Commit | Line | Data |
---|---|---|
3bd94003 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * Copyright (C) 2001-2003 Sistina Software (UK) Limited. | |
4 | * | |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm.h" | |
1da177e4 LT |
9 | #include <linux/module.h> |
10 | #include <linux/init.h> | |
11 | #include <linux/blkdev.h> | |
12 | #include <linux/bio.h> | |
817bf402 | 13 | #include <linux/dax.h> |
1da177e4 | 14 | #include <linux/slab.h> |
586e80e6 | 15 | #include <linux/device-mapper.h> |
1da177e4 | 16 | |
72d94861 AK |
17 | #define DM_MSG_PREFIX "linear" |
18 | ||
1da177e4 LT |
19 | /* |
20 | * Linear: maps a linear range of a device. | |
21 | */ | |
22 | struct linear_c { | |
23 | struct dm_dev *dev; | |
24 | sector_t start; | |
25 | }; | |
26 | ||
27 | /* | |
28 | * Construct a linear mapping: <dev_path> <offset> | |
29 | */ | |
30 | static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
31 | { | |
32 | struct linear_c *lc; | |
4ee218cd | 33 | unsigned long long tmp; |
31998ef1 | 34 | char dummy; |
e80d1c80 | 35 | int ret; |
1da177e4 LT |
36 | |
37 | if (argc != 2) { | |
72d94861 | 38 | ti->error = "Invalid argument count"; |
1da177e4 LT |
39 | return -EINVAL; |
40 | } | |
41 | ||
42 | lc = kmalloc(sizeof(*lc), GFP_KERNEL); | |
43 | if (lc == NULL) { | |
00272c85 | 44 | ti->error = "Cannot allocate linear context"; |
1da177e4 LT |
45 | return -ENOMEM; |
46 | } | |
47 | ||
e80d1c80 | 48 | ret = -EINVAL; |
ef87bfc2 | 49 | if (sscanf(argv[1], "%llu%c", &tmp, &dummy) != 1 || tmp != (sector_t)tmp) { |
00272c85 | 50 | ti->error = "Invalid device sector"; |
1da177e4 LT |
51 | goto bad; |
52 | } | |
4ee218cd | 53 | lc->start = tmp; |
1da177e4 | 54 | |
e80d1c80 VG |
55 | ret = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &lc->dev); |
56 | if (ret) { | |
00272c85 | 57 | ti->error = "Device lookup failed"; |
1da177e4 LT |
58 | goto bad; |
59 | } | |
60 | ||
55a62eef AK |
61 | ti->num_flush_bios = 1; |
62 | ti->num_discard_bios = 1; | |
00716545 | 63 | ti->num_secure_erase_bios = 1; |
ac62d620 | 64 | ti->num_write_zeroes_bios = 1; |
1da177e4 LT |
65 | ti->private = lc; |
66 | return 0; | |
67 | ||
a6ba79c0 | 68 | bad: |
1da177e4 | 69 | kfree(lc); |
e80d1c80 | 70 | return ret; |
1da177e4 LT |
71 | } |
72 | ||
73 | static void linear_dtr(struct dm_target *ti) | |
74 | { | |
26cb62a2 | 75 | struct linear_c *lc = ti->private; |
1da177e4 LT |
76 | |
77 | dm_put_device(ti, lc->dev); | |
78 | kfree(lc); | |
79 | } | |
80 | ||
7bc3447b | 81 | static sector_t linear_map_sector(struct dm_target *ti, sector_t bi_sector) |
1da177e4 | 82 | { |
7bc3447b MB |
83 | struct linear_c *lc = ti->private; |
84 | ||
b441a262 | 85 | return lc->start + dm_target_offset(ti, bi_sector); |
7bc3447b MB |
86 | } |
87 | ||
e86f2b00 | 88 | static int linear_map(struct dm_target *ti, struct bio *bio) |
7bc3447b MB |
89 | { |
90 | struct linear_c *lc = ti->private; | |
1da177e4 | 91 | |
74d46992 | 92 | bio_set_dev(bio, lc->dev->bdev); |
e86f2b00 | 93 | bio->bi_iter.bi_sector = linear_map_sector(ti, bio->bi_iter.bi_sector); |
1da177e4 | 94 | |
d2a7ad29 | 95 | return DM_MAPIO_REMAPPED; |
1da177e4 LT |
96 | } |
97 | ||
fd7c092e | 98 | static void linear_status(struct dm_target *ti, status_type_t type, |
86a3238c | 99 | unsigned int status_flags, char *result, unsigned int maxlen) |
1da177e4 | 100 | { |
26cb62a2 | 101 | struct linear_c *lc = ti->private; |
8ec45662 | 102 | size_t sz = 0; |
1da177e4 LT |
103 | |
104 | switch (type) { | |
105 | case STATUSTYPE_INFO: | |
106 | result[0] = '\0'; | |
107 | break; | |
108 | ||
109 | case STATUSTYPE_TABLE: | |
8ec45662 TS |
110 | DMEMIT("%s %llu", lc->dev->name, (unsigned long long)lc->start); |
111 | break; | |
112 | ||
113 | case STATUSTYPE_IMA: | |
114 | DMEMIT_TARGET_NAME_VERSION(ti->type); | |
115 | DMEMIT(",device_name=%s,start=%llu;", lc->dev->name, | |
116 | (unsigned long long)lc->start); | |
1da177e4 LT |
117 | break; |
118 | } | |
1da177e4 LT |
119 | } |
120 | ||
5bd5e8d8 | 121 | static int linear_prepare_ioctl(struct dm_target *ti, struct block_device **bdev) |
ab17ffa4 | 122 | { |
26cb62a2 | 123 | struct linear_c *lc = ti->private; |
ec8013be | 124 | struct dm_dev *dev = lc->dev; |
