[nacked] dax-enable-iostat-for-read-write.patch removed from -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: DAX: enable iostat for read/write
has been removed from the -mm tree.  Its filename was
     dax-enable-iostat-for-read-write.patch

This patch was dropped because it was nacked

------------------------------------------------------
From: Toshi Kani <toshi.kani@hpe.com>
Subject: DAX: enable iostat for read/write

DAX IO path does not support iostat, but its metadata IO path does. 
Therefore, iostat shows metadata IO statistics only, which has been
confusing to users.

Add iostat support to the DAX read/write path.

Note, iostat still does not support the DAX mmap path as it allows user
applications to access directly.

[akpm@linux-foundation.org: make do_acct a bool]
Link: http://lkml.kernel.org/r/20170113233418.32252-1-toshi.kani@hpe.com
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/dax.c |   15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff -puN fs/dax.c~dax-enable-iostat-for-read-write fs/dax.c
--- a/fs/dax.c~dax-enable-iostat-for-read-write
+++ a/fs/dax.c
@@ -1081,12 +1081,24 @@ dax_iomap_rw(struct kiocb *iocb, struct
 {
 	struct address_space *mapping = iocb->ki_filp->f_mapping;
 	struct inode *inode = mapping->host;
+	struct gendisk *disk = inode->i_sb->s_bdev->bd_disk;
 	loff_t pos = iocb->ki_pos, ret = 0, done = 0;
 	unsigned flags = 0;
+	unsigned long start = 0;
+	bool do_acct = blk_queue_io_stat(disk->queue);
 
 	if (iov_iter_rw(iter) == WRITE)
 		flags |= IOMAP_WRITE;
 
+	if (do_acct) {
+		size_t sec = iov_iter_count(iter) >> 9;
+
+		start = jiffies;
+		generic_start_io_acct(iov_iter_rw(iter),
+				      max_t(unsigned long, 1, sec),
+				      &disk->part0);
+	}
+
 	while (iov_iter_count(iter)) {
 		ret = iomap_apply(inode, pos, iov_iter_count(iter), flags, ops,
 				iter, dax_iomap_actor);
@@ -1096,6 +1108,9 @@ dax_iomap_rw(struct kiocb *iocb, struct
 		done += ret;
 	}
 
+	if (do_acct)
+		generic_end_io_acct(iov_iter_rw(iter), &disk->part0, start);
+
 	iocb->ki_pos += done;
 	return done ? done : ret;
 }
_

Patches currently in -mm which might be from toshi.kani@hpe.com are