847 lines
22 KiB
C
847 lines
22 KiB
C
/*
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* Linux/fs/xiafs/namei.c
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*
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* Copyright (C) Q. Frank Xia, 1993.
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*
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* Based on Linus' minix/namei.c
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* Copyright (C) Linus Torvalds, 1991, 1992.
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*
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* This software may be redistributed per Linux Copyright.
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*/
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#include <linux/sched.h>
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#include <linux/xia_fs.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/stat.h>
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#include <linux/fcntl.h>
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#include <linux/errno.h>
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#include <asm/segment.h>
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#include "xiafs_mac.h"
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#define RNDUP4(x) ((3+(u_long)(x)) & ~3)
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/*
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* ok, we cannot use strncmp, as the name is not in our data space.
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* Thus we'll have to use xiafs_match. No big problem. Match also makes
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* some sanity tests.
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*
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* NOTE! unlike strncmp, xiafs_match returns 1 for success, 0 for failure.
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*/
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static int xiafs_match(int len, const char * name, struct xiafs_direct * dep)
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{
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int i;
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if (!dep || !dep->d_ino || len > _XIAFS_NAME_LEN)
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return 0;
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/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
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if (!len && (dep->d_name[0]=='.') && (dep->d_name[1]=='\0'))
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return 1;
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if (len != dep->d_name_len)
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return 0;
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for (i=0; i < len; i++)
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if (*name++ != dep->d_name[i])
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return 0;
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return 1;
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}
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/*
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* xiafs_find_entry()
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*
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* finds an entry in the specified directory with the wanted name. It
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* returns the cache buffer in which the entry was found, and the entry
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* itself (as a parameter - res_dir). It does NOT read the inode of the
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* entry - you'll have to do that yourself if you want to.
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*/
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static struct buffer_head *
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xiafs_find_entry(struct inode * inode, const char * name, int namelen,
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struct xiafs_direct ** res_dir, struct xiafs_direct ** res_pre)
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{
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int i, zones, pos;
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struct buffer_head * bh;
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struct xiafs_direct * dep, * dep_pre;
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*res_dir = NULL;
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if (!inode)
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return NULL;
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if (namelen > _XIAFS_NAME_LEN)
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return NULL;
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if (inode->i_size & (XIAFS_ZSIZE(inode->i_sb) - 1)) {
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printk("XIA-FS: bad dir size (%s %d)\n", WHERE_ERR);
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return NULL;
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}
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zones=inode->i_size >> XIAFS_ZSIZE_BITS(inode->i_sb);
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for (i=0; i < zones; i++ ) {
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bh = xiafs_bread(inode, i, 0);
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if (!bh)
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continue;
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dep_pre=dep=(struct xiafs_direct *)bh->b_data;
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if (!i && (dep->d_rec_len != 12 || !dep->d_ino ||
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dep->d_name_len != 1 || strcmp(dep->d_name, "."))) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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brelse(bh);
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return NULL;
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}
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pos = 0;
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while ( pos < XIAFS_ZSIZE(inode->i_sb) ) {
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if (dep->d_ino > inode->i_sb->u.xiafs_sb.s_ninodes ||
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dep->d_rec_len < 12 ||
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dep->d_rec_len+(char *)dep > bh->b_data+XIAFS_ZSIZE(inode->i_sb) ||
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dep->d_name_len + 8 > dep->d_rec_len || dep->d_name_len <= 0 ||
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dep->d_name[dep->d_name_len] ) {
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brelse(bh);
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return NULL;
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}
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if (xiafs_match(namelen, name, dep)) {
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*res_dir=dep;
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if (res_pre)
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*res_pre=dep_pre;
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return bh;
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}
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pos += dep->d_rec_len;
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dep_pre=dep;
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dep=(struct xiafs_direct *)(bh->b_data + pos);
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}
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brelse(bh);
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if (pos > XIAFS_ZSIZE(inode->i_sb)) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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return NULL;
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}
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}
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return NULL;
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}
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int xiafs_lookup(struct inode * dir, const char * name, int len,
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struct inode ** result)
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{
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int ino;
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struct xiafs_direct * dep;
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struct buffer_head * bh;
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*result = NULL;
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if (!dir)
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return -ENOENT;
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if (!S_ISDIR(dir->i_mode)) {
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iput(dir);
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return -ENOENT;
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}
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if (!(bh = xiafs_find_entry(dir, name, len, &dep, NULL))) {
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iput(dir);
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return -ENOENT;
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}
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ino = dep->d_ino;
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brelse(bh);
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if (!(*result = iget(dir->i_sb, ino))) {
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iput(dir);
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return -EACCES;
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}
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iput(dir);
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return 0;
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}
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/*
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* xiafs_add_entry()
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*
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* adds a file entry to the specified directory, using the same
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* semantics as xiafs_find_entry(). It returns NULL if it failed.
