Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/fs/proc/base.c b/fs/proc/base.c
new file mode 100644
index 0000000..dad8ea4
--- /dev/null
+++ b/fs/proc/base.c
@@ -0,0 +1,2056 @@
+/*
+ *  linux/fs/proc/base.c
+ *
+ *  Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ *  proc base directory handling functions
+ *
+ *  1999, Al Viro. Rewritten. Now it covers the whole per-process part.
+ *  Instead of using magical inumbers to determine the kind of object
+ *  we allocate and fill in-core inodes upon lookup. They don't even
+ *  go into icache. We cache the reference to task_struct upon lookup too.
+ *  Eventually it should become a filesystem in its own. We don't use the
+ *  rest of procfs anymore.
+ */
+
+#include <asm/uaccess.h>
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/time.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/file.h>
+#include <linux/string.h>
+#include <linux/seq_file.h>
+#include <linux/namei.h>
+#include <linux/namespace.h>
+#include <linux/mm.h>
+#include <linux/smp_lock.h>
+#include <linux/kallsyms.h>
+#include <linux/mount.h>
+#include <linux/security.h>
+#include <linux/ptrace.h>
+#include <linux/seccomp.h>
+#include <linux/cpuset.h>
+#include <linux/audit.h>
+#include "internal.h"
+
+/*
+ * For hysterical raisins we keep the same inumbers as in the old procfs.
+ * Feel free to change the macro below - just keep the range distinct from
+ * inumbers of the rest of procfs (currently those are in 0x0000--0xffff).
+ * As soon as we'll get a separate superblock we will be able to forget
+ * about magical ranges too.
+ */
+
+#define fake_ino(pid,ino) (((pid)<<16)|(ino))
+
+enum pid_directory_inos {
+	PROC_TGID_INO = 2,
+	PROC_TGID_TASK,
+	PROC_TGID_STATUS,
+	PROC_TGID_MEM,
+#ifdef CONFIG_SECCOMP
+	PROC_TGID_SECCOMP,
+#endif
+	PROC_TGID_CWD,
+	PROC_TGID_ROOT,
+	PROC_TGID_EXE,
+	PROC_TGID_FD,
+	PROC_TGID_ENVIRON,
+	PROC_TGID_AUXV,
+	PROC_TGID_CMDLINE,
+	PROC_TGID_STAT,
+	PROC_TGID_STATM,
+	PROC_TGID_MAPS,
+	PROC_TGID_MOUNTS,
+	PROC_TGID_WCHAN,
+#ifdef CONFIG_SCHEDSTATS
+	PROC_TGID_SCHEDSTAT,
+#endif
+#ifdef CONFIG_CPUSETS
+	PROC_TGID_CPUSET,
+#endif
+#ifdef CONFIG_SECURITY
+	PROC_TGID_ATTR,
+	PROC_TGID_ATTR_CURRENT,
+	PROC_TGID_ATTR_PREV,
+	PROC_TGID_ATTR_EXEC,
+	PROC_TGID_ATTR_FSCREATE,
+#endif
+#ifdef CONFIG_AUDITSYSCALL
+	PROC_TGID_LOGINUID,
+#endif
+	PROC_TGID_FD_DIR,
+	PROC_TGID_OOM_SCORE,
+	PROC_TGID_OOM_ADJUST,
+	PROC_TID_INO,
+	PROC_TID_STATUS,
+	PROC_TID_MEM,
+#ifdef CONFIG_SECCOMP
+	PROC_TID_SECCOMP,
+#endif
+	PROC_TID_CWD,
+	PROC_TID_ROOT,
+	PROC_TID_EXE,
+	PROC_TID_FD,
+	PROC_TID_ENVIRON,
+	PROC_TID_AUXV,
+	PROC_TID_CMDLINE,
+	PROC_TID_STAT,
+	PROC_TID_STATM,
+	PROC_TID_MAPS,
+	PROC_TID_MOUNTS,
+	PROC_TID_WCHAN,
+#ifdef CONFIG_SCHEDSTATS
+	PROC_TID_SCHEDSTAT,
+#endif
+#ifdef CONFIG_CPUSETS
+	PROC_TID_CPUSET,
+#endif
+#ifdef CONFIG_SECURITY
+	PROC_TID_ATTR,
+	PROC_TID_ATTR_CURRENT,
+	PROC_TID_ATTR_PREV,
+	PROC_TID_ATTR_EXEC,
+	PROC_TID_ATTR_FSCREATE,
+#endif
+#ifdef CONFIG_AUDITSYSCALL
+	PROC_TID_LOGINUID,
+#endif
+	PROC_TID_FD_DIR = 0x8000,	/* 0x8000-0xffff */
+	PROC_TID_OOM_SCORE,
+	PROC_TID_OOM_ADJUST,
+};
+
+struct pid_entry {
+	int type;
+	int len;
+	char *name;
+	mode_t mode;
+};
+
+#define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)}
+
+static struct pid_entry tgid_base_stuff[] = {
+	E(PROC_TGID_TASK,      "task",    S_IFDIR|S_IRUGO|S_IXUGO),
+	E(PROC_TGID_FD,        "fd",      S_IFDIR|S_IRUSR|S_IXUSR),
+	E(PROC_TGID_ENVIRON,   "environ", S_IFREG|S_IRUSR),
+	E(PROC_TGID_AUXV,      "auxv",	  S_IFREG|S_IRUSR),
+	E(PROC_TGID_STATUS,    "status",  S_IFREG|S_IRUGO),
+	E(PROC_TGID_CMDLINE,   "cmdline", S_IFREG|S_IRUGO),
+	E(PROC_TGID_STAT,      "stat",    S_IFREG|S_IRUGO),
+	E(PROC_TGID_STATM,     "statm",   S_IFREG|S_IRUGO),
+	E(PROC_TGID_MAPS,      "maps",    S_IFREG|S_IRUGO),
+	E(PROC_TGID_MEM,       "mem",     S_IFREG|S_IRUSR|S_IWUSR),
+#ifdef CONFIG_SECCOMP
+	E(PROC_TGID_SECCOMP,   "seccomp", S_IFREG|S_IRUSR|S_IWUSR),
+#endif
+	E(PROC_TGID_CWD,       "cwd",     S_IFLNK|S_IRWXUGO),
+	E(PROC_TGID_ROOT,      "root",    S_IFLNK|S_IRWXUGO),
+	E(PROC_TGID_EXE,       "exe",     S_IFLNK|S_IRWXUGO),
+	E(PROC_TGID_MOUNTS,    "mounts",  S_IFREG|S_IRUGO),
+#ifdef CONFIG_SECURITY
+	E(PROC_TGID_ATTR,      "attr",    S_IFDIR|S_IRUGO|S_IXUGO),
+#endif
+#ifdef CONFIG_KALLSYMS
+	E(PROC_TGID_WCHAN,     "wchan",   S_IFREG|S_IRUGO),
+#endif
+#ifdef CONFIG_SCHEDSTATS
+	E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO),
+#endif
+#ifdef CONFIG_CPUSETS
+	E(PROC_TGID_CPUSET,    "cpuset",  S_IFREG|S_IRUGO),
+#endif
+	E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO),
+	E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR),
+#ifdef CONFIG_AUDITSYSCALL
+	E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO),
+#endif
+	{0,0,NULL,0}
+};
+static struct pid_entry tid_base_stuff[] = {
+	E(PROC_TID_FD,         "fd",      S_IFDIR|S_IRUSR|S_IXUSR),
+	E(PROC_TID_ENVIRON,    "environ", S_IFREG|S_IRUSR),
+	E(PROC_TID_AUXV,       "auxv",	  S_IFREG|S_IRUSR),
+	E(PROC_TID_STATUS,     "status",  S_IFREG|S_IRUGO),
+	E(PROC_TID_CMDLINE,    "cmdline", S_IFREG|S_IRUGO),
+	E(PROC_TID_STAT,       "stat",    S_IFREG|S_IRUGO),
+	E(PROC_TID_STATM,      "statm",   S_IFREG|S_IRUGO),
+	E(PROC_TID_MAPS,       "maps",    S_IFREG|S_IRUGO),
+	E(PROC_TID_MEM,        "mem",     S_IFREG|S_IRUSR|S_IWUSR),
+#ifdef CONFIG_SECCOMP
+	E(PROC_TID_SECCOMP,    "seccomp", S_IFREG|S_IRUSR|S_IWUSR),
+#endif
+	E(PROC_TID_CWD,        "cwd",     S_IFLNK|S_IRWXUGO),
+	E(PROC_TID_ROOT,       "root",    S_IFLNK|S_IRWXUGO),
