[Qemu-devel] [PATCH v6 04/20] block: Switch blk_*write_zeroes() to byte interface

[Eric Blake <eblake@redhat.com>]

Sector-based blk_write() should die; convert the one-off
variant blk_write_zeroes() to use an offset/count interface
instead.  Likewise for blk_co_write_zeroes() and
blk_aio_write_zeroes().

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 include/sysemu/block-backend.h | 12 ++++++------
 block/block-backend.c          | 33 +++++++++++----------------------
 block/parallels.c              |  3 ++-
 hw/scsi/scsi-disk.c            |  4 ++--
 qemu-img.c                     |  3 ++-
 qemu-io-cmds.c                 |  6 ++----
 6 files changed, 25 insertions(+), 36 deletions(-)

diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
index 662a106..851376b 100644
--- a/include/sysemu/block-backend.h
+++ b/include/sysemu/block-backend.h
@@ -96,10 +96,10 @@ int blk_pread_unthrottled(BlockBackend *blk, int64_t offset, uint8_t *buf,
                           int count);
 int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf,
               int nb_sectors);
-int blk_write_zeroes(BlockBackend *blk, int64_t sector_num,
-                     int nb_sectors, BdrvRequestFlags flags);
-BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num,
-                                 int nb_sectors, BdrvRequestFlags flags,
+int blk_write_zeroes(BlockBackend *blk, int64_t offset,
+                     int count, BdrvRequestFlags flags);
+BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t offset,
+                                 int count, BdrvRequestFlags flags,
                                  BlockCompletionFunc *cb, void *opaque);
 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count);
 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count,
@@ -179,8 +179,8 @@ int blk_get_open_flags_from_root_state(BlockBackend *blk);

 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
                   BlockCompletionFunc *cb, void *opaque);
-int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num,
-                                     int nb_sectors, BdrvRequestFlags flags);
+int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t offset,
+                                     int count, BdrvRequestFlags flags);
 int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
                          const uint8_t *buf, int nb_sectors);
 int blk_truncate(BlockBackend *blk, int64_t offset);
diff --git a/block/block-backend.c b/block/block-backend.c
index e5a8a07..f8f88a6 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -814,11 +814,11 @@ int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf,
                   blk_write_entry, 0);
 }

-int blk_write_zeroes(BlockBackend *blk, int64_t sector_num,
-                     int nb_sectors, BdrvRequestFlags flags)
+int blk_write_zeroes(BlockBackend *blk, int64_t offset,
+                     int count, BdrvRequestFlags flags)
 {
-    return blk_rw(blk, sector_num, NULL, nb_sectors, blk_write_entry,
-                  flags | BDRV_REQ_ZERO_WRITE);
+    return blk_prw(blk, offset, NULL, count, blk_write_entry,
+                   flags | BDRV_REQ_ZERO_WRITE);
 }

 static void error_callback_bh(void *opaque)
@@ -930,18 +930,12 @@ static void blk_aio_write_entry(void *opaque)
     blk_aio_complete(acb);
 }

-BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num,
-                                 int nb_sectors, BdrvRequestFlags flags,
+BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t offset,
+                                 int count, BdrvRequestFlags flags,
                                  BlockCompletionFunc *cb, void *opaque)
 {
-    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
-        return blk_abort_aio_request(blk, cb, opaque, -EINVAL);
-    }
-
-    return blk_aio_prwv(blk, sector_num << BDRV_SECTOR_BITS,
-                        nb_sectors << BDRV_SECTOR_BITS, NULL,
-                        blk_aio_write_entry, flags | BDRV_REQ_ZERO_WRITE,
-                        cb, opaque);
+    return blk_aio_prwv(blk, offset, count, NULL, blk_aio_write_entry,
+                        flags | BDRV_REQ_ZERO_WRITE, cb, opaque);
 }

 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count)
@@ -1444,15 +1438,10 @@ void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
     return qemu_aio_get(aiocb_info, blk_bs(blk), cb, opaque);
 }

-int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num,
-                                     int nb_sectors, BdrvRequestFlags flags)
+int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t offset,
+                                     int count, BdrvRequestFlags flags)
 {
-    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
-        return -EINVAL;
-    }
-
-    return blk_co_pwritev(blk, sector_num << BDRV_SECTOR_BITS,
-                          nb_sectors << BDRV_SECTOR_BITS, NULL,
+    return blk_co_pwritev(blk, offset, count, NULL,
                           flags | BDRV_REQ_ZERO_WRITE);
 }

diff --git a/block/parallels.c b/block/parallels.c
index 2d8bc87..cddbfc4 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -516,7 +516,8 @@ static int parallels_create(const char *filename, QemuOpts *opts, Error **errp)
     if (ret < 0) {
         goto exit;
     }
-    ret = blk_write_zeroes(file, 1, bat_sectors - 1, 0);
+    ret = blk_write_zeroes(file, BDRV_SECTOR_SIZE,
+                           (bat_sectors - 1) << BDRV_SECTOR_BITS, 0);
     if (ret < 0) {
         goto exit;
     }
diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index c3ce54a..1335392 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -1781,8 +1781,8 @@ static void scsi_disk_emulate_write_same(SCSIDiskReq *r, uint8_t *inbuf)
                          nb_sectors * s->qdev.blocksize,
                         BLOCK_ACCT_WRITE);
         r->req.aiocb = blk_aio_write_zeroes(s->qdev.conf.blk,
-                                r->req.cmd.lba * (s->qdev.blocksize / 512),
-                                nb_sectors * (s->qdev.blocksize / 512),
+                                r->req.cmd.lba * s->qdev.blocksize,
+                                nb_sectors * s->qdev.blocksize,
                                 flags, scsi_aio_complete, r);
         return;
     }
diff --git a/qemu-img.c b/qemu-img.c
index 46f2a6d..76430a8 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1589,7 +1589,8 @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors,
             if (s->has_zero_init) {
                 break;
             }
-            ret = blk_write_zeroes(s->target, sector_num, n, 0);
+            ret = blk_write_zeroes(s->target, sector_num << BDRV_SECTOR_BITS,
+                                   n << BDRV_SECTOR_BITS, 0);
             if (ret < 0) {
                 return ret;
             }
diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index e26e543..a3e3982 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -494,8 +494,7 @@ static void coroutine_fn co_write_zeroes_entry(void *opaque)
 {
     CoWriteZeroes *data = opaque;

-    data->ret = blk_co_write_zeroes(data->blk, data->offset / BDRV_SECTOR_SIZE,
-                                    data->count / BDRV_SECTOR_SIZE, 0);
+    data->ret = blk_co_write_zeroes(data->blk, data->offset, data->count, 0);
     data->done = true;
     if (data->ret < 0) {
         *data->total = data->ret;
@@ -1703,8 +1702,7 @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv)
         }

         ctx->qiov.size = count;
-        blk_aio_write_zeroes(blk, ctx->offset >> 9, count >> 9, 0,
-                             aio_write_done, ctx);
+        blk_aio_write_zeroes(blk, ctx->offset, count, 0, aio_write_done, ctx);
     } else {
         nr_iov = argc - optind;
         ctx->buf = create_iovec(blk, &ctx->qiov, &argv[optind], nr_iov,
-- 
2.5.5