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*
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* NOTE!! The inode part of 'de' is left at 0 - which means you
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* may not sleep between calling this and putting something into
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* the entry, as someone else might have used it while you slept.
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*/
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static struct buffer_head * xiafs_add_entry(struct inode * dir,
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const char * name, int namelen, struct xiafs_direct ** res_dir,
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struct xiafs_direct ** res_pre)
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{
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int i, pos, offset;
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struct buffer_head * bh;
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struct xiafs_direct * de, * de_pre;
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*res_dir = NULL;
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if (!dir || !namelen || namelen > _XIAFS_NAME_LEN)
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return NULL;
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if (dir->i_size & (XIAFS_ZSIZE(dir->i_sb) - 1)) {
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printk("XIA-FS: bad dir size (%s %d)\n", WHERE_ERR);
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return NULL;
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}
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pos=0;
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for ( ; ; ) {
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bh = xiafs_bread(dir, pos >> XIAFS_ZSIZE_BITS(dir->i_sb), pos ? 1:0);
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if (!bh)
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return NULL;
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de_pre=de=(struct xiafs_direct *)bh->b_data;
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if (!pos) {
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if (de->d_rec_len != 12 || !de->d_ino || de->d_name_len != 1 ||
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strcmp(de->d_name, ".")) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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brelse(bh);
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return NULL;
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}
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offset = 12;
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de_pre=de=(struct xiafs_direct *)(bh->b_data+12);
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} else
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offset = 0;
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while (offset < XIAFS_ZSIZE(dir->i_sb)) {
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if (pos >= dir->i_size) {
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de->d_ino=0;
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de->d_name_len=0;
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de->d_name[0]=0;
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de->d_rec_len=XIAFS_ZSIZE(dir->i_sb);
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dir->i_size += XIAFS_ZSIZE(dir->i_sb);
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dir->i_dirt = 1;
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} else {
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if (de->d_ino > dir->i_sb->u.xiafs_sb.s_ninodes ||
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de->d_rec_len < 12 ||
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(char *)de+de->d_rec_len > bh->b_data+XIAFS_ZSIZE(dir->i_sb) ||
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de->d_name_len + 8 > de->d_rec_len ||
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de->d_name[de->d_name_len]) {
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printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
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brelse(bh);
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return NULL;
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}
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if (de->d_ino &&
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RNDUP4(de->d_name_len)+RNDUP4(namelen)+16<=de->d_rec_len) {
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i=RNDUP4(de->d_name_len)+8;
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de_pre=de;
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de=(struct xiafs_direct *)(i+(u_char *)de_pre);
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de->d_ino=0;
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de->d_rec_len=de_pre->d_rec_len-i;
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de_pre->d_rec_len=i;
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}
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}
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if (!de->d_ino && RNDUP4(namelen)+8 <= de->d_rec_len) {
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/*
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* XXX all times should be set by caller upon successful
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* completion.
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*/
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dir->i_ctime = dir->i_mtime = CURRENT_TIME;
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dir->i_dirt = 1;
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memcpy(de->d_name, name, namelen);
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de->d_name[namelen]=0;
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de->d_name_len=namelen;
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bh->b_dirt = 1;
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*res_dir = de;
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if (res_pre)
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*res_pre = de_pre;
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return bh;
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}
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offset+=de->d_rec_len;
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de_pre=de;
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de=(struct xiafs_direct *)(bh->b_data+offset);
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}
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brelse(bh);
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if (offset > XIAFS_ZSIZE(dir->i_sb)) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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return NULL;
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}
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pos+=XIAFS_ZSIZE(dir->i_sb);
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}
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return NULL;
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}
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int xiafs_create(struct inode * dir, const char * name, int len, int mode,
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struct inode ** result)
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{
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struct inode * inode;
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struct buffer_head * bh;
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struct xiafs_direct * de;
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*result = NULL;
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if (!dir)
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return -ENOENT;
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inode = xiafs_new_inode(dir);
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if (!inode) {
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iput(dir);
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return -ENOSPC;
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}
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inode->i_op = &xiafs_file_inode_operations;
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inode->i_mode = mode;
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inode->i_dirt = 1;
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bh = xiafs_add_entry(dir, name, len, &de, NULL);
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if (!bh) {
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inode->i_nlink--;
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inode->i_dirt = 1;
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iput(inode);
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iput(dir);
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return -ENOSPC;
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}
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de->d_ino = inode->i_ino;
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bh->b_dirt = 1;
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brelse(bh);
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iput(dir);
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*result = inode;
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return 0;
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}
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int xiafs_mknod(struct inode *dir, const char *name, int len, int mode, int rdev)
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{
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struct inode * inode;
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struct buffer_head * bh;
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struct xiafs_direct * de;
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if (!dir)
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return -ENOENT;
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bh = xiafs_find_entry(dir,name,len,&de, NULL);
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if (bh) {
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brelse(bh);
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iput(dir);
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return -EEXIST;
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}
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inode = xiafs_new_inode(dir);
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if (!inode) {
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iput(dir);
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return -ENOSPC;
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}
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inode->i_uid = current->euid;
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inode->i_mode = mode;
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inode->i_op = NULL;
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if (S_ISREG(inode->i_mode))
