linux/fs/jfs/inode.c
<<
>>
Prefs
   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 <linux/aio.h>
  27#include "jfs_incore.h"
  28#include "jfs_inode.h"
  29#include "jfs_filsys.h"
  30#include "jfs_imap.h"
  31#include "jfs_extent.h"
  32#include "jfs_unicode.h"
  33#include "jfs_debug.h"
  34
  35
  36struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
  37{
  38        struct inode *inode;
  39        int ret;
  40
  41        inode = iget_locked(sb, ino);
  42        if (!inode)
  43                return ERR_PTR(-ENOMEM);
  44        if (!(inode->i_state & I_NEW))
  45                return inode;
  46
  47        ret = diRead(inode);
  48        if (ret < 0) {
  49                iget_failed(inode);
  50                return ERR_PTR(ret);
  51        }
  52
  53        if (S_ISREG(inode->i_mode)) {
  54                inode->i_op = &jfs_file_inode_operations;
  55                inode->i_fop = &jfs_file_operations;
  56                inode->i_mapping->a_ops = &jfs_aops;
  57        } else if (S_ISDIR(inode->i_mode)) {
  58                inode->i_op = &jfs_dir_inode_operations;
  59                inode->i_fop = &jfs_dir_operations;
  60        } else if (S_ISLNK(inode->i_mode)) {
  61                if (inode->i_size >= IDATASIZE) {
  62                        inode->i_op = &page_symlink_inode_operations;
  63                        inode->i_mapping->a_ops = &jfs_aops;
  64                } else {
  65                        inode->i_op = &jfs_fast_symlink_inode_operations;
  66                        /*
  67                         * The inline data should be null-terminated, but
  68                         * don't let on-disk corruption crash the kernel
  69                         */
  70                        JFS_IP(inode)->i_inline[inode->i_size] = '\0';
  71                }
  72        } else {
  73                inode->i_op = &jfs_file_inode_operations;
  74                init_special_inode(inode, inode->i_mode, inode->i_rdev);
  75        }
  76        unlock_new_inode(inode);
  77        return inode;
  78}
  79
  80/*
  81 * Workhorse of both fsync & write_inode
  82 */
  83int jfs_commit_inode(struct inode *inode, int wait)
  84{
  85        int rc = 0;
  86        tid_t tid;
  87        static int noisy = 5;
  88
  89        jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
  90
  91        /*
  92         * Don't commit if inode has been committed since last being
  93         * marked dirty, or if it has been deleted.
  94         */
  95        if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
  96                return 0;
  97
  98        if (isReadOnly(inode)) {
  99                /* kernel allows writes to devices on read-only
 100                 * partitions and may think inode is dirty
 101                 */
 102                if (!special_file(inode->i_mode) && noisy) {
 103                        jfs_err("jfs_commit_inode(0x%p) called on "
 104                                   "read-only volume", inode);
 105                        jfs_err("Is remount racy?");
 106                        noisy--;
 107                }
 108                return 0;
 109        }
 110
 111        tid = txBegin(inode->i_sb, COMMIT_INODE);
 112        mutex_lock(&JFS_IP(inode)->commit_mutex);
 113
 114        /*
 115         * Retest inode state after taking commit_mutex
 116         */
 117        if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
 118                rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
 119
 120        txEnd(tid);
 121        mutex_unlock(&JFS_IP(inode)->commit_mutex);
 122        return rc;
 123}
 124
 125int jfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 126{
 127        int wait = wbc->sync_mode == WB_SYNC_ALL;
 128
 129        if (inode->i_nlink == 0)
 130                return 0;
 131        /*
 132         * If COMMIT_DIRTY is not set, the inode isn't really dirty.
 133         * It has been committed since the last change, but was still
 134         * on the dirty inode list.
 135         */
 136         if (!test_cflag(COMMIT_Dirty, inode)) {
 137                /* Make sure committed changes hit the disk */
 138                jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
 139                return 0;
 140         }
 141
 142        if (jfs_commit_inode(inode, wait)) {
 143                jfs_err("jfs_write_inode: jfs_commit_inode failed!");
 144                return -EIO;
 145        } else
 146                return 0;
 147}
 148
 149void jfs_evict_inode(struct inode *inode)
 150{
 151        jfs_info("In jfs_evict_inode, inode = 0x%p", inode);
 152
 153        if (!inode->i_nlink && !is_bad_inode(inode)) {
 154                dquot_initialize(inode);
 155
 156                if (JFS_IP(inode)->fileset == FILESYSTEM_I) {
 157                        truncate_inode_pages_final(&inode->i_data);
 158
 159                        if (test_cflag(COMMIT_Freewmap, inode))
 160                                jfs_free_zero_link(inode);
 161
 162                        diFree(inode);
 163
 164                        /*
 165                         * Free the inode from the quota allocation.
