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
  39 #include "vxfs.h"
  40 #include "vxfs_inode.h"
  41 #include "vxfs_extern.h"
  42
  43
  44 struct kmem_cache               *vxfs_inode_cachep;
  45
  46
  47 #ifdef DIAGNOSTIC
  48 /*
  49  * Dump inode contents (partially).
  50  */
  51 void
  52 vxfs_dumpi(struct vxfs_inode_info *vip, ino_t ino)
  53 {
  54         printk(KERN_DEBUG "\n\n");
  55         if (ino)
  56                 printk(KERN_DEBUG "dumping vxfs inode %ld\n", ino);
  57         else
  58                 printk(KERN_DEBUG "dumping unknown vxfs inode\n");
  59
  60         printk(KERN_DEBUG "---------------------------\n");
  61         printk(KERN_DEBUG "mode is %x\n", vip->vii_mode);
  62         printk(KERN_DEBUG "nlink:%u, uid:%u, gid:%u\n",
  63                         vip->vii_nlink, vip->vii_uid, vip->vii_gid);
  64         printk(KERN_DEBUG "size:%Lx, blocks:%u\n",
  65                         vip->vii_size, vip->vii_blocks);
  66         printk(KERN_DEBUG "orgtype:%u\n", vip->vii_orgtype);
  67 }
  68 #endif
  69
  70
  71 /**
  72  * vxfs_blkiget - find inode based on extent #
  73  * @sbp:        superblock of the filesystem we search in
  74  * @extent:     number of the extent to search
  75  * @ino:        inode number to search
  76  *
  77  * Description:
  78  *  vxfs_blkiget searches inode @ino in the filesystem described by
  79  *  @sbp in the extent @extent.
  80  *  Returns the matching VxFS inode on success, else a NULL pointer.
  81  *
  82  * NOTE:
  83  *  While __vxfs_iget uses the pagecache vxfs_blkiget uses the
  84  *  buffercache.  This function should not be used outside the
  85  *  read_super() method, otherwise the data may be incoherent.
  86  */
  87 struct vxfs_inode_info *
  88 vxfs_blkiget(struct super_block *sbp, u_long extent, ino_t ino)
  89 {
  90         struct buffer_head              *bp;
  91         u_long                          block, offset;
  92
  93         block = extent + ((ino * VXFS_ISIZE) / sbp->s_blocksize);
  94         offset = ((ino % (sbp->s_blocksize / VXFS_ISIZE)) * VXFS_ISIZE);
  95         bp = sb_bread(sbp, block);
  96
  97         if (bp && buffer_mapped(bp)) {
  98                 struct vxfs_inode_info  *vip;
  99                 struct vxfs_dinode      *dip;
 100
 101                 if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
 102                         goto fail;
 103                 dip = (struct vxfs_dinode *)(bp->b_data + offset);
 104                 memcpy(vip, dip, sizeof(*vip));
 105 #ifdef DIAGNOSTIC
 106                 vxfs_dumpi(vip, ino);
 107 #endif
 108                 brelse(bp);
 109                 return (vip);
 110         }
 111
 112 fail:
 113         printk(KERN_WARNING "vxfs: unable to read block %ld\n", block);
 114         brelse(bp);
 115         return NULL;
 116 }
 117
 118 /**
 119  * __vxfs_iget - generic find inode facility
 120  * @sbp:                VFS superblock
 121  * @ino:                inode number
 122  * @ilistp:             inode list
 123  *
 124  * Description:
 125  *  Search the for inode number @ino in the filesystem
 126  *  described by @sbp.  Use the specified inode table (@ilistp).
 127  *  Returns the matching VxFS inode on success, else an error code.
