fs/exofs/exofs.h

   1 /*
   2  * Copyright (C) 2005, 2006
   3  * Avishay Traeger (avishay@gmail.com)
   4  * Copyright (C) 2008, 2009
   5  * Boaz Harrosh <bharrosh@panasas.com>
   6  *
   7  * Copyrights for code taken from ext2:
   8  *     Copyright (C) 1992, 1993, 1994, 1995
   9  *     Remy Card (card@masi.ibp.fr)
  10  *     Laboratoire MASI - Institut Blaise Pascal
  11  *     Universite Pierre et Marie Curie (Paris VI)
  12  *     from
  13  *     linux/fs/minix/inode.c
  14  *     Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  * This file is part of exofs.
  17  *
  18  * exofs is free software; you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation.  Since it is based on ext2, and the only
  21  * valid version of GPL for the Linux kernel is version 2, the only valid
  22  * version of GPL for exofs is version 2.
  23  *
  24  * exofs is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with exofs; if not, write to the Free Software
  31  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  32  */
  33 #ifndef __EXOFS_H__
  34 #define __EXOFS_H__
  35
  36 #include <linux/fs.h>
  37 #include <linux/time.h>
  38 #include <linux/backing-dev.h>
  39 #include <scsi/osd_ore.h>
  40
  41 #include "common.h"
  42
  43 #define EXOFS_ERR(fmt, a...) printk(KERN_ERR "exofs: " fmt, ##a)
  44
  45 #ifdef CONFIG_EXOFS_DEBUG
  46 #define EXOFS_DBGMSG(fmt, a...) \
  47         printk(KERN_NOTICE "exofs @%s:%d: " fmt, __func__, __LINE__, ##a)
  48 #else
  49 #define EXOFS_DBGMSG(fmt, a...) \
  50         do { if (0) printk(fmt, ##a); } while (0)
  51 #endif
  52
  53 /* u64 has problems with printk this will cast it to unsigned long long */
  54 #define _LLU(x) (unsigned long long)(x)
  55
  56 /*
  57  * our extension to the in-memory superblock
  58  */
  59 struct exofs_sb_info {
  60         struct backing_dev_info bdi;            /* register our bdi with VFS  */
  61         struct exofs_sb_stats s_ess;            /* Written often, pre-allocate*/
  62         int             s_timeout;              /* timeout for OSD operations */
  63         uint64_t        s_nextid;               /* highest object ID used     */
  64         uint32_t        s_numfiles;             /* number of files on fs      */
  65         spinlock_t      s_next_gen_lock;        /* spinlock for gen # update  */
  66         u32             s_next_generation;      /* next gen # to use          */
  67         atomic_t        s_curr_pending;         /* number of pending commands */
  68
  69         struct ore_layout       layout;         /* Default files layout       */
  70         struct ore_comp one_comp;               /* id & cred of partition id=0*/
  71         struct ore_components comps;            /* comps for the partition    */
  72         struct osd_dev  *_min_one_dev[1];       /* Place holder for one dev   */
  73 };
  74
  75 /*
  76  * our extension to the in-memory inode
  77  */
  78 struct exofs_i_info {
  79         struct inode   vfs_inode;          /* normal in-memory inode          */
  80         wait_queue_head_t i_wq;            /* wait queue for inode            */
  81         unsigned long  i_flags;            /* various atomic flags            */
  82         uint32_t       i_data[EXOFS_IDATA];/*short symlink names and device #s*/
  83         uint32_t       i_dir_start_lookup; /* which page to start lookup      */
  84         uint64_t       i_commit_size;      /* the object's written length     */
  85         struct ore_comp one_comp;          /* same component for all devices  */
  86         struct ore_components comps;       /* inode view of the device table  */
  87 };
  88
  89 static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
  90 {
  91         return oi->vfs_inode.i_ino + EXOFS_OBJ_OFF;
  92 }
  93
  94 /*
  95  * our inode flags
  96  */
  97 #define OBJ_2BCREATED   0       /* object will be created soon*/
  98 #define OBJ_CREATED     1       /* object has been created on the osd*/
  99
 100 static inline int obj_2bcreated(struct exofs_i_info *oi)
 101 {
 102         return test_bit(OBJ_2BCREATED, &oi->i_flags);
 103 }
 104
 105 static inline void set_obj_2bcreated(struct exofs_i_info *oi)
 106 {
 107         set_bit(OBJ_2BCREATED, &oi->i_flags);
 108 }
 109
 110 static inline int obj_created(struct exofs_i_info *oi)
 111 {
 112         return test_bit(OBJ_CREATED, &oi->i_flags);
 113 }
 114
 115 static inline void set_obj_created(struct exofs_i_info *oi)
 116 {
 117         set_bit(OBJ_CREATED, &oi->i_flags);
