Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1 | /* |
| 2 | * GPL HEADER START |
| 3 | * |
| 4 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 only, |
| 8 | * as published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * General Public License version 2 for more details (a copy is included |
| 14 | * in the LICENSE file that accompanied this code). |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * version 2 along with this program; If not, see |
Oleg Drokin | 6a5b99a | 2016-06-14 23:33:40 -0400 | [diff] [blame] | 18 | * http://www.gnu.org/licenses/gpl-2.0.html |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 19 | * |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 20 | * GPL HEADER END |
| 21 | */ |
| 22 | /* |
| 23 | * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. |
| 24 | * Use is subject to license terms. |
| 25 | * |
Andreas Dilger | 1dc563a | 2015-11-08 18:09:37 -0500 | [diff] [blame] | 26 | * Copyright (c) 2011, 2015, Intel Corporation. |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 27 | */ |
| 28 | /* |
| 29 | * This file is part of Lustre, http://www.lustre.org/ |
| 30 | * Lustre is a trademark of Sun Microsystems, Inc. |
| 31 | */ |
| 32 | |
| 33 | #ifndef __LUSTRE_LU_OBJECT_H |
| 34 | #define __LUSTRE_LU_OBJECT_H |
| 35 | |
| 36 | #include <stdarg.h> |
Greg Kroah-Hartman | 9fdaf8c | 2014-07-11 20:51:16 -0700 | [diff] [blame] | 37 | #include "../../include/linux/libcfs/libcfs.h" |
Greg Kroah-Hartman | 1accaad | 2014-07-11 21:34:24 -0700 | [diff] [blame] | 38 | #include "lustre/lustre_idl.h" |
| 39 | #include "lu_ref.h" |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 40 | |
| 41 | struct seq_file; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 42 | struct lustre_cfg; |
| 43 | struct lprocfs_stats; |
| 44 | |
| 45 | /** \defgroup lu lu |
| 46 | * lu_* data-types represent server-side entities shared by data and meta-data |
| 47 | * stacks. |
| 48 | * |
| 49 | * Design goals: |
| 50 | * |
| 51 | * -# support for layering. |
| 52 | * |
| 53 | * Server side object is split into layers, one per device in the |
| 54 | * corresponding device stack. Individual layer is represented by struct |
| 55 | * lu_object. Compound layered object --- by struct lu_object_header. Most |
| 56 | * interface functions take lu_object as an argument and operate on the |
| 57 | * whole compound object. This decision was made due to the following |
| 58 | * reasons: |
| 59 | * |
| 60 | * - it's envisaged that lu_object will be used much more often than |
| 61 | * lu_object_header; |
| 62 | * |
| 63 | * - we want lower (non-top) layers to be able to initiate operations |
| 64 | * on the whole object. |
| 65 | * |
| 66 | * Generic code supports layering more complex than simple stacking, e.g., |
| 67 | * it is possible that at some layer object "spawns" multiple sub-objects |
| 68 | * on the lower layer. |
| 69 | * |
| 70 | * -# fid-based identification. |
| 71 | * |
| 72 | * Compound object is uniquely identified by its fid. Objects are indexed |
| 73 | * by their fids (hash table is used for index). |
| 74 | * |
| 75 | * -# caching and life-cycle management. |
| 76 | * |
| 77 | * Object's life-time is controlled by reference counting. When reference |
| 78 | * count drops to 0, object is returned to cache. Cached objects still |
| 79 | * retain their identity (i.e., fid), and can be recovered from cache. |
| 80 | * |
| 81 | * Objects are kept in the global LRU list, and lu_site_purge() function |
| 82 | * can be used to reclaim given number of unused objects from the tail of |
| 83 | * the LRU. |
| 84 | * |
| 85 | * -# avoiding recursion. |
| 86 | * |
| 87 | * Generic code tries to replace recursion through layers by iterations |
| 88 | * where possible. Additionally to the end of reducing stack consumption, |
| 89 | * data, when practically possible, are allocated through lu_context_key |
| 90 | * interface rather than on stack. |
| 91 | * @{ |
| 92 | */ |
| 93 | |
| 94 | struct lu_site; |
| 95 | struct lu_object; |
| 96 | struct lu_device; |
| 97 | struct lu_object_header; |
| 98 | struct lu_context; |
| 99 | struct lu_env; |
| 100 | |
| 101 | /** |
| 102 | * Operations common for data and meta-data devices. |
| 103 | */ |
| 104 | struct lu_device_operations { |
| 105 | /** |
| 106 | * Allocate object for the given device (without lower-layer |
| 107 | * parts). This is called by lu_object_operations::loo_object_init() |
| 108 | * from the parent layer, and should setup at least lu_object::lo_dev |
| 109 | * and lu_object::lo_ops fields of resulting lu_object. |
| 110 | * |
| 111 | * Object creation protocol. |
| 112 | * |
| 113 | * Due to design goal of avoiding recursion, object creation (see |
| 114 | * lu_object_alloc()) is somewhat involved: |
| 115 | * |
| 116 | * - first, lu_device_operations::ldo_object_alloc() method of the |
| 117 | * top-level device in the stack is called. It should allocate top |
| 118 | * level object (including lu_object_header), but without any |
| 119 | * lower-layer sub-object(s). |
| 120 | * |
| 121 | * - then lu_object_alloc() sets fid in the header of newly created |
| 122 | * object. |
| 123 | * |
| 124 | * - then lu_object_operations::loo_object_init() is called. It has |
| 125 | * to allocate lower-layer object(s). To do this, |
| 126 | * lu_object_operations::loo_object_init() calls ldo_object_alloc() |
| 127 | * of the lower-layer device(s). |
| 128 | * |
| 129 | * - for all new objects allocated by |
| 130 | * lu_object_operations::loo_object_init() (and inserted into object |
| 131 | * stack), lu_object_operations::loo_object_init() is called again |
| 132 | * repeatedly, until no new objects are created. |
| 133 | * |
| 134 | * \post ergo(!IS_ERR(result), result->lo_dev == d && |
| 135 | * result->lo_ops != NULL); |
| 136 | */ |
| 137 | struct lu_object *(*ldo_object_alloc)(const struct lu_env *env, |
| 138 | const struct lu_object_header *h, |
| 139 | struct lu_device *d); |
| 140 | /** |
| 141 | * process config specific for device. |
| 142 | */ |
| 143 | int (*ldo_process_config)(const struct lu_env *env, |
| 144 | struct lu_device *, struct lustre_cfg *); |
| 145 | int (*ldo_recovery_complete)(const struct lu_env *, |
| 146 | struct lu_device *); |
| 147 | |
| 148 | /** |
| 149 | * initialize local objects for device. this method called after layer has |
| 150 | * been initialized (after LCFG_SETUP stage) and before it starts serving |
| 151 | * user requests. |
| 152 | */ |
| 153 | |
| 154 | int (*ldo_prepare)(const struct lu_env *, |
| 155 | struct lu_device *parent, |
| 156 | struct lu_device *dev); |
| 157 | |
| 158 | }; |
| 159 | |
