qcow2: rename two QCowAIOCB members

The n member is not very descriptive and very hard to grep, rename it to cur_nr_sectors to better indicate what it is used for. Also rename nb_sectors to remaining_sectors as that is what it is used for.

Signed-off-by Christoph Hellwig<[email protected]>

Index: qemu/block/qcow2.c
===================================================================

block/qcow2.c +31 -29

@@ -332,8 +332,8 @@ typedef struct QCowAIOCB {
      QEMUIOVector *qiov;
      uint8_t *buf;
      void *orig_buf;
-    int nb_sectors;
-    int n;
+    int remaining_sectors;
+    int cur_nr_sectors;	/* number of sectors in current iteration */
      uint64_t cluster_offset;
      uint8_t *cluster_data;
      BlockDriverAIOCB *hd_aiocb;

@@ -399,38 +399,38 @@ static void qcow_aio_read_cb(void *opaqu
      } else {
          if (s->crypt_method) {
              qcow2_encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf,
-                            acb->n, 0,
+                            acb->cur_nr_sectors, 0,
                              &s->aes_decrypt_key);
          }
      }
 
-    acb->nb_sectors -= acb->n;
-    acb->sector_num += acb->n;
-    acb->buf += acb->n * 512;
+    acb->remaining_sectors -= acb->cur_nr_sectors;
+    acb->sector_num += acb->cur_nr_sectors;
+    acb->buf += acb->cur_nr_sectors * 512;
 
-    if (acb->nb_sectors == 0) {
+    if (acb->remaining_sectors == 0) {
          /* request completed */
          ret = 0;
          goto done;
      }
 
      /* prepare next AIO request */
-    acb->n = acb->nb_sectors;
-    acb->cluster_offset =
-        qcow2_get_cluster_offset(bs, acb->sector_num<<  9,&acb->n);
+    acb->cur_nr_sectors = acb->remaining_sectors;
+    acb->cluster_offset = qcow2_get_cluster_offset(bs, acb->sector_num<<  9,
+&acb->cur_nr_sectors);
      index_in_cluster = acb->sector_num&  (s->cluster_sectors - 1);
 
      if (!acb->cluster_offset) {
          if (bs->backing_hd) {
              /* read from the base image */
              n1 = qcow2_backing_read1(bs->backing_hd, acb->sector_num,
-                               acb->buf, acb->n);
+                               acb->buf, acb->cur_nr_sectors);
              if (n1>  0) {
                  acb->hd_iov.iov_base = (void *)acb->buf;
-                acb->hd_iov.iov_len = acb->n * 512;
+                acb->hd_iov.iov_len = acb->cur_nr_sectors * 512;
                  qemu_iovec_init_external(&acb->hd_qiov,&acb->hd_iov, 1);
                  acb->hd_aiocb = bdrv_aio_readv(bs->backing_hd, acb->sector_num,
-&acb->hd_qiov, acb->n,
+&acb->hd_qiov, acb->cur_nr_sectors,
  				    qcow_aio_read_cb, acb);
                  if (acb->hd_aiocb == NULL)
                      goto done;

@@ -441,7 +441,7 @@ static void qcow_aio_read_cb(void *opaqu
              }
          } else {
              /* Note: in this case, no need to wait */
-            memset(acb->buf, 0, 512 * acb->n);
+            memset(acb->buf, 0, 512 * acb->cur_nr_sectors);
              ret = qcow_schedule_bh(qcow_aio_read_bh, acb);
              if (ret<  0)
                  goto done;

@@ -450,8 +450,8 @@ static void qcow_aio_read_cb(void *opaqu
          /* add AIO support for compressed blocks ? */
          if (qcow2_decompress_cluster(s, acb->cluster_offset)<  0)
              goto done;
-        memcpy(acb->buf,
-               s->cluster_cache + index_in_cluster * 512, 512 * acb->n);
+        memcpy(acb->buf, s->cluster_cache + index_in_cluster * 512,
+               512 * acb->cur_nr_sectors);
          ret = qcow_schedule_bh(qcow_aio_read_bh, acb);
          if (ret<  0)
              goto done;

