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_filsys.h" 27 #include "jfs_imap.h" 28 #include "jfs_extent.h" 29 #include "jfs_unicode.h" 30 #include "jfs_debug.h" 31 32 33 extern struct inode_operations jfs_dir_inode_operations; 34 extern struct inode_operations jfs_file_inode_operations; 35 extern struct inode_operations jfs_symlink_inode_operations; 36 extern struct file_operations jfs_dir_operations; 37 extern struct file_operations jfs_file_operations; 38 struct address_space_operations jfs_aops; 39 extern int freeZeroLink(struct inode *); 40 41 void jfs_read_inode(struct inode *inode) 42 { 43 if (diRead(inode)) { 44 make_bad_inode(inode); 45 return; 46 } 47 48 if (S_ISREG(inode->i_mode)) { 49 inode->i_op = &jfs_file_inode_operations; 50 inode->i_fop = &jfs_file_operations; 51 inode->i_mapping->a_ops = &jfs_aops; 52 } else if (S_ISDIR(inode->i_mode)) { 53 inode->i_op = &jfs_dir_inode_operations; 54 inode->i_fop = &jfs_dir_operations; 55 } else if (S_ISLNK(inode->i_mode)) { 56 if (inode->i_size >= IDATASIZE) { 57 inode->i_op = &page_symlink_inode_operations; 58 inode->i_mapping->a_ops = &jfs_aops; 59 } else 60 inode->i_op = &jfs_symlink_inode_operations; 61 } else { 62 inode->i_op = &jfs_file_inode_operations; 63 init_special_inode(inode, inode->i_mode, inode->i_rdev); 64 } 65 } 66 67 /* 68 * Workhorse of both fsync & write_inode 69 */ 70 int jfs_commit_inode(struct inode *inode, int wait) 71 { 72 int rc = 0; 73 tid_t tid; 74 static int noisy = 5; 75 76 jfs_info("In jfs_commit_inode, inode = 0x%p", inode); 77 78 /* 79 * Don't commit if inode has been committed since last being 80 * marked dirty, or if it has been deleted. 81 */ 82 if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode)) 83 return 0; 84 85 if (isReadOnly(inode)) { 86 /* kernel allows writes to devices on read-only 87 * partitions and may think inode is dirty 88 */ 89 if (!special_file(inode->i_mode) && noisy) { 90 jfs_err("jfs_commit_inode(0x%p) called on " 91 "read-only volume", inode); 92 jfs_err("Is remount racy?"); 93 noisy--; 94 } 95 return 0; 96 } 97 98 tid = txBegin(inode->i_sb, COMMIT_INODE); 99 down(&JFS_IP(inode)->commit_sem); 100 101 /* 102 * Retest inode state after taking commit_sem 103 */ 104 if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode)) 105 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0); 106 107 txEnd(tid); 108 up(&JFS_IP(inode)->commit_sem); 109 return rc; 110 } 111 112 int jfs_write_inode(struct inode *inode, int wait) 113 { 114 if (test_cflag(COMMIT_Nolink, inode)) 115 return 0; 116 /* 117 * If COMMIT_DIRTY is not set, the inode isn't really dirty. 118 * It has been committed since the last change, but was still 119 * on the dirty inode list. 120 */ 121 if (!test_cflag(COMMIT_Dirty, inode)) { 122 /* Make sure committed changes hit the disk */ 123 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait); 124 return 0; 125 } 126 127 if (jfs_commit_inode(inode, wait)) { 128 jfs_err("jfs_write_inode: jfs_commit_inode failed!"); 129 return -EIO; 130 } else 131 return 0; 132 } 133 134 void jfs_delete_inode(struct inode *inode) 135 { 136 jfs_info("In jfs_delete_inode, inode = 0x%p", inode); 137 138 if (test_cflag(COMMIT_Freewmap, inode)) 139 freeZeroLink(inode); 140 141 diFree(inode); 142 143 /* 144 * Free the inode from the quota allocation. 145 */ 146 DQUOT_INIT(inode); 147 DQUOT_FREE_INODE(inode); 148 DQUOT_DROP(inode); 149 150 clear_inode(inode); 151 } 152 153 void jfs_dirty_inode(struct inode *inode) 154 { 155 static int noisy = 5; 156 157 if (isReadOnly(inode)) { 158 if (!special_file(inode->i_mode) && noisy) { 159 /* kernel allows writes to devices on read-only 160 * partitions and may try to mark inode dirty 161 */ 162 jfs_err("jfs_dirty_inode called on read-only volume"); 163 jfs_err("Is remount racy?"); 164 noisy--; 165 } 166 return; 167 } 168 169 set_cflag(COMMIT_Dirty, inode); 170 } 171 172 static int 173 jfs_get_blocks(struct