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/*
 *  linux/fs/proc/base.c
 *
 *  Copyright (C) 1991, 1992 Linus Torvalds
 *
 *  proc base directory handling functions
 */

#include <asm/uaccess.h>

#include <linux/config.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/init.h>

static struct file_operations proc_base_operations = {
	NULL,			/* lseek - default */
	NULL,			/* read - bad */
	NULL,			/* write - bad */
	proc_readdir,		/* readdir */
	NULL,			/* poll - default */
	NULL,			/* ioctl - default */
	NULL,			/* mmap */
	NULL,			/* no special open code */
	NULL,			/* flush */
	NULL,			/* no special release code */
	NULL			/* can't fsync */
};

/*
 * proc directories can do almost nothing..
 */
static struct inode_operations proc_base_inode_operations = {
	&proc_base_operations,	/* default base directory file-ops */
	NULL,			/* create */
	proc_lookup,		/* lookup */
	NULL,			/* link */
	NULL,			/* unlink */
	NULL,			/* symlink */
	NULL,			/* mkdir */
	NULL,			/* rmdir */
	NULL,			/* mknod */
	NULL,			/* rename */
	NULL,			/* readlink */
	NULL,			/* follow_link */
	NULL,			/* readpage */
	NULL,			/* writepage */
	NULL,			/* bmap */
	NULL,			/* truncate */
	NULL			/* permission */
};

/*
 * The fill argument is non-zero when the inode is being filled ...
 * we don't need to do anything when it's being deleted.
 */
static void proc_pid_fill_inode(struct inode * inode, int fill)
{
	struct task_struct *p;
	int pid = inode->i_ino >> 16;
	int ino = inode->i_ino & 0xffff;

	read_lock(&tasklist_lock);
	if (fill && (p = find_task_by_pid(pid)) != NULL) {
		uid_t uid = 0;
		gid_t gid = 0;
		if (p->dumpable || ino == PROC_PID_INO) {
			uid = p->euid;
			gid = p->egid;
		}
		inode->i_uid = uid;
		inode->i_gid = gid;
	}
	read_unlock(&tasklist_lock);
}

/*
 * This is really a pseudo-entry, and only links
 * backwards to the parent with no link from the
 * root directory to this. This way we can have just
 * one entry for every /proc/<pid>/ directory.
 */
struct proc_dir_entry proc_pid = {
	PROC_PID_INO, 5, "<pid>",
	S_IFDIR | S_IRUGO | S_IXUGO, 2, 0, 0,
	0, &proc_base_inode_operations,
	NULL, proc_pid_fill_inode,
	NULL, &proc_root, NULL
};

static struct proc_dir_entry proc_pid_status = {
	PROC_PID_STATUS, 6, "status",
	S_IFREG | S_IRUGO, 1, 0, 0,
	0, &proc_array_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_mem = {
	PROC_PID_MEM, 3, "mem",
	S_IFREG | S_IRUSR | S_IWUSR, 1, 0, 0,
	0, &proc_mem_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_cwd = {
	PROC_PID_CWD, 3, "cwd",
	S_IFLNK | S_IRWXU, 1, 0, 0,
	0, &proc_link_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_root = {
	PROC_PID_ROOT, 4, "root",
	S_IFLNK | S_IRWXU, 1, 0, 0,
	0, &proc_link_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_exe = {
	PROC_PID_EXE, 3, "exe",
	S_IFLNK | S_IRWXU, 1, 0, 0,
	0, &proc_link_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_fd = {
	PROC_PID_FD, 2, "fd",
	S_IFDIR | S_IRUSR | S_IXUSR, 2, 0, 0,
	0, &proc_fd_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_environ = {
	PROC_PID_ENVIRON, 7, "environ",
	S_IFREG | S_IRUSR, 1, 0, 0,
	0, &proc_array_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_cmdline = {
	PROC_PID_CMDLINE, 7, "cmdline",
	S_IFREG | S_IRUGO, 1, 0, 0,
	0, &proc_array_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_stat = {
	PROC_PID_STAT, 4, "stat",
	S_IFREG | S_IRUGO, 1, 0, 0,
	0, &proc_array_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_statm = {
	PROC_PID_STATM, 5, "statm",
	S_IFREG | S_IRUGO, 1, 0, 0,
	0, &proc_array_inode_operations,
	NULL, proc_pid_fill_inode,
};
static struct proc_dir_entry proc_pid_maps = {
	PROC_PID_MAPS, 4, "maps",
	S_IFIFO | S_IRUGO, 1, 0, 0,
	0, &proc_arraylong_inode_operations,
	NULL, proc_pid_fill_inode,
};

#if CONFIG_AP1000
static struct proc_dir_entry proc_pid_ringbuf = {
	PROC_PID_RINGBUF, 7, "ringbuf",
	S_IFREG | S_IRUGO | S_IWUSR, 1, 0, 0,
	0, &proc_ringbuf_inode_operations,
	NULL, proc_pid_fill_inode,
};
#endif

#ifdef __SMP__
static struct proc_dir_entry proc_pid_cpu = {
	PROC_PID_CPU, 3, "cpu",
	S_IFREG | S_IRUGO, 1, 0, 0,
	0, &proc_array_inode_operations,
	NULL, proc_pid_fill_inode,
};
#endif

__initfunc(void proc_base_init(void))
{
#if CONFIG_AP1000
	proc_register(&proc_pid, &proc_pid_ringbuf);
#endif
	proc_register(&proc_pid, &proc_pid_status);
	proc_register(&proc_pid, &proc_pid_mem);
	proc_register(&proc_pid, &proc_pid_cwd);
	proc_register(&proc_pid, &proc_pid_root);
	proc_register(&proc_pid, &proc_pid_exe);
	proc_register(&proc_pid, &proc_pid_fd);
	proc_register(&proc_pid, &proc_pid_environ);
	proc_register(&proc_pid, &proc_pid_cmdline);
	proc_register(&proc_pid, &proc_pid_stat);
	proc_register(&proc_pid, &proc_pid_statm);
	proc_register(&proc_pid, &proc_pid_maps);
#ifdef __SMP__	
	proc_register(&proc_pid, &proc_pid_cpu);
#endif	
};