mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Russell King](/assets/img/avatar_default.png)
Avoid using the inode number as the indirect disc address, even though these currently have the same value. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
457 lines
9.5 KiB
C
457 lines
9.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* linux/fs/adfs/dir.c
|
|
*
|
|
* Copyright (C) 1999-2000 Russell King
|
|
*
|
|
* Common directory handling for ADFS
|
|
*/
|
|
#include <linux/slab.h>
|
|
#include "adfs.h"
|
|
|
|
/*
|
|
* For future. This should probably be per-directory.
|
|
*/
|
|
static DECLARE_RWSEM(adfs_dir_rwsem);
|
|
|
|
int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset,
|
|
size_t len)
|
|
{
|
|
struct super_block *sb = dir->sb;
|
|
unsigned int index, remain;
|
|
|
|
index = offset >> sb->s_blocksize_bits;
|
|
offset &= sb->s_blocksize - 1;
|
|
remain = sb->s_blocksize - offset;
|
|
if (index + (remain < len) >= dir->nr_buffers)
|
|
return -EINVAL;
|
|
|
|
if (remain < len) {
|
|
memcpy(dst, dir->bhs[index]->b_data + offset, remain);
|
|
dst += remain;
|
|
len -= remain;
|
|
index += 1;
|
|
offset = 0;
|
|
}
|
|
|
|
memcpy(dst, dir->bhs[index]->b_data + offset, len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src,
|
|
size_t len)
|
|
{
|
|
struct super_block *sb = dir->sb;
|
|
unsigned int index, remain;
|
|
|
|
index = offset >> sb->s_blocksize_bits;
|
|
offset &= sb->s_blocksize - 1;
|
|
remain = sb->s_blocksize - offset;
|
|
if (index + (remain < len) >= dir->nr_buffers)
|
|
return -EINVAL;
|
|
|
|
if (remain < len) {
|
|
memcpy(dir->bhs[index]->b_data + offset, src, remain);
|
|
src += remain;
|
|
len -= remain;
|
|
index += 1;
|
|
offset = 0;
|
|
}
|
|
|
|
memcpy(dir->bhs[index]->b_data + offset, src, len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __adfs_dir_cleanup(struct adfs_dir *dir)
|
|
{
|
|
dir->nr_buffers = 0;
|
|
|
|
if (dir->bhs != dir->bh)
|
|
kfree(dir->bhs);
|
|
dir->bhs = NULL;
|
|
dir->sb = NULL;
|
|
}
|
|
|
|
void adfs_dir_relse(struct adfs_dir *dir)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < dir->nr_buffers; i++)
|
|
brelse(dir->bhs[i]);
|
|
|
|
__adfs_dir_cleanup(dir);
|
|
}
|
|
|
|
static void adfs_dir_forget(struct adfs_dir *dir)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < dir->nr_buffers; i++)
|
|
bforget(dir->bhs[i]);
|
|
|
|
__adfs_dir_cleanup(dir);
|
|
}
|
|
|
|
int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr,
|
|
unsigned int size, struct adfs_dir *dir)
|
|
{
|
|
struct buffer_head **bhs;
|
|
unsigned int i, num;
|
|
int block;
|
|
|
|
num = ALIGN(size, sb->s_blocksize) >> sb->s_blocksize_bits;
|
|
if (num > ARRAY_SIZE(dir->bh)) {
|
|
/* We only allow one extension */
|
|
if (dir->bhs != dir->bh)
|
|
return -EINVAL;
|
|
|
|
bhs = kcalloc(num, sizeof(*bhs), GFP_KERNEL);
|
|
if (!bhs)
|
|
return -ENOMEM;
|
|
|
|
if (dir->nr_buffers)
|
|
memcpy(bhs, dir->bhs, dir->nr_buffers * sizeof(*bhs));
|
|
|
|
dir->bhs = bhs;
|
|
}
|
|
|
|
for (i = dir->nr_buffers; i < num; i++) {
|
|
block = __adfs_block_map(sb, indaddr, i);
|
|
if (!block) {
|
|
adfs_error(sb, "dir %06x has a hole at offset %u",
|
|
indaddr, i);
|
|
goto error;
|
|
}
|
|
|
|
dir->bhs[i] = sb_bread(sb, block);
|
|
if (!dir->bhs[i]) {
|
|
adfs_error(sb,
|
|
"dir %06x failed read at offset %u, mapped block 0x%08x",
|
|
indaddr, i, block);
|
|
goto error;
|
|
}
|
|
|
|
dir->nr_buffers++;
|
|
}
|
|
return 0;
|
|
|
|
error:
|
|
adfs_dir_relse(dir);
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
static int adfs_dir_read(struct super_block *sb, u32 indaddr,
|
|
unsigned int size, struct adfs_dir *dir)
|
|
{
|
|
dir->sb = sb;
|
|
dir->bhs = dir->bh;
|
|
dir->nr_buffers = 0;
|
|
|
|
return ADFS_SB(sb)->s_dir->read(sb, indaddr, size, dir);
|
|
}
|
|
|
|
static int adfs_dir_read_inode(struct super_block *sb, struct inode *inode,
|
|
struct adfs_dir *dir)
|
|
{
|
|
int ret;
|
|
|
|
