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37 #ifndef __LUSTRE_LU_OBJECT_H
38 #define __LUSTRE_LU_OBJECT_H
45 #include <lustre/lustre_idl.h>
47 #include <libcfs/libcfs.h>
52 struct proc_dir_entry;
57 * lu_* data-types represent server-side entities shared by data and meta-data
62 * -# support for layering.
64 * Server side object is split into layers, one per device in the
65 * corresponding device stack. Individual layer is represented by struct
66 * lu_object. Compound layered object --- by struct lu_object_header. Most
67 * interface functions take lu_object as an argument and operate on the
68 * whole compound object. This decision was made due to the following
71 * - it's envisaged that lu_object will be used much more often than
74 * - we want lower (non-top) layers to be able to initiate operations
75 * on the whole object.
77 * Generic code supports layering more complex than simple stacking, e.g.,
78 * it is possible that at some layer object "spawns" multiple sub-objects
81 * -# fid-based identification.
83 * Compound object is uniquely identified by its fid. Objects are indexed
84 * by their fids (hash table is used for index).
86 * -# caching and life-cycle management.
88 * Object's life-time is controlled by reference counting. When reference
89 * count drops to 0, object is returned to cache. Cached objects still
90 * retain their identity (i.e., fid), and can be recovered from cache.
92 * Objects are kept in the global LRU list, and lu_site_purge() function
93 * can be used to reclaim given number of unused objects from the tail of
96 * -# avoiding recursion.
98 * Generic code tries to replace recursion through layers by iterations
99 * where possible. Additionally to the end of reducing stack consumption,
100 * data, when practically possible, are allocated through lu_context_key
101 * interface rather than on stack.
108 struct lu_object_header;
113 * Operations common for data and meta-data devices.
115 struct lu_device_operations {
117 * Allocate object for the given device (without lower-layer
118 * parts). This is called by lu_object_operations::loo_object_init()
119 * from the parent layer, and should setup at least lu_object::lo_dev
120 * and lu_object::lo_ops fields of resulting lu_object.
122 * Object creation protocol.
124 * Due to design goal of avoiding recursion, object creation (see
125 * lu_object_alloc()) is somewhat involved:
127 * - first, lu_device_operations::ldo_object_alloc() method of the
128 * top-level device in the stack is called. It should allocate top
129 * level object (including lu_object_header), but without any
130 * lower-layer sub-object(s).
132 * - then lu_object_alloc() sets fid in the header of newly created
135 * - then lu_object_operations::loo_object_init() is called. It has
136 * to allocate lower-layer object(s). To do this,
137 * lu_object_operations::loo_object_init() calls ldo_object_alloc()
138 * of the lower-layer device(s).
140 * - for all new objects allocated by
141 * lu_object_operations::loo_object_init() (and inserted into object
142 * stack), lu_object_operations::loo_object_init() is called again
143 * repeatedly, until no new objects are created.
145 * \post ergo(!IS_ERR(result), result->lo_dev == d &&
146 * result->lo_ops != NULL);
148 struct lu_object *(*ldo_object_alloc)(const struct lu_env *env,
149 const struct lu_object_header *h,
150 struct lu_device *d);
152 * process config specific for device.
154 int (*ldo_process_config)(const struct lu_env *env,
155 struct lu_device *, struct lustre_cfg *);
156 int (*ldo_recovery_complete)(const struct lu_env *,
162 * Object configuration, describing particulars of object being created. On
163 * server this is not used, as server objects are full identified by fid. On
164 * client configuration contains struct lustre_md.
166 struct lu_object_conf {
170 * Type of "printer" function used by lu_object_operations::loo_object_print()
173 * Printer function is needed to provide some flexibility in (semi-)debugging
174 * output: possible implementations: printk, CDEBUG, sysfs/seq_file
176 typedef int (*lu_printer_t)(const struct lu_env *env,
177 void *cookie, const char *format, ...)
178 __attribute__ ((format (printf, 3, 4)));
181 * Operations specific for particular lu_object.
