fs/jfs/inode.c

   1 /*
   2  *   Copyright (c) International Business Machines Corp., 2000-2002
   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/locks.h>
  22 #include "jfs_incore.h"
  23 #include "jfs_filsys.h"
  24 #include "jfs_dmap.h"
  25 #include "jfs_imap.h"
  26 #include "jfs_extent.h"
  27 #include "jfs_unicode.h"
  28 #include "jfs_debug.h"
  29
  30
  31 extern struct inode_operations jfs_dir_inode_operations;
  32 extern struct inode_operations jfs_file_inode_operations;
  33 extern struct inode_operations jfs_symlink_inode_operations;
  34 extern struct file_operations jfs_dir_operations;
  35 extern struct file_operations jfs_file_operations;
  36 struct address_space_operations jfs_aops;
  37 extern int freeZeroLink(struct inode *);
  38
  39 void jfs_clear_inode(struct inode *inode)
  40 {
  41         struct jfs_inode_info *ji = JFS_IP(inode);
  42
  43         if (is_bad_inode(inode))
  44                 /*
  45                  * We free the fs-dependent structure before making the
  46                  * inode bad
  47                  */
  48                 return;
  49
  50         jfs_info("jfs_clear_inode called ip = 0x%p", inode);
  51
  52         spin_lock_irq(&ji->ag_lock);
  53         if (ji->active_ag != -1) {
  54                 struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
  55                 atomic_dec(&bmap->db_active[ji->active_ag]);
  56                 ji->active_ag = -1;
  57         }
  58         spin_unlock_irq(&ji->ag_lock);
  59
  60         ASSERT(list_empty(&ji->anon_inode_list));
  61
  62         if (ji->atlhead) {
  63                 jfs_err("jfs_clear_inode: inode %p has anonymous tlocks",
  64                         inode);
  65                 jfs_err("i_state = 0x%lx, cflag = 0x%lx", inode->i_state,
  66                         ji->cflag);
  67         }
  68
  69         free_jfs_inode(inode);
  70 }
  71
  72 void jfs_read_inode(struct inode *inode)
  73 {
  74         int rc;
  75
  76         rc = alloc_jfs_inode(inode);
  77         if (rc) {
  78                 jfs_warn("In jfs_read_inode, alloc_jfs_inode failed");
  79                 goto bad_inode;
  80         }
  81         jfs_info("In jfs_read_inode, inode = 0x%p", inode);
  82
  83         if (diRead(inode))
  84                 goto bad_inode_free;
  85
  86         if (S_ISREG(inode->i_mode)) {
  87                 inode->i_op = &jfs_file_inode_operations;
  88                 inode->i_fop = &jfs_file_operations;
  89                 inode->i_mapping->a_ops = &jfs_aops;
  90         } else if (S_ISDIR(inode->i_mode)) {
  91                 inode->i_op = &jfs_dir_inode_operations;
  92                 inode->i_fop = &jfs_dir_operations;
  93         } else if (S_ISLNK(inode->i_mode)) {
  94                 if (inode->i_size >= IDATASIZE) {
  95                         inode->i_op = &page_symlink_inode_operations;
  96                         inode->i_mapping->a_ops = &jfs_aops;
  97                 } else
  98                         inode->i_op = &jfs_symlink_inode_operations;
  99         } else {
 100                 inode->i_op = &jfs_file_inode_operations;
 101                 init_special_inode(inode, inode->i_mode,
 102                                    kdev_t_to_nr(inode->i_rdev));
 103         }
 104
 105         return;
 106
 107       bad_inode_free:
 108         free_jfs_inode(inode);
 109       bad_inode:
 110         make_bad_inode(inode);
 111 }
 112
 113 /* This define is from fs/open.c */
 114 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
 115
 116 /*
 117  * Workhorse of both fsync & write_inode
 118  */
 119 int jfs_commit_inode(struct inode *inode, int wait)
 120 {
 121         int rc = 0;
 122         tid_t tid;
 123         static int noisy = 5;
 124
 125         jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
 126
 127         /*
 128          * Don't commit if inode has been committed since last being
 129          * marked dirty, or if it has been deleted.
