fs/freevxfs/vxfs_inode.c

   1 /*
   2  * Copyright (c) 2000-2001 Christoph Hellwig.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions, and the following disclaimer,
  10  *    without modification.
  11  * 2. The name of the author may not be used to endorse or promote products
  12  *    derived from this software without specific prior written permission.
  13  *
  14  * Alternatively, this software may be distributed under the terms of the
  15  * GNU General Public License ("GPL").
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * Veritas filesystem driver - inode routines.
  32  */
  33 #include <linux/fs.h>
  34 #include <linux/buffer_head.h>
  35 #include <linux/pagemap.h>
  36 #include <linux/kernel.h>
  37 #include <linux/slab.h>
  38 #include <linux/namei.h>
  39
  40 #include "vxfs.h"
  41 #include "vxfs_inode.h"
  42 #include "vxfs_extern.h"
  43
  44
  45 struct kmem_cache               *vxfs_inode_cachep;
  46
  47
  48 #ifdef DIAGNOSTIC
  49 /*
  50  * Dump inode contents (partially).
  51  */
  52 void
  53 vxfs_dumpi(struct vxfs_inode_info *vip, ino_t ino)
  54 {
  55         printk(KERN_DEBUG "\n\n");
  56         if (ino)
  57                 printk(KERN_DEBUG "dumping vxfs inode %ld\n", ino);
  58         else
  59                 printk(KERN_DEBUG "dumping unknown vxfs inode\n");
  60
  61         printk(KERN_DEBUG "---------------------------\n");
  62         printk(KERN_DEBUG "mode is %x\n", vip->vii_mode);
  63         printk(KERN_DEBUG "nlink:%u, uid:%u, gid:%u\n",
  64                         vip->vii_nlink, vip->vii_uid, vip->vii_gid);
  65         printk(KERN_DEBUG "size:%Lx, blocks:%u\n",
  66                         vip->vii_size, vip->vii_blocks);
  67         printk(KERN_DEBUG "orgtype:%u\n", vip->vii_orgtype);
  68 }
  69 #endif
  70
  71
  72 /**
  73  * vxfs_blkiget - find inode based on extent #
  74  * @sbp:        superblock of the filesystem we search in
  75  * @extent:     number of the extent to search
  76  * @ino:        inode number to search
  77  *
  78  * Description:
  79  *  vxfs_blkiget searches inode @ino in the filesystem described by
  80  *  @sbp in the extent @extent.
  81  *  Returns the matching VxFS inode on success, else a NULL pointer.
  82  *
  83  * NOTE:
  84  *  While __vxfs_iget uses the pagecache vxfs_blkiget uses the
  85  *  buffercache.  This function should not be used outside the
  86  *  read_super() method, otherwise the data may be incoherent.
  87  */
  88 struct vxfs_inode_info *
  89 vxfs_blkiget(struct super_block *sbp, u_long extent, ino_t ino)
  90 {
  91         struct buffer_head              *bp;
  92         u_long                          block, offset;
  93
  94         block = extent + ((ino * VXFS_ISIZE) / sbp->s_blocksize);
  95         offset = ((ino % (sbp->s_blocksize / VXFS_ISIZE)) * VXFS_ISIZE);
  96         bp = sb_bread(sbp, block);
  97
  98         if (bp && buffer_mapped(bp)) {
  99                 struct vxfs_inode_info  *vip;
 100                 struct vxfs_dinode      *dip;
 101
 102                 if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
 103                         goto fail;
 104                 dip = (struct vxfs_dinode *)(bp->b_data + offset);
 105                 memcpy(vip, dip, sizeof(*vip));
 106 #ifdef DIAGNOSTIC
 107                 vxfs_dumpi(vip, ino);
 108 #endif
 109                 brelse(bp);
 110                 return (vip);
 111         }
 112
 113 fail:
 114         printk(KERN_WARNING "vxfs: unable to read block %ld\n", block);
 115         brelse(bp);
 116         return NULL;
 117 }
 118
 119 /**
 120  * __vxfs_iget - generic find inode facility
 121  * @sbp:                VFS superblock
 122  * @ino:                inode number
 123  * @ilistp:             inode list
 124  *
 125  * Description:
 126  *  Search the for inode number @ino in the filesystem
 127  *  described by @sbp.  Use the specified inode table (@ilistp).
 128  *  Returns the matching VxFS inode on success, else an error code.
