X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Finclude%2Fmd_object.h;h=f8d0f465eb891833484d87a44f21899a01ec4b3b;hp=68fadcf26bc779cfdb36fbe987a0d691adef3d24;hb=8701e7e4b5ec1b34700c95b9b6588f4745730b72;hpb=4fd92d576124fd7772c9f718b83eb67f500e5cec diff --git a/lustre/include/md_object.h b/lustre/include/md_object.h index 68fadcf..f8d0f46 100644 --- a/lustre/include/md_object.h +++ b/lustre/include/md_object.h @@ -1,6 +1,4 @@ -/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- - * vim:expandtab:shiftwidth=8:tabstop=8: - * +/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. @@ -29,7 +27,7 @@ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * - * Copyright (c) 2011, 2012, Whamcloud, Inc. + * Copyright (c) 2011, 2013, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -59,81 +57,32 @@ * super-class definitions. */ #include -#include - -/* LU-1051, temperary solution to reduce llog credits */ -#define DECLARE_LLOG_REWRITE 0 -#define DECLARE_LLOG_WRITE INT_MAX struct md_device; struct md_device_operations; struct md_object; struct obd_export; -enum { - UCRED_INVALID = -1, - UCRED_INIT = 0, - UCRED_OLD = 1, - UCRED_NEW = 2 -}; - -struct md_ucred { - __u32 mu_valid; - __u32 mu_o_uid; - __u32 mu_o_gid; - __u32 mu_o_fsuid; - __u32 mu_o_fsgid; - __u32 mu_uid; - __u32 mu_gid; - __u32 mu_fsuid; - __u32 mu_fsgid; - __u32 mu_suppgids[2]; - cfs_cap_t mu_cap; - __u32 mu_umask; - cfs_group_info_t *mu_ginfo; - struct md_identity *mu_identity; -}; - -enum { - MD_CAPAINFO_MAX = 5 -}; - -/** there are at most 5 fids in one operation, see rename, NOTE the last one - * is a temporary one used for is_subdir() */ -struct md_capainfo { - __u32 mc_auth; - __u32 mc_padding; - struct lu_fid mc_fid[MD_CAPAINFO_MAX]; - struct lustre_capa *mc_capa[MD_CAPAINFO_MAX]; -}; - struct md_quota { struct obd_export *mq_exp; }; -/** - * Implemented in mdd/mdd_handler.c. - * - * XXX should be moved into separate .h/.c together with all md security - * related definitions. - */ -struct md_ucred *md_ucred(const struct lu_env *env); -struct md_capainfo *md_capainfo(const struct lu_env *env); struct md_quota *md_quota(const struct lu_env *env); /** metadata attributes */ enum ma_valid { - MA_INODE = (1 << 0), - MA_LOV = (1 << 1), - MA_COOKIE = (1 << 2), - MA_FLAGS = (1 << 3), - MA_LMV = (1 << 4), - MA_ACL_DEF = (1 << 5), - MA_LOV_DEF = (1 << 6), - MA_LAY_GEN = (1 << 7), - MA_HSM = (1 << 8), - MA_SOM = (1 << 9), - MA_PFID = (1 << 10) + MA_INODE = (1 << 0), + MA_LOV = (1 << 1), + MA_COOKIE = (1 << 2), + MA_FLAGS = (1 << 3), + MA_LMV = (1 << 4), + MA_ACL_DEF = (1 << 5), + MA_LOV_DEF = (1 << 6), + MA_LAY_GEN = (1 << 7), + MA_HSM = (1 << 8), + MA_SOM = (1 << 9), + MA_PFID = (1 << 10), + MA_LMV_DEF = (1 << 11) }; typedef enum { @@ -154,18 +103,30 @@ typedef enum { MDT_PDO_LOCK = (1 << 1) } mdl_type_t; +/* memory structure for hsm attributes + * for fields description see the on disk structure hsm_attrs + * which is defined in lustre_idl.h + */ struct md_hsm { - __u32 mh_flags; - __u32 mh_archive_number; + __u32 mh_compat; + __u32 mh_flags; + __u64 mh_arch_id; + __u64 mh_arch_ver; }; #define IOEPOCH_INVAL 0 +/* memory structure for som attributes + * for fields description see the on disk structure som_attrs + * which is defined in lustre_idl.h + */ struct md_som_data { - __u64 msd_ioepoch; - __u64 msd_size; - __u64 msd_blocks; - __u64 msd_mountid; + __u32 msd_compat; + __u32 msd_incompat; + __u64 