]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - fs/proc/base.c
d_path: Make proc_get_link() use a struct path argument
[linux-2.6.git] / fs / proc / base.c
index 243a94af0427b2630fb85f489a5419410dac3bfc..47338d92db510d1493389e9534b88f292ad0238a 100644 (file)
 #include <linux/string.h>
 #include <linux/seq_file.h>
 #include <linux/namei.h>
-#include <linux/namespace.h>
+#include <linux/mnt_namespace.h>
 #include <linux/mm.h>
-#include <linux/smp_lock.h>
 #include <linux/rcupdate.h>
 #include <linux/kallsyms.h>
+#include <linux/resource.h>
+#include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/security.h>
 #include <linux/ptrace.h>
-#include <linux/seccomp.h>
+#include <linux/cgroup.h>
 #include <linux/cpuset.h>
 #include <linux/audit.h>
 #include <linux/poll.h>
+#include <linux/nsproxy.h>
+#include <linux/oom.h>
+#include <linux/elf.h>
+#include <linux/pid_namespace.h>
 #include "internal.h"
 
 /* NOTE:
  *     in /proc for a task before it execs a suid executable.
  */
 
-/*
- * 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_NUMA_MAPS,
-       PROC_TGID_MOUNTS,
-       PROC_TGID_MOUNTSTATS,
-       PROC_TGID_WCHAN,
-#ifdef CONFIG_MMU
-       PROC_TGID_SMAPS,
-#endif
-#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,
-       PROC_TGID_ATTR_KEYCREATE,
-       PROC_TGID_ATTR_SOCKCREATE,
-#endif
-#ifdef CONFIG_AUDITSYSCALL
-       PROC_TGID_LOGINUID,
-#endif
-       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_NUMA_MAPS,
-       PROC_TID_MOUNTS,
-       PROC_TID_MOUNTSTATS,
-       PROC_TID_WCHAN,
-#ifdef CONFIG_MMU
-       PROC_TID_SMAPS,
-#endif
-#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,
-       PROC_TID_ATTR_KEYCREATE,
-       PROC_TID_ATTR_SOCKCREATE,
-#endif
-#ifdef CONFIG_AUDITSYSCALL
-       PROC_TID_LOGINUID,
-#endif
-       PROC_TID_OOM_SCORE,
-       PROC_TID_OOM_ADJUST,
-
-       /* Add new entries before this */
-       PROC_TID_FD_DIR = 0x8000,       /* 0x8000-0xffff */
-};
-
-/* Worst case buffer size needed for holding an integer. */
-#define PROC_NUMBUF 10
-
 struct pid_entry {
-       int type;
-       int len;
        char *name;
+       int len;
        mode_t mode;
+       const struct inode_operations *iop;
+       const struct file_operations *fop;
+       union proc_op op;
 };
 
-#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),
-#ifdef CONFIG_NUMA
-       E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
-#endif
-       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),
-       E(PROC_TGID_MOUNTSTATS, "mountstats", S_IFREG|S_IRUSR),
-#ifdef CONFIG_MMU
-       E(PROC_TGID_SMAPS,     "smaps",   S_IFREG|S_IRUGO),
-#endif
-#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),
-#ifdef CONFIG_NUMA
-       E(PROC_TID_NUMA_MAPS,  "numa_maps",    S_IFREG|S_IRUGO),
-#endif
-       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_MMU
-       E(PROC_TID_SMAPS,      "smaps",   S_IFREG|S_IRUGO),
-#endif
-#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),
-       E(PROC_TGID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO),
-       E(PROC_TGID_ATTR_SOCKCREATE, "sockcreate", 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),
-       E(PROC_TID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO),
-       E(PROC_TID_ATTR_SOCKCREATE, "sockcreate", 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 = get_proc_task(inode);
-       struct files_struct *files = NULL;
-       struct file *file;
-       int fd = proc_fd(inode);
-
-       if (task) {
-               files = get_files_struct(task);
-               put_task_struct(task);
-       }
-       if (files) {
-               /*
-                * We are not taking a ref to the file structure, so we must
-                * hold ->file_lock.
-                */
-               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;
+#define NOD(NAME, MODE, IOP, FOP, OP) {                        \
+       .name = (NAME),                                 \
+       .len  = sizeof(NAME) - 1,                       \
+       .mode = MODE,                                   \
+       .iop  = IOP,                                    \
+       .fop  = FOP,                                    \
+       .op   = OP,                                     \
 }
 
+#define DIR(NAME, MODE, OTYPE)                                                 \
+       NOD(NAME, (S_IFDIR|(MODE)),                                             \
+               &proc_##OTYPE##_inode_operations, &proc_##OTYPE##_operations,   \
+               {} )
+#define LNK(NAME, OTYPE)                                       \
+       NOD(NAME, (S_IFLNK|S_IRWXUGO),                          \
+               &proc_pid_link_inode_operations, NULL,          \
+               { .proc_get_link = &proc_##OTYPE##_link } )
+#define REG(NAME, MODE, OTYPE)                         \
+       NOD(NAME, (S_IFREG|(MODE)), NULL,               \
+               &proc_##OTYPE##_operations, {})
+#define INF(NAME, MODE, OTYPE)                         \
+       NOD(NAME, (S_IFREG|(MODE)),                     \
+               NULL, &proc_info_file_operations,       \
+               { .proc_read = &proc_##OTYPE } )
+#define ONE(NAME, MODE, OTYPE)                         \
+       NOD(NAME, (S_IFREG|(MODE)),                     \
+               NULL, &proc_single_file_operations,     \
+               { .proc_show = &proc_##OTYPE } )
+
+int maps_protect;
+EXPORT_SYMBOL(maps_protect);
+
 static struct fs_struct *get_fs_struct(struct task_struct *task)
 {
        struct fs_struct *fs;
@@ -363,7 +153,7 @@ static int get_nr_threads(struct task_struct *tsk)
        return count;
 }
 
-static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
+static int proc_cwd_link(struct inode *inode, struct path *path)
 {
        struct task_struct *task = get_proc_task(inode);
        struct fs_struct *fs = NULL;
@@ -375,8 +165,8 @@ static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfs
        }
        if (fs) {
                read_lock(&fs->lock);
-               *mnt = mntget(fs->pwdmnt);
-               *dentry = dget(fs->pwd);
+               *path = fs->pwd;
+               path_get(&fs->pwd);
                read_unlock(&fs->lock);
                result = 0;
                put_fs_struct(fs);
@@ -384,7 +174,7 @@ static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfs
        return result;
 }
 
-static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
+static int proc_root_link(struct inode *inode, struct path *path)
 {
        struct task_struct *task = get_proc_task(inode);
        struct fs_struct *fs = NULL;
@@ -396,8 +186,8 @@ static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vf
        }
        if (fs) {
                read_lock(&fs->lock);
-               *mnt = mntget(fs->rootmnt);
-               *dentry = dget(fs->root);
+               *path = fs->root;
+               path_get(&fs->root);
                read_unlock(&fs->lock);
                result = 0;
                put_fs_struct(fs);
@@ -409,23 +199,27 @@ static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vf
        (task == current || \
        (task->parent == current && \
        (task->ptrace & PT_PTRACED) && \
-        (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
+        (task_is_stopped_or_traced(task)) && \
         security_ptrace(current,task) == 0))
 
-static int proc_pid_environ(struct task_struct *task, char * buffer)
+struct mm_struct *mm_for_maps(struct task_struct *task)
 {
-       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 (!ptrace_may_attach(task))
-                       res = -ESRCH;
-               mmput(mm);
-       }
-       return res;
+       if (!mm)
+               return NULL;
+       down_read(&mm->mmap_sem);
+       task_lock(task);
+       if (task->mm != mm)
+               goto out;
+       if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
+               goto out;
+       task_unlock(task);
+       return mm;
+out:
+       task_unlock(task);
+       up_read(&mm->mmap_sem);
+       mmput(mm);
+       return NULL;
 }
 
 static int proc_pid_cmdline(struct task_struct *task, char * buffer)
@@ -491,17 +285,15 @@ static int proc_pid_auxv(struct task_struct *task, char *buffer)
  */
 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];
+       unsigned long wchan;
+       char symname[KSYM_NAME_LEN];
 
        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);
+       if (lookup_symbol_name(wchan, symname) < 0)
+               return sprintf(buffer, "%lu", wchan);
+       else
+               return sprintf(buffer, "%s", symname);
 }
 #endif /* CONFIG_KALLSYMS */
 
@@ -511,11 +303,82 @@ static int proc_pid_wchan(struct task_struct *task, char *buffer)
  */
 static int proc_pid_schedstat(struct task_struct *task, char *buffer)
 {
-       return sprintf(buffer, "%lu %lu %lu\n",
+       return sprintf(buffer, "%llu %llu %lu\n",
                        task->sched_info.cpu_time,
                        task->sched_info.run_delay,
-                       task->sched_info.pcnt);
+                       task->sched_info.pcount);
+}
+#endif
+
+#ifdef CONFIG_LATENCYTOP
+static int lstats_show_proc(struct seq_file *m, void *v)
+{
+       int i;
+       struct task_struct *task = m->private;
+       seq_puts(m, "Latency Top version : v0.1\n");
+
+       for (i = 0; i < 32; i++) {
+               if (task->latency_record[i].backtrace[0]) {
+                       int q;
+                       seq_printf(m, "%i %li %li ",
+                               task->latency_record[i].count,
+                               task->latency_record[i].time,
+                               task->latency_record[i].max);
+                       for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
+                               char sym[KSYM_NAME_LEN];
+                               char *c;
+                               if (!task->latency_record[i].backtrace[q])
+                                       break;
+                               if (task->latency_record[i].backtrace[q] == ULONG_MAX)
+                                       break;
+                               sprint_symbol(sym, task->latency_record[i].backtrace[q]);
+                               c = strchr(sym, '+');
+                               if (c)
+                                       *c = 0;
+                               seq_printf(m, "%s ", sym);
+                       }
+                       seq_printf(m, "\n");
+               }
+
+       }
+       return 0;
+}
+
+static int lstats_open(struct inode *inode, struct file *file)
+{
+       int ret;
+       struct seq_file *m;
+       struct task_struct *task = get_proc_task(inode);
+
+       ret = single_open(file, lstats_show_proc, NULL);
+       if (!ret) {
+               m = file->private_data;
+               m->private = task;
+       }
+       return ret;
+}
+
+static ssize_t lstats_write(struct file *file, const char __user *buf,
+                           size_t count, loff_t *offs)
+{
+       struct seq_file *m;
+       struct task_struct *task;
+
+       m = file->private_data;
+       task = m->private;
+       clear_all_latency_tracing(task);
+
+       return count;
 }
+
+static const struct file_operations proc_lstats_operations = {
+       .open           = lstats_open,
+       .read           = seq_read,
+       .write          = lstats_write,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
 #endif
 
 /* The badness from the OOM killer */
@@ -526,10 +389,84 @@ static int proc_oom_score(struct task_struct *task, char *buffer)
        struct timespec uptime;
 
        do_posix_clock_monotonic_gettime(&uptime);
+       read_lock(&tasklist_lock);
        points = badness(task, uptime.tv_sec);
+       read_unlock(&tasklist_lock);
        return sprintf(buffer, "%lu\n", points);
 }
 
