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Diffstat (limited to 'drivers/staging/lustre/lustre/include/lu_object.h')
-rw-r--r-- | drivers/staging/lustre/lustre/include/lu_object.h | 1335 |
1 files changed, 0 insertions, 1335 deletions
diff --git a/drivers/staging/lustre/lustre/include/lu_object.h b/drivers/staging/lustre/lustre/include/lu_object.h deleted file mode 100644 index 35c7b582f36d..000000000000 --- a/drivers/staging/lustre/lustre/include/lu_object.h +++ /dev/null @@ -1,1335 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * GPL HEADER START - * - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 only, - * as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License version 2 for more details (a copy is included - * in the LICENSE file that accompanied this code). - * - * You should have received a copy of the GNU General Public License - * version 2 along with this program; If not, see - * http://www.gnu.org/licenses/gpl-2.0.html - * - * GPL HEADER END - */ -/* - * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. - * Use is subject to license terms. - * - * Copyright (c) 2011, 2015, Intel Corporation. - */ -/* - * This file is part of Lustre, http://www.lustre.org/ - * Lustre is a trademark of Sun Microsystems, Inc. - */ - -#ifndef __LUSTRE_LU_OBJECT_H -#define __LUSTRE_LU_OBJECT_H - -#include <stdarg.h> -#include <linux/percpu_counter.h> -#include <linux/libcfs/libcfs.h> -#include <uapi/linux/lustre/lustre_idl.h> -#include <lu_ref.h> - -struct seq_file; -struct lustre_cfg; -struct lprocfs_stats; - -/** \defgroup lu lu - * lu_* data-types represent server-side entities shared by data and meta-data - * stacks. - * - * Design goals: - * - * -# support for layering. - * - * Server side object is split into layers, one per device in the - * corresponding device stack. Individual layer is represented by struct - * lu_object. Compound layered object --- by struct lu_object_header. Most - * interface functions take lu_object as an argument and operate on the - * whole compound object. This decision was made due to the following - * reasons: - * - * - it's envisaged that lu_object will be used much more often than - * lu_object_header; - * - * - we want lower (non-top) layers to be able to initiate operations - * on the whole object. - * - * Generic code supports layering more complex than simple stacking, e.g., - * it is possible that at some layer object "spawns" multiple sub-objects - * on the lower layer. - * - * -# fid-based identification. - * - * Compound object is uniquely identified by its fid. Objects are indexed - * by their fids (hash table is used for index). - * - * -# caching and life-cycle management. - * - * Object's life-time is controlled by reference counting. When reference - * count drops to 0, object is returned to cache. Cached objects still - * retain their identity (i.e., fid), and can be recovered from cache. - * - * Objects are kept in the global LRU list, and lu_site_purge() function - * can be used to reclaim given number of unused objects from the tail of - * the LRU. - * - * -# avoiding recursion. - * - * Generic code tries to replace recursion through layers by iterations - * where possible. Additionally to the end of reducing stack consumption, - * data, when practically possible, are allocated through lu_context_key - * interface rather than on stack. - * @{ - */ - -struct lu_site; -struct lu_object; -struct lu_device; -struct lu_object_header; -struct lu_context; -struct lu_env; - -/** - * Operations common for data and meta-data devices. - */ -struct lu_device_operations { - /** - * Allocate object for the given device (without lower-layer - * parts). This is called by lu_object_operations::loo_object_init() - * from the parent layer, and should setup at least lu_object::lo_dev - * and lu_object::lo_ops fields of resulting lu_object. - * - * Object creation protocol. - * - * Due to design goal of avoiding recursion, object creation (see - * lu_object_alloc()) is somewhat involved: - * - * - first, lu_device_operations::ldo_object_alloc() method of the - * top-level device in the stack is called. It should allocate top - * level object (including lu_object_header), but without any - * lower-layer sub-object(s). - * - * - then lu_object_alloc() sets fid in the header of newly created - * object. - * - * - then lu_object_operations::loo_object_init() is called. It has - * to allocate lower-layer object(s). To do this, - * lu_object_operations::loo_object_init() calls ldo_object_alloc() - * of the lower-layer device(s). - * - * - for all new objects allocated by - * lu_object_operations::loo_object_init() (and inserted into object - * stack), lu_object_operations::loo_object_init() is called again - * repeatedly, until no new objects are created. - * - * \post ergo(!IS_ERR(result), result->lo_dev == d && - * result->lo_ops != NULL); - */ - struct lu_object *(*ldo_object_alloc)(const struct lu_env *env, - const struct lu_object_header *h, - struct lu_device *d); - /** - * process config specific for device. - */ - int (*ldo_process_config)(const struct lu_env *env, - struct lu_device *, struct lustre_cfg *); - int (*ldo_recovery_complete)(const struct lu_env *, - struct lu_device *); - - /** - * initialize local objects for device. this method called after layer - * has been initialized (after LCFG_SETUP stage) and before it starts - * serving user requests. - */ - - int (*ldo_prepare)(const struct lu_env *, - struct lu_device *parent, - struct lu_device *dev); - -}; - -/** - * For lu_object_conf flags - */ -enum loc_flags { - /* This is a new object to be allocated, or the file - * corresponding to the object does not exists. - */ - LOC_F_NEW = 0x00000001, -}; - -/** - * Object configuration, describing particulars of object being created. On - * server this is not used, as server objects are full identified by fid. On - * client configuration contains struct lustre_md. - */ -struct lu_object_conf { - /** - * Some hints for obj find and alloc. - */ - enum loc_flags loc_flags; -}; - -/** - * Type of "printer" function used by lu_object_operations::loo_object_print() - * method. - * - * Printer function is needed to provide some flexibility in (semi-)debugging - * output: possible implementations: printk, CDEBUG, sysfs/seq_file - */ -typedef int (*lu_printer_t)(const struct lu_env *env, - void *cookie, const char *format, ...) - __printf(3, 4); - -/** - * Operations specific for particular lu_object. - */ -struct lu_object_operations { - /** - * Allocate lower-layer parts of the object by calling - * lu_device_operations::ldo_object_alloc() of the corresponding - * underlying device. - * - * This method is called once for each object inserted into object - * stack. It's responsibility of this method to insert lower-layer - * object(s) it create into appropriate places of object stack. - */ - int (*loo_object_init)(const struct lu_env *env, - struct lu_object *o, - const struct lu_object_conf *conf); - /** - * Called (in top-to-bottom order) during object allocation after all - * layers were allocated and initialized. Can be used to perform - * initialization depending on lower layers. - */ - int (*loo_object_start)(const struct lu_env *env, - struct lu_object *o); - /** - * Called before lu_object_operations::loo_object_free() to signal - * that object is being destroyed. Dual to - * lu_object_operations::loo_object_init(). - */ - void (*loo_object_delete)(const struct lu_env *env, - struct lu_object *o); - /** - * Dual to lu_device_operations::ldo_object_alloc(). Called when - * object is removed from memory. - */ - void (*loo_object_free)(const struct lu_env *env, - struct lu_object *o); - /** - * Called when last active reference to the object is released (and - * object returns to the cache). This method is optional. - */ - void (*loo_object_release)(const struct lu_env *env, - struct lu_object *o); - /** - * Optional debugging helper. Print given object. - */ - int (*loo_object_print)(const struct lu_env *env, void *cookie, - lu_printer_t p, const struct lu_object *o); - /** - * Optional debugging method. Returns true iff method is internally - * consistent. - */ - int (*loo_object_invariant)(const struct lu_object *o); -}; - -/** - * Type of lu_device. - */ -struct lu_device_type; - -/** - * Device: a layer in the server side abstraction stacking. - */ -struct lu_device { - /** - * reference count. This is incremented, in particular, on each object - * created at this layer. - * - * \todo XXX which means that atomic_t is probably too small. - */ - atomic_t ld_ref; - /** - * Pointer to device type. Never modified once set. - */ - struct lu_device_type *ld_type; - /** - * Operation vector for this device. - */ - const struct lu_device_operations *ld_ops; - /** - * Stack this device belongs to. - */ - struct lu_site *ld_site; - - /** \todo XXX: temporary back pointer into obd. */ - struct obd_device *ld_obd; - /** - * A list of references to this object, for debugging. - */ - struct lu_ref ld_reference; - /** - * Link the device to the site. - **/ - struct list_head ld_linkage; -}; - -struct lu_device_type_operations; - -/** - * Tag bits for device type. They are used to distinguish certain groups of - * device types. - */ -enum lu_device_tag { - /** this is meta-data device */ - LU_DEVICE_MD = (1 << 0), - /** this is data device */ - LU_DEVICE_DT = (1 << 1), - /** data device in the client stack */ - LU_DEVICE_CL = (1 << 2) -}; - -/** - * Type of device. - */ -struct lu_device_type { - /** - * Tag bits. Taken from enum lu_device_tag. Never modified once set. - */ - __u32 ldt_tags; - /** - * Name of this class. Unique system-wide. Never modified once set. - */ - char *ldt_name; - /** - * Operations for this type. - */ - const struct lu_device_type_operations *ldt_ops; - /** - * \todo XXX: temporary pointer to associated obd_type. - */ - struct obd_type *ldt_obd_type; - /** - * \todo XXX: temporary: context tags used by obd_*() calls. - */ - __u32 ldt_ctx_tags; - /** - * Number of existing device type instances. - */ - atomic_t ldt_device_nr; - /** - * Linkage into a global list of all device types. - * - * \see lu_device_types. - */ - struct list_head ldt_linkage; -}; - -/** - * Operations on a device type. - */ -struct lu_device_type_operations { - /** - * Allocate new device. - */ - struct lu_device *(*ldto_device_alloc)(const struct lu_env *env, - struct lu_device_type *t, - struct lustre_cfg *lcfg); - /** - * Free device. Dual to - * lu_device_type_operations::ldto_device_alloc(). Returns pointer to - * the next device in the stack. - */ - struct lu_device *(*ldto_device_free)(const struct lu_env *, - struct lu_device *); - - /** - * Initialize the devices after allocation - */ - int (*ldto_device_init)(const struct lu_env *env, - struct lu_device *, const char *, - struct lu_device *); - /** - * Finalize device. Dual to - * lu_device_type_operations::ldto_device_init(). Returns pointer to - * the next device in the stack. - */ - struct lu_device *(*ldto_device_fini)(const struct lu_env *env, - struct lu_device *); - /** - * Initialize device type. This is called on module load. - */ - int (*ldto_init)(struct lu_device_type *t); - /** - * Finalize device type. Dual to - * lu_device_type_operations::ldto_init(). Called on module unload. - */ - void (*ldto_fini)(struct lu_device_type *t); - /** - * Called when the first device is created. - */ - void (*ldto_start)(struct lu_device_type *t); - /** - * Called when number of devices drops to 0. - */ - void (*ldto_stop)(struct lu_device_type *t); -}; - -static inline int lu_device_is_md(const struct lu_device *d) -{ - return ergo(d, d->ld_type->ldt_tags & LU_DEVICE_MD); -} - -/** - * Common object attributes. - */ -struct lu_attr { - /** size in bytes */ - __u64 la_size; - /** modification time in seconds since Epoch */ - s64 la_mtime; - /** access time in seconds since Epoch */ - s64 la_atime; - /** change time in seconds since Epoch */ - s64 la_ctime; - /** 512-byte blocks allocated to object */ - __u64 la_blocks; - /** permission bits and file type */ - __u32 la_mode; - /** owner id */ - __u32 la_uid; - /** group id */ - __u32 la_gid; - /** object flags */ - __u32 la_flags; - /** number of persistent references to this object */ - __u32 la_nlink; - /** blk bits of the object*/ - __u32 la_blkbits; - /** blk size of the object*/ - __u32 la_blksize; - /** real device */ - __u32 la_rdev; - /** - * valid bits - * - * \see enum la_valid - */ - __u64 la_valid; -}; - -/** Bit-mask of valid attributes */ -enum la_valid { - LA_ATIME = 1 << 0, - LA_MTIME = 1 << 1, - LA_CTIME = 1 << 2, - LA_SIZE = 1 << 3, - LA_MODE = 1 << 4, - LA_UID = 1 << 5, - LA_GID = 1 << 6, - LA_BLOCKS = 1 << 7, - LA_TYPE = 1 << 8, - LA_FLAGS = 1 << 9, - LA_NLINK = 1 << 10, - LA_RDEV = 1 << 11, - LA_BLKSIZE = 1 << 12, - LA_KILL_SUID = 1 << 13, - LA_KILL_SGID = 1 << 14, -}; - -/** - * Layer in the layered object. - */ -struct lu_object { - /** - * Header for this object. - */ - struct lu_object_header *lo_header; - /** - * Device for this layer. - */ - struct lu_device *lo_dev; - /** - * Operations for this object. - */ - const struct lu_object_operations *lo_ops; - /** - * Linkage into list of all layers. - */ - struct list_head lo_linkage; - /** - * Link to the device, for debugging. - */ - struct lu_ref_link lo_dev_ref; -}; - -enum lu_object_header_flags { - /** - * Don't keep this object in cache. Object will be destroyed as soon - * as last reference to it is released. This flag cannot be cleared - * once set. - */ - LU_OBJECT_HEARD_BANSHEE = 0, - /** - * Mark this object has already been taken out of cache. - */ - LU_OBJECT_UNHASHED = 1, -}; - -enum lu_object_header_attr { - LOHA_EXISTS = 1 << 0, - LOHA_REMOTE = 1 << 1, - /** - * UNIX file type is stored in S_IFMT bits. - */ - LOHA_FT_START = 001 << 12, /**< S_IFIFO */ - LOHA_FT_END = 017 << 