+++ /dev/null
-/*****************************************************************************/
-
-/*
- * inode.c -- Inode/Dentry functions for the USB device file system.
- *
- * Copyright (C) 2000 Thomas Sailer (sailer@ife.ee.ethz.ch)
- * Copyright (C) 2001,2002,2004 Greg Kroah-Hartman (greg@kroah.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * History:
- * 0.1 04.01.2000 Created
- * 0.2 10.12.2001 converted to use the vfs layer better
- */
-
-/*****************************************************************************/
-
-#include <linux/module.h>
-#include <linux/fs.h>
-#include <linux/mount.h>
-#include <linux/pagemap.h>
-#include <linux/init.h>
-#include <linux/proc_fs.h>
-#include <linux/usb.h>
-#include <linux/namei.h>
-#include <linux/usbdevice_fs.h>
-#include <linux/parser.h>
-#include <linux/notifier.h>
-#include <linux/seq_file.h>
-#include <linux/usb/hcd.h>
-#include <asm/byteorder.h>
-#include "usb.h"
-
-#define USBFS_DEFAULT_DEVMODE (S_IWUSR | S_IRUGO)
-#define USBFS_DEFAULT_BUSMODE (S_IXUGO | S_IRUGO)
-#define USBFS_DEFAULT_LISTMODE S_IRUGO
-
-static const struct file_operations default_file_operations;
-static struct vfsmount *usbfs_mount;
-static int usbfs_mount_count; /* = 0 */
-
-static struct dentry *devices_usbfs_dentry;
-static int num_buses; /* = 0 */
-
-static uid_t devuid; /* = 0 */
-static uid_t busuid; /* = 0 */
-static uid_t listuid; /* = 0 */
-static gid_t devgid; /* = 0 */
-static gid_t busgid; /* = 0 */
-static gid_t listgid; /* = 0 */
-static umode_t devmode = USBFS_DEFAULT_DEVMODE;
-static umode_t busmode = USBFS_DEFAULT_BUSMODE;
-static umode_t listmode = USBFS_DEFAULT_LISTMODE;
-
-static int usbfs_show_options(struct seq_file *seq, struct dentry *root)
-{
- if (devuid != 0)
- seq_printf(seq, ",devuid=%u", devuid);
- if (devgid != 0)
- seq_printf(seq, ",devgid=%u", devgid);
- if (devmode != USBFS_DEFAULT_DEVMODE)
- seq_printf(seq, ",devmode=%o", devmode);
- if (busuid != 0)
- seq_printf(seq, ",busuid=%u", busuid);
- if (busgid != 0)
- seq_printf(seq, ",busgid=%u", busgid);
- if (busmode != USBFS_DEFAULT_BUSMODE)
- seq_printf(seq, ",busmode=%o", busmode);
- if (listuid != 0)
- seq_printf(seq, ",listuid=%u", listuid);
- if (listgid != 0)
- seq_printf(seq, ",listgid=%u", listgid);
- if (listmode != USBFS_DEFAULT_LISTMODE)
- seq_printf(seq, ",listmode=%o", listmode);
-
- return 0;
-}
-
-enum {
- Opt_devuid, Opt_devgid, Opt_devmode,
- Opt_busuid, Opt_busgid, Opt_busmode,
- Opt_listuid, Opt_listgid, Opt_listmode,
- Opt_err,
-};
-
-static const match_table_t tokens = {
- {Opt_devuid, "devuid=%u"},
- {Opt_devgid, "devgid=%u"},
- {Opt_devmode, "devmode=%o"},
- {Opt_busuid, "busuid=%u"},
- {Opt_busgid, "busgid=%u"},
- {Opt_busmode, "busmode=%o"},
- {Opt_listuid, "listuid=%u"},
- {Opt_listgid, "listgid=%u"},
- {Opt_listmode, "listmode=%o"},
- {Opt_err, NULL}
-};
-
-static int parse_options(struct super_block *s, char *data)
-{
- char *p;
- int option;
-
- /* (re)set to defaults. */
- devuid = 0;
