Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2001-2003 Sistina Software (UK) Limited. |
| 3 | * |
| 4 | * This file is released under the GPL. |
| 5 | */ |
| 6 | |
| 7 | #include "dm.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | #include <linux/module.h> |
| 9 | #include <linux/init.h> |
| 10 | #include <linux/blkdev.h> |
| 11 | #include <linux/bio.h> |
Dan Williams | 817bf40 | 2017-04-12 13:37:44 -0700 | [diff] [blame] | 12 | #include <linux/dax.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/slab.h> |
Mikulas Patocka | 586e80e | 2008-10-21 17:44:59 +0100 | [diff] [blame] | 14 | #include <linux/device-mapper.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 16 | #define DM_MSG_PREFIX "linear" |
| 17 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | /* |
| 19 | * Linear: maps a linear range of a device. |
| 20 | */ |
| 21 | struct linear_c { |
| 22 | struct dm_dev *dev; |
| 23 | sector_t start; |
| 24 | }; |
| 25 | |
| 26 | /* |
| 27 | * Construct a linear mapping: <dev_path> <offset> |
| 28 | */ |
| 29 | static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
| 30 | { |
| 31 | struct linear_c *lc; |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 32 | unsigned long long tmp; |
Mikulas Patocka | 31998ef | 2012-03-28 18:41:26 +0100 | [diff] [blame] | 33 | char dummy; |
Vivek Goyal | e80d1c8 | 2015-07-31 09:20:36 -0400 | [diff] [blame] | 34 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
| 36 | if (argc != 2) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 37 | ti->error = "Invalid argument count"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | return -EINVAL; |
| 39 | } |
| 40 | |
| 41 | lc = kmalloc(sizeof(*lc), GFP_KERNEL); |
| 42 | if (lc == NULL) { |
Tomohiro Kusumi | 00272c8 | 2015-10-28 04:38:58 +0900 | [diff] [blame] | 43 | ti->error = "Cannot allocate linear context"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | return -ENOMEM; |
| 45 | } |
| 46 | |
Vivek Goyal | e80d1c8 | 2015-07-31 09:20:36 -0400 | [diff] [blame] | 47 | ret = -EINVAL; |
Mikulas Patocka | 31998ef | 2012-03-28 18:41:26 +0100 | [diff] [blame] | 48 | if (sscanf(argv[1], "%llu%c", &tmp, &dummy) != 1) { |
Tomohiro Kusumi | 00272c8 | 2015-10-28 04:38:58 +0900 | [diff] [blame] | 49 | ti->error = "Invalid device sector"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | goto bad; |
| 51 | } |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 52 | lc->start = tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | |
Vivek Goyal | e80d1c8 | 2015-07-31 09:20:36 -0400 | [diff] [blame] | 54 | ret = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &lc->dev); |
| 55 | if (ret) { |
Tomohiro Kusumi | 00272c8 | 2015-10-28 04:38:58 +0900 | [diff] [blame] | 56 | ti->error = "Device lookup failed"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | goto bad; |
| 58 | } |
| 59 | |
Alasdair G Kergon | 55a62ee | 2013-03-01 22:45:47 +0000 | [diff] [blame] | 60 | ti->num_flush_bios = 1; |
| 61 | ti->num_discard_bios = 1; |
| 62 | ti->num_write_same_bios = 1; |
Christoph Hellwig | ac62d62 | 2017-04-05 19:21:05 +0200 | [diff] [blame] | 63 | ti->num_write_zeroes_bios = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | ti->private = lc; |
| 65 | return 0; |
| 66 | |
| 67 | bad: |
| 68 | kfree(lc); |
Vivek Goyal | e80d1c8 | 2015-07-31 09:20:36 -0400 | [diff] [blame] | 69 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | } |
| 71 | |
| 72 | static void linear_dtr(struct dm_target *ti) |
| 73 | { |
| 74 | struct linear_c *lc = (struct linear_c *) ti->private; |
| 75 | |
| 76 | dm_put_device(ti, lc->dev); |
| 77 | kfree(lc); |
| 78 | } |
| 79 | |
Milan Broz | 7bc3447 | 2008-07-21 12:00:38 +0100 | [diff] [blame] | 80 | static sector_t linear_map_sector(struct dm_target *ti, sector_t bi_sector) |
| 81 | { |
| 82 | struct linear_c *lc = ti->private; |
| 83 | |
Alasdair G Kergon | b441a262 | 2010-08-12 04:14:11 +0100 | [diff] [blame] | 84 | return lc->start + dm_target_offset(ti, bi_sector); |