 129  */
 130 static struct vxfs_inode_info *
 131 __vxfs_iget(ino_t ino, struct inode *ilistp)
 132 {
 133         struct page                     *pp;
 134         u_long                          offset;
 135
 136         offset = (ino % (PAGE_SIZE / VXFS_ISIZE)) * VXFS_ISIZE;
 137         pp = vxfs_get_page(ilistp->i_mapping, ino * VXFS_ISIZE / PAGE_SIZE);
 138
 139         if (!IS_ERR(pp)) {
 140                 struct vxfs_inode_info  *vip;
 141                 struct vxfs_dinode      *dip;
 142                 caddr_t                 kaddr = (char *)page_address(pp);
 143
 144                 if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
 145                         goto fail;
 146                 dip = (struct vxfs_dinode *)(kaddr + offset);
 147                 memcpy(vip, dip, sizeof(*vip));
 148 #ifdef DIAGNOSTIC
 149                 vxfs_dumpi(vip, ino);
 150 #endif
 151                 vxfs_put_page(pp);
 152                 return (vip);
 153         }
 154
 155         printk(KERN_WARNING "vxfs: error on page %p\n", pp);
 156         return ERR_CAST(pp);
 157
 158 fail:
 159         printk(KERN_WARNING "vxfs: unable to read inode %ld\n", (unsigned long)ino);
 160         vxfs_put_page(pp);
 161         return ERR_PTR(-ENOMEM);
 162 }
 163
 164 /**
 165  * vxfs_stiget - find inode using the structural inode list
 166  * @sbp:        VFS superblock
 167  * @ino:        inode #
 168  *
 169  * Description:
 170  *  Find inode @ino in the filesystem described by @sbp using
 171  *  the structural inode list.
 172  *  Returns the matching VxFS inode on success, else a NULL pointer.
 173  */
 174 struct vxfs_inode_info *
 175 vxfs_stiget(struct super_block *sbp, ino_t ino)
 176 {
 177         struct vxfs_inode_info *vip;
 178
 179         vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
 180         return IS_ERR(vip) ? NULL : vip;
 181 }
 182
 183 /**
 184  * vxfs_transmod - mode for a VxFS inode
 185  * @vip:        VxFS inode
 186  *
 187  * Description:
 188  *  vxfs_transmod returns a Linux mode_t for a given
 189  *  VxFS inode structure.
 190  */
 191 static __inline__ umode_t
 192 vxfs_transmod(struct vxfs_inode_info *vip)
 193 {
 194         umode_t                 ret = vip->vii_mode & ~VXFS_TYPE_MASK;
 195
 196         if (VXFS_ISFIFO(vip))
 197                 ret |= S_IFIFO;
 198         if (VXFS_ISCHR(vip))
 199                 ret |= S_IFCHR;
 200         if (VXFS_ISDIR(vip))
 201                 ret |= S_IFDIR;
 202         if (VXFS_ISBLK(vip))
 203                 ret |= S_IFBLK;
 204         if (VXFS_ISLNK(vip))
 205                 ret |= S_IFLNK;
 206         if (VXFS_ISREG(vip))
 207                 ret |= S_IFREG;
 208         if (VXFS_ISSOC(vip))
 209                 ret |= S_IFSOCK;
 210
 211         return (ret);
 212 }
 213
 214 /**
 215  * vxfs_iinit- helper to fill inode fields
 216  * @ip:         VFS inode
 217  * @vip:        VxFS inode
 218  *
 219  * Description:
 220  *  vxfs_instino is a helper function to fill in all relevant
 221  *  fields in @ip from @vip.
 222  */
 223 static void
 224 vxfs_iinit(struct inode *ip, struct vxfs_inode_info *vip)
 225 {
 226
 227         ip->i_mode = vxfs_transmod(vip);
 228         i_uid_write(ip, (uid_t)vip->vii_uid);
 229         i_gid_write(ip, (gid_t)vip->vii_gid);
 230
 231         set_nlink(ip, vip->vii_nlink);
 232         ip->i_size = vip->vii_size;
 233
 234         ip->i_atime.tv_sec = vip->vii_atime;
 235         ip->i_ctime.tv_sec = vip->vii_ctime;
 236         ip->i_mtime.tv_sec = vip->vii_mtime;
 237         ip->i_atime.tv_nsec = 0;
 238         ip->i_ctime.tv_nsec = 0;
 239         ip->i_mtime.tv_nsec = 0;
 240
 241         ip->i_blocks = vip->vii_blocks;
 242         ip->i_generation = vip->vii_gen;
 243
 244         ip->i_private = vip;
 245
 246 }
 247
 248 /**
 249  * vxfs_get_fake_inode - get fake inode structure
 250  * @sbp:                filesystem superblock
 251  * @vip:                fspriv inode
 252  *
 253  * Description:
 254  *  vxfs_fake_inode gets a fake inode (not in the inode hash) for a
 255  *  superblock, vxfs_inode pair.
