WSL2-Linux-Kernel/fs/hfsplus/dir.c

510 строки
12 KiB
C

/*
* linux/fs/hfsplus/dir.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Handling of directories
*/
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/random.h>
#include "hfsplus_fs.h"
#include "hfsplus_raw.h"
static inline void hfsplus_instantiate(struct dentry *dentry,
struct inode *inode, u32 cnid)
{
dentry->d_fsdata = (void *)(unsigned long)cnid;
d_instantiate(dentry, inode);
}
/* Find the entry inside dir named dentry->d_name */
static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct inode *inode = NULL;
struct hfs_find_data fd;
struct super_block *sb;
hfsplus_cat_entry entry;
int err;
u32 cnid, linkid = 0;
u16 type;
sb = dir->i_sb;
dentry->d_fsdata = NULL;
err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
if (err)
return ERR_PTR(err);
hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
again:
err = hfs_brec_read(&fd, &entry, sizeof(entry));
if (err) {
if (err == -ENOENT) {
hfs_find_exit(&fd);
/* No such entry */
inode = NULL;
goto out;
}
goto fail;
}
type = be16_to_cpu(entry.type);
if (type == HFSPLUS_FOLDER) {
if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
err = -EIO;
goto fail;
}
cnid = be32_to_cpu(entry.folder.id);
dentry->d_fsdata = (void *)(unsigned long)cnid;
} else if (type == HFSPLUS_FILE) {
if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
err = -EIO;
goto fail;
}
cnid = be32_to_cpu(entry.file.id);
if (entry.file.user_info.fdType ==
cpu_to_be32(HFSP_HARDLINK_TYPE) &&
entry.file.user_info.fdCreator ==
cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
(entry.file.create_date ==
HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)->
create_date ||
entry.file.create_date ==
HFSPLUS_I(sb->s_root->d_inode)->
create_date) &&
HFSPLUS_SB(sb)->hidden_dir) {
struct qstr str;
char name[32];
if (dentry->d_fsdata) {
/*
* We found a link pointing to another link,
* so ignore it and treat it as regular file.
*/
cnid = (unsigned long)dentry->d_fsdata;
linkid = 0;
} else {
dentry->d_fsdata = (void *)(unsigned long)cnid;
linkid =
be32_to_cpu(entry.file.permissions.dev);
str.len = sprintf(name, "iNode%d", linkid);
str.name = name;
hfsplus_cat_build_key(sb, fd.search_key,
HFSPLUS_SB(sb)->hidden_dir->i_ino,
&str);
goto again;
}
} else if (!dentry->d_fsdata)
dentry->d_fsdata = (void *)(unsigned long)cnid;
} else {
printk(KERN_ERR "hfs: invalid catalog entry type in lookup\n");
err = -EIO;
goto fail;
}
hfs_find_exit(&fd);
inode = hfsplus_iget(dir->i_sb, cnid);
if (IS_ERR(inode))
return ERR_CAST(inode);
if (S_ISREG(inode->i_mode))
HFSPLUS_I(inode)->linkid = linkid;
out:
d_add(dentry, inode);
return NULL;
fail:
hfs_find_exit(&fd);
return ERR_PTR(err);
}
static int hfsplus_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *inode = filp->f_path.dentry->d_inode;
struct super_block *sb = inode->i_sb;
int len, err;
char strbuf[HFSPLUS_MAX_STRLEN + 1];
hfsplus_cat_entry entry;
struct hfs_find_data fd;
struct hfsplus_readdir_data *rd;
u16 type;
if (filp->f_pos >= inode->i_size)
return 0;
err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
if (err)
return err;
hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
err = hfs_brec_find(&fd);
if (err)
goto out;
switch ((u32)filp->f_pos) {
case 0:
/* This is completely artificial... */
if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
goto out;
filp->f_pos++;
/* fall through */
case 1:
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
fd.entrylength);
if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
printk(KERN_ERR "hfs: bad catalog folder thread\n");
err = -EIO;
goto out;
}
if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
