[Qemu-devel] [PATCH 03/17] block: Switch BlockRequest to byte-based

[Eric Blake <eblake@redhat.com>]

BlockRequest is the internal struct used by bdrv_aio_*.  At the
moment, all such calls were sector-based, but we will eventually
convert to byte-based; start by changing the internal variables
to be byte-based.  No change to behavior, although the read and
write code can now go byte-based through more of the stack.

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 block/io.c | 64 +++++++++++++++++++++++++++++++-------------------------------
 1 file changed, 32 insertions(+), 32 deletions(-)

diff --git a/block/io.c b/block/io.c
index 305e5c5..d442ce7 100644
--- a/block/io.c
+++ b/block/io.c
@@ -33,14 +33,13 @@

 #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */

-static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
-                                         int64_t sector_num,
-                                         QEMUIOVector *qiov,
-                                         int nb_sectors,
-                                         BdrvRequestFlags flags,
-                                         BlockCompletionFunc *cb,
-                                         void *opaque,
-                                         bool is_write);
+static BlockAIOCB *bdrv_co_aio_prw_vector(BlockDriverState *bs,
+                                          int64_t offset,
+                                          QEMUIOVector *qiov,
+                                          BdrvRequestFlags flags,
+                                          BlockCompletionFunc *cb,
+                                          void *opaque,
+                                          bool is_write);
 static void coroutine_fn bdrv_co_do_rw(void *opaque);
 static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs,
     int64_t offset, int count, BdrvRequestFlags flags);
@@ -2010,8 +2009,9 @@ BlockAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
 {
     trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque);

-    return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0,
-                                 cb, opaque, false);
+    assert(nb_sectors << BDRV_SECTOR_BITS == qiov->size);
+    return bdrv_co_aio_prw_vector(bs, sector_num << BDRV_SECTOR_BITS, qiov, 0,
+                                  cb, opaque, false);
 }

 BlockAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
@@ -2020,8 +2020,9 @@ BlockAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
 {
     trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque);

-    return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0,
-                                 cb, opaque, true);
+    assert(nb_sectors << BDRV_SECTOR_BITS == qiov->size);
+    return bdrv_co_aio_prw_vector(bs, sector_num << BDRV_SECTOR_BITS, qiov, 0,
+                                  cb, opaque, true);
 }

 void bdrv_aio_cancel(BlockAIOCB *acb)
@@ -2057,8 +2058,8 @@ typedef struct BlockRequest {
     union {
         /* Used during read, write, trim */
         struct {
-            int64_t sector;
-            int nb_sectors;
+            int64_t offset;
+            int bytes;
             int flags;
             QEMUIOVector *qiov;
         };
@@ -2122,24 +2123,23 @@ static void coroutine_fn bdrv_co_do_rw(void *opaque)
     BlockDriverState *bs = acb->common.bs;

     if (!acb->is_write) {
-        acb->req.error = bdrv_co_do_readv(bs, acb->req.sector,
-            acb->req.nb_sectors, acb->req.qiov, acb->req.flags);
+        acb->req.error = bdrv_co_preadv(bs, acb->req.offset,
+            acb->req.qiov->size, acb->req.qiov, acb->req.flags);
     } else {
-        acb->req.error = bdrv_co_do_writev(bs, acb->req.sector,
-            acb->req.nb_sectors, acb->req.qiov, acb->req.flags);
+        acb->req.error = bdrv_co_pwritev(bs, acb->req.offset,
+            acb->req.qiov->size, acb->req.qiov, acb->req.flags);
     }

     bdrv_co_complete(acb);
 }

-static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
-                                         int64_t sector_num,
-                                         QEMUIOVector *qiov,
-                                         int nb_sectors,
-                                         BdrvRequestFlags flags,
-                                         BlockCompletionFunc *cb,
-                                         void *opaque,
-                                         bool is_write)
+static BlockAIOCB *bdrv_co_aio_prw_vector(BlockDriverState *bs,
+                                          int64_t offset,
+                                          QEMUIOVector *qiov,
+                                          BdrvRequestFlags flags,
+                                          BlockCompletionFunc *cb,
+                                          void *opaque,
+                                          bool is_write)
 {
     Coroutine *co;
     BlockAIOCBCoroutine *acb;
@@ -2147,8 +2147,7 @@ static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
     acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
     acb->need_bh = true;
     acb->req.error = -EINPROGRESS;
-    acb->req.sector = sector_num;
-    acb->req.nb_sectors = nb_sectors;
+    acb->req.offset = offset;
     acb->req.qiov = qiov;
     acb->req.flags = flags;
     acb->is_write = is_write;
@@ -2193,8 +2192,8 @@ static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque)
     BlockAIOCBCoroutine *acb = opaque;
     BlockDriverState *bs = acb->common.bs;

-    acb->req.error = bdrv_co_pdiscard(bs, acb->req.sector << BDRV_SECTOR_BITS,
-                                      acb->req.nb_sectors << BDRV_SECTOR_BITS);
+    acb->req.error = bdrv_co_pdiscard(bs, acb->req.offset,
+                                      acb->req.qiov->size);
     bdrv_co_complete(acb);
 }

@@ -2204,14 +2203,15 @@ BlockAIOCB *bdrv_aio_discard(BlockDriverState *bs,
 {
     Coroutine *co;
     BlockAIOCBCoroutine *acb;
+    QEMUIOVector qiov = { .size = nb_sectors << BDRV_SECTOR_BITS, };

     trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque);

     acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
     acb->need_bh = true;
     acb->req.error = -EINPROGRESS;
-    acb->req.sector = sector_num;
-    acb->req.nb_sectors = nb_sectors;
+    acb->req.offset = sector_num << BDRV_SECTOR_BITS;
+    acb->req.qiov = &qiov;
     co = qemu_coroutine_create(bdrv_aio_discard_co_entry);
     qemu_coroutine_enter(co, acb);

-- 
2.5.5