Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1 | /* |
| 2 | * zsmalloc memory allocator |
| 3 | * |
| 4 | * Copyright (C) 2011 Nitin Gupta |
Minchan Kim | 31fc00b | 2014-01-30 15:45:55 -0800 | [diff] [blame] | 5 | * Copyright (C) 2012, 2013 Minchan Kim |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 6 | * |
| 7 | * This code is released using a dual license strategy: BSD/GPL |
| 8 | * You can choose the license 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 | */ |
| 13 | |
Nitin Gupta | 2db51da | 2012-06-09 17:41:14 -0700 | [diff] [blame] | 14 | /* |
Nitin Gupta | 2db51da | 2012-06-09 17:41:14 -0700 | [diff] [blame] | 15 | * Following is how we use various fields and flags of underlying |
| 16 | * struct page(s) to form a zspage. |
| 17 | * |
| 18 | * Usage of struct page fields: |
| 19 | * page->first_page: points to the first component (0-order) page |
| 20 | * page->index (union with page->freelist): offset of the first object |
| 21 | * starting in this page. For the first page, this is |
| 22 | * always 0, so we use this field (aka freelist) to point |
| 23 | * to the first free object in zspage. |
| 24 | * page->lru: links together all component pages (except the first page) |
| 25 | * of a zspage |
| 26 | * |
| 27 | * For _first_ page only: |
| 28 | * |
| 29 | * page->private (union with page->first_page): refers to the |
| 30 | * component page after the first page |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 31 | * If the page is first_page for huge object, it stores handle. |
| 32 | * Look at size_class->huge. |
Nitin Gupta | 2db51da | 2012-06-09 17:41:14 -0700 | [diff] [blame] | 33 | * page->freelist: points to the first free object in zspage. |
| 34 | * Free objects are linked together using in-place |
| 35 | * metadata. |
| 36 | * page->objects: maximum number of objects we can store in this |
| 37 | * zspage (class->zspage_order * PAGE_SIZE / class->size) |
| 38 | * page->lru: links together first pages of various zspages. |
| 39 | * Basically forming list of zspages in a fullness group. |
| 40 | * page->mapping: class index and fullness group of the zspage |
| 41 | * |
| 42 | * Usage of struct page flags: |
| 43 | * PG_private: identifies the first component page |
| 44 | * PG_private2: identifies the last component page |
| 45 | * |
| 46 | */ |
| 47 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 48 | #ifdef CONFIG_ZSMALLOC_DEBUG |
| 49 | #define DEBUG |
| 50 | #endif |
| 51 | |
| 52 | #include <linux/module.h> |
| 53 | #include <linux/kernel.h> |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 54 | #include <linux/sched.h> |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 55 | #include <linux/bitops.h> |
| 56 | #include <linux/errno.h> |
| 57 | #include <linux/highmem.h> |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 58 | #include <linux/string.h> |
| 59 | #include <linux/slab.h> |
| 60 | #include <asm/tlbflush.h> |
| 61 | #include <asm/pgtable.h> |
| 62 | #include <linux/cpumask.h> |
| 63 | #include <linux/cpu.h> |
Seth Jennings | 0cbb613 | 2012-02-13 08:47:49 -0600 | [diff] [blame] | 64 | #include <linux/vmalloc.h> |
Seth Jennings | c60369f | 2012-07-18 11:55:55 -0500 | [diff] [blame] | 65 | #include <linux/hardirq.h> |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 66 | #include <linux/spinlock.h> |
| 67 | #include <linux/types.h> |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 68 | #include <linux/debugfs.h> |
Minchan Kim | bcf1647 | 2014-01-30 15:45:50 -0800 | [diff] [blame] | 69 | #include <linux/zsmalloc.h> |
Dan Streetman | c795779 | 2014-08-06 16:08:38 -0700 | [diff] [blame] | 70 | #include <linux/zpool.h> |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 71 | |
| 72 | /* |
| 73 | * This must be power of 2 and greater than of equal to sizeof(link_free). |
| 74 | * These two conditions ensure that any 'struct link_free' itself doesn't |
| 75 | * span more than 1 page which avoids complex case of mapping 2 pages simply |
| 76 | * to restore link_free pointer values. |
| 77 | */ |
| 78 | #define ZS_ALIGN 8 |
| 79 | |
| 80 | /* |
| 81 | * A single 'zspage' is composed of up to 2^N discontiguous 0-order (single) |
| 82 | * pages. ZS_MAX_ZSPAGE_ORDER defines upper limit on N. |
| 83 | */ |
| 84 | #define ZS_MAX_ZSPAGE_ORDER 2 |
| 85 | #define ZS_MAX_PAGES_PER_ZSPAGE (_AC(1, UL) << ZS_MAX_ZSPAGE_ORDER) |
| 86 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 87 | #define ZS_HANDLE_SIZE (sizeof(unsigned long)) |
| 88 | |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 89 | /* |
| 90 | * Object location (<PFN>, <obj_idx>) is encoded as |
Nitin Cupta | c3e3e88a | 2013-12-11 11:04:37 +0900 | [diff] [blame] | 91 | * as single (unsigned long) handle value. |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 92 | * |
| 93 | * Note that object index <obj_idx> is relative to system |
| 94 | * page <PFN> it is stored in, so for each sub-page belonging |
| 95 | * to a zspage, obj_idx starts with 0. |
| 96 | * |
| 97 | * This is made more complicated by various memory models and PAE. |
| 98 | */ |
| 99 | |
| 100 | #ifndef MAX_PHYSMEM_BITS |
| 101 | #ifdef CONFIG_HIGHMEM64G |
| 102 | #define MAX_PHYSMEM_BITS 36 |
| 103 | #else /* !CONFIG_HIGHMEM64G */ |
| 104 | /* |
| 105 | * If this definition of MAX_PHYSMEM_BITS is used, OBJ_INDEX_BITS will just |
| 106 | * be PAGE_SHIFT |
| 107 | */ |
| 108 | #define MAX_PHYSMEM_BITS BITS_PER_LONG |
| 109 | #endif |
| 110 | #endif |
| 111 | #define _PFN_BITS (MAX_PHYSMEM_BITS - PAGE_SHIFT) |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 112 | |
| 113 | /* |
| 114 | * Memory for allocating for handle keeps object position by |
| 115 | * encoding <page, obj_idx> and the encoded value has a room |
| 116 | * in least bit(ie, look at obj_to_location). |
| 117 | * We use the bit to synchronize between object access by |
| 118 | * user and migration. |
| 119 | */ |
| 120 | #define HANDLE_PIN_BIT 0 |
| 121 | |
| 122 | /* |
| 123 | * Head in allocated object should have OBJ_ALLOCATED_TAG |
| 124 | * to identify the object was allocated or not. |
| 125 | * It's okay to add the status bit in the least bit because |
| 126 | * header keeps handle which is 4byte-aligned address so we |
| 127 | * have room for two bit at least. |
| 128 | */ |
| 129 | #define OBJ_ALLOCATED_TAG 1 |
| 130 | #define OBJ_TAG_BITS 1 |
| 131 | #define OBJ_INDEX_BITS (BITS_PER_LONG - _PFN_BITS - OBJ_TAG_BITS) |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 132 | #define OBJ_INDEX_MASK ((_AC(1, UL) << OBJ_INDEX_BITS) - 1) |
| 133 | |
| 134 | #define MAX(a, b) ((a) >= (b) ? (a) : (b)) |
| 135 | /* ZS_MIN_ALLOC_SIZE must be multiple of ZS_ALIGN */ |
| 136 | #define ZS_MIN_ALLOC_SIZE \ |
| 137 | MAX(32, (ZS_MAX_PAGES_PER_ZSPAGE << PAGE_SHIFT >> OBJ_INDEX_BITS)) |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 138 | /* each chunk includes extra space to keep handle */ |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 139 | #define ZS_MAX_ALLOC_SIZE PAGE_SIZE |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 140 | |
| 141 | /* |
Weijie Yang | 7eb5251 | 2014-06-04 16:11:08 -0700 | [diff] [blame] | 142 | * On systems with 4K page size, this gives 255 size classes! There is a |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 143 | * trader-off here: |
| 144 | * - Large number of size classes is potentially wasteful as free page are |
| 145 | * spread across these classes |
| 146 | * - Small number of size classes causes large internal fragmentation |
| 147 | * - Probably its better to use specific size classes (empirically |
| 148 | * determined). NOTE: all those class sizes must be set as multiple of |
| 149 | * ZS_ALIGN to make sure link_free itself never has to span 2 pages. |
| 150 | * |
| 151 | * ZS_MIN_ALLOC_SIZE and ZS_SIZE_CLASS_DELTA must be multiple of ZS_ALIGN |
| 152 | * (reason above) |
| 153 | */ |
Seth Jennings | d662b8e | 2013-01-25 11:46:18 -0600 | [diff] [blame] | 154 | #define ZS_SIZE_CLASS_DELTA (PAGE_SIZE >> 8) |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 155 | |
| 156 | /* |
| 157 | * We do not maintain any list for completely empty or full pages |
| 158 | */ |
| 159 | enum fullness_group { |
| 160 | ZS_ALMOST_FULL, |
| 161 | ZS_ALMOST_EMPTY, |
| 162 | _ZS_NR_FULLNESS_GROUPS, |
| 163 | |
| 164 | ZS_EMPTY, |
| 165 | ZS_FULL |
| 166 | }; |
| 167 | |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 168 | enum zs_stat_type { |
| 169 | OBJ_ALLOCATED, |
| 170 | OBJ_USED, |
Minchan Kim | 248ca1b | 2015-04-15 16:15:42 -0700 | [diff] [blame] | 171 | CLASS_ALMOST_FULL, |
| 172 | CLASS_ALMOST_EMPTY, |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 173 | NR_ZS_STAT_TYPE, |
| 174 | }; |
| 175 | |
| 176 | #ifdef CONFIG_ZSMALLOC_STAT |
| 177 | |
| 178 | static struct dentry *zs_stat_root; |
| 179 | |
| 180 | struct zs_size_stat { |
| 181 | unsigned long objs[NR_ZS_STAT_TYPE]; |
| 182 | }; |
| 183 | |
| 184 | #endif |
| 185 | |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 186 | /* |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 187 | * number of size_classes |
| 188 | */ |
| 189 | static int zs_size_classes; |
| 190 | |
| 191 | /* |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 192 | * We assign a page to ZS_ALMOST_EMPTY fullness group when: |
| 193 | * n <= N / f, where |
| 194 | * n = number of allocated objects |
| 195 | * N = total number of objects zspage can store |
Wang Sheng-Hui | 6dd9737 | 2014-10-09 15:29:59 -0700 | [diff] [blame] | 196 | * f = fullness_threshold_frac |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 197 | * |
| 198 | * Similarly, we assign zspage to: |
| 199 | * ZS_ALMOST_FULL when n > N / f |
| 200 | * ZS_EMPTY when n == 0 |
| 201 | * ZS_FULL when n == N |
| 202 | * |
| 203 | * (see: fix_fullness_group()) |
| 204 | */ |
| 205 | static const int fullness_threshold_frac = 4; |
| 206 | |
| 207 | struct size_class { |
| 208 | /* |
| 209 | * Size of objects stored in this class. Must be multiple |
| 210 | * of ZS_ALIGN. |
| 211 | */ |
| 212 | int size; |
| 213 | unsigned int index; |
| 214 | |
| 215 | /* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */ |
| 216 | int pages_per_zspage; |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 217 | /* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */ |
| 218 | bool huge; |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 219 | |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 220 | #ifdef CONFIG_ZSMALLOC_STAT |
| 221 | struct zs_size_stat stats; |
| 222 | #endif |
| 223 | |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 224 | spinlock_t lock; |
| 225 | |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 226 | struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS]; |
| 227 | }; |
| 228 | |
| 229 | /* |
