Commit | Line | Data |
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f31e7e40 DM |
1 | /* |
2 | * Functions related to generic helpers functions | |
3 | */ | |
4 | #include <linux/kernel.h> | |
5 | #include <linux/module.h> | |
6 | #include <linux/bio.h> | |
7 | #include <linux/blkdev.h> | |
8 | #include <linux/scatterlist.h> | |
9 | ||
10 | #include "blk.h" | |
11 | ||
5dba3089 LC |
12 | struct bio_batch { |
13 | atomic_t done; | |
14 | unsigned long flags; | |
15 | struct completion *wait; | |
16 | }; | |
17 | ||
18 | static void bio_batch_end_io(struct bio *bio, int err) | |
f31e7e40 | 19 | { |
5dba3089 LC |
20 | struct bio_batch *bb = bio->bi_private; |
21 | ||
8af1954d | 22 | if (err && (err != -EOPNOTSUPP)) |
5dba3089 | 23 | clear_bit(BIO_UPTODATE, &bb->flags); |
5dba3089 LC |
24 | if (atomic_dec_and_test(&bb->done)) |
25 | complete(bb->wait); | |
f31e7e40 DM |
26 | bio_put(bio); |
27 | } | |
28 | ||
29 | /** | |
30 | * blkdev_issue_discard - queue a discard | |
31 | * @bdev: blockdev to issue discard for | |
32 | * @sector: start sector | |
33 | * @nr_sects: number of sectors to discard | |
34 | * @gfp_mask: memory allocation flags (for bio_alloc) | |
35 | * @flags: BLKDEV_IFL_* flags to control behaviour | |
36 | * | |
37 | * Description: | |
38 | * Issue a discard request for the sectors in question. | |
39 | */ | |
40 | int blkdev_issue_discard(struct block_device *bdev, sector_t sector, | |
41 | sector_t nr_sects, gfp_t gfp_mask, unsigned long flags) | |
42 | { | |
43 | DECLARE_COMPLETION_ONSTACK(wait); | |
44 | struct request_queue *q = bdev_get_queue(bdev); | |
8c555367 | 45 | int type = REQ_WRITE | REQ_DISCARD; |
10d1f9e2 | 46 | unsigned int max_discard_sectors; |
c6e66634 | 47 | unsigned int granularity, alignment, mask; |
5dba3089 | 48 | struct bio_batch bb; |
f31e7e40 | 49 | struct bio *bio; |
f31e7e40 DM |
50 | int ret = 0; |
51 | ||
52 | if (!q) | |
53 | return -ENXIO; | |
54 | ||
55 | if (!blk_queue_discard(q)) | |
56 | return -EOPNOTSUPP; | |
57 | ||
f6ff53d3 PB |
58 | /* Zero-sector (unknown) and one-sector granularities are the same. */ |
59 | granularity = max(q->limits.discard_granularity >> 9, 1U); | |
c6e66634 PB |
60 | mask = granularity - 1; |
61 | alignment = (bdev_discard_alignment(bdev) >> 9) & mask; | |
f6ff53d3 | 62 | |
10d1f9e2 JA |
63 | /* |
64 | * Ensure that max_discard_sectors is of the proper | |
c6e66634 | 65 | * granularity, so that requests stay aligned after a split. |
10d1f9e2 JA |
66 | */ |
67 | max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9); | |
f6ff53d3 | 68 | max_discard_sectors = round_down(max_discard_sectors, granularity); |
4c64500e | 69 | if (unlikely(!max_discard_sectors)) { |
0f799603 MS |
70 | /* Avoid infinite loop below. Being cautious never hurts. */ |
71 | return -EOPNOTSUPP; | |
10d1f9e2 | 72 | } |
f31e7e40 | 73 | |
dd3932ed | 74 | if (flags & BLKDEV_DISCARD_SECURE) { |
8d57a98c AH |
75 | if (!blk_queue_secdiscard(q)) |
76 | return -EOPNOTSUPP; | |
8c555367 | 77 | type |= REQ_SECURE; |
8d57a98c AH |
78 | } |
79 | ||
5dba3089 LC |
80 | atomic_set(&bb.done, 1); |
81 | bb.flags = 1 << BIO_UPTODATE; | |
82 | bb.wait = &wait; | |
83 | ||
84 | while (nr_sects) { | |
c6e66634 PB |
85 | unsigned int req_sects; |
86 | sector_t end_sect; | |
87 | ||
f31e7e40 | 88 | bio = bio_alloc(gfp_mask, 1); |
66ac0280 CH |
89 | if (!bio) { |
90 | ret = -ENOMEM; | |
91 | break; | |
92 | } | |
93 | ||
c6e66634 PB |
94 | req_sects = min_t(sector_t, nr_sects, max_discard_sectors); |
95 | ||
96 | /* | |
