1// SPDX-License-Identifier: GPL-2.0 2/* 3 * linux/fs/sysv/inode.c 4 * 5 * minix/inode.c 6 * Copyright (C) 1991, 1992 Linus Torvalds 7 * 8 * xenix/inode.c 9 * Copyright (C) 1992 Doug Evans 10 * 11 * coh/inode.c 12 * Copyright (C) 1993 Pascal Haible, Bruno Haible 13 * 14 * sysv/inode.c 15 * Copyright (C) 1993 Paul B. Monday 16 * 17 * sysv/inode.c 18 * Copyright (C) 1993 Bruno Haible 19 * Copyright (C) 1997, 1998 Krzysztof G. Baranowski 20 * 21 * This file contains code for allocating/freeing inodes and for read/writing 22 * the superblock. 23 */ 24 25#include <linux/highuid.h> 26#include <linux/slab.h> 27#include <linux/init.h> 28#include <linux/buffer_head.h> 29#include <linux/vfs.h> 30#include <linux/writeback.h> 31#include <linux/namei.h> 32#include <asm/byteorder.h> 33#include "sysv.h" 34 35static int sysv_sync_fs(struct super_block *sb, int wait) 36{ 37 struct sysv_sb_info *sbi = SYSV_SB(sb); 38 u32 time = (u32)ktime_get_real_seconds(), old_time; 39 40 mutex_lock(&sbi->s_lock); 41 42 /* 43 * If we are going to write out the super block, 44 * then attach current time stamp. 45 * But if the filesystem was marked clean, keep it clean. 46 */ 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, 0x7c269d38u - old_time)) 50 *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38u - time); 51 *sbi->s_sb_time = cpu_to_fs32(sbi, time); 52 mark_buffer_dirty(sbi->s_bh2); 53 } 54 55 mutex_unlock(&sbi->s_lock); 56 57 return 0; 58} 59 60static int sysv_remount(struct super_block *sb, int *flags, char *data) 61{ 62 struct sysv_sb_info *sbi = SYSV_SB(sb); 63 64 sync_filesystem(sb); 65 if (sbi->s_forced_ro) 66 *flags |= SB_RDONLY; 67 return 0; 68} 69 70static void sysv_put_super(struct super_block *sb) 71{ 72 struct sysv_sb_info *sbi = SYSV_SB(sb); 73 74 if (!sb_rdonly(sb)) { 75 /* XXX ext2 also updates the state here */ 76 mark_buffer_dirty(sbi->s_bh1); 77 if (sbi->s_bh1 != sbi->s_bh2) 78 mark_buffer_dirty(sbi->s_bh2); 79 } 80 81 brelse(sbi->s_bh1); 82 if (sbi->s_bh1 != sbi->s_bh2) 83 brelse(sbi->s_bh2); 84 85 kfree(sbi); 86} 87 88static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf) 89{ 90 struct super_block *sb = dentry->d_sb; 91 struct sysv_sb_info *sbi = SYSV_SB(sb); 92 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 93 94 buf->f_type = sb->s_magic; 95 buf->f_bsize = sb->s_blocksize; 96 buf->f_blocks = sbi->s_ndatazones; 97 buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); 98 buf->f_files = sbi->s_ninodes; 99 buf->f_ffree = sysv_count_free_inodes(sb); 100 buf->f_namelen = SYSV_NAMELEN; 101 buf->f_fsid = u64_to_fsid(id); 102 return 0; 103} 104 105/* 106 * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 107 */ 108static inline void read3byte(struct sysv_sb_info *sbi, 109 unsigned char * from, unsigned char * to) 110{ 111 if (sbi->s_bytesex == BYTESEX_PDP) { 112 to[0] = from[0]; 113 to[1] = 0; 114 to[2] = from[1]; 115 to[3] = from[2]; 116 } else if (sbi->s_bytesex == BYTESEX_LE) { 117 to[0] = from[0]; 118 to[1] = from[1]; 119 to[2] = from[2]; 120 to[3] = 0; 121 } else { 122 to[0] = 0; 123 to[1] = from[0]; 124 to[2] = from[1]; 125 to[3] = from[2]; 126 } 127} 128 129static inline void write3byte(struct sysv_sb_info *sbi, 130 unsigned char * from, unsigned char * to) 131{ 132 if (sbi->s_bytesex == BYTESEX_PDP) { 133 to[0] = from[0]; 134 to[1] = from[2]; 