| 230 | * Placed within free objects to form a singly linked list. |
| 231 | * For every zspage, first_page->freelist gives head of this list. |
| 232 | * |
| 233 | * This must be power of 2 and less than or equal to ZS_ALIGN |
| 234 | */ |
| 235 | struct link_free { |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 236 | union { |
| 237 | /* |
| 238 | * Position of next free chunk (encodes <PFN, obj_idx>) |
| 239 | * It's valid for non-allocated object |
| 240 | */ |
| 241 | void *next; |
| 242 | /* |
| 243 | * Handle of allocated object. |
| 244 | */ |
| 245 | unsigned long handle; |
| 246 | }; |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 247 | }; |
| 248 | |
| 249 | struct zs_pool { |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 250 | char *name; |
| 251 | |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 252 | struct size_class **size_class; |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 253 | struct kmem_cache *handle_cachep; |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 254 | |
| 255 | gfp_t flags; /* allocation flags used when growing pool */ |
Minchan Kim | 13de893 | 2014-10-09 15:29:48 -0700 | [diff] [blame] | 256 | atomic_long_t pages_allocated; |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 257 | |
| 258 | #ifdef CONFIG_ZSMALLOC_STAT |
| 259 | struct dentry *stat_dentry; |
| 260 | #endif |
Seth Jennings | 0959c63 | 2012-08-08 15:12:17 +0900 | [diff] [blame] | 261 | }; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 262 | |
| 263 | /* |
| 264 | * A zspage's class index and fullness group |
| 265 | * are encoded in its (first)page->mapping |
| 266 | */ |
| 267 | #define CLASS_IDX_BITS 28 |
| 268 | #define FULLNESS_BITS 4 |
| 269 | #define CLASS_IDX_MASK ((1 << CLASS_IDX_BITS) - 1) |
| 270 | #define FULLNESS_MASK ((1 << FULLNESS_BITS) - 1) |
| 271 | |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 272 | struct mapping_area { |
Minchan Kim | 1b945ae | 2013-12-11 11:04:36 +0900 | [diff] [blame] | 273 | #ifdef CONFIG_PGTABLE_MAPPING |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 274 | struct vm_struct *vm; /* vm area for mapping object that span pages */ |
| 275 | #else |
| 276 | char *vm_buf; /* copy buffer for objects that span pages */ |
| 277 | #endif |
| 278 | char *vm_addr; /* address of kmap_atomic()'ed pages */ |
| 279 | enum zs_mapmode vm_mm; /* mapping mode */ |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 280 | bool huge; |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 281 | }; |
| 282 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 283 | static int create_handle_cache(struct zs_pool *pool) |
| 284 | { |
| 285 | pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_SIZE, |
| 286 | 0, 0, NULL); |
| 287 | return pool->handle_cachep ? 0 : 1; |
| 288 | } |
| 289 | |
| 290 | static void destroy_handle_cache(struct zs_pool *pool) |
| 291 | { |
Sergey Senozhatsky | 02f7b41 | 2015-06-10 11:14:57 -0700 | [diff] [blame] | 292 | if (pool->handle_cachep) |
| 293 | kmem_cache_destroy(pool->handle_cachep); |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 294 | } |
| 295 | |
| 296 | static unsigned long alloc_handle(struct zs_pool *pool) |
| 297 | { |
| 298 | return (unsigned long)kmem_cache_alloc(pool->handle_cachep, |
| 299 | pool->flags & ~__GFP_HIGHMEM); |
| 300 | } |
| 301 | |
| 302 | static void free_handle(struct zs_pool *pool, unsigned long handle) |
| 303 | { |
| 304 | kmem_cache_free(pool->handle_cachep, (void *)handle); |
| 305 | } |
| 306 | |
| 307 | static void record_obj(unsigned long handle, unsigned long obj) |
| 308 | { |
| 309 | *(unsigned long *)handle = obj; |
| 310 | } |
| 311 | |
Dan Streetman | c795779 | 2014-08-06 16:08:38 -0700 | [diff] [blame] | 312 | /* zpool driver */ |
| 313 | |
| 314 | #ifdef CONFIG_ZPOOL |
| 315 | |
Ganesh Mahendran | 3eba0c6 | 2015-02-12 15:00:51 -0800 | [diff] [blame] | 316 | static void *zs_zpool_create(char *name, gfp_t gfp, struct zpool_ops *zpool_ops) |
Dan Streetman | c795779 | 2014-08-06 16:08:38 -0700 | [diff] [blame] | 317 | { |
Ganesh Mahendran | 3eba0c6 | 2015-02-12 15:00:51 -0800 | [diff] [blame] | 318 | return zs_create_pool(name, gfp); |
Dan Streetman | c795779 | 2014-08-06 16:08:38 -0700 | [diff] [blame] | 319 | } |
| 320 | |
| 321 | static void zs_zpool_destroy(void *pool) |
| 322 | { |
| 323 | zs_destroy_pool(pool); |
| 324 | } |
| 325 | |
| 326 | static int zs_zpool_malloc(void *pool, size_t size, gfp_t gfp, |
| 327 | unsigned long *handle) |
| 328 | { |
| 329 | *handle = zs_malloc(pool, size); |
| 330 | return *handle ? 0 : -1; |
| 331 | } |
| 332 | static void zs_zpool_free(void *pool, unsigned long handle) |
| 333 | { |
| 334 | zs_free(pool, handle); |
| 335 | } |
| 336 | |
| 337 | static int zs_zpool_shrink(void *pool, unsigned int pages, |
| 338 | unsigned int *reclaimed) |
| 339 | { |
| 340 | return -EINVAL; |
| 341 | } |
| 342 | |
| 343 | static void *zs_zpool_map(void *pool, unsigned long handle, |
| 344 | enum zpool_mapmode mm) |
| 345 | { |
| 346 | enum zs_mapmode zs_mm; |
| 347 | |
| 348 | switch (mm) { |
| 349 | case ZPOOL_MM_RO: |
| 350 | zs_mm = ZS_MM_RO; |
| 351 | break; |
| 352 | case ZPOOL_MM_WO: |
| 353 | zs_mm = ZS_MM_WO; |
| 354 | break; |
| 355 | case ZPOOL_MM_RW: /* fallthru */ |
| 356 | default: |
| 357 | zs_mm = ZS_MM_RW; |
| 358 | break; |
| 359 | } |
| 360 | |
| 361 | return zs_map_object(pool, handle, zs_mm); |
| 362 | } |
| 363 | static void zs_zpool_unmap(void *pool, unsigned long handle) |
| 364 | { |
| 365 | zs_unmap_object(pool, handle); |
| 366 | } |
| 367 | |
| 368 | static u64 zs_zpool_total_size(void *pool) |
| 369 | { |
Minchan Kim | 722cdc1 | 2014-10-09 15:29:50 -0700 | [diff] [blame] | 370 | return zs_get_total_pages(pool) << PAGE_SHIFT; |
Dan Streetman | c795779 | 2014-08-06 16:08:38 -0700 | [diff] [blame] | 371 | } |
| 372 | |
| 373 | static struct zpool_driver zs_zpool_driver = { |
| 374 | .type = "zsmalloc", |
| 375 | .owner = THIS_MODULE, |
| 376 | .create = zs_zpool_create, |
| 377 | .destroy = zs_zpool_destroy, |
| 378 | .malloc = zs_zpool_malloc, |
| 379 | .free = zs_zpool_free, |
| 380 | .shrink = zs_zpool_shrink, |
| 381 | .map = zs_zpool_map, |
| 382 | .unmap = zs_zpool_unmap, |
| 383 | .total_size = zs_zpool_total_size, |
| 384 | }; |
| 385 | |
Kees Cook | 137f8cf | 2014-08-29 15:18:40 -0700 | [diff] [blame] | 386 | MODULE_ALIAS("zpool-zsmalloc"); |
Dan Streetman | c795779 | 2014-08-06 16:08:38 -0700 | [diff] [blame] | 387 | #endif /* CONFIG_ZPOOL */ |
| 388 | |
Minchan Kim | 248ca1b | 2015-04-15 16:15:42 -0700 | [diff] [blame] | 389 | static unsigned int get_maxobj_per_zspage(int size, int pages_per_zspage) |
| 390 | { |
| 391 | return pages_per_zspage * PAGE_SIZE / size; |
| 392 | } |
| 393 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 394 | /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */ |
| 395 | static DEFINE_PER_CPU(struct mapping_area, zs_map_area); |
| 396 | |
| 397 | static int is_first_page(struct page *page) |
| 398 | { |
Minchan Kim | a27545bf | 2012-04-25 15:23:09 +0900 | [diff] [blame] | 399 | return PagePrivate(page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 400 | } |
| 401 | |
| 402 | static int is_last_page(struct page *page) |
| 403 | { |
Minchan Kim | a27545bf | 2012-04-25 15:23:09 +0900 | [diff] [blame] | 404 | return PagePrivate2(page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 405 | } |
| 406 | |
| 407 | static void get_zspage_mapping(struct page *page, unsigned int *class_idx, |
| 408 | enum fullness_group *fullness) |
| 409 | { |
| 410 | unsigned long m; |
| 411 | BUG_ON(!is_first_page(page)); |
| 412 | |
| 413 | m = (unsigned long)page->mapping; |
| 414 | *fullness = m & FULLNESS_MASK; |
| 415 | *class_idx = (m >> FULLNESS_BITS) & CLASS_IDX_MASK; |
| 416 | } |
| 417 | |
| 418 | static void set_zspage_mapping(struct page *page, unsigned int class_idx, |
| 419 | enum fullness_group fullness) |
| 420 | { |
| 421 | unsigned long m; |
| 422 | BUG_ON(!is_first_page(page)); |
| 423 | |
| 424 | m = ((class_idx & CLASS_IDX_MASK) << FULLNESS_BITS) | |
| 425 | (fullness & FULLNESS_MASK); |
| 426 | page->mapping = (struct address_space *)m; |
| 427 | } |
| 428 | |
Nitin Cupta | c3e3e88a | 2013-12-11 11:04:37 +0900 | [diff] [blame] | 429 | /* |
| 430 | * zsmalloc divides the pool into various size classes where each |
| 431 | * class maintains a list of zspages where each zspage is divided |
| 432 | * into equal sized chunks. Each allocation falls into one of these |
| 433 | * classes depending on its size. This function returns index of the |
| 434 | * size class which has chunk size big enough to hold the give size. |
| 435 | */ |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 436 | static int get_size_class_index(int size) |
| 437 | { |
| 438 | int idx = 0; |
| 439 | |
| 440 | if (likely(size > ZS_MIN_ALLOC_SIZE)) |
| 441 | idx = DIV_ROUND_UP(size - ZS_MIN_ALLOC_SIZE, |
| 442 | ZS_SIZE_CLASS_DELTA); |
| 443 | |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 444 | return min(zs_size_classes - 1, idx); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 445 | } |
| 446 | |
Minchan Kim | 248ca1b | 2015-04-15 16:15:42 -0700 | [diff] [blame] | 447 | #ifdef CONFIG_ZSMALLOC_STAT |
| 448 | |
| 449 | static inline void zs_stat_inc(struct size_class *class, |
| 450 | enum zs_stat_type type, unsigned long cnt) |
| 451 | { |
| 452 | class->stats.objs[type] += cnt; |
| 453 | } |
| 454 | |
| 455 | static inline void zs_stat_dec(struct size_class *class, |
| 456 | enum zs_stat_type type, unsigned long cnt) |
| 457 | { |
| 458 | class->stats.objs[type] -= cnt; |
| 459 | } |
| 460 | |
| 461 | static inline unsigned long zs_stat_get(struct size_class *class, |
| 462 | enum zs_stat_type type) |
| 463 | { |
| 464 | return class->stats.objs[type]; |
| 465 | } |
| 466 | |
| 467 | static int __init zs_stat_init(void) |
| 468 | { |
| 469 | if (!debugfs_initialized()) |
| 470 | return -ENODEV; |
| 471 | |
| 472 | zs_stat_root = debugfs_create_dir("zsmalloc", NULL); |
| 473 | if (!zs_stat_root) |
| 474 | return -ENOMEM; |
| 475 | |
| 476 | return 0; |
| 477 | } |
| 478 | |
| 479 | static void __exit zs_stat_exit(void) |
| 480 | { |
| 481 | debugfs_remove_recursive(zs_stat_root); |
| 482 | } |
| 483 | |
| 484 | static int zs_stats_size_show(struct seq_file *s, void *v) |
| 485 | { |
| 486 | int i; |
| 487 | struct zs_pool *pool = s->private; |
| 488 | struct size_class *class; |
| 489 | int objs_per_zspage; |
| 490 | unsigned long class_almost_full, class_almost_empty; |
| 491 | unsigned long obj_allocated, obj_used, pages_used; |
| 492 | unsigned long total_class_almost_full = 0, total_class_almost_empty = 0; |
| 493 | unsigned long total_objs = 0, total_used_objs = 0, total_pages = 0; |
| 494 | |
