fs/jfs/inode.c

   1 /*
   2  *   Copyright (C) International Business Machines Corp., 2000-2004
   3  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
   4  *
   5  *   This program is free software;  you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation; either version 2 of the License, or
   8  *   (at your option) any later version.
   9  *
  10  *   This program is distributed in the hope that it will be useful,
  11  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  13  *   the GNU General Public License for more details.
  14  *
  15  *   You should have received a copy of the GNU General Public License
  16  *   along with this program;  if not, write to the Free Software
  17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  */
  19
  20 #include <linux/fs.h>
  21 #include <linux/mpage.h>
  22 #include <linux/buffer_head.h>
  23 #include <linux/pagemap.h>
  24 #include <linux/quotaops.h>
  25 #include "jfs_incore.h"
  26 #include "jfs_inode.h"
  27 #include "jfs_filsys.h"
  28 #include "jfs_imap.h"
  29 #include "jfs_extent.h"
  30 #include "jfs_unicode.h"
  31 #include "jfs_debug.h"
  32
  33
  34 struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
  35 {
  36         struct inode *inode;
  37         int ret;
  38
  39         inode = iget_locked(sb, ino);
  40         if (!inode)
  41                 return ERR_PTR(-ENOMEM);
  42         if (!(inode->i_state & I_NEW))
  43                 return inode;
  44
  45         ret = diRead(inode);
  46         if (ret < 0) {
  47                 iget_failed(inode);
  48                 return ERR_PTR(ret);
  49         }
  50
  51         if (S_ISREG(inode->i_mode)) {
  52                 inode->i_op = &jfs_file_inode_operations;
  53                 inode->i_fop = &jfs_file_operations;
  54                 inode->i_mapping->a_ops = &jfs_aops;
  55         } else if (S_ISDIR(inode->i_mode)) {
  56                 inode->i_op = &jfs_dir_inode_operations;
  57                 inode->i_fop = &jfs_dir_operations;
  58         } else if (S_ISLNK(inode->i_mode)) {
  59                 if (inode->i_size >= IDATASIZE) {
  60                         inode->i_op = &page_symlink_inode_operations;
  61                         inode->i_mapping->a_ops = &jfs_aops;
  62                 } else
  63                         inode->i_op = &jfs_symlink_inode_operations;
  64         } else {
  65                 inode->i_op = &jfs_file_inode_operations;
  66                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
  67         }
  68         unlock_new_inode(inode);
  69         return inode;
  70 }
  71
  72 /*
  73  * Workhorse of both fsync & write_inode
  74  */
  75 int jfs_commit_inode(struct inode *inode, int wait)
  76 {
  77         int rc = 0;
  78         tid_t tid;
  79         static int noisy = 5;
  80
  81         jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
  82
  83         /*
  84          * Don't commit if inode has been committed since last being
  85          * marked dirty, or if it has been deleted.
  86          */
  87         if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
  88                 return 0;
  89
  90         if (isReadOnly(inode)) {
  91                 /* kernel allows writes to devices on read-only
  92                  * partitions and may think inode is dirty
  93                  */
  94                 if (!special_file(inode->i_mode) && noisy) {
  95                         jfs_err("jfs_commit_inode(0x%p) called on "
  96                                    "read-only volume", inode);
  97                         jfs_err("Is remount racy?");
  98                         noisy--;
  99                 }
 100                 return 0;
 101         }
 102
 103         tid = txBegin(inode->i_sb, COMMIT_INODE);
 104         mutex_lock(&JFS_IP(inode)->commit_mutex);
 105
 106         /*
 107          * Retest inode state after taking commit_mutex
 108          */
 109         if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
 110                 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
 111
 112         txEnd(tid);
 113         mutex_unlock(&JFS_IP(inode)->commit_mutex);
 114         return rc;
 115 }
 116
 117 int jfs_write_inode(struct inode *inode, int wait)
 118 {
 119         if (test_cflag(COMMIT_Nolink, inode))
 120                 return 0;
 121         /*
 122          * If COMMIT_DIRTY is not set, the inode isn't really dirty.
 123          * It has been committed since the last change, but was still
 124          * on the dirty inode list.
