        .fn     = NULL,
+        .blkfn  = test_sync_op_blk_preadv_part,
+    }, {
+        .name   = "/sync-op/pwritev_part",
+        .fn     = NULL,
+        .blkfn  = test_sync_op_blk_pwritev_part,
+    }, {
+        .name   = "/sync-op/pwrite_compressed",
+        .fn     = NULL,
+        .blkfn  = test_sync_op_blk_pwrite_compressed,
+    }, {
+        .name   = "/sync-op/pwrite_zeroes",
+        .fn     = NULL,
+        .blkfn  = test_sync_op_blk_pwrite_zeroes,
     }, {
         .name   = "/sync-op/load_vmstate",
         .fn     = test_sync_op_load_vmstate,
@@ -314,6 +438,7 @@ const SyncOpTest sync_op_tests[] = {
     }, {
         .name   = "/sync-op/truncate",
         .fn     = test_sync_op_truncate,
+        .blkfn  = test_sync_op_blk_truncate,
     }, {
         .name   = "/sync-op/block_status",
         .fn     = test_sync_op_block_status,
@@ -349,7 +474,9 @@ static void test_sync_op(const void *opaque)
 
     blk_set_aio_context(blk, ctx, &error_abort);
     aio_context_acquire(ctx);
-    t->fn(c);
+    if (t->fn) {
+        t->fn(c);
+    }
     if (t->blkfn) {
         t->blkfn(blk);
     }

tests/unit/test-crypto-block.c

@@ -188,12 +188,12 @@ static struct QCryptoBlockTestData {
 };
 
 
-static ssize_t test_block_read_func(QCryptoBlock *block,
-                                    size_t offset,
-                                    uint8_t *buf,
-                                    size_t buflen,
-                                    void *opaque,
-                                    Error **errp)
+static int test_block_read_func(QCryptoBlock *block,
+                                size_t offset,
+                                uint8_t *buf,
+                                size_t buflen,
+                                void *opaque,
+                                Error **errp)
 {
     Buffer *header = opaque;
 
@@ -201,14 +201,14 @@ static ssize_t test_block_read_func(QCryptoBlock *block,
 
     memcpy(buf, header->buffer + offset, buflen);
 
-    return buflen;
+    return 0;
 }
 
 
-static ssize_t test_block_init_func(QCryptoBlock *block,
-                                    size_t headerlen,
-                                    void *opaque,
-                                    Error **errp)
+static int test_block_init_func(QCryptoBlock *block,
+                                size_t headerlen,
+                                void *opaque,
+                                Error **errp)
 {
     Buffer *header = opaque;
 
@@ -216,16 +216,16 @@ static ssize_t test_block_init_func(QCryptoBlock *block,
 
     buffer_reserve(header, headerlen);
 
-    return headerlen;
+    return 0;
 }
 
 
-static ssize_t test_block_write_func(QCryptoBlock *block,
-                                     size_t offset,
-                                     const uint8_t *buf,
-                                     size_t buflen,
-                                     void *opaque,
-                                     Error **errp)
+static int test_block_write_func(QCryptoBlock *block,
+                                 size_t offset,
+                                 const uint8_t *buf,
+                                 size_t buflen,
+                                 void *opaque,
+                                 Error **errp)
 {
     Buffer *header = opaque;
 
@@ -234,7 +234,7 @@ static ssize_t test_block_write_func(QCryptoBlock *block,
     memcpy(header->buffer + offset, buf, buflen);
     header->offset = offset + buflen;
 
-    return buflen;
+    return 0;
 }