183 struct lu_object_operations {
186 * Allocate lower-layer parts of the object by calling
187 * lu_device_operations::ldo_object_alloc() of the corresponding
190 * This method is called once for each object inserted into object
191 * stack. It's responsibility of this method to insert lower-layer
192 * object(s) it create into appropriate places of object stack.
194 int (*loo_object_init)(const struct lu_env *env,
196 const struct lu_object_conf *conf);
198 * Called (in top-to-bottom order) during object allocation after all
199 * layers were allocated and initialized. Can be used to perform
200 * initialization depending on lower layers.
202 int (*loo_object_start)(const struct lu_env *env,
203 struct lu_object *o);
205 * Called before lu_object_operations::loo_object_free() to signal
206 * that object is being destroyed. Dual to
207 * lu_object_operations::loo_object_init().
209 void (*loo_object_delete)(const struct lu_env *env,
210 struct lu_object *o);
212 * Dual to lu_device_operations::ldo_object_alloc(). Called when
213 * object is removed from memory.
215 void (*loo_object_free)(const struct lu_env *env,
216 struct lu_object *o);
218 * Called when last active reference to the object is released (and
219 * object returns to the cache). This method is optional.
221 void (*loo_object_release)(const struct lu_env *env,
222 struct lu_object *o);
224 * Optional debugging helper. Print given object.
226 int (*loo_object_print)(const struct lu_env *env, void *cookie,
227 lu_printer_t p, const struct lu_object *o);
229 * Optional debugging method. Returns true iff method is internally
232 int (*loo_object_invariant)(const struct lu_object *o);
238 struct lu_device_type;
241 * Device: a layer in the server side abstraction stacking.
245 * reference count. This is incremented, in particular, on each object
246 * created at this layer.
248 * \todo XXX which means that atomic_t is probably too small.
252 * Pointer to device type. Never modified once set.
254 struct lu_device_type *ld_type;
256 * Operation vector for this device.
258 const struct lu_device_operations *ld_ops;
260 * Stack this device belongs to.
262 struct lu_site *ld_site;
263 struct proc_dir_entry *ld_proc_entry;
265 /** \todo XXX: temporary back pointer into obd. */
266 struct obd_device *ld_obd;
268 * A list of references to this object, for debugging.
270 struct lu_ref ld_reference;
273 struct lu_device_type_operations;
276 * Tag bits for device type. They are used to distinguish certain groups of
280 /** this is meta-data device */
281 LU_DEVICE_MD = (1 << 0),
282 /** this is data device */
283 LU_DEVICE_DT = (1 << 1),
284 /** data device in the client stack */
285 LU_DEVICE_CL = (1 << 2)
291 struct lu_device_type {
293 * Tag bits. Taken from enum lu_device_tag. Never modified once set.
297 * Name of this class. Unique system-wide. Never modified once set.
301 * Operations for this type.
303 const struct lu_device_type_operations *ldt_ops;
305 * \todo XXX: temporary pointer to associated obd_type.
307 struct obd_type *ldt_obd_type;
309 * \todo XXX: temporary: context tags used by obd_*() calls.
313 * Number of existing device type instances.
315 unsigned ldt_device_nr;
317 * Linkage into a global list of all device types.
319 * \see lu_device_types.
321 struct list_head ldt_linkage;
325 * Operations on a device type.
327 struct lu_device_type_operations {
329 * Allocate new device.
331 struct lu_device *(*ldto_device_alloc)(const struct lu_env *env,
332 struct lu_device_type *t,
333 struct lustre_cfg *lcfg);
335 * Free device. Dual to
336 * lu_device_type_operations::ldto_device_alloc(). Returns pointer to
337 * the next device in the stack.
339 struct lu_device *(*ldto_device_free)(const struct lu_env *,
343 * Initialize the devices after allocation
345 int (*ldto_device_init)(const struct lu_env *env,
346 struct lu_device *, const char *,
349 * Finalize device. Dual to
350 * lu_device_type_operations::ldto_device_init(). Returns pointer to
351 * the next device in the stack.
353 struct lu_device *(*ldto_device_fini)(const struct lu_env *env,
356 * Initialize device type. This is called on module load.
