|  | /* | 
|  | *  linux/fs/sysv/inode.c | 
|  | * | 
|  | *  minix/inode.c | 
|  | *  Copyright (C) 1991, 1992  Linus Torvalds | 
|  | * | 
|  | *  xenix/inode.c | 
|  | *  Copyright (C) 1992  Doug Evans | 
|  | * | 
|  | *  coh/inode.c | 
|  | *  Copyright (C) 1993  Pascal Haible, Bruno Haible | 
|  | * | 
|  | *  sysv/inode.c | 
|  | *  Copyright (C) 1993  Paul B. Monday | 
|  | * | 
|  | *  sysv/inode.c | 
|  | *  Copyright (C) 1993  Bruno Haible | 
|  | *  Copyright (C) 1997, 1998  Krzysztof G. Baranowski | 
|  | * | 
|  | *  This file contains code for allocating/freeing inodes and for read/writing | 
|  | *  the superblock. | 
|  | */ | 
|  |  | 
|  | #include <linux/highuid.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/buffer_head.h> | 
|  | #include <linux/vfs.h> | 
|  | #include <linux/writeback.h> | 
|  | #include <linux/namei.h> | 
|  | #include <asm/byteorder.h> | 
|  | #include "sysv.h" | 
|  |  | 
|  | static int sysv_sync_fs(struct super_block *sb, int wait) | 
|  | { | 
|  | struct sysv_sb_info *sbi = SYSV_SB(sb); | 
|  | unsigned long time = get_seconds(), old_time; | 
|  |  | 
|  | mutex_lock(&sbi->s_lock); | 
|  |  | 
|  | /* | 
|  | * If we are going to write out the super block, | 
|  | * then attach current time stamp. | 
|  | * But if the filesystem was marked clean, keep it clean. | 
|  | */ | 
|  | old_time = fs32_to_cpu(sbi, *sbi->s_sb_time); | 
|  | if (sbi->s_type == FSTYPE_SYSV4) { | 
|  | if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time)) | 
|  | *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time); | 
|  | *sbi->s_sb_time = cpu_to_fs32(sbi, time); | 
|  | mark_buffer_dirty(sbi->s_bh2); | 
|  | } | 
|  |  | 
|  | mutex_unlock(&sbi->s_lock); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int sysv_remount(struct super_block *sb, int *flags, char *data) | 
|  | { | 
|  | struct sysv_sb_info *sbi = SYSV_SB(sb); | 
|  |  | 
|  | sync_filesystem(sb); | 
|  | if (sbi->s_forced_ro) | 
|  | *flags |= MS_RDONLY; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void sysv_put_super(struct super_block *sb) | 
|  | { | 
|  | struct sysv_sb_info *sbi = SYSV_SB(sb); | 
|  |  | 
|  | if (!(sb->s_flags & MS_RDONLY)) { | 
|  | /* XXX ext2 also updates the state here */ | 
|  | mark_buffer_dirty(sbi->s_bh1); | 
|  | if (sbi->s_bh1 != sbi->s_bh2) | 
|  | mark_buffer_dirty(sbi->s_bh2); | 
|  | } | 
|  |  | 
|  | brelse(sbi->s_bh1); | 
|  | if (sbi->s_bh1 != sbi->s_bh2) | 
|  | brelse(sbi->s_bh2); | 
|  |  | 
|  | kfree(sbi); | 
|  | } | 
|  |  | 
|  | static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf) | 
|  | { | 
|  | struct super_block *sb = dentry->d_sb; | 
|  | struct sysv_sb_info *sbi = SYSV_SB(sb); | 
|  | u64 id = huge_encode_dev(sb->s_bdev->bd_dev); | 
|  |  | 
|  | buf->f_type = sb->s_magic; | 
|  | buf->f_bsize = sb->s_blocksize; | 
|  | buf->f_blocks = sbi->s_ndatazones; | 
|  | buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); | 
|  | buf->f_files = sbi->s_ninodes; | 
|  | buf->f_ffree = sysv_count_free_inodes(sb); | 
|  | buf->f_namelen = SYSV_NAMELEN; | 
|  | buf->f_fsid.val[0] = (u32)id; | 
|  | buf->f_fsid.val[1] = (u32)(id >> 32); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 | 
|  | */ | 
|  | static inline void read3byte(struct sysv_sb_info *sbi, | 
|  | unsigned char * from, unsigned char * to) | 
|  | { | 
|  | if (sbi->s_bytesex == BYTESEX_PDP) { | 
|  | to[0] = from[0]; | 
|  | to[1] = 0; | 
|  | to[2] = from[1]; | 
|  | to[3] = from[2]; | 
|  | } else if (sbi->s_bytesex == BYTESEX_LE) { | 
|  | to[0] = from[0]; | 
|  | to[1] = from[1]; | 
|  | to[2] = from[2]; | 
|  | to[3] = 0; | 
|  | } else { | 
|  | to[0] = 0; | 
|  | to[1] = from[0]; | 
|  | to[2] = from[1]; | 
|  | to[3] = from[2]; | 
|  | } | 
|  | } | 
|  |  | 
|  | static inline void write3byte(struct sysv_sb_info *sbi, | 
|  | unsigned char * from, unsigned char * to) | 
|  | { | 
|  | if (sbi->s_bytesex == BYTESEX_PDP) { | 
|  | to[0] = from[0]; | 
|  | to[1] = from[2]; | 
|  | to[2] = from[3]; | 
