1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * RDMA Network Block Driver
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
6*4882a593Smuzhiyun * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
7*4882a593Smuzhiyun * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun #undef pr_fmt
10*4882a593Smuzhiyun #define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #include "rnbd-srv-dev.h"
13*4882a593Smuzhiyun #include "rnbd-log.h"
14*4882a593Smuzhiyun
rnbd_dev_open(const char * path,fmode_t flags,struct bio_set * bs)15*4882a593Smuzhiyun struct rnbd_dev *rnbd_dev_open(const char *path, fmode_t flags,
16*4882a593Smuzhiyun struct bio_set *bs)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun struct rnbd_dev *dev;
19*4882a593Smuzhiyun int ret;
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun dev = kzalloc(sizeof(*dev), GFP_KERNEL);
22*4882a593Smuzhiyun if (!dev)
23*4882a593Smuzhiyun return ERR_PTR(-ENOMEM);
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun dev->blk_open_flags = flags;
26*4882a593Smuzhiyun dev->bdev = blkdev_get_by_path(path, flags, THIS_MODULE);
27*4882a593Smuzhiyun ret = PTR_ERR_OR_ZERO(dev->bdev);
28*4882a593Smuzhiyun if (ret)
29*4882a593Smuzhiyun goto err;
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun dev->blk_open_flags = flags;
32*4882a593Smuzhiyun bdevname(dev->bdev, dev->name);
33*4882a593Smuzhiyun dev->ibd_bio_set = bs;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun return dev;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun err:
38*4882a593Smuzhiyun kfree(dev);
39*4882a593Smuzhiyun return ERR_PTR(ret);
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
rnbd_dev_close(struct rnbd_dev * dev)42*4882a593Smuzhiyun void rnbd_dev_close(struct rnbd_dev *dev)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun blkdev_put(dev->bdev, dev->blk_open_flags);
45*4882a593Smuzhiyun kfree(dev);
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun
rnbd_dev_bi_end_io(struct bio * bio)48*4882a593Smuzhiyun void rnbd_dev_bi_end_io(struct bio *bio)
49*4882a593Smuzhiyun {
50*4882a593Smuzhiyun struct rnbd_dev_blk_io *io = bio->bi_private;
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun rnbd_endio(io->priv, blk_status_to_errno(bio->bi_status));
53*4882a593Smuzhiyun bio_put(bio);
54*4882a593Smuzhiyun }
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun /**
57*4882a593Smuzhiyun * rnbd_bio_map_kern - map kernel address into bio
58*4882a593Smuzhiyun * @data: pointer to buffer to map
59*4882a593Smuzhiyun * @bs: bio_set to use.
60*4882a593Smuzhiyun * @len: length in bytes
61*4882a593Smuzhiyun * @gfp_mask: allocation flags for bio allocation
62*4882a593Smuzhiyun *
63*4882a593Smuzhiyun * Map the kernel address into a bio suitable for io to a block
64*4882a593Smuzhiyun * device. Returns an error pointer in case of error.
65*4882a593Smuzhiyun */
rnbd_bio_map_kern(void * data,struct bio_set * bs,unsigned int len,gfp_t gfp_mask)66*4882a593Smuzhiyun struct bio *rnbd_bio_map_kern(void *data, struct bio_set *bs,
67*4882a593Smuzhiyun unsigned int len, gfp_t gfp_mask)
68*4882a593Smuzhiyun {
69*4882a593Smuzhiyun unsigned long kaddr = (unsigned long)data;
70*4882a593Smuzhiyun unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
71*4882a593Smuzhiyun unsigned long start = kaddr >> PAGE_SHIFT;
72*4882a593Smuzhiyun const int nr_pages = end - start;
73*4882a593Smuzhiyun int offset, i;
74*4882a593Smuzhiyun struct bio *bio;
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun bio = bio_alloc_bioset(gfp_mask, nr_pages, bs);
77*4882a593Smuzhiyun if (!bio)
78*4882a593Smuzhiyun return ERR_PTR(-ENOMEM);
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun offset = offset_in_page(kaddr);
81*4882a593Smuzhiyun for (i = 0; i < nr_pages; i++) {
82*4882a593Smuzhiyun unsigned int bytes = PAGE_SIZE - offset;
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun if (len <= 0)
85*4882a593Smuzhiyun break;
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun if (bytes > len)
88*4882a593Smuzhiyun bytes = len;
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun if (bio_add_page(bio, virt_to_page(data), bytes,
91*4882a593Smuzhiyun offset) < bytes) {
92*4882a593Smuzhiyun /* we don't support partial mappings */
93*4882a593Smuzhiyun bio_put(bio);
94*4882a593Smuzhiyun return ERR_PTR(-EINVAL);
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun data += bytes;
98*4882a593Smuzhiyun len -= bytes;
99*4882a593Smuzhiyun offset = 0;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun return bio;
103*4882a593Smuzhiyun }
104