97 | * If splitting a request, and the next starting sector would be | |
98 | * misaligned, stop the discard at the previous aligned sector. | |
99 | */ | |
100 | end_sect = sector + req_sects; | |
101 | if (req_sects < nr_sects && (end_sect & mask) != alignment) { | |
102 | end_sect = | |
103 | round_down(end_sect - alignment, granularity) | |
104 | + alignment; | |
105 | req_sects = end_sect - sector; | |
106 | } | |
107 | ||
f31e7e40 | 108 | bio->bi_sector = sector; |
5dba3089 | 109 | bio->bi_end_io = bio_batch_end_io; |
f31e7e40 | 110 | bio->bi_bdev = bdev; |
5dba3089 | 111 | bio->bi_private = &bb; |
f31e7e40 | 112 | |
c6e66634 PB |
113 | bio->bi_size = req_sects << 9; |
114 | nr_sects -= req_sects; | |
115 | sector = end_sect; | |
f31e7e40 | 116 | |
5dba3089 | 117 | atomic_inc(&bb.done); |
f31e7e40 | 118 | submit_bio(type, bio); |
5dba3089 | 119 | } |
f31e7e40 | 120 | |
5dba3089 LC |
121 | /* Wait for bios in-flight */ |
122 | if (!atomic_dec_and_test(&bb.done)) | |
dd3932ed | 123 | wait_for_completion(&wait); |
f31e7e40 | 124 | |
8af1954d | 125 | if (!test_bit(BIO_UPTODATE, &bb.flags)) |
5dba3089 | 126 | ret = -EIO; |
66ac0280 | 127 | |
f31e7e40 | 128 | return ret; |
f31e7e40 DM |
129 | } |
130 | EXPORT_SYMBOL(blkdev_issue_discard); | |
3f14d792 | 131 | |
3f14d792 | 132 | /** |
291d24f6 | 133 | * blkdev_issue_zeroout - generate number of zero filed write bios |
3f14d792 DM |
134 | * @bdev: blockdev to issue |
135 | * @sector: start sector | |
136 | * @nr_sects: number of sectors to write | |
137 | * @gfp_mask: memory allocation flags (for bio_alloc) | |
3f14d792 DM |
138 | * |
139 | * Description: | |
140 | * Generate and issue number of bios with zerofiled pages. | |
3f14d792 DM |
141 | */ |
142 | ||
143 | int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, | |
dd3932ed | 144 | sector_t nr_sects, gfp_t gfp_mask) |
3f14d792 | 145 | { |
18edc8ea | 146 | int ret; |
3f14d792 DM |
147 | struct bio *bio; |
148 | struct bio_batch bb; | |
0aeea189 | 149 | unsigned int sz; |
3f14d792 DM |
150 | DECLARE_COMPLETION_ONSTACK(wait); |
151 | ||
0aeea189 | 152 | atomic_set(&bb.done, 1); |
3f14d792 DM |
153 | bb.flags = 1 << BIO_UPTODATE; |
154 | bb.wait = &wait; | |
3f14d792 | 155 | |
18edc8ea | 156 | ret = 0; |
3f14d792 DM |
157 | while (nr_sects != 0) { |
158 | bio = bio_alloc(gfp_mask, | |
159 | min(nr_sects, (sector_t)BIO_MAX_PAGES)); | |
18edc8ea DM |
160 | if (!bio) { |
161 | ret = -ENOMEM; | |
3f14d792 | 162 | break; |
18edc8ea | 163 | } |
3f14d792 DM |
164 | |
165 | bio->bi_sector = sector; | |
166 | bio->bi_bdev = bdev; | |
167 | bio->bi_end_io = bio_batch_end_io; | |
dd3932ed | 168 | bio->bi_private = &bb; |
3f14d792 | 169 | |
0341aafb JA |
170 | while (nr_sects != 0) { |
171 | sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects); | |
3f14d792 DM |
172 | ret = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0); |
173 | nr_sects -= ret >> 9; | |
174 | sector += ret >> 9; | |
175 | if (ret < (sz << 9)) | |
176 | break; | |
177 | } | |
18edc8ea | 178 | ret = 0; |
0aeea189 | 179 | atomic_inc(&bb.done); |
3f14d792 DM |
180 | submit_bio(WRITE, bio); |
181 | } | |
3f14d792 | 182 | |
dd3932ed | 183 | /* Wait for bios in-flight */ |
0aeea189 | 184 | if (!atomic_dec_and_test(&bb.done)) |
dd3932ed | 185 | wait_for_completion(&wait); |
3f14d792 DM |
186 | |
187 | if (!test_bit(BIO_UPTODATE, &bb.flags)) | |
188 | /* One of bios in the batch was completed with error.*/ | |
189 | ret = -EIO; | |
190 | ||
3f14d792 DM |
191 | return ret; |
192 | } | |
193 | EXPORT_SYMBOL(blkdev_issue_zeroout); |