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         unsigned urilen;
  60         uint8_t *uri;
  61         struct kobject ed_kobj;
  62 };
  63 /*
  64  * our extension to the in-memory superblock
  65  */
  66 struct exofs_sb_info {
  67         struct backing_dev_info bdi;            /* register our bdi with VFS  */
  68         struct exofs_sb_stats s_ess;            /* Written often, pre-allocate*/
  69         int             s_timeout;              /* timeout for OSD operations */
  70         uint64_t        s_nextid;               /* highest object ID used     */
  71         uint32_t        s_numfiles;             /* number of files on fs      */
  72         spinlock_t      s_next_gen_lock;        /* spinlock for gen # update  */
  73         u32             s_next_generation;      /* next gen # to use          */
  74         atomic_t        s_curr_pending;         /* number of pending commands */
  75
  76         struct ore_layout       layout;         /* Default files layout       */
  77         struct ore_comp one_comp;               /* id & cred of partition id=0*/
  78         struct ore_components oc;               /* comps for the partition    */
  79         struct kobject  s_kobj;                 /* holds per-sbi kobject      */
  80 };
  81
  82 /*
  83  * our extension to the in-memory inode
  84  */
  85 struct exofs_i_info {
  86         struct inode   vfs_inode;          /* normal in-memory inode          */
  87         wait_queue_head_t i_wq;            /* wait queue for inode            */
  88         unsigned long  i_flags;            /* various atomic flags            */
  89         uint32_t       i_data[EXOFS_IDATA];/*short symlink names and device #s*/
  90         uint32_t       i_dir_start_lookup; /* which page to start lookup      */
  91         uint64_t       i_commit_size;      /* the object's written length     */
  92         struct ore_comp one_comp;          /* same component for all devices  */
  93         struct ore_components oc;          /* inode view of the device table  */
  94 };
  95
  96 static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
  97 {
  98         return oi->vfs_inode.i_ino + EXOFS_OBJ_OFF;
  99 }
 100
 101 /*
 102  * our inode flags
 103  */
 104 #define OBJ_2BCREATED   0       /* object will be created soon*/
 105 #define OBJ_CREATED     1       /* object has been created on the osd*/
 106
 107 static inline int obj_2bcreated(struct exofs_i_info *oi)
 108 {
 109         return test_bit(OBJ_2BCREATED, &oi->i_flags);
 110 }
 111
 112 static inline void set_obj_2bcreated(struct exofs_i_info *oi)
 113 {
 114         set_bit(OBJ_2BCREATED, &oi->i_flags);
 115 }
 116
 117 static inline int obj_created(struct exofs_i_info *oi)
 118 {
 119         return test_bit(OBJ_CREATED, &oi->i_flags);
 120 }
 121
 122 static inline void set_obj_created(struct exofs_i_info *oi)
 123 {
 124         set_bit(OBJ_CREATED, &oi->i_flags);
 125 }
 126
 127 int __exofs_wait_obj_created(struct exofs_i_info *oi);
 128 static inline int wait_obj_created(struct exofs_i_info *oi)
 129 {
 130         if (likely(obj_created(oi)))
 131                 return 0;
 132
 133         return __exofs_wait_obj_created(oi);
 134 }
 135
 136 /*
 137  * get to our inode from the vfs inode
 138  */
 139 static inline struct exofs_i_info *exofs_i(struct inode *inode)
 140 {
 141         return container_of(inode, struct exofs_i_info, vfs_inode);
 142 }
 143
 144 /*
 145  * Maximum count of links to a file
 146  */
 147 #define EXOFS_LINK_MAX           32000
 148
 149 /*************************
 150  * function declarations *
 151  *************************/
 152
 153 /* inode.c               */
 154 unsigned exofs_max_io_pages(struct ore_layout *layout,
 155                             unsigned expected_pages);
 156 int exofs_setattr(struct dentry *, struct iattr *);
 157 int exofs_write_begin(struct file *file, struct address_space *mapping,
 158                 loff_t pos, unsigned len, unsigned flags,
 159                 struct page **pagep, void **fsdata);
 160 extern struct inode *exofs_iget(struct super_block *, unsigned long);
 161 struct inode *exofs_new_inode(struct inode *, umode_t);
 162 extern int exofs_write_inode(struct inode *, struct writeback_control *wbc);
 163 extern void exofs_evict_inode(struct inode *);
 164
 165 /* dir.c:                */
 166 int exofs_add_link(struct dentry *, struct inode *);
 167 ino_t exofs_inode_by_name(struct inode *, struct dentry *);
 168 int exofs_delete_entry(struct exofs_dir_entry *, struct page *);
 169 int exofs_make_empty(struct inode *, struct inode *);
 170 struct exofs_dir_entry *exofs_find_entry(struct inode *, struct dentry *,
 171                                          struct page **);
 172 int exofs_empty_dir(struct inode *);
 173 struct exofs_dir_entry *exofs_dotdot(struct inode *, struct page **);
 174 ino_t exofs_parent_ino(struct dentry *child);
 175 int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
 176                     struct inode *);
 177
 178 /* super.c               */
 179 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
 180                            const struct osd_obj_id *obj);
 181 int exofs_sbi_write_stats(struct exofs_sb_info *sbi);
 182
 183 /* sys.c                 */
 184 int exofs_sysfs_init(void);
 185 void exofs_sysfs_uninit(void);
 186 int exofs_sysfs_sb_add(struct exofs_sb_info *sbi,
 187                        struct exofs_dt_device_info *dt_dev);
 188 void exofs_sysfs_sb_del(struct exofs_sb_info *sbi);
 189 int exofs_sysfs_odev_add(struct exofs_dev *edev,
 190                          struct exofs_sb_info *sbi);
 191 void exofs_sysfs_dbg_print(void);
 192
 193 /*********************
 194  * operation vectors *
 195  *********************/
 196 /* dir.c:            */
 197 extern const struct file_operations exofs_dir_operations;
 198
 199 /* file.c            */
 200 extern const struct inode_operations exofs_file_inode_operations;
 201 extern const struct file_operations exofs_file_operations;
 202
 203 /* inode.c           */
 204 extern const struct address_space_operations exofs_aops;
 205
 206 /* namei.c           */
 207 extern const struct inode_operations exofs_dir_inode_operations;
 208 extern const struct inode_operations exofs_special_inode_operations;
 209
 210 /* symlink.c         */
 211 extern const struct inode_operations exofs_symlink_inode_operations;
 212 extern const struct inode_operations exofs_fast_symlink_inode_operations;
 213
 214 /* exofs_init_comps will initialize an ore_components device array
 215  * pointing to a single ore_comp struct, and a round-robin view
 216  * of the device table.
 217  * The first device of each inode is the [inode->ino % num_devices]
 218  * and the rest of the devices sequentially following where the
 219  * first device is after the last device.
 220  * It is assumed that the global device array at @sbi is twice
 221  * bigger and that the device table repeats twice.
 222  * See: exofs_read_lookup_dev_table()
 223  */
 224 static inline void exofs_init_comps(struct ore_components *oc,
 225                                     struct ore_comp *one_comp,
 226                                     struct exofs_sb_info *sbi, osd_id oid)
 227 {
 228         unsigned dev_mod = (unsigned)oid, first_dev;
 229
 230         one_comp->obj.partition = sbi->one_comp.obj.partition;
 231         one_comp->obj.id = oid;
 232         exofs_make_credential(one_comp->cred, &one_comp->obj);
 233
 234         oc->first_dev = 0;
 235         oc->numdevs = sbi->layout.group_width * sbi->layout.mirrors_p1 *
 236                                                         sbi->layout.group_count;
 237         oc->single_comp = EC_SINGLE_COMP;
 238         oc->comps = one_comp;
 239
 240         /* Round robin device view of the table */
 241         first_dev = (dev_mod * sbi->layout.mirrors_p1) % sbi->oc.numdevs;
 242         oc->ods = &sbi->oc.ods[first_dev];
 243 }
 244
 245 #endif