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inode->i_op = &xiafs_file_inode_operations;
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else if (S_ISDIR(inode->i_mode)) {
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inode->i_op = &xiafs_dir_inode_operations;
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if (dir->i_mode & S_ISGID)
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inode->i_mode |= S_ISGID;
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}
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else if (S_ISLNK(inode->i_mode))
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inode->i_op = &xiafs_symlink_inode_operations;
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else if (S_ISCHR(inode->i_mode))
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inode->i_op = &chrdev_inode_operations;
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else if (S_ISBLK(inode->i_mode))
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inode->i_op = &blkdev_inode_operations;
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else if (S_ISFIFO(inode->i_mode))
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init_fifo(inode);
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if (S_ISBLK(mode) || S_ISCHR(mode))
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inode->i_rdev = rdev;
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inode->i_atime = inode->i_ctime = inode->i_atime = CURRENT_TIME;
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inode->i_dirt = 1;
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bh = xiafs_add_entry(dir, name, len, &de, NULL);
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if (!bh) {
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inode->i_nlink--;
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inode->i_dirt = 1;
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iput(inode);
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iput(dir);
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return -ENOSPC;
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}
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de->d_ino = inode->i_ino;
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bh->b_dirt = 1;
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brelse(bh);
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iput(dir);
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iput(inode);
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return 0;
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}
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int xiafs_mkdir(struct inode * dir, const char * name, int len, int mode)
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{
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struct inode * inode;
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struct buffer_head * bh, *dir_block;
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struct xiafs_direct * de;
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bh = xiafs_find_entry(dir,name,len,&de, NULL);
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if (bh) {
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brelse(bh);
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iput(dir);
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return -EEXIST;
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}
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if (dir->i_nlink > 64000) {
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iput(dir);
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return -EMLINK;
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}
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inode = xiafs_new_inode(dir);
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if (!inode) {
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iput(dir);
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return -ENOSPC;
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}
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inode->i_op = &xiafs_dir_inode_operations;
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inode->i_size = XIAFS_ZSIZE(dir->i_sb);
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inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME;
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dir_block = xiafs_bread(inode,0,1);
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if (!dir_block) {
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iput(dir);
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inode->i_nlink--;
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inode->i_dirt = 1;
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iput(inode);
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return -ENOSPC;
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}
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de = (struct xiafs_direct *) dir_block->b_data;
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de->d_ino=inode->i_ino;
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strcpy(de->d_name,".");
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de->d_name_len=1;
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de->d_rec_len=12;
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de =(struct xiafs_direct *)(12 + dir_block->b_data);
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de->d_ino = dir->i_ino;
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strcpy(de->d_name,"..");
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de->d_name_len=2;
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de->d_rec_len=XIAFS_ZSIZE(dir->i_sb)-12;