 125          */
 126          if (!test_cflag(COMMIT_Dirty, inode)) {
 127                 /* Make sure committed changes hit the disk */
 128                 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
 129                 return 0;
 130          }
 131
 132         if (jfs_commit_inode(inode, wait)) {
 133                 jfs_err("jfs_write_inode: jfs_commit_inode failed!");
 134                 return -EIO;
 135         } else
 136                 return 0;
 137 }
 138
 139 void jfs_delete_inode(struct inode *inode)
 140 {
 141         jfs_info("In jfs_delete_inode, inode = 0x%p", inode);
 142
 143         if (!is_bad_inode(inode) &&
 144             (JFS_IP(inode)->fileset == FILESYSTEM_I)) {
 145                 truncate_inode_pages(&inode->i_data, 0);
 146
 147                 if (test_cflag(COMMIT_Freewmap, inode))
 148                         jfs_free_zero_link(inode);
 149
 150                 diFree(inode);
 151
 152                 /*
 153                  * Free the inode from the quota allocation.
 154                  */
 155                 DQUOT_INIT(inode);
 156                 DQUOT_FREE_INODE(inode);
 157                 DQUOT_DROP(inode);
 158         }
 159
 160         clear_inode(inode);
 161 }
 162
 163 void jfs_dirty_inode(struct inode *inode)
 164 {
 165         static int noisy = 5;
 166
 167         if (isReadOnly(inode)) {
 168                 if (!special_file(inode->i_mode) && noisy) {
 169                         /* kernel allows writes to devices on read-only
 170                          * partitions and may try to mark inode dirty
 171                          */
 172                         jfs_err("jfs_dirty_inode called on read-only volume");
 173                         jfs_err("Is remount racy?");
 174                         noisy--;
 175                 }
 176                 return;
 177         }
 178
 179         set_cflag(COMMIT_Dirty, inode);
 180 }
 181
 182 int jfs_get_block(struct inode *ip, sector_t lblock,
 183                   struct buffer_head *bh_result, int create)
 184 {
 185         s64 lblock64 = lblock;
 186         int rc = 0;
 187         xad_t xad;
 188         s64 xaddr;
 189         int xflag;
 190         s32 xlen = bh_result->b_size >> ip->i_blkbits;
 191
 192         /*
 193          * Take appropriate lock on inode
 194          */
 195         if (create)
 196                 IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 197         else
 198                 IREAD_LOCK(ip, RDWRLOCK_NORMAL);
 199
 200         if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
 201             (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
 202             xaddr) {
 203                 if (xflag & XAD_NOTRECORDED) {
 204                         if (!create)
 205                                 /*
 206                                  * Allocated but not recorded, read treats
 207                                  * this as a hole
 208                                  */
 209                                 goto unlock;
 210 #ifdef _JFS_4K
 211                         XADoffset(&xad, lblock64);
 212                         XADlength(&xad, xlen);
 213                         XADaddress(&xad, xaddr);
 214 #else                           /* _JFS_4K */
 215                         /*
 216                          * As long as block size = 4K, this isn't a problem.
 217                          * We should mark the whole page not ABNR, but how
 218                          * will we know to mark the other blocks BH_New?