12, /**< S_IFMT */ -}; - -/** - * "Compound" object, consisting of multiple layers. - * - * Compound object with given fid is unique with given lu_site. - * - * Note, that object does *not* necessary correspond to the real object in the - * persistent storage: object is an anchor for locking and method calling, so - * it is created for things like not-yet-existing child created by mkdir or - * create calls. lu_object_operations::loo_exists() can be used to check - * whether object is backed by persistent storage entity. - */ -struct lu_object_header { - /** - * Fid, uniquely identifying this object. - */ - struct lu_fid loh_fid; - /** - * Object flags from enum lu_object_header_flags. Set and checked - * atomically. - */ - unsigned long loh_flags; - /** - * Object reference count. Protected by lu_site::ls_guard. - */ - atomic_t loh_ref; - /** - * Common object attributes, cached for efficiency. From enum - * lu_object_header_attr. - */ - __u32 loh_attr; - /** - * Linkage into per-site hash table. Protected by lu_site::ls_guard. - */ - struct hlist_node loh_hash; - /** - * Linkage into per-site LRU list. Protected by lu_site::ls_guard. - */ - struct list_head loh_lru; - /** - * Linkage into list of layers. Never modified once set (except lately - * during object destruction). No locking is necessary. - */ - struct list_head loh_layers; - /** - * A list of references to this object, for debugging. - */ - struct lu_ref loh_reference; -}; - -struct fld; - -struct lu_site_bkt_data { - /** - * number of object in this bucket on the lsb_lru list. - */ - long lsb_lru_len; - /** - * LRU list, updated on each access to object. Protected by - * bucket lock of lu_site::ls_obj_hash. - * - * "Cold" end of LRU is lu_site::ls_lru.next. Accessed object are - * moved to the lu_site::ls_lru.prev (this is due to the non-existence - * of list_for_each_entry_safe_reverse()). - */ - struct list_head lsb_lru; - /** - * Wait-queue signaled when an object in this site is ultimately - * destroyed (lu_object_free()). It is used by lu_object_find() to - * wait before re-trying when object in the process of destruction is - * found in the hash table. - * - * \see htable_lookup(). - */ - wait_queue_head_t lsb_marche_funebre; -}; - -enum { - LU_SS_CREATED = 0, - LU_SS_CACHE_HIT, - LU_SS_CACHE_MISS, - LU_SS_CACHE_RACE, - LU_SS_CACHE_DEATH_RACE, - LU_SS_LRU_PURGED, - LU_SS_LAST_STAT -}; - -/** - * lu_site is a "compartment" within which objects are unique, and LRU - * discipline is maintained. - * - * lu_site exists so that multiple layered stacks can co-exist in the same - * address space. - * - * lu_site has the same relation to lu_device as lu_object_header to - * lu_object. - */ -struct lu_site { - /** - * objects hash table - */ - struct cfs_hash *ls_obj_hash; - /** - * index of bucket on hash table while purging - */ - unsigned int ls_purge_start; - /** - * Top-level device for this stack. - */ - struct lu_device *ls_top_dev; - /** - * Bottom-level device for this stack - */ - struct lu_device *ls_bottom_dev; - /** - * Linkage into global list of sites. - */ - struct list_head ls_linkage; - /** - * List for lu device for this site, protected - * by ls_ld_lock. - **/ - struct list_head ls_ld_linkage; - spinlock_t ls_ld_lock; - - /** - * Lock to serialize site purge. - */ - struct mutex ls_purge_mutex; - - /** - * lu_site stats - */ - struct lprocfs_stats *ls_stats; - /** - * XXX: a hack! fld has to find md_site via site, remove when possible - */ - struct seq_server_site *ld_seq_site; - /** - * Number of objects in lsb_lru_lists - used for shrinking - */ - struct percpu_counter ls_lru_len_counter; -}; - -static inline struct lu_site_bkt_data * -lu_site_bkt_from_fid(struct lu_site *site, struct lu_fid *fid) -{ - struct cfs_hash_bd bd; - - cfs_hash_bd_get(site->ls_obj_hash, fid, &bd); - return cfs_hash_bd_extra_get(site->ls_obj_hash, &bd); -} - -static inline struct seq_server_site *lu_site2seq(const struct lu_site *s) -{ - return s->ld_seq_site; -} - -/** \name ctors - * Constructors/destructors. - * @{ - */ - -int lu_site_init(struct lu_site *s, struct lu_device *d); -void lu_site_fini(struct lu_site *s); -int lu_site_init_finish(struct lu_site *s); -void lu_stack_fini(const struct lu_env *env, struct lu_device *top); -void lu_device_get(struct lu_device *d); -void lu_device_put(struct lu_device *d); -int lu_device_init(struct lu_device *d, struct lu_device_type *t); -void lu_device_fini(struct lu_device *d); -int lu_object_header_init(struct lu_object_header *h); -void lu_object_header_fini(struct lu_object_header *h); -int lu_object_init(struct lu_object *o, - struct