+struct limit_names {
+       char *name;
+       char *unit;
+};
+
+static const struct limit_names lnames[RLIM_NLIMITS] = {
+       [RLIMIT_CPU] = {"Max cpu time", "ms"},
+       [RLIMIT_FSIZE] = {"Max file size", "bytes"},
+       [RLIMIT_DATA] = {"Max data size", "bytes"},
+       [RLIMIT_STACK] = {"Max stack size", "bytes"},
+       [RLIMIT_CORE] = {"Max core file size", "bytes"},
+       [RLIMIT_RSS] = {"Max resident set", "bytes"},
+       [RLIMIT_NPROC] = {"Max processes", "processes"},
+       [RLIMIT_NOFILE] = {"Max open files", "files"},
+       [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
+       [RLIMIT_AS] = {"Max address space", "bytes"},
+       [RLIMIT_LOCKS] = {"Max file locks", "locks"},
+       [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
+       [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
+       [RLIMIT_NICE] = {"Max nice priority", NULL},
+       [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
+};
+
+/* Display limits for a process */
+static int proc_pid_limits(struct task_struct *task, char *buffer)
+{
+       unsigned int i;
+       int count = 0;
+       unsigned long flags;
+       char *bufptr = buffer;
+
+       struct rlimit rlim[RLIM_NLIMITS];
+
+       rcu_read_lock();
+       if (!lock_task_sighand(task,&flags)) {
+               rcu_read_unlock();
+               return 0;
+       }
+       memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
+       unlock_task_sighand(task, &flags);
+       rcu_read_unlock();
+
+       /*
+        * print the file header
+        */
+       count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
+                       "Limit", "Soft Limit", "Hard Limit", "Units");
+
+       for (i = 0; i < RLIM_NLIMITS; i++) {
+               if (rlim[i].rlim_cur == RLIM_INFINITY)
+                       count += sprintf(&bufptr[count], "%-25s %-20s ",
+                                        lnames[i].name, "unlimited");
+               else
+                       count += sprintf(&bufptr[count], "%-25s %-20lu ",
+                                        lnames[i].name, rlim[i].rlim_cur);
+
+               if (rlim[i].rlim_max == RLIM_INFINITY)
+                       count += sprintf(&bufptr[count], "%-20s ", "unlimited");
+               else
+                       count += sprintf(&bufptr[count], "%-20lu ",
+                                        rlim[i].rlim_max);
+
+               if (lnames[i].unit)
+                       count += sprintf(&bufptr[count], "%-10s\n",
+                                        lnames[i].unit);
+               else
+                       count += sprintf(&bufptr[count], "\n");
+       }
+
+       return count;
+}
+
 /************************************************************************/
 /*                       Here the fs part begins                        */
 /************************************************************************/
@@ -551,7 +488,25 @@ static int proc_fd_access_allowed(struct inode *inode)
        return allowed;
 }
 
-extern struct seq_operations mounts_op;
+static int proc_setattr(struct dentry *dentry, struct iattr *attr)
+{
+       int error;
+       struct inode *inode = dentry->d_inode;
+
+       if (attr->ia_valid & ATTR_MODE)
+               return -EPERM;
+
+       error = inode_change_ok(inode, attr);
+       if (!error)
+               error = inode_setattr(inode, attr);
+       return error;
+}
+
+static const struct inode_operations proc_def_inode_operations = {
+       .setattr        = proc_setattr,
+};
+
+extern const struct seq_operations mounts_op;
 struct proc_mounts {
        struct seq_file m;
        int event;
@@ -560,33 +515,38 @@ struct proc_mounts {
 static int mounts_open(struct inode *inode, struct file *file)
 {
        struct task_struct *task = get_proc_task(inode);
-       struct namespace *namespace = NULL;
+       struct nsproxy *nsp;
+       struct mnt_namespace *ns = NULL;
        struct proc_mounts *p;
        int ret = -EINVAL;
 
        if (task) {
-               task_lock(task);
-               namespace = task->namespace;
-               if (namespace)
-                       get_namespace(namespace);
-               task_unlock(task);
+               rcu_read_lock();
+               nsp = task_nsproxy(task);
+               if (nsp) {
+                       ns = nsp->mnt_ns;
+                       if (ns)
+                               get_mnt_ns(ns);
+               }
+               rcu_read_unlock();
+
                put_task_struct(task);
        }
 
-       if (namespace) {
+       if (ns) {
                ret = -ENOMEM;
                p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
                if (p) {
                        file->private_data = &p->m;
                        ret = seq_open(file, &mounts_op);
                        if (!ret) {
-                               p->m.private = namespace;
-                               p->event = namespace->event;
+                               p->m.private = ns;
+                               p->event = ns->event;
                                return 0;
                        }
                        kfree(p);
                }
-               put_namespace(namespace);
+               put_mnt_ns(ns);
        }
        return ret;
 }
@@ -594,15 +554,15 @@ static int mounts_open(struct inode *inode, struct file *file)
 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);
+       struct mnt_namespace *ns = m->private;
+       put_mnt_ns(ns);
        return seq_release(inode, file);
 }
 
 static unsigned mounts_poll(struct file *file, poll_table *wait)
 {
        struct proc_mounts *p = file->private_data;
-       struct namespace *ns = p->m.private;
+       struct mnt_namespace *ns = p->m.private;
        unsigned res = 0;
 
        poll_wait(file, &ns->poll, wait);
@@ -617,7 +577,7 @@ static unsigned mounts_poll(struct file *file, poll_table *wait)
        return res;
 }
 
-static struct file_operations proc_mounts_operations = {
+static const struct file_operations proc_mounts_operations = {
        .open           = mounts_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
@@ -625,27 +585,32 @@ static struct file_operations proc_mounts_operations = {
        .poll           = mounts_poll,
 };
 
-extern struct seq_operations mountstats_op;
+extern const struct seq_operations mountstats_op;
 static int mountstats_open(struct inode *inode, struct file *file)
 {
        int ret = seq_open(file, &mountstats_op);
 
        if (!ret) {
                struct seq_file *m = file->private_data;
-               struct namespace *namespace = NULL;
+               struct nsproxy *nsp;
+               struct mnt_namespace *mnt_ns = NULL;
                struct task_struct *task = get_proc_task(inode);
 
                if (task) {
-                       task_lock(task);
-                       namespace = task->namespace;
-                       if (namespace)
-                               get_namespace(namespace);
-                       task_unlock(task);
+                       rcu_read_lock();
+                       nsp = task_nsproxy(task);
+                       if (nsp) {
+                               mnt_ns = nsp->mnt_ns;
+                               if (mnt_ns)
+                                       get_mnt_ns(mnt_ns);
+                       }
+                       rcu_read_unlock();
+
                        put_task_struct(task);
                }
 
-               if (namespace)
-                       m->private = namespace;
+               if (mnt_ns)
+                       m->private = mnt_ns;
                else {
                        seq_release(inode, file);
                        ret = -EINVAL;
@@ -654,7 +619,7 @@ static int mountstats_open(struct inode *inode, struct file *file)
        return ret;
 }
 
-static struct file_operations proc_mountstats_operations = {
+static const struct file_operations proc_mountstats_operations = {
        .open           = mountstats_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
@@ -666,7 +631,7 @@ static struct file_operations proc_mountstats_operations = {
 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;
+       struct inode * inode = file->f_path.dentry->d_inode;
        unsigned long page;
        ssize_t length;
        struct task_struct *task = get_proc_task(inode);
@@ -679,7 +644,7 @@ static ssize_t proc_info_read(struct file * file, char __user * buf,
                count = PROC_BLOCK_SIZE;
 
        length = -ENOMEM;
-       if (!(page = __get_free_page(GFP_KERNEL)))
+       if (!(page = __get_free_page(GFP_TEMPORARY)))
                goto out;
 
        length = PROC_I(inode)->op.proc_read(task, (char*)page);
@@ -693,10 +658,49 @@ out_no_task:
        return length;
 }
 
-static struct file_operations proc_info_file_operations = {
+static const struct file_operations proc_info_file_operations = {
        .read           = proc_info_read,
 };
 
+static int proc_single_show(struct seq_file *m, void *v)
+{
+       struct inode *inode = m->private;
+       struct pid_namespace *ns;
+       struct pid *pid;
+       struct task_struct *task;
+       int ret;
+
+       ns = inode->i_sb->s_fs_info;
+       pid = proc_pid(inode);
+       task = get_pid_task(pid, PIDTYPE_PID);
+       if (!task)
+               return -ESRCH;
+
+       ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
+
+       put_task_struct(task);
+       return ret;
+}
+
+static int proc_single_open(struct inode *inode, struct file *filp)
+{
+       int ret;
+       ret = single_open(filp, proc_single_show, NULL);
+       if (!ret) {
+               struct seq_file *m = filp->private_data;
+
+               m->private = inode;
+       }
+       return ret;
+}
+
+static const struct file_operations proc_single_file_operations = {
+       .open           = proc_single_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
 static int mem_open(struct inode* inode, struct file* file)
 {
        file->private_data = (void*)((long)current->self_exec_id);
@@ -706,7 +710,7 @@ static int mem_open(struct inode* inode, struct file* file)
 static ssize_t mem_read(struct file * file, char __user * buf,
                        size_t count, loff_t *ppos)
 {
-       struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+       struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
        char *page;
        unsigned long src = *ppos;
        int ret = -ESRCH;
@@ -719,7 +723,7 @@ static ssize_t mem_read(struct file * file, char __user * buf,
                goto out;
 
        ret = -ENOMEM;
-       page = (char *)__get_free_page(GFP_USER);
+       page = (char *)__get_free_page(GFP_TEMPORARY);
        if (!page)
                goto out;
 
@@ -773,12 +777,12 @@ out_no_task:
 
 #ifndef mem_write
 /* This is a security hazard */
-static ssize_t mem_write(struct file * file, const char buf,
+static ssize_t mem_write(struct file * file, const char __user *buf,
                         size_t count, loff_t *ppos)
 {
-       int copied = 0;
+       int copied;
        char *page;
-       struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+       struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
        unsigned long dst = *ppos;
 
        copied = -ESRCH;
@@ -789,10 +793,11 @@ static ssize_t mem_write(struct file * file, const char * buf,
                goto out;
 
        copied = -ENOMEM;
-       page = (char *)__get_free_page(GFP_USER);
+       page = (char *)__get_free_page(GFP_TEMPORARY);
        if (!page)
                goto out;
 
+       copied = 0;
        while (count > 0) {
                int this_len, retval;
 
@@ -821,7 +826,7 @@ out_no_task:
 }
 #endif
 
-static loff_t mem_lseek(struct file * file, loff_t offset, int orig)
+loff_t mem_lseek(struct file *file, loff_t offset, int orig)
 {
        switch (orig) {
        case 0:
@@ -837,68 +842,134 @@ static loff_t mem_lseek(struct file * file, loff_t offset, int orig)
        return file->f_pos;
 }
 
-static struct file_operations proc_mem_operations = {
+static const 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)
+static ssize_t environ_read(struct file *file, char __user *buf,
+                       size_t count, loff_t *ppos)
 {
        struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
-       char buffer[PROC_NUMBUF];
-       size_t len;
-       int oom_adjust;
-       loff_t __ppos = *ppos;
+       char *page;
+       unsigned long src = *ppos;
+       int ret = -ESRCH;
+       struct mm_struct *mm;
 
        if (!task)
-               return -ESRCH;
-       oom_adjust = task->oomkilladj;
-       put_task_struct(task);
+               goto out_no_task;
 
