Commit 29125ed6 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: move guard_bio_eod to bio.c 



This is bio layer functionality and not related to buffer heads.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 1b4d4dbd

block/bio.c

+43 −0
Original line number Diff line number Diff line
@@ -588,6 +588,49 @@ void bio_truncate(struct bio *bio, unsigned new_size) 
	bio->bi_iter.bi_size = new_size;

}



/**

 * guard_bio_eod - truncate a BIO to fit the block device

 * @bio:	bio to truncate

 *

 * This allows 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.

 *

 * We'll just truncate the bio to the size of the device, and clear the end of

 * the buffer head manually.  Truly out-of-range accesses will turn into actual

 * I/O errors, this only handles the "we need to be able to do I/O at the final

 * sector" case.

 */

void guard_bio_eod(struct bio *bio)

{

	sector_t maxsector;

	struct hd_struct *part;



	rcu_read_lock();

	part = __disk_get_part(bio->bi_disk, bio->bi_partno);

	if (part)

		maxsector = part_nr_sects_read(part);

	else

		maxsector = get_capacity(bio->bi_disk);

	rcu_read_unlock();



	if (!maxsector)

		return;



	/*

	 * If the *whole* IO is past the end of the device,

	 * let it through, and the IO layer will turn it into

	 * an EIO.

	 */

	if (unlikely(bio->bi_iter.bi_sector >= maxsector))

		return;



	maxsector -= bio->bi_iter.bi_sector;

	if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))

		return;



	bio_truncate(bio, maxsector << 9);

}



/**

 * bio_put - release a reference to a bio

 * @bio:   bio to release reference to

fs/buffer.c

+0 −43
Original line number Diff line number Diff line
@@ -3019,49 +3019,6 @@ static void end_bio_bh_io_sync(struct bio *bio) 
	bio_put(bio);

}



/*

 * This allows 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.

 *

 * We'll just truncate the bio to the size of the device,

 * and clear the end of the buffer head manually.

 *

 * Truly out-of-range accesses will turn into actual IO

 * errors, this only handles the "we need to be able to

 * do IO at the final sector" case.

 */

void guard_bio_eod(struct bio *bio)

{

	sector_t maxsector;

	struct hd_struct *part;



	rcu_read_lock();

	part = __disk_get_part(bio->bi_disk, bio->bi_partno);

	if (part)

		maxsector = part_nr_sects_read(part);

	else

		maxsector = get_capacity(bio->bi_disk);

	rcu_read_unlock();



	if (!maxsector)

		return;



	/*

	 * If the *whole* IO is past the end of the device,

	 * let it through, and the IO layer will turn it into

	 * an EIO.

	 */

	if (unlikely(bio->bi_iter.bi_sector >= maxsector))

		return;



	maxsector -= bio->bi_iter.bi_sector;

	if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))

		return;



	bio_truncate(bio, maxsector << 9);

}



static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,

			 enum rw_hint write_hint, struct writeback_control *wbc)

{

fs/internal.h

+0 −1
Original line number Diff line number Diff line
@@ -38,7 +38,6 @@ static inline int __sync_blockdev(struct block_device *bdev, int wait) 
/*

 * buffer.c

 */

extern void guard_bio_eod(struct bio *bio);

extern int __block_write_begin_int(struct page *page, loff_t pos, unsigned len,

		get_block_t *get_block, struct iomap *iomap);

include/linux/bio.h

+1 −0
Original line number Diff line number Diff line
@@ -471,6 +471,7 @@ extern struct bio *bio_copy_user_iov(struct request_queue *, 
extern int bio_uncopy_user(struct bio *);

void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);

void bio_truncate(struct bio *bio, unsigned new_size);

void guard_bio_eod(struct bio *bio);



static inline void zero_fill_bio(struct bio *bio)

{

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