Milan Broz | 7bc3447 | 2008-07-21 12:00:38 +0100 | [diff] [blame] | 85 | } |
| 86 | |
| 87 | static void linear_map_bio(struct dm_target *ti, struct bio *bio) |
| 88 | { |
| 89 | struct linear_c *lc = ti->private; |
| 90 | |
Christoph Hellwig | 74d4699 | 2017-08-23 19:10:32 +0200 | [diff] [blame] | 91 | bio_set_dev(bio, lc->dev->bdev); |
Damien Le Moal | 0be12c1 | 2017-05-08 16:40:50 -0700 | [diff] [blame] | 92 | if (bio_sectors(bio) || bio_op(bio) == REQ_OP_ZONE_RESET) |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 93 | bio->bi_iter.bi_sector = |
| 94 | linear_map_sector(ti, bio->bi_iter.bi_sector); |
Milan Broz | 7bc3447 | 2008-07-21 12:00:38 +0100 | [diff] [blame] | 95 | } |
| 96 | |
Mikulas Patocka | 7de3ee5 | 2012-12-21 20:23:41 +0000 | [diff] [blame] | 97 | static int linear_map(struct dm_target *ti, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | { |
Milan Broz | 7bc3447 | 2008-07-21 12:00:38 +0100 | [diff] [blame] | 99 | linear_map_bio(ti, bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | |
Kiyoshi Ueda | d2a7ad2 | 2006-12-08 02:41:06 -0800 | [diff] [blame] | 101 | return DM_MAPIO_REMAPPED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | } |
| 103 | |
Damien Le Moal | c339fab | 2018-10-11 11:45:30 +0900 | [diff] [blame] | 104 | #ifdef CONFIG_BLK_DEV_ZONED |
Damien Le Moal | 0be12c1 | 2017-05-08 16:40:50 -0700 | [diff] [blame] | 105 | static int linear_end_io(struct dm_target *ti, struct bio *bio, |
| 106 | blk_status_t *error) |
| 107 | { |
| 108 | struct linear_c *lc = ti->private; |
| 109 | |
| 110 | if (!*error && bio_op(bio) == REQ_OP_ZONE_REPORT) |
| 111 | dm_remap_zone_report(ti, bio, lc->start); |
| 112 | |
| 113 | return DM_ENDIO_DONE; |
| 114 | } |
Mike Snitzer | efd6537 | 2018-10-10 12:01:55 -0400 | [diff] [blame] | 115 | #endif |
Damien Le Moal | 0be12c1 | 2017-05-08 16:40:50 -0700 | [diff] [blame] | 116 | |
Mikulas Patocka | fd7c092 | 2013-03-01 22:45:44 +0000 | [diff] [blame] | 117 | static void linear_status(struct dm_target *ti, status_type_t type, |
| 118 | unsigned status_flags, char *result, unsigned maxlen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
| 120 | struct linear_c *lc = (struct linear_c *) ti->private; |
| 121 | |
| 122 | switch (type) { |
| 123 | case STATUSTYPE_INFO: |
| 124 | result[0] = '\0'; |
| 125 | break; |
| 126 | |
| 127 | case STATUSTYPE_TABLE: |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 128 | snprintf(result, maxlen, "%s %llu", lc->dev->name, |
| 129 | (unsigned long long)lc->start); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | break; |
| 131 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | } |
| 133 | |
Christoph Hellwig | e56f81e | 2015-10-15 14:10:50 +0200 | [diff] [blame] | 134 | static int linear_prepare_ioctl(struct dm_target *ti, |
| 135 | struct block_device **bdev, fmode_t *mode) |
Milan Broz | ab17ffa | 2006-10-03 01:15:18 -0700 | [diff] [blame] | 136 | { |
| 137 | struct linear_c *lc = (struct linear_c *) ti->private; |
Paolo Bonzini | ec8013b | 2012-01-12 16:01:29 +0100 | [diff] [blame] | 138 | struct dm_dev *dev = lc->dev; |
Christoph Hellwig | e56f81e | 2015-10-15 14:10:50 +0200 | [diff] [blame] | 139 | |
| 140 | *bdev = dev->bdev; |
Paolo Bonzini | ec8013b | 2012-01-12 16:01:29 +0100 | [diff] [blame] | 141 | |
| 142 | /* |
| 143 | * Only pass ioctls through if the device sizes match exactly. |
| 144 | */ |
| 145 | if (lc->start || |
| 146 | ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT) |
Christoph Hellwig | e56f81e | 2015-10-15 14:10:50 +0200 | [diff] [blame] | 147 | return 1; |
| 148 | return 0; |
Milan Broz | ab17ffa | 2006-10-03 01:15:18 -0700 | [diff] [blame] | 149 | } |
| 150 | |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 151 | static int linear_iterate_devices(struct dm_target *ti, |
| 152 | iterate_devices_callout_fn fn, void *data) |
| 153 | { |
| 154 | struct linear_c *lc = ti->private; |
| 155 | |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 156 | return fn(ti, lc->dev, lc->start, ti->len, data); |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 157 | } |
| 158 | |
Dan Williams | 817bf40 | 2017-04-12 13:37:44 -0700 | [diff] [blame] | 159 | static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff, |
| 160 | long nr_pages, void **kaddr, pfn_t *pfn) |
Toshi Kani | 84b22f8 | 2016-06-22 17:54:54 -0600 | [diff] [blame] | 161 | { |
Dan Williams | 817bf40 | 2017-04-12 13:37:44 -0700 | [diff] [blame] | 162 | long ret; |
Toshi Kani | 84b22f8 | 2016-06-22 17:54:54 -0600 | [diff] [blame] | 163 | struct linear_c *lc = ti->private; |
| 164 | struct block_device *bdev = lc->dev->bdev; |
Dan Williams | 817bf40 | 2017-04-12 13:37:44 -0700 | [diff] [blame] | 165 | struct dax_device *dax_dev = lc->dev->dax_dev; |
| 166 | sector_t dev_sector, sector = pgoff * PAGE_SECTORS; |
Toshi Kani | 84b22f8 | 2016-06-22 17:54:54 -0600 | [diff] [blame] | 167 | |
Dan Williams | 817bf40 | 2017-04-12 13:37:44 -0700 | [diff] [blame] | 168 | dev_sector = linear_map_sector(ti, sector); |
| 169 | ret = bdev_dax_pgoff(bdev, dev_sector, nr_pages * PAGE_SIZE, &pgoff); |
| 170 | if (ret) |
| 171 | return ret; |
| 172 | return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn); |
Toshi Kani | 84b22f8 | 2016-06-22 17:54:54 -0600 | [diff] [blame] | 173 | } |
| 174 | |
Dan Williams | 7e026c8 | 2017-05-29 12:57:56 -0700 | [diff] [blame] | 175 | static size_t linear_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff, |
| 176 | void *addr, size_t bytes, struct iov_iter *i) |
| 177 | { |
| 178 | struct linear_c *lc = ti->private; |
| 179 | struct block_device *bdev = lc->dev->bdev; |
| 180 | struct dax_device *dax_dev = lc->dev->dax_dev; |
| 181 | sector_t dev_sector, sector = pgoff * PAGE_SECTORS; |
| 182 | |
| 183 | dev_sector = linear_map_sector(ti, sector); |
| 184 | if (bdev_dax_pgoff(bdev, dev_sector, ALIGN(bytes, PAGE_SIZE), &pgoff)) |
| 185 | return 0; |
| 186 | return dax_copy_from_iter(dax_dev, pgoff, addr, bytes, i); |
| 187 | } |
| 188 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | static struct target_type linear_target = { |
| 190 | .name = "linear", |
Damien Le Moal | 0be12c1 | 2017-05-08 16:40:50 -0700 | [diff] [blame] | 191 | .version = {1, 4, 0}, |
Damien Le Moal | c339fab | 2018-10-11 11:45:30 +0900 | [diff] [blame] | 192 | #ifdef CONFIG_BLK_DEV_ZONED |
Mike Snitzer | efd6537 | 2018-10-10 12:01:55 -0400 | [diff] [blame] | 193 | .end_io = linear_end_io, |
Damien Le Moal | 0be12c1 | 2017-05-08 16:40:50 -0700 | [diff] [blame] | 194 | .features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_ZONED_HM, |
Mike Snitzer | efd6537 | 2018-10-10 12:01:55 -0400 | [diff] [blame] | 195 | #else |
| 196 | .features = DM_TARGET_PASSES_INTEGRITY, |
| 197 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | .module = THIS_MODULE, |
| 199 | .ctr = linear_ctr, |
| 200 | .dtr = linear_dtr, |
| 201 | .map = linear_map, |
| 202 | .status = linear_status, |
Christoph Hellwig | e56f81e | 2015-10-15 14:10:50 +0200 | [diff] [blame] | 203 | .prepare_ioctl = linear_prepare_ioctl, |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 204 | .iterate_devices = linear_iterate_devices, |
Dan Williams | 817bf40 | 2017-04-12 13:37:44 -0700 | [diff] [blame] | 205 | .direct_access = linear_dax_direct_access, |
Dan Williams | 7e026c8 | 2017-05-29 12:57:56 -0700 | [diff] [blame] | 206 | .dax_copy_from_iter = linear_dax_copy_from_iter, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | }; |
| 208 | |
| 209 | int __init dm_linear_init(void) |
| 210 | { |
| 211 | int r = dm_register_target(&linear_target); |
| 212 | |
| 213 | if (r < 0) |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 214 | DMERR("register failed %d", r); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | |
| 216 | return r; |
| 217 | } |
| 218 | |
| 219 | void dm_linear_exit(void) |
| 220 | { |
Mikulas Patocka | 10d3bd0 | 2009-01-06 03:04:58 +0000 | [diff] [blame] | 221 | dm_unregister_target(&linear_target); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | } |