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 <linux/writeback.h>
  26 #include "jfs_incore.h"
  27 #include "jfs_inode.h"
  28 #include "jfs_filsys.h"
  29 #include "jfs_imap.h"
  30 #include "jfs_extent.h"
  31 #include "jfs_unicode.h"
  32 #include "jfs_debug.h"
  33
  34
  35 struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
  36 {
  37         struct inode *inode;
  38         int ret;
  39
  40         inode = iget_locked(sb, ino);
  41         if (!inode)
  42                 return ERR_PTR(-ENOMEM);
  43         if (!(inode->i_state & I_NEW))
  44                 return inode;
  45
  46         ret = diRead(inode);
  47         if (ret < 0) {
  48                 iget_failed(inode);
  49                 return ERR_PTR(ret);
  50         }
  51
  52         if (S_ISREG(inode->i_mode)) {
  53                 inode->i_op = &jfs_file_inode_operations;
  54                 inode->i_fop = &jfs_file_operations;
  55                 inode->i_mapping->a_ops = &jfs_aops;
  56         } else if (S_ISDIR(inode->i_mode)) {
  57                 inode->i_op = &jfs_dir_inode_operations;
  58                 inode->i_fop = &jfs_dir_operations;
  59         } else if (S_ISLNK(inode->i_mode)) {
  60                 if (inode->i_size >= IDATASIZE) {
  61                         inode->i_op = &page_symlink_inode_operations;
  62                         inode->i_mapping->a_ops = &jfs_aops;
  63                 } else {
  64                         inode->i_op = &jfs_symlink_inode_operations;
  65                         /*
  66                          * The inline data should be null-terminated, but
  67                          * don't let on-disk corruption crash the kernel
  68                          */
  69                         JFS_IP(inode)->i_inline[inode->i_size] = '\0';
  70                 }
  71         } else {
  72                 inode->i_op = &jfs_file_inode_operations;
  73                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
  74         }
  75         unlock_new_inode(inode);
  76         return inode;
  77 }
  78
  79 /*
  80  * Workhorse of both fsync & write_inode
  81  */
  82 int jfs_commit_inode(struct inode *inode, int wait)
  83 {
  84         int rc = 0;
  85         tid_t tid;
  86         static int noisy = 5;
  87
  88         jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
  89
  90         /*
  91          * Don't commit if inode has been committed since last being
  92          * marked dirty, or if it has been deleted.
  93          */
  94         if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
  95                 return 0;
  96
  97         if (isReadOnly(inode)) {
  98                 /* kernel allows writes to devices on read-only
  99                  * partitions and may think inode is dirty
 100                  */
 101                 if (!special_file(inode->i_mode) && noisy) {
 102                         jfs_err("jfs_commit_inode(0x%p) called on "
 103                                    "read-only volume", inode);
 104                         jfs_err("Is remount racy?");
 105                         noisy--;
 106                 }
 107                 return 0;
 108         }
 109
 110         tid = txBegin(inode->i_sb, COMMIT_INODE);
 111         mutex_lock(&JFS_IP(inode)->commit_mutex);
 112
 113         /*
 114          * Retest inode state after taking commit_mutex
 115          */
 116         if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
 117                 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
 118
 119         txEnd(tid);
 120         mutex_unlock(&JFS_IP(inode)->commit_mutex);
 121         return rc;
 122 }
 123
 124 int jfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 125 {
 126         int wait = wbc->sync_mode == WB_SYNC_ALL;
 127
 128         if (test_cflag(COMMIT_Nolink, inode))
 129                 return 0;
 130         /*
 131          * If COMMIT_DIRTY is not set, the inode isn't really dirty.
 132          * It has been committed since the last change, but was still
 133          * on the dirty inode list.