| 160 | /** |
| 161 | * For lu_object_conf flags |
| 162 | */ |
Oleg Drokin | 426652f | 2016-02-24 21:59:47 -0500 | [diff] [blame] | 163 | enum loc_flags { |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 164 | /* This is a new object to be allocated, or the file |
Oleg Drokin | c56e256 | 2016-02-24 22:00:25 -0500 | [diff] [blame] | 165 | * corresponding to the object does not exists. |
| 166 | */ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 167 | LOC_F_NEW = 0x00000001, |
Oleg Drokin | 426652f | 2016-02-24 21:59:47 -0500 | [diff] [blame] | 168 | }; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 169 | |
| 170 | /** |
| 171 | * Object configuration, describing particulars of object being created. On |
| 172 | * server this is not used, as server objects are full identified by fid. On |
| 173 | * client configuration contains struct lustre_md. |
| 174 | */ |
| 175 | struct lu_object_conf { |
| 176 | /** |
| 177 | * Some hints for obj find and alloc. |
| 178 | */ |
Oleg Drokin | 426652f | 2016-02-24 21:59:47 -0500 | [diff] [blame] | 179 | enum loc_flags loc_flags; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 180 | }; |
| 181 | |
| 182 | /** |
| 183 | * Type of "printer" function used by lu_object_operations::loo_object_print() |
| 184 | * method. |
| 185 | * |
| 186 | * Printer function is needed to provide some flexibility in (semi-)debugging |
| 187 | * output: possible implementations: printk, CDEBUG, sysfs/seq_file |
| 188 | */ |
| 189 | typedef int (*lu_printer_t)(const struct lu_env *env, |
| 190 | void *cookie, const char *format, ...) |
Mario J. Rugiero | 70837c1 | 2015-03-10 12:02:03 -0300 | [diff] [blame] | 191 | __printf(3, 4); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 192 | |
| 193 | /** |
| 194 | * Operations specific for particular lu_object. |
| 195 | */ |
| 196 | struct lu_object_operations { |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 197 | /** |
| 198 | * Allocate lower-layer parts of the object by calling |
| 199 | * lu_device_operations::ldo_object_alloc() of the corresponding |
| 200 | * underlying device. |
| 201 | * |
| 202 | * This method is called once for each object inserted into object |
| 203 | * stack. It's responsibility of this method to insert lower-layer |
| 204 | * object(s) it create into appropriate places of object stack. |
| 205 | */ |
| 206 | int (*loo_object_init)(const struct lu_env *env, |
| 207 | struct lu_object *o, |
| 208 | const struct lu_object_conf *conf); |
| 209 | /** |
| 210 | * Called (in top-to-bottom order) during object allocation after all |
| 211 | * layers were allocated and initialized. Can be used to perform |
| 212 | * initialization depending on lower layers. |
| 213 | */ |
| 214 | int (*loo_object_start)(const struct lu_env *env, |
| 215 | struct lu_object *o); |
| 216 | /** |
| 217 | * Called before lu_object_operations::loo_object_free() to signal |
| 218 | * that object is being destroyed. Dual to |
| 219 | * lu_object_operations::loo_object_init(). |
| 220 | */ |
| 221 | void (*loo_object_delete)(const struct lu_env *env, |
| 222 | struct lu_object *o); |
| 223 | /** |
| 224 | * Dual to lu_device_operations::ldo_object_alloc(). Called when |
| 225 | * object is removed from memory. |
| 226 | */ |
| 227 | void (*loo_object_free)(const struct lu_env *env, |
| 228 | struct lu_object *o); |
| 229 | /** |
| 230 | * Called when last active reference to the object is released (and |
| 231 | * object returns to the cache). This method is optional. |
| 232 | */ |
| 233 | void (*loo_object_release)(const struct lu_env *env, |
| 234 | struct lu_object *o); |
| 235 | /** |
| 236 | * Optional debugging helper. Print given object. |
| 237 | */ |
| 238 | int (*loo_object_print)(const struct lu_env *env, void *cookie, |
| 239 | lu_printer_t p, const struct lu_object *o); |
| 240 | /** |
| 241 | * Optional debugging method. Returns true iff method is internally |
| 242 | * consistent. |
| 243 | */ |
| 244 | int (*loo_object_invariant)(const struct lu_object *o); |
| 245 | }; |
| 246 | |
| 247 | /** |
| 248 | * Type of lu_device. |
| 249 | */ |
| 250 | struct lu_device_type; |
| 251 | |
| 252 | /** |
| 253 | * Device: a layer in the server side abstraction stacking. |
| 254 | */ |
| 255 | struct lu_device { |
| 256 | /** |
| 257 | * reference count. This is incremented, in particular, on each object |
| 258 | * created at this layer. |
| 259 | * |
| 260 | * \todo XXX which means that atomic_t is probably too small. |
| 261 | */ |
| 262 | atomic_t ld_ref; |
| 263 | /** |
| 264 | * Pointer to device type. Never modified once set. |
| 265 | */ |
| 266 | struct lu_device_type *ld_type; |
| 267 | /** |
| 268 | * Operation vector for this device. |
| 269 | */ |
| 270 | const struct lu_device_operations *ld_ops; |
| 271 | /** |
| 272 | * Stack this device belongs to. |
| 273 | */ |
| 274 | struct lu_site *ld_site; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 275 | |
| 276 | /** \todo XXX: temporary back pointer into obd. */ |
| 277 | struct obd_device *ld_obd; |
| 278 | /** |
| 279 | * A list of references to this object, for debugging. |
| 280 | */ |
| 281 | struct lu_ref ld_reference; |
| 282 | /** |
| 283 | * Link the device to the site. |
| 284 | **/ |
| 285 | struct list_head ld_linkage; |
| 286 | }; |
| 287 | |
| 288 | struct lu_device_type_operations; |
| 289 | |
| 290 | /** |
| 291 | * Tag bits for device type. They are used to distinguish certain groups of |
| 292 | * device types. |
| 293 | */ |
| 294 | enum lu_device_tag { |
| 295 | /** this is meta-data device */ |
| 296 | LU_DEVICE_MD = (1 << 0), |
| 297 | /** this is data device */ |
| 298 | LU_DEVICE_DT = (1 << 1), |
| 299 | /** data device in the client stack */ |
| 300 | LU_DEVICE_CL = (1 << 2) |
| 301 | }; |
| 302 | |
| 303 | /** |
| 304 | * Type of device. |
| 305 | */ |
| 306 | struct lu_device_type { |
| 307 | /** |
| 308 | * Tag bits. Taken from enum lu_device_tag. Never modified once set. |
| 309 | */ |
| 310 | __u32 ldt_tags; |
| 311 | /** |
| 312 | * Name of this class. Unique system-wide. Never modified once set. |
| 313 | */ |
| 314 | char *ldt_name; |
| 315 | /** |
| 316 | * Operations for this type. |
| 317 | */ |
| 318 | const struct lu_device_type_operations *ldt_ops; |
| 319 | /** |
| 320 | * \todo XXX: temporary pointer to associated obd_type. |
| 321 | */ |
| 322 | struct obd_type *ldt_obd_type; |
| 323 | /** |
| 324 | * \todo XXX: temporary: context tags used by obd_*() calls. |
| 325 | */ |
| 326 | __u32 ldt_ctx_tags; |
| 327 | /** |
| 328 | * Number of existing device type instances. |
| 329 | */ |
| 330 | unsigned ldt_device_nr; |
| 331 | /** |