|  | } else if (sbi->s_bytesex == BYTESEX_LE) { | 
|  | to[0] = from[0]; | 
|  | to[1] = from[1]; | 
|  | to[2] = from[2]; | 
|  | } else { | 
|  | to[0] = from[1]; | 
|  | to[1] = from[2]; | 
|  | to[2] = from[3]; | 
|  | } | 
|  | } | 
|  |  | 
|  | static const struct inode_operations sysv_symlink_inode_operations = { | 
|  | .readlink	= generic_readlink, | 
|  | .follow_link	= page_follow_link_light, | 
|  | .put_link	= page_put_link, | 
|  | .getattr	= sysv_getattr, | 
|  | }; | 
|  |  | 
|  | void sysv_set_inode(struct inode *inode, dev_t rdev) | 
|  | { | 
|  | if (S_ISREG(inode->i_mode)) { | 
|  | inode->i_op = &sysv_file_inode_operations; | 
|  | inode->i_fop = &sysv_file_operations; | 
|  | inode->i_mapping->a_ops = &sysv_aops; | 
|  | } else if (S_ISDIR(inode->i_mode)) { | 
|  | inode->i_op = &sysv_dir_inode_operations; | 
|  | inode->i_fop = &sysv_dir_operations; | 
|  | inode->i_mapping->a_ops = &sysv_aops; | 
|  | } else if (S_ISLNK(inode->i_mode)) { | 
|  | if (inode->i_blocks) { | 
|  | inode->i_op = &sysv_symlink_inode_operations; | 
|  | inode->i_mapping->a_ops = &sysv_aops; | 
|  | } else { | 
|  | inode->i_op = &sysv_fast_symlink_inode_operations; | 
|  | nd_terminate_link(SYSV_I(inode)->i_data, inode->i_size, | 
|  | sizeof(SYSV_I(inode)->i_data) - 1); | 
|  | } | 
|  | } else | 
|  | init_special_inode(inode, inode->i_mode, rdev); | 
|  | } | 
|  |  | 
|  | struct inode *sysv_iget(struct super_block *sb, unsigned int ino) | 
|  | { | 
|  | struct sysv_sb_info * sbi = SYSV_SB(sb); | 
|  | struct buffer_head * bh; | 
|  | struct sysv_inode * raw_inode; | 
|  | struct sysv_inode_info * si; | 
|  | struct inode *inode; | 
|  | unsigned int block; | 
|  |  | 
|  | if (!ino || ino > sbi->s_ninodes) { | 
|  | printk("Bad inode number on dev %s: %d is out of range\n", | 
|  | sb->s_id, ino); | 
|  | return ERR_PTR(-EIO); | 
|  | } | 
|  |  | 
|  | inode = iget_locked(sb, ino); | 
|  | if (!inode) | 
|  | return ERR_PTR(-ENOMEM); | 
|  | if (!(inode->i_state & I_NEW)) | 
|  | return inode; | 
|  |  | 
|  | raw_inode = sysv_raw_inode(sb, ino, &bh); | 
|  | if (!raw_inode) { | 
|  | printk("Major problem: unable to read inode from dev %s\n", | 
|  | inode->i_sb->s_id); | 
|  | goto bad_inode; | 
|  | } | 
|  | /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ | 
|  | inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); | 
|  | i_uid_write(inode, (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid)); | 
|  | i_gid_write(inode, (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid)); | 
|  | set_nlink(inode, fs16_to_cpu(sbi, raw_inode->i_nlink)); | 
|  | inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); | 
|  | inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); | 
|  | inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); | 
|  | inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_ctime); | 
|  | inode->i_ctime.tv_nsec = 0; | 
|  | inode->i_atime.tv_nsec = 0; | 
|  | inode->i_mtime.tv_nsec = 0; | 
|  | inode->i_blocks = 0; | 
|  |  | 
|  | si = SYSV_I(inode); | 
|  | for (block = 0; block < 10+1+1+1; block++) | 
|  | read3byte(sbi, &raw_inode->i_data[3*block], | 
|  | (u8 *)&si->i_data[block]); | 
|  | brelse(bh); | 
|  | si->i_dir_start_lookup = 0; | 
|  | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) | 
|  | sysv_set_inode(inode, | 
|  | old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); | 
|  | else | 
|  | sysv_set_inode(inode, 0); | 
|  | unlock_new_inode(inode); | 
|  | return inode; | 
|  |  | 
|  | bad_inode: | 
|  | iget_failed(inode); | 
|  | return ERR_PTR(-EIO); | 
|  | } | 
|  |  | 
|  | static int __sysv_write_inode(struct inode *inode, int wait) | 
|  | { | 
|  | struct super_block * sb = inode->i_sb; | 
|  | struct sysv_sb_info * sbi = SYSV_SB(sb); | 
|  | struct buffer_head * bh; | 
|  | struct sysv_inode * raw_inode; | 
|  | struct sysv_inode_info * si; | 
|  | unsigned int ino, block; | 
|  | int err = 0; | 
|  |  | 
|  | ino = inode->i_ino; | 
|  | if (!ino || ino > sbi->s_ninodes) { | 
