|
|
是我从proc改来的
hello.c
[code:1]
#include "hello.h"
struct inode * hello_get_inode(struct super_block *, int, struct hello_dir_entry *);
int hello_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
printk("hello_readdir\n");
struct hello_dir_entry * de;
unsigned int ino;
int i;
struct inode *inode = filp->f_dentry->d_inode;
ino = inode->i_ino;
de = (struct hello_dir_entry *) inode->u.generic_ip;
if (!de)
return -EINVAL;
i = filp->f_pos;
switch (i) {
case 0:
if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
return 0;
i++;
filp->f_pos++;
/* fall through */
case 1:
if (filldir(dirent, "..", 2, i,
filp->f_dentry->d_parent->d_inode->i_ino,
DT_DIR) < 0)
return 0;
i++;
filp->f_pos++;
/* fall through */
default:
de = de->subdir;
i -= 2;
for (;;) {
if (!de)
return 1;
if (!i)
break;
de = de->next;
i--;
}
do {
if (filldir(dirent, de->name, de->namelen, filp->f_pos,
de->low_ino, de->mode >> 12) < 0)
return 0;
filp->f_pos++;
de = de->next;
} while (de);
}
return 1;
}
int hello_d_revalidate(struct dentry *res, int i){printk("d_revalidate\n");return 0;}
int hello_d_hash(struct dentry *res, struct qstr *name){printk("d_hash\n");return 0;}
int hello_d_compare(struct dentry *res, struct qstr *name, struct qstr *old)
{printk("d_compare\n");return 0;}
int hello_d_delete(struct dentry *res){printk("d_delete\n");return 0;}
void hello_d_release(struct dentry *res){printk("d_release\n");}
void hello_d_iput(struct dentry *res, struct inode *inode){printk("d_iput\n");}
struct dentry_operations hello_lookup_dops = {
/*d_revalidate: hello_d_revalidate,
d_hash: hello_d_hash,
d_compare: hello_d_compare,*/
d_delete: hello_d_delete,
d_release: hello_d_release,
/*d_iput: hello_d_iput*/
};
struct dentry *hello_lookup(struct inode * dir, struct dentry *dentry)
{
struct inode *inode;
struct hello_dir_entry * de;
int error;
error = -ENOENT;
inode = NULL;
de = (struct hello_dir_entry *) dir->u.generic_ip;
if (de) {
for (de = de->subdir; de ; de = de->next) {
if (!de || !de->low_ino)
continue;
if (de->namelen != dentry->d_name.len)
continue;
if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
int ino = de->low_ino;
error = -EINVAL;
inode = hello_get_inode(dir->i_sb, ino, de);
break;
}
}
}
if (inode) {
dentry->d_op = &hello_lookup_dops;
d_add(dentry, inode);
return NULL;
}
return ERR_PTR(error);
}
/************************************************************************************************************/
static struct inode_operations hello_root_inode_operations = {
lookup: hello_lookup,
};
static struct file_operations hello_file_operations = {
readdir: hello_readdir,
};
struct hello_dir_entry hello_root = {
low_ino: HELLO_ROOT_INO,
namelen: 5,
name: "/hello",
mode: S_IFDIR | S_IRUGO | S_IXUGO,
nlink: 2,
hello_iops: &hello_root_inode_operations,
hello_fops: &hello_file_operations,
parent: &hello_root,
};
struct inode * hello_get_inode(struct super_block * sb, int ino,
struct hello_dir_entry * de)
{
printk("hello_get_inode\n");
struct inode * inode;
de_get(de);
inode = iget(sb, ino);
if (!inode)
goto out_fail;
inode->u.generic_ip = (void *) de;
if (de) {
if (de->mode) {
inode->i_mode = de->mode;
inode->i_uid = de->uid;
inode->i_gid = de->gid;
}
if (de->size)
inode->i_size = de->size;
if (de->nlink)
inode->i_nlink = de->nlink;
if (de->owner)
__MOD_INC_USE_COUNT(de->owner);
if (de->hello_iops)
inode->i_op = de->hello_iops;
if (de->hello_fops)
inode->i_fop = de->hello_fops;
}
out:
return inode;
out_fail:
de_put(de);
goto out;
}
/***********************************************************************************************************/
