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/*
FUSE: Filesystem in Userspace
Copyright (C) 2001 Miklos Szeredi (mszeredi@inf.bme.hu)
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
#include "fuse_i.h"
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/file.h>
#define FUSE_SUPER_MAGIC 0x65735546
static void fuse_read_inode(struct inode *inode)
{
/* No op */
}
static void fuse_clear_inode(struct inode *inode)
{
struct fuse_conn *fc = INO_FC(inode);
struct fuse_in in = FUSE_IN_INIT;
struct fuse_forget_in arg;
arg.version = inode->i_version;
in.h.opcode = FUSE_FORGET;
in.h.ino = inode->i_ino;
in.argsize = sizeof(arg);
in.arg = &arg;
request_send(fc, &in, NULL);
}
static void fuse_put_super(struct super_block *sb)
{
struct fuse_conn *fc = sb->u.generic_sbp;
spin_lock(&fuse_lock);
fc->sb = NULL;
fc->uid = 0;
fc->flags = 0;
fuse_release_conn(fc);
spin_unlock(&fuse_lock);
}
static struct super_operations fuse_super_operations = {
read_inode: fuse_read_inode,
clear_inode: fuse_clear_inode,
put_super: fuse_put_super,
};
static struct fuse_conn *get_conn(struct fuse_mount_data *d)
{
struct fuse_conn *fc = NULL;
struct file *file;
struct inode *ino;
if(d == NULL) {
printk("fuse_read_super: Bad mount data\n");
return NULL;
}
if(d->version != FUSE_KERNEL_VERSION) {
printk("fuse_read_super: Bad version: %i\n", d->version);
return NULL;
}
file = fget(d->fd);
ino = NULL;
if(file)
ino = file->f_dentry->d_inode;
if(!ino || ino->u.generic_ip != proc_fuse_dev) {
printk("fuse_read_super: Bad file: %i\n", d->fd);
goto out;
}
fc = file->private_data;
out:
fput(file);
return fc;
}
static struct inode *get_root_inode(struct super_block *sb, unsigned int mode)
{
struct fuse_attr attr;
memset(&attr, 0, sizeof(attr));
attr.mode = mode;
return fuse_iget(sb, 1, &attr, 0);
}
static struct super_block *fuse_read_super(struct super_block *sb,
void *data, int silent)
{
struct fuse_conn *fc;
struct inode *root;
struct fuse_mount_data *d = data;
sb->s_blocksize = 1024;
sb->s_blocksize_bits = 10;
sb->s_magic = FUSE_SUPER_MAGIC;
sb->s_op = &fuse_super_operations;
root = get_root_inode(sb, d->rootmode);
if(root == NULL) {
printk("fuse_read_super: failed to get root inode\n");
return NULL;
}
spin_lock(&fuse_lock);
fc = get_conn(d);
if(fc == NULL)
goto err;
if(fc->sb != NULL) {
printk("fuse_read_super: connection already mounted\n");
goto err;
}
sb->u.generic_sbp = fc;
sb->s_root = d_alloc_root(root);
if(!sb->s_root)
goto err;
fc->sb = sb;
fc->flags = d->flags;
fc->uid = d->uid;
spin_unlock(&fuse_lock);
return sb;
err:
spin_unlock(&fuse_lock);
iput(root);
return NULL;
}
static DECLARE_FSTYPE(fuse_fs_type, "fuse", fuse_read_super, 0);
int fuse_fs_init()
{
int res;
res = register_filesystem(&fuse_fs_type);
if(res)
printk("fuse: failed to register filesystem\n");
return res;
}
void fuse_fs_cleanup()
{
unregister_filesystem(&fuse_fs_type);
}
/*
* Local Variables:
* indent-tabs-mode: t
* c-basic-offset: 8
* End: */
|