|  | printk("Bad inode number on dev %s: %d is out of range\n", | 
|  | inode->i_sb->s_id, ino); | 
|  | return -EIO; | 
|  | } | 
|  | raw_inode = sysv_raw_inode(sb, ino, &bh); | 
|  | if (!raw_inode) { | 
|  | printk("unable to read i-node block\n"); | 
|  | return -EIO; | 
|  | } | 
|  |  | 
|  | raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); | 
|  | raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(i_uid_read(inode))); | 
|  | raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(i_gid_read(inode))); | 
|  | raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); | 
|  | raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); | 
|  | raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); | 
|  | raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); | 
|  | raw_inode->i_ctime = cpu_to_fs32(sbi, inode->i_ctime.tv_sec); | 
|  |  | 
|  | si = SYSV_I(inode); | 
|  | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) | 
|  | si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); | 
|  | for (block = 0; block < 10+1+1+1; block++) | 
|  | write3byte(sbi, (u8 *)&si->i_data[block], | 
|  | &raw_inode->i_data[3*block]); | 
|  | mark_buffer_dirty(bh); | 
|  | if (wait) { | 
|  | sync_dirty_buffer(bh); | 
|  | if (buffer_req(bh) && !buffer_uptodate(bh)) { | 
|  | printk ("IO error syncing sysv inode [%s:%08x]\n", | 
|  | sb->s_id, ino); | 
|  | err = -EIO; | 
|  | } | 
|  | } | 
|  | brelse(bh); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | int sysv_write_inode(struct inode *inode, struct writeback_control *wbc) | 
|  | { | 
|  | return __sysv_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); | 
|  | } | 
|  |  | 
|  | int sysv_sync_inode(struct inode *inode) | 
|  | { | 
|  | return __sysv_write_inode(inode, 1); | 
|  | } | 
|  |  | 
|  | static void sysv_evict_inode(struct inode *inode) | 
|  | { | 
|  | truncate_inode_pages_final(&inode->i_data); | 
|  | if (!inode->i_nlink) { | 
|  | inode->i_size = 0; | 
|  | sysv_truncate(inode); | 
|  | } | 
|  | invalidate_inode_buffers(inode); | 
|  | clear_inode(inode); | 
|  | if (!inode->i_nlink) | 
|  | sysv_free_inode(inode); | 
|  | } | 
|  |  | 
|  | static struct kmem_cache *sysv_inode_cachep; | 
|  |  | 
|  | static struct inode *sysv_alloc_inode(struct super_block *sb) | 
|  | { | 
|  | struct sysv_inode_info *si; | 
|  |  | 
|  | si = kmem_cache_alloc(sysv_inode_cachep, GFP_KERNEL); | 
|  | if (!si) | 
|  | return NULL; | 
|  | return &si->vfs_inode; | 
|  | } | 
|  |  | 
|  | static void sysv_i_callback(struct rcu_head *head) | 
|  | { | 
|  | struct inode *inode = container_of(head, struct inode, i_rcu); | 
|  | kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); | 
|  | } | 
|  |  | 
|  | static void sysv_destroy_inode(struct inode *inode) | 
|  | { | 
|  | call_rcu(&inode->i_rcu, sysv_i_callback); | 
|  | } | 
|  |  | 
|  | static void init_once(void *p) | 
|  | { | 
|  | struct sysv_inode_info *si = (struct sysv_inode_info *)p; | 
|  |  | 
|  | inode_init_once(&si->vfs_inode); | 
|  | } | 
|  |  | 
|  | const struct super_operations sysv_sops = { | 
|  | .alloc_inode	= sysv_alloc_inode, | 
|  | .destroy_inode	= sysv_destroy_inode, | 
|  | .write_inode	= sysv_write_inode, | 
|  | .evict_inode	= sysv_evict_inode, | 
|  | .put_super	= sysv_put_super, | 
|  | .sync_fs	= sysv_sync_fs, | 
|  | .remount_fs	= sysv_remount, | 
|  | .statfs		= sysv_statfs, | 
|  | }; | 
|  |  | 
|  | int __init sysv_init_icache(void) | 
|  | { | 
|  | sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", | 
|  | sizeof(struct sysv_inode_info), 0, | 
|  | SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, | 
|  | init_once); | 
|  | if (!sysv_inode_cachep) | 
|  | return -ENOMEM; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void sysv_destroy_icache(void) | 
|  | { | 
|  | /* | 
|  | * Make sure all delayed rcu free inodes are flushed before we | 
|  | * destroy cache. | 
|  | */ | 
|  | rcu_barrier(); | 
|  | kmem_cache_destroy(sysv_inode_cachep); | 
|  | } |