| 495 | seq_printf(s, " %5s %5s %11s %12s %13s %10s %10s %16s\n", |
| 496 | "class", "size", "almost_full", "almost_empty", |
| 497 | "obj_allocated", "obj_used", "pages_used", |
| 498 | "pages_per_zspage"); |
| 499 | |
| 500 | for (i = 0; i < zs_size_classes; i++) { |
| 501 | class = pool->size_class[i]; |
| 502 | |
| 503 | if (class->index != i) |
| 504 | continue; |
| 505 | |
| 506 | spin_lock(&class->lock); |
| 507 | class_almost_full = zs_stat_get(class, CLASS_ALMOST_FULL); |
| 508 | class_almost_empty = zs_stat_get(class, CLASS_ALMOST_EMPTY); |
| 509 | obj_allocated = zs_stat_get(class, OBJ_ALLOCATED); |
| 510 | obj_used = zs_stat_get(class, OBJ_USED); |
| 511 | spin_unlock(&class->lock); |
| 512 | |
| 513 | objs_per_zspage = get_maxobj_per_zspage(class->size, |
| 514 | class->pages_per_zspage); |
| 515 | pages_used = obj_allocated / objs_per_zspage * |
| 516 | class->pages_per_zspage; |
| 517 | |
| 518 | seq_printf(s, " %5u %5u %11lu %12lu %13lu %10lu %10lu %16d\n", |
| 519 | i, class->size, class_almost_full, class_almost_empty, |
| 520 | obj_allocated, obj_used, pages_used, |
| 521 | class->pages_per_zspage); |
| 522 | |
| 523 | total_class_almost_full += class_almost_full; |
| 524 | total_class_almost_empty += class_almost_empty; |
| 525 | total_objs += obj_allocated; |
| 526 | total_used_objs += obj_used; |
| 527 | total_pages += pages_used; |
| 528 | } |
| 529 | |
| 530 | seq_puts(s, "\n"); |
| 531 | seq_printf(s, " %5s %5s %11lu %12lu %13lu %10lu %10lu\n", |
| 532 | "Total", "", total_class_almost_full, |
| 533 | total_class_almost_empty, total_objs, |
| 534 | total_used_objs, total_pages); |
| 535 | |
| 536 | return 0; |
| 537 | } |
| 538 | |
| 539 | static int zs_stats_size_open(struct inode *inode, struct file *file) |
| 540 | { |
| 541 | return single_open(file, zs_stats_size_show, inode->i_private); |
| 542 | } |
| 543 | |
| 544 | static const struct file_operations zs_stat_size_ops = { |
| 545 | .open = zs_stats_size_open, |
| 546 | .read = seq_read, |
| 547 | .llseek = seq_lseek, |
| 548 | .release = single_release, |
| 549 | }; |
| 550 | |
| 551 | static int zs_pool_stat_create(char *name, struct zs_pool *pool) |
| 552 | { |
| 553 | struct dentry *entry; |
| 554 | |
| 555 | if (!zs_stat_root) |
| 556 | return -ENODEV; |
| 557 | |
| 558 | entry = debugfs_create_dir(name, zs_stat_root); |
| 559 | if (!entry) { |
| 560 | pr_warn("debugfs dir <%s> creation failed\n", name); |
| 561 | return -ENOMEM; |
| 562 | } |
| 563 | pool->stat_dentry = entry; |
| 564 | |
| 565 | entry = debugfs_create_file("classes", S_IFREG | S_IRUGO, |
| 566 | pool->stat_dentry, pool, &zs_stat_size_ops); |
| 567 | if (!entry) { |
| 568 | pr_warn("%s: debugfs file entry <%s> creation failed\n", |
| 569 | name, "classes"); |
| 570 | return -ENOMEM; |
| 571 | } |
| 572 | |
| 573 | return 0; |
| 574 | } |
| 575 | |
| 576 | static void zs_pool_stat_destroy(struct zs_pool *pool) |
| 577 | { |
| 578 | debugfs_remove_recursive(pool->stat_dentry); |
| 579 | } |
| 580 | |
| 581 | #else /* CONFIG_ZSMALLOC_STAT */ |
| 582 | |
| 583 | static inline void zs_stat_inc(struct size_class *class, |
| 584 | enum zs_stat_type type, unsigned long cnt) |
| 585 | { |
| 586 | } |
| 587 | |
| 588 | static inline void zs_stat_dec(struct size_class *class, |
| 589 | enum zs_stat_type type, unsigned long cnt) |
| 590 | { |
| 591 | } |
| 592 | |
| 593 | static inline unsigned long zs_stat_get(struct size_class *class, |
| 594 | enum zs_stat_type type) |
| 595 | { |
| 596 | return 0; |
| 597 | } |
| 598 | |
| 599 | static int __init zs_stat_init(void) |
| 600 | { |
| 601 | return 0; |
| 602 | } |
| 603 | |
| 604 | static void __exit zs_stat_exit(void) |
| 605 | { |
| 606 | } |
| 607 | |
| 608 | static inline int zs_pool_stat_create(char *name, struct zs_pool *pool) |
| 609 | { |
| 610 | return 0; |
| 611 | } |
| 612 | |
| 613 | static inline void zs_pool_stat_destroy(struct zs_pool *pool) |
| 614 | { |
| 615 | } |
| 616 | |
| 617 | #endif |
| 618 | |
| 619 | |
Nitin Cupta | c3e3e88a | 2013-12-11 11:04:37 +0900 | [diff] [blame] | 620 | /* |
| 621 | * For each size class, zspages are divided into different groups |
| 622 | * depending on how "full" they are. This was done so that we could |
| 623 | * easily find empty or nearly empty zspages when we try to shrink |
| 624 | * the pool (not yet implemented). This function returns fullness |
| 625 | * status of the given page. |
| 626 | */ |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 627 | static enum fullness_group get_fullness_group(struct page *page) |
| 628 | { |
| 629 | int inuse, max_objects; |
| 630 | enum fullness_group fg; |
| 631 | BUG_ON(!is_first_page(page)); |
| 632 | |
| 633 | inuse = page->inuse; |
| 634 | max_objects = page->objects; |
| 635 | |
| 636 | if (inuse == 0) |
| 637 | fg = ZS_EMPTY; |
| 638 | else if (inuse == max_objects) |
| 639 | fg = ZS_FULL; |
Minchan Kim | d3d07c9 | 2015-04-15 16:15:33 -0700 | [diff] [blame] | 640 | else if (inuse <= 3 * max_objects / fullness_threshold_frac) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 641 | fg = ZS_ALMOST_EMPTY; |
| 642 | else |
| 643 | fg = ZS_ALMOST_FULL; |
| 644 | |
| 645 | return fg; |
| 646 | } |
| 647 | |
Nitin Cupta | c3e3e88a | 2013-12-11 11:04:37 +0900 | [diff] [blame] | 648 | /* |
| 649 | * Each size class maintains various freelists and zspages are assigned |
| 650 | * to one of these freelists based on the number of live objects they |
| 651 | * have. This functions inserts the given zspage into the freelist |
| 652 | * identified by <class, fullness_group>. |
| 653 | */ |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 654 | static void insert_zspage(struct page *page, struct size_class *class, |
| 655 | enum fullness_group fullness) |
| 656 | { |
| 657 | struct page **head; |
| 658 | |
| 659 | BUG_ON(!is_first_page(page)); |
| 660 | |
| 661 | if (fullness >= _ZS_NR_FULLNESS_GROUPS) |
| 662 | return; |
| 663 | |
| 664 | head = &class->fullness_list[fullness]; |
| 665 | if (*head) |
| 666 | list_add_tail(&page->lru, &(*head)->lru); |
| 667 | |
| 668 | *head = page; |
Minchan Kim | 248ca1b | 2015-04-15 16:15:42 -0700 | [diff] [blame] | 669 | zs_stat_inc(class, fullness == ZS_ALMOST_EMPTY ? |
| 670 | CLASS_ALMOST_EMPTY : CLASS_ALMOST_FULL, 1); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 671 | } |
| 672 | |
Nitin Cupta | c3e3e88a | 2013-12-11 11:04:37 +0900 | [diff] [blame] | 673 | /* |
| 674 | * This function removes the given zspage from the freelist identified |
| 675 | * by <class, fullness_group>. |
| 676 | */ |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 677 | static void remove_zspage(struct page *page, struct size_class *class, |
| 678 | enum fullness_group fullness) |
| 679 | { |
| 680 | struct page **head; |
| 681 | |
| 682 | BUG_ON(!is_first_page(page)); |
| 683 | |
| 684 | if (fullness >= _ZS_NR_FULLNESS_GROUPS) |
| 685 | return; |
| 686 | |
| 687 | head = &class->fullness_list[fullness]; |
| 688 | BUG_ON(!*head); |
| 689 | if (list_empty(&(*head)->lru)) |
| 690 | *head = NULL; |
| 691 | else if (*head == page) |
| 692 | *head = (struct page *)list_entry((*head)->lru.next, |
| 693 | struct page, lru); |
| 694 | |
| 695 | list_del_init(&page->lru); |
Minchan Kim | 248ca1b | 2015-04-15 16:15:42 -0700 | [diff] [blame] | 696 | zs_stat_dec(class, fullness == ZS_ALMOST_EMPTY ? |
| 697 | CLASS_ALMOST_EMPTY : CLASS_ALMOST_FULL, 1); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 698 | } |
| 699 | |
Nitin Cupta | c3e3e88a | 2013-12-11 11:04:37 +0900 | [diff] [blame] | 700 | /* |
| 701 | * Each size class maintains zspages in different fullness groups depending |
| 702 | * on the number of live objects they contain. When allocating or freeing |
| 703 | * objects, the fullness status of the page can change, say, from ALMOST_FULL |
| 704 | * to ALMOST_EMPTY when freeing an object. This function checks if such |
| 705 | * a status change has occurred for the given page and accordingly moves the |
| 706 | * page from the freelist of the old fullness group to that of the new |
| 707 | * fullness group. |
| 708 | */ |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 709 | static enum fullness_group fix_fullness_group(struct size_class *class, |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 710 | struct page *page) |
| 711 | { |
| 712 | int class_idx; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 713 | enum fullness_group currfg, newfg; |
| 714 | |
| 715 | BUG_ON(!is_first_page(page)); |
| 716 | |
| 717 | get_zspage_mapping(page, &class_idx, &currfg); |
| 718 | newfg = get_fullness_group(page); |
| 719 | if (newfg == currfg) |
| 720 | goto out; |
| 721 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 722 | remove_zspage(page, class, currfg); |
| 723 | insert_zspage(page, class, newfg); |
| 724 | set_zspage_mapping(page, class_idx, newfg); |
| 725 | |
| 726 | out: |
| 727 | return newfg; |
| 728 | } |
| 729 | |
| 730 | /* |
| 731 | * We have to decide on how many pages to link together |
| 732 | * to form a zspage for each size class. This is important |
| 733 | * to reduce wastage due to unusable space left at end of |
| 734 | * each zspage which is given as: |
Yinghao Xie | 888fa374 | 2015-04-15 16:15:49 -0700 | [diff] [blame] | 735 | * wastage = Zp % class_size |
| 736 | * usage = Zp - wastage |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 737 | * where Zp = zspage size = k * PAGE_SIZE where k = 1, 2, ... |
| 738 | * |
| 739 | * For example, for size class of 3/8 * PAGE_SIZE, we should |
| 740 | * link together 3 PAGE_SIZE sized pages to form a zspage |
| 741 | * since then we can perfectly fit in 8 such objects. |
| 742 | */ |
Minchan Kim | 2e3b6154 | 2012-05-03 15:40:39 +0900 | [diff] [blame] | 743 | static int get_pages_per_zspage(int class_size) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 744 | { |
| 745 | int i, max_usedpc = 0; |
| 746 | /* zspage order which gives maximum used size per KB */ |
| 747 | int max_usedpc_order = 1; |
| 748 | |
Seth Jennings | 84d4faa | 2012-03-05 11:33:21 -0600 | [diff] [blame] | 749 | for (i = 1; i <= ZS_MAX_PAGES_PER_ZSPAGE; i++) { |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 750 | int zspage_size; |
| 751 | int waste, usedpc; |
| 752 | |
| 753 | zspage_size = i * PAGE_SIZE; |
| 754 | waste = zspage_size % class_size; |
| 755 | usedpc = (zspage_size - waste) * 100 / zspage_size; |
| 756 | |
| 757 | if (usedpc > max_usedpc) { |
| 758 | max_usedpc = usedpc; |
| 759 | max_usedpc_order = i; |
| 760 | } |
| 761 | } |
| 762 | |
| 763 | return max_usedpc_order; |
| 764 | } |
| 765 | |
| 766 | /* |
| 767 | * A single 'zspage' is composed of many system pages which are |
| 768 | * linked together using fields in struct page. This function finds |
| 769 | * the first/head page, given any component page of a zspage. |
