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 |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 5 | * |
| 6 | * This code is released using a dual license strategy: BSD/GPL |
| 7 | * You can choose the licence that better fits your requirements. |
| 8 | * |
| 9 | * Released under the terms of 3-clause BSD License |
| 10 | * Released under the terms of GNU General Public License Version 2.0 |
| 11 | * |
| 12 | * Project home: http://compcache.googlecode.com |
| 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/lzo.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 33 | #include <linux/string.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 34 | #include <linux/vmalloc.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; |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 40 | struct zram *zram_devices; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 41 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 42 | /* Module params (documentation at end) */ |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 43 | unsigned int zram_num_devices; |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 44 | |
| 45 | static void zram_stat_inc(u32 *v) |
| 46 | { |
| 47 | *v = *v + 1; |
| 48 | } |
| 49 | |
| 50 | static void zram_stat_dec(u32 *v) |
| 51 | { |
| 52 | *v = *v - 1; |
| 53 | } |
| 54 | |
| 55 | static void zram_stat64_add(struct zram *zram, u64 *v, u64 inc) |
| 56 | { |
| 57 | spin_lock(&zram->stat64_lock); |
| 58 | *v = *v + inc; |
| 59 | spin_unlock(&zram->stat64_lock); |
| 60 | } |
| 61 | |
| 62 | static void zram_stat64_sub(struct zram *zram, u64 *v, u64 dec) |
| 63 | { |
| 64 | spin_lock(&zram->stat64_lock); |
| 65 | *v = *v - dec; |
| 66 | spin_unlock(&zram->stat64_lock); |
| 67 | } |
| 68 | |
| 69 | static void zram_stat64_inc(struct zram *zram, u64 *v) |
| 70 | { |
| 71 | zram_stat64_add(zram, v, 1); |
| 72 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 73 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 74 | static int zram_test_flag(struct zram *zram, u32 index, |
| 75 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 76 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 77 | return zram->table[index].flags & BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 78 | } |
| 79 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 80 | static void zram_set_flag(struct zram *zram, u32 index, |
| 81 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 82 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 83 | zram->table[index].flags |= BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 84 | } |
| 85 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 86 | static void zram_clear_flag(struct zram *zram, u32 index, |
| 87 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 88 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 89 | zram->table[index].flags &= ~BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 90 | } |
| 91 | |
| 92 | static int page_zero_filled(void *ptr) |
| 93 | { |
| 94 | unsigned int pos; |
| 95 | unsigned long *page; |
| 96 | |
| 97 | page = (unsigned long *)ptr; |
| 98 | |
| 99 | for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) { |
| 100 | if (page[pos]) |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | return 1; |
| 105 | } |
| 106 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 107 | static void zram_set_disksize(struct zram *zram, size_t totalram_bytes) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 108 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 109 | if (!zram->disksize) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 110 | pr_info( |
| 111 | "disk size not provided. You can use disksize_kb module " |
| 112 | "param to specify size.\nUsing default: (%u%% of RAM).\n", |
| 113 | default_disksize_perc_ram |
| 114 | ); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 115 | zram->disksize = default_disksize_perc_ram * |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 116 | (totalram_bytes / 100); |
| 117 | } |
| 118 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 119 | if (zram->disksize > 2 * (totalram_bytes)) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 120 | pr_info( |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 121 | "There is little point creating a zram of greater than " |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 122 | "twice the size of memory since we expect a 2:1 compression " |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 123 | "ratio. Note that zram uses about 0.1%% of the size of " |
| 124 | "the disk when not in use so a huge zram is " |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 125 | "wasteful.\n" |
| 126 | "\tMemory Size: %zu kB\n" |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 127 | "\tSize you selected: %llu kB\n" |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 128 | "Continuing anyway ...\n", |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 129 | totalram_bytes >> 10, zram->disksize |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 130 | ); |
| 131 | } |
| 132 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 133 | zram->disksize &= PAGE_MASK; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 134 | } |
| 135 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 136 | static void zram_free_page(struct zram *zram, size_t index) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 137 | { |
| 138 | u32 clen; |
| 139 | void *obj; |
| 140 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 141 | struct page *page = zram->table[index].page; |