135 to[2] = from[3]; 136 } else if (sbi->s_bytesex == BYTESEX_LE) { 137 to[0] = from[0]; 138 to[1] = from[1]; 139 to[2] = from[2]; 140 } else { 141 to[0] = from[1]; 142 to[1] = from[2]; 143 to[2] = from[3]; 144 } 145} 146 147static const struct inode_operations sysv_symlink_inode_operations = { 148 .get_link = page_get_link, 149 .getattr = sysv_getattr, 150}; 151 152void sysv_set_inode(struct inode *inode, dev_t rdev) 153{ 154 if (S_ISREG(inode->i_mode)) { 155 inode->i_op = &sysv_file_inode_operations; 156 inode->i_fop = &sysv_file_operations; 157 inode->i_mapping->a_ops = &sysv_aops; 158 } else if (S_ISDIR(inode->i_mode)) { 159 inode->i_op = &sysv_dir_inode_operations; 160 inode->i_fop = &sysv_dir_operations; 161 inode->i_mapping->a_ops = &sysv_aops; 162 } else if (S_ISLNK(inode->i_mode)) { 163 inode->i_op = &sysv_symlink_inode_operations; 164 inode_nohighmem(inode); 165 inode->i_mapping->a_ops = &sysv_aops; 166 } else 167 init_special_inode(inode, inode->i_mode, rdev); 168} 169 170struct inode *sysv_iget(struct super_block *sb, unsigned int ino) 171{ 172 struct sysv_sb_info * sbi = SYSV_SB(sb); 173 struct buffer_head * bh; 174 struct sysv_inode * raw_inode; 175 struct sysv_inode_info * si; 176 struct inode *inode; 177 unsigned int block; 178 179 if (!ino || ino > sbi->s_ninodes) { 180 printk("Bad inode number on dev %s: %d is out of range\n", 181 sb->s_id, ino); 182 return ERR_PTR(-EIO); 183 } 184 185 inode = iget_locked(sb, ino); 186 if (!inode) 187 return ERR_PTR(-ENOMEM); 188 if (!(inode->i_state & I_NEW)) 189 return inode; 190 191 raw_inode = sysv_raw_inode(sb, ino, &bh); 192 if (!raw_inode) { 193 printk("Major problem: unable to read inode from dev %s\n", 194 inode->i_sb->s_id); 195 goto bad_inode; 196 } 197 /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ 198 inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); 199 i_uid_write(inode, (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid)); 200 i_gid_write(inode, (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid)); 201 set_nlink(inode, fs16_to_cpu(sbi, raw_inode->i_nlink)); 202 inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); 203 inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); 204 inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); 205 inode_set_ctime(inode, fs32_to_cpu(sbi, raw_inode->i_ctime), 0); 206 inode->i_atime.tv_nsec = 0; 207 inode->i_mtime.tv_nsec = 0; 208 inode->i_blocks = 0; 209 210 si = SYSV_I(inode); 211 for (block = 0; block < 10+1+1+1; block++) 212 read3byte(sbi, &raw_inode->i_data[3*block], 213 (u8 *)&si->i_data[block]); 214 brelse(bh); 215 si->i_dir_start_lookup = 0; 216 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 217 sysv_set_inode(inode, 218 old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); 219 else 220 sysv_set_inode(inode, 0); 221 unlock_new_inode(inode); 222 return inode; 223 224bad_inode: 225 iget_failed(inode); 226 return ERR_PTR(-EIO); 227} 228 229static int __sysv_write_inode(struct inode *inode, int wait) 230{ 231 struct super_block * sb = inode->i_sb; 232 struct sysv_sb_info * sbi = SYSV_SB(sb); 233 struct buffer_head * bh; 234 struct sysv_inode * raw_inode; 235 struct sysv_inode_info * si; 236 unsigned int ino, block; 237 int err = 0; 238 239 ino = inode->i_ino; 240 if (!ino || ino > sbi->s_ninodes) { 241 