| 332 | * Linkage into a global list of all device types. |
| 333 | * |
| 334 | * \see lu_device_types. |
| 335 | */ |
| 336 | struct list_head ldt_linkage; |
| 337 | }; |
| 338 | |
| 339 | /** |
| 340 | * Operations on a device type. |
| 341 | */ |
| 342 | struct lu_device_type_operations { |
| 343 | /** |
| 344 | * Allocate new device. |
| 345 | */ |
| 346 | struct lu_device *(*ldto_device_alloc)(const struct lu_env *env, |
| 347 | struct lu_device_type *t, |
| 348 | struct lustre_cfg *lcfg); |
| 349 | /** |
| 350 | * Free device. Dual to |
| 351 | * lu_device_type_operations::ldto_device_alloc(). Returns pointer to |
| 352 | * the next device in the stack. |
| 353 | */ |
| 354 | struct lu_device *(*ldto_device_free)(const struct lu_env *, |
| 355 | struct lu_device *); |
| 356 | |
| 357 | /** |
| 358 | * Initialize the devices after allocation |
| 359 | */ |
| 360 | int (*ldto_device_init)(const struct lu_env *env, |
| 361 | struct lu_device *, const char *, |
| 362 | struct lu_device *); |
| 363 | /** |
| 364 | * Finalize device. Dual to |
| 365 | * lu_device_type_operations::ldto_device_init(). Returns pointer to |
| 366 | * the next device in the stack. |
| 367 | */ |
| 368 | struct lu_device *(*ldto_device_fini)(const struct lu_env *env, |
| 369 | struct lu_device *); |
| 370 | /** |
| 371 | * Initialize device type. This is called on module load. |
| 372 | */ |
| 373 | int (*ldto_init)(struct lu_device_type *t); |
| 374 | /** |
| 375 | * Finalize device type. Dual to |
| 376 | * lu_device_type_operations::ldto_init(). Called on module unload. |
| 377 | */ |
| 378 | void (*ldto_fini)(struct lu_device_type *t); |
| 379 | /** |
| 380 | * Called when the first device is created. |
| 381 | */ |
| 382 | void (*ldto_start)(struct lu_device_type *t); |
| 383 | /** |
| 384 | * Called when number of devices drops to 0. |
| 385 | */ |
| 386 | void (*ldto_stop)(struct lu_device_type *t); |
| 387 | }; |
| 388 | |
| 389 | static inline int lu_device_is_md(const struct lu_device *d) |
| 390 | { |
Oleg Drokin | d2a1398 | 2016-02-16 00:46:52 -0500 | [diff] [blame] | 391 | return ergo(d, d->ld_type->ldt_tags & LU_DEVICE_MD); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 392 | } |
| 393 | |
| 394 | /** |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 395 | * Common object attributes. |
| 396 | */ |
| 397 | struct lu_attr { |
| 398 | /** size in bytes */ |
| 399 | __u64 la_size; |
| 400 | /** modification time in seconds since Epoch */ |
Oleg Drokin | 21aef7d | 2014-08-15 12:55:56 -0400 | [diff] [blame] | 401 | s64 la_mtime; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 402 | /** access time in seconds since Epoch */ |
Oleg Drokin | 21aef7d | 2014-08-15 12:55:56 -0400 | [diff] [blame] | 403 | s64 la_atime; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 404 | /** change time in seconds since Epoch */ |
Oleg Drokin | 21aef7d | 2014-08-15 12:55:56 -0400 | [diff] [blame] | 405 | s64 la_ctime; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 406 | /** 512-byte blocks allocated to object */ |
| 407 | __u64 la_blocks; |
| 408 | /** permission bits and file type */ |
| 409 | __u32 la_mode; |
| 410 | /** owner id */ |
| 411 | __u32 la_uid; |
| 412 | /** group id */ |
| 413 | __u32 la_gid; |
| 414 | /** object flags */ |
| 415 | __u32 la_flags; |
| 416 | /** number of persistent references to this object */ |
| 417 | __u32 la_nlink; |
| 418 | /** blk bits of the object*/ |
| 419 | __u32 la_blkbits; |
| 420 | /** blk size of the object*/ |
| 421 | __u32 la_blksize; |
| 422 | /** real device */ |
| 423 | __u32 la_rdev; |
| 424 | /** |
| 425 | * valid bits |
| 426 | * |
| 427 | * \see enum la_valid |
| 428 | */ |
| 429 | __u64 la_valid; |
| 430 | }; |
| 431 | |
| 432 | /** Bit-mask of valid attributes */ |
| 433 | enum la_valid { |
| 434 | LA_ATIME = 1 << 0, |
| 435 | LA_MTIME = 1 << 1, |
| 436 | LA_CTIME = 1 << 2, |
| 437 | LA_SIZE = 1 << 3, |
| 438 | LA_MODE = 1 << 4, |
| 439 | LA_UID = 1 << 5, |
| 440 | LA_GID = 1 << 6, |
| 441 | LA_BLOCKS = 1 << 7, |
| 442 | LA_TYPE = 1 << 8, |
| 443 | LA_FLAGS = 1 << 9, |
| 444 | LA_NLINK = 1 << 10, |
| 445 | LA_RDEV = 1 << 11, |
| 446 | LA_BLKSIZE = 1 << 12, |
| 447 | LA_KILL_SUID = 1 << 13, |
| 448 | LA_KILL_SGID = 1 << 14, |
| 449 | }; |
| 450 | |
| 451 | /** |
| 452 | * Layer in the layered object. |
| 453 | */ |
| 454 | struct lu_object { |
| 455 | /** |
| 456 | * Header for this object. |
| 457 | */ |
| 458 | struct lu_object_header *lo_header; |
| 459 | /** |
| 460 | * Device for this layer. |
| 461 | */ |
| 462 | struct lu_device *lo_dev; |
| 463 | /** |
| 464 | * Operations for this object. |
| 465 | */ |
| 466 | const struct lu_object_operations *lo_ops; |
| 467 | /** |
| 468 | * Linkage into list of all layers. |
| 469 | */ |
| 470 | struct list_head lo_linkage; |
| 471 | /** |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 472 | * Link to the device, for debugging. |
| 473 | */ |
John L. Hammond | 631abc6 | 2013-07-25 01:17:30 +0800 | [diff] [blame] | 474 | struct lu_ref_link lo_dev_ref; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 475 | }; |
| 476 | |
| 477 | enum lu_object_header_flags { |
| 478 | /** |
| 479 | * Don't keep this object in cache. Object will be destroyed as soon |
| 480 | * as last reference to it is released. This flag cannot be cleared |
| 481 | * once set. |
| 482 | */ |
| 483 | LU_OBJECT_HEARD_BANSHEE = 0, |
| 484 | /** |
| 485 | * Mark this object has already been taken out of cache. |
| 486 | */ |
Fan Yong | 8b88bca | 2015-12-23 12:32:12 -0500 | [diff] [blame] | 487 | LU_OBJECT_UNHASHED = 1, |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 488 | }; |
| 489 | |
| 490 | enum lu_object_header_attr { |
| 491 | LOHA_EXISTS = 1 << 0, |
| 492 | LOHA_REMOTE = 1 << 1, |
| 493 | /** |
| 494 | * UNIX file type is stored in S_IFMT bits. |
| 495 | */ |
| 496 | LOHA_FT_START = 001 << 12, /**< S_IFIFO */ |
| 497 | LOHA_FT_END = 017 << 12, /**< S_IFMT */ |
| 498 | }; |
| 499 | |
| 500 | /** |
| 501 | * "Compound" object, consisting of multiple layers. |
| 502 | * |
| 503 | * Compound object with given fid is unique with given lu_site. |
| 504 | * |
| 505 | * Note, that object does *not* necessary correspond to the real object in the |
| 506 | * persistent storage: object is an anchor for locking and method calling, so |
| 507 | * it is created for things like not-yet-existing child created by mkdir or |
| 508 | * create calls. lu_object_operations::loo_exists() can be used to check |
| 509 | * whether object is backed by persistent storage entity. |
| 510 | */ |
| 511 | struct lu_object_header { |
| 512 | /** |