msd_ioepoch; + __u64 msd_size; + __u64 msd_blocks; + __u64 msd_mountid; }; struct md_attr { @@ -176,16 +137,13 @@ struct md_attr { struct lu_fid ma_pfid; struct md_hsm ma_hsm; struct lov_mds_md *ma_lmm; - struct lmv_stripe_md *ma_lmv; + union lmv_mds_md *ma_lmv; void *ma_acl; - struct llog_cookie *ma_cookie; struct lustre_capa *ma_capa; struct md_som_data *ma_som; int ma_lmm_size; - int ma_big_lmm_used:1; int ma_lmv_size; int ma_acl_size; - int ma_cookie_size; __u16 ma_layout_gen; }; @@ -204,25 +162,23 @@ struct md_op_spec { int eadatalen; } sp_ea; } u; - /** don't create lov objects or llog cookie - this replay */ - int no_create; /** Create flag from client: such as MDS_OPEN_CREAT, and others. */ __u64 sp_cr_flags; - /** Should mdd do lookup sanity check or not. */ - int sp_cr_lookup; + /** don't create lov objects or llog cookie - this replay */ + unsigned int no_create:1, + sp_cr_lookup:1, /* do lookup sanity check or not. */ + sp_rm_entry:1; /* only remove name entry */ - /** Current lock mode for parent dir where create is performing. */ + /** Current lock mode for parent dir where create is performing. */ mdl_mode_t sp_cr_mode; - /** Check for split */ - int sp_ck_split; - /** to create directory */ const struct dt_index_features *sp_feat; }; +union ldlm_policy_data; /** * Operations implemented for each md object (both directory and leaf). */ @@ -250,6 +206,11 @@ struct md_object_operations { int (*moo_xattr_del)(const struct lu_env *env, struct md_object *obj, const char *name); + /** This method is used to swap the layouts between 2 objects */ + int (*moo_swap_layouts)(const struct lu_env *env, + struct md_object *obj1, struct md_object *obj2, + __u64 flags); + /** \retval number of bytes actually read upon success */ int (*moo_readpage)(const struct lu_env *env, struct md_object *obj, const struct lu_rdpg *rdpg); @@ -283,14 +244,21 @@ struct md_object_operations { struct lustre_capa *, int renewal); int (*moo_object_sync)(const struct lu_env *, struct md_object *); - int (*moo_path)(const struct lu_env *env, struct md_object *obj, - char *path, int pathlen, __u64 *recno, int *linkno); - int (*moo_file_lock)(const struct lu_env *env, struct md_object *obj, - struct lov_mds_md *lmm, struct ldlm_extent *extent, - struct lustre_handle *lockh); - int (*moo_file_unlock)(const struct lu_env *env, struct md_object *obj, - struct lov_mds_md *lmm, - struct lustre_handle *lockh); + + int (*moo_file_lock)(const struct lu_env *env, struct md_object *obj, + struct lov_mds_md *lmm, struct ldlm_extent *extent, + struct lustre_handle *lockh); + int (*moo_file_unlock)(const struct lu_env *env, struct md_object *obj, + struct lov_mds_md *lmm, + struct lustre_handle *lockh); + int (*moo_object_lock)(const struct lu_env *env, struct md_object *obj, + struct lustre_handle *lh, + struct ldlm_enqueue_info *einfo, + union ldlm_policy_data *policy); + int (*moo_object_unlock)(const struct lu_env *env, + struct md_object *obj, + struct ldlm_enqueue_info *einfo, + union ldlm_policy_data *policy); }; /** @@ -328,10 +296,13 @@ struct md_dir_operations { struct md_object *src_obj, const struct lu_name *lname, struct md_attr *ma); - int (*mdo_unlink)(const struct lu_env *env, struct md_object *pobj, - struct md_object *cobj, const struct lu_name *lname, - struct md_attr *ma); + int (*mdo_unlink)(const struct lu_env *env, struct md_object *pobj, + struct md_object *cobj, const struct