inode *ip, sector_t lblock, unsigned long max_blocks, 174 struct buffer_head *bh_result, int create) 175 { 176 s64 lblock64 = lblock; 177 int rc = 0; 178 int take_locks; 179 xad_t xad; 180 s64 xaddr; 181 int xflag; 182 s32 xlen; 183 184 /* 185 * If this is a special inode (imap, dmap) 186 * the lock should already be taken 187 */ 188 take_locks = (JFS_IP(ip)->fileset != AGGREGATE_I); 189 190 /* 191 * Take appropriate lock on inode 192 */ 193 if (take_locks) { 194 if (create) 195 IWRITE_LOCK(ip); 196 else 197 IREAD_LOCK(ip); 198 } 199 200 if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) && 201 (xtLookup(ip, lblock64, max_blocks, &xflag, &xaddr, &xlen, 0) 202 == 0) && xlen) { 203 if (xflag & XAD_NOTRECORDED) { 204 if (!create) 205 /* 206 * Allocated but not recorded, read treats 207 * this as a hole 208 */ 209 goto unlock; 210 #ifdef _JFS_4K 211 XADoffset(&xad, lblock64); 212 XADlength(&xad, xlen); 213 XADaddress(&xad, xaddr); 214 #else /* _JFS_4K */ 215 /* 216 * As long as block size = 4K, this isn't a problem. 217 * We should mark the whole page not ABNR, but how 218 * will we know to mark the other blocks BH_New? 219 */ 220 BUG(); 221 #endif /* _JFS_4K */ 222 rc = extRecord(ip, &xad); 223 if (rc) 224 goto unlock; 225 set_buffer_new(bh_result); 226 } 227 228 map_bh(bh_result, ip->i_sb, xaddr); 229 bh_result->b_size = xlen << ip->i_blkbits; 230 goto unlock; 231 } 232 if (!create) 233 goto unlock; 234 235 /* 236 * Allocate a new block 237 */ 238 #ifdef _JFS_4K 239 if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad))) 240 goto unlock; 241 rc = extAlloc(ip, max_blocks, lblock64, &xad, FALSE); 242 if (rc) 243 goto unlock; 244 245 set_buffer_new(bh_result); 246 map_bh(bh_result, ip->i_sb, addressXAD(&xad)); 247 bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits; 248 249 #else /* _JFS_4K */ 250 /* 251 * We need to do whatever it takes to keep all but the last buffers 252 * in 4K pages - see jfs_write.c 253 */ 254 BUG(); 255 #endif /* _JFS_4K */ 256 257 unlock: 258 /* 259 * Release lock on inode 260 */ 261 if (take_locks) { 262 if (create) 263 IWRITE_UNLOCK(ip); 264 else 265 IREAD_UNLOCK(ip); 266 } 267 return rc; 268 } 269 270 static int jfs_get_block(struct inode *ip, sector_t lblock, 271 struct buffer_head *bh_result, int create) 272 { 273 return jfs_get_blocks(ip, lblock, 1, bh_result, create); 274 } 275 276 static int jfs_writepage(struct page *page, struct writeback_control *wbc) 277 { 278 return nobh_writepage(page, jfs_get_block, wbc); 279 } 280 281 static int jfs_writepages(struct address_space *mapping, 282 struct writeback_control *wbc) 283 { 284 return mpage_writepages(mapping, wbc, jfs_get_block); 285 } 286 287 static int jfs_readpage(struct file *file, struct page *page) 288 { 289 return mpage_readpage(page, jfs_get_block); 290 } 291 292 static int jfs_readpages(struct file *file, struct address_space *mapping, 293 struct list_head *pages, unsigned nr_pages) 294 { 295 return mpage_readpages(mapping, pages, nr_pages, jfs_get_block); 296 } 297 298 static int jfs_prepare_write(struct file *file, 299 struct page *page, unsigned from, unsigned to) 300 { 301 return nobh_prepare_write(page, from, to, 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_blocks, NULL); 317 } 318 319 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 .prepare_write = jfs_prepare_write, 326 .commit_write = nobh_commit_write, 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_sem 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 down(&JFS_IP(ip)->commit_sem); 357 358 newsize = xtTruncate(tid, ip, length, 359 COMMIT_TRUNCATE | COMMIT_PWMAP); 360 if (newsize < 0) { 361 txEnd(tid); 362 up(&JFS_IP(ip)->commit_sem); 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 up(&JFS_IP(ip)->commit_sem); 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); 380 381 IWRITE_LOCK(ip); 382 jfs_truncate_nolock(ip, ip->i_size); 383 IWRITE_UNLOCK(ip); 384 } 385