Andreas Dilger | a700f97 | 2014-04-27 13:06:51 -0400 | [diff] [blame] | 513 | * Fid, uniquely identifying this object. |
| 514 | */ |
| 515 | struct lu_fid loh_fid; |
| 516 | /** |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 517 | * Object flags from enum lu_object_header_flags. Set and checked |
| 518 | * atomically. |
| 519 | */ |
| 520 | unsigned long loh_flags; |
| 521 | /** |
| 522 | * Object reference count. Protected by lu_site::ls_guard. |
| 523 | */ |
| 524 | atomic_t loh_ref; |
| 525 | /** |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 526 | * Common object attributes, cached for efficiency. From enum |
| 527 | * lu_object_header_attr. |
| 528 | */ |
| 529 | __u32 loh_attr; |
| 530 | /** |
| 531 | * Linkage into per-site hash table. Protected by lu_site::ls_guard. |
| 532 | */ |
| 533 | struct hlist_node loh_hash; |
| 534 | /** |
| 535 | * Linkage into per-site LRU list. Protected by lu_site::ls_guard. |
| 536 | */ |
| 537 | struct list_head loh_lru; |
| 538 | /** |
| 539 | * Linkage into list of layers. Never modified once set (except lately |
| 540 | * during object destruction). No locking is necessary. |
| 541 | */ |
| 542 | struct list_head loh_layers; |
| 543 | /** |
| 544 | * A list of references to this object, for debugging. |
| 545 | */ |
| 546 | struct lu_ref loh_reference; |
| 547 | }; |
| 548 | |
| 549 | struct fld; |
| 550 | |
| 551 | struct lu_site_bkt_data { |
| 552 | /** |
Frank Zago | 6e580ab | 2015-09-14 18:41:18 -0400 | [diff] [blame] | 553 | * number of object in this bucket on the lsb_lru list. |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 554 | */ |
Frank Zago | 6e580ab | 2015-09-14 18:41:18 -0400 | [diff] [blame] | 555 | long lsb_lru_len; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 556 | /** |
| 557 | * LRU list, updated on each access to object. Protected by |
| 558 | * bucket lock of lu_site::ls_obj_hash. |
| 559 | * |
| 560 | * "Cold" end of LRU is lu_site::ls_lru.next. Accessed object are |
| 561 | * moved to the lu_site::ls_lru.prev (this is due to the non-existence |
| 562 | * of list_for_each_entry_safe_reverse()). |
| 563 | */ |
| 564 | struct list_head lsb_lru; |
| 565 | /** |
| 566 | * Wait-queue signaled when an object in this site is ultimately |
| 567 | * destroyed (lu_object_free()). It is used by lu_object_find() to |
| 568 | * wait before re-trying when object in the process of destruction is |
| 569 | * found in the hash table. |
| 570 | * |
| 571 | * \see htable_lookup(). |
| 572 | */ |
| 573 | wait_queue_head_t lsb_marche_funebre; |
| 574 | }; |
| 575 | |
| 576 | enum { |
| 577 | LU_SS_CREATED = 0, |
| 578 | LU_SS_CACHE_HIT, |
| 579 | LU_SS_CACHE_MISS, |
| 580 | LU_SS_CACHE_RACE, |
| 581 | LU_SS_CACHE_DEATH_RACE, |
| 582 | LU_SS_LRU_PURGED, |
Ann Koehler | a0b8803 | 2015-09-14 18:41:30 -0400 | [diff] [blame] | 583 | LU_SS_LRU_LEN, /* # of objects in lsb_lru lists */ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 584 | LU_SS_LAST_STAT |
| 585 | }; |
| 586 | |
| 587 | /** |
| 588 | * lu_site is a "compartment" within which objects are unique, and LRU |
| 589 | * discipline is maintained. |
| 590 | * |
| 591 | * lu_site exists so that multiple layered stacks can co-exist in the same |
| 592 | * address space. |
| 593 | * |
| 594 | * lu_site has the same relation to lu_device as lu_object_header to |
| 595 | * lu_object. |
| 596 | */ |
| 597 | struct lu_site { |
| 598 | /** |
| 599 | * objects hash table |
| 600 | */ |
Lisa Nguyen | 6da6eab | 2013-10-21 18:16:26 -0700 | [diff] [blame] | 601 | struct cfs_hash *ls_obj_hash; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 602 | /** |
| 603 | * index of bucket on hash table while purging |
| 604 | */ |
| 605 | int ls_purge_start; |
| 606 | /** |
| 607 | * Top-level device for this stack. |
| 608 | */ |
| 609 | struct lu_device *ls_top_dev; |
| 610 | /** |
| 611 | * Bottom-level device for this stack |
| 612 | */ |
| 613 | struct lu_device *ls_bottom_dev; |
| 614 | /** |
| 615 | * Linkage into global list of sites. |
| 616 | */ |
| 617 | struct list_head ls_linkage; |
| 618 | /** |
| 619 | * List for lu device for this site, protected |
| 620 | * by ls_ld_lock. |
| 621 | **/ |
| 622 | struct list_head ls_ld_linkage; |
| 623 | spinlock_t ls_ld_lock; |
| 624 | |
| 625 | /** |
| 626 | * lu_site stats |
| 627 | */ |
| 628 | struct lprocfs_stats *ls_stats; |
| 629 | /** |
| 630 | * XXX: a hack! fld has to find md_site via site, remove when possible |
| 631 | */ |
| 632 | struct seq_server_site *ld_seq_site; |
| 633 | }; |
| 634 | |
| 635 | static inline struct lu_site_bkt_data * |
| 636 | lu_site_bkt_from_fid(struct lu_site *site, struct lu_fid *fid) |
| 637 | { |
Lisa Nguyen | 6ea510c | 2013-10-21 18:16:05 -0700 | [diff] [blame] | 638 | struct cfs_hash_bd bd; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 639 | |
| 640 | cfs_hash_bd_get(site->ls_obj_hash, fid, &bd); |
| 641 | return cfs_hash_bd_extra_get(site->ls_obj_hash, &bd); |
| 642 | } |
| 643 | |
Liu Xuezhao | 56f4c5a | 2013-07-23 00:06:44 +0800 | [diff] [blame] | 644 | static inline struct seq_server_site *lu_site2seq(const struct lu_site *s) |
| 645 | { |
| 646 | return s->ld_seq_site; |
| 647 | } |
| 648 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 649 | /** \name ctors |
| 650 | * Constructors/destructors. |
| 651 | * @{ |
| 652 | */ |
| 653 | |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 654 | int lu_site_init(struct lu_site *s, struct lu_device *d); |
| 655 | void lu_site_fini(struct lu_site *s); |
| 656 | int lu_site_init_finish(struct lu_site *s); |
| 657 | void lu_stack_fini(const struct lu_env *env, struct lu_device *top); |
| 658 | void lu_device_get(struct lu_device *d); |
| 659 | void lu_device_put(struct lu_device *d); |
| 660 | int lu_device_init(struct lu_device *d, struct lu_device_type *t); |
| 661 | void lu_device_fini(struct lu_device *d); |
| 662 | int lu_object_header_init(struct lu_object_header *h); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 663 | void lu_object_header_fini(struct lu_object_header *h); |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 664 | int lu_object_init(struct lu_object *o, |
| 665 | struct lu_object_header *h, struct lu_device *d); |
| 666 | void lu_object_fini(struct lu_object *o); |
| 667 | void lu_object_add_top(struct lu_object_header *h, struct lu_object *o); |
| 668 | void lu_object_add(struct lu_object *before, struct lu_object *o); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 669 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 670 | /** |
| 671 | * Helpers to initialize and finalize device types. |
| 672 | */ |
| 673 | |
| 674 | int lu_device_type_init(struct lu_device_type *ldt); |