printk(KERN_ERR "hfs: truncated catalog thread\n");
err = -EIO;
goto out;
}
if (filldir(dirent, "..", 2, 1,
be32_to_cpu(entry.thread.parentID), DT_DIR))
goto out;
filp->f_pos++;
/* fall through */
default:
if (filp->f_pos >= inode->i_size)
goto out;
err = hfs_brec_goto(&fd, filp->f_pos - 1);
if (err)
goto out;
}
for (;;) {
if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
printk(KERN_ERR "hfs: walked past end of dir\n");
err = -EIO;
goto out;
}
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
fd.entrylength);
type = be16_to_cpu(entry.type);
len = HFSPLUS_MAX_STRLEN;
err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
if (err)
goto out;
if (type == HFSPLUS_FOLDER) {
if (fd.entrylength <
sizeof(struct hfsplus_cat_folder)) {
printk(KERN_ERR "hfs: small dir entry\n");
err = -EIO;
goto out;
}
if (HFSPLUS_SB(sb)->hidden_dir &&
HFSPLUS_SB(sb)->hidden_dir->i_ino ==
be32_to_cpu(entry.folder.id))
goto next;
if (filldir(dirent, strbuf, len, filp->f_pos,
be32_to_cpu(entry.folder.id), DT_DIR))
break;
} else if (type == HFSPLUS_FILE) {
if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
printk(KERN_ERR "hfs: small file entry\n");
err = -EIO;
goto out;
}
if (filldir(dirent, strbuf, len, filp->f_pos,
be32_to_cpu(entry.file.id), DT_REG))
break;
} else {
printk(KERN_ERR "hfs: bad catalog entry type\n");
err = -EIO;
goto out;
}
next:
filp->f_pos++;
if (filp->f_pos >= inode->i_size)
goto out;
err = hfs_brec_goto(&fd, 1);
if (err)
goto out;
}
rd = filp->private_data;
if (!rd) {
rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
if (!rd) {
err = -ENOMEM;
goto out;
}
filp->private_data = rd;
rd->file = filp;
list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
}
memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
out:
hfs_find_exit(&fd);
return err;
}
static int hfsplus_dir_release(struct inode *inode, struct file *file)
{
struct hfsplus_readdir_data *rd = file->private_data;
if (rd) {
mutex_lock(&inode->i_mutex);
list_del(&rd->list);
mutex_unlock(&inode->i_mutex);
kfree(rd);
}
return 0;
}
static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
struct dentry *dst_dentry)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
struct inode *inode = src_dentry->d_inode;
struct inode *src_dir = src_dentry->d_parent->d_inode;
struct qstr str;
char name[32];
u32 cnid, id;
int res;
if (HFSPLUS_IS_RSRC(inode))
return -EPERM;
if (!S_ISREG(inode->i_mode))
return -EPERM;
mutex_lock(&sbi->vh_mutex);
if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
for (;;) {
get_random_bytes(&id, sizeof(cnid));
id &= 0x3fffffff;
str.name = name;
str.len = sprintf(name, "iNode%d", id);
res = hfsplus_rename_cat(inode->i_ino,
src_dir, &src_dentry->d_name,
sbi->hidden_dir, &str);
if (!res)
break;
if (res != -EEXIST)
goto out;
}
HFSPLUS_I(inode)->linkid = id;
cnid = sbi->next_cnid++;
src_dentry->d_fsdata = (void *)(unsigned long)cnid;
res = hfsplus_create_cat(cnid, src_dir,
&src_dentry->d_name, inode);
if (res)
/* panic? */
goto out;
sbi->file_count++;
}
cnid = sbi->next_cnid++;
res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
if (res)
goto out;
inc_nlink(inode);
hfsplus_instantiate(dst_dentry, inode, cnid);
ihold(inode);
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
sbi->file_count++;
dst_dir->i_sb->s_dirt = 1;
out:
mutex_unlock(&sbi->vh_mutex);
return res;
}
static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
struct inode *inode = dentry->d_inode;
struct qstr str;
char name[32];
u32 cnid;
int res;
if (HFSPLUS_IS_RSRC(inode))
return -EPERM;
mutex_lock(&sbi->vh_mutex);
cnid = (u32)(unsigned long)dentry->d_fsdata;
if (inode->i_ino == cnid &&
atomic_read(&HFSPLUS_I(inode)->opencnt)) {