-       len = snprintf(buffer, sizeof(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;
-}
+       if (!ptrace_may_attach(task))
+               goto out;
 
-static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
-                               size_t count, loff_t *ppos)
-{
-       struct task_struct *task;
-       char buffer[PROC_NUMBUF], *end;
-       int oom_adjust;
+       ret = -ENOMEM;
+       page = (char *)__get_free_page(GFP_TEMPORARY);
+       if (!page)
+               goto out;
 
-       if (!capable(CAP_SYS_RESOURCE))
-               return -EPERM;
-       memset(buffer, 0, sizeof(buffer));
-       if (count > sizeof(buffer) - 1)
-               count = sizeof(buffer) - 1;
-       if (copy_from_user(buffer, buf, count))
-               return -EFAULT;
-       oom_adjust = simple_strtol(buffer, &end, 0);
-       if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE)
-               return -EINVAL;
-       if (*end == '\n')
-               end++;
-       task = get_proc_task(file->f_dentry->d_inode);
-       if (!task)
-               return -ESRCH;
-       task->oomkilladj = oom_adjust;
-       put_task_struct(task);
+       ret = 0;
+
+       mm = get_task_mm(task);
+       if (!mm)
+               goto out_free;
+
+       while (count > 0) {
+               int this_len, retval, max_len;
+
+               this_len = mm->env_end - (mm->env_start + src);
+
+               if (this_len <= 0)
+                       break;
+
+               max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
+               this_len = (this_len > max_len) ? max_len : this_len;
+
+               retval = access_process_vm(task, (mm->env_start + src),
+                       page, this_len, 0);
+
+               if (retval <= 0) {
+                       ret = retval;
+                       break;
+               }
+
+               if (copy_to_user(buf, page, retval)) {
+                       ret = -EFAULT;
+                       break;
+               }
+
+               ret += retval;
+               src += retval;
+               buf += retval;
+               count -= retval;
+       }
+       *ppos = src;
+
+       mmput(mm);
+out_free:
+       free_page((unsigned long) page);
+out:
+       put_task_struct(task);
+out_no_task:
+       return ret;
+}
+
+static const struct file_operations proc_environ_operations = {
+       .read           = environ_read,
+};
+
+static ssize_t oom_adjust_read(struct file *file, char __user *buf,
+                               size_t count, loff_t *ppos)
+{
+       struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
+       char buffer[PROC_NUMBUF];
+       size_t len;
+       int oom_adjust;
+
+       if (!task)
+               return -ESRCH;
+       oom_adjust = task->oomkilladj;
+       put_task_struct(task);
+
+       len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
+
+       return simple_read_from_buffer(buf, count, ppos, buffer, len);
+}
+
+static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
+                               size_t count, loff_t *ppos)
+{
+       struct task_struct *task;
+       char buffer[PROC_NUMBUF], *end;
+       int oom_adjust;
+
+       memset(buffer, 0, sizeof(buffer));
+       if (count > sizeof(buffer) - 1)
+               count = sizeof(buffer) - 1;
+       if (copy_from_user(buffer, buf, count))
+               return -EFAULT;
+       oom_adjust = simple_strtol(buffer, &end, 0);
+       if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
+            oom_adjust != OOM_DISABLE)
+               return -EINVAL;
+       if (*end == '\n')
+               end++;
+       task = get_proc_task(file->f_path.dentry->d_inode);
+       if (!task)
+               return -ESRCH;
+       if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) {
+               put_task_struct(task);
+               return -EACCES;
+       }
+       task->oomkilladj = oom_adjust;
+       put_task_struct(task);
        if (end - buffer == 0)
                return -EIO;
        return end - buffer;
 }
 
-static struct file_operations proc_oom_adjust_operations = {
+static const struct file_operations proc_oom_adjust_operations = {
        .read           = oom_adjust_read,
        .write          = oom_adjust_write,
 };
@@ -908,7 +979,7 @@ static struct file_operations proc_oom_adjust_operations = {
 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 inode * inode = file->f_path.dentry->d_inode;
        struct task_struct *task = get_proc_task(inode);
        ssize_t length;
        char tmpbuf[TMPBUFLEN];
@@ -916,7 +987,7 @@ static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
        if (!task)
                return -ESRCH;
        length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
-                               audit_get_loginuid(task->audit_context));
+                               audit_get_loginuid(task));
        put_task_struct(task);
        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 }
@@ -924,7 +995,7 @@ static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
 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;
+       struct inode * inode = file->f_path.dentry->d_inode;
        char *page, *tmp;
        ssize_t length;
        uid_t loginuid;
@@ -942,7 +1013,7 @@ static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
                /* No partial writes. */
                return -EINVAL;
        }
-       page = (char*)__get_free_page(GFP_USER);
+       page = (char*)__get_free_page(GFP_TEMPORARY);
        if (!page)
                return -ENOMEM;
        length = -EFAULT;
@@ -965,83 +1036,127 @@ out_free_page:
        return length;
 }
 
-static struct file_operations proc_loginuid_operations = {
+static const 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)
+#ifdef CONFIG_FAULT_INJECTION
+static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
+                                     size_t count, loff_t *ppos)
 {
-       struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode);
-       char __buf[20];
-       loff_t __ppos = *ppos;
+       struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+       char buffer[PROC_NUMBUF];
        size_t len;
+       int make_it_fail;
 
-       if (!tsk)
+       if (!task)
                return -ESRCH;
-       /* no need to print the trailing zero, so use only len */
-       len = sprintf(__buf, "%u\n", tsk->seccomp.mode);
-       put_task_struct(tsk);
-       if (__ppos >= len)
-               return 0;
-       if (count > len - __ppos)
-               count = len - __ppos;
-       if (copy_to_user(buf, __buf + __ppos, count))
+       make_it_fail = task->make_it_fail;
+       put_task_struct(task);
+
+       len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
+
+       return simple_read_from_buffer(buf, count, ppos, buffer, len);
+}
+
+static ssize_t proc_fault_inject_write(struct file * file,
+                       const char __user * buf, size_t count, loff_t *ppos)
+{
+       struct task_struct *task;
+       char buffer[PROC_NUMBUF], *end;
+       int make_it_fail;
+
+       if (!capable(CAP_SYS_RESOURCE))
+               return -EPERM;
+       memset(buffer, 0, sizeof(buffer));
+       if (count > sizeof(buffer) - 1)
+               count = sizeof(buffer) - 1;
+       if (copy_from_user(buffer, buf, count))
                return -EFAULT;
-       *ppos = __ppos + count;
-       return count;
+       make_it_fail = simple_strtol(buffer, &end, 0);
+       if (*end == '\n')
+               end++;
+       task = get_proc_task(file->f_dentry->d_inode);
+       if (!task)
+               return -ESRCH;
+       task->make_it_fail = make_it_fail;
+       put_task_struct(task);
+       if (end - buffer == 0)
+               return -EIO;
+       return end - buffer;
 }
 
-static ssize_t seccomp_write(struct file *file, const char __user *buf,
-                            size_t count, loff_t *ppos)
+static const struct file_operations proc_fault_inject_operations = {
+       .read           = proc_fault_inject_read,
+       .write          = proc_fault_inject_write,
+};
+#endif
+
+
+#ifdef CONFIG_SCHED_DEBUG
+/*
+ * Print out various scheduling related per-task fields:
+ */
+static int sched_show(struct seq_file *m, void *v)
 {
-       struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode);
-       char __buf[20], *end;
-       unsigned int seccomp_mode;
-       ssize_t result;
+       struct inode *inode = m->private;
+       struct task_struct *p;
 
-       result = -ESRCH;
-       if (!tsk)
-               goto out_no_task;
+       WARN_ON(!inode);
 
-       /* can set it only once to be even more secure */
-       result = -EPERM;
-       if (unlikely(tsk->seccomp.mode))
-               goto out;
+       p = get_proc_task(inode);
+       if (!p)
+               return -ESRCH;
+       proc_sched_show_task(p, m);
 
-       result = -EFAULT;
-       memset(__buf, 0, sizeof(__buf));
-       count = min(count, sizeof(__buf) - 1);
-       if (copy_from_user(__buf, buf, count))
-               goto out;
+       put_task_struct(p);
 
-       seccomp_mode = simple_strtoul(__buf, &end, 0);
-       if (*end == '\n')
-               end++;
-       result = -EINVAL;
-       if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) {
-               tsk->seccomp.mode = seccomp_mode;
-               set_tsk_thread_flag(tsk, TIF_SECCOMP);
-       } else
-               goto out;
-       result = -EIO;
-       if (unlikely(!(end - __buf)))
-               goto out;
-       result = end - __buf;
-out:
-       put_task_struct(tsk);
-out_no_task:
-       return result;
+       return 0;
+}
+
+static ssize_t
+sched_write(struct file *file, const char __user *buf,
+           size_t count, loff_t *offset)
+{
+       struct inode *inode = file->f_path.dentry->d_inode;
+       struct task_struct *p;
+
+       WARN_ON(!inode);
+
+       p = get_proc_task(inode);
+       if (!p)
+               return -ESRCH;
+       proc_sched_set_task(p);
+
+       put_task_struct(p);
+
+       return count;
+}
+
+static int sched_open(struct inode *inode, struct file *filp)
+{
+       int ret;
+
+       ret = single_open(filp, sched_show, NULL);
+       if (!ret) {
+               struct seq_file *m = filp->private_data;
+
+               m->private = inode;
+       }
+       return ret;
 }
 
-static struct file_operations proc_seccomp_operations = {
-       .read           = seccomp_read,
-       .write          = seccomp_write,
+static const struct file_operations proc_pid_sched_operations = {
+       .open           = sched_open,
+       .read           = seq_read,
+       .write          = sched_write,
+       .llseek         = seq_lseek,
+       .release        = single_release,
 };
-#endif /* CONFIG_SECCOMP */
+
+#endif
 
 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
@@ -1049,38 +1164,36 @@ static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
        int error = -EACCES;
 
        /* We don't need a base pointer in the /proc filesystem */
-       path_release(nd);
+       path_put(&nd->path);
 
        /* Are we allowed to snoop on the tasks file descriptors? */
        if (!proc_fd_access_allowed(inode))
                goto out;
 
-       error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
+       error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
        nd->last_type = LAST_BIND;
 out:
        return ERR_PTR(error);
 }
 
-static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
-                           char __user *buffer, int buflen)
+static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
 {
-       struct inode * inode;
-       char *tmp = (char*)__get_free_page(GFP_KERNEL), *path;
+       char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
+       char *pathname;
        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))
+
+       pathname = d_path(path->dentry, path->mnt, tmp, PAGE_SIZE);
+       len = PTR_ERR(pathname);
+       if (IS_ERR(pathname))
                goto out;
-       len = tmp + PAGE_SIZE - 1 - path;
+       len = tmp + PAGE_SIZE - 1 - pathname;
 
        if (len > buflen)
                len = buflen;
-       if (copy_to_user(buffer, path, len))
+       if (copy_to_user(buffer, pathname, len))
                len = -EFAULT;
  out:
        free_page((unsigned long)tmp);
@@ -1091,224 +1204,107 @@ static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int b
 {
        int error = -EACCES;
        struct inode *inode = dentry->d_inode;
-       struct dentry *de;
-       struct vfsmount *mnt = NULL;
+       struct path path;
 
        /* Are we allowed to snoop on the tasks file descriptors? */
        if (!proc_fd_access_allowed(inode))
                goto out;
 