| 675 | void lu_device_type_fini(struct lu_device_type *ldt); |
| 676 | void lu_types_stop(void); |
| 677 | |
| 678 | /** @} ctors */ |
| 679 | |
| 680 | /** \name caching |
| 681 | * Caching and reference counting. |
| 682 | * @{ |
| 683 | */ |
| 684 | |
| 685 | /** |
| 686 | * Acquire additional reference to the given object. This function is used to |
| 687 | * attain additional reference. To acquire initial reference use |
| 688 | * lu_object_find(). |
| 689 | */ |
| 690 | static inline void lu_object_get(struct lu_object *o) |
| 691 | { |
| 692 | LASSERT(atomic_read(&o->lo_header->loh_ref) > 0); |
| 693 | atomic_inc(&o->lo_header->loh_ref); |
| 694 | } |
| 695 | |
| 696 | /** |
| 697 | * Return true of object will not be cached after last reference to it is |
| 698 | * released. |
| 699 | */ |
| 700 | static inline int lu_object_is_dying(const struct lu_object_header *h) |
| 701 | { |
| 702 | return test_bit(LU_OBJECT_HEARD_BANSHEE, &h->loh_flags); |
| 703 | } |
| 704 | |
| 705 | void lu_object_put(const struct lu_env *env, struct lu_object *o); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 706 | void lu_object_unhash(const struct lu_env *env, struct lu_object *o); |
| 707 | |
| 708 | int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr); |
| 709 | |
| 710 | void lu_site_print(const struct lu_env *env, struct lu_site *s, void *cookie, |
| 711 | lu_printer_t printer); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 712 | struct lu_object *lu_object_find_at(const struct lu_env *env, |
| 713 | struct lu_device *dev, |
| 714 | const struct lu_fid *f, |
| 715 | const struct lu_object_conf *conf); |
| 716 | struct lu_object *lu_object_find_slice(const struct lu_env *env, |
| 717 | struct lu_device *dev, |
| 718 | const struct lu_fid *f, |
| 719 | const struct lu_object_conf *conf); |
| 720 | /** @} caching */ |
| 721 | |
| 722 | /** \name helpers |
| 723 | * Helpers. |
| 724 | * @{ |
| 725 | */ |
| 726 | |
| 727 | /** |
| 728 | * First (topmost) sub-object of given compound object |
| 729 | */ |
| 730 | static inline struct lu_object *lu_object_top(struct lu_object_header *h) |
| 731 | { |
| 732 | LASSERT(!list_empty(&h->loh_layers)); |
| 733 | return container_of0(h->loh_layers.next, struct lu_object, lo_linkage); |
| 734 | } |
| 735 | |
| 736 | /** |
| 737 | * Next sub-object in the layering |
| 738 | */ |
| 739 | static inline struct lu_object *lu_object_next(const struct lu_object *o) |
| 740 | { |
| 741 | return container_of0(o->lo_linkage.next, struct lu_object, lo_linkage); |
| 742 | } |
| 743 | |
| 744 | /** |
| 745 | * Pointer to the fid of this object. |
| 746 | */ |
| 747 | static inline const struct lu_fid *lu_object_fid(const struct lu_object *o) |
| 748 | { |
| 749 | return &o->lo_header->loh_fid; |
| 750 | } |
| 751 | |
| 752 | /** |
| 753 | * return device operations vector for this object |
| 754 | */ |
Valdis Kletnieks | b8947b3 | 2015-12-22 19:36:49 -0500 | [diff] [blame] | 755 | static inline const struct lu_device_operations * |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 756 | lu_object_ops(const struct lu_object *o) |
| 757 | { |
| 758 | return o->lo_dev->ld_ops; |
| 759 | } |
| 760 | |
| 761 | /** |
| 762 | * Given a compound object, find its slice, corresponding to the device type |
| 763 | * \a dtype. |
| 764 | */ |
| 765 | struct lu_object *lu_object_locate(struct lu_object_header *h, |
| 766 | const struct lu_device_type *dtype); |
| 767 | |
| 768 | /** |
| 769 | * Printer function emitting messages through libcfs_debug_msg(). |
| 770 | */ |
| 771 | int lu_cdebug_printer(const struct lu_env *env, |
| 772 | void *cookie, const char *format, ...); |
| 773 | |
| 774 | /** |
| 775 | * Print object description followed by a user-supplied message. |
| 776 | */ |
| 777 | #define LU_OBJECT_DEBUG(mask, env, object, format, ...) \ |
| 778 | do { \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 779 | if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) { \ |
Oleg Drokin | 83e8d02 | 2016-04-28 12:07:31 -0400 | [diff] [blame] | 780 | LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, NULL); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 781 | lu_object_print(env, &msgdata, lu_cdebug_printer, object);\ |
Bob Glossman | d55d5e8 | 2016-06-20 16:55:37 -0400 | [diff] [blame] | 782 | CDEBUG(mask, format "\n", ## __VA_ARGS__); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 783 | } \ |
| 784 | } while (0) |
| 785 | |
| 786 | /** |
| 787 | * Print short object description followed by a user-supplied message. |
| 788 | */ |
| 789 | #define LU_OBJECT_HEADER(mask, env, object, format, ...) \ |
| 790 | do { \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 791 | if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) { \ |
Oleg Drokin | 83e8d02 | 2016-04-28 12:07:31 -0400 | [diff] [blame] | 792 | LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, NULL); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 793 | lu_object_header_print(env, &msgdata, lu_cdebug_printer,\ |
| 794 | (object)->lo_header); \ |
| 795 | lu_cdebug_printer(env, &msgdata, "\n"); \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 796 | CDEBUG(mask, format, ## __VA_ARGS__); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 797 | } \ |
| 798 | } while (0) |
| 799 | |
| 800 | void lu_object_print (const struct lu_env *env, void *cookie, |
| 801 | lu_printer_t printer, const struct lu_object *o); |
| 802 | void lu_object_header_print(const struct lu_env *env, void *cookie, |
| 803 | lu_printer_t printer, |
| 804 | const struct lu_object_header *hdr); |
| 805 | |
| 806 | /** |
| 807 | * Check object consistency. |
| 808 | */ |
| 809 | int lu_object_invariant(const struct lu_object *o); |
| 810 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 811 | /** |
| 812 | * Check whether object exists, no matter on local or remote storage. |
| 813 | * Note: LOHA_EXISTS will be set once some one created the object, |
| 814 | * and it does not needs to be committed to storage. |
| 815 | */ |
| 816 | #define lu_object_exists(o) ((o)->lo_header->loh_attr & LOHA_EXISTS) |
| 817 | |
| 818 | /** |
| 819 | * Check whether object on the remote storage. |
| 820 | */ |
| 821 | #define lu_object_remote(o) unlikely((o)->lo_header->loh_attr & LOHA_REMOTE) |
| 822 | |
| 823 | static inline int lu_object_assert_exists(const struct lu_object *o) |
| 824 | { |
| 825 | return lu_object_exists(o); |
| 826 | } |
| 827 | |
| 828 | static inline int lu_object_assert_not_exists(const struct lu_object *o) |
| 829 | { |
| 830 | return !lu_object_exists(o); |
| 831 | } |
| 832 | |
| 833 | /** |
