lustre/obdfs/super.c

   1 /*
   2  * OBDFS Super operations
   3  *
   4  * Copryright (C) 1996 Peter J. Braam <braam@stelias.com>
   5  * Copryright (C) 1999 Stelias Computing Inc. <braam@stelias.com>
   6  * Copryright (C) 1999 Seagate Technology Inc.
   7  *
   8  */
   9
  10 #define EXPORT_SYMTAB
  11
  12 #include <linux/config.h>
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mm.h>
  16 #include <linux/string.h>
  17 #include <linux/stat.h>
  18 #include <linux/errno.h>
  19 #include <linux/locks.h>
  20 #include <linux/unistd.h>
  21
  22 #include <asm/system.h>
  23 #include <asm/uaccess.h>
  24
  25 #include <linux/fs.h>
  26 #include <linux/stat.h>
  27 #include <asm/uaccess.h>
  28 #include <linux/vmalloc.h>
  29 #include <asm/segment.h>
  30
  31 #include <linux/obd_support.h>
  32 #include <linux/obd_class.h>
  33 #include <linux/obd_sim.h>  /* XXX for development/debugging only */
  34 #include <obdfs.h>
  35
  36 /* VFS super_block ops */
  37 static struct super_block *obdfs_read_super(struct super_block *, void *, int);
  38 static void obdfs_read_inode(struct inode *);
  39 static int  obdfs_notify_change(struct dentry *dentry, struct iattr *attr);
  40 static void obdfs_write_inode(struct inode *);
  41 static void obdfs_delete_inode(struct inode *);
  42 static void obdfs_put_super(struct super_block *);
  43 static int obdfs_statfs(struct super_block *sb, struct statfs *buf,
  44                        int bufsiz);
  45
  46 /* exported operations */
  47 struct super_operations obdfs_super_operations =
  48 {
  49         obdfs_read_inode,       /* read_inode */
  50         obdfs_write_inode,      /* write_inode */
  51         NULL,                   /* put_inode */
  52         obdfs_delete_inode,     /* delete_inode */
  53         obdfs_notify_change,    /* notify_change */
  54         obdfs_put_super,        /* put_super */
  55         NULL,                   /* write_super */
  56         obdfs_statfs,           /* statfs */
  57         NULL                    /* remount_fs */
  58 };
  59
  60 struct obdfs_sb_info obdfs_super_info;
  61 int obd_minor = 0;
  62 int obd_root_ino = 2;
  63
  64 static struct super_block * obdfs_read_super(struct super_block *sb,
  65                                             void *data, int silent)
  66 {
  67         struct inode *root = 0;
  68         struct obdfs_sb_info *sbi = NULL;
  69         struct obd_device *obddev;
  70         int error = 0;
  71         unsigned long blocksize;
  72         unsigned long blocksize_bits;
  73         unsigned long root_ino;
  74         int scratch;
  75
  76
  77         ENTRY;
  78         MOD_INC_USE_COUNT;
  79
  80         sbi = &obdfs_super_info;
  81
  82         if ( sbi->osi_super ) {
  83                 printk("Already mounted\n");
  84                 MOD_DEC_USE_COUNT;
  85                 return NULL;
  86         }
  87
  88         obddev = &obd_dev[obd_minor];
  89
  90         if ( ! (obddev->obd_flags & OBD_ATTACHED) ||
  91              ! (obddev->obd_flags & OBD_SET_UP) )
  92                 return NULL;
  93
  94         sbi->osi_obd = obddev;
  95         sbi->osi_ops = sbi->osi_obd->obd_type->typ_ops;
  96
  97         error  = sbi->osi_ops->o_connect(sbi->osi_obd, &sbi->osi_conn_info);
  98         if ( error ) {
  99                 printk("OBDFS: cannot connect to 0x%x.\n", obd_minor);
 100                 goto error;
 101         }
 102
 103         sbi->osi_super = sb;
 104
 105         error = sbi->osi_ops->o_get_info(sbi->osi_conn_info.conn_id,
 106                                          strlen("blocksize"),
 107                                          "blocksize",
 108                                          &scratch, (void *)&blocksize);
 109         if ( error ) {
 110                 printk("Getinfo call to drive failed (blocksize)\n");
 111                 goto error;
 112         }
 113
 114         error = sbi->osi_ops->o_get_info(sbi->osi_conn_info.conn_id,
 115                                          strlen("blocksize_bits"),
 116                                          "blocksize_bits",
 117                                          &scratch, (void *)&blocksize_bits);
 118         if ( error ) {
 119                 printk("Getinfo call to drive failed (blocksize_bits)\n");
 120                 goto error;
 121         }
 122
 123         error = sbi->osi_ops->o_get_info(sbi->osi_conn_info.conn_id,
 124                                          strlen("root_ino"),
 125                                          "root_ino",
 126                                          &scratch, (void *)&root_ino);
 127         if ( error ) {
 128                 printk("Getinfo call to drive failed (root_ino)\n");
 129                 goto error;
 130         }
 131
 132
 133         lock_super(sb);
 134         sb->u.generic_sbp = sbi;
 135
 136         sb->s_blocksize = blocksize;
 137         sb->s_blocksize_bits = (unsigned char)blocksize_bits;
 138         sb->s_magic = OBDFS_SUPER_MAGIC;
 139         sb->s_op = &obdfs_super_operations;
 140
 141         /* make root inode */
 142         root = iget(sb, root_ino);
 143         if (!root || is_bad_inode(root)) {
 144             printk("OBDFS: bad iget for root\n");
 145             sb->s_dev = 0;
 146             error = ENOENT;
 147             unlock_super(sb);
 148             goto error;
 149         }
 150
 151         printk("obdfs_read_super: rootinode is %ld dev %d\n",
 152                root->i_ino, root->i_dev);
 153         sb->s_root = d_alloc_root(root);
 154         unlock_super(sb);
 155         EXIT;
 156         return sb;
 157
 158  error:
 159         EXIT;
 160         MOD_DEC_USE_COUNT;
 161         if (sbi) {
 162                 sbi->osi_super = NULL;
 163         }
 164         if (root) {
 165                 iput(root);
 166         }
 167         sb->s_dev = 0;
 168         return NULL;
 169 }
 170
 171 static void obdfs_put_super(struct super_block *sb)
 172 {
 173         struct obdfs_sb_info *sbi;
 174
 175         ENTRY;
 176
 177
 178         sb->s_dev = 0;
 179
 180         /* XXX flush stuff */
 181         sbi = sb->u.generic_sbp;
 182         sb->u.generic_sbp = NULL;
 183         sbi->osi_ops->o_disconnect(sbi->osi_conn_info.conn_id);
 184         sbi->osi_super = NULL;
 185
 186
 187         printk("OBDFS: Bye bye.\n");
 188         memset(sbi, 0, sizeof(* sbi));
 189
 190         MOD_DEC_USE_COUNT;
 191         EXIT;
 192 }
 193
 194 extern struct inode_operations obdfs_inode_ops;
 195
 196 /* all filling in of inodes postponed until lookup */
 197 static void obdfs_read_inode(struct inode *inode)
 198 {
 199         int error;
 200         struct obdfs_sb_info *sbi = inode->i_sb->u.generic_sbp;
 201         ENTRY;
 202
 203         error = sbi->osi_ops->o_getattr(sbi->osi_conn_info.conn_id,
 204                                         inode->i_ino, inode);
 205         if (error) {
 206                 printk("obdfs_read_inode: ibd_getattr fails (%d)\n", error);
 207                 return;
 208         }
 209
 210         inode->i_op = &obdfs_inode_ops;
 211         return;
 212 }
 213
 214 static void obdfs_write_inode(struct inode *inode)
 215 {
 216         struct obdfs_sb_info *sbi;
 217         int error;
 218
 219         sbi = inode->i_sb->u.generic_sbp;
 220         error = sbi->osi_ops->o_setattr(sbi->osi_conn_info.conn_id,
 221                                         inode->i_ino, inode);
 222         if (error) {
 223                 printk("obdfs_write_inode: ibd_setattr fails (%d)\n", error);
 224                 return;
 225         }
 226
 227         return;
 228 }
 229
 230 static void obdfs_delete_inode(struct inode *inode)
 231 {
 232         struct obdfs_sb_info *sbi;
 233         int error;
 234         ENTRY;
 235
 236         sbi = inode->i_sb->u.generic_sbp;
 237         error = sbi->osi_ops->o_destroy(sbi->osi_conn_info.conn_id,
 238                                         inode->i_ino);
 239         if (error) {
 240                 printk("obdfs_delete_node: ibd_destroy fails (%d)\n", error);
 241                 return;
 242         }
 243
 244         EXIT;
 245 }
 246
 247 static int  obdfs_notify_change(struct dentry *de, struct iattr *iattr)
 248 {
 249         struct inode *inode = de->d_inode;
 250         struct iattr saved_copy;
 251         struct obdfs_sb_info * sbi;
 252         int error;
 253
 254         ENTRY;
 255         inode_to_iattr(inode, &saved_copy);
 256
 257         sbi = inode->i_sb->u.generic_sbp;
 258         inode_setattr(inode, iattr);
 259         error = sbi->osi_ops->o_setattr(sbi->osi_conn_info.conn_id,
 260                                         inode->i_ino, inode);
 261         if ( error ) {
 262                 inode_setattr(inode, &saved_copy);
 263                 printk("obdfs_notify_change: obd_setattr fails (%d)\n", error);
 264                 return error;
 265         }
 266         EXIT;
 267         return error;
 268 }
 269
 270
 271 static int obdfs_statfs(struct super_block *sb, struct statfs *buf,
 272                        int bufsize)
 273 {
 274         struct statfs tmp;
 275         struct obdfs_sb_info * sbi;
 276         int error;
 277
 278         ENTRY;
 279
 280         sbi = sb->u.generic_sbp;
 281         error = sbi->osi_ops->o_statfs(sbi->osi_conn_info.conn_id, &tmp);
 282         if ( error ) {
 283                 printk("obdfs_notify_change: obd_statfs fails (%d)\n", error);
 284                 return error;
 285         }
 286         copy_to_user(buf, &tmp, (bufsize<sizeof(tmp)) ? bufsize : sizeof(tmp));
 287
 288         EXIT;
 289
 290         return error;
 291 }
 292
 293 struct file_system_type obdfs_fs_type = {
 294    "obdfs", 0, obdfs_read_super, NULL
 295 };
 296
 297 int init_obdfs(void)
 298 {
 299         printk(KERN_INFO "OBDFS v0.1, braam@stelias.com\n");
 300
 301         obdfs_sysctl_init();
 302
 303         obd_sbi = &obdfs_super_info;
 304         obd_fso = &obdfs_file_ops;
 305
 306         return register_filesystem(&obdfs_fs_type);
 307 }
 308
 309
 310 #ifdef MODULE
 311 int init_module(void)
 312 {
 313         return init_obdfs();
 314 }
 315
 316 void cleanup_module(void)
 317 {
 318         ENTRY;
 319
 320         obdfs_sysctl_clean();
 321         unregister_filesystem(&obdfs_fs_type);
 322 }
 323 void obdfs_psdev_dec_use_count(void)
 324 {
 325         MOD_DEC_USE_COUNT;
 326 }
 327
 328 EXPORT_SYMBOL(obdfs_psdev_dec_use_count);
 329
 330 #endif