 130          */
 131         if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
 132                 return 0;
 133
 134         if (isReadOnly(inode)) {
 135                 /* kernel allows writes to devices on read-only
 136                  * partitions and may think inode is dirty
 137                  */
 138                 if (!special_file(inode->i_mode) && noisy) {
 139                         jfs_err("jfs_commit_inode(0x%p) called on "
 140                                    "read-only volume", inode);
 141                         jfs_err("Is remount racy?");
 142                         noisy--;
 143                 }
 144                 return 0;
 145         }
 146
 147         tid = txBegin(inode->i_sb, COMMIT_INODE);
 148         down(&JFS_IP(inode)->commit_sem);
 149
 150         /*
 151          * Retest inode state after taking commit_sem
 152          */
 153         if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
 154                 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
 155
 156         txEnd(tid);
 157         up(&JFS_IP(inode)->commit_sem);
 158         return rc;
 159 }
 160
 161 void jfs_write_inode(struct inode *inode, int wait)
 162 {
 163         if (test_cflag(COMMIT_Nolink, inode))
 164                 return;
 165         /*
 166          * If COMMIT_DIRTY is not set, the inode isn't really dirty.
 167          * It has been committed since the last change, but was still
 168          * on the dirty inode list.
 169          */
 170          if (!test_cflag(COMMIT_Dirty, inode)) {
 171                 /* Make sure committed changes hit the disk */
 172                 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
 173                 return;
 174          }
 175
 176         if (jfs_commit_inode(inode, wait)) {
 177                 jfs_err("jfs_write_inode: jfs_commit_inode failed!");
 178         }
 179 }
 180
 181 void jfs_delete_inode(struct inode *inode)
 182 {
 183         jfs_info("In jfs_delete_inode, inode = 0x%p", inode);
 184
 185         if (test_cflag(COMMIT_Freewmap, inode))
 186                 freeZeroLink(inode);
 187
 188         diFree(inode);
 189
 190         clear_inode(inode);
 191 }
 192
 193 void jfs_dirty_inode(struct inode *inode)
 194 {
 195         static int noisy = 5;
 196
 197         if (isReadOnly(inode)) {
 198                 if (!special_file(inode->i_mode) && noisy) {
 199                         /* kernel allows writes to devices on read-only
 200                          * partitions and may try to mark inode dirty
 201                          */
 202                         jfs_err("jfs_dirty_inode called on read-only volume");
 203                         jfs_err("Is remount racy?");
 204                         noisy--;
 205                 }
 206                 return;
 207         }
 208
 209         set_cflag(COMMIT_Dirty, inode);
 210 }
 211
 212 static int jfs_get_block(struct inode *ip, long lblock,
 213                          struct buffer_head *bh_result, int create)
 214 {
 215         s64 lblock64 = lblock;
 216         int rc = 0;
 217         int take_locks;
 218         xad_t xad;
 219         s64 xaddr;
 220         int xflag;
 221         s32 xlen;
 222
 223         /*
 224          * If this is a special inode (imap, dmap)
 225          * the lock should already be taken
 226          */
 227         take_locks = (JFS_IP(ip)->fileset != AGGREGATE_I);
 228
 229         /*
 230          * Take appropriate lock on inode
 231          */
 232         if (take_locks) {
 233                 if (create)
 234                         IWRITE_LOCK(ip);
 235                 else
 236                         IREAD_LOCK(ip);
 237         }
 238
 239         if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
 240             (xtLookup(ip, lblock64, 1, &xflag, &xaddr, &xlen, 0) == 0) &&
 241             xlen) {
 242                 if (xflag & XAD_NOTRECORDED) {
 243                         if (!create)
 244                                 /*
 245                                  * Allocated but not recorded, read treats
 246                                  * this as a hole
 247                                  */
 248                                 goto unlock;
 249 #ifdef _JFS_4K
 250                         XADoffset(&xad, lblock64);
 251                         XADlength(&xad, xlen);
 252                         XADaddress(&xad, xaddr);
 253 #else                           /* _JFS_4K */
 254                         /*
 255                          * As long as block size = 4K, this isn't a problem.
 256                          * We should mark the whole page not ABNR, but how
 257                          * will we know to mark the other blocks BH_New?