 128  */
 129 static struct vxfs_inode_info *
 130 __vxfs_iget(ino_t ino, struct inode *ilistp)
 131 {
 132         struct page                     *pp;
 133         u_long                          offset;
 134
 135         offset = (ino % (PAGE_SIZE / VXFS_ISIZE)) * VXFS_ISIZE;
 136         pp = vxfs_get_page(ilistp->i_mapping, ino * VXFS_ISIZE / PAGE_SIZE);
 137
 138         if (!IS_ERR(pp)) {
 139                 struct vxfs_inode_info  *vip;
 140                 struct vxfs_dinode      *dip;
 141                 caddr_t                 kaddr = (char *)page_address(pp);
 142
 143                 if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
 144                         goto fail;
 145                 dip = (struct vxfs_dinode *)(kaddr + offset);
 146                 memcpy(vip, dip, sizeof(*vip));
 147 #ifdef DIAGNOSTIC
 148                 vxfs_dumpi(vip, ino);
 149 #endif
 150                 vxfs_put_page(pp);
 151                 return (vip);
 152         }
 153
 154         printk(KERN_WARNING "vxfs: error on page %p\n", pp);
 155         return ERR_CAST(pp);
 156
 157 fail:
 158         printk(KERN_WARNING "vxfs: unable to read inode %ld\n", (unsigned long)ino);
 159         vxfs_put_page(pp);
 160         return ERR_PTR(-ENOMEM);
 161 }
 162
 163 /**
 164  * vxfs_stiget - find inode using the structural inode list
 165  * @sbp:        VFS superblock
 166  * @ino:        inode #
 167  *
 168  * Description:
 169  *  Find inode @ino in the filesystem described by @sbp using
 170  *  the structural inode list.
 171  *  Returns the matching VxFS inode on success, else a NULL pointer.
 172  */
 173 struct vxfs_inode_info *
 174 vxfs_stiget(struct super_block *sbp, ino_t ino)
 175 {
 176         struct vxfs_inode_info *vip;
 177
 178         vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
 179         return IS_ERR(vip) ? NULL : vip;
 180 }
 181
 182 /**
 183  * vxfs_transmod - mode for a VxFS inode
 184  * @vip:        VxFS inode
 185  *
 186  * Description:
 187  *  vxfs_transmod returns a Linux mode_t for a given
 188  *  VxFS inode structure.
 189  */
 190 static __inline__ umode_t
 191 vxfs_transmod(struct vxfs_inode_info *vip)
 192 {
 193         umode_t                 ret = vip->vii_mode & ~VXFS_TYPE_MASK;
 194
 195         if (VXFS_ISFIFO(vip))
 196                 ret |= S_IFIFO;
 197         if (VXFS_ISCHR(vip))
 198                 ret |= S_IFCHR;
 199         if (VXFS_ISDIR(vip))
 200                 ret |= S_IFDIR;
 201         if (VXFS_ISBLK(vip))
 202                 ret |= S_IFBLK;
 203         if (VXFS_ISLNK(vip))
 204                 ret |= S_IFLNK;
 205         if (VXFS_ISREG(vip))
 206                 ret |= S_IFREG;
 207         if (VXFS_ISSOC(vip))
 208                 ret |= S_IFSOCK;
 209
 210         return (ret);
 211 }
 212
 213 /**
 214  * vxfs_iinit- helper to fill inode fields
 215  * @ip:         VFS inode
 216  * @vip:        VxFS inode
 217  *
 218  * Description:
 219  *  vxfs_instino is a helper function to fill in all relevant
 220  *  fields in @ip from @vip.
 221  */
 222 static void
 223 vxfs_iinit(struct inode *ip, struct vxfs_inode_info *vip)
 224 {
 225
 226         ip->i_mode = vxfs_transmod(vip);
 227         ip->i_uid = (uid_t)vip->vii_uid;
 228         ip->i_gid = (gid_t)vip->vii_gid;
 229
 230         set_nlink(ip, vip->vii_nlink);
 231         ip->i_size = vip->vii_size;
 232
 233         ip->i_atime.tv_sec = vip->vii_atime;
 234         ip->i_ctime.tv_sec = vip->vii_ctime;
 235         ip->i_mtime.tv_sec = vip->vii_mtime;
 236         ip->i_atime.tv_nsec = 0;
 237         ip->i_ctime.tv_nsec = 0;
 238         ip->i_mtime.tv_nsec = 0;
 239
 240         ip->i_blocks = vip->vii_blocks;
 241         ip->i_generation = vip->vii_gen;
 242
 243         ip->i_private = vip;
 244
 245 }
 246
 247 /**
 248  * vxfs_get_fake_inode - get fake inode structure
 249  * @sbp:                filesystem superblock
 250  * @vip:                fspriv inode
 251  *
 252  * Description:
 253  *  vxfs_fake_inode gets a fake inode (not in the inode hash) for a
 254  *  superblock, vxfs_inode pair.