| 142 | u32 offset = zram->table[index].offset; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 143 | |
| 144 | if (unlikely(!page)) { |
Nitin Gupta | 2e88228 | 2010-01-28 21:13:41 +0530 | [diff] [blame] | 145 | /* |
| 146 | * No memory is allocated for zero filled pages. |
| 147 | * Simply clear zero page flag. |
| 148 | */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 149 | if (zram_test_flag(zram, index, ZRAM_ZERO)) { |
| 150 | zram_clear_flag(zram, index, ZRAM_ZERO); |
| 151 | zram_stat_dec(&zram->stats.pages_zero); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 152 | } |
| 153 | return; |
| 154 | } |
| 155 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 156 | if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 157 | clen = PAGE_SIZE; |
| 158 | __free_page(page); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 159 | zram_clear_flag(zram, index, ZRAM_UNCOMPRESSED); |
| 160 | zram_stat_dec(&zram->stats.pages_expand); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 161 | goto out; |
| 162 | } |
| 163 | |
| 164 | obj = kmap_atomic(page, KM_USER0) + offset; |
| 165 | clen = xv_get_object_size(obj) - sizeof(struct zobj_header); |
| 166 | kunmap_atomic(obj, KM_USER0); |
| 167 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 168 | xv_free(zram->mem_pool, page, offset); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 169 | if (clen <= PAGE_SIZE / 2) |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 170 | zram_stat_dec(&zram->stats.good_compress); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 171 | |
| 172 | out: |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 173 | zram_stat64_sub(zram, &zram->stats.compr_size, clen); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 174 | zram_stat_dec(&zram->stats.pages_stored); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 175 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 176 | zram->table[index].page = NULL; |
| 177 | zram->table[index].offset = 0; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 178 | } |
| 179 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 180 | static void handle_zero_page(struct bio_vec *bvec) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 181 | { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 182 | struct page *page = bvec->bv_page; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 183 | void *user_mem; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 184 | |
| 185 | user_mem = kmap_atomic(page, KM_USER0); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 186 | memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 187 | kunmap_atomic(user_mem, KM_USER0); |
| 188 | |
Nitin Gupta | 30fb8a7 | 2009-12-12 11:44:46 +0530 | [diff] [blame] | 189 | flush_dcache_page(page); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 190 | } |
| 191 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 192 | static void handle_uncompressed_page(struct zram *zram, struct bio_vec *bvec, |
| 193 | u32 index, int offset) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 194 | { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 195 | struct page *page = bvec->bv_page; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 196 | unsigned char *user_mem, *cmem; |
| 197 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 198 | user_mem = kmap_atomic(page, KM_USER0); |
Jerome Marchand | 6a587e83 | 2011-06-10 15:28:46 +0200 | [diff] [blame] | 199 | cmem = kmap_atomic(zram->table[index].page, KM_USER1); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 200 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 201 | memcpy(user_mem + bvec->bv_offset, cmem + offset, bvec->bv_len); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 202 | kunmap_atomic(cmem, KM_USER1); |
Jerome Marchand | dffbb44 | 2011-07-13 17:20:05 +0200 | [diff] [blame] | 203 | kunmap_atomic(user_mem, KM_USER0); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 204 | |
Nitin Gupta | 30fb8a7 | 2009-12-12 11:44:46 +0530 | [diff] [blame] | 205 | flush_dcache_page(page); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 206 | } |
| 207 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 208 | static inline int is_partial_io(struct bio_vec *bvec) |
| 209 | { |
| 210 | return bvec->bv_len != PAGE_SIZE; |
| 211 | } |
| 212 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 213 | static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 214 | u32 index, int offset, struct bio *bio) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 215 | { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 216 | int ret; |
| 217 | size_t clen; |
| 218 | struct page *page; |
| 219 | struct zobj_header *zheader; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 220 | unsigned char *user_mem, *cmem, *uncmem = NULL; |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 221 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 222 | page = bvec->bv_page; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 223 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 224 | if (zram_test_flag(zram, index, ZRAM_ZERO)) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 225 | handle_zero_page(bvec); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 226 | return 0; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 227 | } |
| 228 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 229 | /* Requested page is not present in compressed area */ |
| 230 | if (unlikely(!zram->table[index].page)) { |
| 231 | pr_debug("Read before write: sector=%lu, size=%u", |