lu_name *lname, + struct md_attr *ma, int no_name); + int (*mdo_migrate)(const struct lu_env *env, struct md_object *pobj, + struct md_object *sobj, const struct lu_name *lname, + struct md_object *tobj, struct md_attr *ma); /** This method is used to compare a requested layout to an existing * layout (struct lov_mds_md_v1/3 vs struct lov_mds_md_v1/3) */ int (*mdo_lum_lmm_cmp)(const struct lu_env *env, @@ -358,14 +329,14 @@ struct md_dir_operations { struct md_device_operations { /** meta-data device related handlers. */ - int (*mdo_root_get)(const struct lu_env *env, struct md_device *m, - struct lu_fid *f); + int (*mdo_root_get)(const struct lu_env *env, struct md_device *m, + struct lu_fid *f); - int (*mdo_maxsize_get)(const struct lu_env *env, struct md_device *m, - int *md_size, int *cookie_size); + int (*mdo_maxeasize_get)(const struct lu_env *env, struct md_device *m, + int *easize); int (*mdo_statfs)(const struct lu_env *env, struct md_device *m, - cfs_kstatfs_t *sfs); + struct obd_statfs *sfs); int (*mdo_init_capa_ctxt)(const struct lu_env *env, struct md_device *m, int mode, unsigned long timeout, __u32 alg, @@ -380,79 +351,6 @@ struct md_device_operations { int (*mdo_iocontrol)(const struct lu_env *env, struct md_device *m, unsigned int cmd, int len, void *data); - -#ifdef HAVE_QUOTA_SUPPORT - struct md_quota_operations { - int (*mqo_notify)(const struct lu_env *env, - struct md_device *m); - - int (*mqo_setup)(const struct lu_env *env, - struct md_device *m, - void *data); - - int (*mqo_cleanup)(const struct lu_env *env, - struct md_device *m); - - int (*mqo_recovery)(const struct lu_env *env, - struct md_device *m); - - int (*mqo_check)(const struct lu_env *env, - struct md_device *m, - __u32 type); - - int (*mqo_on)(const struct lu_env *env, - struct md_device *m, - __u32 type); - - int (*mqo_off)(const struct lu_env *env, - struct md_device *m, - __u32 type); - - int (*mqo_setinfo)(const struct lu_env *env, - struct md_device *m, - __u32 type, - __u32 id, - struct obd_dqinfo *dqinfo); - - int (*mqo_getinfo)(const struct lu_env *env, - const struct md_device *m, - __u32 type, - __u32 id, - struct obd_dqinfo *dqinfo); - - int (*mqo_setquota)(const struct lu_env *env, - struct md_device *m, - __u32 type, - __u32 id, - struct obd_dqblk *dqblk); - - int (*mqo_getquota)(const struct lu_env *env, - const struct md_device *m, - __u32 type, - __u32 id, - struct obd_dqblk *dqblk); - - int (*mqo_getoinfo)(const struct lu_env *env, - const struct md_device *m, - __u32 type, - __u32 id, - struct obd_dqinfo *dqinfo); - - int (*mqo_getoquota)(const struct lu_env *env, - const struct md_device *m, - __u32 type, - __u32 id, - struct obd_dqblk *dqblk); - - int (*mqo_invalidate)(const struct lu_env *env, - struct md_device *m, - __u32 type); - - int (*mqo_finvalidate)(const struct lu_env *env, - struct md_device *m, - __u32 type); - } mdo_quota; -#endif }; enum md_upcall_event { @@ -468,7 +366,7 @@ enum md_upcall_event { struct md_upcall { /** this lock protects upcall using against its removal * read lock is for usage the upcall, write - for init/fini */ - cfs_rw_semaphore_t mu_upcall_sem; + struct rw_semaphore mu_upcall_sem; /** device to call, upper layer normally */ struct md_device *mu_upcall_dev; /** upcall function */ @@ -484,39 +382,39 @@ struct md_device { static inline void md_upcall_init(struct md_device *m, void *upcl) { - cfs_init_rwsem(&m->md_upcall.mu_upcall_sem); - m->md_upcall.mu_upcall_dev = NULL; - m->md_upcall.mu_upcall = upcl; + init_rwsem(&m->md_upcall.mu_upcall_sem); + m->md_upcall.mu_upcall_dev = NULL; + m->md_upcall.mu_upcall = upcl; } static inline void md_upcall_dev_set(struct md_device *m, struct md_device *up) { - cfs_down_write(&m->md_upcall.mu_upcall_sem); - m->md_upcall.mu_upcall_dev = up; - cfs_up_write(&m->md_upcall.mu_upcall_sem); + down_write(&m->md_upcall.mu_upcall_sem); + m->md_upcall.mu_upcall_dev = up; + up_write(&m->md_upcall.mu_upcall_sem); } static inline void md_upcall_fini(struct md_device *m) { - cfs_down_write(&m->md_upcall.mu_upcall_sem); - m->md_upcall.mu_upcall_dev = NULL; - m->md_upcall.mu_upcall = NULL; - cfs_up_write(&m->md_upcall.mu_upcall_sem); + down_write(&m->md_upcall.mu_upcall_sem); + m->md_upcall.mu_upcall_dev = NULL; + m->md_upcall.mu_upcall = NULL; + up_write(&m->md_upcall.mu_upcall_sem); } static inline int md_do_upcall(const struct lu_env *env, struct md_device *m, - enum md_upcall_event ev, void *data) -{ - int rc = 0; - cfs_down_read(&m->md_upcall.mu_upcall_sem); - if (m->md_upcall.mu_upcall_dev != NULL && - m->md_upcall.mu_upcall_dev->md_upcall.mu_upcall != NULL) { - rc = m->md_upcall.mu_upcall_dev->md_upcall.mu_upcall(env, - m->md_upcall.mu_upcall_dev, - ev, data); - } - cfs_up_read(&m->md_upcall.mu_upcall_sem); - return rc; + enum md_upcall_event ev, void *data) +{ + int rc = 0; + down_read(&m->md_upcall.mu_upcall_sem); + if (m->md_upcall.mu_upcall_dev != NULL && + m->md_upcall.mu_upcall_dev->md_upcall.mu_upcall != NULL) { + rc = m->md_upcall.mu_upcall_dev->md_upcall.mu_upcall(env, + m->md_upcall.mu_upcall_dev, + ev, data); + } + up_read(&m->md_upcall.mu_upcall_sem); + return rc; } struct md_object { @@ -525,43 +423,46 @@ struct md_object { const struct md_dir_operations *mo_dir_ops; }; +/* Mark the object to be dead, and can not be accessed anymore. + * XXX, right now, it will only be used for striped directory to + * mark the slave stripes dead, when deleting master object. It will be + * stored in slave LMV EA (see lod_mark_dead_object), which is only + * temporary, and will be removed later when we have proper way to mark + * the dead object. */ +#define LUSTRE_SLAVE_DEAD_FL 0x80000000 + /** - * md-server site. + * seq-server site. */ -struct md_site { - struct lu_site ms_lu; - /** - * mds number of this site. - */ - mdsno_t ms_node_id; - /** - * Fid location database - */ - struct lu_server_fld *ms_server_fld; - struct lu_client_fld *ms_client_fld; - - /** - * Server Seq Manager - */ - struct lu_server_seq *ms_server_seq; - - /** - * Controller Seq Manager - */ - struct lu_server_seq *ms_control_seq; - struct obd_export *ms_control_exp; - - /** - * Client Seq Manager - */ - struct lu_client_seq *ms_client_seq; +struct seq_server_site { + struct lu_site *ss_lu; + /** + * mds number of this site. + */ + mdsno_t ss_node_id; + /** + * Fid location database + */ + struct lu_server_fld *ss_server_fld; + struct lu_client_fld *ss_client_fld; + + /** + * Server Seq Manager + */ + struct lu_server_seq *ss_server_seq; + + /** + * Controller Seq Manager + */ + struct lu_server_seq *ss_control_seq; + struct obd_export *ss_control_exp; + + /** + * Client Seq Manager + */ + struct lu_client_seq *ss_client_seq; }; -static inline int lu_device_is_md(const struct lu_device *d) -{ - return ergo(d != NULL, d->ld_type->ldt_tags & LU_DEVICE_MD); -} - static inline struct md_device *lu2md_dev(const struct lu_device *d) { LASSERT(IS_ERR(d) || lu_device_is_md(d)); @@ -584,17 +485,6 @@ static inline struct md_object *md_object_next(const struct md_object *obj) return (obj ? lu2md(lu_object_next(&obj->mo_lu)) : NULL); } -static inline struct md_device *md_obj2dev(const struct md_object *o) -{ - LASSERT(o == NULL || IS_ERR(o) || lu_device_is_md(o->mo_lu.lo_dev)); - return container_of0(o->mo_lu.lo_dev, struct md_device, md_lu_dev); -} - -static inline struct md_site *lu_site2md(const struct lu_site *s) -{ - return container_of0(s, struct md_site, ms_lu); -} - static inline int md_device_init(struct md_device *md, struct lu_device_type *t) { return lu_device_init(&md->md_lu_dev, t); @@ -691,6 +581,17 @@ static inline int mo_xattr_list(const struct lu_env *env, return m->mo_ops->moo_xattr_list(env, m, buf); } +static inline int mo_swap_layouts(const struct lu_env *env, + struct md_object *o1, + struct md_object *o2, __u64 flags) +{ + LASSERT(o1->mo_ops->moo_swap_layouts); + LASSERT(o2->mo_ops->moo_swap_layouts); + if (o1->mo_ops->moo_swap_layouts != o2->mo_ops->moo_swap_layouts) + return -EPERM; + return o1->mo_ops->moo_swap_layouts(env, o1, o2, flags); +} + static inline int mo_open(const struct lu_env *env, struct md_object *m, int flags) @@ -750,14 +651,6 @@ static inline int mo_capa_get(const struct lu_env *env, return m->mo_ops->moo_capa_get(env, m, c, renewal); } -static inline int mo_path(const struct lu_env *env, struct md_object *m, - char *path, int pathlen, __u64 *recno, int *linkno) -{ - if (m->mo_ops->moo_path == NULL) - return -ENOSYS; - return m->mo_ops->moo_path(env, m, path, pathlen, recno, linkno); -} - static inline int mo_object_sync(const struct lu_env *env, struct md_object *m) { LASSERT(m->mo_ops->moo_object_sync); @@ -781,6 +674,25 @@ static inline int mo_file_unlock(const struct lu_env *env, struct md_object *m, return m->mo_ops->moo_file_unlock(env, m, lmm, lockh); } +static inline int mo_object_lock(const struct lu_env *env, + struct md_object *m, + struct lustre_handle *lh, + struct ldlm_enqueue_info *einfo, + union ldlm_policy_data *policy) +{ + LASSERT(m->mo_ops->moo_object_lock); + return m->mo_ops->moo_object_lock(env, m, lh, einfo, policy); +} + +static inline int mo_object_unlock(const struct lu_env *env, + struct md_object *m, + struct ldlm_enqueue_info *einfo, + union ldlm_policy_data *policy) +{ + LASSERT(m->mo_ops->moo_object_unlock); + return m->mo_ops->moo_object_unlock(env, m, einfo, policy); +} + static inline int mdo_lookup(const struct lu_env *env, struct md_object *p, const struct lu_name *lname, @@ -807,8 +719,8 @@ static inline int mdo_create(const struct lu_env *env, struct md_op_spec *spc, struct md_attr *at) { - LASSERT(c->mo_dir_ops->mdo_create); - return c->mo_dir_ops->mdo_create(env, p, lchild_name, c, spc, at); + LASSERT(p->mo_dir_ops->mdo_create); + return p->mo_dir_ops->mdo_create(env, p, lchild_name, c, spc, at); } static inline int mdo_create_data(const struct lu_env *env, @@ -835,6 +747,17 @@ static inline int mdo_rename(const struct lu_env *env, ma); } +static inline int mdo_migrate(const struct lu_env *env, + struct md_object *pobj, + struct md_object *sobj, + const struct lu_name *lname, + struct md_object *tobj, + struct md_attr *ma) +{ + LASSERT(pobj->mo_dir_ops->mdo_migrate); + return pobj->mo_dir_ops->mdo_migrate(env, pobj, sobj, lname, tobj, ma); +} + static inline