 118 }
 119
 120 int __exofs_wait_obj_created(struct exofs_i_info *oi);
 121 static inline int wait_obj_created(struct exofs_i_info *oi)
 122 {
 123         if (likely(obj_created(oi)))
 124                 return 0;
 125
 126         return __exofs_wait_obj_created(oi);
 127 }
 128
 129 /*
 130  * get to our inode from the vfs inode
 131  */
 132 static inline struct exofs_i_info *exofs_i(struct inode *inode)
 133 {
 134         return container_of(inode, struct exofs_i_info, vfs_inode);
 135 }
 136
 137 /*
 138  * Maximum count of links to a file
 139  */
 140 #define EXOFS_LINK_MAX           32000
 141
 142 /*************************
 143  * function declarations *
 144  *************************/
 145
 146 /* inode.c               */
 147 unsigned exofs_max_io_pages(struct ore_layout *layout,
 148                             unsigned expected_pages);
 149 int exofs_setattr(struct dentry *, struct iattr *);
 150 int exofs_write_begin(struct file *file, struct address_space *mapping,
 151                 loff_t pos, unsigned len, unsigned flags,
 152                 struct page **pagep, void **fsdata);
 153 extern struct inode *exofs_iget(struct super_block *, unsigned long);
 154 struct inode *exofs_new_inode(struct inode *, int);
 155 extern int exofs_write_inode(struct inode *, struct writeback_control *wbc);
 156 extern void exofs_evict_inode(struct inode *);
 157
 158 /* dir.c:                */
 159 int exofs_add_link(struct dentry *, struct inode *);
 160 ino_t exofs_inode_by_name(struct inode *, struct dentry *);
 161 int exofs_delete_entry(struct exofs_dir_entry *, struct page *);
 162 int exofs_make_empty(struct inode *, struct inode *);
 163 struct exofs_dir_entry *exofs_find_entry(struct inode *, struct dentry *,
 164                                          struct page **);
 165 int exofs_empty_dir(struct inode *);
 166 struct exofs_dir_entry *exofs_dotdot(struct inode *, struct page **);
 167 ino_t exofs_parent_ino(struct dentry *child);
 168 int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
 169                     struct inode *);
 170
 171 /* super.c               */
 172 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
 173                            const struct osd_obj_id *obj);
 174 int exofs_sbi_write_stats(struct exofs_sb_info *sbi);
 175
 176 /*********************
 177  * operation vectors *
 178  *********************/
 179 /* dir.c:            */
 180 extern const struct file_operations exofs_dir_operations;
 181
 182 /* file.c            */
 183 extern const struct inode_operations exofs_file_inode_operations;
 184 extern const struct file_operations exofs_file_operations;
 185
 186 /* inode.c           */
 187 extern const struct address_space_operations exofs_aops;
 188
 189 /* namei.c           */
 190 extern const struct inode_operations exofs_dir_inode_operations;
 191 extern const struct inode_operations exofs_special_inode_operations;
 192
 193 /* symlink.c         */
 194 extern const struct inode_operations exofs_symlink_inode_operations;
 195 extern const struct inode_operations exofs_fast_symlink_inode_operations;
 196
 197 /* exofs_init_comps will initialize an ore_components device array
 198  * pointing to a single ore_comp struct, and a round-robin view
 199  * of the device table.
 200  * The first device of each inode is the [inode->ino % num_devices]
 201  * and the rest of the devices sequentially following where the
 202  * first device is after the last device.
 203  * It is assumed that the global device array at @sbi is twice
 204  * bigger and that the device table repeats twice.
 205  * See: exofs_read_lookup_dev_table()
 206  */
 207 static inline void exofs_init_comps(struct ore_components *comps,
 208                                     struct ore_comp *one_comp,
 209                                     struct exofs_sb_info *sbi, osd_id oid)
 210 {
 211         unsigned dev_mod = (unsigned)oid, first_dev;
 212
 213         one_comp->obj.partition = sbi->one_comp.obj.partition;
 214         one_comp->obj.id = oid;
 215         exofs_make_credential(one_comp->cred, &one_comp->obj);
 216
 217         comps->numdevs = sbi->comps.numdevs;
 218         comps->single_comp = EC_SINGLE_COMP;
 219         comps->comps = one_comp;
 220
 221         /* Round robin device view of the table */
 222         first_dev = (dev_mod * sbi->layout.mirrors_p1) % sbi->comps.numdevs;
 223         comps->ods = sbi->comps.ods + first_dev;
 224 }
 225
 226 #endif