 256  *  Returns the filled VFS inode.
 257  */
 258 struct inode *
 259 vxfs_get_fake_inode(struct super_block *sbp, struct vxfs_inode_info *vip)
 260 {
 261         struct inode                    *ip = NULL;
 262
 263         if ((ip = new_inode(sbp))) {
 264                 ip->i_ino = get_next_ino();
 265                 vxfs_iinit(ip, vip);
 266                 ip->i_mapping->a_ops = &vxfs_aops;
 267         }
 268         return (ip);
 269 }
 270
 271 /**
 272  * vxfs_put_fake_inode - free faked inode
 273  * *ip:                 VFS inode
 274  *
 275  * Description:
 276  *  vxfs_put_fake_inode frees all data associated with @ip.
 277  */
 278 void
 279 vxfs_put_fake_inode(struct inode *ip)
 280 {
 281         iput(ip);
 282 }
 283
 284 /**
 285  * vxfs_iget - get an inode
 286  * @sbp:        the superblock to get the inode for
 287  * @ino:        the number of the inode to get
 288  *
 289  * Description:
 290  *  vxfs_read_inode creates an inode, reads the disk inode for @ino and fills
 291  *  in all relevant fields in the new inode.
 292  */
 293 struct inode *
 294 vxfs_iget(struct super_block *sbp, ino_t ino)
 295 {
 296         struct vxfs_inode_info          *vip;
 297         const struct address_space_operations   *aops;
 298         struct inode *ip;
 299
 300         ip = iget_locked(sbp, ino);
 301         if (!ip)
 302                 return ERR_PTR(-ENOMEM);
 303         if (!(ip->i_state & I_NEW))
 304                 return ip;
 305
 306         vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist);
 307         if (IS_ERR(vip)) {
 308                 iget_failed(ip);
 309                 return ERR_CAST(vip);
 310         }
 311
 312         vxfs_iinit(ip, vip);
 313
 314         if (VXFS_ISIMMED(vip))
 315                 aops = &vxfs_immed_aops;
 316         else
 317                 aops = &vxfs_aops;
 318
 319         if (S_ISREG(ip->i_mode)) {
 320                 ip->i_fop = &generic_ro_fops;
 321                 ip->i_mapping->a_ops = aops;
 322         } else if (S_ISDIR(ip->i_mode)) {
 323                 ip->i_op = &vxfs_dir_inode_ops;
 324                 ip->i_fop = &vxfs_dir_operations;
 325                 ip->i_mapping->a_ops = aops;
 326         } else if (S_ISLNK(ip->i_mode)) {
 327                 if (!VXFS_ISIMMED(vip)) {
 328                         ip->i_op = &page_symlink_inode_operations;
 329                         inode_nohighmem(ip);
 330                         ip->i_mapping->a_ops = &vxfs_aops;
 331                 } else {
 332                         ip->i_op = &simple_symlink_inode_operations;
 333                         ip->i_link = vip->vii_immed.vi_immed;
 334                         nd_terminate_link(ip->i_link, ip->i_size,
 335                                           sizeof(vip->vii_immed.vi_immed) - 1);
 336                 }
 337         } else
 338                 init_special_inode(ip, ip->i_mode, old_decode_dev(vip->vii_rdev));
 339
 340         unlock_new_inode(ip);
 341         return ip;
 342 }
 343
 344 static void vxfs_i_callback(struct rcu_head *head)
 345 {
 346         struct inode *inode = container_of(head, struct inode, i_rcu);
 347         kmem_cache_free(vxfs_inode_cachep, inode->i_private);
 348 }
 349
 350 /**
 351  * vxfs_evict_inode - remove inode from main memory
 352  * @ip:         inode to discard.
 353  *
 354  * Description:
 355  *  vxfs_evict_inode() is called on the final iput and frees the private
 356  *  inode area.
 357  */
 358 void
 359 vxfs_evict_inode(struct inode *ip)
 360 {
 361         truncate_inode_pages_final(&ip->i_data);
 362         clear_inode(ip);
 363         call_rcu(&ip->i_rcu, vxfs_i_callback);
 364 }