 134          */
 135          if (!test_cflag(COMMIT_Dirty, inode)) {
 136                 /* Make sure committed changes hit the disk */
 137                 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
 138                 return 0;
 139          }
 140
 141         if (jfs_commit_inode(inode, wait)) {
 142                 jfs_err("jfs_write_inode: jfs_commit_inode failed!");
 143                 return -EIO;
 144         } else
 145                 return 0;
 146 }
 147
 148 void jfs_delete_inode(struct inode *inode)
 149 {
 150         jfs_info("In jfs_delete_inode, inode = 0x%p", inode);
 151
 152         if (!is_bad_inode(inode) &&
 153             (JFS_IP(inode)->fileset == FILESYSTEM_I)) {
 154                 truncate_inode_pages(&inode->i_data, 0);
 155
 156                 if (test_cflag(COMMIT_Freewmap, inode))
 157                         jfs_free_zero_link(inode);
 158
 159                 diFree(inode);
 160
 161                 /*
 162                  * Free the inode from the quota allocation.
 163                  */
 164                 vfs_dq_init(inode);
 165                 vfs_dq_free_inode(inode);
 166                 vfs_dq_drop(inode);
 167         }
 168
 169         clear_inode(inode);
 170 }
 171
 172 void jfs_dirty_inode(struct inode *inode)
 173 {
 174         static int noisy = 5;
 175
 176         if (isReadOnly(inode)) {
 177                 if (!special_file(inode->i_mode) && noisy) {
 178                         /* kernel allows writes to devices on read-only
 179                          * partitions and may try to mark inode dirty
 180                          */
 181                         jfs_err("jfs_dirty_inode called on read-only volume");
 182                         jfs_err("Is remount racy?");
 183                         noisy--;
 184                 }
 185                 return;
 186         }
 187
 188         set_cflag(COMMIT_Dirty, inode);
 189 }
 190
 191 int jfs_get_block(struct inode *ip, sector_t lblock,
 192                   struct buffer_head *bh_result, int create)
 193 {
 194         s64 lblock64 = lblock;
 195         int rc = 0;
 196         xad_t xad;
 197         s64 xaddr;
 198         int xflag;
 199         s32 xlen = bh_result->b_size >> ip->i_blkbits;
 200
 201         /*
 202          * Take appropriate lock on inode
 203          */
 204         if (create)
 205                 IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 206         else
 207                 IREAD_LOCK(ip, RDWRLOCK_NORMAL);
 208
 209         if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
 210             (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
 211             xaddr) {
 212                 if (xflag & XAD_NOTRECORDED) {
 213                         if (!create)
 214                                 /*
 215                                  * Allocated but not recorded, read treats
 216                                  * this as a hole
 217                                  */
 218                                 goto unlock;
 219 #ifdef _JFS_4K
 220                         XADoffset(&xad, lblock64);
 221                         XADlength(&xad, xlen);
 222                         XADaddress(&xad, xaddr);
 223 #else                           /* _JFS_4K */
 224                         /*
 225                          * As long as block size = 4K, this isn't a problem.
 226                          * We should mark the whole page not ABNR, but how
 227                          * will we know to mark the other blocks BH_New?
