[019/111] bio, fs: update RWA_MASK, READA and SWRITE to match the corresponding BIO_RW_* bits

[Greg KH]

2.6.32-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Tejun Heo <tj@xxxxxxxxxx>

commit aca27ba9618276dd2f777bcd5a1419589ccf1ca8 upstream.

Commit a82afdf (block: use the same failfast bits for bio and request)
moved BIO_RW_* bits around such that they match up with REQ_* bits.
Unfortunately, fs.h hard coded RW_MASK, RWA_MASK, READ, WRITE, READA
and SWRITE as 0, 1, 2 and 3, and expected them to match with BIO_RW_*
bits.  READ/WRITE didn't change but BIO_RW_AHEAD was moved to bit 4
instead of bit 1, breaking RWA_MASK, READA and SWRITE.

This patch updates RWA_MASK, READA and SWRITE such that they match the
BIO_RW_* bits again.  A follow up patch will update the definitions to
directly use BIO_RW_* bits so that this kind of breakage won't happen
again.

Neil also spotted missing RWA_MASK conversion.

Stable: The offending commit a82afdf was released with v2.6.32, so
this patch should be applied to all kernels since then but it must
_NOT_ be applied to kernels earlier than that.

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Reported-and-bisected-by: Vladislav Bolkhovitin <vst@xxxxxxxx>
Root-caused-by: Neil Brown <neilb@xxxxxxx>
Signed-off-by: Jens Axboe <jaxboe@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 include/linux/fs.h |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -145,11 +145,11 @@ struct inodes_stat_t {
  *
  */
 #define RW_MASK		1
-#define RWA_MASK	2
+#define RWA_MASK		16
 #define READ 0
 #define WRITE 1
-#define READA 2		/* read-ahead  - don't block if no resources */
-#define SWRITE 3	/* for ll_rw_block() - wait for buffer lock */
+#define READA			16 /* readahead - don't block if no resources */
+#define SWRITE			17 /* for ll_rw_block(), wait for buffer lock */
 #define READ_SYNC	(READ | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG))
 #define READ_META	(READ | (1 << BIO_RW_META))
 #define WRITE_SYNC_PLUG	(WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))


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