 258                          */
 259                         BUG();
 260 #endif                          /* _JFS_4K */
 261                         rc = extRecord(ip, &xad);
 262                         if (rc)
 263                                 goto unlock;
 264                         bh_result->b_state |= (1UL << BH_New);
 265                 }
 266
 267                 bh_result->b_dev = ip->i_dev;
 268                 bh_result->b_blocknr = xaddr;
 269                 bh_result->b_state |= (1UL << BH_Mapped);
 270                 goto unlock;
 271         }
 272         if (!create)
 273                 goto unlock;
 274
 275         /*
 276          * Allocate a new block
 277          */
 278 #ifdef _JFS_4K
 279         if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
 280                 goto unlock;
 281         rc = extAlloc(ip, 1, lblock64, &xad, FALSE);
 282         if (rc)
 283                 goto unlock;
 284
 285         bh_result->b_dev = ip->i_dev;
 286         bh_result->b_blocknr = addressXAD(&xad);
 287         bh_result->b_state |= ((1UL << BH_Mapped) | (1UL << BH_New));
 288
 289 #else                           /* _JFS_4K */
 290         /*
 291          * We need to do whatever it takes to keep all but the last buffers
 292          * in 4K pages - see jfs_write.c
 293          */
 294         BUG();
 295 #endif                          /* _JFS_4K */
 296
 297       unlock:
 298         /*
 299          * Release lock on inode
 300          */
 301         if (take_locks) {
 302                 if (create)
 303                         IWRITE_UNLOCK(ip);
 304                 else
 305                         IREAD_UNLOCK(ip);
 306         }
 307         return rc;
 308 }
 309
 310 static int jfs_writepage(struct page *page)
 311 {
 312         return block_write_full_page(page, jfs_get_block);
 313 }
 314
 315 static int jfs_readpage(struct file *file, struct page *page)
 316 {
 317         return block_read_full_page(page, jfs_get_block);
 318 }
 319
 320 static int jfs_prepare_write(struct file *file,
 321                              struct page *page, unsigned from, unsigned to)
 322 {
 323         return block_prepare_write(page, from, to, jfs_get_block);
 324 }
 325
 326 static int jfs_bmap(struct address_space *mapping, long block)
 327 {
 328         return generic_block_bmap(mapping, block, jfs_get_block);
 329 }
 330
 331 static int jfs_direct_IO(int rw, struct inode *inode, struct kiobuf *iobuf,
 332                          unsigned long blocknr, int blocksize)
 333 {
 334         return generic_direct_IO(rw, inode, iobuf, blocknr,
 335                                  blocksize, jfs_get_block);
 336 }
 337
 338 struct address_space_operations jfs_aops = {
 339         .readpage       = jfs_readpage,
 340         .writepage      = jfs_writepage,
 341         .sync_page      = block_sync_page,
 342         .prepare_write  = jfs_prepare_write,
 343         .commit_write   = generic_commit_write,
 344         .bmap           = jfs_bmap,
 345         .direct_IO      = jfs_direct_IO,
 346 };
 347
 348 /*
 349  * Guts of jfs_truncate.  Called with locks already held.  Can be called
 350  * with directory for truncating directory index table.
 351  */
 352 void jfs_truncate_nolock(struct inode *ip, loff_t length)
 353 {
 354         loff_t newsize;
 355         tid_t tid;
 356
 357         ASSERT(length >= 0);
 358
 359         if (test_cflag(COMMIT_Nolink, ip)) {
 360                 xtTruncate(0, ip, length, COMMIT_WMAP);
 361                 return;
 362         }
 363
 364         do {
 365                 tid = txBegin(ip->i_sb, 0);
 366
 367                 /*
 368                  * The commit_sem cannot be taken before txBegin.
 369                  * txBegin may block and there is a chance the inode
 370                  * could be marked dirty and need to be committed
 371                  * before txBegin unblocks
 372                  */
 373                 down(&JFS_IP(ip)->commit_sem);
 374
 375                 newsize = xtTruncate(tid, ip, length,
 376                                      COMMIT_TRUNCATE | COMMIT_PWMAP);
 377                 if (newsize < 0) {
 378                         txEnd(tid);
 379                         up(&JFS_IP(ip)->commit_sem);
 380                         break;
 381                 }
 382
 383                 ip->i_mtime = ip->i_ctime = CURRENT_TIME;
 384                 mark_inode_dirty(ip);
 385
 386                 txCommit(tid, 1, &ip, 0);
 387                 txEnd(tid);
 388                 up(&JFS_IP(ip)->commit_sem);
 389         } while (newsize > length);     /* Truncate isn't always atomic */
 390 }
 391
 392 void jfs_truncate(struct inode *ip)
 393 {
 394         jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
 395
 396         block_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
 397
 398         IWRITE_LOCK(ip);
 399         jfs_truncate_nolock(ip, ip->i_size);
 400         IWRITE_UNLOCK(ip);
 401 }