| 834 | * Attr of this object. |
| 835 | */ |
| 836 | static inline __u32 lu_object_attr(const struct lu_object *o) |
| 837 | { |
| 838 | LASSERT(lu_object_exists(o) != 0); |
| 839 | return o->lo_header->loh_attr; |
| 840 | } |
| 841 | |
John L. Hammond | 631abc6 | 2013-07-25 01:17:30 +0800 | [diff] [blame] | 842 | static inline void lu_object_ref_add(struct lu_object *o, |
| 843 | const char *scope, |
| 844 | const void *source) |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 845 | { |
John L. Hammond | 631abc6 | 2013-07-25 01:17:30 +0800 | [diff] [blame] | 846 | lu_ref_add(&o->lo_header->loh_reference, scope, source); |
| 847 | } |
| 848 | |
| 849 | static inline void lu_object_ref_add_at(struct lu_object *o, |
| 850 | struct lu_ref_link *link, |
| 851 | const char *scope, |
| 852 | const void *source) |
| 853 | { |
| 854 | lu_ref_add_at(&o->lo_header->loh_reference, link, scope, source); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 855 | } |
| 856 | |
| 857 | static inline void lu_object_ref_del(struct lu_object *o, |
| 858 | const char *scope, const void *source) |
| 859 | { |
| 860 | lu_ref_del(&o->lo_header->loh_reference, scope, source); |
| 861 | } |
| 862 | |
| 863 | static inline void lu_object_ref_del_at(struct lu_object *o, |
| 864 | struct lu_ref_link *link, |
| 865 | const char *scope, const void *source) |
| 866 | { |
| 867 | lu_ref_del_at(&o->lo_header->loh_reference, link, scope, source); |
| 868 | } |
| 869 | |
| 870 | /** input params, should be filled out by mdt */ |
| 871 | struct lu_rdpg { |
| 872 | /** hash */ |
| 873 | __u64 rp_hash; |
| 874 | /** count in bytes */ |
| 875 | unsigned int rp_count; |
| 876 | /** number of pages */ |
| 877 | unsigned int rp_npages; |
| 878 | /** requested attr */ |
| 879 | __u32 rp_attrs; |
| 880 | /** pointers to pages */ |
| 881 | struct page **rp_pages; |
| 882 | }; |
| 883 | |
| 884 | enum lu_xattr_flags { |
| 885 | LU_XATTR_REPLACE = (1 << 0), |
| 886 | LU_XATTR_CREATE = (1 << 1) |
| 887 | }; |
| 888 | |
| 889 | /** @} helpers */ |
| 890 | |
| 891 | /** \name lu_context |
Oleg Drokin | c56e256 | 2016-02-24 22:00:25 -0500 | [diff] [blame] | 892 | * @{ |
| 893 | */ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 894 | |
| 895 | /** For lu_context health-checks */ |
| 896 | enum lu_context_state { |
| 897 | LCS_INITIALIZED = 1, |
| 898 | LCS_ENTERED, |
| 899 | LCS_LEFT, |
| 900 | LCS_FINALIZED |
| 901 | }; |
| 902 | |
| 903 | /** |
| 904 | * lu_context. Execution context for lu_object methods. Currently associated |
| 905 | * with thread. |
| 906 | * |
| 907 | * All lu_object methods, except device and device type methods (called during |
| 908 | * system initialization and shutdown) are executed "within" some |
| 909 | * lu_context. This means, that pointer to some "current" lu_context is passed |
| 910 | * as an argument to all methods. |
| 911 | * |
| 912 | * All service ptlrpc threads create lu_context as part of their |
| 913 | * initialization. It is possible to create "stand-alone" context for other |
| 914 | * execution environments (like system calls). |
| 915 | * |
| 916 | * lu_object methods mainly use lu_context through lu_context_key interface |
| 917 | * that allows each layer to associate arbitrary pieces of data with each |
| 918 | * context (see pthread_key_create(3) for similar interface). |
| 919 | * |
| 920 | * On a client, lu_context is bound to a thread, see cl_env_get(). |
| 921 | * |
| 922 | * \see lu_context_key |
| 923 | */ |
| 924 | struct lu_context { |
| 925 | /** |
| 926 | * lu_context is used on the client side too. Yet we don't want to |
| 927 | * allocate values of server-side keys for the client contexts and |
| 928 | * vice versa. |
| 929 | * |
| 930 | * To achieve this, set of tags in introduced. Contexts and keys are |
| 931 | * marked with tags. Key value are created only for context whose set |
| 932 | * of tags has non-empty intersection with one for key. Tags are taken |
| 933 | * from enum lu_context_tag. |
| 934 | */ |
| 935 | __u32 lc_tags; |
| 936 | enum lu_context_state lc_state; |
| 937 | /** |
| 938 | * Pointer to the home service thread. NULL for other execution |
| 939 | * contexts. |
| 940 | */ |
| 941 | struct ptlrpc_thread *lc_thread; |
| 942 | /** |
| 943 | * Pointer to an array with key values. Internal implementation |
| 944 | * detail. |
| 945 | */ |
| 946 | void **lc_value; |
| 947 | /** |
| 948 | * Linkage into a list of all remembered contexts. Only |
| 949 | * `non-transient' contexts, i.e., ones created for service threads |
| 950 | * are placed here. |
| 951 | */ |
| 952 | struct list_head lc_remember; |
| 953 | /** |
| 954 | * Version counter used to skip calls to lu_context_refill() when no |
| 955 | * keys were registered. |
| 956 | */ |
| 957 | unsigned lc_version; |
| 958 | /** |
| 959 | * Debugging cookie. |
| 960 | */ |
| 961 | unsigned lc_cookie; |
| 962 | }; |
| 963 | |
| 964 | /** |
| 965 | * lu_context_key interface. Similar to pthread_key. |
| 966 | */ |
| 967 | |
| 968 | enum lu_context_tag { |
| 969 | /** |
| 970 | * Thread on md server |
| 971 | */ |
| 972 | LCT_MD_THREAD = 1 << 0, |
| 973 | /** |
| 974 | * Thread on dt server |
| 975 | */ |
| 976 | LCT_DT_THREAD = 1 << 1, |
| 977 | /** |
| 978 | * Context for transaction handle |
| 979 | */ |
| 980 | LCT_TX_HANDLE = 1 << 2, |
| 981 | /** |
| 982 | * Thread on client |
| 983 | */ |
| 984 | LCT_CL_THREAD = 1 << 3, |
| 985 | /** |
| 986 | * A per-request session on a server, and a per-system-call session on |
| 987 | * a client. |
| 988 | */ |
| 989 | LCT_SESSION = 1 << 4, |
| 990 | /** |
| 991 | * A per-request data on OSP device |
| 992 | */ |
| 993 | LCT_OSP_THREAD = 1 << 5, |
| 994 | /** |
| 995 | * MGS device thread |
| 996 | */ |
| 997 | LCT_MG_THREAD = 1 << 6, |
| 998 | /** |
| 999 | * Context for local operations |
| 1000 | */ |
| 1001 | LCT_LOCAL = 1 << 7, |
| 1002 | /** |
Wang Di | 7f937be | 2016-04-27 18:20:55 -0400 | [diff] [blame] | 1003 | * session for server thread |
| 1004 | **/ |
| 1005 | LCT_SERVER_SESSION = BIT(8), |
| 1006 | /** |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1007 | * Set when at least one of keys, having values in this context has |
| 1008 | * non-NULL lu_context_key::lct_exit() method. This is used to |
| 1009 | * optimize lu_context_exit() call. |
| 1010 | */ |
| 1011 | LCT_HAS_EXIT = 1 << 28, |
| 1012 | /** |
| 1013 | * Don't add references for modules creating key values in that context. |
| 1014 | * This is only for contexts used internally by lu_object framework. |
| 1015 | */ |
| 1016 | LCT_NOREF = 1 << 29, |
| 1017 | /** |
| 1018 | * Key is being prepared for retiring, don't create new values for it. |