- busuid = 0;
- listuid = 0;
- devgid = 0;
- busgid = 0;
- listgid = 0;
- devmode = USBFS_DEFAULT_DEVMODE;
- busmode = USBFS_DEFAULT_BUSMODE;
- listmode = USBFS_DEFAULT_LISTMODE;
-
- while ((p = strsep(&data, ",")) != NULL) {
- substring_t args[MAX_OPT_ARGS];
- int token;
- if (!*p)
- continue;
-
- token = match_token(p, tokens, args);
- switch (token) {
- case Opt_devuid:
- if (match_int(&args[0], &option))
- return -EINVAL;
- devuid = option;
- break;
- case Opt_devgid:
- if (match_int(&args[0], &option))
- return -EINVAL;
- devgid = option;
- break;
- case Opt_devmode:
- if (match_octal(&args[0], &option))
- return -EINVAL;
- devmode = option & S_IRWXUGO;
- break;
- case Opt_busuid:
- if (match_int(&args[0], &option))
- return -EINVAL;
- busuid = option;
- break;
- case Opt_busgid:
- if (match_int(&args[0], &option))
- return -EINVAL;
- busgid = option;
- break;
- case Opt_busmode:
- if (match_octal(&args[0], &option))
- return -EINVAL;
- busmode = option & S_IRWXUGO;
- break;
- case Opt_listuid:
- if (match_int(&args[0], &option))
- return -EINVAL;
- listuid = option;
- break;
- case Opt_listgid:
- if (match_int(&args[0], &option))
- return -EINVAL;
- listgid = option;
- break;
- case Opt_listmode:
- if (match_octal(&args[0], &option))
- return -EINVAL;
- listmode = option & S_IRWXUGO;
- break;
- default:
- printk(KERN_ERR "usbfs: unrecognised mount option "
- "\"%s\" or missing value\n", p);
- return -EINVAL;
- }
- }
-
- return 0;
-}
-
-static void update_special(struct dentry *special)
-{
- special->d_inode->i_uid = listuid;
- special->d_inode->i_gid = listgid;
- special->d_inode->i_mode = S_IFREG | listmode;
-}
-
-static void update_dev(struct dentry *dev)
-{
- dev->d_inode->i_uid = devuid;
- dev->d_inode->i_gid = devgid;
- dev->d_inode->i_mode = S_IFREG | devmode;
-}
-
-static void update_bus(struct dentry *bus)
-{
- struct dentry *dev = NULL;
-
- bus->d_inode->i_uid = busuid;
- bus->d_inode->i_gid = busgid;
- bus->d_inode->i_mode = S_IFDIR | busmode;
-
- mutex_lock(&bus->d_inode->i_mutex);
-
- list_for_each_entry(dev, &bus->d_subdirs, d_u.d_child)
- if (dev->d_inode)
- update_dev(dev);
-
- mutex_unlock(&bus->d_inode->i_mutex);
-}
-
-static void update_sb(struct super_block *sb)
-{
- struct dentry *root = sb->s_root;
- struct dentry *bus = NULL;
-
- if (!root)
- return;
-
- mutex_lock_nested(&root->d_inode->i_mutex, I_MUTEX_PARENT);
-
- list_for_each_entry(bus, &root->d_subdirs, d_u.d_child) {
- if (bus->d_inode) {
- switch (S_IFMT & bus->d_inode->i_mode) {
- case S_IFDIR:
- update_bus(bus);
- break;
- case S_IFREG:
- update_special(bus);
- break;
- default:
- printk(KERN_WARNING "usbfs: Unknown node %s "
- "mode %x found on remount!\n",
- bus->d_name.name, bus->d_inode->i_mode);
- break;
- }
- }
- }
-
- mutex_unlock(&root->d_inode->i_mutex);
-}
-
-static int remount(struct super_block *sb, int *flags, char *data)
-{
- /* If this is not a real mount,
- * i.e. it's a simple_pin_fs from create_special_files,
- * then ignore it.