| 770 | */ |
| 771 | static struct page *get_first_page(struct page *page) |
| 772 | { |
| 773 | if (is_first_page(page)) |
| 774 | return page; |
| 775 | else |
| 776 | return page->first_page; |
| 777 | } |
| 778 | |
| 779 | static struct page *get_next_page(struct page *page) |
| 780 | { |
| 781 | struct page *next; |
| 782 | |
| 783 | if (is_last_page(page)) |
| 784 | next = NULL; |
| 785 | else if (is_first_page(page)) |
Sunghan Suh | e842b97 | 2013-07-12 16:08:13 +0900 | [diff] [blame] | 786 | next = (struct page *)page_private(page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 787 | else |
| 788 | next = list_entry(page->lru.next, struct page, lru); |
| 789 | |
| 790 | return next; |
| 791 | } |
| 792 | |
Olav Haugan | 6729687 | 2013-11-22 09:30:41 -0800 | [diff] [blame] | 793 | /* |
| 794 | * Encode <page, obj_idx> as a single handle value. |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 795 | * We use the least bit of handle for tagging. |
Olav Haugan | 6729687 | 2013-11-22 09:30:41 -0800 | [diff] [blame] | 796 | */ |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 797 | static void *location_to_obj(struct page *page, unsigned long obj_idx) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 798 | { |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 799 | unsigned long obj; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 800 | |
| 801 | if (!page) { |
| 802 | BUG_ON(obj_idx); |
| 803 | return NULL; |
| 804 | } |
| 805 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 806 | obj = page_to_pfn(page) << OBJ_INDEX_BITS; |
| 807 | obj |= ((obj_idx) & OBJ_INDEX_MASK); |
| 808 | obj <<= OBJ_TAG_BITS; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 809 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 810 | return (void *)obj; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 811 | } |
| 812 | |
Olav Haugan | 6729687 | 2013-11-22 09:30:41 -0800 | [diff] [blame] | 813 | /* |
| 814 | * Decode <page, obj_idx> pair from the given object handle. We adjust the |
| 815 | * decoded obj_idx back to its original value since it was adjusted in |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 816 | * location_to_obj(). |
Olav Haugan | 6729687 | 2013-11-22 09:30:41 -0800 | [diff] [blame] | 817 | */ |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 818 | static void obj_to_location(unsigned long obj, struct page **page, |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 819 | unsigned long *obj_idx) |
| 820 | { |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 821 | obj >>= OBJ_TAG_BITS; |
| 822 | *page = pfn_to_page(obj >> OBJ_INDEX_BITS); |
| 823 | *obj_idx = (obj & OBJ_INDEX_MASK); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 824 | } |
| 825 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 826 | static unsigned long handle_to_obj(unsigned long handle) |
| 827 | { |
| 828 | return *(unsigned long *)handle; |
| 829 | } |
| 830 | |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 831 | static unsigned long obj_to_head(struct size_class *class, struct page *page, |
| 832 | void *obj) |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 833 | { |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 834 | if (class->huge) { |
| 835 | VM_BUG_ON(!is_first_page(page)); |
| 836 | return *(unsigned long *)page_private(page); |
| 837 | } else |
| 838 | return *(unsigned long *)obj; |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 839 | } |
| 840 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 841 | static unsigned long obj_idx_to_offset(struct page *page, |
| 842 | unsigned long obj_idx, int class_size) |
| 843 | { |
| 844 | unsigned long off = 0; |
| 845 | |
| 846 | if (!is_first_page(page)) |
| 847 | off = page->index; |
| 848 | |
| 849 | return off + obj_idx * class_size; |
| 850 | } |
| 851 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 852 | static inline int trypin_tag(unsigned long handle) |
| 853 | { |
| 854 | unsigned long *ptr = (unsigned long *)handle; |
| 855 | |
| 856 | return !test_and_set_bit_lock(HANDLE_PIN_BIT, ptr); |
| 857 | } |
| 858 | |
| 859 | static void pin_tag(unsigned long handle) |
| 860 | { |
| 861 | while (!trypin_tag(handle)); |
| 862 | } |
| 863 | |
| 864 | static void unpin_tag(unsigned long handle) |
| 865 | { |
| 866 | unsigned long *ptr = (unsigned long *)handle; |
| 867 | |
| 868 | clear_bit_unlock(HANDLE_PIN_BIT, ptr); |
| 869 | } |
| 870 | |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 871 | static void reset_page(struct page *page) |
| 872 | { |
| 873 | clear_bit(PG_private, &page->flags); |
| 874 | clear_bit(PG_private_2, &page->flags); |
| 875 | set_page_private(page, 0); |
| 876 | page->mapping = NULL; |
| 877 | page->freelist = NULL; |
Mel Gorman | 22b751c | 2013-02-22 16:34:59 -0800 | [diff] [blame] | 878 | page_mapcount_reset(page); |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 879 | } |
| 880 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 881 | static void free_zspage(struct page *first_page) |
| 882 | { |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 883 | struct page *nextp, *tmp, *head_extra; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 884 | |
| 885 | BUG_ON(!is_first_page(first_page)); |
| 886 | BUG_ON(first_page->inuse); |
| 887 | |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 888 | head_extra = (struct page *)page_private(first_page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 889 | |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 890 | reset_page(first_page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 891 | __free_page(first_page); |
| 892 | |
| 893 | /* zspage with only 1 system page */ |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 894 | if (!head_extra) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 895 | return; |
| 896 | |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 897 | list_for_each_entry_safe(nextp, tmp, &head_extra->lru, lru) { |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 898 | list_del(&nextp->lru); |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 899 | reset_page(nextp); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 900 | __free_page(nextp); |
| 901 | } |
Nitin Gupta | f4477e9 | 2012-04-02 09:13:56 -0500 | [diff] [blame] | 902 | reset_page(head_extra); |
| 903 | __free_page(head_extra); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 904 | } |
| 905 | |
| 906 | /* Initialize a newly allocated zspage */ |
| 907 | static void init_zspage(struct page *first_page, struct size_class *class) |
| 908 | { |
| 909 | unsigned long off = 0; |
| 910 | struct page *page = first_page; |
| 911 | |
| 912 | BUG_ON(!is_first_page(first_page)); |
| 913 | while (page) { |
| 914 | struct page *next_page; |
| 915 | struct link_free *link; |
Dan Streetman | 5538c56 | 2014-10-09 15:30:01 -0700 | [diff] [blame] | 916 | unsigned int i = 1; |
Minchan Kim | af4ee5e | 2014-12-12 16:56:58 -0800 | [diff] [blame] | 917 | void *vaddr; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 918 | |
| 919 | /* |
| 920 | * page->index stores offset of first object starting |
| 921 | * in the page. For the first page, this is always 0, |
| 922 | * so we use first_page->index (aka ->freelist) to store |
| 923 | * head of corresponding zspage's freelist. |
| 924 | */ |
| 925 | if (page != first_page) |
| 926 | page->index = off; |
| 927 | |
Minchan Kim | af4ee5e | 2014-12-12 16:56:58 -0800 | [diff] [blame] | 928 | vaddr = kmap_atomic(page); |
| 929 | link = (struct link_free *)vaddr + off / sizeof(*link); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 930 | |
Dan Streetman | 5538c56 | 2014-10-09 15:30:01 -0700 | [diff] [blame] | 931 | while ((off += class->size) < PAGE_SIZE) { |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 932 | link->next = location_to_obj(page, i++); |
Dan Streetman | 5538c56 | 2014-10-09 15:30:01 -0700 | [diff] [blame] | 933 | link += class->size / sizeof(*link); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 934 | } |
| 935 | |
| 936 | /* |
| 937 | * We now come to the last (full or partial) object on this |
| 938 | * page, which must point to the first object on the next |
| 939 | * page (if present) |
| 940 | */ |
| 941 | next_page = get_next_page(page); |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 942 | link->next = location_to_obj(next_page, 0); |
Minchan Kim | af4ee5e | 2014-12-12 16:56:58 -0800 | [diff] [blame] | 943 | kunmap_atomic(vaddr); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 944 | page = next_page; |
Dan Streetman | 5538c56 | 2014-10-09 15:30:01 -0700 | [diff] [blame] | 945 | off %= PAGE_SIZE; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 946 | } |
| 947 | } |
| 948 | |
| 949 | /* |
| 950 | * Allocate a zspage for the given size class |
| 951 | */ |
| 952 | static struct page *alloc_zspage(struct size_class *class, gfp_t flags) |
| 953 | { |
| 954 | int i, error; |
Seth Jennings | b4b700c | 2012-06-13 16:03:42 -0500 | [diff] [blame] | 955 | struct page *first_page = NULL, *uninitialized_var(prev_page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 956 | |
| 957 | /* |
| 958 | * Allocate individual pages and link them together as: |
| 959 | * 1. first page->private = first sub-page |
| 960 | * 2. all sub-pages are linked together using page->lru |
| 961 | * 3. each sub-page is linked to the first page using page->first_page |
| 962 | * |
| 963 | * For each size class, First/Head pages are linked together using |
| 964 | * page->lru. Also, we set PG_private to identify the first page |
| 965 | * (i.e. no other sub-page has this flag set) and PG_private_2 to |
| 966 | * identify the last page. |
| 967 | */ |
| 968 | error = -ENOMEM; |
Minchan Kim | 2e3b6154 | 2012-05-03 15:40:39 +0900 | [diff] [blame] | 969 | for (i = 0; i < class->pages_per_zspage; i++) { |
Seth Jennings | b4b700c | 2012-06-13 16:03:42 -0500 | [diff] [blame] | 970 | struct page *page; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 971 | |
| 972 | page = alloc_page(flags); |
| 973 | if (!page) |
| 974 | goto cleanup; |
| 975 | |
| 976 | INIT_LIST_HEAD(&page->lru); |
| 977 | if (i == 0) { /* first page */ |
Minchan Kim | a27545bf | 2012-04-25 15:23:09 +0900 | [diff] [blame] | 978 | SetPagePrivate(page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 979 | set_page_private(page, 0); |
| 980 | first_page = page; |
| 981 | first_page->inuse = 0; |
| 982 | } |
| 983 | if (i == 1) |
Sunghan Suh | e842b97 | 2013-07-12 16:08:13 +0900 | [diff] [blame] | 984 | set_page_private(first_page, (unsigned long)page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 985 | if (i >= 1) |
| 986 | page->first_page = first_page; |
| 987 | if (i >= 2) |
| 988 | list_add(&page->lru, &prev_page->lru); |