e56f81e0 CH |
125 | |
126 | *bdev = dev->bdev; | |
ec8013be PB |
127 | |
128 | /* | |
129 | * Only pass ioctls through if the device sizes match exactly. | |
130 | */ | |
6dcbb52c | 131 | if (lc->start || ti->len != bdev_nr_sectors(dev->bdev)) |
e56f81e0 CH |
132 | return 1; |
133 | return 0; | |
ab17ffa4 MB |
134 | } |
135 | ||
e76239a3 | 136 | #ifdef CONFIG_BLK_DEV_ZONED |
d4100351 CH |
137 | static int linear_report_zones(struct dm_target *ti, |
138 | struct dm_report_zones_args *args, unsigned int nr_zones) | |
e76239a3 | 139 | { |
d4100351 | 140 | struct linear_c *lc = ti->private; |
e76239a3 | 141 | |
912e8875 DLM |
142 | return dm_report_zones(lc->dev->bdev, lc->start, |
143 | linear_map_sector(ti, args->next_sector), | |
144 | args, nr_zones); | |
e76239a3 | 145 | } |
e3290b94 MS |
146 | #else |
147 | #define linear_report_zones NULL | |
e76239a3 CH |
148 | #endif |
149 | ||
af4874e0 MS |
150 | static int linear_iterate_devices(struct dm_target *ti, |
151 | iterate_devices_callout_fn fn, void *data) | |
152 | { | |
153 | struct linear_c *lc = ti->private; | |
154 | ||
5dea271b | 155 | return fn(ti, lc->dev, lc->start, ti->len, data); |
af4874e0 MS |
156 | } |
157 | ||
5d2a228b | 158 | #if IS_ENABLED(CONFIG_FS_DAX) |
f43e0065 CH |
159 | static struct dax_device *linear_dax_pgoff(struct dm_target *ti, pgoff_t *pgoff) |
160 | { | |
161 | struct linear_c *lc = ti->private; | |
162 | sector_t sector = linear_map_sector(ti, *pgoff << PAGE_SECTORS_SHIFT); | |
163 | ||
164 | *pgoff = (get_start_sect(lc->dev->bdev) + sector) >> PAGE_SECTORS_SHIFT; | |
165 | return lc->dev->dax_dev; | |
166 | } | |
167 | ||
817bf402 | 168 | static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff, |
e511c4a3 JC |
169 | long nr_pages, enum dax_access_mode mode, void **kaddr, |
170 | pfn_t *pfn) | |
84b22f83 | 171 | { |
f43e0065 CH |
172 | struct dax_device *dax_dev = linear_dax_pgoff(ti, &pgoff); |
173 | ||
e511c4a3 | 174 | return dax_direct_access(dax_dev, pgoff, nr_pages, mode, kaddr, pfn); |
84b22f83 TK |
175 | } |
176 | ||
cdf6cdcd VG |
177 | static int linear_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff, |
178 | size_t nr_pages) | |
179 | { | |
f43e0065 CH |
180 | struct dax_device *dax_dev = linear_dax_pgoff(ti, &pgoff); |
181 | ||
cdf6cdcd VG |
182 | return dax_zero_page_range(dax_dev, pgoff, nr_pages); |
183 | } | |
184 | ||
047218ec JC |
185 | static size_t linear_dax_recovery_write(struct dm_target *ti, pgoff_t pgoff, |
186 | void *addr, size_t bytes, struct iov_iter *i) | |
187 | { | |
188 | struct dax_device *dax_dev = linear_dax_pgoff(ti, &pgoff); | |
189 | ||
190 | return dax_recovery_write(dax_dev, pgoff, addr, bytes, i); | |
191 | } | |
192 | ||
976431b0 DW |
193 | #else |
194 | #define linear_dax_direct_access NULL | |
cdf6cdcd | 195 | #define linear_dax_zero_page_range NULL |
047218ec | 196 | #define linear_dax_recovery_write NULL |
976431b0 DW |
197 | #endif |
198 | ||
1da177e4 LT |
199 | static struct target_type linear_target = { |
200 | .name = "linear", | |
0be12c1c | 201 | .version = {1, 4, 0}, |
6abc4946 | 202 | .features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_NOWAIT | |
3db564b4 | 203 | DM_TARGET_ZONED_HM | DM_TARGET_PASSES_CRYPTO, |
e76239a3 | 204 | .report_zones = linear_report_zones, |
1da177e4 LT |
205 | .module = THIS_MODULE, |
206 | .ctr = linear_ctr, | |
207 | .dtr = linear_dtr, | |
208 | .map = linear_map, | |
209 | .status = linear_status, | |
e56f81e0 | 210 | .prepare_ioctl = linear_prepare_ioctl, |
af4874e0 | 211 | .iterate_devices = linear_iterate_devices, |
817bf402 | 212 | .direct_access = linear_dax_direct_access, |
cdf6cdcd | 213 | .dax_zero_page_range = linear_dax_zero_page_range, |
047218ec | 214 | .dax_recovery_write = linear_dax_recovery_write, |
1da177e4 LT |
215 | }; |
216 | ||
217 | int __init dm_linear_init(void) | |
218 | { | |
219 | int r = dm_register_target(&linear_target); | |
220 | ||
221 | if (r < 0) | |
72d94861 | 222 | DMERR("register failed %d", r); |
1da177e4 LT |
223 | |
224 | return r; | |
225 | } | |
226 | ||
227 | void dm_linear_exit(void) | |
228 | { | |
10d3bd09 | 229 | dm_unregister_target(&linear_target); |
1da177e4 | 230 | } |