Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1 | /* |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 2 | * Compressed RAM block device |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 3 | * |
Nitin Gupta | 1130ebb | 2010-01-28 21:21:35 +0530 | [diff] [blame] | 4 | * Copyright (C) 2008, 2009, 2010 Nitin Gupta |
Minchan Kim | 7bfb3de | 2014-01-30 15:45:55 -0800 | [diff] [blame] | 5 | * 2012, 2013 Minchan Kim |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 6 | * |
| 7 | * This code is released using a dual license strategy: BSD/GPL |
| 8 | * You can choose the licence that better fits your requirements. |
| 9 | * |
| 10 | * Released under the terms of 3-clause BSD License |
| 11 | * Released under the terms of GNU General Public License Version 2.0 |
| 12 | * |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 13 | */ |
| 14 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 15 | #define KMSG_COMPONENT "zram" |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 16 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
| 17 | |
Robert Jennings | b1f5b81 | 2011-01-28 08:59:26 -0600 | [diff] [blame] | 18 | #ifdef CONFIG_ZRAM_DEBUG |
| 19 | #define DEBUG |
| 20 | #endif |
| 21 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 22 | #include <linux/module.h> |
| 23 | #include <linux/kernel.h> |
Randy Dunlap | 8946a08 | 2010-06-23 20:27:09 -0700 | [diff] [blame] | 24 | #include <linux/bio.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 25 | #include <linux/bitops.h> |
| 26 | #include <linux/blkdev.h> |
| 27 | #include <linux/buffer_head.h> |
| 28 | #include <linux/device.h> |
| 29 | #include <linux/genhd.h> |
| 30 | #include <linux/highmem.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 31 | #include <linux/slab.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 32 | #include <linux/string.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 33 | #include <linux/vmalloc.h> |
Sergey Senozhatsky | fcfa8d9 | 2014-04-07 15:38:20 -0700 | [diff] [blame] | 34 | #include <linux/err.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 35 | |
Nitin Gupta | 16a4bfb | 2010-06-01 13:31:24 +0530 | [diff] [blame] | 36 | #include "zram_drv.h" |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 37 | |
| 38 | /* Globals */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 39 | static int zram_major; |
Jiang Liu | 0f0e3ba | 2013-06-07 00:07:29 +0800 | [diff] [blame] | 40 | static struct zram *zram_devices; |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 41 | static const char *default_compressor = "lzo"; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 42 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 43 | /* Module params (documentation at end) */ |
Davidlohr Bueso | ca3d70b | 2013-01-01 21:24:13 -0800 | [diff] [blame] | 44 | static unsigned int num_devices = 1; |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 45 | |
Sergey Senozhatsky | a68eb3b | 2014-04-07 15:38:04 -0700 | [diff] [blame] | 46 | #define ZRAM_ATTR_RO(name) \ |
| 47 | static ssize_t zram_attr_##name##_show(struct device *d, \ |
| 48 | struct device_attribute *attr, char *b) \ |
| 49 | { \ |
| 50 | struct zram *zram = dev_to_zram(d); \ |
Sergey Senozhatsky | 56b4e8c | 2014-04-07 15:38:22 -0700 | [diff] [blame] | 51 | return scnprintf(b, PAGE_SIZE, "%llu\n", \ |
Sergey Senozhatsky | a68eb3b | 2014-04-07 15:38:04 -0700 | [diff] [blame] | 52 | (u64)atomic64_read(&zram->stats.name)); \ |
| 53 | } \ |
| 54 | static struct device_attribute dev_attr_##name = \ |
| 55 | __ATTR(name, S_IRUGO, zram_attr_##name##_show, NULL); |
| 56 | |
Sergey Senozhatsky | be2d1d5 | 2014-04-07 15:38:00 -0700 | [diff] [blame] | 57 | static inline int init_done(struct zram *zram) |
| 58 | { |
| 59 | return zram->meta != NULL; |
| 60 | } |
| 61 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 62 | static inline struct zram *dev_to_zram(struct device *dev) |
| 63 | { |
| 64 | return (struct zram *)dev_to_disk(dev)->private_data; |
| 65 | } |
| 66 | |
| 67 | static ssize_t disksize_show(struct device *dev, |
| 68 | struct device_attribute *attr, char *buf) |
| 69 | { |
| 70 | struct zram *zram = dev_to_zram(dev); |
| 71 | |
Sergey Senozhatsky | 56b4e8c | 2014-04-07 15:38:22 -0700 | [diff] [blame] | 72 | return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 73 | } |
| 74 | |
| 75 | static ssize_t initstate_show(struct device *dev, |
| 76 | struct device_attribute *attr, char *buf) |
| 77 | { |
Sergey Senozhatsky | a68eb3b | 2014-04-07 15:38:04 -0700 | [diff] [blame] | 78 | u32 val; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 79 | struct zram *zram = dev_to_zram(dev); |
| 80 | |
Sergey Senozhatsky | a68eb3b | 2014-04-07 15:38:04 -0700 | [diff] [blame] | 81 | down_read(&zram->init_lock); |
| 82 | val = init_done(zram); |
| 83 | up_read(&zram->init_lock); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 84 | |
Sergey Senozhatsky | 56b4e8c | 2014-04-07 15:38:22 -0700 | [diff] [blame] | 85 | return scnprintf(buf, PAGE_SIZE, "%u\n", val); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 86 | } |
| 87 | |
| 88 | static ssize_t orig_data_size_show(struct device *dev, |
| 89 | struct device_attribute *attr, char *buf) |
| 90 | { |
| 91 | struct zram *zram = dev_to_zram(dev); |
| 92 | |
Sergey Senozhatsky | 56b4e8c | 2014-04-07 15:38:22 -0700 | [diff] [blame] | 93 | return scnprintf(buf, PAGE_SIZE, "%llu\n", |
Sergey Senozhatsky | 90a7806 | 2014-04-07 15:38:03 -0700 | [diff] [blame] | 94 | (u64)(atomic64_read(&zram->stats.pages_stored)) << PAGE_SHIFT); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 95 | } |
| 96 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 97 | static ssize_t mem_used_total_show(struct device *dev, |
| 98 | struct device_attribute *attr, char *buf) |
| 99 | { |
| 100 | u64 val = 0; |
| 101 | struct zram *zram = dev_to_zram(dev); |
| 102 | struct zram_meta *meta = zram->meta; |
| 103 | |
| 104 | down_read(&zram->init_lock); |
Sergey Senozhatsky | be2d1d5 | 2014-04-07 15:38:00 -0700 | [diff] [blame] | 105 | if (init_done(zram)) |
Minchan Kim | 722cdc1 | 2014-10-09 15:29:50 -0700 | [diff] [blame^] | 106 | val = zs_get_total_pages(meta->mem_pool); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 107 | up_read(&zram->init_lock); |
| 108 | |
Minchan Kim | 722cdc1 | 2014-10-09 15:29:50 -0700 | [diff] [blame^] | 109 | return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 110 | } |
| 111 | |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 112 | static ssize_t max_comp_streams_show(struct device *dev, |
| 113 | struct device_attribute *attr, char *buf) |
| 114 | { |
| 115 | int val; |
| 116 | struct zram *zram = dev_to_zram(dev); |
| 117 | |
| 118 | down_read(&zram->init_lock); |
| 119 | val = zram->max_comp_streams; |
| 120 | up_read(&zram->init_lock); |
| 121 | |
Sergey Senozhatsky | 56b4e8c | 2014-04-07 15:38:22 -0700 | [diff] [blame] | 122 | return scnprintf(buf, PAGE_SIZE, "%d\n", val); |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 123 | } |
| 124 | |
| 125 | static ssize_t max_comp_streams_store(struct device *dev, |
| 126 | struct device_attribute *attr, const char *buf, size_t len) |
| 127 | { |
| 128 | int num; |
| 129 | struct zram *zram = dev_to_zram(dev); |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 130 | int ret; |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 131 | |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 132 | ret = kstrtoint(buf, 0, &num); |
| 133 | if (ret < 0) |
| 134 | return ret; |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 135 | if (num < 1) |
| 136 | return -EINVAL; |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 137 | |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 138 | down_write(&zram->init_lock); |
