--- /dev/null
+/*
+ * 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.sun.com/software/products/lustre/docs/GPLv2.pdf
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, 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 "../../include/linux/libcfs/libcfs.h"
+#include "lustre/lustre_idl.h"
+#include "lu_ref.h"
+
+struct seq_file;
+struct proc_dir_entry;
+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
+ */
+typedef enum {
+ /* This is a new object to be allocated, or the file
+ * corresponding to the object does not exists. */
+ LOC_F_NEW = 0x00000001,
+} loc_flags_t;
+
+/**
+ * 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.
+ */
+ loc_flags_t 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;
+ struct proc_dir_entry *ld_proc_entry;
+
+ /** \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.
+ */
+ unsigned 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 != NULL, 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 busy object on this bucket
+ */
+ long lsb_busy;
+ /**
+ * 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
+ */
+ 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;
+
+ /**
+ * 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;
+};
+
+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);
+
+void lu_dev_add_linkage(struct lu_site *s, struct lu_device *d);
+void lu_dev_del_linkage(struct lu_site *s, struct lu_device *d);
+
+/**
+ * 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);
+void lu_types_stop(void);
+
+/** @} 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_put_nocache(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(const struct lu_env *env, struct lu_site *s, int nr);
+
+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(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_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 const inline 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 { \
+ LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, NULL); \
+ \
+ if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) { \
+ lu_object_print(env, &msgdata, lu_cdebug_printer, object);\
+ CDEBUG(mask, format , ## __VA_ARGS__); \
+ } \
+} while (0)
+
+/**
+ * Print short object description followed by a user-supplied message.
+ */
+#define LU_OBJECT_HEADER(mask, env, object, format, ...) \
+do { \
+ LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, NULL); \
+ \
+ if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) { \
+ 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 lc_version;
+ /**
+ * Debugging cookie.
+ */
+ unsigned 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,
+ /**
+ * 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; \
+ \
+ CLASSERT(PAGE_CACHE_SIZE >= sizeof (*value)); \
+ \
+ OBD_ALLOC_PTR(value); \
+ if (value == NULL) \
+ 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; \
+ \
+ OBD_FREE_PTR(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 != NULL); \
+ 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, ...);
+
+/*
+ * update/clear ctx/ses tags.
+ */
+void lu_context_tags_update(__u32 tags);
+void lu_context_tags_clear(__u32 tags);
+void lu_session_tags_update(__u32 tags);
+void lu_session_tags_clear(__u32 tags);
+
+/**
+ * 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);
+int lu_env_refill_by_tags(struct lu_env *env, __u32 ctags, __u32 stags);
+
+/** @} 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;
+};
+
+/**
+ * Common buffer structure to be passed around for various xattr_{s,g}et()
+ * methods.
+ */
+struct lu_buf {
+ void *lb_buf;
+ ssize_t lb_len;
+};
+
+#define DLUBUF "(%p %zu)"
+#define PLUBUF(buf) (buf)->lb_buf, (buf)->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);
+
+void lu_object_assign_fid(const struct lu_env *env, struct lu_object *o,
+ const struct lu_fid *fid);
+struct lu_object *lu_object_anon(const struct lu_env *env,
+ struct lu_device *dev,
+ const struct lu_object_conf *conf);
+
+/** null buffer */
+extern struct lu_buf LU_BUF_NULL;
+
+void lu_buf_free(struct lu_buf *buf);
+void lu_buf_alloc(struct lu_buf *buf, int size);
+void lu_buf_realloc(struct lu_buf *buf, int size);
+
+int lu_buf_check_and_grow(struct lu_buf *buf, int len);
+struct lu_buf *lu_buf_check_and_alloc(struct lu_buf *buf, int len);
+
+/** @} lu */
+#endif /* __LUSTRE_LU_OBJECT_H */
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