+	E(PROC_TID_EXE,        "exe",     S_IFLNK|S_IRWXUGO),
+	E(PROC_TID_MOUNTS,     "mounts",  S_IFREG|S_IRUGO),
+#ifdef CONFIG_SECURITY
+	E(PROC_TID_ATTR,       "attr",    S_IFDIR|S_IRUGO|S_IXUGO),
+#endif
+#ifdef CONFIG_KALLSYMS
+	E(PROC_TID_WCHAN,      "wchan",   S_IFREG|S_IRUGO),
+#endif
+#ifdef CONFIG_SCHEDSTATS
+	E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO),
+#endif
+#ifdef CONFIG_CPUSETS
+	E(PROC_TID_CPUSET,     "cpuset",  S_IFREG|S_IRUGO),
+#endif
+	E(PROC_TID_OOM_SCORE,  "oom_score",S_IFREG|S_IRUGO),
+	E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR),
+#ifdef CONFIG_AUDITSYSCALL
+	E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO),
+#endif
+	{0,0,NULL,0}
+};
+
+#ifdef CONFIG_SECURITY
+static struct pid_entry tgid_attr_stuff[] = {
+	E(PROC_TGID_ATTR_CURRENT,  "current",  S_IFREG|S_IRUGO|S_IWUGO),
+	E(PROC_TGID_ATTR_PREV,     "prev",     S_IFREG|S_IRUGO),
+	E(PROC_TGID_ATTR_EXEC,     "exec",     S_IFREG|S_IRUGO|S_IWUGO),
+	E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
+	{0,0,NULL,0}
+};
+static struct pid_entry tid_attr_stuff[] = {
+	E(PROC_TID_ATTR_CURRENT,   "current",  S_IFREG|S_IRUGO|S_IWUGO),
+	E(PROC_TID_ATTR_PREV,      "prev",     S_IFREG|S_IRUGO),
+	E(PROC_TID_ATTR_EXEC,      "exec",     S_IFREG|S_IRUGO|S_IWUGO),
+	E(PROC_TID_ATTR_FSCREATE,  "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
+	{0,0,NULL,0}
+};
+#endif
+
+#undef E
+
+static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
+{
+	struct task_struct *task = proc_task(inode);
+	struct files_struct *files;
+	struct file *file;
+	int fd = proc_type(inode) - PROC_TID_FD_DIR;
+
+	files = get_files_struct(task);
+	if (files) {
+		spin_lock(&files->file_lock);
+		file = fcheck_files(files, fd);
+		if (file) {
+			*mnt = mntget(file->f_vfsmnt);
+			*dentry = dget(file->f_dentry);
+			spin_unlock(&files->file_lock);
+			put_files_struct(files);
+			return 0;
+		}
+		spin_unlock(&files->file_lock);
+		put_files_struct(files);
+	}
+	return -ENOENT;
+}
+
+static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
+{
+	struct fs_struct *fs;
+	int result = -ENOENT;
+	task_lock(proc_task(inode));
+	fs = proc_task(inode)->fs;
+	if(fs)
+		atomic_inc(&fs->count);
+	task_unlock(proc_task(inode));
+	if (fs) {
+		read_lock(&fs->lock);
+		*mnt = mntget(fs->pwdmnt);
+		*dentry = dget(fs->pwd);
+		read_unlock(&fs->lock);
+		result = 0;
+		put_fs_struct(fs);
+	}
+	return result;
+}
+
+static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
+{
+	struct fs_struct *fs;
+	int result = -ENOENT;
+	task_lock(proc_task(inode));
+	fs = proc_task(inode)->fs;
+	if(fs)
+		atomic_inc(&fs->count);
+	task_unlock(proc_task(inode));
+	if (fs) {
+		read_lock(&fs->lock);
+		*mnt = mntget(fs->rootmnt);
+		*dentry = dget(fs->root);
+		read_unlock(&fs->lock);
+		result = 0;
+		put_fs_struct(fs);
+	}
+	return result;
+}
+
+#define MAY_PTRACE(task) \
+	(task == current || \
+	(task->parent == current && \
+	(task->ptrace & PT_PTRACED) && \
+	 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
+	 security_ptrace(current,task) == 0))
+
+static int may_ptrace_attach(struct task_struct *task)
+{
+	int retval = 0;
+
+	task_lock(task);
+
+	if (!task->mm)
+		goto out;
+	if (((current->uid != task->euid) ||
+	     (current->uid != task->suid) ||
+	     (current->uid != task->uid) ||
+	     (current->gid != task->egid) ||
+	     (current->gid != task->sgid) ||
+	     (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE))
+		goto out;
+	rmb();
+	if (!task->mm->dumpable && !capable(CAP_SYS_PTRACE))
+		goto out;
+	if (security_ptrace(current, task))
+		goto out;
+
+	retval = 1;
+out:
+	task_unlock(task);
+	return retval;
+}
+
+static int proc_pid_environ(struct task_struct *task, char * buffer)
+{
+	int res = 0;
+	struct mm_struct *mm = get_task_mm(task);
+	if (mm) {
+		unsigned int len = mm->env_end - mm->env_start;
+		if (len > PAGE_SIZE)
+			len = PAGE_SIZE;
+		res = access_process_vm(task, mm->env_start, buffer, len, 0);
+		if (!may_ptrace_attach(task))
+			res = -ESRCH;
+		mmput(mm);
+	}
+	return res;
+}
+
+static int proc_pid_cmdline(struct task_struct *task, char * buffer)
+{
+	int res = 0;
+	unsigned int len;
+	struct mm_struct *mm = get_task_mm(task);
+	if (!mm)
+		goto out;
+	if (!mm->arg_end)
+		goto out_mm;	/* Shh! No looking before we're done */
+
+ 	len = mm->arg_end - mm->arg_start;
+ 
+	if (len > PAGE_SIZE)
+		len = PAGE_SIZE;
+ 
+	res = access_process_vm(task, mm->arg_start, buffer, len, 0);
+
+	// If the nul at the end of args has been overwritten, then
+	// assume application is using setproctitle(3).
+	if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
+		len = strnlen(buffer, res);
+		if (len < res) {
+		    res = len;
+		} else {
+			len = mm->env_end - mm->env_start;
+			if (len > PAGE_SIZE - res)
+				len = PAGE_SIZE - res;
+			res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
+			res = strnlen(buffer, res);
+		}
+	}
+out_mm:
+	mmput(mm);
+out:
+	return res;
+}
+
+static int proc_pid_auxv(struct task_struct *task, char *buffer)
+{
+	int res = 0;
+	struct mm_struct *mm = get_task_mm(task);
+	if (mm) {
+		unsigned int nwords = 0;
+		do
+			nwords += 2;
+		while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
+		res = nwords * sizeof(mm->saved_auxv[0]);
+		if (res > PAGE_SIZE)
+			res = PAGE_SIZE;
+		memcpy(buffer, mm->saved_auxv, res);
+		mmput(mm);
+	}
+	return res;
+}
+
+
+#ifdef CONFIG_KALLSYMS
+/*
+ * Provides a wchan file via kallsyms in a proper one-value-per-file format.
+ * Returns the resolved symbol.  If that fails, simply return the address.
+ */
+static int proc_pid_wchan(struct task_struct *task, char *buffer)
+{
+	char *modname;
+	const char *sym_name;
+	unsigned long wchan, size, offset;
+	char namebuf[KSYM_NAME_LEN+1];
+
+	wchan = get_wchan(task);
+
+	sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf);
+	if (sym_name)
+		return sprintf(buffer, "%s", sym_name);
+	return sprintf(buffer, "%lu", wchan);
+}
+#endif /* CONFIG_KALLSYMS */
+
+#ifdef CONFIG_SCHEDSTATS
+/*
+ * Provides /proc/PID/schedstat
+ */
+static int proc_pid_schedstat(struct task_struct *task, char *buffer)
+{
+	return sprintf(buffer, "%lu %lu %lu\n",
+			task->sched_info.cpu_time,
+			task->sched_info.run_delay,
+			task->sched_info.pcnt);
+}
+#endif
+
+/* The badness from the OOM killer */
+unsigned long badness(struct task_struct *p, unsigned long uptime);
+static int proc_oom_score(struct task_struct *task, char *buffer)
+{
+	unsigned long points;
+	struct timespec uptime;
+
+	do_posix_clock_monotonic_gettime(&uptime);
+	points = badness(task, uptime.tv_sec);
+	return sprintf(buffer, "%lu\n", points);
+}
+
+/************************************************************************/
+/*                       Here the fs part begins                        */
+/************************************************************************/
+
+/* permission checks */
+
+static int proc_check_root(struct inode *inode)
+{
+	struct dentry *de, *base, *root;
+	struct vfsmount *our_vfsmnt, *vfsmnt, *mnt;
+	int res = 0;
+
+	if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */
+		return -ENOENT;
+	read_lock(&current->fs->lock);
+	our_vfsmnt = mntget(current->fs->rootmnt);
+	base = dget(current->fs->root);
+	read_unlock(&current->fs->lock);
+
+	spin_lock(&vfsmount_lock);
+	de = root;
+	mnt = vfsmnt;
+
+	while (vfsmnt != our_vfsmnt) {
+		if (vfsmnt == vfsmnt->mnt_parent)
+			goto out;
+		de = vfsmnt->mnt_mountpoint;
+		vfsmnt = vfsmnt->mnt_parent;
+	}
+
+	if (!is_subdir(de, base))
+		goto out;
+	spin_unlock(&vfsmount_lock);
+
+exit:
+	dput(base);
+	mntput(our_vfsmnt);
+	dput(root);
+	mntput(mnt);
+	return res;
+out:
+	spin_unlock(&vfsmount_lock);
+	res = -EACCES;
+	goto exit;
+}
+
+static int proc_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+	if (generic_permission(inode, mask, NULL) != 0)
+		return -EACCES;
+	return proc_check_root(inode);
+}
+
+extern struct seq_operations proc_pid_maps_op;
+static int maps_open(struct inode *inode, struct file *file)
+{
+	struct task_struct *task = proc_task(inode);
+	int ret = seq_open(file, &proc_pid_maps_op);
+	if (!ret) {
+		struct seq_file *m = file->private_data;
+		m->private = task;
+	}
+	return ret;
+}
+
+static struct file_operations proc_maps_operations = {
+	.open		= maps_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
+extern struct seq_operations mounts_op;
+static int mounts_open(struct inode *inode, struct file *file)
+{
+	struct task_struct *task = proc_task(inode);
+	int ret = seq_open(file, &mounts_op);
+
+	if (!ret) {
+		struct seq_file *m = file->private_data;
+		struct namespace *namespace;
+		task_lock(task);
+		namespace = task->namespace;
+		if (namespace)
+			get_namespace(namespace);
+		task_unlock(task);
+
+		if (namespace)
+			m->private = namespace;
+		else {
+			seq_release(inode, file);
+			ret = -EINVAL;
+		}
+	}
+	return ret;
+}
+
+static int mounts_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *m = file->private_data;
+	struct namespace *namespace = m->private;
+	put_namespace(namespace);
+	return seq_release(inode, file);
+}
+
+static struct file_operations proc_mounts_operations = {
+	.open		= mounts_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= mounts_release,
+};
+
+#define PROC_BLOCK_SIZE	(3*1024)		/* 4K page size but our output routines use some slack for overruns */
+
+static ssize_t proc_info_read(struct file * file, char __user * buf,
+			  size_t count, loff_t *ppos)
+{
+	struct inode * inode = file->f_dentry->d_inode;
+	unsigned long page;
+	ssize_t length;
+	struct task_struct *task = proc_task(inode);
+
+	if (count > PROC_BLOCK_SIZE)
+		count = PROC_BLOCK_SIZE;
+	if (!(page = __get_free_page(GFP_KERNEL)))
+		return -ENOMEM;
+
+	length = PROC_I(inode)->op.proc_read(task, (char*)page);
+
+	if (length >= 0)
+		length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
+	free_page(page);
+	return length;
+}
+
+static struct file_operations proc_info_file_operations = {
+	.read		= proc_info_read,
+};
+
+static int mem_open(struct inode* inode, struct file* file)
+{
+	file->private_data = (void*)((long)current->self_exec_id);
+	return 0;
+}
+
+static ssize_t mem_read(struct file * file, char __user * buf,
+			size_t count, loff_t *ppos)
+{
+	struct task_struct *task = proc_task(file->f_dentry->d_inode);
+	char *page;
+	unsigned long src = *ppos;
+	int ret = -ESRCH;
+	struct mm_struct *mm;
+
+	if (!MAY_PTRACE(task) || !may_ptrace_attach(task))
+		goto out;
+
+	ret = -ENOMEM;
+	page = (char *)__get_free_page(GFP_USER);
+	if (!page)
+		goto out;
+
+	ret = 0;
+ 
+	mm = get_task_mm(task);
+	if (!mm)
+		goto out_free;
+
+	ret = -EIO;
+ 
+	if (file->private_data != (void*)((long)current->self_exec_id))
+		goto out_put;
+
+	ret = 0;
+ 
+	while (count > 0) {
+		int this_len, retval;
+
+		this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
+		retval = access_process_vm(task, src, page, this_len, 0);
+		if (!retval || !MAY_PTRACE(task) || !may_ptrace_attach(task)) {
+			if (!ret)
+				ret = -EIO;
+			break;
+		}
+
+		if (copy_to_user(buf, page, retval)) {
+			ret = -EFAULT;
+			break;
+		}
+ 
+		ret += retval;
+		src += retval;
+		buf += retval;
+		count -= retval;
+	}
+	*ppos = src;
+
+out_put:
+	mmput(mm);
+out_free:
+	free_page((unsigned long) page);
+out:
+	return ret;
+}
+
+#define mem_write NULL
+
+#ifndef mem_write
+/* This is a security hazard */
+static ssize_t mem_write(struct file * file, const char * buf,
+			 size_t count, loff_t *ppos)
+{
+	int copied = 0;
+	char *page;
+	struct task_struct *task = proc_task(file->f_dentry->d_inode);
+	unsigned long dst = *ppos;
+
+	if (!MAY_PTRACE(task) || !may_ptrace_attach(task))
+		return -ESRCH;
+
+	page = (char *)__get_free_page(GFP_USER);
+	if (!page)
+		return -ENOMEM;
+
+	while (count > 0) {
+		int this_len, retval;
+
+		this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