- */
- if (*flags & MS_KERNMOUNT)
- return 0;
-
- if (parse_options(sb, data)) {
- printk(KERN_WARNING "usbfs: mount parameter error.\n");
- return -EINVAL;
- }
-
- if (usbfs_mount)
- update_sb(usbfs_mount->mnt_sb);
-
- return 0;
-}
-
-static struct inode *usbfs_get_inode (struct super_block *sb, umode_t mode, dev_t dev)
-{
- struct inode *inode = new_inode(sb);
-
- if (inode) {
- inode->i_ino = get_next_ino();
- inode_init_owner(inode, NULL, mode);
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- switch (mode & S_IFMT) {
- default:
- init_special_inode(inode, mode, dev);
- break;
- case S_IFREG:
- inode->i_fop = &default_file_operations;
- break;
- case S_IFDIR:
- inode->i_op = &simple_dir_inode_operations;
- inode->i_fop = &simple_dir_operations;
-
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inc_nlink(inode);
- break;
- }
- }
- return inode;
-}
-
-/* SMP-safe */
-static int usbfs_mknod (struct inode *dir, struct dentry *dentry, umode_t mode,
- dev_t dev)
-{
- struct inode *inode = usbfs_get_inode(dir->i_sb, mode, dev);
- int error = -EPERM;
-
- if (dentry->d_inode)
- return -EEXIST;
-
- if (inode) {
- d_instantiate(dentry, inode);
- dget(dentry);
- error = 0;
- }
- return error;
-}
-
-static int usbfs_mkdir (struct inode *dir, struct dentry *dentry, umode_t mode)
-{
- int res;
-
- mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR;
- res = usbfs_mknod (dir, dentry, mode, 0);
- if (!res)
- inc_nlink(dir);
- return res;
-}
-
-static int usbfs_create (struct inode *dir, struct dentry *dentry, umode_t mode)
-{
- mode = (mode & S_IALLUGO) | S_IFREG;
- return usbfs_mknod (dir, dentry, mode, 0);
-}
-
-static inline int usbfs_positive (struct dentry *dentry)
-{
- return dentry->d_inode && !d_unhashed(dentry);
-}
-
-static int usbfs_empty (struct dentry *dentry)
-{
- struct list_head *list;
-
- spin_lock(&dentry->d_lock);
- list_for_each(list, &dentry->d_subdirs) {
- struct dentry *de = list_entry(list, struct dentry, d_u.d_child);
-
- spin_lock_nested(&de->d_lock, DENTRY_D_LOCK_NESTED);
- if (usbfs_positive(de)) {
- spin_unlock(&de->d_lock);
- spin_unlock(&dentry->d_lock);
- return 0;
- }
- spin_unlock(&de->d_lock);
- }
- spin_unlock(&dentry->d_lock);
- return 1;
-}
-
-static int usbfs_unlink (struct inode *dir, struct dentry *dentry)
-{
- struct inode *inode = dentry->d_inode;
- mutex_lock(&inode->i_mutex);
- drop_nlink(dentry->d_inode);
- dput(dentry);
- mutex_unlock(&inode->i_mutex);
- d_delete(dentry);
- return 0;
-}
-
-static int usbfs_rmdir(struct inode *dir, struct dentry *dentry)
-{
- int error = -ENOTEMPTY;
- struct inode * inode = dentry->d_inode;
-
- mutex_lock(&inode->i_mutex);
- dentry_unhash(dentry);
- if (usbfs_empty(dentry)) {
- dont_mount(dentry);
- drop_nlink(dentry->d_inode);
- drop_nlink(dentry->d_inode);
- dput(dentry);
- inode->i_flags |= S_DEAD;
- drop_nlink(dir);
- error = 0;
- }
- mutex_unlock(&inode->i_mutex);
- if (!error)
- d_delete(dentry);
- return error;
-}
-
-
-/* default file operations */
-static ssize_t default_read_file (struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- return 0;
-}
-
-static ssize_t default_write_file (struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- return count;
-}
-
-static loff_t default_file_lseek (struct file *file, loff_t offset, int orig)
-{
- loff_t retval = -EINVAL;
-
- mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
- switch(orig) {
- case 0:
- if (offset > 0) {
- file->f_pos = offset;
- retval = file->f_pos;
- }
- break;
- case 1:
- if ((offset + file->f_pos) > 0) {
- file->f_pos += offset;
- retval = file->f_pos;
- }
- break;
- default:
- break;
- }
- mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
- return retval;
-}
-
-static const struct file_operations default_file_operations = {
- .read = default_read_file,
- .write = default_write_file,
- .open = simple_open,
- .llseek = default_file_lseek,
-};
-
-static const struct super_operations usbfs_ops = {
- .statfs = simple_statfs,
- .drop_inode = generic_delete_inode,
- .remount_fs = remount,
- .show_options = usbfs_show_options,
-};
-
-static int usbfs_fill_super(struct super_block *sb, void *data, int silent)
-{
- struct inode *inode;
-
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
- sb->s_magic = USBDEVICE_SUPER_MAGIC;
- sb->s_op = &usbfs_ops;
- sb->s_time_gran = 1;
- inode = usbfs_get_inode(sb, S_IFDIR | 0755, 0);
- sb->s_root = d_make_root(inode);
- if (!sb->s_root) {
- dbg("%s: could not get root dentry!",__func__);
- return -ENOMEM;
- }
- return 0;
-}
-
-/*
- * fs_create_by_name - create a file, given a name
- * @name: name of file
- * @mode: type of file
- * @parent: dentry of directory to create it in
- * @dentry: resulting dentry of file
- *
- * This function handles both regular files and directories.
