From bbab37ddc20bae4709bca8745c128c4f46fe63c5 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 3 Jul 2015 10:40:42 -0400 Subject: block: Add support for DAX reads/writes to block devices If a block device supports the ->direct_access methods, bypass the normal DIO path and use DAX to go straight to memcpy() instead of allocating a DIO and a BIO. Includes support for the DIO_SKIP_DIO_COUNT flag in DAX, as is done in do_blockdev_direct_IO(). Signed-off-by: Matthew Wilcox Signed-off-by: Al Viro --- fs/dax.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'fs/dax.c') diff --git a/fs/dax.c b/fs/dax.c index 159f796afa85..37a0c4826c1a 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -209,7 +209,8 @@ ssize_t dax_do_io(struct kiocb *iocb, struct inode *inode, } /* Protects against truncate */ - inode_dio_begin(inode); + if (!(flags & DIO_SKIP_DIO_COUNT)) + inode_dio_begin(inode); retval = dax_io(inode, iter, pos, end, get_block, &bh); @@ -219,7 +220,8 @@ ssize_t dax_do_io(struct kiocb *iocb, struct inode *inode, if ((retval > 0) && end_io) end_io(iocb, pos, retval, bh.b_private); - inode_dio_end(inode); + if (!(flags & DIO_SKIP_DIO_COUNT)) + inode_dio_end(inode); out: return retval; } -- cgit v1.2.3