ret = adfs_dir_read(sb, ADFS_I(inode)->indaddr, inode->i_size, dir);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (ADFS_I(inode)->parent_id != dir->parent_id) {
|
|
adfs_error(sb,
|
|
"parent directory id changed under me! (%06x but got %06x)\n",
|
|
ADFS_I(inode)->parent_id, dir->parent_id);
|
|
adfs_dir_relse(dir);
|
|
ret = -EIO;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void adfs_dir_mark_dirty(struct adfs_dir *dir)
|
|
{
|
|
unsigned int i;
|
|
|
|
/* Mark the buffers dirty */
|
|
for (i = 0; i < dir->nr_buffers; i++)
|
|
mark_buffer_dirty(dir->bhs[i]);
|
|
}
|
|
|
|
static int adfs_dir_sync(struct adfs_dir *dir)
|
|
{
|
|
int err = 0;
|
|
int i;
|
|
|
|
for (i = dir->nr_buffers - 1; i >= 0; i--) {
|
|
struct buffer_head *bh = dir->bhs[i];
|
|
sync_dirty_buffer(bh);
|
|
if (buffer_req(bh) && !buffer_uptodate(bh))
|
|
err = -EIO;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj)
|
|
{
|
|
unsigned int dots, i;
|
|
|
|
/*
|
|
* RISC OS allows the use of '/' in directory entry names, so we need
|
|
* to fix these up. '/' is typically used for FAT compatibility to
|
|
* represent '.', so do the same conversion here. In any case, '.'
|
|
* will never be in a RISC OS name since it is used as the pathname
|
|
* separator. Handle the case where we may generate a '.' or '..'
|
|
* name, replacing the first character with '^' (the RISC OS "parent
|
|
* directory" character.)
|
|
*/
|
|
for (i = dots = 0; i < obj->name_len; i++)
|
|
if (obj->name[i] == '/') {
|
|
obj->name[i] = '.';
|
|
dots++;
|
|
}
|
|
|
|
if (obj->name_len <= 2 && dots == obj->name_len)
|
|
obj->name[0] = '^';
|
|
|
|
/*
|
|
* If the object is a file, and the user requested the ,xyz hex
|
|
* filetype suffix to the name, check the filetype and append.
|
|
*/
|
|
if (!(obj->attr & ADFS_NDA_DIRECTORY) && ADFS_SB(dir->sb)->s_ftsuffix) {
|
|
u16 filetype = adfs_filetype(obj->loadaddr);
|
|
|
|
if (filetype != ADFS_FILETYPE_NONE) {
|
|
obj->name[obj->name_len++] = ',';
|
|
obj->name[obj->name_len++] = hex_asc_lo(filetype >> 8);
|
|
obj->name[obj->name_len++] = hex_asc_lo(filetype >> 4);
|
|
obj->name[obj->name_len++] = hex_asc_lo(filetype >> 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int adfs_iterate(struct file *file, struct dir_context *ctx)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct super_block *sb = inode->i_sb;
|
|
const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
|
|
struct adfs_dir dir;
|
|
int ret;
|
|
|
|
down_read(&adfs_dir_rwsem);
|
|
ret = adfs_dir_read_inode(sb, inode, &dir);
|
|
if (ret)
|
|
goto unlock;
|
|
|
|
if (ctx->pos == 0) {
|
|
if (!dir_emit_dot(file, ctx))
|
|
goto unlock_relse;
|
|
ctx->pos = 1;
|
|
}
|
|
if (ctx->pos == 1) {
|
|
if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR))
|
|
goto unlock_relse;
|
|
ctx->pos = 2;
|
|
}
|
|
|
|
ret = ops->iterate(&dir, ctx);
|
|
|
|
unlock_relse:
|
|
up_read(&adfs_dir_rwsem);
|
|
adfs_dir_relse(&dir);
|
|
return ret;
|
|
|
|
unlock:
|
|
up_read(&adfs_dir_rwsem);
|
|
return ret;
|
|
}
|
|
|
|
int
|
|
adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait)
|
|
{
|
|
const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
|
|
struct adfs_dir dir;
|
|
int ret;
|
|
|
|
if (!IS_ENABLED(CONFIG_ADFS_FS_RW))
|
|
return -EINVAL;
|
|
|
|
if (!ops->update)
|
|
return -EINVAL;
|
|
|
|
down_write(&adfs_dir_rwsem);
|
|
ret = adfs_dir_read(sb, obj->parent_id, 0, &dir);
|
|
if (ret)
|
|
goto unlock;
|
|
|
|
ret = ops->update(&dir, obj);
|
|
if (ret)
|
|
goto forget;
|
|
|
|
ret = ops->commit(&dir);
|
|
if (ret)
|
|
goto forget;
|
|
up_write(&adfs_dir_rwsem);
|
|
|
|
adfs_dir_mark_dirty(&dir);
|
|
|
|
if (wait)
|
|
ret = adfs_dir_sync(&dir);
|
|
|
|
adfs_dir_relse(&dir);
|
|
return ret;
|
|
|
|
/*
|
|
* If the updated failed because the entry wasn't found, we can
|
|
* just release the buffers. If it was any other error, forget
|
|
* the dirtied buffers so they aren't written back to the media.