void d_instantiate(struct dentry *entry, struct inode * inode)
{
printk("d_instantiate\n");
if (!list_empty(&entry->d_alias)) BUG();
spin_lock(&dcache_lock);
if (inode)
list_add(&entry->d_alias, &inode->i_dentry);
entry->d_inode = inode;
spin_unlock(&dcache_lock);
}
struct dentry * d_alloc_root(struct inode * root_inode)
{
struct dentry *res = NULL;
printk("d_alloc_root\n");
if (root_inode) {
res = d_alloc(NULL, &(const struct qstr) { "/", 1, 0 });
if (res) {
res->d_sb = root_inode->i_sb;
res->d_parent = res;
d_instantiate(res, root_inode);
}
}
return res;
}
void force_delete(struct inode *inode)
{
printk("force_delete\n");
struct hello_dir_entry *de = inode->u.generic_ip;
if (atomic_read(&inode->i_count) == 1)
inode->i_nlink = 0;
if (atomic_dec_and_test(&de->count))
printk("hello_root.count: %d\n", atomic_read(&de->count));
}
static void hello_delete_inode(struct inode *inode)
{
printk("hello_delete_inode\n");
struct hello_dir_entry *de = inode->u.generic_ip;
inode->i_state = I_CLEAR;
/*if (de) {
if (de->owner)
__MOD_DEC_USE_COUNT(de->owner);
de_put(de);
}*/
}
static void hello_read_inode(struct inode * inode)
{
printk("hello_read_inode\n");
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
}
static int hello_statfs(struct super_block *sb, struct statfs *buf)
{
printk("hello_statfs\n");
return 0;
}
void hello_write_super(struct super_block *s)
{
printk("write_super\n");
}
static struct super_operations hello_sops = {
read_inode: hello_read_inode,
put_inode: force_delete,
delete_inode: hello_delete_inode,
write_super: hello_write_super,
/*statfs: hello_statfs,*/
};
struct dentry_operations hello_dops = {
/*d_revalidate: hello_d_revalidate,
d_hash: hello_d_hash,
d_compare: hello_d_compare,*/
/*d_delete: hello_d_delete,*/
d_release: hello_d_release,
/*d_iput: hello_d_iput*/
};
struct super_block *hello_read_super(struct super_block *s, void *data,
int silent)
{
printk("hello_read_super\n");
struct inode * root_inode;
s->s_blocksize = 1024;
s->s_blocksize_bits = 10;
s->s_magic = 0;
s->s_op = &hello_sops;
root_inode = hello_get_inode(s, HELLO_ROOT_INO, &hello_root);
if (!root_inode)
goto out_no_root;
s->s_root = d_alloc_root(root_inode);
if (!s->s_root)
goto out_no_root;
s->s_root->d_op = &hello_dops;
return s;
out_no_root:
printk("hello_read_super: get root inode failed\n");
iput(root_inode);
return NULL;
}
[/code:1]
hello.h
[code:1]
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/wrapper.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/poll.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#define HELLO_ROOT_INO 1
typedef int (read_hello_t)(char *page, char **start, off_t off,
int count, int *eof, void *data);
typedef int (write_hello_t)(struct file *file, const char *buffer,
unsigned long count, void *data);
typedef int (get_info_t)(char *, char **, off_t, int);
struct hello_dir_entry {
unsigned short low_ino;
unsigned short namelen;
const char *name;
mode_t mode;
nlink_t nlink;
user_id_t uid;
gid_t gid;
unsigned long size;
struct inode_operations * hello_iops;
struct file_operations * hello_fops;
get_info_t *get_info;
struct module *owner;
struct hello_dir_entry *next, *parent, *subdir;
void *data;
read_hello_t *read_hello;
write_hello_t *write_hello;
atomic_t count; /* use count */
int deleted; /* delete flag */
kdev_t rdev;
};
extern struct hello_dir_entry hello_root;
extern struct dentry *hello_lookup(struct inode *, struct dentry *);
extern int hello_misc_init(void);
extern struct super_block *hello_read_super(struct super_block *, void *, int);
extern void de_put(struct hello_dir_entry *);