lu_object_header *h, struct lu_device *d); -void lu_object_fini(struct lu_object *o); -void lu_object_add_top(struct lu_object_header *h, struct lu_object *o); -void lu_object_add(struct lu_object *before, struct lu_object *o); - -/** - * Helpers to initialize and finalize device types. - */ - -int lu_device_type_init(struct lu_device_type *ldt); -void lu_device_type_fini(struct lu_device_type *ldt); - -/** @} ctors */ - -/** \name caching - * Caching and reference counting. - * @{ - */ - -/** - * Acquire additional reference to the given object. This function is used to - * attain additional reference. To acquire initial reference use - * lu_object_find(). - */ -static inline void lu_object_get(struct lu_object *o) -{ - LASSERT(atomic_read(&o->lo_header->loh_ref) > 0); - atomic_inc(&o->lo_header->loh_ref); -} - -/** - * Return true of object will not be cached after last reference to it is - * released. - */ -static inline int lu_object_is_dying(const struct lu_object_header *h) -{ - return test_bit(LU_OBJECT_HEARD_BANSHEE, &h->loh_flags); -} - -void lu_object_put(const struct lu_env *env, struct lu_object *o); -void lu_object_unhash(const struct lu_env *env, struct lu_object *o); -int lu_site_purge_objects(const struct lu_env *env, struct lu_site *s, int nr, - bool canblock); - -static inline int lu_site_purge(const struct lu_env *env, struct lu_site *s, - int nr) -{ - return lu_site_purge_objects(env, s, nr, true); -} - -void lu_site_print(const struct lu_env *env, struct lu_site *s, void *cookie, - lu_printer_t printer); -struct lu_object *lu_object_find_at(const struct lu_env *env, - struct lu_device *dev, - const struct lu_fid *f, - const struct lu_object_conf *conf); -struct lu_object *lu_object_find_slice(const struct lu_env *env, - struct lu_device *dev, - const struct lu_fid *f, - const struct lu_object_conf *conf); -/** @} caching */ - -/** \name helpers - * Helpers. - * @{ - */ - -/** - * First (topmost) sub-object of given compound object - */ -static inline struct lu_object *lu_object_top(struct lu_object_header *h) -{ - LASSERT(!list_empty(&h->loh_layers)); - return container_of0(h->loh_layers.next, struct lu_object, lo_linkage); -} - -/** - * Next sub-object in the layering - */ -static inline struct lu_object *lu_object_next(const struct lu_object *o) -{ - return container_of0(o->lo_linkage.next, struct lu_object, lo_linkage); -} - -/** - * Pointer to the fid of this object. - */ -static inline const struct lu_fid *lu_object_fid(const struct lu_object *o) -{ - return &o->lo_header->loh_fid; -} - -/** - * return device operations vector for this object - */ -static inline const struct lu_device_operations * -lu_object_ops(const struct lu_object *o) -{ - return o->lo_dev->ld_ops; -} - -/** - * Given a compound object, find its slice, corresponding to the device type - * \a dtype. - */ -struct lu_object *lu_object_locate(struct lu_object_header *h, - const struct lu_device_type *dtype); - -/** - * Printer function emitting messages through libcfs_debug_msg(). - */ -int lu_cdebug_printer(const struct lu_env *env, - void *cookie, const char *format, ...); - -/** - * Print object description followed by a user-supplied message. - */ -#define LU_OBJECT_DEBUG(mask, env, object, format, ...) \ -do { \ - if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) { \ - LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, NULL); \ - lu_object_print(env, &msgdata, lu_cdebug_printer, object);\ - CDEBUG(mask, format "\n", ## __VA_ARGS__); \ - } \ -} while (0) - -/** - * Print short object description followed by a user-supplied message. - */ -#define LU_OBJECT_HEADER(mask, env, object, format, ...) \ -do { \ - if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) { \ - LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, NULL); \ - lu_object_header_print(env, &msgdata, lu_cdebug_printer,\ - (object)->lo_header); \ - lu_cdebug_printer(env, &msgdata, "\n"); \ - CDEBUG(mask, format, ## __VA_ARGS__); \ - } \ -} while (0) - -void lu_object_print (const struct lu_env *env, void *cookie, - lu_printer_t printer, const struct lu_object *o); -void lu_object_header_print(const struct lu_env *env, void *cookie, - lu_printer_t printer, - const struct lu_object_header *hdr); - -/** - * Check object consistency. - */ -int lu_object_invariant(const struct lu_object *o); - -/** - * Check whether object exists, no matter on local or remote storage. - * Note: LOHA_EXISTS will be set once some one created the object, - * and it does not needs to be committed to storage. - */ -#define lu_object_exists(o) ((o)->lo_header->loh_attr & LOHA_EXISTS) - -/** - * Check