printk("Bad inode number on dev %s: %d is out of range\n", 242 inode->i_sb->s_id, ino); 243 return -EIO; 244 } 245 raw_inode = sysv_raw_inode(sb, ino, &bh); 246 if (!raw_inode) { 247 printk("unable to read i-node block\n"); 248 return -EIO; 249 } 250 251 raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); 252 raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(i_uid_read(inode))); 253 raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(i_gid_read(inode))); 254 raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); 255 raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); 256 raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); 257 raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); 258 raw_inode->i_ctime = cpu_to_fs32(sbi, inode_get_ctime(inode).tv_sec); 259 260 si = SYSV_I(inode); 261 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 262 si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); 263 for (block = 0; block < 10+1+1+1; block++) 264 write3byte(sbi, (u8 *)&si->i_data[block], 265 &raw_inode->i_data[3*block]); 266 mark_buffer_dirty(bh); 267 if (wait) { 268 sync_dirty_buffer(bh); 269 if (buffer_req(bh) && !buffer_uptodate(bh)) { 270 printk ("IO error syncing sysv inode [%s:%08x]\n", 271 sb->s_id, ino); 272 err = -EIO; 273 } 274 } 275 brelse(bh); 276 return err; 277} 278 279int sysv_write_inode(struct inode *inode, struct writeback_control *wbc) 280{ 281 return __sysv_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); 282} 283 284int sysv_sync_inode(struct inode *inode) 285{ 286 return __sysv_write_inode(inode, 1); 287} 288 289static void sysv_evict_inode(struct inode *inode) 290{ 291 truncate_inode_pages_final(&inode->i_data); 292 if (!inode->i_nlink) { 293 inode->i_size = 0; 294 sysv_truncate(inode); 295 } 296 invalidate_inode_buffers(inode); 297 clear_inode(inode); 298 if (!inode->i_nlink) 299 sysv_free_inode(inode); 300} 301 302static struct kmem_cache *sysv_inode_cachep; 303 304static struct inode *sysv_alloc_inode(struct super_block *sb) 305{ 306 struct sysv_inode_info *si; 307 308 si = alloc_inode_sb(sb, sysv_inode_cachep, GFP_KERNEL); 309 if (!si) 310 return NULL; 311 return &si->vfs_inode; 312} 313 314static void sysv_free_in_core_inode(struct inode *inode) 315{ 316 kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); 317} 318 319static void init_once(void *p) 320{ 321 struct sysv_inode_info *si = (struct sysv_inode_info *)p; 322 323 inode_init_once(&si->vfs_inode); 324} 325 326const struct super_operations sysv_sops = { 327 .alloc_inode = sysv_alloc_inode, 328 .free_inode = sysv_free_in_core_inode, 329 .write_inode = sysv_write_inode, 330 .evict_inode = sysv_evict_inode, 331 .put_super = sysv_put_super, 332 .sync_fs = sysv_sync_fs, 333 .remount_fs = sysv_remount, 334 .statfs = sysv_statfs, 335}; 336 337int __init sysv_init_icache(void) 338{ 339 sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", 340 sizeof(struct sysv_inode_info), 0, 341 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|SLAB_ACCOUNT, 342 init_once); 343 if (!sysv_inode_cachep) 344 return -ENOMEM; 345 return 0; 346} 347 348void sysv_destroy_icache(void) 349{ 350 /* 351 * Make sure all delayed rcu free inodes are flushed before we 352 * destroy cache. 353 */ 354 rcu_barrier(); 355 kmem_cache_destroy(sysv_inode_cachep); 356} 357