| 232 | (ulong)(bio->bi_sector), bio->bi_size); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 233 | handle_zero_page(bvec); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 234 | return 0; |
| 235 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 236 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 237 | /* Page is stored uncompressed since it's incompressible */ |
| 238 | if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 239 | handle_uncompressed_page(zram, bvec, index, offset); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 240 | return 0; |
| 241 | } |
| 242 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 243 | if (is_partial_io(bvec)) { |
| 244 | /* Use a temporary buffer to decompress the page */ |
| 245 | uncmem = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| 246 | if (!uncmem) { |
| 247 | pr_info("Error allocating temp memory!\n"); |
| 248 | return -ENOMEM; |
| 249 | } |
| 250 | } |
| 251 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 252 | user_mem = kmap_atomic(page, KM_USER0); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 253 | if (!is_partial_io(bvec)) |
| 254 | uncmem = user_mem; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 255 | clen = PAGE_SIZE; |
| 256 | |
| 257 | cmem = kmap_atomic(zram->table[index].page, KM_USER1) + |
| 258 | zram->table[index].offset; |
| 259 | |
| 260 | ret = lzo1x_decompress_safe(cmem + sizeof(*zheader), |
| 261 | xv_get_object_size(cmem) - sizeof(*zheader), |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 262 | uncmem, &clen); |
| 263 | |
| 264 | if (is_partial_io(bvec)) { |
| 265 | memcpy(user_mem + bvec->bv_offset, uncmem + offset, |
| 266 | bvec->bv_len); |
| 267 | kfree(uncmem); |
| 268 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 269 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 270 | kunmap_atomic(cmem, KM_USER1); |
Jerome Marchand | dffbb44 | 2011-07-13 17:20:05 +0200 | [diff] [blame] | 271 | kunmap_atomic(user_mem, KM_USER0); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 272 | |
| 273 | /* Should NEVER happen. Return bio error if it does. */ |
| 274 | if (unlikely(ret != LZO_E_OK)) { |
| 275 | pr_err("Decompression failed! err=%d, page=%u\n", ret, index); |
| 276 | zram_stat64_inc(zram, &zram->stats.failed_reads); |
| 277 | return ret; |
| 278 | } |
| 279 | |
| 280 | flush_dcache_page(page); |
| 281 | |
| 282 | return 0; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 283 | } |
| 284 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 285 | static int zram_read_before_write(struct zram *zram, char *mem, u32 index) |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 286 | { |
| 287 | int ret; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 288 | size_t clen = PAGE_SIZE; |
| 289 | struct zobj_header *zheader; |
| 290 | unsigned char *cmem; |
| 291 | |
| 292 | if (zram_test_flag(zram, index, ZRAM_ZERO) || |
| 293 | !zram->table[index].page) { |
| 294 | memset(mem, 0, PAGE_SIZE); |
| 295 | return 0; |
| 296 | } |
| 297 | |
| 298 | cmem = kmap_atomic(zram->table[index].page, KM_USER0) + |
| 299 | zram->table[index].offset; |
| 300 | |
| 301 | /* Page is stored uncompressed since it's incompressible */ |
| 302 | if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) { |
| 303 | memcpy(mem, cmem, PAGE_SIZE); |
| 304 | kunmap_atomic(cmem, KM_USER0); |
| 305 | return 0; |
| 306 | } |
| 307 | |
| 308 | ret = lzo1x_decompress_safe(cmem + sizeof(*zheader), |
| 309 | xv_get_object_size(cmem) - sizeof(*zheader), |
| 310 | mem, &clen); |
| 311 | kunmap_atomic(cmem, KM_USER0); |
| 312 | |
| 313 | /* Should NEVER happen. Return bio error if it does. */ |
| 314 | if (unlikely(ret != LZO_E_OK)) { |
| 315 | pr_err("Decompression failed! err=%d, page=%u\n", ret, index); |
| 316 | zram_stat64_inc(zram, &zram->stats.failed_reads); |
| 317 | return ret; |
| 318 | } |
| 319 | |
| 320 | return 0; |
| 321 | } |
| 322 | |
| 323 | static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, |
| 324 | int offset) |
| 325 | { |
| 326 | int ret; |
| 327 | u32 store_offset; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 328 | size_t clen; |
| 329 | struct zobj_header *zheader; |
| 330 | struct page *page, *page_store; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 331 | unsigned char *user_mem, *cmem, *src, *uncmem = NULL; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 332 | |
| 333 | page = bvec->bv_page; |
| 334 | src = zram->compress_buffer; |
| 335 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 336 | if (is_partial_io(bvec)) { |
| 337 | /* |
| 338 | * This is a partial IO. We need to read the full page |
| 339 | * before to write the changes. |
| 340 | */ |
| 341 | uncmem = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| 342 | if (!uncmem) { |
| 343 | pr_info("Error allocating temp memory!\n"); |
| 344 | ret = -ENOMEM; |
| 345 | goto out; |
| 346 | } |
| 347 | ret = zram_read_before_write(zram, uncmem, index); |
| 348 | if (ret) { |
| 349 | kfree(uncmem); |
| 350 | goto out; |
| 351 | } |
| 352 | } |
| 353 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 354 | /* |
| 355 | * System overwrites unused sectors. Free memory associated |
| 356 | * with this sector now. |
| 357 | */ |
| 358 | if (zram->table[index].page || |
| 359 | zram_test_flag(zram, index, ZRAM_ZERO)) |
| 360 | zram_free_page(zram, index); |
| 361 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 362 | user_mem = kmap_atomic(page, KM_USER0); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 363 | |