 166                         */
 167                        dquot_initialize(inode);
 168                        dquot_free_inode(inode);
 169                }
 170        } else {
 171                truncate_inode_pages_final(&inode->i_data);
 172        }
 173        clear_inode(inode);
 174        dquot_drop(inode);
 175}
 176
 177void jfs_dirty_inode(struct inode *inode, int flags)
 178{
 179        static int noisy = 5;
 180
 181        if (isReadOnly(inode)) {
 182                if (!special_file(inode->i_mode) && noisy) {
 183                        /* kernel allows writes to devices on read-only
 184                         * partitions and may try to mark inode dirty
 185                         */
 186                        jfs_err("jfs_dirty_inode called on read-only volume");
 187                        jfs_err("Is remount racy?");
 188                        noisy--;
 189                }
 190                return;
 191        }
 192
 193        set_cflag(COMMIT_Dirty, inode);
 194}
 195
 196int jfs_get_block(struct inode *ip, sector_t lblock,
 197                  struct buffer_head *bh_result, int create)
 198{
 199        s64 lblock64 = lblock;
 200        int rc = 0;
 201        xad_t xad;
 202        s64 xaddr;
 203        int xflag;
 204        s32 xlen = bh_result->b_size >> ip->i_blkbits;
 205
 206        /*
 207         * Take appropriate lock on inode
 208         */
 209        if (create)
 210                IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 211        else
 212                IREAD_LOCK(ip, RDWRLOCK_NORMAL);
 213
 214        if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
 215            (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
 216            xaddr) {
 217                if (xflag & XAD_NOTRECORDED) {
 218                        if (!create)
 219                                /*
 220                                 * Allocated but not recorded, read treats
 221                                 * this as a hole
 222                                 */
 223                                goto unlock;
 224#ifdef _JFS_4K
 225                        XADoffset(&xad, lblock64);
 226                        XADlength(&xad, xlen);
 227                        XADaddress(&xad, xaddr);
 228#else                           /* _JFS_4K */
 229                        /*
 230                         * As long as block size = 4K, this isn't a problem.
 231                         * We should mark the whole page not ABNR, but how
 232                         * will we know to mark the other blocks BH_New?
 233                         */
 234                        BUG();
 235#endif                          /* _JFS_4K */
 236                        rc = extRecord(ip, &xad);
 237                        if (rc)
 238                                goto unlock;
 239                        set_buffer_new(bh_result);
 240                }
 241
 242                map_bh(bh_result, ip->i_sb, xaddr);
 243                bh_result->b_size = xlen << ip->i_blkbits;
 244                goto unlock;
 245        }
 246        if (!create)
 247                goto unlock;
 248
 249        /*
 250         * Allocate a new block
 251         */
 252#ifdef _JFS_4K
 253        if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
 254                goto unlock;
 255        rc = extAlloc(ip, xlen, lblock64, &xad, false);
 256        if (rc)
 257                goto unlock;
 258
 259        set_buffer_new(bh_result);
 260        map_bh(bh_result, ip->i_sb, addressXAD(&xad));
 261        bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
 262
 263#else                           /* _JFS_4K */
 264        /*
 265         * We need to do whatever it takes to keep all but the last buffers
 266         * in 4K pages - see jfs_write.c
 267         */
 268        BUG();
 269#endif                          /* _JFS_4K */
 270
 271      unlock:
 272        /*
 273         * Release lock on inode
 274         */
 275        if (create)
 276                IWRITE_UNLOCK(ip);
 277        else
 278                IREAD_UNLOCK(ip);
 279        return rc;
 280}
 281
 282static int jfs_writepage(struct page *page, struct writeback_control *wbc)
 283{
 284        return block_write_full_page(page, jfs_get_block, wbc);
 285}
 286
 287static int jfs_writepages(struct address_space *mapping,
 288                        struct writeback_control *wbc)
 289{
 290        return mpage_writepages(mapping, wbc, jfs_get_block);
 291}
 292
 293static int jfs_readpage(struct file *file, struct page *page)