| 139 | if (init_done(zram)) { |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 140 | if (!zcomp_set_max_streams(zram->comp, num)) { |
Sergey Senozhatsky | fe8eb12 | 2014-04-07 15:38:15 -0700 | [diff] [blame] | 141 | pr_info("Cannot change max compression streams\n"); |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 142 | ret = -EINVAL; |
| 143 | goto out; |
| 144 | } |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 145 | } |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 146 | |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 147 | zram->max_comp_streams = num; |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 148 | ret = len; |
| 149 | out: |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 150 | up_write(&zram->init_lock); |
Minchan Kim | 60a726e | 2014-04-07 15:38:21 -0700 | [diff] [blame] | 151 | return ret; |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 152 | } |
| 153 | |
Sergey Senozhatsky | e46b8a0 | 2014-04-07 15:38:17 -0700 | [diff] [blame] | 154 | static ssize_t comp_algorithm_show(struct device *dev, |
| 155 | struct device_attribute *attr, char *buf) |
| 156 | { |
| 157 | size_t sz; |
| 158 | struct zram *zram = dev_to_zram(dev); |
| 159 | |
| 160 | down_read(&zram->init_lock); |
| 161 | sz = zcomp_available_show(zram->compressor, buf); |
| 162 | up_read(&zram->init_lock); |
| 163 | |
| 164 | return sz; |
| 165 | } |
| 166 | |
| 167 | static ssize_t comp_algorithm_store(struct device *dev, |
| 168 | struct device_attribute *attr, const char *buf, size_t len) |
| 169 | { |
| 170 | struct zram *zram = dev_to_zram(dev); |
| 171 | down_write(&zram->init_lock); |
| 172 | if (init_done(zram)) { |
| 173 | up_write(&zram->init_lock); |
| 174 | pr_info("Can't change algorithm for initialized device\n"); |
| 175 | return -EBUSY; |
| 176 | } |
| 177 | strlcpy(zram->compressor, buf, sizeof(zram->compressor)); |
| 178 | up_write(&zram->init_lock); |
| 179 | return len; |
| 180 | } |
| 181 | |
Minchan Kim | 9296747 | 2014-01-30 15:46:03 -0800 | [diff] [blame] | 182 | /* flag operations needs meta->tb_lock */ |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 183 | static int zram_test_flag(struct zram_meta *meta, u32 index, |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 184 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 185 | { |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 186 | return meta->table[index].value & BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 187 | } |
| 188 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 189 | static void zram_set_flag(struct zram_meta *meta, u32 index, |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 190 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 191 | { |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 192 | meta->table[index].value |= BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 193 | } |
| 194 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 195 | static void zram_clear_flag(struct zram_meta *meta, u32 index, |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 196 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 197 | { |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 198 | meta->table[index].value &= ~BIT(flag); |
| 199 | } |
| 200 | |
| 201 | static size_t zram_get_obj_size(struct zram_meta *meta, u32 index) |
| 202 | { |
| 203 | return meta->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1); |
| 204 | } |
| 205 | |
| 206 | static void zram_set_obj_size(struct zram_meta *meta, |
| 207 | u32 index, size_t size) |
| 208 | { |
| 209 | unsigned long flags = meta->table[index].value >> ZRAM_FLAG_SHIFT; |
| 210 | |
| 211 | meta->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 212 | } |
| 213 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 214 | static inline int is_partial_io(struct bio_vec *bvec) |
| 215 | { |
| 216 | return bvec->bv_len != PAGE_SIZE; |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * Check if request is within bounds and aligned on zram logical blocks. |
| 221 | */ |
| 222 | static inline int valid_io_request(struct zram *zram, struct bio *bio) |
| 223 | { |
| 224 | u64 start, end, bound; |
Kumar Gaurav | a539c72 | 2013-08-08 23:53:24 +0530 | [diff] [blame] | 225 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 226 | /* unaligned request */ |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 227 | if (unlikely(bio->bi_iter.bi_sector & |
| 228 | (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1))) |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 229 | return 0; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 230 | if (unlikely(bio->bi_iter.bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1))) |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 231 | return 0; |
| 232 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 233 | start = bio->bi_iter.bi_sector; |
| 234 | end = start + (bio->bi_iter.bi_size >> SECTOR_SHIFT); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 235 | bound = zram->disksize >> SECTOR_SHIFT; |
| 236 | /* out of range range */ |
Sergey Senozhatsky | 75c7caf | 2013-06-22 17:21:00 +0300 | [diff] [blame] | 237 | if (unlikely(start >= bound || end > bound || start > end)) |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 238 | return 0; |
| 239 | |
| 240 | /* I/O request is valid */ |
| 241 | return 1; |
| 242 | } |
| 243 | |
| 244 | static void zram_meta_free(struct zram_meta *meta) |
| 245 | { |
| 246 | zs_destroy_pool(meta->mem_pool); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 247 | vfree(meta->table); |
| 248 | kfree(meta); |
| 249 | } |
| 250 | |
| 251 | static struct zram_meta *zram_meta_alloc(u64 disksize) |
| 252 | { |
| 253 | size_t num_pages; |
| 254 | struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL); |
| 255 | if (!meta) |
| 256 | goto out; |
| 257 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 258 | num_pages = disksize >> PAGE_SHIFT; |
| 259 | meta->table = vzalloc(num_pages * sizeof(*meta->table)); |
| 260 | if (!meta->table) { |
| 261 | pr_err("Error allocating zram address table\n"); |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 262 | goto free_meta; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 263 | } |
| 264 | |
| 265 | meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); |
| 266 | if (!meta->mem_pool) { |
| 267 | pr_err("Error creating memory pool\n"); |
| 268 | goto free_table; |
| 269 | } |
| 270 | |
| 271 | return meta; |
| 272 | |
| 273 | free_table: |
| 274 | vfree(meta->table); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 275 | free_meta: |
| 276 | kfree(meta); |
| 277 | meta = NULL; |
| 278 | out: |
| 279 | return meta; |
| 280 | } |
| 281 | |
| 282 | static void update_position(u32 *index, int *offset, struct bio_vec *bvec) |
| 283 | { |
| 284 | if (*offset + bvec->bv_len >= PAGE_SIZE) |
| 285 | (*index)++; |
| 286 | *offset = (*offset + bvec->bv_len) % PAGE_SIZE; |
| 287 | } |
| 288 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 289 | static int page_zero_filled(void *ptr) |
| 290 | { |
| 291 | unsigned int pos; |
| 292 | unsigned long *page; |
| 293 | |
| 294 | page = (unsigned long *)ptr; |
| 295 | |
| 296 | for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) { |
| 297 | if (page[pos]) |
| 298 | return 0; |
| 299 | } |
| 300 | |
| 301 | return 1; |
| 302 | } |
| 303 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 304 | static void handle_zero_page(struct bio_vec *bvec) |
| 305 | { |
| 306 | struct page *page = bvec->bv_page; |
| 307 | void *user_mem; |
| 308 | |
| 309 | user_mem = kmap_atomic(page); |