- */
-static int fs_create_by_name (const char *name, umode_t mode,
- struct dentry *parent, struct dentry **dentry)
-{
- int error = 0;
-
- /* If the parent is not specified, we create it in the root.
- * We need the root dentry to do this, which is in the super
- * block. A pointer to that is in the struct vfsmount that we
- * have around.
- */
- if (!parent ) {
- if (usbfs_mount)
- parent = usbfs_mount->mnt_root;
- }
-
- if (!parent) {
- dbg("Ah! can not find a parent!");
- return -EFAULT;
- }
-
- *dentry = NULL;
- mutex_lock(&parent->d_inode->i_mutex);
- *dentry = lookup_one_len(name, parent, strlen(name));
- if (!IS_ERR(*dentry)) {
- if (S_ISDIR(mode))
- error = usbfs_mkdir (parent->d_inode, *dentry, mode);
- else
- error = usbfs_create (parent->d_inode, *dentry, mode);
- } else
- error = PTR_ERR(*dentry);
- mutex_unlock(&parent->d_inode->i_mutex);
-
- return error;
-}
-
-static struct dentry *fs_create_file (const char *name, umode_t mode,
- struct dentry *parent, void *data,
- const struct file_operations *fops,
- uid_t uid, gid_t gid)
-{
- struct dentry *dentry;
- int error;
-
- dbg("creating file '%s'",name);
-
- error = fs_create_by_name (name, mode, parent, &dentry);
- if (error) {
- dentry = NULL;
- } else {
- if (dentry->d_inode) {
- if (data)
- dentry->d_inode->i_private = data;
- if (fops)
- dentry->d_inode->i_fop = fops;
- dentry->d_inode->i_uid = uid;
- dentry->d_inode->i_gid = gid;
- }
- }
-
- return dentry;
-}
-
-static void fs_remove_file (struct dentry *dentry)
-{
- struct dentry *parent = dentry->d_parent;
-
- if (!parent || !parent->d_inode)
- return;
-
- mutex_lock_nested(&parent->d_inode->i_mutex, I_MUTEX_PARENT);
- if (usbfs_positive(dentry)) {
- if (dentry->d_inode) {
- if (S_ISDIR(dentry->d_inode->i_mode))
- usbfs_rmdir(parent->d_inode, dentry);
- else
- usbfs_unlink(parent->d_inode, dentry);
- dput(dentry);
- }
- }
- mutex_unlock(&parent->d_inode->i_mutex);
-}
-
-/* --------------------------------------------------------------------- */
-
-static struct dentry *usb_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
-{
- return mount_single(fs_type, flags, data, usbfs_fill_super);
-}
-
-static struct file_system_type usb_fs_type = {
- .owner = THIS_MODULE,
- .name = "usbfs",
- .mount = usb_mount,
- .kill_sb = kill_litter_super,
-};
-
-/* --------------------------------------------------------------------- */
-
-static int create_special_files (void)
-{
- struct dentry *parent;
- int retval;
-
- /* create the devices special file */
- retval = simple_pin_fs(&usb_fs_type, &usbfs_mount, &usbfs_mount_count);
- if (retval) {
- printk(KERN_ERR "Unable to get usbfs mount\n");
- goto exit;
- }
-
- parent = usbfs_mount->mnt_root;
- devices_usbfs_dentry = fs_create_file ("devices",
- listmode | S_IFREG, parent,
- NULL, &usbfs_devices_fops,
- listuid, listgid);
- if (devices_usbfs_dentry == NULL) {
- printk(KERN_ERR "Unable to create devices usbfs file\n");
- retval = -ENODEV;
- goto error_clean_mounts;
- }
-
- goto exit;
-
-error_clean_mounts:
- simple_release_fs(&usbfs_mount, &usbfs_mount_count);
-exit:
- return retval;
-}
-
-static void remove_special_files (void)
-{
- if (devices_usbfs_dentry)
- fs_remove_file (devices_usbfs_dentry);
