drivers/staging/lustre/lustre/include/lustre_lite.h

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #ifndef _LL_H
  38 #define _LL_H
  39
  40 /** \defgroup lite lite
  41  *
  42  * @{
  43  */
  44
  45 #include "linux/lustre_lite.h"
  46
  47 #include "obd_class.h"
  48 #include "obd_ost.h"
  49 #include "lustre_net.h"
  50 #include "lustre_mds.h"
  51 #include "lustre_ha.h"
  52
  53 /* 4UL * 1024 * 1024 */
  54 #define LL_MAX_BLKSIZE_BITS     (22)
  55 #define LL_MAX_BLKSIZE    (1UL<<LL_MAX_BLKSIZE_BITS)
  56
  57 #include "lustre/lustre_user.h"
  58
  59
  60 struct lustre_rw_params {
  61         int             lrp_lock_mode;
  62         ldlm_policy_data_t lrp_policy;
  63         u32             lrp_brw_flags;
  64         int             lrp_ast_flags;
  65 };
  66
  67 /*
  68  * XXX nikita: this function lives in the header because it is used by both
  69  * llite kernel module and liblustre library, and there is no (?) better place
  70  * to put it in.
  71  */
  72 static inline void lustre_build_lock_params(int cmd, unsigned long open_flags,
  73                                             __u64 connect_flags,
  74                                             loff_t pos, ssize_t len,
  75                                             struct lustre_rw_params *params)
  76 {
  77         params->lrp_lock_mode = (cmd == OBD_BRW_READ) ? LCK_PR : LCK_PW;
  78         params->lrp_brw_flags = 0;
  79
  80         params->lrp_policy.l_extent.start = pos;
  81         params->lrp_policy.l_extent.end = pos + len - 1;
  82         /*
  83          * for now O_APPEND always takes local locks.
  84          */
  85         if (cmd == OBD_BRW_WRITE && (open_flags & O_APPEND)) {
  86                 params->lrp_policy.l_extent.start = 0;
  87                 params->lrp_policy.l_extent.end   = OBD_OBJECT_EOF;
  88         } else if (LIBLUSTRE_CLIENT && (connect_flags & OBD_CONNECT_SRVLOCK)) {
  89                 /*
  90                  * liblustre: OST-side locking for all non-O_APPEND
  91                  * reads/writes.
  92                  */
  93                 params->lrp_lock_mode = LCK_NL;
  94                 params->lrp_brw_flags = OBD_BRW_SRVLOCK;
  95         } else {
  96                 /*
  97                  * nothing special for the kernel. In the future llite may use
  98                  * OST-side locks for small writes into highly contended
  99                  * files.
 100                  */
 101         }
 102         params->lrp_ast_flags = (open_flags & O_NONBLOCK) ?
 103                 LDLM_FL_BLOCK_NOWAIT : 0;
 104 }
 105
 106 /*
 107  * This is embedded into liblustre and llite super-blocks to keep track of
 108  * connect flags (capabilities) supported by all imports given mount is
 109  * connected to.
 110  */
 111 struct lustre_client_ocd {
 112         /*
 113          * This is conjunction of connect_flags across all imports (LOVs) this
 114          * mount is connected to. This field is updated by cl_ocd_update()
 115          * under ->lco_lock.
 116          */
 117         __u64         lco_flags;
 118         struct mutex       lco_lock;
 119         struct obd_export *lco_md_exp;
 120         struct obd_export *lco_dt_exp;
 121 };
 122
 123 /*
 124  * Chain of hash overflow pages.
 125  */
 126 struct ll_dir_chain {
 127         /* XXX something. Later */
 128 };
 129
 130 static inline void ll_dir_chain_init(struct ll_dir_chain *chain)
 131 {
 132 }
 133
 134 static inline void ll_dir_chain_fini(struct ll_dir_chain *chain)
 135 {
 136 }
 137
 138 static inline unsigned long hash_x_index(__u64 hash, int hash64)
 139 {
 140         if (BITS_PER_LONG == 32 && hash64)
 141                 hash >>= 32;
 142         /* save hash 0 as index 0 because otherwise we'll save it at
 143          * page index end (~0UL) and it causes truncate_inode_pages_range()
 144          * to loop forever.
 145          */
 146         return ~0UL - (hash + !hash);
 147 }
 148
 149 /** @} lite */
 150
 151 #endif