Minchan Kim | 2e3b6154 | 2012-05-03 15:40:39 +0900 | [diff] [blame] | 989 | if (i == class->pages_per_zspage - 1) /* last page */ |
Minchan Kim | a27545bf | 2012-04-25 15:23:09 +0900 | [diff] [blame] | 990 | SetPagePrivate2(page); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 991 | prev_page = page; |
| 992 | } |
| 993 | |
| 994 | init_zspage(first_page, class); |
| 995 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 996 | first_page->freelist = location_to_obj(first_page, 0); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 997 | /* Maximum number of objects we can store in this zspage */ |
Minchan Kim | 2e3b6154 | 2012-05-03 15:40:39 +0900 | [diff] [blame] | 998 | first_page->objects = class->pages_per_zspage * PAGE_SIZE / class->size; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 999 | |
| 1000 | error = 0; /* Success */ |
| 1001 | |
| 1002 | cleanup: |
| 1003 | if (unlikely(error) && first_page) { |
| 1004 | free_zspage(first_page); |
| 1005 | first_page = NULL; |
| 1006 | } |
| 1007 | |
| 1008 | return first_page; |
| 1009 | } |
| 1010 | |
| 1011 | static struct page *find_get_zspage(struct size_class *class) |
| 1012 | { |
| 1013 | int i; |
| 1014 | struct page *page; |
| 1015 | |
| 1016 | for (i = 0; i < _ZS_NR_FULLNESS_GROUPS; i++) { |
| 1017 | page = class->fullness_list[i]; |
| 1018 | if (page) |
| 1019 | break; |
| 1020 | } |
| 1021 | |
| 1022 | return page; |
| 1023 | } |
| 1024 | |
Minchan Kim | 1b945ae | 2013-12-11 11:04:36 +0900 | [diff] [blame] | 1025 | #ifdef CONFIG_PGTABLE_MAPPING |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1026 | static inline int __zs_cpu_up(struct mapping_area *area) |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1027 | { |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1028 | /* |
| 1029 | * Make sure we don't leak memory if a cpu UP notification |
| 1030 | * and zs_init() race and both call zs_cpu_up() on the same cpu |
| 1031 | */ |
| 1032 | if (area->vm) |
| 1033 | return 0; |
| 1034 | area->vm = alloc_vm_area(PAGE_SIZE * 2, NULL); |
| 1035 | if (!area->vm) |
| 1036 | return -ENOMEM; |
| 1037 | return 0; |
| 1038 | } |
| 1039 | |
| 1040 | static inline void __zs_cpu_down(struct mapping_area *area) |
| 1041 | { |
| 1042 | if (area->vm) |
| 1043 | free_vm_area(area->vm); |
| 1044 | area->vm = NULL; |
| 1045 | } |
| 1046 | |
| 1047 | static inline void *__zs_map_object(struct mapping_area *area, |
| 1048 | struct page *pages[2], int off, int size) |
| 1049 | { |
WANG Chao | f6f8ed4 | 2014-08-06 16:06:58 -0700 | [diff] [blame] | 1050 | BUG_ON(map_vm_area(area->vm, PAGE_KERNEL, pages)); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1051 | area->vm_addr = area->vm->addr; |
| 1052 | return area->vm_addr + off; |
| 1053 | } |
| 1054 | |
| 1055 | static inline void __zs_unmap_object(struct mapping_area *area, |
| 1056 | struct page *pages[2], int off, int size) |
| 1057 | { |
| 1058 | unsigned long addr = (unsigned long)area->vm_addr; |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1059 | |
Joerg Roedel | d95abbb | 2013-03-27 01:43:14 +0100 | [diff] [blame] | 1060 | unmap_kernel_range(addr, PAGE_SIZE * 2); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1061 | } |
| 1062 | |
Minchan Kim | 1b945ae | 2013-12-11 11:04:36 +0900 | [diff] [blame] | 1063 | #else /* CONFIG_PGTABLE_MAPPING */ |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1064 | |
| 1065 | static inline int __zs_cpu_up(struct mapping_area *area) |
| 1066 | { |
| 1067 | /* |
| 1068 | * Make sure we don't leak memory if a cpu UP notification |
| 1069 | * and zs_init() race and both call zs_cpu_up() on the same cpu |
| 1070 | */ |
| 1071 | if (area->vm_buf) |
| 1072 | return 0; |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1073 | area->vm_buf = kmalloc(ZS_MAX_ALLOC_SIZE, GFP_KERNEL); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1074 | if (!area->vm_buf) |
| 1075 | return -ENOMEM; |
| 1076 | return 0; |
| 1077 | } |
| 1078 | |
| 1079 | static inline void __zs_cpu_down(struct mapping_area *area) |
| 1080 | { |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1081 | kfree(area->vm_buf); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1082 | area->vm_buf = NULL; |
| 1083 | } |
| 1084 | |
| 1085 | static void *__zs_map_object(struct mapping_area *area, |
| 1086 | struct page *pages[2], int off, int size) |
| 1087 | { |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1088 | int sizes[2]; |
| 1089 | void *addr; |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1090 | char *buf = area->vm_buf; |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1091 | |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1092 | /* disable page faults to match kmap_atomic() return conditions */ |
| 1093 | pagefault_disable(); |
| 1094 | |
| 1095 | /* no read fastpath */ |
| 1096 | if (area->vm_mm == ZS_MM_WO) |
| 1097 | goto out; |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1098 | |
| 1099 | sizes[0] = PAGE_SIZE - off; |
| 1100 | sizes[1] = size - sizes[0]; |
| 1101 | |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1102 | /* copy object to per-cpu buffer */ |
| 1103 | addr = kmap_atomic(pages[0]); |
| 1104 | memcpy(buf, addr + off, sizes[0]); |
| 1105 | kunmap_atomic(addr); |
| 1106 | addr = kmap_atomic(pages[1]); |
| 1107 | memcpy(buf + sizes[0], addr, sizes[1]); |
| 1108 | kunmap_atomic(addr); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1109 | out: |
| 1110 | return area->vm_buf; |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1111 | } |
| 1112 | |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1113 | static void __zs_unmap_object(struct mapping_area *area, |
| 1114 | struct page *pages[2], int off, int size) |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1115 | { |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1116 | int sizes[2]; |
| 1117 | void *addr; |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1118 | char *buf; |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1119 | |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1120 | /* no write fastpath */ |
| 1121 | if (area->vm_mm == ZS_MM_RO) |
| 1122 | goto out; |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1123 | |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1124 | buf = area->vm_buf; |
| 1125 | if (!area->huge) { |
| 1126 | buf = buf + ZS_HANDLE_SIZE; |
| 1127 | size -= ZS_HANDLE_SIZE; |
| 1128 | off += ZS_HANDLE_SIZE; |
| 1129 | } |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1130 | |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1131 | sizes[0] = PAGE_SIZE - off; |
| 1132 | sizes[1] = size - sizes[0]; |
| 1133 | |
| 1134 | /* copy per-cpu buffer to object */ |
| 1135 | addr = kmap_atomic(pages[0]); |
| 1136 | memcpy(addr + off, buf, sizes[0]); |
| 1137 | kunmap_atomic(addr); |
| 1138 | addr = kmap_atomic(pages[1]); |
| 1139 | memcpy(addr, buf + sizes[0], sizes[1]); |
| 1140 | kunmap_atomic(addr); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1141 | |
| 1142 | out: |
| 1143 | /* enable page faults to match kunmap_atomic() return conditions */ |
| 1144 | pagefault_enable(); |
Seth Jennings | 5f601902 | 2012-07-02 16:15:49 -0500 | [diff] [blame] | 1145 | } |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1146 | |
Minchan Kim | 1b945ae | 2013-12-11 11:04:36 +0900 | [diff] [blame] | 1147 | #endif /* CONFIG_PGTABLE_MAPPING */ |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1148 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1149 | static int zs_cpu_notifier(struct notifier_block *nb, unsigned long action, |
| 1150 | void *pcpu) |
| 1151 | { |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1152 | int ret, cpu = (long)pcpu; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1153 | struct mapping_area *area; |
| 1154 | |
| 1155 | switch (action) { |
| 1156 | case CPU_UP_PREPARE: |
| 1157 | area = &per_cpu(zs_map_area, cpu); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1158 | ret = __zs_cpu_up(area); |
| 1159 | if (ret) |
| 1160 | return notifier_from_errno(ret); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1161 | break; |
| 1162 | case CPU_DEAD: |
| 1163 | case CPU_UP_CANCELED: |
| 1164 | area = &per_cpu(zs_map_area, cpu); |
Seth Jennings | f553646 | 2012-07-18 11:55:56 -0500 | [diff] [blame] | 1165 | __zs_cpu_down(area); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1166 | break; |
| 1167 | } |
| 1168 | |
| 1169 | return NOTIFY_OK; |
| 1170 | } |
| 1171 | |
| 1172 | static struct notifier_block zs_cpu_nb = { |
| 1173 | .notifier_call = zs_cpu_notifier |
| 1174 | }; |
| 1175 | |
Sergey Senozhatsky | b1b00a5 | 2014-12-12 16:56:56 -0800 | [diff] [blame] | 1176 | static int zs_register_cpu_notifier(void) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1177 | { |
Sergey Senozhatsky | b1b00a5 | 2014-12-12 16:56:56 -0800 | [diff] [blame] | 1178 | int cpu, uninitialized_var(ret); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1179 | |
Srivatsa S. Bhat | f0e71fc | 2014-03-11 02:09:59 +0530 | [diff] [blame] | 1180 | cpu_notifier_register_begin(); |
| 1181 | |
| 1182 | __register_cpu_notifier(&zs_cpu_nb); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1183 | for_each_online_cpu(cpu) { |
| 1184 | ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu); |
Sergey Senozhatsky | b1b00a5 | 2014-12-12 16:56:56 -0800 | [diff] [blame] | 1185 | if (notifier_to_errno(ret)) |
| 1186 | break; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1187 | } |
Srivatsa S. Bhat | f0e71fc | 2014-03-11 02:09:59 +0530 | [diff] [blame] | 1188 | |
| 1189 | cpu_notifier_register_done(); |
Sergey Senozhatsky | b1b00a5 | 2014-12-12 16:56:56 -0800 | [diff] [blame] | 1190 | return notifier_to_errno(ret); |
| 1191 | } |
| 1192 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1193 | static void zs_unregister_cpu_notifier(void) |
| 1194 | { |
| 1195 | int cpu; |
| 1196 | |
| 1197 | cpu_notifier_register_begin(); |
| 1198 | |
| 1199 | for_each_online_cpu(cpu) |
| 1200 | zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu); |
| 1201 | __unregister_cpu_notifier(&zs_cpu_nb); |
| 1202 | |
| 1203 | cpu_notifier_register_done(); |
| 1204 | } |
| 1205 | |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1206 | static void init_zs_size_classes(void) |
| 1207 | { |
| 1208 | int nr; |
| 1209 | |
| 1210 | nr = (ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) / ZS_SIZE_CLASS_DELTA + 1; |
| 1211 | if ((ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) % ZS_SIZE_CLASS_DELTA) |
| 1212 | nr += 1; |
| 1213 | |
| 1214 | zs_size_classes = nr; |
| 1215 | } |
| 1216 | |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1217 | static bool can_merge(struct size_class *prev, int size, int pages_per_zspage) |
| 1218 | { |