| 310 | if (is_partial_io(bvec)) |
| 311 | memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); |
| 312 | else |
| 313 | clear_page(user_mem); |
| 314 | kunmap_atomic(user_mem); |
| 315 | |
| 316 | flush_dcache_page(page); |
| 317 | } |
| 318 | |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 319 | |
| 320 | /* |
| 321 | * To protect concurrent access to the same index entry, |
| 322 | * caller should hold this table index entry's bit_spinlock to |
| 323 | * indicate this index entry is accessing. |
| 324 | */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 325 | static void zram_free_page(struct zram *zram, size_t index) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 326 | { |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 327 | struct zram_meta *meta = zram->meta; |
| 328 | unsigned long handle = meta->table[index].handle; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 329 | |
Nitin Gupta | fd1a30d | 2012-01-09 16:51:59 -0600 | [diff] [blame] | 330 | if (unlikely(!handle)) { |
Nitin Gupta | 2e88228 | 2010-01-28 21:13:41 +0530 | [diff] [blame] | 331 | /* |
| 332 | * No memory is allocated for zero filled pages. |
| 333 | * Simply clear zero page flag. |
| 334 | */ |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 335 | if (zram_test_flag(meta, index, ZRAM_ZERO)) { |
| 336 | zram_clear_flag(meta, index, ZRAM_ZERO); |
Sergey Senozhatsky | 90a7806 | 2014-04-07 15:38:03 -0700 | [diff] [blame] | 337 | atomic64_dec(&zram->stats.zero_pages); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 338 | } |
| 339 | return; |
| 340 | } |
| 341 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 342 | zs_free(meta->mem_pool, handle); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 343 | |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 344 | atomic64_sub(zram_get_obj_size(meta, index), |
| 345 | &zram->stats.compr_data_size); |
Sergey Senozhatsky | 90a7806 | 2014-04-07 15:38:03 -0700 | [diff] [blame] | 346 | atomic64_dec(&zram->stats.pages_stored); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 347 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 348 | meta->table[index].handle = 0; |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 349 | zram_set_obj_size(meta, index, 0); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 350 | } |
| 351 | |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 352 | static int zram_decompress_page(struct zram *zram, char *mem, u32 index) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 353 | { |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 354 | int ret = 0; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 355 | unsigned char *cmem; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 356 | struct zram_meta *meta = zram->meta; |
Minchan Kim | 9296747 | 2014-01-30 15:46:03 -0800 | [diff] [blame] | 357 | unsigned long handle; |
Minchan Kim | 023b409 | 2014-08-06 16:08:29 -0700 | [diff] [blame] | 358 | size_t size; |
Minchan Kim | 9296747 | 2014-01-30 15:46:03 -0800 | [diff] [blame] | 359 | |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 360 | bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); |
Minchan Kim | 9296747 | 2014-01-30 15:46:03 -0800 | [diff] [blame] | 361 | handle = meta->table[index].handle; |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 362 | size = zram_get_obj_size(meta, index); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 363 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 364 | if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) { |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 365 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 366 | clear_page(mem); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 367 | return 0; |
| 368 | } |
| 369 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 370 | cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO); |
Minchan Kim | 9296747 | 2014-01-30 15:46:03 -0800 | [diff] [blame] | 371 | if (size == PAGE_SIZE) |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 372 | copy_page(mem, cmem); |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 373 | else |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 374 | ret = zcomp_decompress(zram->comp, cmem, size, mem); |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 375 | zs_unmap_object(meta->mem_pool, handle); |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 376 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 377 | |
| 378 | /* Should NEVER happen. Return bio error if it does. */ |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 379 | if (unlikely(ret)) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 380 | pr_err("Decompression failed! err=%d, page=%u\n", ret, index); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 381 | return ret; |
| 382 | } |
| 383 | |
| 384 | return 0; |
| 385 | } |
| 386 | |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 387 | static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, |
| 388 | u32 index, int offset, struct bio *bio) |
| 389 | { |
| 390 | int ret; |
| 391 | struct page *page; |
| 392 | unsigned char *user_mem, *uncmem = NULL; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 393 | struct zram_meta *meta = zram->meta; |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 394 | page = bvec->bv_page; |
| 395 | |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 396 | bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 397 | if (unlikely(!meta->table[index].handle) || |
| 398 | zram_test_flag(meta, index, ZRAM_ZERO)) { |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 399 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 400 | handle_zero_page(bvec); |
| 401 | return 0; |
| 402 | } |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 403 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 404 | |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 405 | if (is_partial_io(bvec)) |
| 406 | /* Use a temporary buffer to decompress the page */ |
Minchan Kim | 7e5a510 | 2013-01-30 11:41:39 +0900 | [diff] [blame] | 407 | uncmem = kmalloc(PAGE_SIZE, GFP_NOIO); |
| 408 | |
| 409 | user_mem = kmap_atomic(page); |
| 410 | if (!is_partial_io(bvec)) |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 411 | uncmem = user_mem; |
| 412 | |
| 413 | if (!uncmem) { |
| 414 | pr_info("Unable to allocate temp memory\n"); |
| 415 | ret = -ENOMEM; |
| 416 | goto out_cleanup; |
| 417 | } |
| 418 | |
| 419 | ret = zram_decompress_page(zram, uncmem, index); |
| 420 | /* Should NEVER happen. Return bio error if it does. */ |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 421 | if (unlikely(ret)) |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 422 | goto out_cleanup; |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 423 | |
| 424 | if (is_partial_io(bvec)) |
| 425 | memcpy(user_mem + bvec->bv_offset, uncmem + offset, |
| 426 | bvec->bv_len); |
| 427 | |
| 428 | flush_dcache_page(page); |
| 429 | ret = 0; |
| 430 | out_cleanup: |
| 431 | kunmap_atomic(user_mem); |
| 432 | if (is_partial_io(bvec)) |
| 433 | kfree(uncmem); |
| 434 | return ret; |
| 435 | } |
| 436 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 437 | static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, |
| 438 | int offset) |
| 439 | { |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 440 | int ret = 0; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 441 | size_t clen; |
Minchan Kim | c234434 | 2012-06-08 15:39:25 +0900 | [diff] [blame] | 442 | unsigned long handle; |