+		if (copy_from_user(page, buf, this_len)) {
+			copied = -EFAULT;
+			break;
+		}
+		retval = access_process_vm(task, dst, page, this_len, 1);
+		if (!retval) {
+			if (!copied)
+				copied = -EIO;
+			break;
+		}
+		copied += retval;
+		buf += retval;
+		dst += retval;
+		count -= retval;			
+	}
+	*ppos = dst;
+	free_page((unsigned long) page);
+	return copied;
+}
+#endif
+
+static loff_t mem_lseek(struct file * file, loff_t offset, int orig)
+{
+	switch (orig) {
+	case 0:
+		file->f_pos = offset;
+		break;
+	case 1:
+		file->f_pos += offset;
+		break;
+	default:
+		return -EINVAL;
+	}
+	force_successful_syscall_return();
+	return file->f_pos;
+}
+
+static struct file_operations proc_mem_operations = {
+	.llseek		= mem_lseek,
+	.read		= mem_read,
+	.write		= mem_write,
+	.open		= mem_open,
+};
+
+static ssize_t oom_adjust_read(struct file *file, char __user *buf,
+				size_t count, loff_t *ppos)
+{
+	struct task_struct *task = proc_task(file->f_dentry->d_inode);
+	char buffer[8];
+	size_t len;
+	int oom_adjust = task->oomkilladj;
+	loff_t __ppos = *ppos;
+
+	len = sprintf(buffer, "%i\n", oom_adjust);
+	if (__ppos >= len)
+		return 0;
+	if (count > len-__ppos)
+		count = len-__ppos;
+	if (copy_to_user(buf, buffer + __ppos, count))
+		return -EFAULT;
+	*ppos = __ppos + count;
+	return count;
+}
+
+static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
+				size_t count, loff_t *ppos)
+{
+	struct task_struct *task = proc_task(file->f_dentry->d_inode);
+	char buffer[8], *end;
+	int oom_adjust;
+
+	if (!capable(CAP_SYS_RESOURCE))
+		return -EPERM;
+	memset(buffer, 0, 8);
+	if (count > 6)
+		count = 6;
+	if (copy_from_user(buffer, buf, count))
+		return -EFAULT;
+	oom_adjust = simple_strtol(buffer, &end, 0);
+	if (oom_adjust < -16 || oom_adjust > 15)
+		return -EINVAL;
+	if (*end == '\n')
+		end++;
+	task->oomkilladj = oom_adjust;
+	if (end - buffer == 0)
+		return -EIO;
+	return end - buffer;
+}
+
+static struct file_operations proc_oom_adjust_operations = {
+	.read		= oom_adjust_read,
+	.write		= oom_adjust_write,
+};
+
+static struct inode_operations proc_mem_inode_operations = {
+	.permission	= proc_permission,
+};
+
+#ifdef CONFIG_AUDITSYSCALL
+#define TMPBUFLEN 21
+static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
+				  size_t count, loff_t *ppos)
+{
+	struct inode * inode = file->f_dentry->d_inode;
+	struct task_struct *task = proc_task(inode);
+	ssize_t length;
+	char tmpbuf[TMPBUFLEN];
+
+	length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
+				audit_get_loginuid(task->audit_context));
+	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
+}
+
+static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
+				   size_t count, loff_t *ppos)
+{
+	struct inode * inode = file->f_dentry->d_inode;
+	char *page, *tmp;
+	ssize_t length;
+	struct task_struct *task = proc_task(inode);
+	uid_t loginuid;
+
+	if (!capable(CAP_AUDIT_CONTROL))
+		return -EPERM;
+
+	if (current != task)
+		return -EPERM;
+
+	if (count > PAGE_SIZE)
+		count = PAGE_SIZE;
+
+	if (*ppos != 0) {
+		/* No partial writes. */
+		return -EINVAL;
+	}
+	page = (char*)__get_free_page(GFP_USER);
+	if (!page)
+		return -ENOMEM;
+	length = -EFAULT;
+	if (copy_from_user(page, buf, count))
+		goto out_free_page;
+
+	loginuid = simple_strtoul(page, &tmp, 10);
+	if (tmp == page) {
+		length = -EINVAL;
+		goto out_free_page;
+
+	}
+	length = audit_set_loginuid(task->audit_context, loginuid);
+	if (likely(length == 0))
+		length = count;
+
+out_free_page:
+	free_page((unsigned long) page);
+	return length;
+}
+
+static struct file_operations proc_loginuid_operations = {
+	.read		= proc_loginuid_read,
+	.write		= proc_loginuid_write,
+};
+#endif
+
+#ifdef CONFIG_SECCOMP
+static ssize_t seccomp_read(struct file *file, char __user *buf,
+			    size_t count, loff_t *ppos)
+{
+	struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
+	char __buf[20];
+	loff_t __ppos = *ppos;
+	size_t len;
+
+	/* no need to print the trailing zero, so use only len */
+	len = sprintf(__buf, "%u\n", tsk->seccomp.mode);
+	if (__ppos >= len)
+		return 0;
+	if (count > len - __ppos)
+		count = len - __ppos;
+	if (copy_to_user(buf, __buf + __ppos, count))
+		return -EFAULT;
+	*ppos = __ppos + count;
+	return count;
+}
+
+static ssize_t seccomp_write(struct file *file, const char __user *buf,
+			     size_t count, loff_t *ppos)
+{
+	struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
+	char __buf[20], *end;
+	unsigned int seccomp_mode;
+
+	/* can set it only once to be even more secure */
+	if (unlikely(tsk->seccomp.mode))
+		return -EPERM;
+
+	memset(__buf, 0, sizeof(__buf));
+	count = min(count, sizeof(__buf) - 1);
+	if (copy_from_user(__buf, buf, count))
+		return -EFAULT;
+	seccomp_mode = simple_strtoul(__buf, &end, 0);
+	if (*end == '\n')
+		end++;
+	if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) {
+		tsk->seccomp.mode = seccomp_mode;
+		set_tsk_thread_flag(tsk, TIF_SECCOMP);
+	} else
+		return -EINVAL;
+	if (unlikely(!(end - __buf)))
+		return -EIO;
+	return end - __buf;
+}
+
+static struct file_operations proc_seccomp_operations = {
+	.read		= seccomp_read,
+	.write		= seccomp_write,
+};
+#endif /* CONFIG_SECCOMP */
+
+static int proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = -EACCES;
+
+	/* We don't need a base pointer in the /proc filesystem */
+	path_release(nd);
+
+	if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
+		goto out;
+	error = proc_check_root(inode);
+	if (error)
+		goto out;
+
+	error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
+	nd->last_type = LAST_BIND;
+out:
+	return error;
+}
+
+static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
+			    char __user *buffer, int buflen)
+{
+	struct inode * inode;
+	char *tmp = (char*)__get_free_page(GFP_KERNEL), *path;
+	int len;
+
+	if (!tmp)
+		return -ENOMEM;
+		
+	inode = dentry->d_inode;
+	path = d_path(dentry, mnt, tmp, PAGE_SIZE);
+	len = PTR_ERR(path);
+	if (IS_ERR(path))
+		goto out;
+	len = tmp + PAGE_SIZE - 1 - path;
+
+	if (len > buflen)
+		len = buflen;
+	if (copy_to_user(buffer, path, len))
+		len = -EFAULT;
+ out:
+	free_page((unsigned long)tmp);
+	return len;
+}
+
+static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
+{
+	int error = -EACCES;
+	struct inode *inode = dentry->d_inode;
+	struct dentry *de;
+	struct vfsmount *mnt = NULL;