@@ -462,11 +462,12 @@ static void qcow_aio_read_cb(void *opaqu
          }
 
          acb->hd_iov.iov_base = (void *)acb->buf;
-        acb->hd_iov.iov_len = acb->n * 512;
+        acb->hd_iov.iov_len = acb->cur_nr_sectors * 512;
          qemu_iovec_init_external(&acb->hd_qiov,&acb->hd_iov, 1);
          acb->hd_aiocb = bdrv_aio_readv(s->hd,
                              (acb->cluster_offset>>  9) + index_in_cluster,
-&acb->hd_qiov, acb->n, qcow_aio_read_cb, acb);
+&acb->hd_qiov, acb->cur_nr_sectors,
+                            qcow_aio_read_cb, acb);
          if (acb->hd_aiocb == NULL)
              goto done;
      }

@@ -500,8 +501,8 @@ static QCowAIOCB *qcow_aio_setup(BlockDr
      } else {
          acb->buf = (uint8_t *)qiov->iov->iov_base;
      }
-    acb->nb_sectors = nb_sectors;
-    acb->n = 0;
+    acb->remaining_sectors = nb_sectors;
+    acb->cur_nr_sectors = 0;
      acb->cluster_offset = 0;
      acb->l2meta.nb_clusters = 0;
      QLIST_INIT(&acb->l2meta.dependent_requests);

@@ -569,25 +570,26 @@ static void qcow_aio_write_cb(void *opaq
      if (ret<  0)
          goto done;
 
-    acb->nb_sectors -= acb->n;
-    acb->sector_num += acb->n;
-    acb->buf += acb->n * 512;
+    acb->remaining_sectors -= acb->cur_nr_sectors;
+    acb->sector_num += acb->cur_nr_sectors;
+    acb->buf += acb->cur_nr_sectors * 512;
 
-    if (acb->nb_sectors == 0) {
+    if (acb->remaining_sectors == 0) {
          /* request completed */
          ret = 0;
          goto done;
      }
 
      index_in_cluster = acb->sector_num&  (s->cluster_sectors - 1);
-    n_end = index_in_cluster + acb->nb_sectors;
+    n_end = index_in_cluster + acb->remaining_sectors;
      if (s->crypt_method&&
          n_end>  QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors)
          n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors;
 
      acb->cluster_offset = qcow2_alloc_cluster_offset(bs, acb->sector_num<<  9,
                                            index_in_cluster,
-                                          n_end,&acb->n,&acb->l2meta);
+                                          n_end,&acb->cur_nr_sectors,
+&acb->l2meta);
 
      /* Need to wait for another request? If so, we are done for now. */
      if (!acb->cluster_offset&&  acb->l2meta.depends_on != NULL) {

@@ -606,17 +608,17 @@ static void qcow_aio_write_cb(void *opaq
                                               s->cluster_size);
          }
          qcow2_encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf,
-                        acb->n, 1,&s->aes_encrypt_key);
+                        acb->cur_nr_sectors, 1,&s->aes_encrypt_key);
          src_buf = acb->cluster_data;
      } else {
          src_buf = acb->buf;
      }
      acb->hd_iov.iov_base = (void *)src_buf;
-    acb->hd_iov.iov_len = acb->n * 512;
+    acb->hd_iov.iov_len = acb->cur_nr_sectors * 512;
      qemu_iovec_init_external(&acb->hd_qiov,&acb->hd_iov, 1);
      acb->hd_aiocb = bdrv_aio_writev(s->hd,
                                      (acb->cluster_offset>>  9) + index_in_cluster,
-&acb->hd_qiov, acb->n,
+&acb->hd_qiov, acb->cur_nr_sectors,
                                      qcow_aio_write_cb, acb);
      if (acb->hd_aiocb == NULL)
          goto done;