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inode->i_nlink = 2;
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dir_block->b_dirt = 1;
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brelse(dir_block);
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inode->i_mode = S_IFDIR | (mode & S_IRWXUGO & ~current->umask);
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if (dir->i_mode & S_ISGID)
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inode->i_mode |= S_ISGID;
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inode->i_dirt = 1;
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bh = xiafs_add_entry(dir, name, len, &de, NULL);
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if (!bh) {
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iput(dir);
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inode->i_nlink=0;
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iput(inode);
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return -ENOSPC;
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}
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de->d_ino = inode->i_ino;
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bh->b_dirt = 1;
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dir->i_nlink++;
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dir->i_dirt = 1;
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iput(dir);
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iput(inode);
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brelse(bh);
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return 0;
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}
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/*
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* routine to check that the specified directory is empty (for rmdir)
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*/
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static int empty_dir(struct inode * inode)
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{
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int i, zones, offset;
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struct buffer_head * bh;
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struct xiafs_direct * de;
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if (inode->i_size & (XIAFS_ZSIZE(inode->i_sb)-1) ) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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return 1;
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}
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zones=inode->i_size >> XIAFS_ZSIZE_BITS(inode->i_sb);
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for (i=0; i < zones; i++) {
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bh = xiafs_bread(inode, i, 0);
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if (!i) {
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if (!bh) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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return 1;
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}
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de=(struct xiafs_direct *)bh->b_data;
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if (de->d_ino != inode->i_ino || strcmp(".", de->d_name) ||
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de->d_rec_len != 12 ) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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brelse(bh);
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return 1;
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}
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de=(struct xiafs_direct *)(12 + bh->b_data);
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if (!de->d_ino || strcmp("..", de->d_name)) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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brelse(bh);
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return 1;
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}
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offset=de->d_rec_len+12;
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}
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else
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offset = 0;
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if (!bh)
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continue;
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while (offset < XIAFS_ZSIZE(inode->i_sb)) {
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de=(struct xiafs_direct *)(bh->b_data+offset);
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if (de->d_ino > inode->i_sb->u.xiafs_sb.s_ninodes ||
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de->d_rec_len < 12 ||
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(char *)de+de->d_rec_len > bh->b_data+XIAFS_ZSIZE(inode->i_sb) ||
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de->d_name_len + 8 > de->d_rec_len ||
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de->d_name[de->d_name_len]) {
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printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
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brelse(bh);
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return 1;
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}
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if (de->d_ino) {
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brelse(bh);
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return 0;
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}
