block: Rename blk_write_zeroes()

Commit 983a1600 changed the semantics of blk_write_zeroes() to
be byte-based rather than sector-based, but did not change the
name, which is an open invitation for other code to misuse the
function.  Renaming to pwrite_zeroes() makes it more in line
with other byte-based interfaces, and will help make it easier
to track which remaining write_zeroes interfaces still need
conversion.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

block/block-backend.c

@@ -855,8 +855,8 @@ int blk_pread_unthrottled(BlockBackend *blk, int64_t offset, uint8_t *buf,
     return ret;
 }
 
-int blk_write_zeroes(BlockBackend *blk, int64_t offset,
-                     int count, BdrvRequestFlags flags)
+int blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                      int count, BdrvRequestFlags flags)
 {
     return blk_prw(blk, offset, NULL, count, blk_write_entry,
                    flags | BDRV_REQ_ZERO_WRITE);
@@ -971,9 +971,9 @@ static void blk_aio_write_entry(void *opaque)
     blk_aio_complete(acb);
 }
 
-BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t offset,
-                                 int count, BdrvRequestFlags flags,
-                                 BlockCompletionFunc *cb, void *opaque)
+BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                                  int count, BdrvRequestFlags flags,
+                                  BlockCompletionFunc *cb, void *opaque)
 {
     return blk_aio_prwv(blk, offset, count, NULL, blk_aio_write_entry,
                         flags | BDRV_REQ_ZERO_WRITE, cb, opaque);
@@ -1462,8 +1462,8 @@ 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 offset,
-                                     int count, BdrvRequestFlags flags)
+int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                                      int count, BdrvRequestFlags flags)
 {
     return blk_co_pwritev(blk, offset, count, NULL,
                           flags | BDRV_REQ_ZERO_WRITE);

block/parallels.c

@@ -517,8 +517,8 @@ static int parallels_create(const char *filename, QemuOpts *opts, Error **errp)
     if (ret < 0) {
         goto exit;
     }
-    ret = blk_write_zeroes(file, BDRV_SECTOR_SIZE,
-                           (bat_sectors - 1) << BDRV_SECTOR_BITS, 0);
+    ret = blk_pwrite_zeroes(file, BDRV_SECTOR_SIZE,
+                            (bat_sectors - 1) << BDRV_SECTOR_BITS, 0);
     if (ret < 0) {
         goto exit;
     }

hw/scsi/scsi-disk.c

@@ -1780,7 +1780,7 @@ static void scsi_disk_emulate_write_same(SCSIDiskReq *r, uint8_t *inbuf)
         block_acct_start(blk_get_stats(s->qdev.conf.blk), &r->acct,
                          nb_sectors * s->qdev.blocksize,
                         BLOCK_ACCT_WRITE);
-        r->req.aiocb = blk_aio_write_zeroes(s->qdev.conf.blk,
+        r->req.aiocb = blk_aio_pwrite_zeroes(s->qdev.conf.blk,
                                 r->req.cmd.lba * s->qdev.blocksize,
                                 nb_sectors * s->qdev.blocksize,
                                 flags, scsi_aio_complete, r);

include/sysemu/block-backend.h

@@ -113,11 +113,11 @@ void *blk_get_attached_dev(BlockBackend *blk);
 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque);
 int blk_pread_unthrottled(BlockBackend *blk, int64_t offset, uint8_t *buf,
                           int count);
-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_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                      int count, BdrvRequestFlags flags);
+BlockAIOCB *blk_aio_pwrite_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,
                BdrvRequestFlags flags);
@@ -195,8 +195,8 @@ 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 offset,
-                                     int count, BdrvRequestFlags flags);
+int coroutine_fn blk_co_pwrite_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);

qemu-img.c

@@ -1606,8 +1606,8 @@ 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 << BDRV_SECTOR_BITS,
-                                   n << BDRV_SECTOR_BITS, 0);
+            ret = blk_pwrite_zeroes(s->target, sector_num << BDRV_SECTOR_BITS,
+                                    n << BDRV_SECTOR_BITS, 0);
             if (ret < 0) {
                 return ret;
             }

qemu-io-cmds.c

@@ -451,12 +451,12 @@ typedef struct {
     bool done;
 } CoWriteZeroes;
 
-static void coroutine_fn co_write_zeroes_entry(void *opaque)
+static void coroutine_fn co_pwrite_zeroes_entry(void *opaque)
 {
     CoWriteZeroes *data = opaque;
 
-    data->ret = blk_co_write_zeroes(data->blk, data->offset, data->count,
-                                    data->flags);
+    data->ret = blk_co_pwrite_zeroes(data->blk, data->offset, data->count,
+                                     data->flags);
     data->done = true;
     if (data->ret < 0) {
         *data->total = data->ret;
@@ -466,8 +466,8 @@ static void coroutine_fn co_write_zeroes_entry(void *opaque)
     *data->total = data->count;
 }
 
-static int do_co_write_zeroes(BlockBackend *blk, int64_t offset, int64_t count,
-                              int flags, int64_t *total)
+static int do_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
+                               int64_t count, int flags, int64_t *total)
 {
     Coroutine *co;
     CoWriteZeroes data = {
@@ -483,7 +483,7 @@ static int do_co_write_zeroes(BlockBackend *blk, int64_t offset, int64_t count,
         return -ERANGE;
     }
 
-    co = qemu_coroutine_create(co_write_zeroes_entry);
+    co = qemu_coroutine_create(co_pwrite_zeroes_entry);
     qemu_coroutine_enter(co, &data);
     while (!data.done) {
         aio_poll(blk_get_aio_context(blk), true);
@@ -901,7 +901,7 @@ static void write_help(void)
 " -C, -- report statistics in a machine parsable format\n"
 " -q, -- quiet mode, do not show I/O statistics\n"
 " -u, -- with -z, allow unmapping\n"
-" -z, -- write zeroes using blk_co_write_zeroes\n"
+" -z, -- write zeroes using blk_co_pwrite_zeroes\n"
 "\n");
 }
 
@@ -1033,7 +1033,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
     if (bflag) {
         cnt = do_save_vmstate(blk, buf, offset, count, &total);
     } else if (zflag) {
-        cnt = do_co_write_zeroes(blk, offset, count, flags, &total);
+        cnt = do_co_pwrite_zeroes(blk, offset, count, flags, &total);
     } else if (cflag) {
         cnt = do_write_compressed(blk, buf, offset, count, &total);
     } else {
@@ -1376,7 +1376,7 @@ static void aio_write_help(void)
 " -i, -- treat request as invalid, for exercising stats\n"
 " -q, -- quiet mode, do not show I/O statistics\n"
 " -u, -- with -z, allow unmapping\n"
-" -z, -- write zeroes using blk_aio_write_zeroes\n"
+" -z, -- write zeroes using blk_aio_pwrite_zeroes\n"
 "\n");
 }
 
@@ -1475,8 +1475,8 @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv)
         }
 
         ctx->qiov.size = count;
-        blk_aio_write_zeroes(blk, ctx->offset, count, flags, aio_write_done,
-                             ctx);
+        blk_aio_pwrite_zeroes(blk, ctx->offset, count, flags, aio_write_done,
+                              ctx);
     } else {
         nr_iov = argc - optind;
         ctx->buf = create_iovec(blk, &ctx->qiov, &argv[optind], nr_iov,