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1// SPDX-License-Identifier: GPL-2.02/*3 * linux/fs/sysv/inode.c4 *5 * minix/inode.c6 * Copyright (C) 1991, 1992 Linus Torvalds7 *8 * xenix/inode.c9 * Copyright (C) 1992 Doug Evans10 *11 * coh/inode.c12 * Copyright (C) 1993 Pascal Haible, Bruno Haible13 *14 * sysv/inode.c15 * Copyright (C) 1993 Paul B. Monday16 *17 * sysv/inode.c18 * Copyright (C) 1993 Bruno Haible19 * Copyright (C) 1997, 1998 Krzysztof G. Baranowski20 *21 * This file contains code for allocating/freeing inodes and for read/writing22 * 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 be32107 */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 } else167 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_set_atime(inode, fs32_to_cpu(sbi, raw_inode->i_atime), 0);204 inode_set_mtime(inode, fs32_to_cpu(sbi, raw_inode->i_mtime), 0);205 inode_set_ctime(inode, fs32_to_cpu(sbi, raw_inode->i_ctime), 0);206 inode->i_blocks = 0;207 208 si = SYSV_I(inode);209 for (block = 0; block < 10+1+1+1; block++)210 read3byte(sbi, &raw_inode->i_data[3*block],211 (u8 *)&si->i_data[block]);212 brelse(bh);213 si->i_dir_start_lookup = 0;214 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))215 sysv_set_inode(inode,216 old_decode_dev(fs32_to_cpu(sbi, si->i_data[0])));217 else218 sysv_set_inode(inode, 0);219 unlock_new_inode(inode);220 return inode;221 222bad_inode:223 iget_failed(inode);224 return ERR_PTR(-EIO);225}226 227static int __sysv_write_inode(struct inode *inode, int wait)228{229 struct super_block * sb = inode->i_sb;230 struct sysv_sb_info * sbi = SYSV_SB(sb);231 struct buffer_head * bh;232 struct sysv_inode * raw_inode;233 struct sysv_inode_info * si;234 unsigned int ino, block;235 int err = 0;236 237 ino = inode->i_ino;238 if (!ino || ino > sbi->s_ninodes) {239 printk("Bad inode number on dev %s: %d is out of range\n",240 inode->i_sb->s_id, ino);241 return -EIO;242 }243 raw_inode = sysv_raw_inode(sb, ino, &bh);244 if (!raw_inode) {245 printk("unable to read i-node block\n");246 return -EIO;247 }248 249 raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode);250 raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(i_uid_read(inode)));251 raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(i_gid_read(inode)));252 raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink);253 raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size);254 raw_inode->i_atime = cpu_to_fs32(sbi, inode_get_atime_sec(inode));255 raw_inode->i_mtime = cpu_to_fs32(sbi, inode_get_mtime_sec(inode));256 raw_inode->i_ctime = cpu_to_fs32(sbi, inode_get_ctime_sec(inode));257 258 si = SYSV_I(inode);259 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))260 si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev));261 for (block = 0; block < 10+1+1+1; block++)262 write3byte(sbi, (u8 *)&si->i_data[block],263 &raw_inode->i_data[3*block]);264 mark_buffer_dirty(bh);265 if (wait) {266 sync_dirty_buffer(bh);267 if (buffer_req(bh) && !buffer_uptodate(bh)) {268 printk ("IO error syncing sysv inode [%s:%08x]\n",269 sb->s_id, ino);270 err = -EIO;271 }272 }273 brelse(bh);274 return err;275}276 277int sysv_write_inode(struct inode *inode, struct writeback_control *wbc)278{279 return __sysv_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);280}281 282int sysv_sync_inode(struct inode *inode)283{284 return __sysv_write_inode(inode, 1);285}286 287static void sysv_evict_inode(struct inode *inode)288{289 truncate_inode_pages_final(&inode->i_data);290 if (!inode->i_nlink) {291 inode->i_size = 0;292 sysv_truncate(inode);293 }294 invalidate_inode_buffers(inode);295 clear_inode(inode);296 if (!inode->i_nlink)297 sysv_free_inode(inode);298}299 300static struct kmem_cache *sysv_inode_cachep;301 302static struct inode *sysv_alloc_inode(struct super_block *sb)303{304 struct sysv_inode_info *si;305 306 si = alloc_inode_sb(sb, sysv_inode_cachep, GFP_KERNEL);307 if (!si)308 return NULL;309 return &si->vfs_inode;310}311 312static void sysv_free_in_core_inode(struct inode *inode)313{314 kmem_cache_free(sysv_inode_cachep, SYSV_I(inode));315}316 317static void init_once(void *p)318{319 struct sysv_inode_info *si = (struct sysv_inode_info *)p;320 321 inode_init_once(&si->vfs_inode);322}323 324const struct super_operations sysv_sops = {325 .alloc_inode = sysv_alloc_inode,326 .free_inode = sysv_free_in_core_inode,327 .write_inode = sysv_write_inode,328 .evict_inode = sysv_evict_inode,329 .put_super = sysv_put_super,330 .sync_fs = sysv_sync_fs,331 .remount_fs = sysv_remount,332 .statfs = sysv_statfs,333};334 335int __init sysv_init_icache(void)336{337 sysv_inode_cachep = kmem_cache_create("sysv_inode_cache",338 sizeof(struct sysv_inode_info), 0,339 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT,340 init_once);341 if (!sysv_inode_cachep)342 return -ENOMEM;343 return 0;344}345 346void sysv_destroy_icache(void)347{348 /*349 * Make sure all delayed rcu free inodes are flushed before we350 * destroy cache.351 */352 rcu_barrier();353 kmem_cache_destroy(sysv_inode_cachep);354}355