diff options
Diffstat (limited to 'drivers/isdn/capi/capifs.c')
| -rw-r--r-- | drivers/isdn/capi/capifs.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/isdn/capi/capifs.c b/drivers/isdn/capi/capifs.c new file mode 100644 index 0000000..550e80f --- /dev/null +++ b/drivers/isdn/capi/capifs.c @@ -0,0 +1,223 @@ +/* $Id: capifs.c,v 1.1.2.3 2004/01/16 21:09:26 keil Exp $ + * + * Copyright 2000 by Carsten Paeth <calle@calle.de> + * + * Heavily based on devpts filesystem from H. Peter Anvin + * + * This software may be used and distributed according to the terms + * of the GNU General Public License, incorporated herein by reference. + * + */ + +#include <linux/fs.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/ctype.h> +#include <linux/sched.h> /* current */ + +#include "capifs.h" + +MODULE_DESCRIPTION("CAPI4Linux: /dev/capi/ filesystem"); +MODULE_AUTHOR("Carsten Paeth"); +MODULE_LICENSE("GPL"); + +/* ------------------------------------------------------------------ */ + +static char *revision = "$Revision: 1.1.2.3 $"; + +/* ------------------------------------------------------------------ */ + +#define CAPIFS_SUPER_MAGIC (('C'<<8)|'N') + +static struct vfsmount *capifs_mnt; +static struct dentry *capifs_root; + +static struct { + int setuid; + int setgid; + uid_t uid; + gid_t gid; + umode_t mode; +} config = {.mode = 0600}; + +/* ------------------------------------------------------------------ */ + +static int capifs_remount(struct super_block *s, int *flags, char *data) +{ + int setuid = 0; + int setgid = 0; + uid_t uid = 0; + gid_t gid = 0; + umode_t mode = 0600; + char *this_char; + char *new_opt = kstrdup(data, GFP_KERNEL); + + this_char = NULL; + while ((this_char = strsep(&data, ",")) != NULL) { + int n; + char dummy; + if (!*this_char) + continue; + if (sscanf(this_char, "uid=%i%c", &n, &dummy) == 1) { + setuid = 1; + uid = n; + } else if (sscanf(this_char, "gid=%i%c", &n, &dummy) == 1) { + setgid = 1; + gid = n; + } else if (sscanf(this_char, "mode=%o%c", &n, &dummy) == 1) + mode = n & ~S_IFMT; + else { + kfree(new_opt); + printk("capifs: called with bogus options\n"); + return -EINVAL; + } + } + + kfree(s->s_options); + s->s_options = new_opt; + + config.setuid = setuid; + config.setgid = setgid; + config.uid = uid; + config.gid = gid; + config.mode = mode; + + return 0; +} + +static struct super_operations capifs_sops = +{ + .statfs = simple_statfs, + .remount_fs = capifs_remount, + .show_options = generic_show_options, +}; + + +static int +capifs_fill_super(struct super_block *s, void *data, int silent) +{ + struct inode * inode; + + s->s_blocksize = 1024; + s->s_blocksize_bits = 10; + s->s_magic = CAPIFS_SUPER_MAGIC; + s->s_op = &capifs_sops; + s->s_time_gran = 1; + + inode = new_inode(s); + if (!inode) + goto fail; + inode->i_ino = 1; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + inode->i_blocks = 0; + inode->i_uid = inode->i_gid = 0; + inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR; + inode->i_op = &simple_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + inode->i_nlink = 2; + + capifs_root = s->s_root = d_alloc_root(inode); + if (s->s_root) + return 0; + + printk("capifs: get root dentry failed\n"); + iput(inode); +fail: + return -ENOMEM; +} + +static int capifs_get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data, struct vfsmount *mnt) +{ + return get_sb_single(fs_type, flags, data, capifs_fill_super, mnt); +} + +static struct file_system_type capifs_fs_type = { + .owner = THIS_MODULE, + .name = "capifs", + .get_sb = capifs_get_sb, + .kill_sb = kill_anon_super, +}; + +static struct dentry *get_node(int num) +{ + char s[10]; + struct dentry *root = capifs_root; + mutex_lock(&root->d_inode->i_mutex); + return lookup_one_len(s, root, sprintf(s, "%d", num)); +} + +void capifs_new_ncci(unsigned int number, dev_t device) +{ + struct dentry *dentry; + struct inode *inode = new_inode(capifs_mnt->mnt_sb); + if (!inode) + return; + inode->i_ino = number+2; + inode->i_uid = config.setuid ? config.uid : current->fsuid; + inode->i_gid = config.setgid ? config.gid : current->fsgid; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + init_special_inode(inode, S_IFCHR|config.mode, device); + //inode->i_op = &capifs_file_inode_operations; + + dentry = get_node(number); + if (!IS_ERR(dentry) && !dentry->d_inode) + d_instantiate(dentry, inode); + mutex_unlock(&capifs_root->d_inode->i_mutex); +} + +void capifs_free_ncci(unsigned int number) +{ + struct dentry *dentry = get_node(number); + + if (!IS_ERR(dentry)) { + struct inode *inode = dentry->d_inode; + if (inode) { + inode->i_nlink--; + d_delete(dentry); + dput(dentry); + } + dput(dentry); + } + mutex_unlock(&capifs_root->d_inode->i_mutex); +} + +static int __init capifs_init(void) +{ + char rev[32]; + char *p; + int err; + + if ((p = strchr(revision, ':')) != NULL && p[1]) { + strlcpy(rev, p + 2, sizeof(rev)); + if ((p = strchr(rev, '$')) != NULL && p > rev) + *(p-1) = 0; + } else + strcpy(rev, "1.0"); + + err = register_filesystem(&capifs_fs_type); + if (!err) { + capifs_mnt = kern_mount(&capifs_fs_type); + if (IS_ERR(capifs_mnt)) { + err = PTR_ERR(capifs_mnt); + unregister_filesystem(&capifs_fs_type); + } + } + if (!err) + printk(KERN_NOTICE "capifs: Rev %s\n", rev); + return err; +} + +static void __exit capifs_exit(void) +{ + unregister_filesystem(&capifs_fs_type); + mntput(capifs_mnt); +} + +EXPORT_SYMBOL(capifs_new_ncci); +EXPORT_SYMBOL(capifs_free_ncci); + +module_init(capifs_init); +module_exit(capifs_exit); |