Minchan Kim | 130f315 | 2012-06-08 15:39:27 +0900 | [diff] [blame] | 443 | struct page *page; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 444 | unsigned char *user_mem, *cmem, *src, *uncmem = NULL; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 445 | struct zram_meta *meta = zram->meta; |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 446 | struct zcomp_strm *zstrm; |
Minchan Kim | e46e331 | 2014-01-30 15:46:06 -0800 | [diff] [blame] | 447 | bool locked = false; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 448 | |
| 449 | page = bvec->bv_page; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 450 | if (is_partial_io(bvec)) { |
| 451 | /* |
| 452 | * This is a partial IO. We need to read the full page |
| 453 | * before to write the changes. |
| 454 | */ |
Minchan Kim | 7e5a510 | 2013-01-30 11:41:39 +0900 | [diff] [blame] | 455 | uncmem = kmalloc(PAGE_SIZE, GFP_NOIO); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 456 | if (!uncmem) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 457 | ret = -ENOMEM; |
| 458 | goto out; |
| 459 | } |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 460 | ret = zram_decompress_page(zram, uncmem, index); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 461 | if (ret) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 462 | goto out; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 463 | } |
| 464 | |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 465 | zstrm = zcomp_strm_find(zram->comp); |
Minchan Kim | e46e331 | 2014-01-30 15:46:06 -0800 | [diff] [blame] | 466 | locked = true; |
Cong Wang | ba82fe2 | 2011-11-25 23:14:25 +0800 | [diff] [blame] | 467 | user_mem = kmap_atomic(page); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 468 | |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 469 | if (is_partial_io(bvec)) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 470 | memcpy(uncmem + offset, user_mem + bvec->bv_offset, |
| 471 | bvec->bv_len); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 472 | kunmap_atomic(user_mem); |
| 473 | user_mem = NULL; |
| 474 | } else { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 475 | uncmem = user_mem; |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 476 | } |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 477 | |
| 478 | if (page_zero_filled(uncmem)) { |
Cong Wang | ba82fe2 | 2011-11-25 23:14:25 +0800 | [diff] [blame] | 479 | kunmap_atomic(user_mem); |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 480 | /* Free memory associated with this sector now. */ |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 481 | bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 482 | zram_free_page(zram, index); |
Minchan Kim | 9296747 | 2014-01-30 15:46:03 -0800 | [diff] [blame] | 483 | zram_set_flag(meta, index, ZRAM_ZERO); |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 484 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 485 | |
Sergey Senozhatsky | 90a7806 | 2014-04-07 15:38:03 -0700 | [diff] [blame] | 486 | atomic64_inc(&zram->stats.zero_pages); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 487 | ret = 0; |
| 488 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 489 | } |
| 490 | |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 491 | ret = zcomp_compress(zram->comp, zstrm, uncmem, &clen); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 492 | if (!is_partial_io(bvec)) { |
| 493 | kunmap_atomic(user_mem); |
| 494 | user_mem = NULL; |
| 495 | uncmem = NULL; |
| 496 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 497 | |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 498 | if (unlikely(ret)) { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 499 | pr_err("Compression failed! err=%d\n", ret); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 500 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 501 | } |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 502 | src = zstrm->buffer; |
Nitin Gupta | c8f2f0d | 2012-10-10 17:42:18 -0700 | [diff] [blame] | 503 | if (unlikely(clen > max_zpage_size)) { |
Nitin Gupta | c8f2f0d | 2012-10-10 17:42:18 -0700 | [diff] [blame] | 504 | clen = PAGE_SIZE; |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 505 | if (is_partial_io(bvec)) |
| 506 | src = uncmem; |
Nitin Gupta | c8f2f0d | 2012-10-10 17:42:18 -0700 | [diff] [blame] | 507 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 508 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 509 | handle = zs_malloc(meta->mem_pool, clen); |
Nitin Gupta | fd1a30d | 2012-01-09 16:51:59 -0600 | [diff] [blame] | 510 | if (!handle) { |
Marlies Ruck | 596b3dd | 2013-05-16 14:30:39 -0400 | [diff] [blame] | 511 | pr_info("Error allocating memory for compressed page: %u, size=%zu\n", |
| 512 | index, clen); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 513 | ret = -ENOMEM; |
| 514 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 515 | } |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 516 | cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 517 | |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 518 | if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) { |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 519 | src = kmap_atomic(page); |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 520 | copy_page(cmem, src); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 521 | kunmap_atomic(src); |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 522 | } else { |
| 523 | memcpy(cmem, src, clen); |
| 524 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 525 | |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 526 | zcomp_strm_release(zram->comp, zstrm); |
| 527 | locked = false; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 528 | zs_unmap_object(meta->mem_pool, handle); |
Nitin Gupta | fd1a30d | 2012-01-09 16:51:59 -0600 | [diff] [blame] | 529 | |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 530 | /* |
| 531 | * Free memory associated with this sector |
| 532 | * before overwriting unused sectors. |
| 533 | */ |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 534 | bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 535 | zram_free_page(zram, index); |
| 536 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 537 | meta->table[index].handle = handle; |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 538 | zram_set_obj_size(meta, index, clen); |
| 539 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 540 | |
| 541 | /* Update stats */ |
Sergey Senozhatsky | 90a7806 | 2014-04-07 15:38:03 -0700 | [diff] [blame] | 542 | atomic64_add(clen, &zram->stats.compr_data_size); |
| 543 | atomic64_inc(&zram->stats.pages_stored); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 544 | out: |
Minchan Kim | e46e331 | 2014-01-30 15:46:06 -0800 | [diff] [blame] | 545 | if (locked) |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 546 | zcomp_strm_release(zram->comp, zstrm); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 547 | if (is_partial_io(bvec)) |
| 548 | kfree(uncmem); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 549 | return ret; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 550 | } |
| 551 | |
| 552 | static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 553 | int offset, struct bio *bio) |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 554 | { |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 555 | int ret; |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 556 | int rw = bio_data_dir(bio); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 557 | |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 558 | if (rw == READ) { |
| 559 | atomic64_inc(&zram->stats.num_reads); |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 560 | ret = zram_bvec_read(zram, bvec, index, offset, bio); |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 561 | } else { |