whether object on the remote storage. - */ -#define lu_object_remote(o) unlikely((o)->lo_header->loh_attr & LOHA_REMOTE) - -static inline int lu_object_assert_exists(const struct lu_object *o) -{ - return lu_object_exists(o); -} - -static inline int lu_object_assert_not_exists(const struct lu_object *o) -{ - return !lu_object_exists(o); -} - -/** - * Attr of this object. - */ -static inline __u32 lu_object_attr(const struct lu_object *o) -{ - LASSERT(lu_object_exists(o) != 0); - return o->lo_header->loh_attr; -} - -static inline void lu_object_ref_add(struct lu_object *o, - const char *scope, - const void *source) -{ - lu_ref_add(&o->lo_header->loh_reference, scope, source); -} - -static inline void lu_object_ref_add_at(struct lu_object *o, - struct lu_ref_link *link, - const char *scope, - const void *source) -{ - lu_ref_add_at(&o->lo_header->loh_reference, link, scope, source); -} - -static inline void lu_object_ref_del(struct lu_object *o, - const char *scope, const void *source) -{ - lu_ref_del(&o->lo_header->loh_reference, scope, source); -} - -static inline void lu_object_ref_del_at(struct lu_object *o, - struct lu_ref_link *link, - const char *scope, const void *source) -{ - lu_ref_del_at(&o->lo_header->loh_reference, link, scope, source); -} - -/** input params, should be filled out by mdt */ -struct lu_rdpg { - /** hash */ - __u64 rp_hash; - /** count in bytes */ - unsigned int rp_count; - /** number of pages */ - unsigned int rp_npages; - /** requested attr */ - __u32 rp_attrs; - /** pointers to pages */ - struct page **rp_pages; -}; - -enum lu_xattr_flags { - LU_XATTR_REPLACE = (1 << 0), - LU_XATTR_CREATE = (1 << 1) -}; - -/** @} helpers */ - -/** \name lu_context - * @{ - */ - -/** For lu_context health-checks */ -enum lu_context_state { - LCS_INITIALIZED = 1, - LCS_ENTERED, - LCS_LEFT, - LCS_FINALIZED -}; - -/** - * lu_context. Execution context for lu_object methods. Currently associated - * with thread. - * - * All lu_object methods, except device and device type methods (called during - * system initialization and shutdown) are executed "within" some - * lu_context. This means, that pointer to some "current" lu_context is passed - * as an argument to all methods. - * - * All service ptlrpc threads create lu_context as part of their - * initialization. It is possible to create "stand-alone" context for other - * execution environments (like system calls). - * - * lu_object methods mainly use lu_context through lu_context_key interface - * that allows each layer to associate arbitrary pieces of data with each - * context (see pthread_key_create(3) for similar interface). - * - * On a client, lu_context is bound to a thread, see cl_env_get(). - * - * \see lu_context_key - */ -struct lu_context { - /** - * lu_context is used on the client side too. Yet we don't want to - * allocate values of server-side keys for the client contexts and - * vice versa. - * - * To achieve this, set of tags in introduced. Contexts and keys are - * marked with tags. Key value are created only for context whose set - * of tags has non-empty intersection with one for key. Tags are taken - * from enum lu_context_tag. - */ - __u32 lc_tags; - enum lu_context_state lc_state; - /** - * Pointer to the home service thread. NULL for other execution - * contexts. - */ - struct ptlrpc_thread *lc_thread; - /** - * Pointer to an array with key values. Internal implementation - * detail. - */ - void **lc_value; - /** - * Linkage into a list of all remembered contexts. Only - * `non-transient' contexts, i.e., ones created for service threads - * are placed here. - */ - struct list_head lc_remember; - /** - * Version counter used to skip calls to lu_context_refill() when no - * keys were registered. - */ - unsigned int lc_version; - /** - * Debugging cookie. - */ - unsigned int lc_cookie; -}; - -/** - * lu_context_key interface. Similar to pthread_key. - */ - -enum lu_context_tag { - /** - * Thread on md server - */ - LCT_MD_THREAD = 1 << 0, - /** - * Thread on dt server - */ - LCT_DT_THREAD = 1 << 1, - /** - * Context for transaction handle - */ - LCT_TX_HANDLE = 1 << 2, - /** - * Thread on client - */ - LCT_CL_THREAD = 1 << 3, - /** - * A per-request session on a server, and a per-system-call session on - * a client. - */ - LCT_SESSION = 1 << 4, - /** - * A per-request data on OSP device - */ - LCT_OSP_THREAD = 1 << 5, - /** - * MGS device thread - */ - LCT_MG_THREAD = 1 << 6, - /** - * Context for local operations - */ - LCT_LOCAL = 1 << 7, - /** - * session for server thread - **/ - LCT_SERVER_SESSION = BIT(8), - /** - * Set when at least one of keys, having