vfs: guard end of device for mpage interface

Add guard_bio_eod() check for mpage code in order to allow us to do IO
even on the odd last sectors of a device, even if the block size is some
multiple of the physical sector size.

Using mpage_readpages() for block device requires this guard check.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Akinobu Mita 2014-10-09 15:26:55 -07:00 committed by Linus Torvalds
parent 59d43914ed
commit 4db96b71e3
3 changed files with 8 additions and 1 deletions

View File

@ -2966,7 +2966,7 @@ static void end_bio_bh_io_sync(struct bio *bio, int err)
* errors, this only handles the "we need to be able to
* do IO at the final sector" case.
*/
static void guard_bio_eod(int rw, struct bio *bio)
void guard_bio_eod(int rw, struct bio *bio)
{
sector_t maxsector;
struct bio_vec *bvec = &bio->bi_io_vec[bio->bi_vcnt - 1];

View File

@ -34,6 +34,11 @@ static inline int __sync_blockdev(struct block_device *bdev, int wait)
}
#endif
/*
* buffer.c
*/
extern void guard_bio_eod(int rw, struct bio *bio);
/*
* char_dev.c
*/

View File

@ -28,6 +28,7 @@
#include <linux/backing-dev.h>
#include <linux/pagevec.h>
#include <linux/cleancache.h>
#include "internal.h"
/*
* I/O completion handler for multipage BIOs.
@ -57,6 +58,7 @@ static void mpage_end_io(struct bio *bio, int err)
static struct bio *mpage_bio_submit(int rw, struct bio *bio)
{
bio->bi_end_io = mpage_end_io;
guard_bio_eod(rw, bio);
submit_bio(rw, bio);
return NULL;
}