 219                          */
 220                         BUG();
 221 #endif                          /* _JFS_4K */
 222                         rc = extRecord(ip, &xad);
 223                         if (rc)
 224                                 goto unlock;
 225                         set_buffer_new(bh_result);
 226                 }
 227
 228                 map_bh(bh_result, ip->i_sb, xaddr);
 229                 bh_result->b_size = xlen << ip->i_blkbits;
 230                 goto unlock;
 231         }
 232         if (!create)
 233                 goto unlock;
 234
 235         /*
 236          * Allocate a new block
 237          */
 238 #ifdef _JFS_4K
 239         if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
 240                 goto unlock;
 241         rc = extAlloc(ip, xlen, lblock64, &xad, false);
 242         if (rc)
 243                 goto unlock;
 244
 245         set_buffer_new(bh_result);
 246         map_bh(bh_result, ip->i_sb, addressXAD(&xad));
 247         bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
 248
 249 #else                           /* _JFS_4K */
 250         /*
 251          * We need to do whatever it takes to keep all but the last buffers
 252          * in 4K pages - see jfs_write.c
 253          */
 254         BUG();
 255 #endif                          /* _JFS_4K */
 256
 257       unlock:
 258         /*
 259          * Release lock on inode
 260          */
 261         if (create)
 262                 IWRITE_UNLOCK(ip);
 263         else
 264                 IREAD_UNLOCK(ip);
 265         return rc;
 266 }
 267
 268 static int jfs_writepage(struct page *page, struct writeback_control *wbc)
 269 {
 270         return block_write_full_page(page, jfs_get_block, wbc);
 271 }
 272
 273 static int jfs_writepages(struct address_space *mapping,
 274                         struct writeback_control *wbc)
 275 {
 276         return mpage_writepages(mapping, wbc, jfs_get_block);
 277 }
 278
 279 static int jfs_readpage(struct file *file, struct page *page)
 280 {
 281         return mpage_readpage(page, jfs_get_block);
 282 }
 283
 284 static int jfs_readpages(struct file *file, struct address_space *mapping,
 285                 struct list_head *pages, unsigned nr_pages)
 286 {
 287         return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
 288 }
 289
 290 static int jfs_write_begin(struct file *file, struct address_space *mapping,
 291                                 loff_t pos, unsigned len, unsigned flags,
 292                                 struct page **pagep, void **fsdata)
 293 {
 294         return nobh_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
 295                                 jfs_get_block);
 296 }
 297
 298 static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
 299 {
 300         return generic_block_bmap(mapping, block, jfs_get_block);
 301 }
 302
 303 static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 304         const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 305 {
 306         struct file *file = iocb->ki_filp;
 307         struct inode *inode = file->f_mapping->host;
 308
 309         return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 310                                 offset, nr_segs, jfs_get_block, NULL);
 311 }
 312
 313 const struct address_space_operations jfs_aops = {
 314         .readpage       = jfs_readpage,
 315         .readpages      = jfs_readpages,
 316         .writepage      = jfs_writepage,
 317         .writepages     = jfs_writepages,
 318         .sync_page      = block_sync_page,
 319         .write_begin    = jfs_write_begin,
 320         .write_end      = nobh_write_end,
 321         .bmap           = jfs_bmap,
 322         .direct_IO      = jfs_direct_IO,
 323 };
 324
 325 /*
 326  * Guts of jfs_truncate.  Called with locks already held.  Can be called
 327  * with directory for truncating directory index table.
 328  */
 329 void jfs_truncate_nolock(struct inode *ip, loff_t length)
 330 {
 331         loff_t newsize;
 332         tid_t tid;
 333
 334         ASSERT(length >= 0);
 335
 336         if (test_cflag(COMMIT_Nolink, ip)) {
 337                 xtTruncate(0, ip, length, COMMIT_WMAP);
 338                 return;
 339         }
 340
 341         do {
 342                 tid = txBegin(ip->i_sb, 0);
 343
 344                 /*
 345                  * The commit_mutex cannot be taken before txBegin.
 346                  * txBegin may block and there is a chance the inode
 347                  * could be marked dirty and need to be committed
 348                  * before txBegin unblocks
 349                  */
 350                 mutex_lock(&JFS_IP(ip)->commit_mutex);
 351
 352                 newsize = xtTruncate(tid, ip, length,
 353                                      COMMIT_TRUNCATE | COMMIT_PWMAP);
 354                 if (newsize < 0) {
 355                         txEnd(tid);
 356                         mutex_unlock(&JFS_IP(ip)->commit_mutex);
 357                         break;
 358                 }
 359
 360                 ip->i_mtime = ip->i_ctime = CURRENT_TIME;
 361                 mark_inode_dirty(ip);
 362
 363                 txCommit(tid, 1, &ip, 0);
 364                 txEnd(tid);
 365                 mutex_unlock(&JFS_IP(ip)->commit_mutex);
 366         } while (newsize > length);     /* Truncate isn't always atomic */
 367 }
 368
 369 void jfs_truncate(struct inode *ip)
 370 {
 371         jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
 372
 373         nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
 374
 375         IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 376         jfs_truncate_nolock(ip, ip->i_size);
 377         IWRITE_UNLOCK(ip);
 378 }