int mdo_is_subdir(const struct lu_env *env, struct md_object *mo, const struct lu_fid *fid, @@ -855,13 +778,13 @@ static inline int mdo_link(const struct lu_env *env, } static inline int mdo_unlink(const struct lu_env *env, - struct md_object *p, - struct md_object *c, - const struct lu_name *lname, - struct md_attr *ma) + struct md_object *p, + struct md_object *c, + const struct lu_name *lname, + struct md_attr *ma, int no_name) { - LASSERT(c->mo_dir_ops->mdo_unlink); - return c->mo_dir_ops->mdo_unlink(env, p, c, lname, ma); + LASSERT(p->mo_dir_ops->mdo_unlink); + return p->mo_dir_ops->mdo_unlink(env, p, c, lname, ma, no_name); } static inline int mdo_lum_lmm_cmp(const struct lu_env *env, @@ -908,6 +831,17 @@ static inline int mdo_rename_tgt(const struct lu_env *env, } } +/** + * Used in MDD/OUT layer for object lock rule + **/ +enum mdd_object_role { + MOR_SRC_PARENT, + MOR_SRC_CHILD, + MOR_TGT_PARENT, + MOR_TGT_CHILD, + MOR_TGT_ORPHAN +}; + struct dt_device; /** * Structure to hold object information. This is used to create object @@ -919,43 +853,60 @@ struct lu_local_obj_desc { __u32 llod_oid; int llod_is_index; const struct dt_index_features *llod_feat; - cfs_list_t llod_linkage; + struct list_head llod_linkage; +}; + +int lustre_buf2som(void *buf, int rc, struct md_som_data *msd); +int lustre_buf2hsm(void *buf, int rc, struct md_hsm *mh); +void lustre_hsm2buf(void *buf, const struct md_hsm *mh); + +enum { + UCRED_INVALID = -1, + UCRED_INIT = 0, + UCRED_OLD = 1, + UCRED_NEW = 2, +}; + +struct lu_ucred { + __u32 uc_valid; + __u32 uc_o_uid; + __u32 uc_o_gid; + __u32 uc_o_fsuid; + __u32 uc_o_fsgid; + __u32 uc_uid; + __u32 uc_gid; + __u32 uc_fsuid; + __u32 uc_fsgid; + __u32 uc_suppgids[2]; + cfs_cap_t uc_cap; + __u32 uc_umask; + struct group_info *uc_ginfo; + struct md_identity *uc_identity; }; -struct md_object *llo_store_resolve(const struct lu_env *env, - struct md_device *md, - struct dt_device *dt, - const char *path, - struct lu_fid *fid); - -struct md_object *llo_store_open(const struct lu_env *env, - struct md_device *md, - struct dt_device *dt, - const char *dirname, - const char *objname, - struct lu_fid *fid); - -struct md_object *llo_store_create_index(const struct lu_env *env, - struct md_device *md, - struct dt_device *dt, - const char *dirname, - const char *objname, - const struct lu_fid *fid, - const struct dt_index_features *feat); - -struct md_object *llo_store_create(const struct lu_env *env, - struct md_device *md, - struct dt_device *dt, - const char *dirname, - const char *objname, - const struct lu_fid *fid); - -void llo_local_obj_register(struct lu_local_obj_desc *); -void llo_local_obj_unregister(struct lu_local_obj_desc *); - -int llo_local_objects_setup(const struct lu_env *env, - struct md_device * md, - struct dt_device * dt); +struct lu_ucred *lu_ucred(const struct lu_env *env); + +struct lu_ucred *lu_ucred_check(const struct lu_env *env); + +struct lu_ucred *lu_ucred_assert(const struct lu_env *env); + +int lu_ucred_global_init(void); + +void lu_ucred_global_fini(void); + +#define md_cap_t(x) (x) + +#define MD_CAP_TO_MASK(x) (1 << (x)) + +#define md_cap_raised(c, flag) (md_cap_t(c) & MD_CAP_TO_MASK(flag)) + +/* capable() is copied from linux kernel! */ +static inline int md_capable(struct lu_ucred *uc, cfs_cap_t cap) +{ + if (md_cap_raised(uc->uc_cap, cap)) + return 1; + return 0; +} /** @} md */ #endif /* _LINUX_MD_OBJECT_H */