| 1219 | if (prev->pages_per_zspage != pages_per_zspage) |
| 1220 | return false; |
| 1221 | |
| 1222 | if (get_maxobj_per_zspage(prev->size, prev->pages_per_zspage) |
| 1223 | != get_maxobj_per_zspage(size, pages_per_zspage)) |
| 1224 | return false; |
| 1225 | |
| 1226 | return true; |
| 1227 | } |
| 1228 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1229 | static bool zspage_full(struct page *page) |
| 1230 | { |
| 1231 | BUG_ON(!is_first_page(page)); |
| 1232 | |
| 1233 | return page->inuse == page->objects; |
| 1234 | } |
| 1235 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1236 | unsigned long zs_get_total_pages(struct zs_pool *pool) |
| 1237 | { |
| 1238 | return atomic_long_read(&pool->pages_allocated); |
| 1239 | } |
| 1240 | EXPORT_SYMBOL_GPL(zs_get_total_pages); |
| 1241 | |
| 1242 | /** |
| 1243 | * zs_map_object - get address of allocated object from handle. |
| 1244 | * @pool: pool from which the object was allocated |
| 1245 | * @handle: handle returned from zs_malloc |
| 1246 | * |
| 1247 | * Before using an object allocated from zs_malloc, it must be mapped using |
| 1248 | * this function. When done with the object, it must be unmapped using |
| 1249 | * zs_unmap_object. |
| 1250 | * |
| 1251 | * Only one object can be mapped per cpu at a time. There is no protection |
| 1252 | * against nested mappings. |
| 1253 | * |
| 1254 | * This function returns with preemption and page faults disabled. |
| 1255 | */ |
| 1256 | void *zs_map_object(struct zs_pool *pool, unsigned long handle, |
| 1257 | enum zs_mapmode mm) |
| 1258 | { |
| 1259 | struct page *page; |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1260 | unsigned long obj, obj_idx, off; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1261 | |
| 1262 | unsigned int class_idx; |
| 1263 | enum fullness_group fg; |
| 1264 | struct size_class *class; |
| 1265 | struct mapping_area *area; |
| 1266 | struct page *pages[2]; |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1267 | void *ret; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1268 | |
| 1269 | BUG_ON(!handle); |
| 1270 | |
| 1271 | /* |
| 1272 | * Because we use per-cpu mapping areas shared among the |
| 1273 | * pools/users, we can't allow mapping in interrupt context |
| 1274 | * because it can corrupt another users mappings. |
| 1275 | */ |
| 1276 | BUG_ON(in_interrupt()); |
| 1277 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1278 | /* From now on, migration cannot move the object */ |
| 1279 | pin_tag(handle); |
| 1280 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1281 | obj = handle_to_obj(handle); |
| 1282 | obj_to_location(obj, &page, &obj_idx); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1283 | get_zspage_mapping(get_first_page(page), &class_idx, &fg); |
| 1284 | class = pool->size_class[class_idx]; |
| 1285 | off = obj_idx_to_offset(page, obj_idx, class->size); |
| 1286 | |
| 1287 | area = &get_cpu_var(zs_map_area); |
| 1288 | area->vm_mm = mm; |
| 1289 | if (off + class->size <= PAGE_SIZE) { |
| 1290 | /* this object is contained entirely within a page */ |
| 1291 | area->vm_addr = kmap_atomic(page); |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1292 | ret = area->vm_addr + off; |
| 1293 | goto out; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1294 | } |
| 1295 | |
| 1296 | /* this object spans two pages */ |
| 1297 | pages[0] = page; |
| 1298 | pages[1] = get_next_page(page); |
| 1299 | BUG_ON(!pages[1]); |
| 1300 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1301 | ret = __zs_map_object(area, pages, off, class->size); |
| 1302 | out: |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1303 | if (!class->huge) |
| 1304 | ret += ZS_HANDLE_SIZE; |
| 1305 | |
| 1306 | return ret; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1307 | } |
| 1308 | EXPORT_SYMBOL_GPL(zs_map_object); |
| 1309 | |
| 1310 | void zs_unmap_object(struct zs_pool *pool, unsigned long handle) |
| 1311 | { |
| 1312 | struct page *page; |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1313 | unsigned long obj, obj_idx, off; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1314 | |
| 1315 | unsigned int class_idx; |
| 1316 | enum fullness_group fg; |
| 1317 | struct size_class *class; |
| 1318 | struct mapping_area *area; |
| 1319 | |
| 1320 | BUG_ON(!handle); |
| 1321 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1322 | obj = handle_to_obj(handle); |
| 1323 | obj_to_location(obj, &page, &obj_idx); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1324 | get_zspage_mapping(get_first_page(page), &class_idx, &fg); |
| 1325 | class = pool->size_class[class_idx]; |
| 1326 | off = obj_idx_to_offset(page, obj_idx, class->size); |
| 1327 | |
| 1328 | area = this_cpu_ptr(&zs_map_area); |
| 1329 | if (off + class->size <= PAGE_SIZE) |
| 1330 | kunmap_atomic(area->vm_addr); |
| 1331 | else { |
| 1332 | struct page *pages[2]; |
| 1333 | |
| 1334 | pages[0] = page; |
| 1335 | pages[1] = get_next_page(page); |
| 1336 | BUG_ON(!pages[1]); |
| 1337 | |
| 1338 | __zs_unmap_object(area, pages, off, class->size); |
| 1339 | } |
| 1340 | put_cpu_var(zs_map_area); |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1341 | unpin_tag(handle); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1342 | } |
| 1343 | EXPORT_SYMBOL_GPL(zs_unmap_object); |
| 1344 | |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1345 | static unsigned long obj_malloc(struct page *first_page, |
| 1346 | struct size_class *class, unsigned long handle) |
| 1347 | { |
| 1348 | unsigned long obj; |
| 1349 | struct link_free *link; |
| 1350 | |
| 1351 | struct page *m_page; |
| 1352 | unsigned long m_objidx, m_offset; |
| 1353 | void *vaddr; |
| 1354 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1355 | handle |= OBJ_ALLOCATED_TAG; |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1356 | obj = (unsigned long)first_page->freelist; |
| 1357 | obj_to_location(obj, &m_page, &m_objidx); |
| 1358 | m_offset = obj_idx_to_offset(m_page, m_objidx, class->size); |
| 1359 | |
| 1360 | vaddr = kmap_atomic(m_page); |
| 1361 | link = (struct link_free *)vaddr + m_offset / sizeof(*link); |
| 1362 | first_page->freelist = link->next; |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1363 | if (!class->huge) |
| 1364 | /* record handle in the header of allocated chunk */ |
| 1365 | link->handle = handle; |
| 1366 | else |
| 1367 | /* record handle in first_page->private */ |
| 1368 | set_page_private(first_page, handle); |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1369 | kunmap_atomic(vaddr); |
| 1370 | first_page->inuse++; |
| 1371 | zs_stat_inc(class, OBJ_USED, 1); |
| 1372 | |
| 1373 | return obj; |
| 1374 | } |
| 1375 | |
| 1376 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1377 | /** |
| 1378 | * zs_malloc - Allocate block of given size from pool. |
| 1379 | * @pool: pool to allocate from |
| 1380 | * @size: size of block to allocate |
| 1381 | * |
| 1382 | * On success, handle to the allocated object is returned, |
| 1383 | * otherwise 0. |
| 1384 | * Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail. |
| 1385 | */ |
| 1386 | unsigned long zs_malloc(struct zs_pool *pool, size_t size) |
| 1387 | { |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1388 | unsigned long handle, obj; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1389 | struct size_class *class; |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1390 | struct page *first_page; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1391 | |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1392 | if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE)) |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1393 | return 0; |
| 1394 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1395 | handle = alloc_handle(pool); |
| 1396 | if (!handle) |
| 1397 | return 0; |
| 1398 | |
| 1399 | /* extra space in chunk to keep the handle */ |
| 1400 | size += ZS_HANDLE_SIZE; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1401 | class = pool->size_class[get_size_class_index(size)]; |
| 1402 | |
| 1403 | spin_lock(&class->lock); |
| 1404 | first_page = find_get_zspage(class); |
| 1405 | |
| 1406 | if (!first_page) { |
| 1407 | spin_unlock(&class->lock); |
| 1408 | first_page = alloc_zspage(class, pool->flags); |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1409 | if (unlikely(!first_page)) { |
| 1410 | free_handle(pool, handle); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1411 | return 0; |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1412 | } |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1413 | |
| 1414 | set_zspage_mapping(first_page, class->index, ZS_EMPTY); |
| 1415 | atomic_long_add(class->pages_per_zspage, |
| 1416 | &pool->pages_allocated); |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1417 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1418 | spin_lock(&class->lock); |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1419 | zs_stat_inc(class, OBJ_ALLOCATED, get_maxobj_per_zspage( |
| 1420 | class->size, class->pages_per_zspage)); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1421 | } |
| 1422 | |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1423 | obj = obj_malloc(first_page, class, handle); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1424 | /* Now move the zspage to another fullness group, if required */ |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1425 | fix_fullness_group(class, first_page); |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1426 | record_obj(handle, obj); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1427 | spin_unlock(&class->lock); |
| 1428 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1429 | return handle; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1430 | } |
| 1431 | EXPORT_SYMBOL_GPL(zs_malloc); |
| 1432 | |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1433 | static void obj_free(struct zs_pool *pool, struct size_class *class, |
| 1434 | unsigned long obj) |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1435 | { |
| 1436 | struct link_free *link; |
| 1437 | struct page *first_page, *f_page; |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1438 | unsigned long f_objidx, f_offset; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1439 | void *vaddr; |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1440 | int class_idx; |
| 1441 | enum fullness_group fullness; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1442 | |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1443 | BUG_ON(!obj); |
| 1444 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1445 | obj &= ~OBJ_ALLOCATED_TAG; |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1446 | obj_to_location(obj, &f_page, &f_objidx); |
