OpenCloudOS-Kernel/drivers/block/rnbd/rnbd-srv-dev.c

135 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* RDMA Network Block Driver
*
* Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
* Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
* Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
*/
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
#include "rnbd-srv-dev.h"
#include "rnbd-log.h"
struct rnbd_dev *rnbd_dev_open(const char *path, fmode_t flags,
struct bio_set *bs)
{
struct rnbd_dev *dev;
int ret;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
dev->blk_open_flags = flags;
dev->bdev = blkdev_get_by_path(path, flags, THIS_MODULE);
ret = PTR_ERR_OR_ZERO(dev->bdev);
if (ret)
goto err;
dev->blk_open_flags = flags;
bdevname(dev->bdev, dev->name);
dev->ibd_bio_set = bs;
return dev;
err:
kfree(dev);
return ERR_PTR(ret);
}
void rnbd_dev_close(struct rnbd_dev *dev)
{
blkdev_put(dev->bdev, dev->blk_open_flags);
kfree(dev);
}
static void rnbd_dev_bi_end_io(struct bio *bio)
{
struct rnbd_dev_blk_io *io = bio->bi_private;
rnbd_endio(io->priv, blk_status_to_errno(bio->bi_status));
bio_put(bio);
}
/**
* rnbd_bio_map_kern - map kernel address into bio
* @data: pointer to buffer to map
* @bs: bio_set to use.
* @len: length in bytes
* @gfp_mask: allocation flags for bio allocation
*
* Map the kernel address into a bio suitable for io to a block
* device. Returns an error pointer in case of error.
*/
static struct bio *rnbd_bio_map_kern(void *data, struct bio_set *bs,
unsigned int len, gfp_t gfp_mask)
{
unsigned long kaddr = (unsigned long)data;
unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
unsigned long start = kaddr >> PAGE_SHIFT;
const int nr_pages = end - start;
int offset, i;
struct bio *bio;
bio = bio_alloc_bioset(gfp_mask, nr_pages, bs);
if (!bio)
return ERR_PTR(-ENOMEM);
offset = offset_in_page(kaddr);
for (i = 0; i < nr_pages; i++) {
unsigned int bytes = PAGE_SIZE - offset;
if (len <= 0)
break;
if (bytes > len)
bytes = len;
if (bio_add_page(bio, virt_to_page(data), bytes,
offset) < bytes) {
/* we don't support partial mappings */
bio_put(bio);
return ERR_PTR(-EINVAL);
}
data += bytes;
len -= bytes;
offset = 0;
}
bio->bi_end_io = bio_put;
return bio;
}
int rnbd_dev_submit_io(struct rnbd_dev *dev, sector_t sector, void *data,
size_t len, u32 bi_size, enum rnbd_io_flags flags,
short prio, void *priv)
{
struct rnbd_dev_blk_io *io;
struct bio *bio;
/* Generate bio with pages pointing to the rdma buffer */
bio = rnbd_bio_map_kern(data, dev->ibd_bio_set, len, GFP_KERNEL);
if (IS_ERR(bio))
return PTR_ERR(bio);
io = container_of(bio, struct rnbd_dev_blk_io, bio);
io->dev = dev;
io->priv = priv;
bio->bi_end_io = rnbd_dev_bi_end_io;
bio->bi_private = io;
bio->bi_opf = rnbd_to_bio_flags(flags);
bio->bi_iter.bi_sector = sector;
bio->bi_iter.bi_size = bi_size;
bio_set_prio(bio, prio);
bio_set_dev(bio, dev->bdev);
submit_bio(bio);
return 0;
}