-       error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
+       error = PROC_I(inode)->op.proc_get_link(inode, &path);
        if (error)
                goto out;
 
-       error = do_proc_readlink(de, mnt, buffer, buflen);
-       dput(de);
-       mntput(mnt);
+       error = do_proc_readlink(&path, buffer, buflen);
+       path_put(&path);
 out:
        return error;
 }
 
-static struct inode_operations proc_pid_link_inode_operations = {
+static const struct inode_operations proc_pid_link_inode_operations = {
        .readlink       = proc_pid_readlink,
-       .follow_link    = proc_pid_follow_link
+       .follow_link    = proc_pid_follow_link,
+       .setattr        = proc_setattr,
 };
 
-static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
+
+/* building an inode */
+
+static int task_dumpable(struct task_struct *task)
 {
-       struct dentry *dentry = filp->f_dentry;
-       struct inode *inode = dentry->d_inode;
-       struct task_struct *p = get_proc_task(inode);
-       unsigned int fd, tid, ino;
-       int retval;
-       char buf[PROC_NUMBUF];
-       struct files_struct * files;
-       struct fdtable *fdt;
+       int dumpable = 0;
+       struct mm_struct *mm;
 
-       retval = -ENOENT;
-       if (!p)
-               goto out_no_task;
-       retval = 0;
-       tid = p->pid;
+       task_lock(task);
+       mm = task->mm;
+       if (mm)
+               dumpable = get_dumpable(mm);
+       task_unlock(task);
+       if(dumpable == 1)
+               return 1;
+       return 0;
+}
 
-       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 = parent_ino(dentry);
-                       if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
-                               goto out;
-                       filp->f_pos++;
-               default:
-                       files = get_files_struct(p);
-                       if (!files)
-                               goto out;
-                       rcu_read_lock();
-                       fdt = files_fdtable(files);
-                       for (fd = filp->f_pos-2;
-                            fd < fdt->max_fds;
-                            fd++, filp->f_pos++) {
-                               unsigned int i,j;
 
-                               if (!fcheck_files(files, fd))
-                                       continue;
-                               rcu_read_unlock();
+static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
+{
+       struct inode * inode;
+       struct proc_inode *ei;
 
-                               j = PROC_NUMBUF;
-                               i = fd;
-                               do {
-                                       j--;
-                                       buf[j] = '0' + (i % 10);
-                                       i /= 10;
-                               } while (i);
+       /* We need a new inode */
 
-                               ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
-                               if (filldir(dirent, buf+j, PROC_NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
-                                       rcu_read_lock();
-                                       break;
-                               }
-                               rcu_read_lock();
-                       }
-                       rcu_read_unlock();
-                       put_files_struct(files);
+       inode = new_inode(sb);
+       if (!inode)
+               goto out;
+
+       /* Common stuff */
+       ei = PROC_I(inode);
+       inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+       inode->i_op = &proc_def_inode_operations;
+
+       /*
+        * grab the reference to task.
+        */
+       ei->pid = get_task_pid(task, PIDTYPE_PID);
+       if (!ei->pid)
+               goto out_unlock;
+
+       inode->i_uid = 0;
+       inode->i_gid = 0;
+       if (task_dumpable(task)) {
+               inode->i_uid = task->euid;
+               inode->i_gid = task->egid;
        }
+       security_task_to_inode(task, inode);
+
 out:
-       put_task_struct(p);
-out_no_task:
-       return retval;
+       return inode;
+
+out_unlock:
+       iput(inode);
+       return NULL;
 }
 
-static int proc_pident_readdir(struct file *filp,
-               void *dirent, filldir_t filldir,
-               struct pid_entry *ents, unsigned int nents)
+static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 {
-       int i;
-       int pid;
-       struct dentry *dentry = filp->f_dentry;
        struct inode *inode = dentry->d_inode;
-       struct task_struct *task = get_proc_task(inode);
-       struct pid_entry *p;
-       ino_t ino;
-       int ret;
-
-       ret = -ENOENT;
-       if (!task)
-               goto out;
+       struct task_struct *task;
+       generic_fillattr(inode, stat);
 
-       ret = 0;
-       pid = task->pid;
-       put_task_struct(task);
-       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++;
+       rcu_read_lock();
+       stat->uid = 0;
+       stat->gid = 0;
+       task = pid_task(proc_pid(inode), PIDTYPE_PID);
+       if (task) {
+               if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
+                   task_dumpable(task)) {
+                       stat->uid = task->euid;
+                       stat->gid = task->egid;
                }
        }
-
-       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);
-       if(dumpable == 1)
-               return 1;
+       rcu_read_unlock();
        return 0;
 }
 
-
-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);
-       inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
-       inode->i_ino = fake_ino(task->pid, ino);
-
-       /*
-        * grab the reference to task.
-        */
-       ei->pid = get_pid(task->pids[PIDTYPE_PID].pid);
-       if (!ei->pid)
-               goto out_unlock;
-
-       inode->i_uid = 0;
-       inode->i_gid = 0;
-       if (task_dumpable(task)) {
-               inode->i_uid = task->euid;
-               inode->i_gid = task->egid;
-       }
-       security_task_to_inode(task, inode);
-
-out:
-       return inode;
-
-out_unlock:
-       iput(inode);
-       return NULL;
-}
-
 /* dentry stuff */
 
 /*
@@ -1339,6 +1335,7 @@ static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
                        inode->i_uid = 0;
                        inode->i_gid = 0;
                }
+               inode->i_mode &= ~(S_ISUID | S_ISGID);
                security_task_to_inode(task, inode);
                put_task_struct(task);
                return 1;
@@ -1347,25 +1344,146 @@ static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
        return 0;
 }
 
-static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+static int pid_delete_dentry(struct dentry * dentry)
 {
-       struct inode *inode = dentry->d_inode;
-       struct task_struct *task;
-       generic_fillattr(inode, stat);
+       /* Is the task we represent dead?
+        * If so, then don't put the dentry on the lru list,
+        * kill it immediately.
+        */
+       return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
+}
+
+static struct dentry_operations pid_dentry_operations =
+{
+       .d_revalidate   = pid_revalidate,
+       .d_delete       = pid_delete_dentry,
+};
+
+/* Lookups */
+
+typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
+                               struct task_struct *, const void *);
+
+/*
+ * Fill a directory entry.
+ *
+ * If possible create the dcache entry and derive our inode number and
+ * file type from dcache entry.
+ *
+ * Since all of the proc inode numbers are dynamically generated, the inode
+ * numbers do not exist until the inode is cache.  This means creating the
+ * the dcache entry in readdir is necessary to keep the inode numbers
+ * reported by readdir in sync with the inode numbers reported
+ * by stat.
+ */
+static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
+       char *name, int len,
+       instantiate_t instantiate, struct task_struct *task, const void *ptr)
+{
+       struct dentry *child, *dir = filp->f_path.dentry;
+       struct inode *inode;
+       struct qstr qname;
+       ino_t ino = 0;
+       unsigned type = DT_UNKNOWN;
+
+       qname.name = name;
+       qname.len  = len;
+       qname.hash = full_name_hash(name, len);
+
+       child = d_lookup(dir, &qname);
+       if (!child) {
+               struct dentry *new;
+               new = d_alloc(dir, &qname);
+               if (new) {
+                       child = instantiate(dir->d_inode, new, task, ptr);
+                       if (child)
+                               dput(new);
+                       else
+                               child = new;
+               }
+       }
+       if (!child || IS_ERR(child) || !child->d_inode)
+               goto end_instantiate;
+       inode = child->d_inode;
+       if (inode) {
+               ino = inode->i_ino;
+               type = inode->i_mode >> 12;
+       }
+       dput(child);
+end_instantiate:
+       if (!ino)
+               ino = find_inode_number(dir, &qname);
+       if (!ino)
+               ino = 1;
+       return filldir(dirent, name, len, filp->f_pos, ino, type);
+}
+
+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;
+}
+
+#define PROC_FDINFO_MAX 64
+
+static int proc_fd_info(struct inode *inode, struct path *path, char *info)
+{
+       struct task_struct *task = get_proc_task(inode);
+       struct files_struct *files = NULL;
+       struct file *file;
+       int fd = proc_fd(inode);
 
-       rcu_read_lock();
-       stat->uid = 0;
-       stat->gid = 0;
-       task = pid_task(proc_pid(inode), PIDTYPE_PID);
        if (task) {
-               if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
-                   task_dumpable(task)) {
-                       stat->uid = task->euid;
-                       stat->gid = task->egid;
+               files = get_files_struct(task);
+               put_task_struct(task);
+       }
+       if (files) {
+               /*
+                * We are not taking a ref to the file structure, so we must
+                * hold ->file_lock.
+                */
+               spin_lock(&files->file_lock);
+               file = fcheck_files(files, fd);
+               if (file) {
+                       if (path) {
+                               *path = file->f_path;
+                               path_get(&file->f_path);
+                       }
+                       if (info)
+                               snprintf(info, PROC_FDINFO_MAX,
+                                        "pos:\t%lli\n"
+                                        "flags:\t0%o\n",
+                                        (long long) file->f_pos,
+                                        file->f_flags);
+                       spin_unlock(&files->file_lock);
+                       put_files_struct(files);
+                       return 0;
                }
+               spin_unlock(&files->file_lock);
+               put_files_struct(files);
        }
-       rcu_read_unlock();
-       return 0;
+       return -ENOENT;
+}
+
+static int proc_fd_link(struct inode *inode, struct path *path)
+{
+       return proc_fd_info(inode, path, NULL);
 }
 
 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
@@ -1389,6 +1507,7 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
                                        inode->i_uid = 0;
                                        inode->i_gid = 0;
                                }
+                               inode->i_mode &= ~(S_ISUID | S_ISGID);
                                security_task_to_inode(task, inode);
                                put_task_struct(task);
                                return 1;
@@ -1402,75 +1521,30 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
        return 0;
 }
 
-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 !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
-}
-
 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,
-};
-
-/* 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)
+static struct dentry *proc_fd_instantiate(struct inode *dir,
+       struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
-       struct task_struct *task = get_proc_task(dir);
-       unsigned fd = name_to_int(dentry);
-       struct dentry *result = ERR_PTR(-ENOENT);
-       struct file * file;
-       struct files_struct * files;
-       struct inode *inode;
-       struct proc_inode *ei;
-
-       if (!task)
-               goto out_no_task;
-       if (fd == ~0U)
-               goto out;
+       unsigned fd = *(const unsigned *)ptr;
+       struct file *file;
+       struct files_struct *files;
+       struct inode *inode;
+       struct proc_inode *ei;
+       struct dentry *error = ERR_PTR(-ENOENT);
 
-       inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd);
+       inode = proc_pid_make_inode(dir->i_sb, task);
        if (!inode)
                goto out;
        ei = PROC_I(inode);
        ei->fd = fd;
        files = get_files_struct(task);
        if (!files)
-               goto out_unlock;
+               goto out_iput;
        inode->i_mode = S_IFLNK;
 
        /*
@@ -1480,13 +1554,14 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry,
        spin_lock(&files->file_lock);
        file = fcheck_files(files, fd);
        if (!file)
-               goto out_unlock2;
+               goto out_unlock;
        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;
@@ -1494,90 +1569,373 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry,
        d_add(dentry, inode);
        /* Close the race of the process dying before we return the dentry */
        if (tid_fd_revalidate(dentry, NULL))
-               result = NULL;
-out:
-       put_task_struct(task);
-out_no_task:
-       return result;
+               error = NULL;
 
