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4#include <linux/kernel.h>
5#include <linux/module.h>
6#include <linux/bio.h>
7#include <linux/blkdev.h>
8#include <linux/uio.h>
9
10#include "blk.h"
11
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14
15
16int blk_rq_append_bio(struct request *rq, struct bio *bio)
17{
18 if (!rq->bio) {
19 blk_rq_bio_prep(rq->q, rq, bio);
20 } else {
21 if (!ll_back_merge_fn(rq->q, rq, bio))
22 return -EINVAL;
23
24 rq->biotail->bi_next = bio;
25 rq->biotail = bio;
26 rq->__data_len += bio->bi_iter.bi_size;
27 }
28
29 return 0;
30}
31EXPORT_SYMBOL(blk_rq_append_bio);
32
33static int __blk_rq_unmap_user(struct bio *bio)
34{
35 int ret = 0;
36
37 if (bio) {
38 if (bio_flagged(bio, BIO_USER_MAPPED))
39 bio_unmap_user(bio);
40 else
41 ret = bio_uncopy_user(bio);
42 }
43
44 return ret;
45}
46
47static int __blk_rq_map_user_iov(struct request *rq,
48 struct rq_map_data *map_data, struct iov_iter *iter,
49 gfp_t gfp_mask, bool copy)
50{
51 struct request_queue *q = rq->q;
52 struct bio *bio, *orig_bio;
53 int ret;
54
55 if (copy)
56 bio = bio_copy_user_iov(q, map_data, iter, gfp_mask);
57 else
58 bio = bio_map_user_iov(q, iter, gfp_mask);
59
60 if (IS_ERR(bio))
61 return PTR_ERR(bio);
62
63 if (map_data && map_data->null_mapped)
64 bio_set_flag(bio, BIO_NULL_MAPPED);
65
66 iov_iter_advance(iter, bio->bi_iter.bi_size);
67 if (map_data)
68 map_data->offset += bio->bi_iter.bi_size;
69
70 orig_bio = bio;
71 blk_queue_bounce(q, &bio);
72
73
74
75
76
77 bio_get(bio);
78
79 ret = blk_rq_append_bio(rq, bio);
80 if (ret) {
81 bio_endio(bio);
82 __blk_rq_unmap_user(orig_bio);
83 bio_put(bio);
84 return ret;
85 }
86
87 return 0;
88}
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111int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
112 struct rq_map_data *map_data,
113 const struct iov_iter *iter, gfp_t gfp_mask)
114{
115 bool copy = false;
116 unsigned long align = q->dma_pad_mask | queue_dma_alignment(q);
117 struct bio *bio = NULL;
118 struct iov_iter i;
119 int ret;
120
121 if (!iter_is_iovec(iter))
122 goto fail;
123
124 if (map_data)
125 copy = true;
126 else if (iov_iter_alignment(iter) & align)
127 copy = true;
128 else if (queue_virt_boundary(q))
129 copy = queue_virt_boundary(q) & iov_iter_gap_alignment(iter);
130
131 i = *iter;
132 do {
133 ret =__blk_rq_map_user_iov(rq, map_data, &i, gfp_mask, copy);
134 if (ret)
135 goto unmap_rq;
136 if (!bio)
137 bio = rq->bio;
138 } while (iov_iter_count(&i));
139
140 if (!bio_flagged(bio, BIO_USER_MAPPED))
141 rq->cmd_flags |= REQ_COPY_USER;
142 return 0;
143
144unmap_rq:
145 __blk_rq_unmap_user(bio);
146fail:
147 rq->bio = NULL;
148 return -EINVAL;
149}
150EXPORT_SYMBOL(blk_rq_map_user_iov);
151
152int blk_rq_map_user(struct request_queue *q, struct request *rq,
153 struct rq_map_data *map_data, void __user *ubuf,
154 unsigned long len, gfp_t gfp_mask)
155{
156 struct iovec iov;
157 struct iov_iter i;
158 int ret = import_single_range(rq_data_dir(rq), ubuf, len, &iov, &i);
159
160 if (unlikely(ret < 0))
161 return ret;
162
163 return blk_rq_map_user_iov(q, rq, map_data, &i, gfp_mask);
164}
165EXPORT_SYMBOL(blk_rq_map_user);
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175
176int blk_rq_unmap_user(struct bio *bio)
177{
178 struct bio *mapped_bio;
179 int ret = 0, ret2;
180
181 while (bio) {
182 mapped_bio = bio;
183 if (unlikely(bio_flagged(bio, BIO_BOUNCED)))
184 mapped_bio = bio->bi_private;
185
186 ret2 = __blk_rq_unmap_user(mapped_bio);
187 if (ret2 && !ret)
188 ret = ret2;
189
190 mapped_bio = bio;
191 bio = bio->bi_next;
192 bio_put(mapped_bio);
193 }
194
195 return ret;
196}
197EXPORT_SYMBOL(blk_rq_unmap_user);
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211
212int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
213 unsigned int len, gfp_t gfp_mask)
214{
215 int reading = rq_data_dir(rq) == READ;
216 unsigned long addr = (unsigned long) kbuf;
217 int do_copy = 0;
218 struct bio *bio;
219 int ret;
220
221 if (len > (queue_max_hw_sectors(q) << 9))
222 return -EINVAL;
223 if (!len || !kbuf)
224 return -EINVAL;
225
226 do_copy = !blk_rq_aligned(q, addr, len) || object_is_on_stack(kbuf);
227 if (do_copy)
228 bio = bio_copy_kern(q, kbuf, len, gfp_mask, reading);
229 else
230 bio = bio_map_kern(q, kbuf, len, gfp_mask);
231
232 if (IS_ERR(bio))
233 return PTR_ERR(bio);
234
235 if (!reading)
236 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
237
238 if (do_copy)
239 rq->cmd_flags |= REQ_COPY_USER;
240
241 ret = blk_rq_append_bio(rq, bio);
242 if (unlikely(ret)) {
243
244 bio_put(bio);
245 return ret;
246 }
247
248 blk_queue_bounce(q, &rq->bio);
249 return 0;
250}
251EXPORT_SYMBOL(blk_rq_map_kern);
252