 255  *  Returns the filled VFS inode.
 256  */
 257 struct inode *
 258 vxfs_get_fake_inode(struct super_block *sbp, struct vxfs_inode_info *vip)
 259 {
 260         struct inode                    *ip = NULL;
 261
 262         if ((ip = new_inode(sbp))) {
 263                 ip->i_ino = get_next_ino();
 264                 vxfs_iinit(ip, vip);
 265                 ip->i_mapping->a_ops = &vxfs_aops;
 266         }
 267         return (ip);
 268 }
 269
 270 /**
 271  * vxfs_put_fake_inode - free faked inode
 272  * *ip:                 VFS inode
 273  *
 274  * Description:
 275  *  vxfs_put_fake_inode frees all data associated with @ip.
 276  */
 277 void
 278 vxfs_put_fake_inode(struct inode *ip)
 279 {
 280         iput(ip);
 281 }
 282
 283 /**
 284  * vxfs_iget - get an inode
 285  * @sbp:        the superblock to get the inode for
 286  * @ino:        the number of the inode to get
 287  *
 288  * Description:
 289  *  vxfs_read_inode creates an inode, reads the disk inode for @ino and fills
 290  *  in all relevant fields in the new inode.
 291  */
 292 struct inode *
 293 vxfs_iget(struct super_block *sbp, ino_t ino)
 294 {
 295         struct vxfs_inode_info          *vip;
 296         const struct address_space_operations   *aops;
 297         struct inode *ip;
 298
 299         ip = iget_locked(sbp, ino);
 300         if (!ip)
 301                 return ERR_PTR(-ENOMEM);
 302         if (!(ip->i_state & I_NEW))
 303                 return ip;
 304
 305         vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist);
 306         if (IS_ERR(vip)) {
 307                 iget_failed(ip);
 308                 return ERR_CAST(vip);
 309         }
 310
 311         vxfs_iinit(ip, vip);
 312
 313         if (VXFS_ISIMMED(vip))
 314                 aops = &vxfs_immed_aops;
 315         else
 316                 aops = &vxfs_aops;
 317
 318         if (S_ISREG(ip->i_mode)) {
 319                 ip->i_fop = &generic_ro_fops;
 320                 ip->i_mapping->a_ops = aops;
 321         } else if (S_ISDIR(ip->i_mode)) {
 322                 ip->i_op = &vxfs_dir_inode_ops;
 323                 ip->i_fop = &vxfs_dir_operations;
 324                 ip->i_mapping->a_ops = aops;
 325         } else if (S_ISLNK(ip->i_mode)) {
 326                 if (!VXFS_ISIMMED(vip)) {
 327                         ip->i_op = &page_symlink_inode_operations;
 328                         ip->i_mapping->a_ops = &vxfs_aops;
 329                 } else {
 330                         ip->i_op = &vxfs_immed_symlink_iops;
 331                         vip->vii_immed.vi_immed[ip->i_size] = '\0';
 332                 }
 333         } else
 334                 init_special_inode(ip, ip->i_mode, old_decode_dev(vip->vii_rdev));
 335
 336         unlock_new_inode(ip);
 337         return ip;
 338 }
 339
 340 static void vxfs_i_callback(struct rcu_head *head)
 341 {
 342         struct inode *inode = container_of(head, struct inode, i_rcu);
 343         kmem_cache_free(vxfs_inode_cachep, inode->i_private);
 344 }
 345
 346 /**
 347  * vxfs_evict_inode - remove inode from main memory
 348  * @ip:         inode to discard.
 349  *
 350  * Description:
 351  *  vxfs_evict_inode() is called on the final iput and frees the private
 352  *  inode area.
 353  */
 354 void
 355 vxfs_evict_inode(struct inode *ip)
 356 {
 357         truncate_inode_pages(&ip->i_data, 0);
 358         end_writeback(ip);
 359         call_rcu(&ip->i_rcu, vxfs_i_callback);
 360 }