| 562 | atomic64_inc(&zram->stats.num_writes); |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 563 | ret = zram_bvec_write(zram, bvec, index, offset); |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 564 | } |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 565 | |
Chao Yu | 0cf1e9d | 2014-08-29 15:18:37 -0700 | [diff] [blame] | 566 | if (unlikely(ret)) { |
| 567 | if (rw == READ) |
| 568 | atomic64_inc(&zram->stats.failed_reads); |
| 569 | else |
| 570 | atomic64_inc(&zram->stats.failed_writes); |
| 571 | } |
| 572 | |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 573 | return ret; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 574 | } |
| 575 | |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 576 | /* |
| 577 | * zram_bio_discard - handler on discard request |
| 578 | * @index: physical block index in PAGE_SIZE units |
| 579 | * @offset: byte offset within physical block |
| 580 | */ |
| 581 | static void zram_bio_discard(struct zram *zram, u32 index, |
| 582 | int offset, struct bio *bio) |
| 583 | { |
| 584 | size_t n = bio->bi_iter.bi_size; |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 585 | struct zram_meta *meta = zram->meta; |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 586 | |
| 587 | /* |
| 588 | * zram manages data in physical block size units. Because logical block |
| 589 | * size isn't identical with physical block size on some arch, we |
| 590 | * could get a discard request pointing to a specific offset within a |
| 591 | * certain physical block. Although we can handle this request by |
| 592 | * reading that physiclal block and decompressing and partially zeroing |
| 593 | * and re-compressing and then re-storing it, this isn't reasonable |
| 594 | * because our intent with a discard request is to save memory. So |
| 595 | * skipping this logical block is appropriate here. |
| 596 | */ |
| 597 | if (offset) { |
Weijie Yang | 38515c7 | 2014-06-04 16:11:06 -0700 | [diff] [blame] | 598 | if (n <= (PAGE_SIZE - offset)) |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 599 | return; |
| 600 | |
Weijie Yang | 38515c7 | 2014-06-04 16:11:06 -0700 | [diff] [blame] | 601 | n -= (PAGE_SIZE - offset); |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 602 | index++; |
| 603 | } |
| 604 | |
| 605 | while (n >= PAGE_SIZE) { |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 606 | bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 607 | zram_free_page(zram, index); |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 608 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 609 | index++; |
| 610 | n -= PAGE_SIZE; |
| 611 | } |
| 612 | } |
| 613 | |
Minchan Kim | 2b86ab9 | 2013-08-12 15:13:55 +0900 | [diff] [blame] | 614 | static void zram_reset_device(struct zram *zram, bool reset_capacity) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 615 | { |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 616 | size_t index; |
| 617 | struct zram_meta *meta; |
| 618 | |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 619 | down_write(&zram->init_lock); |
Sergey Senozhatsky | be2d1d5 | 2014-04-07 15:38:00 -0700 | [diff] [blame] | 620 | if (!init_done(zram)) { |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 621 | up_write(&zram->init_lock); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 622 | return; |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 623 | } |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 624 | |
| 625 | meta = zram->meta; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 626 | /* Free all pages that are still in this zram device */ |
| 627 | for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { |
| 628 | unsigned long handle = meta->table[index].handle; |
| 629 | if (!handle) |
| 630 | continue; |
| 631 | |
| 632 | zs_free(meta->mem_pool, handle); |
| 633 | } |
| 634 | |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 635 | zcomp_destroy(zram->comp); |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 636 | zram->max_comp_streams = 1; |
| 637 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 638 | zram_meta_free(zram->meta); |
| 639 | zram->meta = NULL; |
| 640 | /* Reset stats */ |
| 641 | memset(&zram->stats, 0, sizeof(zram->stats)); |
| 642 | |
| 643 | zram->disksize = 0; |
Minchan Kim | b4c5c60 | 2014-07-23 14:00:04 -0700 | [diff] [blame] | 644 | if (reset_capacity) |
Minchan Kim | 2b86ab9 | 2013-08-12 15:13:55 +0900 | [diff] [blame] | 645 | set_capacity(zram->disk, 0); |
Minchan Kim | b4c5c60 | 2014-07-23 14:00:04 -0700 | [diff] [blame] | 646 | |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 647 | up_write(&zram->init_lock); |
Minchan Kim | b4c5c60 | 2014-07-23 14:00:04 -0700 | [diff] [blame] | 648 | |
| 649 | /* |
| 650 | * Revalidate disk out of the init_lock to avoid lockdep splat. |
| 651 | * It's okay because disk's capacity is protected by init_lock |
| 652 | * so that revalidate_disk always sees up-to-date capacity. |
| 653 | */ |
| 654 | if (reset_capacity) |
| 655 | revalidate_disk(zram->disk); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 656 | } |
| 657 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 658 | static ssize_t disksize_store(struct device *dev, |
| 659 | struct device_attribute *attr, const char *buf, size_t len) |
| 660 | { |
| 661 | u64 disksize; |
Sergey Senozhatsky | d61f98c | 2014-04-07 15:38:19 -0700 | [diff] [blame] | 662 | struct zcomp *comp; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 663 | struct zram_meta *meta; |
| 664 | struct zram *zram = dev_to_zram(dev); |
Sergey Senozhatsky | fcfa8d9 | 2014-04-07 15:38:20 -0700 | [diff] [blame] | 665 | int err; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 666 | |
| 667 | disksize = memparse(buf, NULL); |
| 668 | if (!disksize) |
| 669 | return -EINVAL; |
| 670 | |
| 671 | disksize = PAGE_ALIGN(disksize); |
| 672 | meta = zram_meta_alloc(disksize); |
Minchan Kim | db5d711 | 2014-03-03 15:38:34 -0800 | [diff] [blame] | 673 | if (!meta) |
| 674 | return -ENOMEM; |
Sergey Senozhatsky | b67d1ec | 2014-04-07 15:38:09 -0700 | [diff] [blame] | 675 | |
Sergey Senozhatsky | d61f98c | 2014-04-07 15:38:19 -0700 | [diff] [blame] | 676 | comp = zcomp_create(zram->compressor, zram->max_comp_streams); |
Sergey Senozhatsky | fcfa8d9 | 2014-04-07 15:38:20 -0700 | [diff] [blame] | 677 | if (IS_ERR(comp)) { |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 678 | pr_info("Cannot initialise %s compressing backend\n", |
Sergey Senozhatsky | e46b8a0 | 2014-04-07 15:38:17 -0700 | [diff] [blame] | 679 | zram->compressor); |
Sergey Senozhatsky | fcfa8d9 | 2014-04-07 15:38:20 -0700 | [diff] [blame] | 680 | err = PTR_ERR(comp); |
| 681 | goto out_free_meta; |
Sergey Senozhatsky | d61f98c | 2014-04-07 15:38:19 -0700 | [diff] [blame] | 682 | } |
| 683 | |
| 684 | down_write(&zram->init_lock); |
| 685 | if (init_done(zram)) { |
Sergey Senozhatsky | d61f98c | 2014-04-07 15:38:19 -0700 | [diff] [blame] | 686 | pr_info("Cannot change disksize for initialized device\n"); |
| 687 | err = -EBUSY; |
Sergey Senozhatsky | fcfa8d9 | 2014-04-07 15:38:20 -0700 | [diff] [blame] | 688 | goto out_destroy_comp; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 689 | } |
| 690 | |
Sergey Senozhatsky | b67d1ec | 2014-04-07 15:38:09 -0700 | [diff] [blame] | 691 | zram->meta = meta; |
Sergey Senozhatsky | d61f98c | 2014-04-07 15:38:19 -0700 | [diff] [blame] | 692 | zram->comp = comp; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 693 | zram->disksize = disksize; |
| 694 | set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 695 | up_write(&zram->init_lock); |
