Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 *  linux/fs/proc/root.c

 *

 *  Copyright (C) 1991, 1992 Linus Torvalds

 *

 *  proc root directory handling functions

 */

#include <asm/uaccess.h>

#include <linux/errno.h>

#include <linux/time.h>

#include <linux/proc_fs.h>

#include <linux/stat.h>

#include <linux/init.h>

#include <linux/sched.h>

#include <linux/module.h>

#include <linux/bitops.h>

#include <linux/smp_lock.h>

#include <linux/mount.h>

#include <linux/pid_namespace.h>

#include "internal.h"

struct proc_dir_entry *proc_bus, *proc_root_fs, *proc_root_driver;

static int proc_test_super(struct super_block *sb, void *data)

{

        return sb->s_fs_info == data;

}

static int proc_set_super(struct super_block *sb, void *data)

{

        struct pid_namespace *ns;

        ns = (struct pid_namespace *)data;

        sb->s_fs_info = get_pid_ns(ns);

        return set_anon_super(sb, NULL);

}

static int proc_get_sb(struct file_system_type *fs_type,

        int flags, const char *dev_name, void *data, struct vfsmount *mnt)

{

        int err;

        struct super_block *sb;

        struct pid_namespace *ns;

        struct proc_inode *ei;

        if (proc_mnt) {

                /* Seed the root directory with a pid so it doesn't need

                 * to be special in base.c.  I would do this earlier but

                 * the only task alive when /proc is mounted the first time

                 * is the init_task and it doesn't have any pids.

                 */

                ei = PROC_I(proc_mnt->mnt_sb->s_root->d_inode);

                if (!ei->pid)

                        ei->pid = find_get_pid(1);

        }

        if (flags & MS_KERNMOUNT)

                ns = (struct pid_namespace *)data;

        else

                ns = current->nsproxy->pid_ns;

        sb = sget(fs_type, proc_test_super, proc_set_super, ns);

        if (IS_ERR(sb))

                return PTR_ERR(sb);

        if (!sb->s_root) {

                sb->s_flags = flags;

                err = proc_fill_super(sb);

                if (err) {

                        up_write(&sb->s_umount);

                        deactivate_super(sb);

                        return err;

                }

                ei = PROC_I(sb->s_root->d_inode);

                if (!ei->pid) {

                        rcu_read_lock();

                        ei->pid = get_pid(find_pid_ns(1, ns));

                        rcu_read_unlock();

                }

                sb->s_flags |= MS_ACTIVE;

                ns->proc_mnt = mnt;

        }

        return simple_set_mnt(mnt, sb);

}

static void proc_kill_sb(struct super_block *sb)

{

        struct pid_namespace *ns;

        ns = (struct pid_namespace *)sb->s_fs_info;

        kill_anon_super(sb);

        put_pid_ns(ns);

}

static struct file_system_type proc_fs_type = {

        .name           = "proc",

        .get_sb         = proc_get_sb,

        .kill_sb        = proc_kill_sb,

};

void __init proc_root_init(void)

{

        int err = proc_init_inodecache();

        if (err)

                return;

        err = register_filesystem(&proc_fs_type);

        if (err)

                return;

        proc_mnt = kern_mount_data(&proc_fs_type, &init_pid_ns);

        err = PTR_ERR(proc_mnt);

        if (IS_ERR(proc_mnt)) {

                unregister_filesystem(&proc_fs_type);

                return;

        }

        proc_misc_init();

        proc_net_init();

#ifdef CONFIG_SYSVIPC

        proc_mkdir("sysvipc", NULL);

#endif

        proc_root_fs = proc_mkdir("fs", NULL);

        proc_root_driver = proc_mkdir("driver", NULL);

        proc_mkdir("fs/nfsd", NULL); /* somewhere for the nfsd filesystem to be mounted */

#if defined(CONFIG_SUN_OPENPROMFS) || defined(CONFIG_SUN_OPENPROMFS_MODULE)

        /* just give it a mountpoint */

        proc_mkdir("openprom", NULL);

#endif

        proc_tty_init();

#ifdef CONFIG_PROC_DEVICETREE

        proc_device_tree_init();

#endif

        proc_bus = proc_mkdir("bus", NULL);

        proc_sys_init();

}

static int proc_root_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat

)

{

        generic_fillattr(dentry->d_inode, stat);

        stat->nlink = proc_root.nlink + nr_processes();

        return 0;

}

static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, struct nameidata *nd)

{

        if (!proc_lookup(dir, dentry, nd)) {

                return NULL;

        }

        return proc_pid_lookup(dir, dentry, nd);

}

static int proc_root_readdir(struct file * filp,

        void * dirent, filldir_t filldir)

{

        unsigned int nr = filp->f_pos;

        int ret;

        lock_kernel();

        if (nr < FIRST_PROCESS_ENTRY) {

                int error = proc_readdir(filp, dirent, filldir);

                if (error <= 0) {

                        unlock_kernel();

                        return error;

                }

                filp->f_pos = FIRST_PROCESS_ENTRY;

        }

        unlock_kernel();

        ret = proc_pid_readdir(filp, dirent, filldir);

        return ret;

}

/*

 * The root /proc directory is special, as it has the

 * <pid> directories. Thus we don't use the generic

 * directory handling functions for that..

 */

static const struct file_operations proc_root_operations = {

        .read            = generic_read_dir,

        .readdir         = proc_root_readdir,

};

/*

 * proc root can do almost nothing..

 */

static const struct inode_operations proc_root_inode_operations = {

        .lookup         = proc_root_lookup,

        .getattr        = proc_root_getattr,

};

/*

 * This is the root "inode" in the /proc tree..

 */

struct proc_dir_entry proc_root = {

        .low_ino        = PROC_ROOT_INO,

        .namelen        = 5,

        .name           = "/proc",

        .mode           = S_IFDIR | S_IRUGO | S_IXUGO,

        .nlink          = 2,

        .count          = ATOMIC_INIT(1),

        .proc_iops      = &proc_root_inode_operations,

        .proc_fops      = &proc_root_operations,

        .parent         = &proc_root,

};

int pid_ns_prepare_proc(struct pid_namespace *ns)

{

        struct vfsmount *mnt;

        mnt = kern_mount_data(&proc_fs_type, ns);

        if (IS_ERR(mnt))

                return PTR_ERR(mnt);

        return 0;

}

void pid_ns_release_proc(struct pid_namespace *ns)

{

        mntput(ns->proc_mnt);

}

EXPORT_SYMBOL(proc_symlink);

EXPORT_SYMBOL(proc_mkdir);

EXPORT_SYMBOL(create_proc_entry);

EXPORT_SYMBOL(remove_proc_entry);

EXPORT_SYMBOL(proc_root);

EXPORT_SYMBOL(proc_root_fs);

EXPORT_SYMBOL(proc_bus);

EXPORT_SYMBOL(proc_root_driver);