|
|
*/
|
|
forget:
|
|
if (ret == -ENOENT)
|
|
adfs_dir_relse(&dir);
|
|
else
|
|
adfs_dir_forget(&dir);
|
|
unlock:
|
|
up_write(&adfs_dir_rwsem);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static unsigned char adfs_tolower(unsigned char c)
|
|
{
|
|
if (c >= 'A' && c <= 'Z')
|
|
c += 'a' - 'A';
|
|
return c;
|
|
}
|
|
|
|
static int __adfs_compare(const unsigned char *qstr, u32 qlen,
|
|
const char *str, u32 len)
|
|
{
|
|
u32 i;
|
|
|
|
if (qlen != len)
|
|
return 1;
|
|
|
|
for (i = 0; i < qlen; i++)
|
|
if (adfs_tolower(qstr[i]) != adfs_tolower(str[i]))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int adfs_dir_lookup_byname(struct inode *inode, const struct qstr *qstr,
|
|
struct object_info *obj)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
|
|
const unsigned char *name;
|
|
struct adfs_dir dir;
|
|
u32 name_len;
|
|
int ret;
|
|
|
|
down_read(&adfs_dir_rwsem);
|
|
ret = adfs_dir_read_inode(sb, inode, &dir);
|
|
if (ret)
|
|
goto unlock;
|
|
|
|
ret = ops->setpos(&dir, 0);
|
|
if (ret)
|
|
goto unlock_relse;
|
|
|
|
ret = -ENOENT;
|
|
name = qstr->name;
|
|
name_len = qstr->len;
|
|
while (ops->getnext(&dir, obj) == 0) {
|
|
if (!__adfs_compare(name, name_len, obj->name, obj->name_len)) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
}
|
|
obj->parent_id = ADFS_I(inode)->indaddr;
|
|
|
|
unlock_relse:
|
|
up_read(&adfs_dir_rwsem);
|
|
adfs_dir_relse(&dir);
|
|
return ret;
|
|
|
|
unlock:
|
|
up_read(&adfs_dir_rwsem);
|
|
return ret;
|
|
}
|
|
|
|
const struct file_operations adfs_dir_operations = {
|
|
.read = generic_read_dir,
|
|
.llseek = generic_file_llseek,
|
|
.iterate_shared = adfs_iterate,
|
|
.fsync = generic_file_fsync,
|
|
};
|
|
|
|
static int
|
|
adfs_hash(const struct dentry *parent, struct qstr *qstr)
|
|
{
|
|
const unsigned char *name;
|
|
unsigned long hash;
|
|
u32 len;
|
|
|
|
if (qstr->len > ADFS_SB(parent->d_sb)->s_namelen)
|
|
return -ENAMETOOLONG;
|
|
|
|
len = qstr->len;
|
|
name = qstr->name;
|
|
hash = init_name_hash(parent);
|
|
while (len--)
|
|
hash = partial_name_hash(adfs_tolower(*name++), hash);
|
|
qstr->hash = end_name_hash(hash);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Compare two names, taking note of the name length
|
|
* requirements of the underlying filesystem.
|
|
*/
|
|
static int adfs_compare(const struct dentry *dentry, unsigned int len,
|
|
const char *str, const struct qstr *qstr)
|
|
{
|
|
return __adfs_compare(qstr->name, qstr->len, str, len);
|
|
}
|
|
|
|
const struct dentry_operations adfs_dentry_operations = {
|
|
.d_hash = adfs_hash,
|
|
.d_compare = adfs_compare,
|
|
};
|
|
|
|
static struct dentry *
|
|
adfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
|
|
{
|
|
struct inode *inode = NULL;
|
|
struct object_info obj;
|
|
int error;
|
|
|
|
error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj);
|
|
if (error == 0) {
|
|
/*
|
|
* This only returns NULL if get_empty_inode
|
|
* fails.
|
|
*/
|
|
inode = adfs_iget(dir->i_sb, &obj);
|
|
if (!inode)
|
|
inode = ERR_PTR(-EACCES);
|
|
} else if (error != -ENOENT) {
|
|
inode = ERR_PTR(error);
|
|
}
|
|
return d_splice_alias(inode, dentry);
|
|
}
|
|
|
|
/*
|
|
* directories can handle most operations...
|
|
*/
|
|
const struct inode_operations adfs_dir_inode_operations = {
|
|
.lookup = adfs_lookup,
|
|
.setattr = adfs_notify_change,
|
|
};
|