| 364 | if (is_partial_io(bvec)) |
| 365 | memcpy(uncmem + offset, user_mem + bvec->bv_offset, |
| 366 | bvec->bv_len); |
| 367 | else |
| 368 | uncmem = user_mem; |
| 369 | |
| 370 | if (page_zero_filled(uncmem)) { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 371 | kunmap_atomic(user_mem, KM_USER0); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 372 | if (is_partial_io(bvec)) |
| 373 | kfree(uncmem); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 374 | zram_stat_inc(&zram->stats.pages_zero); |
| 375 | zram_set_flag(zram, index, ZRAM_ZERO); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 376 | ret = 0; |
| 377 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 378 | } |
| 379 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 380 | ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen, |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 381 | zram->compress_workmem); |
| 382 | |
| 383 | kunmap_atomic(user_mem, KM_USER0); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 384 | if (is_partial_io(bvec)) |
| 385 | kfree(uncmem); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 386 | |
| 387 | if (unlikely(ret != LZO_E_OK)) { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 388 | pr_err("Compression failed! err=%d\n", ret); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 389 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 390 | } |
| 391 | |
| 392 | /* |
| 393 | * Page is incompressible. Store it as-is (uncompressed) |
| 394 | * since we do not want to return too many disk write |
| 395 | * errors which has side effect of hanging the system. |
| 396 | */ |
| 397 | if (unlikely(clen > max_zpage_size)) { |
| 398 | clen = PAGE_SIZE; |
| 399 | page_store = alloc_page(GFP_NOIO | __GFP_HIGHMEM); |
| 400 | if (unlikely(!page_store)) { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 401 | pr_info("Error allocating memory for " |
| 402 | "incompressible page: %u\n", index); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 403 | ret = -ENOMEM; |
| 404 | goto out; |
| 405 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 406 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 407 | store_offset = 0; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 408 | zram_set_flag(zram, index, ZRAM_UNCOMPRESSED); |
| 409 | zram_stat_inc(&zram->stats.pages_expand); |
| 410 | zram->table[index].page = page_store; |
| 411 | src = kmap_atomic(page, KM_USER0); |
| 412 | goto memstore; |
| 413 | } |
| 414 | |
| 415 | if (xv_malloc(zram->mem_pool, clen + sizeof(*zheader), |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 416 | &zram->table[index].page, &store_offset, |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 417 | GFP_NOIO | __GFP_HIGHMEM)) { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 418 | pr_info("Error allocating memory for compressed " |
| 419 | "page: %u, size=%zu\n", index, clen); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 420 | ret = -ENOMEM; |
| 421 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 422 | } |
| 423 | |
| 424 | memstore: |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 425 | zram->table[index].offset = store_offset; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 426 | |
| 427 | cmem = kmap_atomic(zram->table[index].page, KM_USER1) + |
| 428 | zram->table[index].offset; |
| 429 | |
| 430 | #if 0 |
| 431 | /* Back-reference needed for memory defragmentation */ |
| 432 | if (!zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)) { |
| 433 | zheader = (struct zobj_header *)cmem; |
| 434 | zheader->table_idx = index; |
| 435 | cmem += sizeof(*zheader); |
| 436 | } |
| 437 | #endif |
| 438 | |
| 439 | memcpy(cmem, src, clen); |
| 440 | |
| 441 | kunmap_atomic(cmem, KM_USER1); |
| 442 | if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) |
| 443 | kunmap_atomic(src, KM_USER0); |
| 444 | |
| 445 | /* Update stats */ |
| 446 | zram_stat64_add(zram, &zram->stats.compr_size, clen); |
| 447 | zram_stat_inc(&zram->stats.pages_stored); |
| 448 | if (clen <= PAGE_SIZE / 2) |
| 449 | zram_stat_inc(&zram->stats.good_compress); |
| 450 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 451 | return 0; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 452 | |
| 453 | out: |
| 454 | if (ret) |
| 455 | zram_stat64_inc(zram, &zram->stats.failed_writes); |
| 456 | return ret; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 457 | } |
| 458 | |
| 459 | static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 460 | int offset, struct bio *bio, int rw) |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 461 | { |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 462 | int ret; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 463 | |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 464 | if (rw == READ) { |
| 465 | down_read(&zram->lock); |
| 466 | ret = zram_bvec_read(zram, bvec, index, offset, bio); |
| 467 | up_read(&zram->lock); |
| 468 | } else { |
| 469 | down_write(&zram->lock); |
| 470 | ret = zram_bvec_write(zram, bvec, index, offset); |
| 471 | up_write(&zram->lock); |
| 472 | } |
| 473 | |
| 474 | return ret; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 475 | } |
| 476 | |
| 477 | static void update_position(u32 *index, int *offset, struct bio_vec *bvec) |
| 478 | { |
| 479 | if (*offset + bvec->bv_len >= PAGE_SIZE) |
| 480 | (*index)++; |
| 481 | *offset = (*offset + bvec->bv_len) % PAGE_SIZE; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 482 | } |
| 483 | |
