4347 ZPL can use dmu_tx_assign(TXG_WAIT)
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>

*** 1467,1477 ****
           */
          if (end <= zp->z_size) {
                  zfs_range_unlock(rl);
                  return (0);
          }
- top:
          tx = dmu_tx_create(zfsvfs->z_os);
          dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
          zfs_sa_upgrade_txholds(tx, zp);
          if (end > zp->z_blksz &&
              (!ISP2(zp->z_blksz) || zp->z_blksz < zfsvfs->z_max_blksz)) {
--- 1467,1476 ----
*** 1487,1504 ****
                  dmu_tx_hold_write(tx, zp->z_id, 0, newblksz);
          } else {
                  newblksz = 0;
          }
  
!         error = dmu_tx_assign(tx, TXG_NOWAIT);
          if (error) {
-                 if (error == ERESTART) {
-                         dmu_tx_wait(tx);
                          dmu_tx_abort(tx);
-                         goto top;
-                 }
-                 dmu_tx_abort(tx);
                  zfs_range_unlock(rl);
                  return (error);
          }
  
          if (newblksz)
--- 1486,1498 ----
                  dmu_tx_hold_write(tx, zp->z_id, 0, newblksz);
          } else {
                  newblksz = 0;
          }
  
!         error = dmu_tx_assign(tx, TXG_WAIT);
          if (error) {
                  dmu_tx_abort(tx);
                  zfs_range_unlock(rl);
                  return (error);
          }
  
          if (newblksz)
*** 1590,1611 ****
          error = dmu_free_long_range(zfsvfs->z_os, zp->z_id, end,  -1);
          if (error) {
                  zfs_range_unlock(rl);
                  return (error);
          }
- top:
          tx = dmu_tx_create(zfsvfs->z_os);
          dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
          zfs_sa_upgrade_txholds(tx, zp);
!         error = dmu_tx_assign(tx, TXG_NOWAIT);
          if (error) {
-                 if (error == ERESTART) {
-                         dmu_tx_wait(tx);
                          dmu_tx_abort(tx);
-                         goto top;
-                 }
-                 dmu_tx_abort(tx);
                  zfs_range_unlock(rl);
                  return (error);
          }
  
          zp->z_size = end;
--- 1584,1599 ----
          error = dmu_free_long_range(zfsvfs->z_os, zp->z_id, end,  -1);
          if (error) {
                  zfs_range_unlock(rl);
                  return (error);
          }
          tx = dmu_tx_create(zfsvfs->z_os);
          dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
          zfs_sa_upgrade_txholds(tx, zp);
!         error = dmu_tx_assign(tx, TXG_WAIT);
          if (error) {
                  dmu_tx_abort(tx);
                  zfs_range_unlock(rl);
                  return (error);
          }
  
          zp->z_size = end;
*** 1707,1724 ****
                  return (error);
  log:
          tx = dmu_tx_create(zfsvfs->z_os);
          dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
          zfs_sa_upgrade_txholds(tx, zp);
!         error = dmu_tx_assign(tx, TXG_NOWAIT);
          if (error) {
-                 if (error == ERESTART) {
-                         dmu_tx_wait(tx);
                          dmu_tx_abort(tx);
-                         goto log;
-                 }
-                 dmu_tx_abort(tx);
                  return (error);
          }
  
          SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL, mtime, 16);
          SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL, ctime, 16);
--- 1695,1707 ----
                  return (error);
  log:
          tx = dmu_tx_create(zfsvfs->z_os);
          dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
          zfs_sa_upgrade_txholds(tx, zp);
!         error = dmu_tx_assign(tx, TXG_WAIT);
          if (error) {
                  dmu_tx_abort(tx);
                  return (error);
          }
  
          SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL, mtime, 16);
          SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL, ctime, 16);