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offset+=de->d_rec_len;
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}
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brelse(bh);
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}
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return 1;
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}
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static void xiafs_rm_entry(struct xiafs_direct *de, struct xiafs_direct * de_pre)
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{
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if (de==de_pre) {
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de->d_ino=0;
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return;
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}
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while (de_pre->d_rec_len+(u_char *)de_pre < (u_char *)de) {
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if (de_pre->d_rec_len < 12) {
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printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
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return;
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}
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de_pre=(struct xiafs_direct *)(de_pre->d_rec_len+(u_char *)de_pre);
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}
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if (de_pre->d_rec_len+(u_char *)de_pre > (u_char *)de) {
|
|
printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
|
|
return;
|
|
}
|
|
de_pre->d_rec_len+=de->d_rec_len;
|
|
}
|
|
|
|
int xiafs_rmdir(struct inode * dir, const char * name, int len)
|
|
{
|
|
int retval;
|
|
struct inode * inode;
|
|
struct buffer_head * bh;
|
|
struct xiafs_direct * de, * de_pre;
|
|
|
|
inode = NULL;
|
|
bh = xiafs_find_entry(dir, name, len, &de, &de_pre);
|
|
retval = -ENOENT;
|
|
if (!bh)
|
|
goto end_rmdir;
|
|
retval = -EPERM;
|
|
if (!(inode = iget(dir->i_sb, de->d_ino)))
|
|
goto end_rmdir;
|
|
if ((dir->i_mode & S_ISVTX) && current->euid &&
|
|
inode->i_uid != current->euid)
|
|
goto end_rmdir;
|
|
if (inode->i_dev != dir->i_dev)
|
|
goto end_rmdir;
|
|
if (inode == dir) /* we may not delete ".", but "../dir" is ok */
|
|
goto end_rmdir;
|
|
if (!S_ISDIR(inode->i_mode)) {
|
|
retval = -ENOTDIR;
|
|
goto end_rmdir;
|
|
}
|
|
if (!empty_dir(inode)) {
|
|
retval = -ENOTEMPTY;
|
|
goto end_rmdir;
|
|
}
|
|
if (inode->i_count > 1) {
|
|
retval = -EBUSY;
|
|
goto end_rmdir;
|
|
}
|
|
if (inode->i_nlink != 2)
|
|
printk("XIA-FS: empty directory has nlink!=2 (%s %d)\n", WHERE_ERR);
|
|
xiafs_rm_entry(de, de_pre);
|
|
bh->b_dirt = 1;
|
|
inode->i_nlink=0;
|
|
inode->i_dirt=1;
|
|
dir->i_nlink--;
|
|
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
|
|
dir->i_dirt=1;
|
|
retval = 0;
|
|
end_rmdir:
|
|
iput(dir);
|
|
iput(inode);
|
|
brelse(bh);
|
|
return retval;
|
|
}
|
|
|
|
int xiafs_unlink(struct inode * dir, const char * name, int len)
|
|
{
|
|
int retval;
|
|
struct inode * inode;
|
|
struct buffer_head * bh;
|
|
struct xiafs_direct * de, * de_pre;
|
|
|
|
repeat:
|
|
retval = -ENOENT;
|
|
inode = NULL;
|
|
bh = xiafs_find_entry(dir, name, len, &de, &de_pre);
|
|
if (!bh)
|
|
goto end_unlink;
|
|
if (!(inode = iget(dir->i_sb, de->d_ino)))
|
|
goto end_unlink;
|
|
retval = -EPERM;
|
|
if (S_ISDIR(inode->i_mode))
|
|
goto end_unlink;
|
|
if (de->d_ino != inode->i_ino) {
|
|
iput(inode);
|
|
brelse(bh);
|
|
current->counter = 0;
|
|
schedule();
|
|
goto repeat;
|
|
}
|
|
if ((dir->i_mode & S_ISVTX) && !suser() &&
|
|
current->euid != inode->i_uid &&
|
|
current->euid != dir->i_uid)
|
|
goto end_unlink;
|
|
if (!inode->i_nlink) {
|
|
printk("XIA-FS: Deleting nonexistent file (%s %d)\n", WHERE_ERR);
|
|
inode->i_nlink=1;
|
|
}
|
|
xiafs_rm_entry(de, de_pre);
|
|
bh->b_dirt = 1;
|
|
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
|
|
dir->i_dirt = 1;
|
|
inode->i_nlink--;
|
|
inode->i_dirt = 1;
|
|
retval = 0;
|
|
end_unlink:
|
|
brelse(bh);
|
|
iput(inode);
|
|
iput(dir);
|
|
return retval;
|
|
}
|
|
|
|
int xiafs_symlink(struct inode * dir, const char * name,
|
|
int len, const char * symname)
|
|
{
|
|
struct xiafs_direct * de;
|
|
struct inode * inode = NULL;
|
|
struct buffer_head * bh = NULL, * name_block = NULL;
|
|
int i;
|
|
char c;
|
|
|
|
bh = xiafs_find_entry(dir,name,len, &de, NULL);
|
|
if (bh) {
|
|
brelse(bh);
|
|
iput(dir);
|
|
return -EEXIST;
|
|
}
|
|
if (!(inode = xiafs_new_inode(dir))) {
|
|
iput(dir);
|
|
return -ENOSPC;
|
|
}
|
|
inode->i_mode = S_IFLNK | S_IRWXUGO;
|
|
inode->i_op = &xiafs_symlink_inode_operations;
|
|
name_block = xiafs_bread(inode,0,1);
|
|
if (!name_block) {
|
|
iput(dir);
|
|
inode->i_nlink--;
|
|
inode->i_dirt = 1;
|
|
iput(inode);
|
|
return -ENOSPC;
|
|
}
|
|
for (i = 0; i < BLOCK_SIZE-1 && (c=*symname++); i++)
|
|
name_block->b_data[i] = c;
|
|
name_block->b_data[i] = 0;
|
|
name_block->b_dirt = 1;
|
|
brelse(name_block);
|
|
inode->i_size = i;
|
|
inode->i_dirt = 1;
|
|
bh = xiafs_add_entry(dir, name, len, &de, NULL);
|
|
if (!bh) {
|
|
inode->i_nlink--;
|
|
inode->i_dirt = 1;
|
|
iput(inode);
|
|
iput(dir);
|
|
return -ENOSPC;
|
|
}
|
|
de->d_ino = inode->i_ino;
|
|
bh->b_dirt = 1;
|
|
brelse(bh);
|
|
iput(dir);
|
|
iput(inode);
|
|
return 0;
|
|
}
|
|
|
|
int xiafs_link(struct inode * oldinode, struct inode * dir,
|
|
const char * name, int len)
|
|
{
|
|
struct xiafs_direct * de;
|
|
struct buffer_head * bh;
|
|
|
|
if (S_ISDIR(oldinode->i_mode)) {
|
|
iput(oldinode);
|
|
iput(dir);
|
|
return -EPERM;
|
|
}
|
|
if (oldinode->i_nlink > 64000) {
|
|
iput(oldinode);
|
|
iput(dir);
|
|
return -EMLINK;
|
|
}
|
|
bh = xiafs_find_entry(dir, name, len, &de, NULL);
|
|
if (bh) {
|
|
brelse(bh);
|
|
iput(dir);
|
|
iput(oldinode);
|
|
return -EEXIST;
|
|
}
|
|
bh = xiafs_add_entry(dir, name, len, &de, NULL);
|
|
if (!bh) {
|
|
iput(dir);
|
|
iput(oldinode);
|
|
return -ENOSPC;
|
|
}
|
|
de->d_ino = oldinode->i_ino;
|
|
bh->b_dirt = 1;
|
|
brelse(bh);
|
|
iput(dir);
|
|
oldinode->i_nlink++;
|
|
oldinode->i_ctime = CURRENT_TIME;
|
|
oldinode->i_dirt = 1;
|
|
iput(oldinode);
|
|
return 0;
|
|
}
|
|
|
|
static int subdir(struct inode * new_inode, struct inode * old_inode)
|
|
{
|
|
int ino;
|
|
int result;
|
|
|
|
new_inode->i_count++;
|
|
result = 0;
|
|
for (;;) {
|
|
if (new_inode == old_inode) {
|
|
result = 1;
|
|
break;
|
|
}
|
|
if (new_inode->i_dev != old_inode->i_dev)
|
|
break;
|
|
ino = new_inode->i_ino;
|
|
if (xiafs_lookup(new_inode,"..",2,&new_inode))
|
|
break;
|
|
if (new_inode->i_ino == ino)
|
|
break;
|
|
}
|
|
iput(new_inode);
|
|
return result;
|
|
}
|
|
|
|
#define PARENT_INO(buffer) \
|
|
(((struct xiafs_direct *) ((u_char *)(buffer) + 12))->d_ino)
|
|
|
|
/*
|
|
* rename uses retry to avoid race-conditions: at least they should be minimal.
|
|
* it tries to allocate all the blocks, then sanity-checks, and if the sanity-
|
|
* checks fail, it tries to restart itself again. Very practical - no changes
|
|
* are done until we know everything works ok.. and then all the changes can be
|
|
* done in one fell swoop when we have claimed all the buffers needed.
|
|
*
|
|
* Anybody can rename anything with this: the permission checks are left to the
|
|
* higher-level routines.
|
|
*/
|
|
static int do_xiafs_rename(struct inode * old_dir, const char * old_name,
|
|
int old_len, struct inode * new_dir,
|
|
const char * new_name, int new_len)
|
|
{
|
|
struct inode * old_inode, * new_inode;
|
|
struct buffer_head * old_bh, * new_bh, * dir_bh;
|
|
struct xiafs_direct * old_de, * old_de_pre, * new_de, * new_de_pre;
|
|
int retval;
|
|
|
|
try_again:
|
|
old_inode = new_inode = NULL;
|
|
old_bh = new_bh = dir_bh = NULL;
|
|
old_bh = xiafs_find_entry(old_dir, old_name, old_len, &old_de, &old_de_pre);
|
|
retval = -ENOENT;
|
|
if (!old_bh)
|
|
goto end_rename;
|
|
old_inode = __iget(old_dir->i_sb, old_de->d_ino, 0); /* don't cross mnt-points */
|
|
if (!old_inode)
|
|
goto end_rename;
|
|
retval = -EPERM;
|
|
if ((old_dir->i_mode & S_ISVTX) &&
|
|
current->euid != old_inode->i_uid &&
|
|
current->euid != old_dir->i_uid && !suser())
|
|
goto end_rename;
|
|
new_bh = xiafs_find_entry(new_dir, new_name, new_len, &new_de, NULL);
|
|
if (new_bh) {
|
|
new_inode = __iget(new_dir->i_sb, new_de->d_ino, 0);
|
|
if (!new_inode) {
|
|
brelse(new_bh);
|
|
new_bh = NULL;
|
|
}
|
|
}
|
|
if (new_inode == old_inode) {
|
|
retval = 0;
|
|
goto end_rename;
|
|
}
|
|
if (new_inode && S_ISDIR(new_inode->i_mode)) {
|
|
retval = -EEXIST;
|
|
goto end_rename;
|
|
}
|
|
retval = -EPERM;
|
|
if (new_inode && (new_dir->i_mode & S_ISVTX) &&
|
|
current->euid != new_inode->i_uid &&
|
|
current->euid != new_dir->i_uid && !suser())
|
|
goto end_rename;
|
|
if (S_ISDIR(old_inode->i_mode)) {
|
|
retval = -EEXIST;
|
|
if (new_bh)
|
|
goto end_rename;
|
|
retval = -EACCES;
|
|
if (!permission(old_inode, MAY_WRITE))
|
|
goto end_rename;
|
|
retval = -EINVAL;
|
|
if (subdir(new_dir, old_inode))
|
|
goto end_rename;
|
|
retval = -EIO;
|
|
dir_bh = xiafs_bread(old_inode,0,0);
|
|
if (!dir_bh)
|
|
goto end_rename;
|
|
if (PARENT_INO(dir_bh->b_data) != old_dir->i_ino)
|
|
goto end_rename;
|
|
retval = -EMLINK;
|
|
if (new_dir->i_nlink > 64000)
|
|
goto end_rename;
|
|
}
|
|
if (!new_bh)
|
|
new_bh = xiafs_add_entry(new_dir, new_name, new_len, &new_de, &new_de_pre);
|
|
retval = -ENOSPC;
|
|
if (!new_bh)
|
|
goto end_rename;
|
|
/* sanity checking */
|
|
if ( (new_inode && (new_de->d_ino != new_inode->i_ino))
|
|
|| (new_de->d_ino && !new_inode)
|
|
|| (old_de->d_ino != old_inode->i_ino)) {
|
|
xiafs_rm_entry(new_de, new_de_pre);
|
|
brelse(old_bh);
|
|
brelse(new_bh);
|
|
brelse(dir_bh);
|
|
iput(old_inode);
|
|
iput(new_inode);
|
|
current->counter=0;
|
|
schedule();
|
|
goto try_again;
|
|
}
|
|
xiafs_rm_entry(old_de, old_de_pre);
|
|
new_de->d_ino = old_inode->i_ino;
|
|
if (new_inode) {
|
|
new_inode->i_nlink--;
|
|
new_inode->i_dirt = 1;
|
|
}
|
|
old_bh->b_dirt = 1;
|
|
new_bh->b_dirt = 1;
|
|
if (dir_bh) {
|
|
PARENT_INO(dir_bh->b_data) = new_dir->i_ino;
|
|
dir_bh->b_dirt = 1;
|
|
old_dir->i_nlink--;
|
|
new_dir->i_nlink++;
|
|
old_dir->i_dirt = 1;
|
|
new_dir->i_dirt = 1;
|
|
}
|
|
retval = 0;
|
|
end_rename:
|
|
brelse(dir_bh);
|
|
brelse(old_bh);
|
|
brelse(new_bh);
|
|
iput(old_inode);
|
|
iput(new_inode);
|
|
iput(old_dir);
|
|
iput(new_dir);
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* Ok, rename also locks out other renames, as they can change the parent of
|
|
* a directory, and we don't want any races. Other races are checked for by
|
|
* "do_rename()", which restarts if there are inconsistencies.
|
|
*
|
|
* Note that there is no race between different filesystems: it's only within
|
|
* the same device that races occur: many renames can happen at once, as long
|
|
* as they are on different partitions.
|
|
*/
|
|
int xiafs_rename(struct inode * old_dir, const char * old_name, int old_len,
|
|
struct inode * new_dir, const char * new_name, int new_len)
|
|
{
|
|
static struct wait_queue * wait = NULL;
|
|
static int lock = 0;
|
|
int result;
|
|
|
|
while (lock)
|
|
sleep_on(&wait);
|
|
lock = 1;
|
|
result = do_xiafs_rename(old_dir, old_name, old_len,
|
|
new_dir, new_name, new_len);
|
|
lock = 0;
|
|
wake_up(&wait);
|
|
return result;
|
|
}
|