Avoid using BLKFLSBUF.

Now that we use O_DIRECT for all device IO, BLKFLSBUF is not needed to
ensure we get current data, and it can impose a cost if any flush-out
is needed.  So remove it.

To be safe, add O_DIRECT to one place where it isn't currently used:
when reading a bitmap.

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 0 insertions, 3 deletions

diff --git a/super1.c b/super1.c
index 3236a7e2..fe83af5b 100644
--- a/super1.c
+++ b/super1.c
@@ -1633,9 +1633,6 @@ static int load_super1(struct supertype *st, int fd, char *devname)
 		return -EINVAL;
 	}
 
-	ioctl(fd, BLKFLSBUF, 0); /* make sure we read current data */
-
-
 	if (lseek64(fd, sb_offset << 9, 0)< 0LL) {
 		if (devname)
 			pr_err("Cannot seek to superblock on %s: %s\n",