+
+	lock_kernel();
+
+	if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
+		goto out;
+	error = proc_check_root(inode);
+	if (error)
+		goto out;
+
+	error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
+	if (error)
+		goto out;
+
+	error = do_proc_readlink(de, mnt, buffer, buflen);
+	dput(de);
+	mntput(mnt);
+out:
+	unlock_kernel();
+	return error;
+}
+
+static struct inode_operations proc_pid_link_inode_operations = {
+	.readlink	= proc_pid_readlink,
+	.follow_link	= proc_pid_follow_link
+};
+
+#define NUMBUF 10
+
+static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct task_struct *p = proc_task(inode);
+	unsigned int fd, tid, ino;
+	int retval;
+	char buf[NUMBUF];
+	struct files_struct * files;
+
+	retval = -ENOENT;
+	if (!pid_alive(p))
+		goto out;
+	retval = 0;
+	tid = p->pid;
+
+	fd = filp->f_pos;
+	switch (fd) {
+		case 0:
+			if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
+				goto out;
+			filp->f_pos++;
+		case 1:
+			ino = fake_ino(tid, PROC_TID_INO);
+			if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
+				goto out;
+			filp->f_pos++;
+		default:
+			files = get_files_struct(p);
+			if (!files)
+				goto out;
+			spin_lock(&files->file_lock);
+			for (fd = filp->f_pos-2;
+			     fd < files->max_fds;
+			     fd++, filp->f_pos++) {
+				unsigned int i,j;
+
+				if (!fcheck_files(files, fd))
+					continue;
+				spin_unlock(&files->file_lock);
+
+				j = NUMBUF;
+				i = fd;
+				do {
+					j--;
+					buf[j] = '0' + (i % 10);
+					i /= 10;
+				} while (i);
+
+				ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
+				if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
+					spin_lock(&files->file_lock);
+					break;
+				}
+				spin_lock(&files->file_lock);
+			}
+			spin_unlock(&files->file_lock);
+			put_files_struct(files);
+	}
+out:
+	return retval;
+}
+
+static int proc_pident_readdir(struct file *filp,
+		void *dirent, filldir_t filldir,
+		struct pid_entry *ents, unsigned int nents)
+{
+	int i;
+	int pid;
+	struct dentry *dentry = filp->f_dentry;
+	struct inode *inode = dentry->d_inode;
+	struct pid_entry *p;
+	ino_t ino;
+	int ret;
+
+	ret = -ENOENT;
+	if (!pid_alive(proc_task(inode)))
+		goto out;
+
+	ret = 0;
+	pid = proc_task(inode)->pid;
+	i = filp->f_pos;
+	switch (i) {
+	case 0:
+		ino = inode->i_ino;
+		if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
+			goto out;
+		i++;
+		filp->f_pos++;
+		/* fall through */
+	case 1:
+		ino = parent_ino(dentry);
+		if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
+			goto out;
+		i++;
+		filp->f_pos++;
+		/* fall through */
+	default:
+		i -= 2;
+		if (i >= nents) {
+			ret = 1;
+			goto out;
+		}
+		p = ents + i;
+		while (p->name) {
+			if (filldir(dirent, p->name, p->len, filp->f_pos,
+				    fake_ino(pid, p->type), p->mode >> 12) < 0)
+				goto out;
+			filp->f_pos++;
+			p++;
+		}
+	}
+
+	ret = 1;
+out:
+	return ret;
+}
+
+static int proc_tgid_base_readdir(struct file * filp,
+			     void * dirent, filldir_t filldir)
+{
+	return proc_pident_readdir(filp,dirent,filldir,
+				   tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
+}
+
+static int proc_tid_base_readdir(struct file * filp,
+			     void * dirent, filldir_t filldir)
+{
+	return proc_pident_readdir(filp,dirent,filldir,
+				   tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
+}
+
+/* building an inode */
+
+static int task_dumpable(struct task_struct *task)
+{
+	int dumpable = 0;
+	struct mm_struct *mm;
+
+	task_lock(task);
+	mm = task->mm;
+	if (mm)
+		dumpable = mm->dumpable;
+	task_unlock(task);
+	return dumpable;
+}
+
+
+static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino)
+{
+	struct inode * inode;
+	struct proc_inode *ei;
+
+	/* We need a new inode */
+	
+	inode = new_inode(sb);
+	if (!inode)
+		goto out;
+
+	/* Common stuff */
+	ei = PROC_I(inode);
+	ei->task = NULL;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+	inode->i_ino = fake_ino(task->pid, ino);
+
+	if (!pid_alive(task))
+		goto out_unlock;
+
+	/*
+	 * grab the reference to task.
+	 */
+	get_task_struct(task);
+	ei->task = task;
+	ei->type = ino;
+	inode->i_uid = 0;
+	inode->i_gid = 0;
+	if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) {
+		inode->i_uid = task->euid;
+		inode->i_gid = task->egid;
+	}
+	security_task_to_inode(task, inode);
+
+out:
+	return inode;
+
+out_unlock:
+	ei->pde = NULL;
+	iput(inode);
+	return NULL;
+}
+
+/* dentry stuff */
+
+/*
+ *	Exceptional case: normally we are not allowed to unhash a busy
+ * directory. In this case, however, we can do it - no aliasing problems
+ * due to the way we treat inodes.
+ *
+ * Rewrite the inode's ownerships here because the owning task may have
+ * performed a setuid(), etc.
+ */
+static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+	struct inode *inode = dentry->d_inode;
+	struct task_struct *task = proc_task(inode);
+	if (pid_alive(task)) {
+		if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) {
+			inode->i_uid = task->euid;
+			inode->i_gid = task->egid;
+		} else {
+			inode->i_uid = 0;
+			inode->i_gid = 0;
+		}
+		security_task_to_inode(task, inode);
+		return 1;
+	}
+	d_drop(dentry);
+	return 0;
+}
+
+static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+	struct inode *inode = dentry->d_inode;
+	struct task_struct *task = proc_task(inode);
+	int fd = proc_type(inode) - PROC_TID_FD_DIR;
+	struct files_struct *files;
+
+	files = get_files_struct(task);
+	if (files) {
+		spin_lock(&files->file_lock);
+		if (fcheck_files(files, fd)) {
+			spin_unlock(&files->file_lock);
+			put_files_struct(files);
+			if (task_dumpable(task)) {
+				inode->i_uid = task->euid;
+				inode->i_gid = task->egid;
+			} else {
+				inode->i_uid = 0;
+				inode->i_gid = 0;
+			}
+			security_task_to_inode(task, inode);
+			return 1;
+		}
+		spin_unlock(&files->file_lock);
+		put_files_struct(files);
+	}
+	d_drop(dentry);
+	return 0;
+}
+
+static void pid_base_iput(struct dentry *dentry, struct inode *inode)
+{
+	struct task_struct *task = proc_task(inode);
+	spin_lock(&task->proc_lock);
+	if (task->proc_dentry == dentry)
+		task->proc_dentry = NULL;
+	spin_unlock(&task->proc_lock);
+	iput(inode);
+}
+
+static int pid_delete_dentry(struct dentry * dentry)
+{
+	/* Is the task we represent dead?
+	 * If so, then don't put the dentry on the lru list,
+	 * kill it immediately.
+	 */
+	return !pid_alive(proc_task(dentry->d_inode));
+}
+
+static struct dentry_operations tid_fd_dentry_operations =
+{
+	.d_revalidate	= tid_fd_revalidate,
+	.d_delete	= pid_delete_dentry,
+};
+
+static struct dentry_operations pid_dentry_operations =
+{
+	.d_revalidate	= pid_revalidate,
+	.d_delete	= pid_delete_dentry,
+};
+
+static struct dentry_operations pid_base_dentry_operations =
+{
+	.d_revalidate	= pid_revalidate,
+	.d_iput		= pid_base_iput,
+	.d_delete	= pid_delete_dentry,
+};
+
+/* Lookups */
+
+static unsigned name_to_int(struct dentry *dentry)
+{
+	const char *name = dentry->d_name.name;
+	int len = dentry->d_name.len;
+	unsigned n = 0;
+
+	if (len > 1 && *name == '0')
+		goto out;
+	while (len-- > 0) {
+		unsigned c = *name++ - '0';
+		if (c > 9)
+			goto out;
+		if (n >= (~0U-9)/10)
+			goto out;
+		n *= 10;
+		n += c;
+	}
+	return n;
+out:
+	return ~0U;
+}
+
+/* SMP-safe */
+static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
+{
+	struct task_struct *task = proc_task(dir);
+	unsigned fd = name_to_int(dentry);
+	struct file * file;
+	struct files_struct * files;
+	struct inode *inode;
+	struct proc_inode *ei;
+
+	if (fd == ~0U)
+		goto out;
+	if (!pid_alive(task))
+		goto out;
+
+	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd);
+	if (!inode)
+		goto out;
+	ei = PROC_I(inode);
+	files = get_files_struct(task);
+	if (!files)
+		goto out_unlock;
+	inode->i_mode = S_IFLNK;
+	spin_lock(&files->file_lock);
+	file = fcheck_files(files, fd);
+	if (!file)
+		goto out_unlock2;
+	if (file->f_mode & 1)
+		inode->i_mode |= S_IRUSR | S_IXUSR;
+	if (file->f_mode & 2)
+		inode->i_mode |= S_IWUSR | S_IXUSR;
+	spin_unlock(&files->file_lock);
+	put_files_struct(files);
+	inode->i_op = &proc_pid_link_inode_operations;
+	inode->i_size = 64;
+	ei->op.proc_get_link = proc_fd_link;
+	dentry->d_op = &tid_fd_dentry_operations;
+	d_add(dentry, inode);
+	return NULL;
+
+out_unlock2:
+	spin_unlock(&files->file_lock);
+	put_files_struct(files);
+out_unlock:
+	iput(inode);
+out:
+	return ERR_PTR(-ENOENT);
+}
+
+static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir);
+static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd);
+
+static struct file_operations proc_fd_operations = {
+	.read		= generic_read_dir,
+	.readdir	= proc_readfd,
+};
+
+static struct file_operations proc_task_operations = {
+	.read		= generic_read_dir,
+	.readdir	= proc_task_readdir,
+};
+
+/*
+ * proc directories can do almost nothing..
+ */
+static struct inode_operations proc_fd_inode_operations = {
+	.lookup		= proc_lookupfd,
+	.permission	= proc_permission,
+};
+
+static struct inode_operations proc_task_inode_operations = {
+	.lookup		= proc_task_lookup,
+	.permission	= proc_permission,
+};
+
+#ifdef CONFIG_SECURITY
+static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
+				  size_t count, loff_t *ppos)
+{
+	struct inode * inode = file->f_dentry->d_inode;
+	unsigned long page;
+	ssize_t length;
+	struct task_struct *task = proc_task(inode);
+
+	if (count > PAGE_SIZE)
+		count = PAGE_SIZE;
+	if (!(page = __get_free_page(GFP_KERNEL)))
+		return -ENOMEM;
+
+	length = security_getprocattr(task, 
+				      (char*)file->f_dentry->d_name.name, 
+				      (void*)page, count);
+	if (length >= 0)
+		length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
+	free_page(page);
+	return length;
+}
+
+static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
+				   size_t count, loff_t *ppos)
+{ 
+	struct inode * inode = file->f_dentry->d_inode;
+	char *page; 
+	ssize_t length; 
+	struct task_struct *task = proc_task(inode); 
+
+	if (count > PAGE_SIZE) 
+		count = PAGE_SIZE; 
+	if (*ppos != 0) {
+		/* No partial writes. */
+		return -EINVAL;
+	}
+	page = (char*)__get_free_page(GFP_USER); 
+	if (!page) 
+		return -ENOMEM;
+	length = -EFAULT; 
+	if (copy_from_user(page, buf, count)) 
+		goto out;
+
+	length = security_setprocattr(task, 
+				      (char*)file->f_dentry->d_name.name, 
+				      (void*)page, count);
+out:
+	free_page((unsigned long) page);
+	return length;
+} 
+
+static struct file_operations proc_pid_attr_operations = {
+	.read		= proc_pid_attr_read,
+	.write		= proc_pid_attr_write,
+};
+
+static struct file_operations proc_tid_attr_operations;
+static struct inode_operations proc_tid_attr_inode_operations;
+static struct file_operations proc_tgid_attr_operations;
+static struct inode_operations proc_tgid_attr_inode_operations;
+#endif
+
+/* SMP-safe */
+static struct dentry *proc_pident_lookup(struct inode *dir, 
+					 struct dentry *dentry,
+					 struct pid_entry *ents)
+{
+	struct inode *inode;
+	int error;
+	struct task_struct *task = proc_task(dir);
+	struct pid_entry *p;
+	struct proc_inode *ei;
+
+	error = -ENOENT;
+	inode = NULL;
+
+	if (!pid_alive(task))
+		goto out;
+
+	for (p = ents; p->name; p++) {
+		if (p->len != dentry->d_name.len)
+			continue;
+		if (!memcmp(dentry->d_name.name, p->name, p->len))
+			break;
+	}
+	if (!p->name)
+		goto out;
+
+	error = -EINVAL;
+	inode = proc_pid_make_inode(dir->i_sb, task, p->type);
+	if (!inode)
+		goto out;
+
+	ei = PROC_I(inode);
+	inode->i_mode = p->mode;
+	/*
+	 * Yes, it does not scale. And it should not. Don't add
+	 * new entries into /proc/<tgid>/ without very good reasons.
+	 */
+	switch(p->type) {
+		case PROC_TGID_TASK:
+			inode->i_nlink = 3;
+			inode->i_op = &proc_task_inode_operations;
+			inode->i_fop = &proc_task_operations;
+			break;
+		case PROC_TID_FD:
+		case PROC_TGID_FD:
+			inode->i_nlink = 2;
+			inode->i_op = &proc_fd_inode_operations;
+			inode->i_fop = &proc_fd_operations;
+			break;
+		case PROC_TID_EXE:
+		case PROC_TGID_EXE:
+			inode->i_op = &proc_pid_link_inode_operations;
+			ei->op.proc_get_link = proc_exe_link;
+			break;
+		case PROC_TID_CWD:
+		case PROC_TGID_CWD:
+			inode->i_op = &proc_pid_link_inode_operations;
+			ei->op.proc_get_link = proc_cwd_link;
+			break;
+		case PROC_TID_ROOT:
+		case PROC_TGID_ROOT:
+			inode->i_op = &proc_pid_link_inode_operations;
+			ei->op.proc_get_link = proc_root_link;
+			break;
+		case PROC_TID_ENVIRON:
+		case PROC_TGID_ENVIRON:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_environ;
+			break;
+		case PROC_TID_AUXV:
+		case PROC_TGID_AUXV:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_auxv;
+			break;
+		case PROC_TID_STATUS:
+		case PROC_TGID_STATUS:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_status;
+			break;
+		case PROC_TID_STAT:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_tid_stat;
+			break;