| 1019 | */ |
| 1020 | LCT_QUIESCENT = 1 << 30, |
| 1021 | /** |
| 1022 | * Context should be remembered. |
| 1023 | */ |
| 1024 | LCT_REMEMBER = 1 << 31, |
| 1025 | /** |
| 1026 | * Contexts usable in cache shrinker thread. |
| 1027 | */ |
| 1028 | LCT_SHRINKER = LCT_MD_THREAD|LCT_DT_THREAD|LCT_CL_THREAD|LCT_NOREF |
| 1029 | }; |
| 1030 | |
| 1031 | /** |
| 1032 | * Key. Represents per-context value slot. |
| 1033 | * |
| 1034 | * Keys are usually registered when module owning the key is initialized, and |
| 1035 | * de-registered when module is unloaded. Once key is registered, all new |
| 1036 | * contexts with matching tags, will get key value. "Old" contexts, already |
| 1037 | * initialized at the time of key registration, can be forced to get key value |
| 1038 | * by calling lu_context_refill(). |
| 1039 | * |
| 1040 | * Every key value is counted in lu_context_key::lct_used and acquires a |
| 1041 | * reference on an owning module. This means, that all key values have to be |
| 1042 | * destroyed before module can be unloaded. This is usually achieved by |
| 1043 | * stopping threads started by the module, that created contexts in their |
| 1044 | * entry functions. Situation is complicated by the threads shared by multiple |
| 1045 | * modules, like ptlrpcd daemon on a client. To work around this problem, |
| 1046 | * contexts, created in such threads, are `remembered' (see |
| 1047 | * LCT_REMEMBER)---i.e., added into a global list. When module is preparing |
| 1048 | * for unloading it does the following: |
| 1049 | * |
| 1050 | * - marks its keys as `quiescent' (lu_context_tag::LCT_QUIESCENT) |
| 1051 | * preventing new key values from being allocated in the new contexts, |
| 1052 | * and |
| 1053 | * |
| 1054 | * - scans a list of remembered contexts, destroying values of module |
| 1055 | * keys, thus releasing references to the module. |
| 1056 | * |
| 1057 | * This is done by lu_context_key_quiesce(). If module is re-activated |
| 1058 | * before key has been de-registered, lu_context_key_revive() call clears |
| 1059 | * `quiescent' marker. |
| 1060 | * |
| 1061 | * lu_context code doesn't provide any internal synchronization for these |
| 1062 | * activities---it's assumed that startup (including threads start-up) and |
| 1063 | * shutdown are serialized by some external means. |
| 1064 | * |
| 1065 | * \see lu_context |
| 1066 | */ |
| 1067 | struct lu_context_key { |
| 1068 | /** |
| 1069 | * Set of tags for which values of this key are to be instantiated. |
| 1070 | */ |
| 1071 | __u32 lct_tags; |
| 1072 | /** |
| 1073 | * Value constructor. This is called when new value is created for a |
| 1074 | * context. Returns pointer to new value of error pointer. |
| 1075 | */ |
| 1076 | void *(*lct_init)(const struct lu_context *ctx, |
| 1077 | struct lu_context_key *key); |
| 1078 | /** |
| 1079 | * Value destructor. Called when context with previously allocated |
| 1080 | * value of this slot is destroyed. \a data is a value that was returned |
| 1081 | * by a matching call to lu_context_key::lct_init(). |
| 1082 | */ |
| 1083 | void (*lct_fini)(const struct lu_context *ctx, |
| 1084 | struct lu_context_key *key, void *data); |
| 1085 | /** |
| 1086 | * Optional method called on lu_context_exit() for all allocated |
| 1087 | * keys. Can be used by debugging code checking that locks are |
| 1088 | * released, etc. |
| 1089 | */ |
| 1090 | void (*lct_exit)(const struct lu_context *ctx, |
| 1091 | struct lu_context_key *key, void *data); |
| 1092 | /** |
| 1093 | * Internal implementation detail: index within lu_context::lc_value[] |
| 1094 | * reserved for this key. |
| 1095 | */ |
| 1096 | int lct_index; |
| 1097 | /** |
| 1098 | * Internal implementation detail: number of values created for this |
| 1099 | * key. |
| 1100 | */ |
| 1101 | atomic_t lct_used; |
| 1102 | /** |
| 1103 | * Internal implementation detail: module for this key. |
| 1104 | */ |
Greg Kroah-Hartman | c34d9cd | 2013-08-04 07:48:41 +0800 | [diff] [blame] | 1105 | struct module *lct_owner; |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1106 | /** |
| 1107 | * References to this key. For debugging. |
| 1108 | */ |
| 1109 | struct lu_ref lct_reference; |
| 1110 | }; |
| 1111 | |
| 1112 | #define LU_KEY_INIT(mod, type) \ |
Greg Donald | 9c234f6 | 2014-10-02 18:10:23 -0500 | [diff] [blame] | 1113 | static void *mod##_key_init(const struct lu_context *ctx, \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1114 | struct lu_context_key *key) \ |
| 1115 | { \ |
| 1116 | type *value; \ |
| 1117 | \ |
Greg Kroah-Hartman | 5f47992 | 2016-04-11 09:30:50 -0700 | [diff] [blame] | 1118 | CLASSERT(PAGE_SIZE >= sizeof(*value)); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1119 | \ |
Oleg Drokin | fca5ba8 | 2015-09-16 12:26:55 -0400 | [diff] [blame] | 1120 | value = kzalloc(sizeof(*value), GFP_NOFS); \ |
Oleg Drokin | d2a1398 | 2016-02-16 00:46:52 -0500 | [diff] [blame] | 1121 | if (!value) \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1122 | value = ERR_PTR(-ENOMEM); \ |
| 1123 | \ |
| 1124 | return value; \ |
| 1125 | } \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 1126 | struct __##mod##__dummy_init {; } /* semicolon catcher */ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1127 | |
| 1128 | #define LU_KEY_FINI(mod, type) \ |
| 1129 | static void mod##_key_fini(const struct lu_context *ctx, \ |
Greg Donald | 9c234f6 | 2014-10-02 18:10:23 -0500 | [diff] [blame] | 1130 | struct lu_context_key *key, void *data) \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1131 | { \ |
| 1132 | type *info = data; \ |
| 1133 | \ |
Oleg Drokin | fca5ba8 | 2015-09-16 12:26:55 -0400 | [diff] [blame] | 1134 | kfree(info); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1135 | } \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 1136 | struct __##mod##__dummy_fini {; } /* semicolon catcher */ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1137 | |
| 1138 | #define LU_KEY_INIT_FINI(mod, type) \ |
Greg Donald | 1d8cb70 | 2014-08-25 20:07:19 -0500 | [diff] [blame] | 1139 | LU_KEY_INIT(mod, type); \ |
| 1140 | LU_KEY_FINI(mod, type) |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1141 | |
| 1142 | #define LU_CONTEXT_KEY_DEFINE(mod, tags) \ |
| 1143 | struct lu_context_key mod##_thread_key = { \ |
| 1144 | .lct_tags = tags, \ |
| 1145 | .lct_init = mod##_key_init, \ |
| 1146 | .lct_fini = mod##_key_fini \ |
| 1147 | } |
| 1148 | |
| 1149 | #define LU_CONTEXT_KEY_INIT(key) \ |
| 1150 | do { \ |
| 1151 | (key)->lct_owner = THIS_MODULE; \ |
| 1152 | } while (0) |
