From b32f4c7ed85c5cee2a21a55c9f59ebc9d57a2463 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Sat, 29 Sep 2012 17:15:37 -0700 Subject: target/file: Re-enable optional fd_buffered_io=1 operation This patch re-adds the ability to optionally run in buffered FILEIO mode (eg: w/o O_DSYNC) for device backends in order to once again use the Linux buffered cache as a write-back storage mechanism. This logic was originally dropped with mainline v3.5-rc commit: commit a4dff3043c231d57f982af635c9d2192ee40e5ae Author: Nicholas Bellinger Date: Wed May 30 16:25:41 2012 -0700 target/file: Use O_DSYNC by default for FILEIO backends This difference with this patch is that fd_create_virtdevice() now forces the explicit setting of emulate_write_cache=1 when buffered FILEIO operation has been enabled. (v2: Switch to FDBD_HAS_BUFFERED_IO_WCE + add more detailed comment as requested by hch) Reported-by: Ferry Cc: Christoph Hellwig Cc: Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_file.h | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/target/target_core_file.h') diff --git a/drivers/target/target_core_file.h b/drivers/target/target_core_file.h index 70ce7fd7111d..876ae53ef5b8 100644 --- a/drivers/target/target_core_file.h +++ b/drivers/target/target_core_file.h @@ -14,6 +14,7 @@ #define FBDF_HAS_PATH 0x01 #define FBDF_HAS_SIZE 0x02 +#define FDBD_HAS_BUFFERED_IO_WCE 0x04 struct fd_dev { u32 fbd_flags; -- cgit v1.2.3