| 1447 | first_page = get_first_page(f_page); |
| 1448 | |
| 1449 | get_zspage_mapping(first_page, &class_idx, &fullness); |
| 1450 | f_offset = obj_idx_to_offset(f_page, f_objidx, class->size); |
| 1451 | |
| 1452 | vaddr = kmap_atomic(f_page); |
| 1453 | |
| 1454 | /* Insert this object in containing zspage's freelist */ |
| 1455 | link = (struct link_free *)(vaddr + f_offset); |
| 1456 | link->next = first_page->freelist; |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1457 | if (class->huge) |
| 1458 | set_page_private(first_page, 0); |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1459 | kunmap_atomic(vaddr); |
| 1460 | first_page->freelist = (void *)obj; |
| 1461 | first_page->inuse--; |
| 1462 | zs_stat_dec(class, OBJ_USED, 1); |
| 1463 | } |
| 1464 | |
| 1465 | void zs_free(struct zs_pool *pool, unsigned long handle) |
| 1466 | { |
| 1467 | struct page *first_page, *f_page; |
| 1468 | unsigned long obj, f_objidx; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1469 | int class_idx; |
| 1470 | struct size_class *class; |
| 1471 | enum fullness_group fullness; |
| 1472 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1473 | if (unlikely(!handle)) |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1474 | return; |
| 1475 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1476 | pin_tag(handle); |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1477 | obj = handle_to_obj(handle); |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1478 | obj_to_location(obj, &f_page, &f_objidx); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1479 | first_page = get_first_page(f_page); |
| 1480 | |
| 1481 | get_zspage_mapping(first_page, &class_idx, &fullness); |
| 1482 | class = pool->size_class[class_idx]; |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1483 | |
| 1484 | spin_lock(&class->lock); |
Minchan Kim | c780626 | 2015-04-15 16:15:26 -0700 | [diff] [blame] | 1485 | obj_free(pool, class, obj); |
| 1486 | fullness = fix_fullness_group(class, first_page); |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1487 | if (fullness == ZS_EMPTY) { |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1488 | zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage( |
| 1489 | class->size, class->pages_per_zspage)); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1490 | atomic_long_sub(class->pages_per_zspage, |
| 1491 | &pool->pages_allocated); |
| 1492 | free_zspage(first_page); |
| 1493 | } |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1494 | spin_unlock(&class->lock); |
| 1495 | unpin_tag(handle); |
| 1496 | |
| 1497 | free_handle(pool, handle); |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1498 | } |
| 1499 | EXPORT_SYMBOL_GPL(zs_free); |
| 1500 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1501 | static void zs_object_copy(unsigned long src, unsigned long dst, |
| 1502 | struct size_class *class) |
| 1503 | { |
| 1504 | struct page *s_page, *d_page; |
| 1505 | unsigned long s_objidx, d_objidx; |
| 1506 | unsigned long s_off, d_off; |
| 1507 | void *s_addr, *d_addr; |
| 1508 | int s_size, d_size, size; |
| 1509 | int written = 0; |
| 1510 | |
| 1511 | s_size = d_size = class->size; |
| 1512 | |
| 1513 | obj_to_location(src, &s_page, &s_objidx); |
| 1514 | obj_to_location(dst, &d_page, &d_objidx); |
| 1515 | |
| 1516 | s_off = obj_idx_to_offset(s_page, s_objidx, class->size); |
| 1517 | d_off = obj_idx_to_offset(d_page, d_objidx, class->size); |
| 1518 | |
| 1519 | if (s_off + class->size > PAGE_SIZE) |
| 1520 | s_size = PAGE_SIZE - s_off; |
| 1521 | |
| 1522 | if (d_off + class->size > PAGE_SIZE) |
| 1523 | d_size = PAGE_SIZE - d_off; |
| 1524 | |
| 1525 | s_addr = kmap_atomic(s_page); |
| 1526 | d_addr = kmap_atomic(d_page); |
| 1527 | |
| 1528 | while (1) { |
| 1529 | size = min(s_size, d_size); |
| 1530 | memcpy(d_addr + d_off, s_addr + s_off, size); |
| 1531 | written += size; |
| 1532 | |
| 1533 | if (written == class->size) |
| 1534 | break; |
| 1535 | |
Sergey Senozhatsky | 495819e | 2015-04-15 16:16:15 -0700 | [diff] [blame] | 1536 | s_off += size; |
| 1537 | s_size -= size; |
| 1538 | d_off += size; |
| 1539 | d_size -= size; |
| 1540 | |
| 1541 | if (s_off >= PAGE_SIZE) { |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1542 | kunmap_atomic(d_addr); |
| 1543 | kunmap_atomic(s_addr); |
| 1544 | s_page = get_next_page(s_page); |
| 1545 | BUG_ON(!s_page); |
| 1546 | s_addr = kmap_atomic(s_page); |
| 1547 | d_addr = kmap_atomic(d_page); |
| 1548 | s_size = class->size - written; |
| 1549 | s_off = 0; |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1550 | } |
| 1551 | |
Sergey Senozhatsky | 495819e | 2015-04-15 16:16:15 -0700 | [diff] [blame] | 1552 | if (d_off >= PAGE_SIZE) { |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1553 | kunmap_atomic(d_addr); |
| 1554 | d_page = get_next_page(d_page); |
| 1555 | BUG_ON(!d_page); |
| 1556 | d_addr = kmap_atomic(d_page); |
| 1557 | d_size = class->size - written; |
| 1558 | d_off = 0; |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1559 | } |
| 1560 | } |
| 1561 | |
| 1562 | kunmap_atomic(d_addr); |
| 1563 | kunmap_atomic(s_addr); |
| 1564 | } |
| 1565 | |
| 1566 | /* |
| 1567 | * Find alloced object in zspage from index object and |
| 1568 | * return handle. |
| 1569 | */ |
| 1570 | static unsigned long find_alloced_obj(struct page *page, int index, |
| 1571 | struct size_class *class) |
| 1572 | { |
| 1573 | unsigned long head; |
| 1574 | int offset = 0; |
| 1575 | unsigned long handle = 0; |
| 1576 | void *addr = kmap_atomic(page); |
| 1577 | |
| 1578 | if (!is_first_page(page)) |
| 1579 | offset = page->index; |
| 1580 | offset += class->size * index; |
| 1581 | |
| 1582 | while (offset < PAGE_SIZE) { |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1583 | head = obj_to_head(class, page, addr + offset); |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1584 | if (head & OBJ_ALLOCATED_TAG) { |
| 1585 | handle = head & ~OBJ_ALLOCATED_TAG; |
| 1586 | if (trypin_tag(handle)) |
| 1587 | break; |
| 1588 | handle = 0; |
| 1589 | } |
| 1590 | |
| 1591 | offset += class->size; |
| 1592 | index++; |
| 1593 | } |
| 1594 | |
| 1595 | kunmap_atomic(addr); |
| 1596 | return handle; |
| 1597 | } |
| 1598 | |
| 1599 | struct zs_compact_control { |
| 1600 | /* Source page for migration which could be a subpage of zspage. */ |
| 1601 | struct page *s_page; |
| 1602 | /* Destination page for migration which should be a first page |
| 1603 | * of zspage. */ |
| 1604 | struct page *d_page; |
| 1605 | /* Starting object index within @s_page which used for live object |
| 1606 | * in the subpage. */ |
| 1607 | int index; |
| 1608 | /* how many of objects are migrated */ |
| 1609 | int nr_migrated; |
| 1610 | }; |
| 1611 | |
| 1612 | static int migrate_zspage(struct zs_pool *pool, struct size_class *class, |
| 1613 | struct zs_compact_control *cc) |
| 1614 | { |
| 1615 | unsigned long used_obj, free_obj; |
| 1616 | unsigned long handle; |
| 1617 | struct page *s_page = cc->s_page; |
| 1618 | struct page *d_page = cc->d_page; |
| 1619 | unsigned long index = cc->index; |
| 1620 | int nr_migrated = 0; |
| 1621 | int ret = 0; |
| 1622 | |
| 1623 | while (1) { |
| 1624 | handle = find_alloced_obj(s_page, index, class); |
| 1625 | if (!handle) { |
| 1626 | s_page = get_next_page(s_page); |
| 1627 | if (!s_page) |
| 1628 | break; |
| 1629 | index = 0; |
| 1630 | continue; |
| 1631 | } |
| 1632 | |
| 1633 | /* Stop if there is no more space */ |
| 1634 | if (zspage_full(d_page)) { |
| 1635 | unpin_tag(handle); |
| 1636 | ret = -ENOMEM; |
| 1637 | break; |
| 1638 | } |
| 1639 | |
| 1640 | used_obj = handle_to_obj(handle); |
| 1641 | free_obj = obj_malloc(d_page, class, handle); |
| 1642 | zs_object_copy(used_obj, free_obj, class); |
| 1643 | index++; |
| 1644 | record_obj(handle, free_obj); |
| 1645 | unpin_tag(handle); |
| 1646 | obj_free(pool, class, used_obj); |
| 1647 | nr_migrated++; |
| 1648 | } |
| 1649 | |
| 1650 | /* Remember last position in this iteration */ |
| 1651 | cc->s_page = s_page; |
| 1652 | cc->index = index; |
| 1653 | cc->nr_migrated = nr_migrated; |
| 1654 | |
| 1655 | return ret; |
| 1656 | } |
| 1657 | |
| 1658 | static struct page *alloc_target_page(struct size_class *class) |
| 1659 | { |
| 1660 | int i; |
| 1661 | struct page *page; |
| 1662 | |
| 1663 | for (i = 0; i < _ZS_NR_FULLNESS_GROUPS; i++) { |
| 1664 | page = class->fullness_list[i]; |
| 1665 | if (page) { |
| 1666 | remove_zspage(page, class, i); |
| 1667 | break; |
| 1668 | } |
| 1669 | } |
| 1670 | |
| 1671 | return page; |
| 1672 | } |
| 1673 | |
| 1674 | static void putback_zspage(struct zs_pool *pool, struct size_class *class, |
| 1675 | struct page *first_page) |
| 1676 | { |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1677 | enum fullness_group fullness; |
| 1678 | |
| 1679 | BUG_ON(!is_first_page(first_page)); |
| 1680 | |
Minchan Kim | 839373e | 2015-04-15 16:16:18 -0700 | [diff] [blame] | 1681 | fullness = get_fullness_group(first_page); |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1682 | insert_zspage(first_page, class, fullness); |
Minchan Kim | 839373e | 2015-04-15 16:16:18 -0700 | [diff] [blame] | 1683 | set_zspage_mapping(first_page, class->index, fullness); |
| 1684 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1685 | if (fullness == ZS_EMPTY) { |
| 1686 | zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage( |
| 1687 | class->size, class->pages_per_zspage)); |
| 1688 | atomic_long_sub(class->pages_per_zspage, |
| 1689 | &pool->pages_allocated); |
| 1690 | |
| 1691 | free_zspage(first_page); |
| 1692 | } |
| 1693 | } |
| 1694 | |
| 1695 | static struct page *isolate_source_page(struct size_class *class) |
| 1696 | { |
| 1697 | struct page *page; |
| 1698 | |
| 1699 | page = class->fullness_list[ZS_ALMOST_EMPTY]; |
| 1700 | if (page) |
| 1701 | remove_zspage(page, class, ZS_ALMOST_EMPTY); |
| 1702 | |
| 1703 | return page; |
| 1704 | } |
| 1705 | |
| 1706 | static unsigned long __zs_compact(struct zs_pool *pool, |
| 1707 | struct size_class *class) |
| 1708 | { |
| 1709 | int nr_to_migrate; |
| 1710 | struct zs_compact_control cc; |
| 1711 | struct page *src_page; |
| 1712 | struct page *dst_page = NULL; |
| 1713 | unsigned long nr_total_migrated = 0; |
| 1714 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1715 | spin_lock(&class->lock); |
| 1716 | while ((src_page = isolate_source_page(class))) { |
| 1717 | |
| 1718 | BUG_ON(!is_first_page(src_page)); |
| 1719 | |
| 1720 | /* The goal is to migrate all live objects in source page */ |
| 1721 | nr_to_migrate = src_page->inuse; |
| 1722 | cc.index = 0; |
| 1723 | cc.s_page = src_page; |
| 1724 | |
| 1725 | while ((dst_page = alloc_target_page(class))) { |