 228                          */
 229                         BUG();
 230 #endif                          /* _JFS_4K */
 231                         rc = extRecord(ip, &xad);
 232                         if (rc)
 233                                 goto unlock;
 234                         set_buffer_new(bh_result);
 235                 }
 236
 237                 map_bh(bh_result, ip->i_sb, xaddr);
 238                 bh_result->b_size = xlen << ip->i_blkbits;
 239                 goto unlock;
 240         }
 241         if (!create)
 242                 goto unlock;
 243
 244         /*
 245          * Allocate a new block
 246          */
 247 #ifdef _JFS_4K
 248         if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
 249                 goto unlock;
 250         rc = extAlloc(ip, xlen, lblock64, &xad, false);
 251         if (rc)
 252                 goto unlock;
 253
 254         set_buffer_new(bh_result);
 255         map_bh(bh_result, ip->i_sb, addressXAD(&xad));
 256         bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
 257
 258 #else                           /* _JFS_4K */
 259         /*
 260          * We need to do whatever it takes to keep all but the last buffers
 261          * in 4K pages - see jfs_write.c
 262          */
 263         BUG();
 264 #endif                          /* _JFS_4K */
 265
 266       unlock:
 267         /*
 268          * Release lock on inode
 269          */
 270         if (create)
 271                 IWRITE_UNLOCK(ip);
 272         else
 273                 IREAD_UNLOCK(ip);
 274         return rc;
 275 }
 276
 277 static int jfs_writepage(struct page *page, struct writeback_control *wbc)
 278 {
 279         return block_write_full_page(page, jfs_get_block, wbc);
 280 }
 281
 282 static int jfs_writepages(struct address_space *mapping,
 283                         struct writeback_control *wbc)
 284 {
 285         return mpage_writepages(mapping, wbc, jfs_get_block);
 286 }
 287
 288 static int jfs_readpage(struct file *file, struct page *page)
 289 {
 290         return mpage_readpage(page, jfs_get_block);
 291 }
 292
 293 static int jfs_readpages(struct file *file, struct address_space *mapping,
 294                 struct list_head *pages, unsigned nr_pages)
 295 {
 296         return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
 297 }
 298
 299 static int jfs_write_begin(struct file *file, struct address_space *mapping,
 300                                 loff_t pos, unsigned len, unsigned flags,
 301                                 struct page **pagep, void **fsdata)
 302 {
 303         return nobh_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
 304                                 jfs_get_block);
 305 }
 306
 307 static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
 308 {
 309         return generic_block_bmap(mapping, block, jfs_get_block);
 310 }
 311
 312 static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 313         const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 314 {
 315         struct file *file = iocb->ki_filp;
 316         struct inode *inode = file->f_mapping->host;
 317
 318         return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 319                                 offset, nr_segs, jfs_get_block, NULL);
 320 }
 321
 322 const struct address_space_operations jfs_aops = {
 323         .readpage       = jfs_readpage,
 324         .readpages      = jfs_readpages,
 325         .writepage      = jfs_writepage,
 326         .writepages     = jfs_writepages,
 327         .sync_page      = block_sync_page,
 328         .write_begin    = jfs_write_begin,
 329         .write_end      = nobh_write_end,
 330         .bmap           = jfs_bmap,
 331         .direct_IO      = jfs_direct_IO,
 332 };
 333
 334 /*
 335  * Guts of jfs_truncate.  Called with locks already held.  Can be called
 336  * with directory for truncating directory index table.
 337  */
 338 void jfs_truncate_nolock(struct inode *ip, loff_t length)
 339 {
 340         loff_t newsize;
 341         tid_t tid;
 342
 343         ASSERT(length >= 0);
 344
 345         if (test_cflag(COMMIT_Nolink, ip)) {
 346                 xtTruncate(0, ip, length, COMMIT_WMAP);
 347                 return;
 348         }
 349
 350         do {
 351                 tid = txBegin(ip->i_sb, 0);
 352
 353                 /*
 354                  * The commit_mutex cannot be taken before txBegin.
 355                  * txBegin may block and there is a chance the inode
 356                  * could be marked dirty and need to be committed
 357                  * before txBegin unblocks
 358                  */
 359                 mutex_lock(&JFS_IP(ip)->commit_mutex);
 360
 361                 newsize = xtTruncate(tid, ip, length,
 362                                      COMMIT_TRUNCATE | COMMIT_PWMAP);
 363                 if (newsize < 0) {
 364                         txEnd(tid);
 365                         mutex_unlock(&JFS_IP(ip)->commit_mutex);
 366                         break;
 367                 }
 368
 369                 ip->i_mtime = ip->i_ctime = CURRENT_TIME;
 370                 mark_inode_dirty(ip);
 371
 372                 txCommit(tid, 1, &ip, 0);
 373                 txEnd(tid);
 374                 mutex_unlock(&JFS_IP(ip)->commit_mutex);
 375         } while (newsize > length);     /* Truncate isn't always atomic */
 376 }
 377
 378 void jfs_truncate(struct inode *ip)
 379 {
 380         jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
 381
 382         nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
 383
 384         IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 385         jfs_truncate_nolock(ip, ip->i_size);
 386         IWRITE_UNLOCK(ip);
 387 }