| 484 | static void __zram_make_request(struct zram *zram, struct bio *bio, int rw) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 485 | { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 486 | int i, offset; |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 487 | u32 index; |
| 488 | struct bio_vec *bvec; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 489 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 490 | switch (rw) { |
| 491 | case READ: |
| 492 | zram_stat64_inc(zram, &zram->stats.num_reads); |
| 493 | break; |
| 494 | case WRITE: |
| 495 | zram_stat64_inc(zram, &zram->stats.num_writes); |
| 496 | break; |
| 497 | } |
| 498 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 499 | index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 500 | offset = (bio->bi_sector & (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 501 | |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 502 | bio_for_each_segment(bvec, bio, i) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 503 | int max_transfer_size = PAGE_SIZE - offset; |
| 504 | |
| 505 | if (bvec->bv_len > max_transfer_size) { |
| 506 | /* |
| 507 | * zram_bvec_rw() can only make operation on a single |
| 508 | * zram page. Split the bio vector. |
| 509 | */ |
| 510 | struct bio_vec bv; |
| 511 | |
| 512 | bv.bv_page = bvec->bv_page; |
| 513 | bv.bv_len = max_transfer_size; |
| 514 | bv.bv_offset = bvec->bv_offset; |
| 515 | |
| 516 | if (zram_bvec_rw(zram, &bv, index, offset, bio, rw) < 0) |
| 517 | goto out; |
| 518 | |
| 519 | bv.bv_len = bvec->bv_len - max_transfer_size; |
| 520 | bv.bv_offset += max_transfer_size; |
| 521 | if (zram_bvec_rw(zram, &bv, index+1, 0, bio, rw) < 0) |
| 522 | goto out; |
| 523 | } else |
| 524 | if (zram_bvec_rw(zram, bvec, index, offset, bio, rw) |
| 525 | < 0) |
| 526 | goto out; |
| 527 | |
| 528 | update_position(&index, &offset, bvec); |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 529 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 530 | |
| 531 | set_bit(BIO_UPTODATE, &bio->bi_flags); |
| 532 | bio_endio(bio, 0); |
Nitin Gupta | 7d7854b | 2011-01-22 07:36:15 -0500 | [diff] [blame] | 533 | return; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 534 | |
| 535 | out: |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 536 | bio_io_error(bio); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 537 | } |
| 538 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 539 | /* |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 540 | * Check if request is within bounds and aligned on zram logical blocks. |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 541 | */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 542 | static inline int valid_io_request(struct zram *zram, struct bio *bio) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 543 | { |
| 544 | if (unlikely( |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 545 | (bio->bi_sector >= (zram->disksize >> SECTOR_SHIFT)) || |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 546 | (bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)) || |
| 547 | (bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 548 | |
| 549 | return 0; |
| 550 | } |
| 551 | |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 552 | /* I/O request is valid */ |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 553 | return 1; |
| 554 | } |
| 555 | |
| 556 | /* |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 557 | * Handler function for all zram I/O requests. |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 558 | */ |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 559 | static void zram_make_request(struct request_queue *queue, struct bio *bio) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 560 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 561 | struct zram *zram = queue->queuedata; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 562 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 563 | if (unlikely(!zram->init_done) && zram_init_device(zram)) |
| 564 | goto error; |
| 565 | |
| 566 | down_read(&zram->init_lock); |
| 567 | if (unlikely(!zram->init_done)) |
| 568 | goto error_unlock; |
| 569 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 570 | if (!valid_io_request(zram, bio)) { |
| 571 | zram_stat64_inc(zram, &zram->stats.invalid_io); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 572 | goto error_unlock; |
Jerome Marchand | 6642a67 | 2011-02-17 17:11:49 +0100 | [diff] [blame] | 573 | } |
| 574 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 575 | __zram_make_request(zram, bio, bio_data_dir(bio)); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 576 | up_read(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 577 | |
Linus Torvalds | b4fdcb0 | 2011-11-04 17:06:58 -0700 | [diff] [blame^] | 578 | return; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 579 | |
| 580 | error_unlock: |
| 581 | up_read(&zram->init_lock); |
| 582 | error: |
| 583 | bio_io_error(bio); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 584 | } |
| 585 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 586 | void __zram_reset_device(struct zram *zram) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 587 | { |
Nitin Gupta | 97a0638 | 2010-05-13 14:24:21 +0530 | [diff] [blame] | 588 | size_t index; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 589 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 590 | zram->init_done = 0; |
Nitin Gupta | 7eef753 | 2010-01-28 21:13:38 +0530 | [diff] [blame] | 591 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 592 | /* Free various per-device buffers */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 593 | kfree(zram->compress_workmem); |