-out_unlock2:
-       spin_unlock(&files->file_lock);
-       put_files_struct(files);
+ out:
+       return error;
 out_unlock:
+       spin_unlock(&files->file_lock);
+       put_files_struct(files);
+out_iput:
        iput(inode);
        goto out;
 }
 
-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 int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
+static struct dentry *proc_lookupfd_common(struct inode *dir,
+                                          struct dentry *dentry,
+                                          instantiate_t instantiate)
+{
+       struct task_struct *task = get_proc_task(dir);
+       unsigned fd = name_to_int(dentry);
+       struct dentry *result = ERR_PTR(-ENOENT);
+
+       if (!task)
+               goto out_no_task;
+       if (fd == ~0U)
+               goto out;
 
-static struct file_operations proc_fd_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_readfd,
+       result = instantiate(dir, dentry, task, &fd);
+out:
+       put_task_struct(task);
+out_no_task:
+       return result;
+}
+
+static int proc_readfd_common(struct file * filp, void * dirent,
+                             filldir_t filldir, instantiate_t instantiate)
+{
+       struct dentry *dentry = filp->f_path.dentry;
+       struct inode *inode = dentry->d_inode;
+       struct task_struct *p = get_proc_task(inode);
+       unsigned int fd, ino;
+       int retval;
+       struct files_struct * files;
+       struct fdtable *fdt;
+
+       retval = -ENOENT;
+       if (!p)
+               goto out_no_task;
+       retval = 0;
+
+       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 = parent_ino(dentry);
+                       if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
+                               goto out;
+                       filp->f_pos++;
+               default:
+                       files = get_files_struct(p);
+                       if (!files)
+                               goto out;
+                       rcu_read_lock();
+                       fdt = files_fdtable(files);
+                       for (fd = filp->f_pos-2;
+                            fd < fdt->max_fds;
+                            fd++, filp->f_pos++) {
+                               char name[PROC_NUMBUF];
+                               int len;
+
+                               if (!fcheck_files(files, fd))
+                                       continue;
+                               rcu_read_unlock();
+
+                               len = snprintf(name, sizeof(name), "%d", fd);
+                               if (proc_fill_cache(filp, dirent, filldir,
+                                                   name, len, instantiate,
+                                                   p, &fd) < 0) {
+                                       rcu_read_lock();
+                                       break;
+                               }
+                               rcu_read_lock();
+                       }
+                       rcu_read_unlock();
+                       put_files_struct(files);
+       }
+out:
+       put_task_struct(p);
+out_no_task:
+       return retval;
+}
+
+static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
+                                   struct nameidata *nd)
+{
+       return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
+}
+
+static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
+{
+       return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
+}
+
+static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
+                                     size_t len, loff_t *ppos)
+{
+       char tmp[PROC_FDINFO_MAX];
+       int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
+       if (!err)
+               err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
+       return err;
+}
+
+static const struct file_operations proc_fdinfo_file_operations = {
+       .open           = nonseekable_open,
+       .read           = proc_fdinfo_read,
 };
 
-static struct file_operations proc_task_operations = {
+static const struct file_operations proc_fd_operations = {
        .read           = generic_read_dir,
-       .readdir        = proc_task_readdir,
+       .readdir        = proc_readfd,
 };
 
+/*
+ * /proc/pid/fd needs a special permission handler so that a process can still
+ * access /proc/self/fd after it has executed a setuid().
+ */
+static int proc_fd_permission(struct inode *inode, int mask,
+                               struct nameidata *nd)
+{
+       int rv;
+
+       rv = generic_permission(inode, mask, NULL);
+       if (rv == 0)
+               return 0;
+       if (task_pid(current) == proc_pid(inode))
+               rv = 0;
+       return rv;
+}
+
 /*
  * proc directories can do almost nothing..
  */
-static struct inode_operations proc_fd_inode_operations = {
+static const struct inode_operations proc_fd_inode_operations = {
        .lookup         = proc_lookupfd,
+       .permission     = proc_fd_permission,
+       .setattr        = proc_setattr,
 };
 
-static struct inode_operations proc_task_inode_operations = {
-       .lookup         = proc_task_lookup,
-       .getattr        = proc_task_getattr,
+static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
+       struct dentry *dentry, struct task_struct *task, const void *ptr)
+{
+       unsigned fd = *(unsigned *)ptr;
+       struct inode *inode;
+       struct proc_inode *ei;
+       struct dentry *error = ERR_PTR(-ENOENT);
+
+       inode = proc_pid_make_inode(dir->i_sb, task);
+       if (!inode)
+               goto out;
+       ei = PROC_I(inode);
+       ei->fd = fd;
+       inode->i_mode = S_IFREG | S_IRUSR;
+       inode->i_fop = &proc_fdinfo_file_operations;
+       dentry->d_op = &tid_fd_dentry_operations;
+       d_add(dentry, inode);
+       /* Close the race of the process dying before we return the dentry */
+       if (tid_fd_revalidate(dentry, NULL))
+               error = NULL;
+
+ out:
+       return error;
+}
+
+static struct dentry *proc_lookupfdinfo(struct inode *dir,
+                                       struct dentry *dentry,
+                                       struct nameidata *nd)
+{
+       return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
+}
+
+static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
+{
+       return proc_readfd_common(filp, dirent, filldir,
+                                 proc_fdinfo_instantiate);
+}
+
+static const struct file_operations proc_fdinfo_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_readfdinfo,
 };
 
-#ifdef CONFIG_SECURITY
-static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
-                                 size_t count, loff_t *ppos)
+/*
+ * proc directories can do almost nothing..
+ */
+static const struct inode_operations proc_fdinfo_inode_operations = {
+       .lookup         = proc_lookupfdinfo,
+       .setattr        = proc_setattr,
+};
+
+
+static struct dentry *proc_pident_instantiate(struct inode *dir,
+       struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
-       struct inode * inode = file->f_dentry->d_inode;
-       unsigned long page;
-       ssize_t length;
-       struct task_struct *task = get_proc_task(inode);
+       const struct pid_entry *p = ptr;
+       struct inode *inode;
+       struct proc_inode *ei;
+       struct dentry *error = ERR_PTR(-EINVAL);
+
+       inode = proc_pid_make_inode(dir->i_sb, task);
+       if (!inode)
+               goto out;
+
+       ei = PROC_I(inode);
+       inode->i_mode = p->mode;
+       if (S_ISDIR(inode->i_mode))
+               inode->i_nlink = 2;     /* Use getattr to fix if necessary */
+       if (p->iop)
+               inode->i_op = p->iop;
+       if (p->fop)
+               inode->i_fop = p->fop;
+       ei->op = p->op;
+       dentry->d_op = &pid_dentry_operations;
+       d_add(dentry, inode);
+       /* Close the race of the process dying before we return the dentry */
+       if (pid_revalidate(dentry, NULL))
+               error = NULL;
+out:
+       return error;
+}
+
+static struct dentry *proc_pident_lookup(struct inode *dir, 
+                                        struct dentry *dentry,
+                                        const struct pid_entry *ents,
+                                        unsigned int nents)
+{
+       struct inode *inode;
+       struct dentry *error;
+       struct task_struct *task = get_proc_task(dir);
+       const struct pid_entry *p, *last;
+
+       error = ERR_PTR(-ENOENT);
+       inode = NULL;
 
-       length = -ESRCH;
        if (!task)
                goto out_no_task;
 
-       if (count > PAGE_SIZE)
-               count = PAGE_SIZE;
-       length = -ENOMEM;
-       if (!(page = __get_free_page(GFP_KERNEL)))
+       /*
+        * Yes, it does not scale. And it should not. Don't add
+        * new entries into /proc/<tgid>/ without very good reasons.
+        */
+       last = &ents[nents - 1];
+       for (p = ents; p <= last; p++) {
+               if (p->len != dentry->d_name.len)
+                       continue;
+               if (!memcmp(dentry->d_name.name, p->name, p->len))
+                       break;
+       }
+       if (p > last)
                goto out;
 
-       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);
+       error = proc_pident_instantiate(dir, dentry, task, p);
+out:
+       put_task_struct(task);
+out_no_task:
+       return error;
+}
+
+static int proc_pident_fill_cache(struct file *filp, void *dirent,
+       filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
+{
+       return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
+                               proc_pident_instantiate, task, p);
+}
+
+static int proc_pident_readdir(struct file *filp,
+               void *dirent, filldir_t filldir,
+               const struct pid_entry *ents, unsigned int nents)
+{
+       int i;
+       struct dentry *dentry = filp->f_path.dentry;
+       struct inode *inode = dentry->d_inode;
+       struct task_struct *task = get_proc_task(inode);
+       const struct pid_entry *p, *last;
+       ino_t ino;
+       int ret;
+
+       ret = -ENOENT;
+       if (!task)
+               goto out_no_task;
+
+       ret = 0;
+       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;
+               last = &ents[nents - 1];
+               while (p <= last) {
+                       if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
+                               goto out;
+                       filp->f_pos++;
+                       p++;
+               }
+       }
+
+       ret = 1;
 out:
        put_task_struct(task);
 out_no_task:
+       return ret;
+}
+
+#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_path.dentry->d_inode;
+       char *p = NULL;
+       ssize_t length;
+       struct task_struct *task = get_proc_task(inode);
+
+       if (!task)
+               return -ESRCH;
+
+       length = security_getprocattr(task,
+                                     (char*)file->f_path.dentry->d_name.name,
+                                     &p);
+       put_task_struct(task);
+       if (length > 0)
+               length = simple_read_from_buffer(buf, count, ppos, p, length);
+       kfree(p);
        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 inode * inode = file->f_path.dentry->d_inode;
+       char *page;
+       ssize_t length;
        struct task_struct *task = get_proc_task(inode);
 
        length = -ESRCH;
        if (!task)
                goto out_no_task;
-       if (count > PAGE_SIZE) 
-               count = PAGE_SIZE; 
+       if (count > PAGE_SIZE)
+               count = PAGE_SIZE;
 
        /* No partial writes. */
        length = -EINVAL;
@@ -1585,16 +1943,16 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
                goto out;
 
        length = -ENOMEM;
-       page = (char*)__get_free_page(GFP_USER); 
-       if (!page) 
+       page = (char*)__get_free_page(GFP_TEMPORARY);
+       if (!page)
                goto out;
 
-       length = -EFAULT; 
-       if (copy_from_user(page, buf, count)) 
+       length = -EFAULT;
+       if (copy_from_user(page, buf, count))
                goto out_free;
 
-       length = security_setprocattr(task, 
-                                     (char*)file->f_dentry->d_name.name, 
+       length = security_setprocattr(task,
+                                     (char*)file->f_path.dentry->d_name.name,
                                      (void*)page, count);
 out_free:
        free_page((unsigned long) page);
@@ -1602,301 +1960,131 @@ out:
        put_task_struct(task);
 out_no_task:
        return length;
-} 
+}
 
-static struct file_operations proc_pid_attr_operations = {
+static const 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
+static const struct pid_entry attr_dir_stuff[] = {
+       REG("current",    S_IRUGO|S_IWUGO, pid_attr),
+       REG("prev",       S_IRUGO,         pid_attr),
+       REG("exec",       S_IRUGO|S_IWUGO, pid_attr),
+       REG("fscreate",   S_IRUGO|S_IWUGO, pid_attr),
+       REG("keycreate",  S_IRUGO|S_IWUGO, pid_attr),
+       REG("sockcreate", S_IRUGO|S_IWUGO, pid_attr),
+};
 
-/* SMP-safe */
-static struct dentry *proc_pident_lookup(struct inode *dir, 
-                                        struct dentry *dentry,
-                                        struct pid_entry *ents)
+static int proc_attr_dir_readdir(struct file * filp,
+                            void * dirent, filldir_t filldir)
 {
-       struct inode *inode;
-       struct dentry *error;
-       struct task_struct *task = get_proc_task(dir);
-       struct pid_entry *p;
-       struct proc_inode *ei;
-
-       error = ERR_PTR(-ENOENT);
-       inode = NULL;
-
-       if (!task)
-               goto out_no_task;
-
-       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 = ERR_PTR(-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 = 2;
-                       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;
-#ifdef CONFIG_NUMA
-               case PROC_TID_NUMA_MAPS:
-               case PROC_TGID_NUMA_MAPS:
-                       inode->i_fop = &proc_numa_maps_operations;
-                       break;
-#endif
-               case PROC_TID_MEM:
-               case PROC_TGID_MEM:
-                       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_MMU
-               case PROC_TID_SMAPS:
-               case PROC_TGID_SMAPS:
-                       inode->i_fop = &proc_smaps_operations;
-                       break;
-#endif
-               case PROC_TID_MOUNTSTATS:
-               case PROC_TGID_MOUNTSTATS:
-                       inode->i_fop = &proc_mountstats_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:
-               case PROC_TID_ATTR_KEYCREATE:
-               case PROC_TGID_ATTR_KEYCREATE:
-               case PROC_TID_ATTR_SOCKCREATE:
-               case PROC_TGID_ATTR_SOCKCREATE:
-                       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);
-                       error = ERR_PTR(-EINVAL);
-                       goto out;
-       }
-       dentry->d_op = &pid_dentry_operations;
-       d_add(dentry, inode);
-       /* Close the race of the process dying before we return the dentry */
-       if (pid_revalidate(dentry, NULL))
-               error = NULL;
-out:
-       put_task_struct(task);
-out_no_task:
-       return 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);
+       return proc_pident_readdir(filp,dirent,filldir,
+                                  attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
 }
 
-static struct file_operations proc_tgid_base_operations = {
+static const struct file_operations proc_attr_dir_operations = {
        .read           = generic_read_dir,
-       .readdir        = proc_tgid_base_readdir,
+       .readdir        = proc_attr_dir_readdir,
 };
 
-static struct file_operations proc_tid_base_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tid_base_readdir,
-};
+static struct dentry *proc_attr_dir_lookup(struct inode *dir,
+                               struct dentry *dentry, struct nameidata *nd)
+{
+       return proc_pident_lookup(dir, dentry,
+                                 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
+}
 
-static struct inode_operations proc_tgid_base_inode_operations = {
-       .lookup         = proc_tgid_base_lookup,
+static const struct inode_operations proc_attr_dir_inode_operations = {
+       .lookup         = proc_attr_dir_lookup,
        .getattr        = pid_getattr,
+       .setattr        = proc_setattr,
 };
 
-static struct inode_operations proc_tid_base_inode_operations = {
-       .lookup         = proc_tid_base_lookup,
-       .getattr        = pid_getattr,
-};
+#endif
 
-#ifdef CONFIG_SECURITY
-static int proc_tgid_attr_readdir(struct file * filp,
-                            void * dirent, filldir_t filldir)
+#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
+static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
+                                        size_t count, loff_t *ppos)
 {
-       return proc_pident_readdir(filp,dirent,filldir,
-                                  tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff));
-}
+       struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+       struct mm_struct *mm;
+       char buffer[PROC_NUMBUF];
+       size_t len;
+       int ret;
 
-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));
-}
+       if (!task)
+               return -ESRCH;
 
-static struct file_operations proc_tgid_attr_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tgid_attr_readdir,
-};
+       ret = 0;
+       mm = get_task_mm(task);
+       if (mm) {
+               len = snprintf(buffer, sizeof(buffer), "%08lx\n",
+                              ((mm->flags & MMF_DUMP_FILTER_MASK) >>
+                               MMF_DUMP_FILTER_SHIFT));
+               mmput(mm);
+               ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
+       }
 
-static struct file_operations proc_tid_attr_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tid_attr_readdir,
-};
+       put_task_struct(task);
 
-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);
+       return ret;
 }
 
-static struct dentry *proc_tid_attr_lookup(struct inode *dir,
-                               struct dentry *dentry, struct nameidata *nd)
+static ssize_t proc_coredump_filter_write(struct file *file,
+                                         const char __user *buf,
+                                         size_t count,
+                                         loff_t *ppos)
 {
-       return proc_pident_lookup(dir, dentry, tid_attr_stuff);
-}
+       struct task_struct *task;
+       struct mm_struct *mm;
+       char buffer[PROC_NUMBUF], *end;
+       unsigned int val;
+       int ret;
+       int i;
+       unsigned long mask;
 
-static struct inode_operations proc_tgid_attr_inode_operations = {
-       .lookup         = proc_tgid_attr_lookup,
-       .getattr        = pid_getattr,
-};
+       ret = -EFAULT;
+       memset(buffer, 0, sizeof(buffer));
+       if (count > sizeof(buffer) - 1)
+               count = sizeof(buffer) - 1;
+       if (copy_from_user(buffer, buf, count))
+               goto out_no_task;
 
-static struct inode_operations proc_tid_attr_inode_operations = {
-       .lookup         = proc_tid_attr_lookup,
-       .getattr        = pid_getattr,
+       ret = -EINVAL;
+       val = (unsigned int)simple_strtoul(buffer, &end, 0);
+       if (*end == '\n')
+               end++;
+       if (end - buffer == 0)
+               goto out_no_task;
+
+       ret = -ESRCH;
+       task = get_proc_task(file->f_dentry->d_inode);
+       if (!task)
+               goto out_no_task;
+
+       ret = end - buffer;
+       mm = get_task_mm(task);
+       if (!mm)
+               goto out_no_mm;
+
+       for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
+               if (val & mask)
+                       set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
+               else
+                       clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
+       }
+
+       mmput(mm);
+ out_no_mm:
+       put_task_struct(task);
+ out_no_task:
+       return ret;
+}
+
+static const struct file_operations proc_coredump_filter_operations = {
+       .read           = proc_coredump_filter_read,
+       .write          = proc_coredump_filter_write,
 };
 #endif
 
@@ -1906,65 +2094,289 @@ static struct inode_operations proc_tid_attr_inode_operations = {
 static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
                              int buflen)
 {
+       struct pid_namespace *ns = dentry->d_sb->s_fs_info;
+       pid_t tgid = task_tgid_nr_ns(current, ns);
        char tmp[PROC_NUMBUF];
-       sprintf(tmp, "%d", current->tgid);
+       if (!tgid)
+               return -ENOENT;
+       sprintf(tmp, "%d", tgid);
        return vfs_readlink(dentry,buffer,buflen,tmp);
 }
 
 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
+       struct pid_namespace *ns = dentry->d_sb->s_fs_info;
+       pid_t tgid = task_tgid_nr_ns(current, ns);
        char tmp[PROC_NUMBUF];
-       sprintf(tmp, "%d", current->tgid);
+       if (!tgid)
+               return ERR_PTR(-ENOENT);
+       sprintf(tmp, "%d", task_tgid_nr_ns(current, ns));
        return ERR_PTR(vfs_follow_link(nd,tmp));
-}      
+}
 
-static struct inode_operations proc_self_inode_operations = {
+static const struct inode_operations proc_self_inode_operations = {
        .readlink       = proc_self_readlink,
        .follow_link    = proc_self_follow_link,
 };
 
-/**
- * proc_flush_task -  Remove dcache entries for @task from the /proc dcache.
- *
- * @task: task that should be flushed.
- *
- * Looks in the dcache for
- * /proc/@pid
- * /proc/@tgid/task/@pid
- * if either directory is present flushes it and all of it'ts children
- * from the dcache.
- *
- * It is safe and reasonable to cache /proc entries for a task until
- * that task exits.  After that they just clog up the dcache with
- * useless entries, possibly causing useful dcache entries to be
- * flushed instead.  This routine is proved to flush those useless
- * dcache entries at process exit time.
+/*
+ * proc base
  *
- * NOTE: This routine is just an optimization so it does not guarantee
- *       that no dcache entries will exist at process exit time it
- *       just makes it very unlikely that any will persist.
+ * These are the directory entries in the root directory of /proc
+ * that properly belong to the /proc filesystem, as they describe
+ * describe something that is process related.
  */
-void proc_flush_task(struct task_struct *task)
+static const struct pid_entry proc_base_stuff[] = {
+       NOD("self", S_IFLNK|S_IRWXUGO,
+               &proc_self_inode_operations, NULL, {}),
+};
+
+/*
+ *     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.
+ */
+static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+       struct inode *inode = dentry->d_inode;
+       struct task_struct *task = get_proc_task(inode);
+       if (task) {
+               put_task_struct(task);
+               return 1;
+       }
+       d_drop(dentry);
+       return 0;
+}
+
+static struct dentry_operations proc_base_dentry_operations =
+{
+       .d_revalidate   = proc_base_revalidate,
+       .d_delete       = pid_delete_dentry,
+};
+
+static struct dentry *proc_base_instantiate(struct inode *dir,
+       struct dentry *dentry, struct task_struct *task, const void *ptr)
+{
+       const struct pid_entry *p = ptr;
+       struct inode *inode;
+       struct proc_inode *ei;
+       struct dentry *error = ERR_PTR(-EINVAL);
+
+       /* Allocate the inode */
+       error = ERR_PTR(-ENOMEM);
+       inode = new_inode(dir->i_sb);
+       if (!inode)
+               goto out;
+
+       /* Initialize the inode */
+       ei = PROC_I(inode);
+       inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+
+       /*
+        * grab the reference to the task.
+        */
+       ei->pid = get_task_pid(task, PIDTYPE_PID);
+       if (!ei->pid)
+               goto out_iput;
+
+       inode->i_uid = 0;
+       inode->i_gid = 0;
+       inode->i_mode = p->mode;
+       if (S_ISDIR(inode->i_mode))
+               inode->i_nlink = 2;
+       if (S_ISLNK(inode->i_mode))
+               inode->i_size = 64;
+       if (p->iop)
+               inode->i_op = p->iop;
+       if (p->fop)
+               inode->i_fop = p->fop;
+       ei->op = p->op;
+       dentry->d_op = &proc_base_dentry_operations;
+       d_add(dentry, inode);
+       error = NULL;
+out:
+       return error;
+out_iput:
+       iput(inode);
+       goto out;
+}
+
+static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
+{
+       struct dentry *error;
+       struct task_struct *task = get_proc_task(dir);
+       const struct pid_entry *p, *last;
+
+       error = ERR_PTR(-ENOENT);
+
+       if (!task)
+               goto out_no_task;
+
+       /* Lookup the directory entry */
+       last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
+       for (p = proc_base_stuff; p <= last; p++) {
+               if (p->len != dentry->d_name.len)
+                       continue;
+               if (!memcmp(dentry->d_name.name, p->name, p->len))
+                       break;
+       }
+       if (p > last)
+               goto out;
+
+       error = proc_base_instantiate(dir, dentry, task, p);
+
+out:
+       put_task_struct(task);
+out_no_task:
+       return error;
+}
+
+static int proc_base_fill_cache(struct file *filp, void *dirent,
+       filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
+{
+       return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
+                               proc_base_instantiate, task, p);
+}
+
+#ifdef CONFIG_TASK_IO_ACCOUNTING
+static int proc_pid_io_accounting(struct task_struct *task, char *buffer)
+{
+       return sprintf(buffer,
+#ifdef CONFIG_TASK_XACCT
+                       "rchar: %llu\n"
+                       "wchar: %llu\n"
+                       "syscr: %llu\n"
+                       "syscw: %llu\n"
+#endif
+                       "read_bytes: %llu\n"
+                       "write_bytes: %llu\n"
+                       "cancelled_write_bytes: %llu\n",
+#ifdef CONFIG_TASK_XACCT
+                       (unsigned long long)task->rchar,
+                       (unsigned long long)task->wchar,
+                       (unsigned long long)task->syscr,
+                       (unsigned long long)task->syscw,
+#endif
+                       (unsigned long long)task->ioac.read_bytes,
+                       (unsigned long long)task->ioac.write_bytes,
+                       (unsigned long long)task->ioac.cancelled_write_bytes);
+}
+#endif
+
+/*
+ * Thread groups
+ */
+static const struct file_operations proc_task_operations;
+static const struct inode_operations proc_task_inode_operations;
+
+static const struct pid_entry tgid_base_stuff[] = {
+       DIR("task",       S_IRUGO|S_IXUGO, task),
+       DIR("fd",         S_IRUSR|S_IXUSR, fd),
+       DIR("fdinfo",     S_IRUSR|S_IXUSR, fdinfo),
+       REG("environ",    S_IRUSR, environ),
+       INF("auxv",       S_IRUSR, pid_auxv),
+       ONE("status",     S_IRUGO, pid_status),
+       INF("limits",     S_IRUSR, pid_limits),
+#ifdef CONFIG_SCHED_DEBUG
+       REG("sched",      S_IRUGO|S_IWUSR, pid_sched),
+#endif
+       INF("cmdline",    S_IRUGO, pid_cmdline),
+       ONE("stat",       S_IRUGO, tgid_stat),
+       ONE("statm",      S_IRUGO, pid_statm),
+       REG("maps",       S_IRUGO, maps),
+#ifdef CONFIG_NUMA
+       REG("numa_maps",  S_IRUGO, numa_maps),
+#endif
+       REG("mem",        S_IRUSR|S_IWUSR, mem),
+       LNK("cwd",        cwd),
+       LNK("root",       root),
+       LNK("exe",        exe),
+       REG("mounts",     S_IRUGO, mounts),
+       REG("mountstats", S_IRUSR, mountstats),
+#ifdef CONFIG_PROC_PAGE_MONITOR
+       REG("clear_refs", S_IWUSR, clear_refs),
+       REG("smaps",      S_IRUGO, smaps),
+       REG("pagemap",    S_IRUSR, pagemap),
+#endif
+#ifdef CONFIG_SECURITY
+       DIR("attr",       S_IRUGO|S_IXUGO, attr_dir),
+#endif
+#ifdef CONFIG_KALLSYMS
+       INF("wchan",      S_IRUGO, pid_wchan),
+#endif
+#ifdef CONFIG_SCHEDSTATS
+       INF("schedstat",  S_IRUGO, pid_schedstat),
+#endif
+#ifdef CONFIG_LATENCYTOP
+       REG("latency",  S_IRUGO, lstats),
+#endif
+#ifdef CONFIG_PROC_PID_CPUSET
+       REG("cpuset",     S_IRUGO, cpuset),
+#endif
+#ifdef CONFIG_CGROUPS
+       REG("cgroup",  S_IRUGO, cgroup),
+#endif
+       INF("oom_score",  S_IRUGO, oom_score),
+       REG("oom_adj",    S_IRUGO|S_IWUSR, oom_adjust),
+#ifdef CONFIG_AUDITSYSCALL
+       REG("loginuid",   S_IWUSR|S_IRUGO, loginuid),
+#endif
+#ifdef CONFIG_FAULT_INJECTION
+       REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
+#endif
+#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
+       REG("coredump_filter", S_IRUGO|S_IWUSR, coredump_filter),
+#endif
+#ifdef CONFIG_TASK_IO_ACCOUNTING
+       INF("io",       S_IRUGO, pid_io_accounting),
+#endif
+};
+
+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 const struct file_operations proc_tgid_base_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_tgid_base_readdir,
+};
+
+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, ARRAY_SIZE(tgid_base_stuff));
+}
+
+static const struct inode_operations proc_tgid_base_inode_operations = {
+       .lookup         = proc_tgid_base_lookup,
+       .getattr        = pid_getattr,
+       .setattr        = proc_setattr,
+};
+
+static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
 {
        struct dentry *dentry, *leader, *dir;
        char buf[PROC_NUMBUF];
        struct qstr name;
 
        name.name = buf;
-       name.len = snprintf(buf, sizeof(buf), "%d", task->pid);
-       dentry = d_hash_and_lookup(proc_mnt->mnt_root, &name);
+       name.len = snprintf(buf, sizeof(buf), "%d", pid);
+       dentry = d_hash_and_lookup(mnt->mnt_root, &name);
        if (dentry) {
-               shrink_dcache_parent(dentry);
+               if (!(current->flags & PF_EXITING))
+                       shrink_dcache_parent(dentry);
                d_drop(dentry);
                dput(dentry);
        }
 
-       if (thread_group_leader(task))
+       if (tgid == 0)
                goto out;
 
        name.name = buf;
-       name.len = snprintf(buf, sizeof(buf), "%d", task->tgid);
-       leader = d_hash_and_lookup(proc_mnt->mnt_root, &name);
+       name.len = snprintf(buf, sizeof(buf), "%d", tgid);
+       leader = d_hash_and_lookup(mnt->mnt_root, &name);
        if (!leader)
                goto out;
 
@@ -1975,7 +2387,7 @@ void proc_flush_task(struct task_struct *task)
                goto out_put_leader;
 
        name.name = buf;
-       name.len = snprintf(buf, sizeof(buf), "%d", task->pid);
+       name.len = snprintf(buf, sizeof(buf), "%d", pid);
        dentry = d_hash_and_lookup(dir, &name);
        if (dentry) {
                shrink_dcache_parent(dentry);
@@ -1990,54 +2402,70 @@ out:
        return;
 }
 
-/* SMP-safe */
-struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
+/**
+ * proc_flush_task -  Remove dcache entries for @task from the /proc dcache.
+ * @task: task that should be flushed.
+ *
+ * When flushing dentries from proc, one needs to flush them from global
+ * proc (proc_mnt) and from all the namespaces' procs this task was seen
+ * in. This call is supposed to do all of this job.
+ *
+ * Looks in the dcache for
+ * /proc/@pid
+ * /proc/@tgid/task/@pid
+ * if either directory is present flushes it and all of it'ts children
+ * from the dcache.
+ *
+ * It is safe and reasonable to cache /proc entries for a task until
+ * that task exits.  After that they just clog up the dcache with
+ * useless entries, possibly causing useful dcache entries to be
+ * flushed instead.  This routine is proved to flush those useless
+ * dcache entries at process exit time.
+ *
+ * NOTE: This routine is just an optimization so it does not guarantee
+ *       that no dcache entries will exist at process exit time it
+ *       just makes it very unlikely that any will persist.
+ */
+
+void proc_flush_task(struct task_struct *task)
 {
-       struct dentry *result = ERR_PTR(-ENOENT);
-       struct task_struct *task;
-       struct inode *inode;
-       struct proc_inode *ei;
-       unsigned tgid;
+       int i;
+       struct pid *pid, *tgid = NULL;
+       struct upid *upid;
 
-       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;
+       pid = task_pid(task);
+       if (thread_group_leader(task))
+               tgid = task_tgid(task);
+
+       for (i = 0; i <= pid->level; i++) {
+               upid = &pid->numbers[i];
+               proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
+                       tgid ? tgid->numbers[i].nr : 0);
        }
-       tgid = name_to_int(dentry);
-       if (tgid == ~0U)
-               goto out;
 
-       rcu_read_lock();
-       task = find_task_by_pid(tgid);
-       if (task)
-               get_task_struct(task);
-       rcu_read_unlock();
-       if (!task)
-               goto out;
+       upid = &pid->numbers[pid->level];
+       if (upid->nr == 1)
+               pid_ns_release_proc(upid->ns);
+}
+
+static struct dentry *proc_pid_instantiate(struct inode *dir,
+                                          struct dentry * dentry,
+                                          struct task_struct *task, const void *ptr)
+{
+       struct dentry *error = ERR_PTR(-ENOENT);
+       struct inode *inode;
 
-       inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);
+       inode = proc_pid_make_inode(dir->i_sb, task);
        if (!inode)
-               goto out_put_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_flags|=S_IMMUTABLE;
-#ifdef CONFIG_SECURITY
        inode->i_nlink = 5;
-#else
-       inode->i_nlink = 4;
+#ifdef CONFIG_SECURITY
+       inode->i_nlink += 1;
 #endif
 
        dentry->d_op = &pid_dentry_operations;
@@ -2045,178 +2473,275 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct
        d_add(dentry, inode);
        /* Close the race of the process dying before we return the dentry */
        if (pid_revalidate(dentry, NULL))
-               result = NULL;
-
-out_put_task:
-       put_task_struct(task);
+               error = NULL;
 out:
-       return result;
+       return error;
 }
 
-/* SMP-safe */
-static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
+struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
 {
        struct dentry *result = ERR_PTR(-ENOENT);
        struct task_struct *task;
-       struct task_struct *leader = get_proc_task(dir);
-       struct inode *inode;
-       unsigned tid;
+       unsigned tgid;
+       struct pid_namespace *ns;
 
-       if (!leader)
-               goto out_no_task;
+       result = proc_base_lookup(dir, dentry);
+       if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
+               goto out;
 
-       tid = name_to_int(dentry);
-       if (tid == ~0U)
+       tgid = name_to_int(dentry);
+       if (tgid == ~0U)
                goto out;
 
+       ns = dentry->d_sb->s_fs_info;
        rcu_read_lock();
-       task = find_task_by_pid(tid);
+       task = find_task_by_pid_ns(tgid, ns);
        if (task)
                get_task_struct(task);
        rcu_read_unlock();
        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_flags|=S_IMMUTABLE;
-#ifdef CONFIG_SECURITY
-       inode->i_nlink = 4;
-#else
-       inode->i_nlink = 3;
-#endif
 
-       dentry->d_op = &pid_dentry_operations;
-
-       d_add(dentry, inode);
-       /* Close the race of the process dying before we return the dentry */
-       if (pid_revalidate(dentry, NULL))
-               result = NULL;
-
-out_drop_task:
+       result = proc_pid_instantiate(dir, dentry, task, NULL);
        put_task_struct(task);
 out:
-       put_task_struct(leader);
-out_no_task:
        return result;
 }
 