- devices_usbfs_dentry = NULL;
- simple_release_fs(&usbfs_mount, &usbfs_mount_count);
-}
-
-void usbfs_update_special (void)
-{
- struct inode *inode;
-
- if (devices_usbfs_dentry) {
- inode = devices_usbfs_dentry->d_inode;
- if (inode)
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- }
-}
-
-static void usbfs_add_bus(struct usb_bus *bus)
-{
- struct dentry *parent;
- char name[8];
- int retval;
-
- /* create the special files if this is the first bus added */
- if (num_buses == 0) {
- retval = create_special_files();
- if (retval)
- return;
- }
- ++num_buses;
-
- sprintf (name, "%03d", bus->busnum);
-
- parent = usbfs_mount->mnt_root;
- bus->usbfs_dentry = fs_create_file (name, busmode | S_IFDIR, parent,
- bus, NULL, busuid, busgid);
- if (bus->usbfs_dentry == NULL) {
- printk(KERN_ERR "Error creating usbfs bus entry\n");
- return;
- }
-}
-
-static void usbfs_remove_bus(struct usb_bus *bus)
-{
- if (bus->usbfs_dentry) {
- fs_remove_file (bus->usbfs_dentry);
- bus->usbfs_dentry = NULL;
- }
-
- --num_buses;
- if (num_buses <= 0) {
- remove_special_files();
- num_buses = 0;
- }
-}
-
-static void usbfs_add_device(struct usb_device *dev)
-{
- char name[8];
- int i;
- int i_size;
-
- sprintf (name, "%03d", dev->devnum);
- dev->usbfs_dentry = fs_create_file (name, devmode | S_IFREG,
- dev->bus->usbfs_dentry, dev,
- &usbdev_file_operations,
- devuid, devgid);
- if (dev->usbfs_dentry == NULL) {
- printk(KERN_ERR "Error creating usbfs device entry\n");
- return;
- }
-
- /* Set the size of the device's file to be
- * equal to the size of the device descriptors. */
- i_size = sizeof (struct usb_device_descriptor);
- for (i = 0; i < dev->descriptor.bNumConfigurations; ++i) {
- struct usb_config_descriptor *config =
- (struct usb_config_descriptor *)dev->rawdescriptors[i];
- i_size += le16_to_cpu(config->wTotalLength);
- }
- if (dev->usbfs_dentry->d_inode)
- dev->usbfs_dentry->d_inode->i_size = i_size;
-}
-
-static void usbfs_remove_device(struct usb_device *dev)
-{
- if (dev->usbfs_dentry) {
- fs_remove_file (dev->usbfs_dentry);
- dev->usbfs_dentry = NULL;
- }
-}
-
-static int usbfs_notify(struct notifier_block *self, unsigned long action, void *dev)
-{
- switch (action) {
- case USB_DEVICE_ADD:
- usbfs_add_device(dev);
- break;
- case USB_DEVICE_REMOVE:
- usbfs_remove_device(dev);
- break;
- case USB_BUS_ADD:
- usbfs_add_bus(dev);
- break;
- case USB_BUS_REMOVE:
- usbfs_remove_bus(dev);
- }
-
- usbfs_update_special();
- usbfs_conn_disc_event();
- return NOTIFY_OK;
-}
-
-static struct notifier_block usbfs_nb = {
- .notifier_call = usbfs_notify,
-};
-
-/* --------------------------------------------------------------------- */
-
-static struct proc_dir_entry *usbdir = NULL;
-
-int __init usbfs_init(void)
-{
- int retval;
-
- retval = register_filesystem(&usb_fs_type);
- if (retval)
- return retval;
-
- usb_register_notify(&usbfs_nb);
-
- /* create mount point for usbfs */
- usbdir = proc_mkdir("bus/usb", NULL);
-
- return 0;
-}
-
-void usbfs_cleanup(void)
-{
- usb_unregister_notify(&usbfs_nb);
- unregister_filesystem(&usb_fs_type);
- if (usbdir)
- remove_proc_entry("bus/usb", NULL);
-}
-
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff