1/* 2 * linux/fs/sysv/inode.c 3 * 4 * minix/inode.c 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * xenix/inode.c 8 * Copyright (C) 1992 Doug Evans 9 * 10 * coh/inode.c 11 * Copyright (C) 1993 Pascal Haible, Bruno Haible 12 * 13 * sysv/inode.c 14 * Copyright (C) 1993 Paul B. Monday 15 * 16 * sysv/inode.c 17 * Copyright (C) 1993 Bruno Haible 18 * Copyright (C) 1997, 1998 Krzysztof G. Baranowski 19 * 20 * This file contains code for allocating/freeing inodes and for read/writing 21 * the superblock. 22 */ 23 24#include <linux/highuid.h> 25#include <linux/slab.h> 26#include <linux/init.h> 27#include <linux/buffer_head.h> 28#include <linux/vfs.h> 29#include <linux/writeback.h> 30#include <linux/namei.h> 31#include <asm/byteorder.h> 32#include "sysv.h" 33 34static int sysv_sync_fs(struct super_block *sb, int wait) 35{ 36 struct sysv_sb_info *sbi = SYSV_SB(sb); 37 unsigned long time = get_seconds(), old_time; 38 39 lock_super(sb); 40 41 /* 42 * If we are going to write out the super block, 43 * then attach current time stamp. 44 * But if the filesystem was marked clean, keep it clean. 45 */ 46 sb->s_dirt = 0; 47 old_time = fs32_to_cpu(sbi, *sbi->s_sb_time); 48 if (sbi->s_type == FSTYPE_SYSV4) { 49 if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time)) 50 *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time); 51 *sbi->s_sb_time = cpu_to_fs32(sbi, time); 52 mark_buffer_dirty(sbi->s_bh2); 53 } 54 55 unlock_super(sb); 56 57 return 0; 58} 59 60static void sysv_write_super(struct super_block *sb) 61{ 62 if (!(sb->s_flags & MS_RDONLY)) 63 sysv_sync_fs(sb, 1); 64 else 65 sb->s_dirt = 0; 66} 67 68static int sysv_remount(struct super_block *sb, int *flags, char *data) 69{ 70 struct sysv_sb_info *sbi = SYSV_SB(sb); 71 lock_super(sb); 72 if (sbi->s_forced_ro) 73 *flags |= MS_RDONLY; 74 if (*flags & MS_RDONLY) 75 sysv_write_super(sb); 76 unlock_super(sb); 77 return 0; 78} 79 80static void sysv_put_super(struct super_block *sb) 81{ 82 struct sysv_sb_info *sbi = SYSV_SB(sb); 83 84 if (sb->s_dirt) 85 sysv_write_super(sb); 86 87 if (!(sb->s_flags & MS_RDONLY)) { 88 mark_buffer_dirty(sbi->s_bh1); 89 if (sbi->s_bh1 != sbi->s_bh2) 90 mark_buffer_dirty(sbi->s_bh2); 91 } 92 93 brelse(sbi->s_bh1); 94 if (sbi->s_bh1 != sbi->s_bh2) 95 brelse(sbi->s_bh2); 96 97 kfree(sbi); 98} 99 100static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf) 101{ 102 struct super_block *sb = dentry->d_sb; 103 struct sysv_sb_info *sbi = SYSV_SB(sb); 104 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 105 106 buf->f_type = sb->s_magic; 107 buf->f_bsize = sb->s_blocksize; 108 buf->f_blocks = sbi->s_ndatazones; 109 buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); 110 buf->f_files = sbi->s_ninodes; 111 buf->f_ffree = sysv_count_free_inodes(sb); 112 buf->f_namelen = SYSV_NAMELEN; 113 buf->f_fsid.val[0] = (u32)id; 114 buf->f_fsid.val[1] = (u32)(id >> 32); 115 return 0; 116} 117 118/* 119 * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 120 */ 121static inline void read3byte(struct sysv_sb_info *sbi, 122 unsigned char * from, unsigned char * to) 123{ 124 if (sbi->s_bytesex == BYTESEX_PDP) { 125 to[0] = from[0]; 126 to[1] = 0; 127 to[2] = from[1]; 128 to[3] = from[2]; 129 } else if (sbi->s_bytesex == BYTESEX_LE) { 130 to[0] = from[0]; 131 to[1] = from[1]; 132 to[2] = from[2]; 133 to[3] = 0; 134 } else { 135 to[0] = 0; 136 to[1] = from[0]; 137 to[2] = from[1]; 138 to[3] = from[2]; 139 } 140} 141 142static inline void write3byte(struct sysv_sb_info *sbi, 143 unsigned char * from, unsigned char * to) 144{ 145 if (sbi->s_bytesex == BYTESEX_PDP) { 146 to[0] = from[0]; 147 to[1] = from[2]; 148 to[2] = from[3]; 149 } else if (sbi->s_bytesex == BYTESEX_LE) { 150 to[0] = from[0]; 151 to[1] = from[1]; 152 to[2] = from[2]; 153 } else { 154 to[0] = from[1]; 155 to[1] = from[2]; 156 to[2] = from[3]; 157 } 158} 159 160static const struct inode_operations sysv_symlink_inode_operations = { 161 .readlink = generic_readlink, 162 .follow_link = page_follow_link_light, 163 .put_link = page_put_link, 164 .getattr = sysv_getattr, 165}; 166 167void sysv_set_inode(struct inode *inode, dev_t rdev) 168{ 169 if (S_ISREG(inode->i_mode)) { 170 inode->i_op = &sysv_file_inode_operations; 171 inode->i_fop = &sysv_file_operations; 172 inode->i_mapping->a_ops = &sysv_aops; 173 } else if (S_ISDIR(inode->i_mode)) { 174 inode->i_op = &sysv_dir_inode_operations; 175 inode->i_fop = &sysv_dir_operations; 176 inode->i_mapping->a_ops = &sysv_aops; 177 } else if (S_ISLNK(inode->i_mode)) { 178 if (inode->i_blocks) { 179 inode->i_op = &sysv_symlink_inode_operations; 180 inode->i_mapping->a_ops = &sysv_aops; 181 } else { 182 inode->i_op = &sysv_fast_symlink_inode_operations; 183 nd_terminate_link(SYSV_I(inode)->i_data, inode->i_size, 184 sizeof(SYSV_I(inode)->i_data) - 1); 185 } 186 } else 187 init_special_inode(inode, inode->i_mode, rdev); 188} 189 190struct inode *sysv_iget(struct super_block *sb, unsigned int ino) 191{ 192 struct sysv_sb_info * sbi = SYSV_SB(sb); 193 struct buffer_head * bh; 194 struct sysv_inode * raw_inode; 195 struct sysv_inode_info * si; 196 struct inode *inode; 197 unsigned int block; 198 199 if (!ino || ino > sbi->s_ninodes) { 200 printk("Bad inode number on dev %s: %d is out of range\n", 201 sb->s_id, ino); 202 return ERR_PTR(-EIO); 203 } 204 205 inode = iget_locked(sb, ino); 206 if (!inode) 207 return ERR_PTR(-ENOMEM); 208 if (!(inode->i_state & I_NEW)) 209 return inode; 210 211 raw_inode = sysv_raw_inode(sb, ino, &bh); 212 if (!raw_inode) { 213 printk("Major problem: unable to read inode from dev %s\n", 214 inode->i_sb->s_id); 215 goto bad_inode; 216 } 217 /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ 218 inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); 219 inode->i_uid = (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid); 220 inode->i_gid = (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid); 221 inode->i_nlink = fs16_to_cpu(sbi, raw_inode->i_nlink); 222 inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); 223 inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); 224 inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); 225 inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_ctime); 226 inode->i_ctime.tv_nsec = 0; 227 inode->i_atime.tv_nsec = 0; 228 inode->i_mtime.tv_nsec = 0; 229 inode->i_blocks = 0; 230 231 si = SYSV_I(inode); 232 for (block = 0; block < 10+1+1+1; block++) 233 read3byte(sbi, &raw_inode->i_data[3*block], 234 (u8 *)&si->i_data[block]); 235 brelse(bh); 236 si->i_dir_start_lookup = 0; 237 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 238 sysv_set_inode(inode, 239 old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); 240 else 241 sysv_set_inode(inode, 0); 242 unlock_new_inode(inode); 243 return inode; 244 245bad_inode: 246 iget_failed(inode); 247 return ERR_PTR(-EIO); 248} 249 250static int __sysv_write_inode(struct inode *inode, int wait) 251{ 252 struct super_block * sb = inode->i_sb; 253 struct sysv_sb_info * sbi = SYSV_SB(sb); 254 struct buffer_head * bh; 255 struct sysv_inode * raw_inode; 256 struct sysv_inode_info * si; 257 unsigned int ino, block; 258 int err = 0; 259 260 ino = inode->i_ino; 261 if (!ino || ino > sbi->s_ninodes) { 262 printk("Bad inode number on dev %s: %d is out of range\n", 263 inode->i_sb->s_id, ino); 264 return -EIO; 265 } 266 raw_inode = sysv_raw_inode(sb, ino, &bh); 267 if (!raw_inode) { 268 printk("unable to read i-node block\n"); 269 return -EIO; 270 } 271 272 raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); 273 raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(inode->i_uid)); 274 raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(inode->i_gid)); 275 raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); 276 raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); 277 raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); 278 raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); 279 raw_inode->i_ctime = cpu_to_fs32(sbi, inode->i_ctime.tv_sec); 280 281 si = SYSV_I(inode); 282 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 283 si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); 284 for (block = 0; block < 10+1+1+1; block++) 285 write3byte(sbi, (u8 *)&si->i_data[block], 286 &raw_inode->i_data[3*block]); 287 mark_buffer_dirty(bh); 288 if (wait) { 289 sync_dirty_buffer(bh); 290 if (buffer_req(bh) && !buffer_uptodate(bh)) { 291 printk ("IO error syncing sysv inode [%s:%08x]\n", 292 sb->s_id, ino); 293 err = -EIO; 294 } 295 } 296 brelse(bh); 297 return 0; 298} 299 300int sysv_write_inode(struct inode *inode, struct writeback_control *wbc) 301{ 302 return __sysv_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); 303} 304 305int sysv_sync_inode(struct inode *inode) 306{ 307 return __sysv_write_inode(inode, 1); 308} 309 310static void sysv_evict_inode(struct inode *inode) 311{ 312 truncate_inode_pages(&inode->i_data, 0); 313 if (!inode->i_nlink) { 314 inode->i_size = 0; 315 sysv_truncate(inode); 316 } 317 invalidate_inode_buffers(inode); 318 end_writeback(inode); 319 if (!inode->i_nlink) 320 sysv_free_inode(inode); 321} 322 323static struct kmem_cache *sysv_inode_cachep; 324 325static struct inode *sysv_alloc_inode(struct super_block *sb) 326{ 327 struct sysv_inode_info *si; 328 329 si = kmem_cache_alloc(sysv_inode_cachep, GFP_KERNEL); 330 if (!si) 331 return NULL; 332 return &si->vfs_inode; 333} 334 335static void sysv_destroy_inode(struct inode *inode) 336{ 337 kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); 338} 339 340static void init_once(void *p) 341{ 342 struct sysv_inode_info *si = (struct sysv_inode_info *)p; 343 344 inode_init_once(&si->vfs_inode); 345} 346 347const struct super_operations sysv_sops = { 348 .alloc_inode = sysv_alloc_inode, 349 .destroy_inode = sysv_destroy_inode, 350 .write_inode = sysv_write_inode, 351 .evict_inode = sysv_evict_inode, 352 .put_super = sysv_put_super, 353 .write_super = sysv_write_super, 354 .sync_fs = sysv_sync_fs, 355 .remount_fs = sysv_remount, 356 .statfs = sysv_statfs, 357}; 358 359int __init sysv_init_icache(void) 360{ 361 sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", 362 sizeof(struct sysv_inode_info), 0, 363 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, 364 init_once); 365 if (!sysv_inode_cachep) 366 return -ENOMEM; 367 return 0; 368} 369 370void sysv_destroy_icache(void) 371{ 372 kmem_cache_destroy(sysv_inode_cachep); 373} 374