fs/jfs/inode.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) International Business Machines Corp., 2000-2004
   4  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
   5  */
   6
   7 #include <linux/fs.h>
   8 #include <linux/mpage.h>
   9 #include <linux/buffer_head.h>
  10 #include <linux/pagemap.h>
  11 #include <linux/quotaops.h>
  12 #include <linux/uio.h>
  13 #include <linux/writeback.h>
  14 #include "jfs_incore.h"
  15 #include "jfs_inode.h"
  16 #include "jfs_filsys.h"
  17 #include "jfs_imap.h"
  18 #include "jfs_extent.h"
  19 #include "jfs_unicode.h"
  20 #include "jfs_debug.h"
  21 #include "jfs_dmap.h"
  22
  23
  24 struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
  25 {
  26         struct inode *inode;
  27         int ret;
  28
  29         inode = iget_locked(sb, ino);
  30         if (!inode)
  31                 return ERR_PTR(-ENOMEM);
  32         if (!(inode->i_state & I_NEW))
  33                 return inode;
  34
  35         ret = diRead(inode);
  36         if (ret < 0) {
  37                 iget_failed(inode);
  38                 return ERR_PTR(ret);
  39         }
  40
  41         if (S_ISREG(inode->i_mode)) {
  42                 inode->i_op = &jfs_file_inode_operations;
  43                 inode->i_fop = &jfs_file_operations;
  44                 inode->i_mapping->a_ops = &jfs_aops;
  45         } else if (S_ISDIR(inode->i_mode)) {
  46                 inode->i_op = &jfs_dir_inode_operations;
  47                 inode->i_fop = &jfs_dir_operations;
  48         } else if (S_ISLNK(inode->i_mode)) {
  49                 if (inode->i_size >= IDATASIZE) {
  50                         inode->i_op = &page_symlink_inode_operations;
  51                         inode_nohighmem(inode);
  52                         inode->i_mapping->a_ops = &jfs_aops;
  53                 } else {
  54                         inode->i_op = &jfs_fast_symlink_inode_operations;
  55                         inode->i_link = JFS_IP(inode)->i_inline;
  56                         /*
  57                          * The inline data should be null-terminated, but
  58                          * don't let on-disk corruption crash the kernel
  59                          */
  60                         inode->i_link[inode->i_size] = '\0';
  61                 }
  62         } else {
  63                 inode->i_op = &jfs_file_inode_operations;
  64                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
  65         }
  66         unlock_new_inode(inode);
  67         return inode;
  68 }
  69
  70 /*
  71  * Workhorse of both fsync & write_inode
  72  */
  73 int jfs_commit_inode(struct inode *inode, int wait)
  74 {
  75         int rc = 0;
  76         tid_t tid;
  77         static int noisy = 5;
  78
  79         jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
  80
  81         /*
  82          * Don't commit if inode has been committed since last being
  83          * marked dirty, or if it has been deleted.
  84          */
  85         if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
  86                 return 0;
  87
  88         if (isReadOnly(inode)) {
  89                 /* kernel allows writes to devices on read-only
  90                  * partitions and may think inode is dirty
  91                  */
  92                 if (!special_file(inode->i_mode) && noisy) {
  93                         jfs_err("jfs_commit_inode(0x%p) called on read-only volume",
  94                                 inode);
  95                         jfs_err("Is remount racy?");
  96                         noisy--;
  97                 }
  98                 return 0;
  99         }
 100
 101         tid = txBegin(inode->i_sb, COMMIT_INODE);
 102         mutex_lock(&JFS_IP(inode)->commit_mutex);
 103
 104         /*
 105          * Retest inode state after taking commit_mutex
 106          */
 107         if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
 108                 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
 109
 110         txEnd(tid);
 111         mutex_unlock(&JFS_IP(inode)->commit_mutex);
 112         return rc;
 113 }
 114
 115 int jfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 116 {
 117         int wait = wbc->sync_mode == WB_SYNC_ALL;
 118
 119         if (inode->i_nlink == 0)
 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_evict_inode(struct inode *inode)
 140 {
 141         struct jfs_inode_info *ji = JFS_IP(inode);
 142
 143         jfs_info("In jfs_evict_inode, inode = 0x%p", inode);
 144
 145         if (!inode->i_nlink && !is_bad_inode(inode)) {
 146                 dquot_initialize(inode);
 147
 148                 if (JFS_IP(inode)->fileset == FILESYSTEM_I) {
 149                         truncate_inode_pages_final(&inode->i_data);
 150
 151                         if (test_cflag(COMMIT_Freewmap, inode))
 152                                 jfs_free_zero_link(inode);
 153
 154                         diFree(inode);
 155
 156                         /*
 157                          * Free the inode from the quota allocation.
