From 9a286f0e52a2dac362caf78a458efa8f3c05b99e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 21 Jun 2016 09:31:39 +1000 Subject: [PATCH] fs: support DAX based iomap zeroing This avoid needing a separate inefficient get_block based DAX zero_range implementation in file systems. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- fs/iomap.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/fs/iomap.c b/fs/iomap.c index 8e2fc17c266f..477817c00bac 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -24,6 +24,7 @@ #include #include #include +#include #include "internal.h" typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len, @@ -268,6 +269,15 @@ static int iomap_zero(struct inode *inode, loff_t pos, unsigned offset, return iomap_write_end(inode, pos, bytes, bytes, page); } +static int iomap_dax_zero(loff_t pos, unsigned offset, unsigned bytes, + struct iomap *iomap) +{ + sector_t sector = iomap->blkno + + (((pos & ~(PAGE_SIZE - 1)) - iomap->offset) >> 9); + + return __dax_zero_page_range(iomap->bdev, sector, offset, bytes); +} + static loff_t iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count, void *data, struct iomap *iomap) @@ -286,7 +296,10 @@ iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count, offset = pos & (PAGE_SIZE - 1); /* Within page */ bytes = min_t(unsigned, PAGE_SIZE - offset, count); - status = iomap_zero(inode, pos, offset, bytes, iomap); + if (IS_DAX(inode)) + status = iomap_dax_zero(pos, offset, bytes, iomap); + else + status = iomap_zero(inode, pos, offset, bytes, iomap); if (status < 0) return status; -- 2.20.1