+		case PROC_TGID_STAT:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_tgid_stat;
+			break;
+		case PROC_TID_CMDLINE:
+		case PROC_TGID_CMDLINE:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_cmdline;
+			break;
+		case PROC_TID_STATM:
+		case PROC_TGID_STATM:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_statm;
+			break;
+		case PROC_TID_MAPS:
+		case PROC_TGID_MAPS:
+			inode->i_fop = &proc_maps_operations;
+			break;
+		case PROC_TID_MEM:
+		case PROC_TGID_MEM:
+			inode->i_op = &proc_mem_inode_operations;
+			inode->i_fop = &proc_mem_operations;
+			break;
+#ifdef CONFIG_SECCOMP
+		case PROC_TID_SECCOMP:
+		case PROC_TGID_SECCOMP:
+			inode->i_fop = &proc_seccomp_operations;
+			break;
+#endif /* CONFIG_SECCOMP */
+		case PROC_TID_MOUNTS:
+		case PROC_TGID_MOUNTS:
+			inode->i_fop = &proc_mounts_operations;
+			break;
+#ifdef CONFIG_SECURITY
+		case PROC_TID_ATTR:
+			inode->i_nlink = 2;
+			inode->i_op = &proc_tid_attr_inode_operations;
+			inode->i_fop = &proc_tid_attr_operations;
+			break;
+		case PROC_TGID_ATTR:
+			inode->i_nlink = 2;
+			inode->i_op = &proc_tgid_attr_inode_operations;
+			inode->i_fop = &proc_tgid_attr_operations;
+			break;
+		case PROC_TID_ATTR_CURRENT:
+		case PROC_TGID_ATTR_CURRENT:
+		case PROC_TID_ATTR_PREV:
+		case PROC_TGID_ATTR_PREV:
+		case PROC_TID_ATTR_EXEC:
+		case PROC_TGID_ATTR_EXEC:
+		case PROC_TID_ATTR_FSCREATE:
+		case PROC_TGID_ATTR_FSCREATE:
+			inode->i_fop = &proc_pid_attr_operations;
+			break;
+#endif
+#ifdef CONFIG_KALLSYMS
+		case PROC_TID_WCHAN:
+		case PROC_TGID_WCHAN:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_wchan;
+			break;
+#endif
+#ifdef CONFIG_SCHEDSTATS
+		case PROC_TID_SCHEDSTAT:
+		case PROC_TGID_SCHEDSTAT:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_pid_schedstat;
+			break;
+#endif
+#ifdef CONFIG_CPUSETS
+		case PROC_TID_CPUSET:
+		case PROC_TGID_CPUSET:
+			inode->i_fop = &proc_cpuset_operations;
+			break;
+#endif
+		case PROC_TID_OOM_SCORE:
+		case PROC_TGID_OOM_SCORE:
+			inode->i_fop = &proc_info_file_operations;
+			ei->op.proc_read = proc_oom_score;
+			break;
+		case PROC_TID_OOM_ADJUST:
+		case PROC_TGID_OOM_ADJUST:
+			inode->i_fop = &proc_oom_adjust_operations;
+			break;
+#ifdef CONFIG_AUDITSYSCALL
+		case PROC_TID_LOGINUID:
+		case PROC_TGID_LOGINUID:
+			inode->i_fop = &proc_loginuid_operations;
+			break;
+#endif
+		default:
+			printk("procfs: impossible type (%d)",p->type);
+			iput(inode);
+			return ERR_PTR(-EINVAL);
+	}
+	dentry->d_op = &pid_dentry_operations;
+	d_add(dentry, inode);
+	return NULL;
+
+out:
+	return ERR_PTR(error);
+}
+
+static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
+	return proc_pident_lookup(dir, dentry, tgid_base_stuff);
+}
+
+static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
+	return proc_pident_lookup(dir, dentry, tid_base_stuff);
+}
+
+static struct file_operations proc_tgid_base_operations = {
+	.read		= generic_read_dir,
+	.readdir	= proc_tgid_base_readdir,
+};
+
+static struct file_operations proc_tid_base_operations = {
+	.read		= generic_read_dir,
+	.readdir	= proc_tid_base_readdir,
+};
+
+static struct inode_operations proc_tgid_base_inode_operations = {
+	.lookup		= proc_tgid_base_lookup,
+};
+
+static struct inode_operations proc_tid_base_inode_operations = {
+	.lookup		= proc_tid_base_lookup,
+};
+
+#ifdef CONFIG_SECURITY
+static int proc_tgid_attr_readdir(struct file * filp,
+			     void * dirent, filldir_t filldir)
+{
+	return proc_pident_readdir(filp,dirent,filldir,
+				   tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff));
+}
+
+static int proc_tid_attr_readdir(struct file * filp,
+			     void * dirent, filldir_t filldir)
+{
+	return proc_pident_readdir(filp,dirent,filldir,
+				   tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff));
+}
+
+static struct file_operations proc_tgid_attr_operations = {
+	.read		= generic_read_dir,
+	.readdir	= proc_tgid_attr_readdir,
+};
+
+static struct file_operations proc_tid_attr_operations = {
+	.read		= generic_read_dir,
+	.readdir	= proc_tid_attr_readdir,
+};
+
+static struct dentry *proc_tgid_attr_lookup(struct inode *dir,
+				struct dentry *dentry, struct nameidata *nd)
+{
+	return proc_pident_lookup(dir, dentry, tgid_attr_stuff);
+}
+
+static struct dentry *proc_tid_attr_lookup(struct inode *dir,
+				struct dentry *dentry, struct nameidata *nd)
+{
+	return proc_pident_lookup(dir, dentry, tid_attr_stuff);
+}
+
+static struct inode_operations proc_tgid_attr_inode_operations = {
+	.lookup		= proc_tgid_attr_lookup,
+};
+
+static struct inode_operations proc_tid_attr_inode_operations = {
+	.lookup		= proc_tid_attr_lookup,
+};
+#endif
+
+/*
+ * /proc/self:
+ */
+static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
+			      int buflen)
+{
+	char tmp[30];
+	sprintf(tmp, "%d", current->tgid);
+	return vfs_readlink(dentry,buffer,buflen,tmp);
+}
+
+static int proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	char tmp[30];
+	sprintf(tmp, "%d", current->tgid);
+	return vfs_follow_link(nd,tmp);
+}	
+
+static struct inode_operations proc_self_inode_operations = {
+	.readlink	= proc_self_readlink,
+	.follow_link	= proc_self_follow_link,
+};
+
+/**
+ * proc_pid_unhash -  Unhash /proc/<pid> entry from the dcache.
+ * @p: task that should be flushed.
+ *
+ * Drops the /proc/<pid> dcache entry from the hash chains.
+ *
+ * Dropping /proc/<pid> entries and detach_pid must be synchroneous,
+ * otherwise e.g. /proc/<pid>/exe might point to the wrong executable,
+ * if the pid value is immediately reused. This is enforced by
+ * - caller must acquire spin_lock(p->proc_lock)
+ * - must be called before detach_pid()
+ * - proc_pid_lookup acquires proc_lock, and checks that
+ *   the target is not dead by looking at the attach count
+ *   of PIDTYPE_PID.
+ */
+
+struct dentry *proc_pid_unhash(struct task_struct *p)
+{
+	struct dentry *proc_dentry;
+
+	proc_dentry = p->proc_dentry;
+	if (proc_dentry != NULL) {
+
+		spin_lock(&dcache_lock);
+		spin_lock(&proc_dentry->d_lock);
+		if (!d_unhashed(proc_dentry)) {
+			dget_locked(proc_dentry);
+			__d_drop(proc_dentry);
+			spin_unlock(&proc_dentry->d_lock);
+		} else {
+			spin_unlock(&proc_dentry->d_lock);
+			proc_dentry = NULL;
+		}
+		spin_unlock(&dcache_lock);
+	}
+	return proc_dentry;
+}
+
+/**
+ * proc_pid_flush - recover memory used by stale /proc/<pid>/x entries
+ * @proc_entry: directoy to prune.
+ *
+ * Shrink the /proc directory that was used by the just killed thread.