str.name = name;
str.len = sprintf(name, "temp%lu", inode->i_ino);
res = hfsplus_rename_cat(inode->i_ino,
dir, &dentry->d_name,
sbi->hidden_dir, &str);
if (!res) {
inode->i_flags |= S_DEAD;
drop_nlink(inode);
}
goto out;
}
res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
if (res)
goto out;
if (inode->i_nlink > 0)
drop_nlink(inode);
if (inode->i_ino == cnid)
clear_nlink(inode);
if (!inode->i_nlink) {
if (inode->i_ino != cnid) {
sbi->file_count--;
if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
res = hfsplus_delete_cat(inode->i_ino,
sbi->hidden_dir,
NULL);
if (!res)
hfsplus_delete_inode(inode);
} else
inode->i_flags |= S_DEAD;
} else
hfsplus_delete_inode(inode);
} else
sbi->file_count--;
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
out:
mutex_unlock(&sbi->vh_mutex);
return res;
}
static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
struct inode *inode = dentry->d_inode;
int res;
if (inode->i_size != 2)
return -ENOTEMPTY;
mutex_lock(&sbi->vh_mutex);
res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
if (res)
goto out;
clear_nlink(inode);
inode->i_ctime = CURRENT_TIME_SEC;
hfsplus_delete_inode(inode);
mark_inode_dirty(inode);
out:
mutex_unlock(&sbi->vh_mutex);
return res;
}
static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
struct inode *inode;
int res = -ENOSPC;
mutex_lock(&sbi->vh_mutex);
inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
if (!inode)
goto out;
res = page_symlink(inode, symname, strlen(symname) + 1);
if (res)
goto out_err;
res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
if (res)
goto out_err;
hfsplus_instantiate(dentry, inode, inode->i_ino);
mark_inode_dirty(inode);
goto out;
out_err:
clear_nlink(inode);
hfsplus_delete_inode(inode);
iput(inode);
out:
mutex_unlock(&sbi->vh_mutex);
return res;
}
static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
umode_t mode, dev_t rdev)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
struct inode *inode;
int res = -ENOSPC;
mutex_lock(&sbi->vh_mutex);
inode = hfsplus_new_inode(dir->i_sb, mode);
if (!inode)
goto out;
if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
init_special_inode(inode, mode, rdev);
res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
if (res) {
clear_nlink(inode);
hfsplus_delete_inode(inode);
iput(inode);
goto out;
}
hfsplus_instantiate(dentry, inode, inode->i_ino);
mark_inode_dirty(inode);
out:
mutex_unlock(&sbi->vh_mutex);
return res;
}
static int hfsplus_create(struct inode *dir, struct dentry *dentry, umode_t mode,
struct nameidata *nd)
{
return hfsplus_mknod(dir, dentry, mode, 0);
}
static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
}
static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
int res;
/* Unlink destination if it already exists */
if (new_dentry->d_inode) {
if (S_ISDIR(new_dentry->d_inode->i_mode))
res = hfsplus_rmdir(new_dir, new_dentry);
else
res = hfsplus_unlink(new_dir, new_dentry);
if (res)
return res;
}
res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
old_dir, &old_dentry->d_name,
new_dir, &new_dentry->d_name);
if (!res)
new_dentry->d_fsdata = old_dentry->d_fsdata;
return res;
}
const struct inode_operations hfsplus_dir_inode_operations = {
.lookup = hfsplus_lookup,
.create = hfsplus_create,
.link = hfsplus_link,
.unlink = hfsplus_unlink,
.mkdir = hfsplus_mkdir,
.rmdir = hfsplus_rmdir,
.symlink = hfsplus_symlink,
.mknod = hfsplus_mknod,
.rename = hfsplus_rename,
};
const struct file_operations hfsplus_dir_operations = {
.fsync = hfsplus_file_fsync,
.read = generic_read_dir,
.readdir = hfsplus_readdir,
.unlocked_ioctl = hfsplus_ioctl,
.llseek = generic_file_llseek,
.release = hfsplus_dir_release,
};