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