 294{
 295        return mpage_readpage(page, jfs_get_block);
 296}
 297
 298static int jfs_readpages(struct file *file, struct address_space *mapping,
 299                struct list_head *pages, unsigned nr_pages)
 300{
 301        return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
 302}
 303
 304static void jfs_write_failed(struct address_space *mapping, loff_t to)
 305{
 306        struct inode *inode = mapping->host;
 307
 308        if (to > inode->i_size) {
 309                truncate_pagecache(inode, inode->i_size);
 310                jfs_truncate(inode);
 311        }
 312}
 313
 314static int jfs_write_begin(struct file *file, struct address_space *mapping,
 315                                loff_t pos, unsigned len, unsigned flags,
 316                                struct page **pagep, void **fsdata)
 317{
 318        int ret;
 319
 320        ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
 321                                jfs_get_block);
 322        if (unlikely(ret))
 323                jfs_write_failed(mapping, pos + len);
 324
 325        return ret;
 326}
 327
 328static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
 329{
 330        return generic_block_bmap(mapping, block, jfs_get_block);
 331}
 332
 333static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 334        struct iov_iter *iter, loff_t offset)
 335{
 336        struct file *file = iocb->ki_filp;
 337        struct address_space *mapping = file->f_mapping;
 338        struct inode *inode = file->f_mapping->host;
 339        size_t count = iov_iter_count(iter);
 340        ssize_t ret;
 341
 342        ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, jfs_get_block);
 343
 344        /*
 345         * In case of error extending write may have instantiated a few
 346         * blocks outside i_size. Trim these off again.
 347         */
 348        if (unlikely((rw & WRITE) && ret < 0)) {
 349                loff_t isize = i_size_read(inode);
 350                loff_t end = offset + count;
 351
 352                if (end > isize)
 353                        jfs_write_failed(mapping, end);
 354        }
 355
 356        return ret;
 357}
 358
 359const struct address_space_operations jfs_aops = {
 360        .readpage       = jfs_readpage,
 361        .readpages      = jfs_readpages,
 362        .writepage      = jfs_writepage,
 363        .writepages     = jfs_writepages,
 364        .write_begin    = jfs_write_begin,
 365        .write_end      = nobh_write_end,
 366        .bmap           = jfs_bmap,
 367        .direct_IO      = jfs_direct_IO,
 368};
 369
 370/*
 371 * Guts of jfs_truncate.  Called with locks already held.  Can be called
 372 * with directory for truncating directory index table.
 373 */
 374void jfs_truncate_nolock(struct inode *ip, loff_t length)
 375{
 376        loff_t newsize;
 377        tid_t tid;
 378
 379        ASSERT(length >= 0);
 380
 381        if (test_cflag(COMMIT_Nolink, ip)) {
 382                xtTruncate(0, ip, length, COMMIT_WMAP);
 383                return;
 384        }
 385
 386        do {
 387                tid = txBegin(ip->i_sb, 0);
 388
 389                /*
 390                 * The commit_mutex cannot be taken before txBegin.
 391                 * txBegin may block and there is a chance the inode
 392                 * could be marked dirty and need to be committed
 393                 * before txBegin unblocks
 394                 */
 395                mutex_lock(&JFS_IP(ip)->commit_mutex);
 396
 397                newsize = xtTruncate(tid, ip, length,
 398                                     COMMIT_TRUNCATE | COMMIT_PWMAP);
 399                if (newsize < 0) {
 400                        txEnd(tid);
 401                        mutex_unlock(&JFS_IP(ip)->commit_mutex);
 402                        break;
 403                }
 404
 405                ip->i_mtime = ip->i_ctime = CURRENT_TIME;
 406                mark_inode_dirty(ip);
 407
 408                txCommit(tid, 1, &ip, 0);
 409                txEnd(tid);
 410                mutex_unlock(&JFS_IP(ip)->commit_mutex);
 411        } while (newsize > length);     /* Truncate isn't always atomic */
 412}
 413
 414void jfs_truncate(struct inode *ip)
 415{
 416        jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
 417
 418        nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
 419
 420        IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 421        jfs_truncate_nolock(ip, ip->i_size);
 422        IWRITE_UNLOCK(ip);
 423}
 424