358 int (*ldto_init)(struct lu_device_type *t);
360 * Finalize device type. Dual to
361 * lu_device_type_operations::ldto_init(). Called on module unload.
363 void (*ldto_fini)(struct lu_device_type *t);
365 * Called when the first device is created.
367 void (*ldto_start)(struct lu_device_type *t);
369 * Called when number of devices drops to 0.
371 void (*ldto_stop)(struct lu_device_type *t);
375 * Flags for the object layers.
377 enum lu_object_flags {
379 * this flags is set if lu_object_operations::loo_object_init() has
380 * been called for this layer. Used by lu_object_alloc().
382 LU_OBJECT_ALLOCATED = (1 << 0)
386 * Common object attributes.
391 /** modification time in seconds since Epoch */
393 /** access time in seconds since Epoch */
395 /** change time in seconds since Epoch */
397 /** 512-byte blocks allocated to object */
399 /** permission bits and file type */
407 /** number of persistent references to this object */
409 /** blk bits of the object*/
411 /** blk size of the object*/
423 /** Bit-mask of valid attributes */
437 LA_BLKSIZE = 1 << 12,
441 * Layer in the layered object.
445 * Header for this object.
447 struct lu_object_header *lo_header;
449 * Device for this layer.
451 struct lu_device *lo_dev;
453 * Operations for this object.
455 const struct lu_object_operations *lo_ops;
457 * Linkage into list of all layers.
459 struct list_head lo_linkage;
461 * Depth. Top level layer depth is 0.
465 * Flags from enum lu_object_flags.
467 unsigned long lo_flags;
469 * Link to the device, for debugging.
471 struct lu_ref_link *lo_dev_ref;
474 enum lu_object_header_flags {
476 * Don't keep this object in cache. Object will be destroyed as soon
477 * as last reference to it is released. This flag cannot be cleared
480 LU_OBJECT_HEARD_BANSHEE = 0
483 enum lu_object_header_attr {
484 LOHA_EXISTS = 1 << 0,
485 LOHA_REMOTE = 1 << 1,
487 * UNIX file type is stored in S_IFMT bits.
489 LOHA_FT_START = 1 << 12, /* S_IFIFO */
490 LOHA_FT_END = 1 << 15, /* S_IFREG */
494 * "Compound" object, consisting of multiple layers.
496 * Compound object with given fid is unique with given lu_site.
498 * Note, that object does *not* necessary correspond to the real object in the
499 * persistent storage: object is an anchor for locking and method calling, so
500 * it is created for things like not-yet-existing child created by mkdir or
501 * create calls. lu_object_operations::loo_exists() can be used to check
502 * whether object is backed by persistent storage entity.
504 struct lu_object_header {
506 * Object flags from enum lu_object_header_flags. Set and checked
509 unsigned long loh_flags;
511 * Object reference count. Protected by lu_site::ls_guard.
515 * Fid, uniquely identifying this object.
517 struct lu_fid loh_fid;
519 * Common object attributes, cached for efficiency. From enum
520 * lu_object_header_attr.
524 * Linkage into per-site hash table. Protected by lu_site::ls_guard.
526 struct hlist_node loh_hash;
528 * Linkage into per-site LRU list. Protected by lu_site::ls_guard.
530 struct list_head loh_lru;
532 * Linkage into list of layers. Never modified once set (except lately
533 * during object destruction). No locking is necessary.
535 struct list_head loh_layers;
537 * A list of references to this object, for debugging.
539 struct lu_ref loh_reference;
545 * lu_site is a "compartment" within which objects are unique, and LRU
546 * discipline is maintained.
548 * lu_site exists so that multiple layered stacks can co-exist in the same
551 * lu_site has the same relation to lu_device as lu_object_header to
560 * - lu_site::ls_hash hash table (and its linkages in objects);
562 * - lu_site::ls_lru list (and its linkages in objects);
564 * - 0/1 transitions of object lu_object_header::loh_ref
571 * Hash-table where objects are indexed by fid.
573 struct hlist_head *ls_hash;
575 * Bit-mask for hash-table size.
579 * Order of hash-table.
583 * Number of buckets in the hash-table.
588 * LRU list, updated on each access to object. Protected by
591 * "Cold" end of LRU is lu_site::ls_lru.next. Accessed object are
592 * moved to the lu_site::ls_lru.prev (this is due to the non-existence
593 * of list_for_each_entry_safe_reverse()).
595 struct list_head ls_lru;
597 * Total number of objects in this site. Protected by
602 * Total number of objects in this site with reference counter greater
603 * than 0. Protected by lu_site::ls_guard.
608 * Top-level device for this stack.
610 struct lu_device *ls_top_dev;
612 * Wait-queue signaled when an object in this site is ultimately
613 * destroyed (lu_object_free()). It is used by lu_object_find() to
614 * wait before re-trying when object in the process of destruction is
615 * found in the hash table.
617 * If having a single wait-queue turns out to be a problem, a
618 * wait-queue per hash-table bucket can be easily implemented.
620 * \see htable_lookup().
622 cfs_waitq_t ls_marche_funebre;
624 /** statistical counters. Protected by nothing, races are accepted. */
630 * Number of hash-table entry checks made.
632 * ->s_cache_check / (->s_cache_miss + ->s_cache_hit)
634 * is an average number of hash slots inspected during single
638 /** Races with cache insertions. */
641 * Races with object destruction.
643 * \see lu_site::ls_marche_funebre.
645 __u32 s_cache_death_race;
650 * Linkage into global list of sites.
652 struct list_head ls_linkage;
653 struct lprocfs_stats *ls_time_stats;
657 * Constructors/destructors.
661 int lu_site_init (struct lu_site *s, struct lu_device *d);
662 void lu_site_fini (struct lu_site *s);
663 int lu_site_init_finish (struct lu_site *s);
664 void lu_stack_fini (const struct lu_env *env, struct lu_device *top);
665 void lu_device_get (struct lu_device *d);
666 void lu_device_put (struct lu_device *d);
667 int lu_device_init (struct lu_device *d, struct lu_device_type *t);
668 void lu_device_fini (struct lu_device *d);
669 int lu_object_header_init(struct lu_object_header *h);
670 void lu_object_header_fini(struct lu_object_header *h);
671 int lu_object_init (struct lu_object *o,
672 struct lu_object_header *h, struct lu_device *d);
673 void lu_object_fini (struct lu_object *o);
674 void lu_object_add_top (struct lu_object_header *h, struct lu_object *o);
675 void lu_object_add (struct lu_object *before, struct lu_object *o);
678 * Helpers to initialize and finalize device types.
681 int lu_device_type_init(struct lu_device_type *ldt);
682 void lu_device_type_fini(struct lu_device_type *ldt);
683 void lu_types_stop(void);
688 * Caching and reference counting.
693 * Acquire additional reference to the given object. This function is used to
694 * attain additional reference. To acquire initial reference use
697 static inline void lu_object_get(struct lu_object *o)
699 LASSERT(atomic_read(&o->lo_header->loh_ref) > 0);
700 atomic_inc(&o->lo_header->loh_ref);
704 * Return true of object will not be cached after last reference to it is
707 static inline int lu_object_is_dying(const struct lu_object_header *h)
709 return test_bit(LU_OBJECT_HEARD_BANSHEE, &h->loh_flags);
712 void lu_object_put(const struct lu_env *env, struct lu_object *o);
714 int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr);
716 void lu_site_print(const struct lu_env *env, struct lu_site *s, void *cookie,
717 lu_printer_t printer);
718 struct lu_object *lu_object_find(const struct lu_env *env,
719 struct lu_device *dev, const struct lu_fid *f,
720 const struct lu_object_conf *conf);
721 struct lu_object *lu_object_find_at(const struct lu_env *env,
722 struct lu_device *dev,
723 const struct lu_fid *f,
724 const struct lu_object_conf *conf);
725 struct lu_object *lu_object_find_slice(const struct lu_env *env,
726 struct lu_device *dev,
727 const struct lu_fid *f,
728 const struct lu_object_conf *conf);
737 * First (topmost) sub-object of given compound object
739 static inline struct lu_object *lu_object_top(struct lu_object_header *h)
741 LASSERT(!list_empty(&h->loh_layers));
742 return container_of0(h->loh_layers.next, struct lu_object, lo_linkage);
746 * Next sub-object in the layering
748 static inline struct lu_object *lu_object_next(const struct lu_object *o)
750 return container_of0(o->lo_linkage.next, struct lu_object, lo_linkage);
754 * Pointer to the fid of this object.
756 static inline const struct lu_fid *lu_object_fid(const struct lu_object *o)
758 return &o->lo_header->loh_fid;
762 * return device operations vector for this object
764 static const inline struct lu_device_operations *
765 lu_object_ops(const struct lu_object *o)
767 return o->lo_dev->ld_ops;
771 * Given a compound object, find its slice, corresponding to the device type
774 struct lu_object *lu_object_locate(struct lu_object_header *h,
775 const struct lu_device_type *dtype);
777 struct lu_cdebug_print_info {
780 const char *lpi_file;
786 * Printer function emitting messages through libcfs_debug_msg().
788 int lu_cdebug_printer(const struct lu_env *env,
789 void *cookie, const char *format, ...);
791 #define DECLARE_LU_CDEBUG_PRINT_INFO(var, mask) \
792 struct lu_cdebug_print_info var = { \
793 .lpi_subsys = DEBUG_SUBSYSTEM, \
794 .lpi_mask = (mask), \
795 .lpi_file = __FILE__, \
796 .lpi_fn = __FUNCTION__, \
797 .lpi_line = __LINE__ \
801 * Print object description followed by a user-supplied message.
803 #define LU_OBJECT_DEBUG(mask, env, object, format, ...) \
805 static DECLARE_LU_CDEBUG_PRINT_INFO(__info, mask); \
807 if (cdebug_show(mask, DEBUG_SUBSYSTEM)) { \
808 lu_object_print(env, &__info, lu_cdebug_printer, object); \
809 CDEBUG(mask, format , ## __VA_ARGS__); \
814 * Print short object description followed by a user-supplied message.
816 #define LU_OBJECT_HEADER(mask, env, object, format, ...) \
818 static DECLARE_LU_CDEBUG_PRINT_INFO(__info, mask); \
820 if (cdebug_show(mask, DEBUG_SUBSYSTEM)) { \
821 lu_object_header_print(env, &__info, lu_cdebug_printer, \
822 (object)->lo_header); \
823 lu_cdebug_printer(env, &__info, "\n"); \
824 CDEBUG(mask, format , ## __VA_ARGS__); \
828 void lu_object_print (const struct lu_env *env, void *cookie,
829 lu_printer_t printer, const struct lu_object *o);
830 void lu_object_header_print(const struct lu_env *env, void *cookie,
831 lu_printer_t printer,
832 const struct lu_object_header *hdr);
835 * Check object consistency.
837 int lu_object_invariant(const struct lu_object *o);
839 void lu_stack_fini(const struct lu_env *env, struct lu_device *top);
842 * Returns 1 iff object @o exists on the stable storage,
843 * returns -1 iff object @o is on remote server.
845 static inline int lu_object_exists(const struct lu_object *o)
849 attr = o->lo_header->loh_attr;
850 if (attr & LOHA_REMOTE)
852 else if (attr & LOHA_EXISTS)
858 static inline int lu_object_assert_exists(const struct lu_object *o)
860 return lu_object_exists(o) != 0;
863 static inline int lu_object_assert_not_exists(const struct lu_object *o)
865 return lu_object_exists(o) <= 0;
869 * Attr of this object.