 158                          */
 159                         dquot_free_inode(inode);
 160                 }
 161         } else {
 162                 truncate_inode_pages_final(&inode->i_data);
 163         }
 164         clear_inode(inode);
 165         dquot_drop(inode);
 166
 167         BUG_ON(!list_empty(&ji->anon_inode_list));
 168
 169         spin_lock_irq(&ji->ag_lock);
 170         if (ji->active_ag != -1) {
 171                 struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
 172                 atomic_dec(&bmap->db_active[ji->active_ag]);
 173                 ji->active_ag = -1;
 174         }
 175         spin_unlock_irq(&ji->ag_lock);
 176 }
 177
 178 void jfs_dirty_inode(struct inode *inode, int flags)
 179 {
 180         static int noisy = 5;
 181
 182         if (isReadOnly(inode)) {
 183                 if (!special_file(inode->i_mode) && noisy) {
 184                         /* kernel allows writes to devices on read-only
 185                          * partitions and may try to mark inode dirty
 186                          */
 187                         jfs_err("jfs_dirty_inode called on read-only volume");
 188                         jfs_err("Is remount racy?");
 189                         noisy--;
 190                 }
 191                 return;
 192         }
 193
 194         set_cflag(COMMIT_Dirty, inode);
 195 }
 196
 197 int jfs_get_block(struct inode *ip, sector_t lblock,
 198                   struct buffer_head *bh_result, int create)
 199 {
 200         s64 lblock64 = lblock;
 201         int rc = 0;
 202         xad_t xad;
 203         s64 xaddr;
 204         int xflag;
 205         s32 xlen = bh_result->b_size >> ip->i_blkbits;
 206
 207         /*
 208          * Take appropriate lock on inode
 209          */
 210         if (create)
 211                 IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 212         else
 213                 IREAD_LOCK(ip, RDWRLOCK_NORMAL);
 214
 215         if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
 216             (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
 217             xaddr) {
 218                 if (xflag & XAD_NOTRECORDED) {
 219                         if (!create)
 220                                 /*
 221                                  * Allocated but not recorded, read treats
 222                                  * this as a hole
 223                                  */
 224                                 goto unlock;
 225 #ifdef _JFS_4K
 226                         XADoffset(&xad, lblock64);
 227                         XADlength(&xad, xlen);
 228                         XADaddress(&xad, xaddr);
 229 #else                           /* _JFS_4K */
 230                         /*
 231                          * As long as block size = 4K, this isn't a problem.
 232                          * We should mark the whole page not ABNR, but how
 233                          * will we know to mark the other blocks BH_New?
