block: switch blk_write_compressed() to byte-based interface

This is a preparatory patch, which continues the general trend of the
transition to the byte-based interfaces. bdrv_check_request() and
blk_check_request() are no longer used, thus we can remove them.

Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/block-backend.c

@@ -743,21 +743,6 @@ static int blk_check_byte_request(BlockBackend *blk, int64_t offset,
     return 0;
 }
 
-static int blk_check_request(BlockBackend *blk, int64_t sector_num,
-                             int nb_sectors)
-{
-    if (sector_num < 0 || sector_num > INT64_MAX / BDRV_SECTOR_SIZE) {
-        return -EIO;
-    }
-
-    if (nb_sectors < 0 || nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {
-        return -EIO;
-    }
-
-    return blk_check_byte_request(blk, sector_num * BDRV_SECTOR_SIZE,
-                                  nb_sectors * BDRV_SECTOR_SIZE);
-}
-
 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
                                unsigned int bytes, QEMUIOVector *qiov,
                                BdrvRequestFlags flags)
@@ -1500,15 +1485,15 @@ int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
                           flags | BDRV_REQ_ZERO_WRITE);
 }
 
-int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
-                         const uint8_t *buf, int nb_sectors)
+int blk_pwrite_compressed(BlockBackend *blk, int64_t offset, const void *buf,
+                          int count)
 {
-    int ret = blk_check_request(blk, sector_num, nb_sectors);
+    int ret = blk_check_byte_request(blk, offset, count);
     if (ret < 0) {
         return ret;
     }
 
-    return bdrv_write_compressed(blk_bs(blk), sector_num, buf, nb_sectors);
+    return bdrv_pwrite_compressed(blk_bs(blk), offset, buf, count);
 }
 
 int blk_truncate(BlockBackend *blk, int64_t offset)

block/io.c

@@ -540,17 +540,6 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
     return 0;
 }
 
-static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
-                              int nb_sectors)
-{
-    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
-        return -EIO;
-    }
-
-    return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
-                                   nb_sectors * BDRV_SECTOR_SIZE);
-}
-
 typedef struct RwCo {
     BdrvChild *child;
     int64_t offset;
@@ -1879,8 +1868,8 @@ int bdrv_is_allocated_above(BlockDriverState *top,
     return 0;
 }
 
-int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
-                          const uint8_t *buf, int nb_sectors)
+int bdrv_pwrite_compressed(BlockDriverState *bs, int64_t offset,
+                           const void *buf, int bytes)
 {
     BlockDriver *drv = bs->drv;
     int ret;
@@ -1891,14 +1880,17 @@ int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
     if (!drv->bdrv_write_compressed) {
         return -ENOTSUP;
     }
-    ret = bdrv_check_request(bs, sector_num, nb_sectors);
+    ret = bdrv_check_byte_request(bs, offset, bytes);
     if (ret < 0) {
         return ret;
     }
 
     assert(QLIST_EMPTY(&bs->dirty_bitmaps));
+    assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
+    assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
 
-    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
+    return drv->bdrv_write_compressed(bs, offset >> BDRV_SECTOR_BITS, buf,
+                                      bytes >> BDRV_SECTOR_BITS);
 }
 
 typedef struct BdrvVmstateCo {