871 static inline __u32 lu_object_attr(const struct lu_object *o)
873 LASSERT(lu_object_exists(o) > 0);
874 return o->lo_header->loh_attr;
877 static inline struct lu_ref_link *lu_object_ref_add(struct lu_object *o,
881 return lu_ref_add(&o->lo_header->loh_reference, scope, source);
884 static inline void lu_object_ref_del(struct lu_object *o,
885 const char *scope, const void *source)
887 lu_ref_del(&o->lo_header->loh_reference, scope, source);
890 static inline void lu_object_ref_del_at(struct lu_object *o,
891 struct lu_ref_link *link,
892 const char *scope, const void *source)
894 lu_ref_del_at(&o->lo_header->loh_reference, link, scope, source);
898 /* input params, should be filled out by mdt */
899 __u64 rp_hash; /* hash */
900 int rp_count; /* count in bytes */
901 int rp_npages; /* number of pages */
902 struct page **rp_pages; /* pointers to pages */
905 enum lu_xattr_flags {
906 LU_XATTR_REPLACE = (1 << 0),
907 LU_XATTR_CREATE = (1 << 1)
915 /** For lu_context health-checks */
916 enum lu_context_state {
924 * lu_context. Execution context for lu_object methods. Currently associated
927 * All lu_object methods, except device and device type methods (called during
928 * system initialization and shutdown) are executed "within" some
929 * lu_context. This means, that pointer to some "current" lu_context is passed
930 * as an argument to all methods.
932 * All service ptlrpc threads create lu_context as part of their
933 * initialization. It is possible to create "stand-alone" context for other
934 * execution environments (like system calls).
936 * lu_object methods mainly use lu_context through lu_context_key interface
937 * that allows each layer to associate arbitrary pieces of data with each
938 * context (see pthread_key_create(3) for similar interface).
940 * On a client, lu_context is bound to a thread, see cl_env_get().
942 * \see lu_context_key
946 * lu_context is used on the client side too. Yet we don't want to
947 * allocate values of server-side keys for the client contexts and
950 * To achieve this, set of tags in introduced. Contexts and keys are
951 * marked with tags. Key value are created only for context whose set
952 * of tags has non-empty intersection with one for key. Tags are taken
953 * from enum lu_context_tag.
957 * Pointer to the home service thread. NULL for other execution
960 struct ptlrpc_thread *lc_thread;
962 * Pointer to an array with key values. Internal implementation
966 enum lu_context_state lc_state;
968 * Linkage into a list of all remembered contexts. Only
969 * `non-transient' contexts, i.e., ones created for service threads
972 struct list_head lc_remember;
974 * Version counter used to skip calls to lu_context_refill() when no
975 * keys were registered.
981 * lu_context_key interface. Similar to pthread_key.
984 enum lu_context_tag {
986 * Thread on md server
988 LCT_MD_THREAD = 1 << 0,
990 * Thread on dt server
992 LCT_DT_THREAD = 1 << 1,
994 * Context for transaction handle
996 LCT_TX_HANDLE = 1 << 2,
1000 LCT_CL_THREAD = 1 << 3,
1002 * A per-request session on a server, and a per-system-call session on
1005 LCT_SESSION = 1 << 4,
1008 * Set when at least one of keys, having values in this context has
1009 * non-NULL lu_context_key::lct_exit() method. This is used to
1010 * optimize lu_context_exit() call.
1012 LCT_HAS_EXIT = 1 << 28,
1014 * Don't add references for modules creating key values in that context.
1015 * This is only for contexts used internally by lu_object framework.
1017 LCT_NOREF = 1 << 29,
1019 * Key is being prepared for retiring, don't create new values for it.
1021 LCT_QUIESCENT = 1 << 30,
1023 * Context should be remembered.
1025 LCT_REMEMBER = 1 << 31,
1027 * Contexts usable in cache shrinker thread.
1029 LCT_SHRINKER = LCT_MD_THREAD|LCT_DT_THREAD|LCT_CL_THREAD|LCT_NOREF
1033 * Key. Represents per-context value slot.
1035 * Keys are usually registered when module owning the key is initialized, and
1036 * de-registered when module is unloaded. Once key is registered, all new
1037 * contexts with matching tags, will get key value. "Old" contexts, already
1038 * initialized at the time of key registration, can be forced to get key value
1039 * by calling lu_context_refill().