| 1153 | |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 1154 | int lu_context_key_register(struct lu_context_key *key); |
| 1155 | void lu_context_key_degister(struct lu_context_key *key); |
| 1156 | void *lu_context_key_get(const struct lu_context *ctx, |
| 1157 | const struct lu_context_key *key); |
| 1158 | void lu_context_key_quiesce(struct lu_context_key *key); |
| 1159 | void lu_context_key_revive(struct lu_context_key *key); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1160 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1161 | /* |
| 1162 | * LU_KEY_INIT_GENERIC() has to be a macro to correctly determine an |
| 1163 | * owning module. |
| 1164 | */ |
| 1165 | |
| 1166 | #define LU_KEY_INIT_GENERIC(mod) \ |
| 1167 | static void mod##_key_init_generic(struct lu_context_key *k, ...) \ |
| 1168 | { \ |
| 1169 | struct lu_context_key *key = k; \ |
| 1170 | va_list args; \ |
| 1171 | \ |
| 1172 | va_start(args, k); \ |
| 1173 | do { \ |
| 1174 | LU_CONTEXT_KEY_INIT(key); \ |
| 1175 | key = va_arg(args, struct lu_context_key *); \ |
Oleg Drokin | d2a1398 | 2016-02-16 00:46:52 -0500 | [diff] [blame] | 1176 | } while (key); \ |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1177 | va_end(args); \ |
| 1178 | } |
| 1179 | |
| 1180 | #define LU_TYPE_INIT(mod, ...) \ |
| 1181 | LU_KEY_INIT_GENERIC(mod) \ |
| 1182 | static int mod##_type_init(struct lu_device_type *t) \ |
| 1183 | { \ |
| 1184 | mod##_key_init_generic(__VA_ARGS__, NULL); \ |
| 1185 | return lu_context_key_register_many(__VA_ARGS__, NULL); \ |
| 1186 | } \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 1187 | struct __##mod##_dummy_type_init {; } |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1188 | |
| 1189 | #define LU_TYPE_FINI(mod, ...) \ |
| 1190 | static void mod##_type_fini(struct lu_device_type *t) \ |
| 1191 | { \ |
| 1192 | lu_context_key_degister_many(__VA_ARGS__, NULL); \ |
| 1193 | } \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 1194 | struct __##mod##_dummy_type_fini {; } |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1195 | |
| 1196 | #define LU_TYPE_START(mod, ...) \ |
| 1197 | static void mod##_type_start(struct lu_device_type *t) \ |
| 1198 | { \ |
| 1199 | lu_context_key_revive_many(__VA_ARGS__, NULL); \ |
| 1200 | } \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 1201 | struct __##mod##_dummy_type_start {; } |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1202 | |
| 1203 | #define LU_TYPE_STOP(mod, ...) \ |
| 1204 | static void mod##_type_stop(struct lu_device_type *t) \ |
| 1205 | { \ |
| 1206 | lu_context_key_quiesce_many(__VA_ARGS__, NULL); \ |
| 1207 | } \ |
Mike Rapoport | b2952d6 | 2015-09-03 11:49:13 +0300 | [diff] [blame] | 1208 | struct __##mod##_dummy_type_stop {; } |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1209 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1210 | #define LU_TYPE_INIT_FINI(mod, ...) \ |
| 1211 | LU_TYPE_INIT(mod, __VA_ARGS__); \ |
| 1212 | LU_TYPE_FINI(mod, __VA_ARGS__); \ |
| 1213 | LU_TYPE_START(mod, __VA_ARGS__); \ |
| 1214 | LU_TYPE_STOP(mod, __VA_ARGS__) |
| 1215 | |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 1216 | int lu_context_init(struct lu_context *ctx, __u32 tags); |
| 1217 | void lu_context_fini(struct lu_context *ctx); |
| 1218 | void lu_context_enter(struct lu_context *ctx); |
| 1219 | void lu_context_exit(struct lu_context *ctx); |
| 1220 | int lu_context_refill(struct lu_context *ctx); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1221 | |
| 1222 | /* |
| 1223 | * Helper functions to operate on multiple keys. These are used by the default |
| 1224 | * device type operations, defined by LU_TYPE_INIT_FINI(). |
| 1225 | */ |
| 1226 | |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 1227 | int lu_context_key_register_many(struct lu_context_key *k, ...); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1228 | void lu_context_key_degister_many(struct lu_context_key *k, ...); |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 1229 | void lu_context_key_revive_many(struct lu_context_key *k, ...); |
| 1230 | void lu_context_key_quiesce_many(struct lu_context_key *k, ...); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1231 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1232 | /** |
| 1233 | * Environment. |
| 1234 | */ |
| 1235 | struct lu_env { |
| 1236 | /** |
| 1237 | * "Local" context, used to store data instead of stack. |
| 1238 | */ |
| 1239 | struct lu_context le_ctx; |
| 1240 | /** |
| 1241 | * "Session" context for per-request data. |
| 1242 | */ |
| 1243 | struct lu_context *le_ses; |
| 1244 | }; |
| 1245 | |
Oleg Drokin | e9570b4 | 2016-03-30 19:49:05 -0400 | [diff] [blame] | 1246 | int lu_env_init(struct lu_env *env, __u32 tags); |
| 1247 | void lu_env_fini(struct lu_env *env); |
| 1248 | int lu_env_refill(struct lu_env *env); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1249 | |
| 1250 | /** @} lu_context */ |
| 1251 | |
| 1252 | /** |
| 1253 | * Output site statistical counters into a buffer. Suitable for |
| 1254 | * ll_rd_*()-style functions. |
| 1255 | */ |
Peng Tao | 73bb1da | 2013-05-29 21:40:55 +0800 | [diff] [blame] | 1256 | int lu_site_stats_print(const struct lu_site *s, struct seq_file *m); |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1257 | |
| 1258 | /** |
| 1259 | * Common name structure to be passed around for various name related methods. |
| 1260 | */ |
| 1261 | struct lu_name { |
| 1262 | const char *ln_name; |
| 1263 | int ln_namelen; |
| 1264 | }; |
| 1265 | |
| 1266 | /** |
| 1267 | * Common buffer structure to be passed around for various xattr_{s,g}et() |
| 1268 | * methods. |
| 1269 | */ |
| 1270 | struct lu_buf { |
| 1271 | void *lb_buf; |
| 1272 | ssize_t lb_len; |
| 1273 | }; |
| 1274 | |
| 1275 | #define DLUBUF "(%p %zu)" |
| 1276 | #define PLUBUF(buf) (buf)->lb_buf, (buf)->lb_len |
| 1277 | /** |
| 1278 | * One-time initializers, called at obdclass module initialization, not |
| 1279 | * exported. |
| 1280 | */ |
| 1281 | |
| 1282 | /** |
| 1283 | * Initialization of global lu_* data. |
| 1284 | */ |
| 1285 | int lu_global_init(void); |
| 1286 | |
| 1287 | /** |
| 1288 | * Dual to lu_global_init(). |
| 1289 | */ |
| 1290 | void lu_global_fini(void); |
| 1291 | |
| 1292 | struct lu_kmem_descr { |
| 1293 | struct kmem_cache **ckd_cache; |
| 1294 | const char *ckd_name; |
| 1295 | const size_t ckd_size; |
| 1296 | }; |
| 1297 | |
| 1298 | int lu_kmem_init(struct lu_kmem_descr *caches); |
| 1299 | void lu_kmem_fini(struct lu_kmem_descr *caches); |
| 1300 | |
Peng Tao | d7e09d0 | 2013-05-02 16:46:55 +0800 | [diff] [blame] | 1301 | /** @} lu */ |
| 1302 | #endif /* __LUSTRE_LU_OBJECT_H */ |