values in this context has - * non-NULL lu_context_key::lct_exit() method. This is used to - * optimize lu_context_exit() call. - */ - LCT_HAS_EXIT = 1 << 28, - /** - * Don't add references for modules creating key values in that context. - * This is only for contexts used internally by lu_object framework. - */ - LCT_NOREF = 1 << 29, - /** - * Key is being prepared for retiring, don't create new values for it. - */ - LCT_QUIESCENT = 1 << 30, - /** - * Context should be remembered. - */ - LCT_REMEMBER = 1 << 31, - /** - * Contexts usable in cache shrinker thread. - */ - LCT_SHRINKER = LCT_MD_THREAD | LCT_DT_THREAD | LCT_CL_THREAD | - LCT_NOREF -}; - -/** - * Key. Represents per-context value slot. - * - * Keys are usually registered when module owning the key is initialized, and - * de-registered when module is unloaded. Once key is registered, all new - * contexts with matching tags, will get key value. "Old" contexts, already - * initialized at the time of key registration, can be forced to get key value - * by calling lu_context_refill(). - * - * Every key value is counted in lu_context_key::lct_used and acquires a - * reference on an owning module. This means, that all key values have to be - * destroyed before module can be unloaded. This is usually achieved by - * stopping threads started by the module, that created contexts in their - * entry functions. Situation is complicated by the threads shared by multiple - * modules, like ptlrpcd daemon on a client. To work around this problem, - * contexts, created in such threads, are `remembered' (see - * LCT_REMEMBER)---i.e., added into a global list. When module is preparing - * for unloading it does the following: - * - * - marks its keys as `quiescent' (lu_context_tag::LCT_QUIESCENT) - * preventing new key values from being allocated in the new contexts, - * and - * - * - scans a list of remembered contexts, destroying values of module - * keys, thus releasing references to the module. - * - * This is done by lu_context_key_quiesce(). If module is re-activated - * before key has been de-registered, lu_context_key_revive() call clears - * `quiescent' marker. - * - * lu_context code doesn't provide any internal synchronization for these - * activities---it's assumed that startup (including threads start-up) and - * shutdown are serialized by some external means. - * - * \see lu_context - */ -struct lu_context_key { - /** - * Set of tags for which values of this key are to be instantiated. - */ - __u32 lct_tags; - /** - * Value constructor. This is called when new value is created for a - * context. Returns pointer to new value of error pointer. - */ - void *(*lct_init)(const struct lu_context *ctx, - struct lu_context_key *key); - /** - * Value destructor. Called when context with previously allocated - * value of this slot is destroyed. \a data is a value that was returned - * by a matching call to lu_context_key::lct_init(). - */ - void (*lct_fini)(const struct lu_context *ctx, - struct lu_context_key *key, void *data); - /** - * Optional method called on lu_context_exit() for all allocated - * keys. Can be used by debugging code checking that locks are - * released, etc. - */ - void (*lct_exit)(const struct lu_context *ctx, - struct lu_context_key *key, void *data); - /** - * Internal implementation detail: index within lu_context::lc_value[] - * reserved for this key. - */ - int lct_index; - /** - * Internal implementation detail: number of values created for this - * key. - */ - atomic_t lct_used; - /** - * Internal implementation detail: module for this key. - */ - struct module *lct_owner; - /** - * References to this key. For debugging. - */ - struct lu_ref lct_reference; -}; - -#define LU_KEY_INIT(mod, type) \ - static void *mod##_key_init(const struct lu_context *ctx, \ - struct lu_context_key *key) \ - { \ - type *value; \ - \ - BUILD_BUG_ON(sizeof(*value) > PAGE_SIZE); \ - \ - value = kzalloc(sizeof(*value), GFP_NOFS); \ - if (!value) \ - value = ERR_PTR(-ENOMEM); \ - \ - return value; \ - } \ - struct __##mod##__dummy_init {; } /* semicolon catcher */ - -#define LU_KEY_FINI(mod, type) \ - static void mod##_key_fini(const struct lu_context *ctx, \ - struct lu_context_key *key, void *data) \ - { \ - type *info = data; \ - \ - kfree(info); \ - } \ - struct __##mod##__dummy_fini {; } /* semicolon catcher */ - -#define LU_KEY_INIT_FINI(mod, type) \ - LU_KEY_INIT(mod, type); \ - LU_KEY_FINI(mod, type) - -#define LU_CONTEXT_KEY_DEFINE(mod, tags) \ - struct lu_context_key mod##_thread_key = { \ - .lct_tags = tags, \ - .lct_init = mod##_key_init, \ - .lct_fini = mod##_key_fini \ - } - -#define LU_CONTEXT_KEY_INIT(key) \ -do { \ - (key)->lct_owner = THIS_MODULE; \ -} while (0) - -int lu_context_key_register(struct lu_context_key *key); -void lu_context_key_degister(struct lu_context_key *key); -void *lu_context_key_get(const struct lu_context *ctx, - const struct lu_context_key *key); -void lu_context_key_quiesce(struct lu_context_key *key); -void lu_context_key_revive(struct lu_context_key *key); - -/* - * LU_KEY_INIT_GENERIC() has to be a macro to correctly determine an - * owning module. - */ - -#define LU_KEY_INIT_GENERIC(mod) \ - static void mod##_key_init_generic(struct lu_context_key *k, ...) \ - { \ - struct lu_context_key *key = k; \ - va_list args; \ - \ - va_start(args, k); \ - do { \ - LU_CONTEXT_KEY_INIT(key); \ - key = va_arg(args, struct lu_context_key *); \ - } while (key); \ - va_end(args); \ - } - -#define LU_TYPE_INIT(mod, ...) \ - LU_KEY_INIT_GENERIC(mod) \ - static int mod##_type_init(struct lu_device_type *t) \ - { \ - mod##_key_init_generic(__VA_ARGS__, NULL); \ - return lu_context_key_register_many(__VA_ARGS__, NULL); \ - } \ - struct __##mod##_dummy_type_init {; } - -#define LU_TYPE_FINI(mod, ...) \ - static void mod##_type_fini(struct lu_device_type *t) \ - { \ - lu_context_key_degister_many(__VA_ARGS__, NULL); \ - } \ - struct __##mod##_dummy_type_fini {; } - -#define LU_TYPE_START(mod, ...) \ - static void mod##_type_start(struct lu_device_type *t) \ - { \ - lu_context_key_revive_many(__VA_ARGS__, NULL); \ - } \ - struct __##mod##_dummy_type_start {; } - -#define LU_TYPE_STOP(mod, ...) \ - static void mod##_type_stop(struct lu_device_type *t) \ - { \ - lu_context_key_quiesce_many(__VA_ARGS__, NULL); \ - } \ - struct __##mod##_dummy_type_stop {; } - -#define LU_TYPE_INIT_FINI(mod, ...) \ - LU_TYPE_INIT(mod, __VA_ARGS__); \ - LU_TYPE_FINI(mod, __VA_ARGS__); \ - LU_TYPE_START(mod, __VA_ARGS__); \ - LU_TYPE_STOP(mod, __VA_ARGS__) - -int lu_context_init(struct lu_context *ctx, __u32 tags); -void lu_context_fini(struct lu_context *ctx); -void lu_context_enter(struct lu_context *ctx); -void lu_context_exit(struct lu_context *ctx); -int lu_context_refill(struct lu_context *ctx); - -/* - * Helper functions to operate on multiple keys. These are used by the default - * device type operations, defined by LU_TYPE_INIT_FINI(). - */ - -int lu_context_key_register_many(struct lu_context_key *k, ...); -void lu_context_key_degister_many(struct lu_context_key *k, ...); -void lu_context_key_revive_many(struct lu_context_key *k, ...); -void lu_context_key_quiesce_many(struct lu_context_key *k, ...); - -/** - * Environment. - */ -struct lu_env { - /** - * "Local" context, used to store data instead of stack. - */ - struct lu_context le_ctx; - /** - * "Session" context for per-request data. - */ - struct lu_context *le_ses; -}; - -int lu_env_init(struct lu_env *env, __u32 tags); -void lu_env_fini(struct lu_env *env); -int lu_env_refill(struct lu_env *env); - -/** @} lu_context */ - -/** - * Output site statistical counters into a buffer. Suitable for - * ll_rd_*()-style functions. - */ -int lu_site_stats_print(const struct lu_site *s, struct seq_file *m); - -/** - * Common name structure to be passed around for various name related methods. - */ -struct lu_name { - const char *ln_name; - int ln_namelen; -}; - -/** - * Validate names (path components) - * - * To be valid \a name must be non-empty, '\0' terminated of length \a - * name_len, and not contain '/'. The maximum length of a name (before - * say -ENAMETOOLONG will be returned) is really controlled by llite - * and the server. We only check for something insane coming from bad - * integer handling here. - */ -static inline bool lu_name_is_valid_2(const char *name, size_t name_len) -{ - return name && name_len > 0 && name_len < INT_MAX && - name[name_len] == '\0' && strlen(name) == name_len && - !memchr(name, '/', name_len); -} - -/** - * Common buffer structure to be passed around for various xattr_{s,g}et() - * methods. - */ -struct lu_buf { - void *lb_buf; - size_t lb_len; -}; - -/** - * One-time initializers, called at obdclass module initialization, not - * exported. - */ - -/** - * Initialization of global lu_* data. - */ -int lu_global_init(void); - -/** - * Dual to lu_global_init(). - */ -void lu_global_fini(void); - -struct lu_kmem_descr { - struct kmem_cache **ckd_cache; - const char *ckd_name; - const size_t ckd_size; -}; - -int lu_kmem_init(struct lu_kmem_descr *caches); -void lu_kmem_fini(struct lu_kmem_descr *caches); - -extern __u32 lu_context_tags_default; -extern __u32 lu_session_tags_default; - -/** @} lu */ -#endif /* __LUSTRE_LU_OBJECT_H */ |