1041 * Every key value is counted in lu_context_key::lct_used and acquires a
1042 * reference on an owning module. This means, that all key values have to be
1043 * destroyed before module can be unloaded. This is usually achieved by
1044 * stopping threads started by the module, that created contexts in their
1045 * entry functions. Situation is complicated by the threads shared by multiple
1046 * modules, like ptlrpcd daemon on a client. To work around this problem,
1047 * contexts, created in such threads, are `remembered' (see
1048 * LCT_REMEMBER)---i.e., added into a global list. When module is preparing
1049 * for unloading it does the following:
1051 * - marks its keys as `quiescent' (lu_context_tag::LCT_QUIESCENT)
1052 * preventing new key values from being allocated in the new contexts,
1055 * - scans a list of remembered contexts, destroying values of module
1056 * keys, thus releasing references to the module.
1058 * This is done by lu_context_key_quiesce(). If module is re-activated
1059 * before key has been de-registered, lu_context_key_revive() call clears
1060 * `quiescent' marker.
1062 * lu_context code doesn't provide any internal synchronization for these
1063 * activities---it's assumed that startup (including threads start-up) and
1064 * shutdown are serialized by some external means.
1068 struct lu_context_key {
1070 * Set of tags for which values of this key are to be instantiated.
1074 * Value constructor. This is called when new value is created for a
1075 * context. Returns pointer to new value of error pointer.
1077 void *(*lct_init)(const struct lu_context *ctx,
1078 struct lu_context_key *key);
1080 * Value destructor. Called when context with previously allocated
1081 * value of this slot is destroyed. \a data is a value that was returned
1082 * by a matching call to lu_context_key::lct_init().
1084 void (*lct_fini)(const struct lu_context *ctx,
1085 struct lu_context_key *key, void *data);
1087 * Optional method called on lu_context_exit() for all allocated
1088 * keys. Can be used by debugging code checking that locks are
1091 void (*lct_exit)(const struct lu_context *ctx,
1092 struct lu_context_key *key, void *data);
1094 * Internal implementation detail: index within lu_context::lc_value[]
1095 * reserved for this key.
1099 * Internal implementation detail: number of values created for this
1104 * Internal implementation detail: module for this key.
1106 struct module *lct_owner;
1108 * References to this key. For debugging.
1110 struct lu_ref lct_reference;
1113 #define LU_KEY_INIT(mod, type) \
1114 static void* mod##_key_init(const struct lu_context *ctx, \
1115 struct lu_context_key *key) \
1119 CLASSERT(CFS_PAGE_SIZE >= sizeof (*value)); \
1121 OBD_ALLOC_PTR(value); \
1122 if (value == NULL) \
1123 value = ERR_PTR(-ENOMEM); \
1127 struct __##mod##__dummy_init {;} /* semicolon catcher */
1129 #define LU_KEY_FINI(mod, type) \
1130 static void mod##_key_fini(const struct lu_context *ctx, \
1131 struct lu_context_key *key, void* data) \
1133 type *info = data; \
1135 OBD_FREE_PTR(info); \
1137 struct __##mod##__dummy_fini {;} /* semicolon catcher */
1139 #define LU_KEY_INIT_FINI(mod, type) \
1140 LU_KEY_INIT(mod,type); \
1141 LU_KEY_FINI(mod,type)
1143 #define LU_CONTEXT_KEY_DEFINE(mod, tags) \
1144 struct lu_context_key mod##_thread_key = { \
1146 .lct_init = mod##_key_init, \
1147 .lct_fini = mod##_key_fini \
1150 #define LU_CONTEXT_KEY_INIT(key) \
1152 (key)->lct_owner = THIS_MODULE; \
1155 int lu_context_key_register(struct lu_context_key *key);
1156 void lu_context_key_degister(struct lu_context_key *key);
