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/uio.h> 26 #include <linux/writeback.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 36 struct 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 inode->i_link = JFS_IP(inode)->i_inline; 67 /* 68 * The inline data should be null-terminated, but 69 * don't let on-disk corruption crash the kernel 70 */ 71 inode->i_link[inode->i_size] = '\0'; 72 } 73 } else { 74 inode->i_op = &jfs_file_inode_operations; 75 init_special_inode(inode, inode->i_mode, inode->i_rdev); 76 } 77 unlock_new_inode(inode); 78 return inode; 79 } 80 81 /* 82 * Workhorse of both fsync & write_inode 83 */ 84 int jfs_commit_inode(struct inode *inode, int wait) 85 { 86 int rc = 0; 87 tid_t tid; 88 static int noisy = 5; 89 90 jfs_info("In jfs_commit_inode, inode = 0x%p", inode); 91 92 /* 93 * Don't commit if inode has been committed since last being 94 * marked dirty, or if it has been deleted. 95 */ 96 if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode)) 97 return 0; 98 99 if (isReadOnly(inode)) { 100 /* kernel allows writes to devices on read-only 101 * partitions and may think inode is dirty 102 */ 103 if (!special_file(inode->i_mode) && noisy) { 104 jfs_err("jfs_commit_inode(0x%p) called on " 105 "read-only volume", inode); 106 jfs_err("Is remount racy?"); 107 noisy--; 108 } 109 return 0; 110 } 111 112 tid = txBegin(inode->i_sb, COMMIT_INODE); 113 mutex_lock(&JFS_IP(inode)->commit_mutex); 114 115 /* 116 * Retest inode state after taking commit_mutex 117 */ 118 if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode)) 119 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0); 120 121 txEnd(tid); 122 mutex_unlock(&JFS_IP(inode)->commit_mutex); 123 return rc; 124 } 125 126 int jfs_write_inode(struct inode *inode, struct writeback_control *wbc) 127 { 128 int wait = wbc->sync_mode == WB_SYNC_ALL; 129 130 if (inode->i_nlink == 0) 131 return 0; 132 /* 133 * If COMMIT_DIRTY is not set, the inode isn't really dirty. 134 * It has been committed since the last change, but was still 135 * on the dirty inode list. 136 */ 137 if (!test_cflag(COMMIT_Dirty, inode)) { 138 /* Make sure committed changes hit the disk */ 139 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait); 140 return 0; 141 } 142 143 if (jfs_commit_inode(inode, wait)) { 144 jfs_err("jfs_write_inode: jfs_commit_inode failed!"); 145 return -EIO; 146 } else 147 return 0; 148 } 149 150 void jfs_evict_inode(struct inode *inode) 151 { 152 jfs_info("In jfs_evict_inode, inode = 0x%p", inode); 153 154 if (!inode->i_nlink && !is_bad_inode(inode)) { 155 dquot_initialize(inode); 156 157 if (JFS_IP(inode)->fileset == FILESYSTEM_I) { 158 truncate_inode_pages_final(&inode->i_data); 159 160 if (test_cflag(COMMIT_Freewmap, inode)) 161 jfs_free_zero_link(inode); 162 163 diFree(inode); 164 165 /* 166 * Free the inode from the quota allocation. 167 */ 168 dquot_initialize(inode); 169 dquot_free_inode(inode); 170 } 171 } else { 172 truncate_inode_pages_final(&inode->i_data); 173 } 174 clear_inode(inode); 175 dquot_drop(inode); 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 int jfs_readpages(struct file *file, struct address_space *mapping, 300 struct list_head *pages, unsigned nr_pages) 301 { 302 return mpage_readpages(mapping, pages, nr_pages, jfs_get_block); 303 } 304 305 static void jfs_write_failed(struct address_space *mapping, loff_t to) 306 { 307 struct inode *inode = mapping->host; 308 309 if (to > inode->i_size) { 310 truncate_pagecache(inode, inode->i_size); 311 jfs_truncate(inode); 312 } 313 } 314 315 static int jfs_write_begin(struct file *file, struct address_space *mapping, 316 loff_t pos, unsigned len, unsigned flags, 317 struct page **pagep, void **fsdata) 318 { 319 int ret; 320 321 ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata, 322 jfs_get_block); 323 if (unlikely(ret)) 324 jfs_write_failed(mapping, pos + len); 325 326 return ret; 327 } 328 329 static sector_t jfs_bmap(struct address_space *mapping, sector_t block) 330 { 331 return generic_block_bmap(mapping, block, jfs_get_block); 332 } 333 334 static ssize_t jfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter, 335 loff_t offset) 336 { 337 struct file *file = iocb->ki_filp; 338 struct address_space *mapping = file->f_mapping; 339 struct inode *inode = file->f_mapping->host; 340 size_t count = iov_iter_count(iter); 341 ssize_t ret; 342 343 ret = blockdev_direct_IO(iocb, inode, iter, offset, jfs_get_block); 344 345 /* 346 * In case of error extending write may have instantiated a few 347 * blocks outside i_size. Trim these off again. 348 */ 349 if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) { 350 loff_t isize = i_size_read(inode); 351 loff_t end = offset + count; 352 353 if (end > isize) 354 jfs_write_failed(mapping, end); 355 } 356 357 return ret; 358 } 359 360 const struct address_space_operations jfs_aops = { 361 .readpage = jfs_readpage, 362 .readpages = jfs_readpages, 363 .writepage = jfs_writepage, 364 .writepages = jfs_writepages, 365 .write_begin = jfs_write_begin, 366 .write_end = nobh_write_end, 367 .bmap = jfs_bmap, 368 .direct_IO = jfs_direct_IO, 369 }; 370 371 /* 372 * Guts of jfs_truncate. Called with locks already held. Can be called 373 * with directory for truncating directory index table. 374 */ 375 void jfs_truncate_nolock(struct inode *ip, loff_t length) 376 { 377 loff_t newsize; 378 tid_t tid; 379 380 ASSERT(length >= 0); 381 382 if (test_cflag(COMMIT_Nolink, ip)) { 383 xtTruncate(0, ip, length, COMMIT_WMAP); 384 return; 385 } 386 387 do { 388 tid = txBegin(ip->i_sb, 0); 389 390 /* 391 * The commit_mutex cannot be taken before txBegin. 392 * txBegin may block and there is a chance the inode 393 * could be marked dirty and need to be committed 394 * before txBegin unblocks 395 */ 396 mutex_lock(&JFS_IP(ip)->commit_mutex); 397 398 newsize = xtTruncate(tid, ip, length, 399 COMMIT_TRUNCATE | COMMIT_PWMAP); 400 if (newsize < 0) { 401 txEnd(tid); 402 mutex_unlock(&JFS_IP(ip)->commit_mutex); 403 break; 404 } 405 406 ip->i_mtime = ip->i_ctime = CURRENT_TIME; 407 mark_inode_dirty(ip); 408 409 txCommit(tid, 1, &ip, 0); 410 txEnd(tid); 411 mutex_unlock(&JFS_IP(ip)->commit_mutex); 412 } while (newsize > length); /* Truncate isn't always atomic */ 413 } 414 415 void jfs_truncate(struct inode *ip) 416 { 417 jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size); 418 419 nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block); 420 421 IWRITE_LOCK(ip, RDWRLOCK_NORMAL); 422 jfs_truncate_nolock(ip, ip->i_size); 423 IWRITE_UNLOCK(ip); 424 } 425