 234                          */
 235                         BUG();
 236 #endif                          /* _JFS_4K */
 237                         rc = extRecord(ip, &xad);
 238                         if (rc)
 239                                 goto unlock;
 240                         set_buffer_new(bh_result);
 241                 }
 242
 243                 map_bh(bh_result, ip->i_sb, xaddr);
 244                 bh_result->b_size = xlen << ip->i_blkbits;
 245                 goto unlock;
 246         }
 247         if (!create)
 248                 goto unlock;
 249
 250         /*
 251          * Allocate a new block
 252          */
 253 #ifdef _JFS_4K
 254         if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
 255                 goto unlock;
 256         rc = extAlloc(ip, xlen, lblock64, &xad, false);
 257         if (rc)
 258                 goto unlock;
 259
 260         set_buffer_new(bh_result);
 261         map_bh(bh_result, ip->i_sb, addressXAD(&xad));
 262         bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
 263
 264 #else                           /* _JFS_4K */
 265         /*
 266          * We need to do whatever it takes to keep all but the last buffers
 267          * in 4K pages - see jfs_write.c
 268          */
 269         BUG();
 270 #endif                          /* _JFS_4K */
 271
 272       unlock:
 273         /*
 274          * Release lock on inode
 275          */
 276         if (create)
 277                 IWRITE_UNLOCK(ip);
 278         else
 279                 IREAD_UNLOCK(ip);
 280         return rc;
 281 }
 282
 283 static int jfs_writepage(struct page *page, struct writeback_control *wbc)
 284 {
 285         return block_write_full_page(page, jfs_get_block, wbc);
 286 }
 287
 288 static int jfs_writepages(struct address_space *mapping,
 289                         struct writeback_control *wbc)
 290 {
 291         return mpage_writepages(mapping, wbc, jfs_get_block);
 292 }
 293
 294 static int jfs_readpage(struct file *file, struct page *page)
 295 {
 296         return mpage_readpage(page, jfs_get_block);
 297 }
 298
 299 static void jfs_readahead(struct readahead_control *rac)
 300 {
 301         mpage_readahead(rac, jfs_get_block);
 302 }
 303
 304 static 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
 314 static 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
 328 static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
 329 {
 330         return generic_block_bmap(mapping, block, jfs_get_block);
 331 }
 332
 333 static ssize_t jfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 334 {
 335         struct file *file = iocb->ki_filp;
 336         struct address_space *mapping = file->f_mapping;
 337         struct inode *inode = file->f_mapping->host;
 338         size_t count = iov_iter_count(iter);
 339         ssize_t ret;
 340
 341         ret = blockdev_direct_IO(iocb, inode, iter, jfs_get_block);
 342
 343         /*
 344          * In case of error extending write may have instantiated a few
 345          * blocks outside i_size. Trim these off again.
 346          */
 347         if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
 348                 loff_t isize = i_size_read(inode);
 349                 loff_t end = iocb->ki_pos + count;
 350
 351                 if (end > isize)
 352                         jfs_write_failed(mapping, end);
 353         }
 354
 355         return ret;
 356 }
 357
 358 const struct address_space_operations jfs_aops = {
 359         .readpage       = jfs_readpage,
 360         .readahead      = jfs_readahead,
 361         .writepage      = jfs_writepage,
 362         .writepages     = jfs_writepages,
 363         .write_begin    = jfs_write_begin,
 364         .write_end      = nobh_write_end,
 365         .bmap           = jfs_bmap,
 366         .direct_IO      = jfs_direct_IO,
 367 };
 368
 369 /*
 370  * Guts of jfs_truncate.  Called with locks already held.  Can be called
 371  * with directory for truncating directory index table.
 372  */
 373 void jfs_truncate_nolock(struct inode *ip, loff_t length)
 374 {
 375         loff_t newsize;
 376         tid_t tid;
 377
 378         ASSERT(length >= 0);
 379
 380         if (test_cflag(COMMIT_Nolink, ip)) {
 381                 xtTruncate(0, ip, length, COMMIT_WMAP);
 382                 return;
 383         }
 384
 385         do {
 386                 tid = txBegin(ip->i_sb, 0);
 387
 388                 /*
 389                  * The commit_mutex cannot be taken before txBegin.
 390                  * txBegin may block and there is a chance the inode
 391                  * could be marked dirty and need to be committed
 392                  * before txBegin unblocks
 393                  */
 394                 mutex_lock(&JFS_IP(ip)->commit_mutex);
 395
 396                 newsize = xtTruncate(tid, ip, length,
 397                                      COMMIT_TRUNCATE | COMMIT_PWMAP);
 398                 if (newsize < 0) {
 399                         txEnd(tid);
 400                         mutex_unlock(&JFS_IP(ip)->commit_mutex);
 401                         break;
 402                 }
 403
 404                 ip->i_mtime = ip->i_ctime = current_time(ip);
 405                 mark_inode_dirty(ip);
 406
 407                 txCommit(tid, 1, &ip, 0);
 408                 txEnd(tid);
 409                 mutex_unlock(&JFS_IP(ip)->commit_mutex);
 410         } while (newsize > length);     /* Truncate isn't always atomic */
 411 }
 412
 413 void jfs_truncate(struct inode *ip)
 414 {
 415         jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
 416
 417         nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
 418
 419         IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
 420         jfs_truncate_nolock(ip, ip->i_size);
 421         IWRITE_UNLOCK(ip);
 422 }