1157 void *lu_context_key_get (const struct lu_context *ctx,
1158 const struct lu_context_key *key);
1159 void lu_context_key_quiesce (struct lu_context_key *key);
1160 void lu_context_key_revive (struct lu_context_key *key);
1164 * LU_KEY_INIT_GENERIC() has to be a macro to correctly determine an
1168 #define LU_KEY_INIT_GENERIC(mod) \
1169 static void mod##_key_init_generic(struct lu_context_key *k, ...) \
1171 struct lu_context_key *key = k; \
1174 va_start(args, k); \
1176 LU_CONTEXT_KEY_INIT(key); \
1177 key = va_arg(args, struct lu_context_key *); \
1178 } while (key != NULL); \
1182 #define LU_TYPE_INIT(mod, ...) \
1183 LU_KEY_INIT_GENERIC(mod) \
1184 static int mod##_type_init(struct lu_device_type *t) \
1186 mod##_key_init_generic(__VA_ARGS__, NULL); \
1187 return lu_context_key_register_many(__VA_ARGS__, NULL); \
1189 struct __##mod##_dummy_type_init {;}
1191 #define LU_TYPE_FINI(mod, ...) \
1192 static void mod##_type_fini(struct lu_device_type *t) \
1194 lu_context_key_degister_many(__VA_ARGS__, NULL); \
1196 struct __##mod##_dummy_type_fini {;}
1198 #define LU_TYPE_START(mod, ...) \
1199 static void mod##_type_start(struct lu_device_type *t) \
1202 struct __##mod##_dummy_type_start {;}
1204 #define LU_TYPE_STOP(mod, ...) \
1205 static void mod##_type_stop(struct lu_device_type *t) \
1208 struct __##mod##_dummy_type_stop {;}
1212 #define LU_TYPE_INIT_FINI(mod, ...) \
1213 LU_TYPE_INIT(mod, __VA_ARGS__); \
1214 LU_TYPE_FINI(mod, __VA_ARGS__); \
1215 LU_TYPE_START(mod, __VA_ARGS__); \
1216 LU_TYPE_STOP(mod, __VA_ARGS__)
1218 int lu_context_init (struct lu_context *ctx, __u32 tags);
1219 void lu_context_fini (struct lu_context *ctx);
1220 void lu_context_enter (struct lu_context *ctx);
1221 void lu_context_exit (struct lu_context *ctx);
1222 int lu_context_refill(struct lu_context *ctx);
1225 * Helper functions to operate on multiple keys. These are used by the default
1226 * device type operations, defined by LU_TYPE_INIT_FINI().
1229 int lu_context_key_register_many(struct lu_context_key *k, ...);
1230 void lu_context_key_degister_many(struct lu_context_key *k, ...);
1231 void lu_context_key_revive_many (struct lu_context_key *k, ...);
1232 void lu_context_key_quiesce_many (struct lu_context_key *k, ...);
1239 * "Local" context, used to store data instead of stack.
1241 struct lu_context le_ctx;
1243 * "Session" context for per-request data.
1245 struct lu_context *le_ses;
1248 int lu_env_init(struct lu_env *env, struct lu_context *ses, __u32 tags);
1249 void lu_env_fini(struct lu_env *env);
1251 /** @} lu_context */
1254 * Output site statistical counters into a buffer. Suitable for
1255 * ll_rd_*()-style functions.
1257 int lu_site_stats_print(const struct lu_site *s, char *page, int count);
1260 * Common name structure to be passed around for various name related methods.
1268 * Common buffer structure to be passed around for various xattr_{s,g}et()
1277 extern struct lu_buf LU_BUF_NULL;
1279 #define DLUBUF "(%p %z)"
1280 #define PLUBUF(buf) (buf)->lb_buf, (buf)->lb_len
1282 * One-time initializers, called at obdclass module initialization, not
1287 * Initialization of global lu_* data.
1289 int lu_global_init(void);
1292 * Dual to lu_global_init().
1294 void lu_global_fini(void);
1297 LU_TIME_FIND_LOOKUP,
1299 LU_TIME_FIND_INSERT,
1303 extern const char *lu_time_names[LU_TIME_NR];
1305 struct lu_kmem_descr {
1306 cfs_mem_cache_t **ckd_cache;
1307 const char *ckd_name;
1308 const size_t ckd_size;
1311 int lu_kmem_init(struct lu_kmem_descr *caches);
1312 void lu_kmem_fini(struct lu_kmem_descr *caches);
1316 #endif /* __LUSTRE_LU_OBJECT_H */