fs/dax: remove wmb_pmem()

Flushing posted-write queues is now deferred to REQ_FLUSH context, or
otherwise handled by an ADR event at the platform level.

Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/fs/dax.c b/fs/dax.c
index 761495b..434f421 100644 (file)
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -147,7 +147,7 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter,
                      struct buffer_head *bh)
 {
        loff_t pos = start, max = start, bh_max = start;
-       bool hole = false, need_wmb = false;
+       bool hole = false;
        struct block_device *bdev = NULL;
        int rw = iov_iter_rw(iter), rc;
        long map_len = 0;
@@ -213,7 +213,6 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter,
 
                if (iov_iter_rw(iter) == WRITE) {
                        len = copy_from_iter_pmem(dax.addr, max - pos, iter);
-                       need_wmb = true;
                } else if (!hole)
                        len = copy_to_iter((void __force *) dax.addr, max - pos,
                                        iter);
@@ -230,8 +229,6 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter,
                        dax.addr += len;
        }
 
-       if (need_wmb)
-               wmb_pmem();
        dax_unmap_atomic(bdev, &dax);
 
        return (pos == start) ? rc : pos - start;
@@ -783,7 +780,6 @@ int dax_writeback_mapping_range(struct address_space *mapping,
                                return ret;
                }
        }
-       wmb_pmem();
        return 0;
 }
 EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
@@ -1227,7 +1223,6 @@ int __dax_zero_page_range(struct block_device *bdev, sector_t sector,
                if (dax_map_atomic(bdev, &dax) < 0)
                        return PTR_ERR(dax.addr);
                clear_pmem(dax.addr + offset, length);
-               wmb_pmem();
                dax_unmap_atomic(bdev, &dax);
        }
        return 0;