| 1726 | cc.d_page = dst_page; |
| 1727 | /* |
| 1728 | * If there is no more space in dst_page, try to |
| 1729 | * allocate another zspage. |
| 1730 | */ |
| 1731 | if (!migrate_zspage(pool, class, &cc)) |
| 1732 | break; |
| 1733 | |
| 1734 | putback_zspage(pool, class, dst_page); |
| 1735 | nr_total_migrated += cc.nr_migrated; |
| 1736 | nr_to_migrate -= cc.nr_migrated; |
| 1737 | } |
| 1738 | |
| 1739 | /* Stop if we couldn't find slot */ |
| 1740 | if (dst_page == NULL) |
| 1741 | break; |
| 1742 | |
| 1743 | putback_zspage(pool, class, dst_page); |
| 1744 | putback_zspage(pool, class, src_page); |
| 1745 | spin_unlock(&class->lock); |
| 1746 | nr_total_migrated += cc.nr_migrated; |
| 1747 | cond_resched(); |
| 1748 | spin_lock(&class->lock); |
| 1749 | } |
| 1750 | |
| 1751 | if (src_page) |
| 1752 | putback_zspage(pool, class, src_page); |
| 1753 | |
| 1754 | spin_unlock(&class->lock); |
| 1755 | |
| 1756 | return nr_total_migrated; |
| 1757 | } |
| 1758 | |
| 1759 | unsigned long zs_compact(struct zs_pool *pool) |
| 1760 | { |
| 1761 | int i; |
| 1762 | unsigned long nr_migrated = 0; |
| 1763 | struct size_class *class; |
| 1764 | |
| 1765 | for (i = zs_size_classes - 1; i >= 0; i--) { |
| 1766 | class = pool->size_class[i]; |
| 1767 | if (!class) |
| 1768 | continue; |
| 1769 | if (class->index != i) |
| 1770 | continue; |
| 1771 | nr_migrated += __zs_compact(pool, class); |
| 1772 | } |
| 1773 | |
Minchan Kim | 312fcae | 2015-04-15 16:15:30 -0700 | [diff] [blame] | 1774 | return nr_migrated; |
| 1775 | } |
| 1776 | EXPORT_SYMBOL_GPL(zs_compact); |
| 1777 | |
Davidlohr Bueso | 4bbc0bc | 2013-01-04 12:14:00 -0800 | [diff] [blame] | 1778 | /** |
| 1779 | * zs_create_pool - Creates an allocation pool to work from. |
Seth Jennings | 0d145a5 | 2013-01-30 09:36:52 -0600 | [diff] [blame] | 1780 | * @flags: allocation flags used to allocate pool metadata |
Davidlohr Bueso | 4bbc0bc | 2013-01-04 12:14:00 -0800 | [diff] [blame] | 1781 | * |
| 1782 | * This function must be called before anything when using |
| 1783 | * the zsmalloc allocator. |
| 1784 | * |
| 1785 | * On success, a pointer to the newly created pool is returned, |
| 1786 | * otherwise NULL. |
| 1787 | */ |
Ganesh Mahendran | 3eba0c6 | 2015-02-12 15:00:51 -0800 | [diff] [blame] | 1788 | struct zs_pool *zs_create_pool(char *name, gfp_t flags) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1789 | { |
Ganesh Mahendran | 1813665 | 2014-12-12 16:57:10 -0800 | [diff] [blame] | 1790 | int i; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1791 | struct zs_pool *pool; |
Ganesh Mahendran | df8b5bb | 2014-12-12 16:57:07 -0800 | [diff] [blame] | 1792 | struct size_class *prev_class = NULL; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1793 | |
Ganesh Mahendran | 1813665 | 2014-12-12 16:57:10 -0800 | [diff] [blame] | 1794 | pool = kzalloc(sizeof(*pool), GFP_KERNEL); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1795 | if (!pool) |
| 1796 | return NULL; |
| 1797 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1798 | pool->size_class = kcalloc(zs_size_classes, sizeof(struct size_class *), |
| 1799 | GFP_KERNEL); |
| 1800 | if (!pool->size_class) { |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1801 | kfree(pool); |
| 1802 | return NULL; |
| 1803 | } |
| 1804 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1805 | pool->name = kstrdup(name, GFP_KERNEL); |
| 1806 | if (!pool->name) |
| 1807 | goto err; |
| 1808 | |
| 1809 | if (create_handle_cache(pool)) |
| 1810 | goto err; |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1811 | |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1812 | /* |
| 1813 | * Iterate reversly, because, size of size_class that we want to use |
| 1814 | * for merging should be larger or equal to current size. |
| 1815 | */ |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1816 | for (i = zs_size_classes - 1; i >= 0; i--) { |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1817 | int size; |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1818 | int pages_per_zspage; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1819 | struct size_class *class; |
| 1820 | |
| 1821 | size = ZS_MIN_ALLOC_SIZE + i * ZS_SIZE_CLASS_DELTA; |
| 1822 | if (size > ZS_MAX_ALLOC_SIZE) |
| 1823 | size = ZS_MAX_ALLOC_SIZE; |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1824 | pages_per_zspage = get_pages_per_zspage(size); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1825 | |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1826 | /* |
| 1827 | * size_class is used for normal zsmalloc operation such |
| 1828 | * as alloc/free for that size. Although it is natural that we |
| 1829 | * have one size_class for each size, there is a chance that we |
| 1830 | * can get more memory utilization if we use one size_class for |
| 1831 | * many different sizes whose size_class have same |
| 1832 | * characteristics. So, we makes size_class point to |
| 1833 | * previous size_class if possible. |
| 1834 | */ |
Ganesh Mahendran | df8b5bb | 2014-12-12 16:57:07 -0800 | [diff] [blame] | 1835 | if (prev_class) { |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1836 | if (can_merge(prev_class, size, pages_per_zspage)) { |
| 1837 | pool->size_class[i] = prev_class; |
| 1838 | continue; |
| 1839 | } |
| 1840 | } |
| 1841 | |
| 1842 | class = kzalloc(sizeof(struct size_class), GFP_KERNEL); |
| 1843 | if (!class) |
| 1844 | goto err; |
| 1845 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1846 | class->size = size; |
| 1847 | class->index = i; |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1848 | class->pages_per_zspage = pages_per_zspage; |
Minchan Kim | 7b60a68 | 2015-04-15 16:15:39 -0700 | [diff] [blame] | 1849 | if (pages_per_zspage == 1 && |
| 1850 | get_maxobj_per_zspage(size, pages_per_zspage) == 1) |
| 1851 | class->huge = true; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1852 | spin_lock_init(&class->lock); |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1853 | pool->size_class[i] = class; |
Ganesh Mahendran | df8b5bb | 2014-12-12 16:57:07 -0800 | [diff] [blame] | 1854 | |
| 1855 | prev_class = class; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1856 | } |
| 1857 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1858 | pool->flags = flags; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1859 | |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1860 | if (zs_pool_stat_create(name, pool)) |
| 1861 | goto err; |
| 1862 | |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1863 | return pool; |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1864 | |
| 1865 | err: |
| 1866 | zs_destroy_pool(pool); |
| 1867 | return NULL; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1868 | } |
| 1869 | EXPORT_SYMBOL_GPL(zs_create_pool); |
| 1870 | |
| 1871 | void zs_destroy_pool(struct zs_pool *pool) |
| 1872 | { |
| 1873 | int i; |
| 1874 | |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1875 | zs_pool_stat_destroy(pool); |
| 1876 | |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1877 | for (i = 0; i < zs_size_classes; i++) { |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1878 | int fg; |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1879 | struct size_class *class = pool->size_class[i]; |
| 1880 | |
| 1881 | if (!class) |
| 1882 | continue; |
| 1883 | |
| 1884 | if (class->index != i) |
| 1885 | continue; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1886 | |
| 1887 | for (fg = 0; fg < _ZS_NR_FULLNESS_GROUPS; fg++) { |
| 1888 | if (class->fullness_list[fg]) { |
Marlies Ruck | 93ad5ab | 2013-05-15 16:56:49 -0400 | [diff] [blame] | 1889 | pr_info("Freeing non-empty class with size %db, fullness group %d\n", |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1890 | class->size, fg); |
| 1891 | } |
| 1892 | } |
Joonsoo Kim | 9eec4cd | 2014-12-12 16:56:44 -0800 | [diff] [blame] | 1893 | kfree(class); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1894 | } |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1895 | |
Minchan Kim | 2e40e16 | 2015-04-15 16:15:23 -0700 | [diff] [blame] | 1896 | destroy_handle_cache(pool); |
Mahendran Ganesh | 40f9fb8 | 2014-12-12 16:57:01 -0800 | [diff] [blame] | 1897 | kfree(pool->size_class); |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1898 | kfree(pool->name); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1899 | kfree(pool); |
| 1900 | } |
| 1901 | EXPORT_SYMBOL_GPL(zs_destroy_pool); |
| 1902 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1903 | static int __init zs_init(void) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1904 | { |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1905 | int ret = zs_register_cpu_notifier(); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1906 | |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1907 | if (ret) |
| 1908 | goto notifier_fail; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1909 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1910 | init_zs_size_classes(); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1911 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1912 | #ifdef CONFIG_ZPOOL |
| 1913 | zpool_register_driver(&zs_zpool_driver); |
| 1914 | #endif |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1915 | |
| 1916 | ret = zs_stat_init(); |
| 1917 | if (ret) { |
| 1918 | pr_err("zs stat initialization failed\n"); |
| 1919 | goto stat_fail; |
| 1920 | } |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1921 | return 0; |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1922 | |
| 1923 | stat_fail: |
| 1924 | #ifdef CONFIG_ZPOOL |
| 1925 | zpool_unregister_driver(&zs_zpool_driver); |
| 1926 | #endif |
| 1927 | notifier_fail: |
| 1928 | zs_unregister_cpu_notifier(); |
| 1929 | |
| 1930 | return ret; |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1931 | } |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1932 | |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1933 | static void __exit zs_exit(void) |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1934 | { |
Ganesh Mahendran | 66cdef6 | 2014-12-18 16:17:40 -0800 | [diff] [blame] | 1935 | #ifdef CONFIG_ZPOOL |
| 1936 | zpool_unregister_driver(&zs_zpool_driver); |
| 1937 | #endif |
| 1938 | zs_unregister_cpu_notifier(); |
Ganesh Mahendran | 0f050d9 | 2015-02-12 15:00:54 -0800 | [diff] [blame] | 1939 | |
| 1940 | zs_stat_exit(); |
Nitin Gupta | 61989a8 | 2012-01-09 16:51:56 -0600 | [diff] [blame] | 1941 | } |
Ben Hutchings | 069f101 | 2012-06-20 02:31:11 +0100 | [diff] [blame] | 1942 | |
| 1943 | module_init(zs_init); |
| 1944 | module_exit(zs_exit); |
| 1945 | |
| 1946 | MODULE_LICENSE("Dual BSD/GPL"); |
| 1947 | MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>"); |