linux/fs/xfs/xfs_bio_io.c
Christoph Hellwig 488ca3d8d0 xfs: chain bios the right way around in xfs_rw_bdev
We need to chain the earlier bios to the later ones, so that
submit_bio_wait waits on the bio that all the completions are
dispatched to.

Fixes: 6ad5b3255b ("xfs: use bios directly to read and write the log recovery buffers")
Reported-by: Dave Chinner <david@fromorbit.com>
Tested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-07-10 10:04:16 -07:00

62 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2019 Christoph Hellwig.
*/
#include "xfs.h"
static inline unsigned int bio_max_vecs(unsigned int count)
{
return min_t(unsigned, howmany(count, PAGE_SIZE), BIO_MAX_PAGES);
}
int
xfs_rw_bdev(
struct block_device *bdev,
sector_t sector,
unsigned int count,
char *data,
unsigned int op)
{
unsigned int is_vmalloc = is_vmalloc_addr(data);
unsigned int left = count;
int error;
struct bio *bio;
if (is_vmalloc && op == REQ_OP_WRITE)
flush_kernel_vmap_range(data, count);
bio = bio_alloc(GFP_KERNEL, bio_max_vecs(left));
bio_set_dev(bio, bdev);
bio->bi_iter.bi_sector = sector;
bio->bi_opf = op | REQ_META | REQ_SYNC;
do {
struct page *page = kmem_to_page(data);
unsigned int off = offset_in_page(data);
unsigned int len = min_t(unsigned, left, PAGE_SIZE - off);
while (bio_add_page(bio, page, len, off) != len) {
struct bio *prev = bio;
bio = bio_alloc(GFP_KERNEL, bio_max_vecs(left));
bio_copy_dev(bio, prev);
bio->bi_iter.bi_sector = bio_end_sector(prev);
bio->bi_opf = prev->bi_opf;
bio_chain(prev, bio);
submit_bio(prev);
}
data += len;
left -= len;
} while (left > 0);
error = submit_bio_wait(bio);
bio_put(bio);
if (is_vmalloc && op == REQ_OP_READ)
invalidate_kernel_vmap_range(data, count);
return error;
}