97 lines
2.2 KiB
C
97 lines
2.2 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 bio_max_segs(howmany(count, PAGE_SIZE));
|
|
}
|
|
|
|
static void
|
|
xfs_flush_bdev_async_endio(
|
|
struct bio *bio)
|
|
{
|
|
complete(bio->bi_private);
|
|
}
|
|
|
|
/*
|
|
* Submit a request for an async cache flush to run. If the request queue does
|
|
* not require flush operations, just skip it altogether. If the caller needs
|
|
* to wait for the flush completion at a later point in time, they must supply a
|
|
* valid completion. This will be signalled when the flush completes. The
|
|
* caller never sees the bio that is issued here.
|
|
*/
|
|
void
|
|
xfs_flush_bdev_async(
|
|
struct bio *bio,
|
|
struct block_device *bdev,
|
|
struct completion *done)
|
|
{
|
|
struct request_queue *q = bdev->bd_disk->queue;
|
|
|
|
if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
|
|
complete(done);
|
|
return;
|
|
}
|
|
|
|
bio_init(bio, NULL, 0);
|
|
bio_set_dev(bio, bdev);
|
|
bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC;
|
|
bio->bi_private = done;
|
|
bio->bi_end_io = xfs_flush_bdev_async_endio;
|
|
|
|
submit_bio(bio);
|
|
}
|
|
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;
|
|
}
|