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 struct exofs_dev {
  57         struct ore_dev ored;
  58         unsigned did;
  59 };
  60 /*
  61  * our extension to the in-memory superblock
  62  */
  63 struct exofs_sb_info {
  64         struct backing_dev_info bdi;            /* register our bdi with VFS  */
  65         struct exofs_sb_stats s_ess;            /* Written often, pre-allocate*/
  66         int             s_timeout;              /* timeout for OSD operations */
  67         uint64_t        s_nextid;               /* highest object ID used     */
  68         uint32_t        s_numfiles;             /* number of files on fs      */
  69         spinlock_t      s_next_gen_lock;        /* spinlock for gen # update  */
  70         u32             s_next_generation;      /* next gen # to use          */
  71         atomic_t        s_curr_pending;         /* number of pending commands */
  72
  73         struct ore_layout       layout;         /* Default files layout       */
  74         struct ore_comp one_comp;               /* id & cred of partition id=0*/
  75         struct ore_components oc;               /* comps for the partition    */
  76 };
  77
  78 /*
  79  * our extension to the in-memory inode
  80  */
  81 struct exofs_i_info {
  82         struct inode   vfs_inode;          /* normal in-memory inode          */
  83         wait_queue_head_t i_wq;            /* wait queue for inode            */
  84         unsigned long  i_flags;            /* various atomic flags            */
  85         uint32_t       i_data[EXOFS_IDATA];/*short symlink names and device #s*/
  86         uint32_t       i_dir_start_lookup; /* which page to start lookup      */
  87         uint64_t       i_commit_size;      /* the object's written length     */
  88         struct ore_comp one_comp;          /* same component for all devices  */
  89         struct ore_components oc;          /* inode view of the device table  */
  90 };
  91
  92 static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
  93 {
  94         return oi->vfs_inode.i_ino + EXOFS_OBJ_OFF;
  95 }
  96
  97 /*
  98  * our inode flags
  99  */
 100 #define OBJ_2BCREATED   0       /* object will be created soon*/
 101 #define OBJ_CREATED     1       /* object has been created on the osd*/
 102
 103 static inline int obj_2bcreated(struct exofs_i_info *oi)
 104 {
 105         return test_bit(OBJ_2BCREATED, &oi->i_flags);
 106 }
 107
 108 static inline void set_obj_2bcreated(struct exofs_i_info *oi)
 109 {
 110         set_bit(OBJ_2BCREATED, &oi->i_flags);
 111 }
 112
 113 static inline int obj_created(struct exofs_i_info *oi)
 114 {
 115         return test_bit(OBJ_CREATED, &oi->i_flags);
 116 }
 117
 118 static inline void set_obj_created(struct exofs_i_info *oi)
 119 {
 120         set_bit(OBJ_CREATED, &oi->i_flags);
 121 }
 122
 123 int __exofs_wait_obj_created(struct exofs_i_info *oi);
 124 static inline int wait_obj_created(struct exofs_i_info *oi)
 125 {
 126         if (likely(obj_created(oi)))
 127                 return 0;
 128
 129         return __exofs_wait_obj_created(oi);
 130 }
 131
 132 /*
 133  * get to our inode from the vfs inode
 134  */
 135 static inline struct exofs_i_info *exofs_i(struct inode *inode)
 136 {
 137         return container_of(inode, struct exofs_i_info, vfs_inode);
 138 }
 139
 140 /*
 141  * Maximum count of links to a file
 142  */
 143 #define EXOFS_LINK_MAX           32000
 144
 145 /*************************
 146  * function declarations *
 147  *************************/
 148
 149 /* inode.c               */
 150 unsigned exofs_max_io_pages(struct ore_layout *layout,
 151                             unsigned expected_pages);
 152 int exofs_setattr(struct dentry *, struct iattr *);
 153 int exofs_write_begin(struct file *file, struct address_space *mapping,
 154                 loff_t pos, unsigned len, unsigned flags,
 155                 struct page **pagep, void **fsdata);
 156 extern struct inode *exofs_iget(struct super_block *, unsigned long);
 157 struct inode *exofs_new_inode(struct inode *, umode_t);
 158 extern int exofs_write_inode(struct inode *, struct writeback_control *wbc);
 159 extern void exofs_evict_inode(struct inode *);
 160
 161 /* dir.c:                */
 162 int exofs_add_link(struct dentry *, struct inode *);
 163 ino_t exofs_inode_by_name(struct inode *, struct dentry *);
 164 int exofs_delete_entry(struct exofs_dir_entry *, struct page *);
 165 int exofs_make_empty(struct inode *, struct inode *);
 166 struct exofs_dir_entry *exofs_find_entry(struct inode *, struct dentry *,
 167                                          struct page **);
 168 int exofs_empty_dir(struct inode *);
 169 struct exofs_dir_entry *exofs_dotdot(struct inode *, struct page **);
 170 ino_t exofs_parent_ino(struct dentry *child);
 171 int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
 172                     struct inode *);
 173
 174 /* super.c               */
 175 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
 176                            const struct osd_obj_id *obj);
 177 int exofs_sbi_write_stats(struct exofs_sb_info *sbi);
 178
 179 /*********************
 180  * operation vectors *
 181  *********************/
 182 /* dir.c:            */
 183 extern const struct file_operations exofs_dir_operations;
 184
 185 /* file.c            */
 186 extern const struct inode_operations exofs_file_inode_operations;
 187 extern const struct file_operations exofs_file_operations;
 188
 189 /* inode.c           */
 190 extern const struct address_space_operations exofs_aops;
 191
 192 /* namei.c           */
 193 extern const struct inode_operations exofs_dir_inode_operations;
 194 extern const struct inode_operations exofs_special_inode_operations;
 195
 196 /* symlink.c         */
 197 extern const struct inode_operations exofs_symlink_inode_operations;
 198 extern const struct inode_operations exofs_fast_symlink_inode_operations;
 199
 200 /* exofs_init_comps will initialize an ore_components device array
 201  * pointing to a single ore_comp struct, and a round-robin view
 202  * of the device table.
 203  * The first device of each inode is the [inode->ino % num_devices]
 204  * and the rest of the devices sequentially following where the
 205  * first device is after the last device.
 206  * It is assumed that the global device array at @sbi is twice
 207  * bigger and that the device table repeats twice.
 208  * See: exofs_read_lookup_dev_table()
 209  */
 210 static inline void exofs_init_comps(struct ore_components *oc,
 211                                     struct ore_comp *one_comp,
 212                                     struct exofs_sb_info *sbi, osd_id oid)
 213 {
 214         unsigned dev_mod = (unsigned)oid, first_dev;
 215
 216         one_comp->obj.partition = sbi->one_comp.obj.partition;
 217         one_comp->obj.id = oid;
 218         exofs_make_credential(one_comp->cred, &one_comp->obj);
 219
 220         oc->first_dev = 0;
 221         oc->numdevs = sbi->layout.group_width * sbi->layout.mirrors_p1 *
 222                                                         sbi->layout.group_count;
 223         oc->single_comp = EC_SINGLE_COMP;
 224         oc->comps = one_comp;
 225
 226         /* Round robin device view of the table */
 227         first_dev = (dev_mod * sbi->layout.mirrors_p1) % sbi->oc.numdevs;
 228         oc->ods = &sbi->oc.ods[first_dev];
 229 }
 230
 231 #endif