+ */
+	
+void proc_pid_flush(struct dentry *proc_dentry)
+{
+	might_sleep();
+	if(proc_dentry != NULL) {
+		shrink_dcache_parent(proc_dentry);
+		dput(proc_dentry);
+	}
+}
+
+/* SMP-safe */
+struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
+{
+	struct task_struct *task;
+	struct inode *inode;
+	struct proc_inode *ei;
+	unsigned tgid;
+	int died;
+
+	if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) {
+		inode = new_inode(dir->i_sb);
+		if (!inode)
+			return ERR_PTR(-ENOMEM);
+		ei = PROC_I(inode);
+		inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+		inode->i_ino = fake_ino(0, PROC_TGID_INO);
+		ei->pde = NULL;
+		inode->i_mode = S_IFLNK|S_IRWXUGO;
+		inode->i_uid = inode->i_gid = 0;
+		inode->i_size = 64;
+		inode->i_op = &proc_self_inode_operations;
+		d_add(dentry, inode);
+		return NULL;
+	}
+	tgid = name_to_int(dentry);
+	if (tgid == ~0U)
+		goto out;
+
+	read_lock(&tasklist_lock);
+	task = find_task_by_pid(tgid);
+	if (task)
+		get_task_struct(task);
+	read_unlock(&tasklist_lock);
+	if (!task)
+		goto out;
+
+	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);
+
+
+	if (!inode) {
+		put_task_struct(task);
+		goto out;
+	}
+	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
+	inode->i_op = &proc_tgid_base_inode_operations;
+	inode->i_fop = &proc_tgid_base_operations;
+	inode->i_nlink = 3;
+	inode->i_flags|=S_IMMUTABLE;
+
+	dentry->d_op = &pid_base_dentry_operations;
+
+	died = 0;
+	d_add(dentry, inode);
+	spin_lock(&task->proc_lock);
+	task->proc_dentry = dentry;
+	if (!pid_alive(task)) {
+		dentry = proc_pid_unhash(task);
+		died = 1;
+	}
+	spin_unlock(&task->proc_lock);
+
+	put_task_struct(task);
+	if (died) {
+		proc_pid_flush(dentry);
+		goto out;
+	}
+	return NULL;
+out:
+	return ERR_PTR(-ENOENT);
+}
+
+/* SMP-safe */
+static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
+{
+	struct task_struct *task;
+	struct task_struct *leader = proc_task(dir);
+	struct inode *inode;
+	unsigned tid;
+
+	tid = name_to_int(dentry);
+	if (tid == ~0U)
+		goto out;
+
+	read_lock(&tasklist_lock);
+	task = find_task_by_pid(tid);
+	if (task)
+		get_task_struct(task);
+	read_unlock(&tasklist_lock);
+	if (!task)
+		goto out;
+	if (leader->tgid != task->tgid)
+		goto out_drop_task;
+
+	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);
+
+
+	if (!inode)
+		goto out_drop_task;
+	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
+	inode->i_op = &proc_tid_base_inode_operations;
+	inode->i_fop = &proc_tid_base_operations;
+	inode->i_nlink = 3;
+	inode->i_flags|=S_IMMUTABLE;
+
+	dentry->d_op = &pid_base_dentry_operations;
+
+	d_add(dentry, inode);
+
+	put_task_struct(task);
+	return NULL;
+out_drop_task:
+	put_task_struct(task);
+out:
+	return ERR_PTR(-ENOENT);
+}
+
+#define PROC_NUMBUF 10
+#define PROC_MAXPIDS 20
+
+/*
+ * Get a few tgid's to return for filldir - we need to hold the
+ * tasklist lock while doing this, and we must release it before
+ * we actually do the filldir itself, so we use a temp buffer..
+ */
+static int get_tgid_list(int index, unsigned long version, unsigned int *tgids)
+{
+	struct task_struct *p;
+	int nr_tgids = 0;
+
+	index--;
+	read_lock(&tasklist_lock);
+	p = NULL;
+	if (version) {
+		p = find_task_by_pid(version);
+		if (p && !thread_group_leader(p))
+			p = NULL;
+	}
+
+	if (p)
+		index = 0;
+	else
+		p = next_task(&init_task);
+
+	for ( ; p != &init_task; p = next_task(p)) {
+		int tgid = p->pid;
+		if (!pid_alive(p))
+			continue;
+		if (--index >= 0)
+			continue;
+		tgids[nr_tgids] = tgid;
+		nr_tgids++;
+		if (nr_tgids >= PROC_MAXPIDS)
+			break;
+	}
+	read_unlock(&tasklist_lock);
+	return nr_tgids;
+}
+
+/*
+ * Get a few tid's to return for filldir - we need to hold the
+ * tasklist lock while doing this, and we must release it before
+ * we actually do the filldir itself, so we use a temp buffer..
+ */
+static int get_tid_list(int index, unsigned int *tids, struct inode *dir)
+{
+	struct task_struct *leader_task = proc_task(dir);
+	struct task_struct *task = leader_task;
+	int nr_tids = 0;
+
+	index -= 2;
+	read_lock(&tasklist_lock);
+	/*
+	 * The starting point task (leader_task) might be an already
+	 * unlinked task, which cannot be used to access the task-list
+	 * via next_thread().
+	 */
+	if (pid_alive(task)) do {
+		int tid = task->pid;
+
+		if (--index >= 0)
+			continue;
+		tids[nr_tids] = tid;
+		nr_tids++;
+		if (nr_tids >= PROC_MAXPIDS)
+			break;
+	} while ((task = next_thread(task)) != leader_task);
+	read_unlock(&tasklist_lock);
+	return nr_tids;
+}
+
+/* for the /proc/ directory itself, after non-process stuff has been done */
+int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
+{
+	unsigned int tgid_array[PROC_MAXPIDS];
+	char buf[PROC_NUMBUF];
+	unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
+	unsigned int nr_tgids, i;
+	int next_tgid;
+
+	if (!nr) {
+		ino_t ino = fake_ino(0,PROC_TGID_INO);
+		if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0)
+			return 0;
+		filp->f_pos++;
+		nr++;
+	}
+
+	/* f_version caches the tgid value that the last readdir call couldn't
+	 * return. lseek aka telldir automagically resets f_version to 0.
+	 */
+	next_tgid = filp->f_version;
+	filp->f_version = 0;
+	for (;;) {
+		nr_tgids = get_tgid_list(nr, next_tgid, tgid_array);
+		if (!nr_tgids) {
+			/* no more entries ! */
+			break;
+		}
+		next_tgid = 0;
+
+		/* do not use the last found pid, reserve it for next_tgid */
+		if (nr_tgids == PROC_MAXPIDS) {
+			nr_tgids--;
+			next_tgid = tgid_array[nr_tgids];
+		}
+
+		for (i=0;i<nr_tgids;i++) {
+			int tgid = tgid_array[i];
+			ino_t ino = fake_ino(tgid,PROC_TGID_INO);
+			unsigned long j = PROC_NUMBUF;
+
+			do
+				buf[--j] = '0' + (tgid % 10);
+			while ((tgid /= 10) != 0);
+
+			if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) {
+				/* returning this tgid failed, save it as the first
+				 * pid for the next readir call */
+				filp->f_version = tgid_array[i];
+				goto out;
+			}
+			filp->f_pos++;
+			nr++;
+		}
+	}
+out:
+	return 0;
+}
+
+/* for the /proc/TGID/task/ directories */
+static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
+{
+	unsigned int tid_array[PROC_MAXPIDS];
+	char buf[PROC_NUMBUF];
+	unsigned int nr_tids, i;
+	struct dentry *dentry = filp->f_dentry;
+	struct inode *inode = dentry->d_inode;
+	int retval = -ENOENT;
+	ino_t ino;
+	unsigned long pos = filp->f_pos;  /* avoiding "long long" filp->f_pos */
+
+	if (!pid_alive(proc_task(inode)))
+		goto out;
+	retval = 0;
+
+	switch (pos) {
+	case 0:
+		ino = inode->i_ino;
+		if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0)
+			goto out;
+		pos++;
+		/* fall through */
+	case 1:
+		ino = parent_ino(dentry);
+		if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0)
+			goto out;
+		pos++;
+		/* fall through */
+	}
+
+	nr_tids = get_tid_list(pos, tid_array, inode);
+
+	for (i = 0; i < nr_tids; i++) {
+		unsigned long j = PROC_NUMBUF;
+		int tid = tid_array[i];
+
+		ino = fake_ino(tid,PROC_TID_INO);
+
+		do
+			buf[--j] = '0' + (tid % 10);
+		while ((tid /= 10) != 0);
+
+		if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0)
+			break;
+		pos++;
+	}
+out:
+	filp->f_pos = pos;
+	return retval;
+}