Minchan Kim | b4c5c60 | 2014-07-23 14:00:04 -0700 | [diff] [blame] | 696 | |
| 697 | /* |
| 698 | * Revalidate disk out of the init_lock to avoid lockdep splat. |
| 699 | * It's okay because disk's capacity is protected by init_lock |
| 700 | * so that revalidate_disk always sees up-to-date capacity. |
| 701 | */ |
| 702 | revalidate_disk(zram->disk); |
| 703 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 704 | return len; |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 705 | |
Sergey Senozhatsky | fcfa8d9 | 2014-04-07 15:38:20 -0700 | [diff] [blame] | 706 | out_destroy_comp: |
| 707 | up_write(&zram->init_lock); |
| 708 | zcomp_destroy(comp); |
| 709 | out_free_meta: |
Sergey Senozhatsky | b7ca232 | 2014-04-07 15:38:12 -0700 | [diff] [blame] | 710 | zram_meta_free(meta); |
| 711 | return err; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 712 | } |
| 713 | |
| 714 | static ssize_t reset_store(struct device *dev, |
| 715 | struct device_attribute *attr, const char *buf, size_t len) |
| 716 | { |
| 717 | int ret; |
| 718 | unsigned short do_reset; |
| 719 | struct zram *zram; |
| 720 | struct block_device *bdev; |
| 721 | |
| 722 | zram = dev_to_zram(dev); |
| 723 | bdev = bdget_disk(zram->disk, 0); |
| 724 | |
Rashika Kheria | 46a51c8 | 2013-10-30 18:36:32 +0530 | [diff] [blame] | 725 | if (!bdev) |
| 726 | return -ENOMEM; |
| 727 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 728 | /* Do not reset an active device! */ |
Rashika Kheria | 1b67222 | 2013-11-10 22:13:53 +0530 | [diff] [blame] | 729 | if (bdev->bd_holders) { |
| 730 | ret = -EBUSY; |
| 731 | goto out; |
| 732 | } |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 733 | |
| 734 | ret = kstrtou16(buf, 10, &do_reset); |
| 735 | if (ret) |
Rashika Kheria | 1b67222 | 2013-11-10 22:13:53 +0530 | [diff] [blame] | 736 | goto out; |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 737 | |
Rashika Kheria | 1b67222 | 2013-11-10 22:13:53 +0530 | [diff] [blame] | 738 | if (!do_reset) { |
| 739 | ret = -EINVAL; |
| 740 | goto out; |
| 741 | } |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 742 | |
| 743 | /* Make sure all pending I/O is finished */ |
Rashika Kheria | 46a51c8 | 2013-10-30 18:36:32 +0530 | [diff] [blame] | 744 | fsync_bdev(bdev); |
Rashika Kheria | 1b67222 | 2013-11-10 22:13:53 +0530 | [diff] [blame] | 745 | bdput(bdev); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 746 | |
Minchan Kim | 2b86ab9 | 2013-08-12 15:13:55 +0900 | [diff] [blame] | 747 | zram_reset_device(zram, true); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 748 | return len; |
Rashika Kheria | 1b67222 | 2013-11-10 22:13:53 +0530 | [diff] [blame] | 749 | |
| 750 | out: |
| 751 | bdput(bdev); |
| 752 | return ret; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 753 | } |
| 754 | |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 755 | static void __zram_make_request(struct zram *zram, struct bio *bio) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 756 | { |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 757 | int offset; |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 758 | u32 index; |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 759 | struct bio_vec bvec; |
| 760 | struct bvec_iter iter; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 761 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 762 | index = bio->bi_iter.bi_sector >> SECTORS_PER_PAGE_SHIFT; |
| 763 | offset = (bio->bi_iter.bi_sector & |
| 764 | (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 765 | |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 766 | if (unlikely(bio->bi_rw & REQ_DISCARD)) { |
| 767 | zram_bio_discard(zram, index, offset, bio); |
| 768 | bio_endio(bio, 0); |
| 769 | return; |
| 770 | } |
| 771 | |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 772 | bio_for_each_segment(bvec, bio, iter) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 773 | int max_transfer_size = PAGE_SIZE - offset; |
| 774 | |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 775 | if (bvec.bv_len > max_transfer_size) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 776 | /* |
| 777 | * zram_bvec_rw() can only make operation on a single |
| 778 | * zram page. Split the bio vector. |
| 779 | */ |
| 780 | struct bio_vec bv; |
| 781 | |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 782 | bv.bv_page = bvec.bv_page; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 783 | bv.bv_len = max_transfer_size; |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 784 | bv.bv_offset = bvec.bv_offset; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 785 | |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 786 | if (zram_bvec_rw(zram, &bv, index, offset, bio) < 0) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 787 | goto out; |
| 788 | |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 789 | bv.bv_len = bvec.bv_len - max_transfer_size; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 790 | bv.bv_offset += max_transfer_size; |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 791 | if (zram_bvec_rw(zram, &bv, index + 1, 0, bio) < 0) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 792 | goto out; |
| 793 | } else |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 794 | if (zram_bvec_rw(zram, &bvec, index, offset, bio) < 0) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 795 | goto out; |
| 796 | |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 797 | update_position(&index, &offset, &bvec); |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 798 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 799 | |
| 800 | set_bit(BIO_UPTODATE, &bio->bi_flags); |
| 801 | bio_endio(bio, 0); |
Nitin Gupta | 7d7854b | 2011-01-22 07:36:15 -0500 | [diff] [blame] | 802 | return; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 803 | |
| 804 | out: |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 805 | bio_io_error(bio); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 806 | } |
| 807 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 808 | /* |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 809 | * Handler function for all zram I/O requests. |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 810 | */ |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 811 | static void zram_make_request(struct request_queue *queue, struct bio *bio) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 812 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 813 | struct zram *zram = queue->queuedata; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 814 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 815 | down_read(&zram->init_lock); |
Sergey Senozhatsky | be2d1d5 | 2014-04-07 15:38:00 -0700 | [diff] [blame] | 816 | if (unlikely(!init_done(zram))) |
Minchan Kim | 3de738c | 2013-01-30 11:41:41 +0900 | [diff] [blame] | 817 | goto error; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 818 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 819 | if (!valid_io_request(zram, bio)) { |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 820 | atomic64_inc(&zram->stats.invalid_io); |
Minchan Kim | 3de738c | 2013-01-30 11:41:41 +0900 | [diff] [blame] | 821 | goto error; |
Jerome Marchand | 6642a67 | 2011-02-17 17:11:49 +0100 | [diff] [blame] | 822 | } |
| 823 | |
Sergey Senozhatsky | be257c6 | 2014-04-07 15:38:01 -0700 | [diff] [blame] | 824 | __zram_make_request(zram, bio); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 825 | up_read(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 826 | |
Linus Torvalds | b4fdcb0 | 2011-11-04 17:06:58 -0700 | [diff] [blame] | 827 | return; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 828 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 829 | error: |
Minchan Kim | 3de738c | 2013-01-30 11:41:41 +0900 | [diff] [blame] | 830 | up_read(&zram->init_lock); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 831 | bio_io_error(bio); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 832 | } |
| 833 | |
Nitin Gupta | 2ccbec0 | 2011-09-09 19:01:00 -0400 | [diff] [blame] | 834 | static void zram_slot_free_notify(struct block_device *bdev, |
| 835 | unsigned long index) |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 836 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 837 | struct zram *zram; |
Minchan Kim | f614a9f | 2014-01-30 15:46:04 -0800 | [diff] [blame] | 838 | struct zram_meta *meta; |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 839 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 840 | zram = bdev->bd_disk->private_data; |
Minchan Kim | f614a9f | 2014-01-30 15:46:04 -0800 | [diff] [blame] | 841 | meta = zram->meta; |
| 842 | |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 843 | bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); |
Minchan Kim | f614a9f | 2014-01-30 15:46:04 -0800 | [diff] [blame] | 844 | zram_free_page(zram, index); |
Weijie Yang | d2d5e76 | 2014-08-06 16:08:31 -0700 | [diff] [blame] | 845 | bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 846 | atomic64_inc(&zram->stats.notify_free); |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 847 | } |
| 848 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 849 | static const struct block_device_operations zram_devops = { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 850 | .swap_slot_free_notify = zram_slot_free_notify, |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 851 | .owner = THIS_MODULE |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 852 | }; |
| 853 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 854 | static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR, |
| 855 | disksize_show, disksize_store); |
| 856 | static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL); |
| 857 | static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 858 | static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 859 | static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL); |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 860 | static DEVICE_ATTR(max_comp_streams, S_IRUGO | S_IWUSR, |
| 861 | max_comp_streams_show, max_comp_streams_store); |
Sergey Senozhatsky | e46b8a0 | 2014-04-07 15:38:17 -0700 | [diff] [blame] | 862 | static DEVICE_ATTR(comp_algorithm, S_IRUGO | S_IWUSR, |
| 863 | comp_algorithm_show, comp_algorithm_store); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 864 | |
Sergey Senozhatsky | a68eb3b | 2014-04-07 15:38:04 -0700 | [diff] [blame] | 865 | ZRAM_ATTR_RO(num_reads); |
| 866 | ZRAM_ATTR_RO(num_writes); |
Sergey Senozhatsky | 6444724 | 2014-04-07 15:38:05 -0700 | [diff] [blame] | 867 | ZRAM_ATTR_RO(failed_reads); |
| 868 | ZRAM_ATTR_RO(failed_writes); |
Sergey Senozhatsky | a68eb3b | 2014-04-07 15:38:04 -0700 | [diff] [blame] | 869 | ZRAM_ATTR_RO(invalid_io); |
| 870 | ZRAM_ATTR_RO(notify_free); |
| 871 | ZRAM_ATTR_RO(zero_pages); |
| 872 | ZRAM_ATTR_RO(compr_data_size); |
| 873 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 874 | static struct attribute *zram_disk_attrs[] = { |
| 875 | &dev_attr_disksize.attr, |
| 876 | &dev_attr_initstate.attr, |
| 877 | &dev_attr_reset.attr, |
| 878 | &dev_attr_num_reads.attr, |
| 879 | &dev_attr_num_writes.attr, |
Sergey Senozhatsky | 6444724 | 2014-04-07 15:38:05 -0700 | [diff] [blame] | 880 | &dev_attr_failed_reads.attr, |
| 881 | &dev_attr_failed_writes.attr, |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 882 | &dev_attr_invalid_io.attr, |
| 883 | &dev_attr_notify_free.attr, |
| 884 | &dev_attr_zero_pages.attr, |
| 885 | &dev_attr_orig_data_size.attr, |
| 886 | &dev_attr_compr_data_size.attr, |
| 887 | &dev_attr_mem_used_total.attr, |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 888 | &dev_attr_max_comp_streams.attr, |
Sergey Senozhatsky | e46b8a0 | 2014-04-07 15:38:17 -0700 | [diff] [blame] | 889 | &dev_attr_comp_algorithm.attr, |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 890 | NULL, |
| 891 | }; |
| 892 | |
| 893 | static struct attribute_group zram_disk_attr_group = { |
| 894 | .attrs = zram_disk_attrs, |
| 895 | }; |
| 896 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 897 | static int create_device(struct zram *zram, int device_id) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 898 | { |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 899 | int ret = -ENOMEM; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 900 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 901 | init_rwsem(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 902 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 903 | zram->queue = blk_alloc_queue(GFP_KERNEL); |
| 904 | if (!zram->queue) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 905 | pr_err("Error allocating disk queue for device %d\n", |
| 906 | device_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 907 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 908 | } |
| 909 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 910 | blk_queue_make_request(zram->queue, zram_make_request); |
| 911 | zram->queue->queuedata = zram; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 912 | |
| 913 | /* gendisk structure */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 914 | zram->disk = alloc_disk(1); |
| 915 | if (!zram->disk) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 916 | pr_warn("Error allocating disk structure for device %d\n", |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 917 | device_id); |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 918 | goto out_free_queue; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 919 | } |
| 920 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 921 | zram->disk->major = zram_major; |
| 922 | zram->disk->first_minor = device_id; |
| 923 | zram->disk->fops = &zram_devops; |
| 924 | zram->disk->queue = zram->queue; |
| 925 | zram->disk->private_data = zram; |
| 926 | snprintf(zram->disk->disk_name, 16, "zram%d", device_id); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 927 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 928 | /* Actual capacity set using syfs (/sys/block/zram<id>/disksize */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 929 | set_capacity(zram->disk, 0); |
Sergey Senozhatsky | b67d1ec | 2014-04-07 15:38:09 -0700 | [diff] [blame] | 930 | /* zram devices sort of resembles non-rotational disks */ |
| 931 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 932 | /* |
| 933 | * To ensure that we always get PAGE_SIZE aligned |
| 934 | * and n*PAGE_SIZED sized I/O requests. |
| 935 | */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 936 | blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE); |
Robert Jennings | 7b19b8d | 2011-01-28 08:58:17 -0600 | [diff] [blame] | 937 | blk_queue_logical_block_size(zram->disk->queue, |
| 938 | ZRAM_LOGICAL_BLOCK_SIZE); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 939 | blk_queue_io_min(zram->disk->queue, PAGE_SIZE); |
| 940 | blk_queue_io_opt(zram->disk->queue, PAGE_SIZE); |
Joonsoo Kim | f4659d8 | 2014-04-07 15:38:24 -0700 | [diff] [blame] | 941 | zram->disk->queue->limits.discard_granularity = PAGE_SIZE; |
| 942 | zram->disk->queue->limits.max_discard_sectors = UINT_MAX; |
| 943 | /* |
| 944 | * zram_bio_discard() will clear all logical blocks if logical block |
| 945 | * size is identical with physical block size(PAGE_SIZE). But if it is |
| 946 | * different, we will skip discarding some parts of logical blocks in |
| 947 | * the part of the request range which isn't aligned to physical block |
| 948 | * size. So we can't ensure that all discarded logical blocks are |
| 949 | * zeroed. |
| 950 | */ |
| 951 | if (ZRAM_LOGICAL_BLOCK_SIZE == PAGE_SIZE) |
| 952 | zram->disk->queue->limits.discard_zeroes_data = 1; |
| 953 | else |
| 954 | zram->disk->queue->limits.discard_zeroes_data = 0; |
| 955 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zram->disk->queue); |
Nitin Gupta | 5d83d5a | 2010-01-28 21:13:39 +0530 | [diff] [blame] | 956 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 957 | add_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 958 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 959 | ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj, |
| 960 | &zram_disk_attr_group); |
| 961 | if (ret < 0) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 962 | pr_warn("Error creating sysfs group"); |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 963 | goto out_free_disk; |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 964 | } |
Sergey Senozhatsky | e46b8a0 | 2014-04-07 15:38:17 -0700 | [diff] [blame] | 965 | strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor)); |
Sergey Senozhatsky | be2d1d5 | 2014-04-07 15:38:00 -0700 | [diff] [blame] | 966 | zram->meta = NULL; |
Sergey Senozhatsky | beca3ec | 2014-04-07 15:38:14 -0700 | [diff] [blame] | 967 | zram->max_comp_streams = 1; |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 968 | return 0; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 969 | |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 970 | out_free_disk: |
| 971 | del_gendisk(zram->disk); |
| 972 | put_disk(zram->disk); |
| 973 | out_free_queue: |
| 974 | blk_cleanup_queue(zram->queue); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 975 | out: |
| 976 | return ret; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 977 | } |
| 978 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 979 | static void destroy_device(struct zram *zram) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 980 | { |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 981 | sysfs_remove_group(&disk_to_dev(zram->disk)->kobj, |
| 982 | &zram_disk_attr_group); |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 983 | |
Rashika Kheria | 59d3fe5 | 2013-10-30 18:43:32 +0530 | [diff] [blame] | 984 | del_gendisk(zram->disk); |
| 985 | put_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 986 | |
Rashika Kheria | 59d3fe5 | 2013-10-30 18:43:32 +0530 | [diff] [blame] | 987 | blk_cleanup_queue(zram->queue); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 988 | } |
| 989 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 990 | static int __init zram_init(void) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 991 | { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 992 | int ret, dev_id; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 993 | |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 994 | if (num_devices > max_num_devices) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 995 | pr_warn("Invalid value for num_devices: %u\n", |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 996 | num_devices); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 997 | ret = -EINVAL; |
| 998 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 999 | } |
| 1000 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1001 | zram_major = register_blkdev(0, "zram"); |
| 1002 | if (zram_major <= 0) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 1003 | pr_warn("Unable to get major number\n"); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1004 | ret = -EBUSY; |
| 1005 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1006 | } |
| 1007 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1008 | /* Allocate the device array and initialize each one */ |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 1009 | zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL); |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 1010 | if (!zram_devices) { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1011 | ret = -ENOMEM; |
| 1012 | goto unregister; |
| 1013 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1014 | |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 1015 | for (dev_id = 0; dev_id < num_devices; dev_id++) { |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 1016 | ret = create_device(&zram_devices[dev_id], dev_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1017 | if (ret) |
Minchan Kim | 3bf040c | 2010-01-11 16:15:53 +0900 | [diff] [blame] | 1018 | goto free_devices; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1019 | } |
| 1020 | |
Davidlohr Bueso | ca3d70b | 2013-01-01 21:24:13 -0800 | [diff] [blame] | 1021 | pr_info("Created %u device(s) ...\n", num_devices); |
| 1022 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1023 | return 0; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1024 | |
Minchan Kim | 3bf040c | 2010-01-11 16:15:53 +0900 | [diff] [blame] | 1025 | free_devices: |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1026 | while (dev_id) |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 1027 | destroy_device(&zram_devices[--dev_id]); |
| 1028 | kfree(zram_devices); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1029 | unregister: |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1030 | unregister_blkdev(zram_major, "zram"); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 1031 | out: |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1032 | return ret; |
| 1033 | } |
| 1034 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1035 | static void __exit zram_exit(void) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1036 | { |
| 1037 | int i; |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1038 | struct zram *zram; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1039 | |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 1040 | for (i = 0; i < num_devices; i++) { |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 1041 | zram = &zram_devices[i]; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1042 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1043 | destroy_device(zram); |
Minchan Kim | 2b86ab9 | 2013-08-12 15:13:55 +0900 | [diff] [blame] | 1044 | /* |
| 1045 | * Shouldn't access zram->disk after destroy_device |
| 1046 | * because destroy_device already released zram->disk. |
| 1047 | */ |
| 1048 | zram_reset_device(zram, false); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1049 | } |
| 1050 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1051 | unregister_blkdev(zram_major, "zram"); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1052 | |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 1053 | kfree(zram_devices); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1054 | pr_debug("Cleanup done!\n"); |
| 1055 | } |
| 1056 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1057 | module_init(zram_init); |
| 1058 | module_exit(zram_exit); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1059 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 1060 | module_param(num_devices, uint, 0); |
| 1061 | MODULE_PARM_DESC(num_devices, "Number of zram devices"); |
| 1062 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1063 | MODULE_LICENSE("Dual BSD/GPL"); |
| 1064 | MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>"); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 1065 | MODULE_DESCRIPTION("Compressed RAM Block Device"); |