| 594 | free_pages((unsigned long)zram->compress_buffer, 1); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 595 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 596 | zram->compress_workmem = NULL; |
| 597 | zram->compress_buffer = NULL; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 598 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 599 | /* Free all pages that are still in this zram device */ |
| 600 | for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 601 | struct page *page; |
| 602 | u16 offset; |
| 603 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 604 | page = zram->table[index].page; |
| 605 | offset = zram->table[index].offset; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 606 | |
| 607 | if (!page) |
| 608 | continue; |
| 609 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 610 | if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 611 | __free_page(page); |
| 612 | else |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 613 | xv_free(zram->mem_pool, page, offset); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 614 | } |
| 615 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 616 | vfree(zram->table); |
| 617 | zram->table = NULL; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 618 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 619 | xv_destroy_pool(zram->mem_pool); |
| 620 | zram->mem_pool = NULL; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 621 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 622 | /* Reset stats */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 623 | memset(&zram->stats, 0, sizeof(zram->stats)); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 624 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 625 | zram->disksize = 0; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 626 | } |
| 627 | |
| 628 | void zram_reset_device(struct zram *zram) |
| 629 | { |
| 630 | down_write(&zram->init_lock); |
| 631 | __zram_reset_device(zram); |
| 632 | up_write(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 633 | } |
| 634 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 635 | int zram_init_device(struct zram *zram) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 636 | { |
| 637 | int ret; |
| 638 | size_t num_pages; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 639 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 640 | down_write(&zram->init_lock); |
Nitin Gupta | 484875a | 2010-08-09 22:56:48 +0530 | [diff] [blame] | 641 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 642 | if (zram->init_done) { |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 643 | up_write(&zram->init_lock); |
Nitin Gupta | 484875a | 2010-08-09 22:56:48 +0530 | [diff] [blame] | 644 | return 0; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 645 | } |
| 646 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 647 | zram_set_disksize(zram, totalram_pages << PAGE_SHIFT); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 648 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 649 | zram->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); |
| 650 | if (!zram->compress_workmem) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 651 | pr_err("Error allocating compressor working memory!\n"); |
| 652 | ret = -ENOMEM; |
Jerome Marchand | 5a18c53 | 2011-09-06 15:02:12 +0200 | [diff] [blame] | 653 | goto fail_no_table; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 654 | } |
| 655 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 656 | zram->compress_buffer = (void *)__get_free_pages(__GFP_ZERO, 1); |
| 657 | if (!zram->compress_buffer) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 658 | pr_err("Error allocating compressor buffer space\n"); |
| 659 | ret = -ENOMEM; |
Jerome Marchand | 5a18c53 | 2011-09-06 15:02:12 +0200 | [diff] [blame] | 660 | goto fail_no_table; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 661 | } |
| 662 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 663 | num_pages = zram->disksize >> PAGE_SHIFT; |
Joe Perches | 5b84cc7 | 2010-11-04 20:07:59 -0700 | [diff] [blame] | 664 | zram->table = vzalloc(num_pages * sizeof(*zram->table)); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 665 | if (!zram->table) { |
| 666 | pr_err("Error allocating zram address table\n"); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 667 | ret = -ENOMEM; |
Jerome Marchand | 5a18c53 | 2011-09-06 15:02:12 +0200 | [diff] [blame] | 668 | goto fail_no_table; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 669 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 670 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 671 | set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 672 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 673 | /* zram devices sort of resembles non-rotational disks */ |
| 674 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 675 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 676 | zram->mem_pool = xv_create_pool(); |
| 677 | if (!zram->mem_pool) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 678 | pr_err("Error creating memory pool\n"); |
| 679 | ret = -ENOMEM; |
| 680 | goto fail; |
| 681 | } |
| 682 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 683 | zram->init_done = 1; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 684 | up_write(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 685 | |
| 686 | pr_debug("Initialization done!\n"); |
| 687 | return 0; |
| 688 | |
Jerome Marchand | 5a18c53 | 2011-09-06 15:02:12 +0200 | [diff] [blame] | 689 | fail_no_table: |
| 690 | /* To prevent accessing table entries during cleanup */ |
| 691 | zram->disksize = 0; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 692 | fail: |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 693 | __zram_reset_device(zram); |
| 694 | up_write(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 695 | pr_err("Initialization failed: err=%d\n", ret); |
| 696 | return ret; |
| 697 | } |
| 698 | |
Nitin Gupta | 2ccbec0 | 2011-09-09 19:01:00 -0400 | [diff] [blame] | 699 | static void zram_slot_free_notify(struct block_device *bdev, |
| 700 | unsigned long index) |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 701 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 702 | struct zram *zram; |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 703 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 704 | zram = bdev->bd_disk->private_data; |
| 705 | zram_free_page(zram, index); |
| 706 | zram_stat64_inc(zram, &zram->stats.notify_free); |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 707 | } |
| 708 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 709 | static const struct block_device_operations zram_devops = { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 710 | .swap_slot_free_notify = zram_slot_free_notify, |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 711 | .owner = THIS_MODULE |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 712 | }; |
| 713 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 714 | static int create_device(struct zram *zram, int device_id) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 715 | { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 716 | int ret = 0; |
| 717 | |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 718 | init_rwsem(&zram->lock); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 719 | init_rwsem(&zram->init_lock); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 720 | spin_lock_init(&zram->stat64_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 721 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 722 | zram->queue = blk_alloc_queue(GFP_KERNEL); |
| 723 | if (!zram->queue) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 724 | pr_err("Error allocating disk queue for device %d\n", |
| 725 | device_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 726 | ret = -ENOMEM; |
| 727 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 728 | } |
| 729 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 730 | blk_queue_make_request(zram->queue, zram_make_request); |
| 731 | zram->queue->queuedata = zram; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 732 | |
| 733 | /* gendisk structure */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 734 | zram->disk = alloc_disk(1); |
| 735 | if (!zram->disk) { |
| 736 | blk_cleanup_queue(zram->queue); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 737 | pr_warning("Error allocating disk structure for device %d\n", |
| 738 | device_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 739 | ret = -ENOMEM; |
| 740 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 741 | } |
| 742 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 743 | zram->disk->major = zram_major; |
| 744 | zram->disk->first_minor = device_id; |
| 745 | zram->disk->fops = &zram_devops; |
| 746 | zram->disk->queue = zram->queue; |
| 747 | zram->disk->private_data = zram; |
| 748 | snprintf(zram->disk->disk_name, 16, "zram%d", device_id); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 749 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 750 | /* Actual capacity set using syfs (/sys/block/zram<id>/disksize */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 751 | set_capacity(zram->disk, 0); |
Nitin Gupta | 5d83d5a | 2010-01-28 21:13:39 +0530 | [diff] [blame] | 752 | |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 753 | /* |
| 754 | * To ensure that we always get PAGE_SIZE aligned |
| 755 | * and n*PAGE_SIZED sized I/O requests. |
| 756 | */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 757 | blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE); |
Robert Jennings | 7b19b8d | 2011-01-28 08:58:17 -0600 | [diff] [blame] | 758 | blk_queue_logical_block_size(zram->disk->queue, |
| 759 | ZRAM_LOGICAL_BLOCK_SIZE); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 760 | blk_queue_io_min(zram->disk->queue, PAGE_SIZE); |
| 761 | blk_queue_io_opt(zram->disk->queue, PAGE_SIZE); |
Nitin Gupta | 5d83d5a | 2010-01-28 21:13:39 +0530 | [diff] [blame] | 762 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 763 | add_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 764 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 765 | ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj, |
| 766 | &zram_disk_attr_group); |
| 767 | if (ret < 0) { |
| 768 | pr_warning("Error creating sysfs group"); |
| 769 | goto out; |
| 770 | } |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 771 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 772 | zram->init_done = 0; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 773 | |
| 774 | out: |
| 775 | return ret; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 776 | } |
| 777 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 778 | static void destroy_device(struct zram *zram) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 779 | { |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 780 | sysfs_remove_group(&disk_to_dev(zram->disk)->kobj, |
| 781 | &zram_disk_attr_group); |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 782 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 783 | if (zram->disk) { |
| 784 | del_gendisk(zram->disk); |
| 785 | put_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 786 | } |
| 787 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 788 | if (zram->queue) |
| 789 | blk_cleanup_queue(zram->queue); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 790 | } |
| 791 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 792 | static int __init zram_init(void) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 793 | { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 794 | int ret, dev_id; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 795 | |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 796 | if (zram_num_devices > max_num_devices) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 797 | pr_warning("Invalid value for num_devices: %u\n", |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 798 | zram_num_devices); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 799 | ret = -EINVAL; |
| 800 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 801 | } |
| 802 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 803 | zram_major = register_blkdev(0, "zram"); |
| 804 | if (zram_major <= 0) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 805 | pr_warning("Unable to get major number\n"); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 806 | ret = -EBUSY; |
| 807 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 808 | } |
| 809 | |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 810 | if (!zram_num_devices) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 811 | pr_info("num_devices not specified. Using default: 1\n"); |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 812 | zram_num_devices = 1; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 813 | } |
| 814 | |
| 815 | /* Allocate the device array and initialize each one */ |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 816 | pr_info("Creating %u devices ...\n", zram_num_devices); |
| 817 | zram_devices = kzalloc(zram_num_devices * sizeof(struct zram), GFP_KERNEL); |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 818 | if (!zram_devices) { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 819 | ret = -ENOMEM; |
| 820 | goto unregister; |
| 821 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 822 | |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 823 | for (dev_id = 0; dev_id < zram_num_devices; dev_id++) { |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 824 | ret = create_device(&zram_devices[dev_id], dev_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 825 | if (ret) |
Minchan Kim | 3bf040c | 2010-01-11 16:15:53 +0900 | [diff] [blame] | 826 | goto free_devices; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 827 | } |
| 828 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 829 | return 0; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 830 | |
Minchan Kim | 3bf040c | 2010-01-11 16:15:53 +0900 | [diff] [blame] | 831 | free_devices: |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 832 | while (dev_id) |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 833 | destroy_device(&zram_devices[--dev_id]); |
| 834 | kfree(zram_devices); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 835 | unregister: |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 836 | unregister_blkdev(zram_major, "zram"); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 837 | out: |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 838 | return ret; |
| 839 | } |
| 840 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 841 | static void __exit zram_exit(void) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 842 | { |
| 843 | int i; |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 844 | struct zram *zram; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 845 | |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 846 | for (i = 0; i < zram_num_devices; i++) { |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 847 | zram = &zram_devices[i]; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 848 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 849 | destroy_device(zram); |
| 850 | if (zram->init_done) |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 851 | zram_reset_device(zram); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 852 | } |
| 853 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 854 | unregister_blkdev(zram_major, "zram"); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 855 | |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 856 | kfree(zram_devices); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 857 | pr_debug("Cleanup done!\n"); |
| 858 | } |
| 859 | |
Noah Watkins | efd54f4 | 2011-07-20 17:06:08 -0600 | [diff] [blame] | 860 | module_param(zram_num_devices, uint, 0); |
| 861 | MODULE_PARM_DESC(zram_num_devices, "Number of zram devices"); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 862 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 863 | module_init(zram_init); |
| 864 | module_exit(zram_exit); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 865 | |
| 866 | MODULE_LICENSE("Dual BSD/GPL"); |
| 867 | MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>"); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 868 | MODULE_DESCRIPTION("Compressed RAM Block Device"); |