extern struct hello_dir_entry * de_get(struct hello_dir_entry *);
extern int hello_readdir(struct file *, void *, filldir_t);
[/code:1]
hello_entry.c
[code:1]
#include "hello.h"
static struct inode_operations hello_dir_inode_operations = {
lookup: hello_lookup,
};
struct hello_dir_entry * de_get(struct hello_dir_entry *de)
{
printk("de_get\n");
if (de)
atomic_inc(&de->count);
return de;
}
void inline free_hello_entry(struct hello_dir_entry *de)
{
printk("free_hello_entry\n");
kfree(de);
}
void de_put(struct hello_dir_entry *de)
{
printk("de_put\n");
if (de) {
if (!atomic_read(&de->count)) {
printk("de_put: entry %s already free!\n", de->name);
return;
}
if (atomic_dec_and_test(&de->count))
free_hello_entry(de);
}
}
static ssize_t
hello_file_read(struct file * file, char * buf, size_t nbytes, loff_t *ppos)
{
struct inode * inode = file->f_dentry->d_inode;
char *page;
ssize_t n;
char *start;
struct hello_dir_entry * dp;
dp = (struct hello_dir_entry *) inode->u.generic_ip;
if (!(page = (char*) __get_free_page(GFP_KERNEL)))
return -ENOMEM;
n = dp->read_hello(page, &start, *ppos,0, NULL, NULL);
copy_to_user(buf, page, n);
free_page((unsigned long) page);
return n;
}
static ssize_t
hello_file_write(struct file * file, const char * buffer,
size_t count, loff_t *ppos)
{
struct inode *inode = file->f_dentry->d_inode;
struct hello_dir_entry * dp;
dp = (struct hello_dir_entry *) inode->u.generic_ip;
if (!dp->write_hello)
return -EIO;
/* FIXME: does this routine need ppos? probably... */
return dp->write_hello(file, buffer, count, dp->data);
}
static loff_t
hello_file_lseek(struct file * file, loff_t offset, int origin)
{
long long retval;
switch (origin) {
case 2:
offset += file->f_dentry->d_inode->i_size;
break;
case 1:
offset += file->f_pos;
}
retval = -EINVAL;
if (offset>=0 && offset<=file->f_dentry->d_inode->i_sb->s_maxbytes) {
if (offset != file->f_pos) {
file->f_pos = offset;
file->f_reada = 0;
}
retval = offset;
}
return retval;
}
static struct file_operations hello_file_operations = {
llseek: hello_file_lseek,
read: hello_file_read,
write: hello_file_write,
};
static int hello_register(struct hello_dir_entry * dir, struct hello_dir_entry * dp)
{
printk("hello_register\n");
dp->low_ino = 2;
dp->next = dir->subdir;
dp->parent = dir;
dir->subdir = dp;
if (S_ISDIR(dp->mode)) {
if (dp->hello_iops == NULL) {
dp->hello_fops = NULL;
dp->hello_iops = &hello_dir_inode_operations;
}
dir->nlink++;
} else if (S_ISREG(dp->mode)) {
if (dp->hello_fops == NULL)
dp->hello_fops = &hello_file_operations;
}
return 0;
}
static struct hello_dir_entry *hello_create(struct hello_dir_entry **parent,
const char *name,
mode_t mode,
nlink_t nlink)
{
printk("hello_create\n");
struct hello_dir_entry *ent = NULL;
const char *fn = name;
int len;
len = strlen(name);
*parent = &hello_root;
ent = kmalloc(sizeof(struct hello_dir_entry) + len + 1, GFP_KERNEL);
if (!ent) goto out;
memset(ent, 0, sizeof(struct hello_dir_entry));
memcpy(((char *) ent) + sizeof(struct hello_dir_entry), fn, len + 1);
ent->name = ((char *) ent) + sizeof(*ent);
ent->namelen = len;
ent->mode = mode;
ent->nlink = nlink;
out:
return ent;
}
struct hello_dir_entry *create_hello_entry(const char *name, mode_t mode,
struct hello_dir_entry *parent)
{
printk("create_hello_entry\n");
struct hello_dir_entry *ent;
nlink_t nlink;
if (S_ISDIR(mode)) {
if ((mode & S_IALLUGO) == 0)
mode |= S_IRUGO | S_IXUGO;
nlink = 2;
} else {
if ((mode & S_IFMT) == 0)
mode |= S_IFREG;
if ((mode & S_IALLUGO) == 0)
mode |= S_IRUGO;
nlink = 1;
}
ent = hello_create(&parent,name,mode,nlink);
if (ent) {
if (hello_register(parent, ent) < 0) {
kfree(ent);
ent = NULL;
}
}
return ent;
}
static inline struct hello_dir_entry *hello_read_entry(const char *name,
mode_t mode, struct hello_dir_entry *base,
read_hello_t *read_hello, void * data)
{
printk("hello_dir_entry\n");
struct hello_dir_entry *res=create_hello_entry(name,mode,base);
if (res) {
res->read_hello=read_hello;
res->write_hello = NULL;
res->data=data;
}
return res;
}
/************************************************************************************************************/
int read_hello(char *page, char **start, off_t off, int count, int *eof, void *data)
{
strcpy(page, "hello world!");
return 13;
}
int hello_misc_init(void)
{
printk("hello_misc_init\n");
struct hello_dir_entry *err;
err = hello_read_entry("zhang", 0, NULL, read_hello, NULL);
return !err;
}
[/code:1]
mount.c
[code:1]
#include "hello.h"
extern int graft_tree(struct vfsmount *, struct nameidata *);
static DECLARE_FSTYPE(hello_fs_type, "hello", hello_read_super, FS_SINGLE);
struct vfsmount *mnt;
int hello_root_init(void)
{
struct nameidata nd;
int err;
err = register_filesystem(&hello_fs_type);
printk("register_filesystem\n");
if (err)
return err;
mnt = kern_mount(&hello_fs_type);
printk("kern_mount\n");
err = PTR_ERR(mnt);
if (IS_ERR(mnt))
goto out;
hello_misc_init();
MOD_DEC_USE_COUNT;
/* int (*path_lookup)(const char *, unsigned, struct nameidata *) = (void*)0xc0152ac0;
int (*path_init)(const char *, unsigned int, struct nameidata *) = (void*)0xc0152b00;
int (*path_walk)(const char *, struct nameidata *) = (void*)0xc0152940;
char * name;
int (*graft_tree)(struct vfsmount *mnt, struct nameidata *nd) = (void*)0xc015fc30;
name = kmalloc(10, GFP_KERNEL);
strcpy(name, "/hello");
err = path_lookup(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd);
kfree(name);
if (path_init("/hello", LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd))
err = path_walk("/hello", &nd);
if (err)
goto out;
err = graft_tree(mnt, &nd);
*/
char *name, *type;
name = kmalloc(10, GFP_KERNEL);
type = kmalloc(10, GFP_KERNEL);
strcpy(name, "/hello");
strcpy(type, "hello");
long (*do_mount)(char *, char *, char *, unsigned long, void *) = (void*)0xc01603f0;/*0xc0166ad0;*/
do_mount(NULL, name, type, 0, NULL);
kfree(name);
kfree(type);
/*if (err)
goto out;
*/
return 0;
out:
mntput(mnt);
unregister_filesystem(&hello_fs_type);
return err;
}
int init_module(void)
{
printk("init_module\n");
hello_root_init();
return 0;
}
void cleanup_module()
{
printk("cleanup_module\n");
mntput(mnt);
unregister_filesystem(&hello_fs_type);
}
[/code:1]
Makefile
[code:1]
CC = gcc
CFLAGS = -O -Wall -D__KERNEL__ -DMODULE
#INCLUDEDIR = /usr/local/linux-2.4.22/include
INCLUDEDIR = /usr/src/linux-2.4.20-8/include
CFLAGS += -I$(INCLUDEDIR)
myfs.o: mount.o hello_entry.o hello.o
$(LD) -m elf_i386 -r -o myfs.o mount.o hello_entry.o hello.o
mount.o: mount.c hello.h /usr/include/linux/version.h
$(CC) $(CFLAGS) -c mount.c
hello_entry.o: hello_entry.c hello.h /usr/include/linux/version.h
$(CC) $(CFLAGS) -c hello_entry.c
hello.o: hello.c hello.h /usr/include/linux/version.h
$(CC) $(CFLAGS) -c hello.c
[/code:1]
测试程序read.c
[code:1]
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
int main()
{
int fp;
char buf[11];
buf[10] = 0;
int i;
if ((fp = open("/hello/zhang", O_RDWR)) == 0) {
printf("Could not opened!\n");
return -1;
}
else
printf("File open ok!\n");
read(fp, buf, 13);
printf("%s\n", buf);
close(fp);
}
[/code:1] |
|
IP卡
狗仔卡
发表于 2004-5-25 19:34:06
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
显身卡