 /*
- * Find the first tgid to return to user space.
- *
- * Usually this is just whatever follows &init_task, but if the users
- * buffer was too small to hold the full list or there was a seek into
- * the middle of the directory we have more work to do.
- *
- * In the case of a short read we start with find_task_by_pid.
+ * Find the first task with tgid >= tgid
  *
- * In the case of a seek we start with &init_task and walk nr
- * threads past it.
  */
-static struct task_struct *first_tgid(int tgid, unsigned int nr)
+struct tgid_iter {
+       unsigned int tgid;
+       struct task_struct *task;
+};
+static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
 {
-       struct task_struct *pos;
-       rcu_read_lock();
-       if (tgid && nr) {
-               pos = find_task_by_pid(tgid);
-               if (pos && thread_group_leader(pos))
-                       goto found;
-       }
-       /* If nr exceeds the number of processes get out quickly */
-       pos = NULL;
-       if (nr && nr >= nr_processes())
-               goto done;
+       struct pid *pid;
 
-       /* If we haven't found our starting place yet start with
-        * the init_task and walk nr tasks forward.
-        */
-       for (pos = next_task(&init_task); nr > 0; --nr) {
-               pos = next_task(pos);
-               if (pos == &init_task) {
-                       pos = NULL;
-                       goto done;
+       if (iter.task)
+               put_task_struct(iter.task);
+       rcu_read_lock();
+retry:
+       iter.task = NULL;
+       pid = find_ge_pid(iter.tgid, ns);
+       if (pid) {
+               iter.tgid = pid_nr_ns(pid, ns);
+               iter.task = pid_task(pid, PIDTYPE_PID);
+               /* What we to know is if the pid we have find is the
+                * pid of a thread_group_leader.  Testing for task
+                * being a thread_group_leader is the obvious thing
+                * todo but there is a window when it fails, due to
+                * the pid transfer logic in de_thread.
+                *
+                * So we perform the straight forward test of seeing
+                * if the pid we have found is the pid of a thread
+                * group leader, and don't worry if the task we have
+                * found doesn't happen to be a thread group leader.
+                * As we don't care in the case of readdir.
+                */
+               if (!iter.task || !has_group_leader_pid(iter.task)) {
+                       iter.tgid += 1;
+                       goto retry;
                }
+               get_task_struct(iter.task);
        }
-found:
-       get_task_struct(pos);
-done:
        rcu_read_unlock();
-       return pos;
+       return iter;
 }
 
-/*
- * Find the next task in the task list.
- * Return NULL if we loop or there is any error.
- *
- * The reference to the input task_struct is released.
- */
-static struct task_struct *next_tgid(struct task_struct *start)
+#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
+
+static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
+       struct tgid_iter iter)
 {
-       struct task_struct *pos;
-       rcu_read_lock();
-       pos = start;
-       if (pid_alive(start))
-               pos = next_task(start);
-       if (pid_alive(pos) && (pos != &init_task)) {
-               get_task_struct(pos);
-               goto done;
-       }
-       pos = NULL;
-done:
-       rcu_read_unlock();
-       put_task_struct(start);
-       return pos;
+       char name[PROC_NUMBUF];
+       int len = snprintf(name, sizeof(name), "%d", iter.tgid);
+       return proc_fill_cache(filp, dirent, filldir, name, len,
+                               proc_pid_instantiate, iter.task, NULL);
 }
 
 /* for the /proc/ directory itself, after non-process stuff has been done */
 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
 {
-       char buf[PROC_NUMBUF];
        unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
-       struct task_struct *task;
-       int tgid;
+       struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
+       struct tgid_iter iter;
+       struct pid_namespace *ns;
 
-       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++;
+       if (!reaper)
+               goto out_no_task;
+
+       for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
+               const struct pid_entry *p = &proc_base_stuff[nr];
+               if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
+                       goto out;
        }
-       nr -= 1;
 
-       /* f_version caches the tgid value that the last readdir call couldn't
-        * return. lseek aka telldir automagically resets f_version to 0.
-        */
-       tgid = filp->f_version;
-       filp->f_version = 0;
-       for (task = first_tgid(tgid, nr);
-            task;
-            task = next_tgid(task), filp->f_pos++) {
-               int len;
-               ino_t ino;
-               tgid = task->pid;
-               len = snprintf(buf, sizeof(buf), "%d", tgid);
-               ino = fake_ino(tgid, PROC_TGID_INO);
-               if (filldir(dirent, buf, len, 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;
-                       put_task_struct(task);
-                       break;
+       ns = filp->f_dentry->d_sb->s_fs_info;
+       iter.task = NULL;
+       iter.tgid = filp->f_pos - TGID_OFFSET;
+       for (iter = next_tgid(ns, iter);
+            iter.task;
+            iter.tgid += 1, iter = next_tgid(ns, iter)) {
+               filp->f_pos = iter.tgid + TGID_OFFSET;
+               if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
+                       put_task_struct(iter.task);
+                       goto out;
                }
        }
+       filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
+out:
+       put_task_struct(reaper);
+out_no_task:
        return 0;
 }
 
+/*
+ * Tasks
+ */
+static const struct pid_entry tid_base_stuff[] = {
+       DIR("fd",        S_IRUSR|S_IXUSR, fd),
+       DIR("fdinfo",    S_IRUSR|S_IXUSR, fdinfo),
+       REG("environ",   S_IRUSR, environ),
+       INF("auxv",      S_IRUSR, pid_auxv),
+       ONE("status",    S_IRUGO, pid_status),
+       INF("limits",    S_IRUSR, pid_limits),
+#ifdef CONFIG_SCHED_DEBUG
+       REG("sched",     S_IRUGO|S_IWUSR, pid_sched),
+#endif
+       INF("cmdline",   S_IRUGO, pid_cmdline),
+       ONE("stat",      S_IRUGO, tid_stat),
+       ONE("statm",     S_IRUGO, pid_statm),
+       REG("maps",      S_IRUGO, maps),
+#ifdef CONFIG_NUMA
+       REG("numa_maps", S_IRUGO, numa_maps),
+#endif
+       REG("mem",       S_IRUSR|S_IWUSR, mem),
+       LNK("cwd",       cwd),
+       LNK("root",      root),
+       LNK("exe",       exe),
+       REG("mounts",    S_IRUGO, mounts),
+#ifdef CONFIG_PROC_PAGE_MONITOR
+       REG("clear_refs", S_IWUSR, clear_refs),
+       REG("smaps",     S_IRUGO, smaps),
+       REG("pagemap",    S_IRUSR, pagemap),
+#endif
+#ifdef CONFIG_SECURITY
+       DIR("attr",      S_IRUGO|S_IXUGO, attr_dir),
+#endif
+#ifdef CONFIG_KALLSYMS
+       INF("wchan",     S_IRUGO, pid_wchan),
+#endif
+#ifdef CONFIG_SCHEDSTATS
+       INF("schedstat", S_IRUGO, pid_schedstat),
+#endif
+#ifdef CONFIG_LATENCYTOP
+       REG("latency",  S_IRUGO, lstats),
+#endif
+#ifdef CONFIG_PROC_PID_CPUSET
+       REG("cpuset",    S_IRUGO, cpuset),
+#endif
+#ifdef CONFIG_CGROUPS
+       REG("cgroup",  S_IRUGO, cgroup),
+#endif
+       INF("oom_score", S_IRUGO, oom_score),
+       REG("oom_adj",   S_IRUGO|S_IWUSR, oom_adjust),
+#ifdef CONFIG_AUDITSYSCALL
+       REG("loginuid",  S_IWUSR|S_IRUGO, loginuid),
+#endif
+#ifdef CONFIG_FAULT_INJECTION
+       REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
+#endif
+};
+
+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));
+}
+
+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, ARRAY_SIZE(tid_base_stuff));
+}
+
+static const struct file_operations proc_tid_base_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_tid_base_readdir,
+};
+
+static const struct inode_operations proc_tid_base_inode_operations = {
+       .lookup         = proc_tid_base_lookup,
+       .getattr        = pid_getattr,
+       .setattr        = proc_setattr,
+};
+
+static struct dentry *proc_task_instantiate(struct inode *dir,
+       struct dentry *dentry, struct task_struct *task, const void *ptr)
+{
+       struct dentry *error = ERR_PTR(-ENOENT);
+       struct inode *inode;
+       inode = proc_pid_make_inode(dir->i_sb, task);
+
+       if (!inode)
+               goto out;
+       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_flags|=S_IMMUTABLE;
+       inode->i_nlink = 4;
+#ifdef CONFIG_SECURITY
+       inode->i_nlink += 1;
+#endif
+
+       dentry->d_op = &pid_dentry_operations;
+
+       d_add(dentry, inode);
+       /* Close the race of the process dying before we return the dentry */
+       if (pid_revalidate(dentry, NULL))
+               error = NULL;
+out:
+       return error;
+}
+
+static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
+{
+       struct dentry *result = ERR_PTR(-ENOENT);
+       struct task_struct *task;
+       struct task_struct *leader = get_proc_task(dir);
+       unsigned tid;
+       struct pid_namespace *ns;
+
+       if (!leader)
+               goto out_no_task;
+
+       tid = name_to_int(dentry);
+       if (tid == ~0U)
+               goto out;
+
+       ns = dentry->d_sb->s_fs_info;
+       rcu_read_lock();
+       task = find_task_by_pid_ns(tid, ns);
+       if (task)
+               get_task_struct(task);
+       rcu_read_unlock();
+       if (!task)
+               goto out;
+       if (!same_thread_group(leader, task))
+               goto out_drop_task;
+
+       result = proc_task_instantiate(dir, dentry, task, NULL);
+out_drop_task:
+       put_task_struct(task);
+out:
+       put_task_struct(leader);
+out_no_task:
+       return result;
+}
+
 /*
  * Find the first tid of a thread group to return to user space.
  *
@@ -2230,14 +2755,14 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
  * threads past it.
  */
 static struct task_struct *first_tid(struct task_struct *leader,
-                                       int tid, int nr)
+               int tid, int nr, struct pid_namespace *ns)
 {
        struct task_struct *pos;
 
        rcu_read_lock();
        /* Attempt to start with the pid of a thread */
        if (tid && (nr > 0)) {
-               pos = find_task_by_pid(tid);
+               pos = find_task_by_pid_ns(tid, ns);
                if (pos && (pos->group_leader == leader))
                        goto found;
        }
@@ -2286,19 +2811,38 @@ static struct task_struct *next_tid(struct task_struct *start)
        return pos;
 }
 
+static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
+       struct task_struct *task, int tid)
+{
+       char name[PROC_NUMBUF];
+       int len = snprintf(name, sizeof(name), "%d", tid);
+       return proc_fill_cache(filp, dirent, filldir, name, len,
+                               proc_task_instantiate, task, NULL);
+}
+
 /* for the /proc/TGID/task/ directories */
 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
 {
-       char buf[PROC_NUMBUF];
-       struct dentry *dentry = filp->f_dentry;
+       struct dentry *dentry = filp->f_path.dentry;
        struct inode *inode = dentry->d_inode;
-       struct task_struct *leader = get_proc_task(inode);
+       struct task_struct *leader = NULL;
        struct task_struct *task;
        int retval = -ENOENT;
        ino_t ino;
        int tid;
        unsigned long pos = filp->f_pos;  /* avoiding "long long" filp->f_pos */
+       struct pid_namespace *ns;
 
+       task = get_proc_task(inode);
+       if (!task)
+               goto out_no_task;
+       rcu_read_lock();
+       if (pid_alive(task)) {
+               leader = task->group_leader;
+               get_task_struct(leader);
+       }
+       rcu_read_unlock();
+       put_task_struct(task);
        if (!leader)
                goto out_no_task;
        retval = 0;
@@ -2321,19 +2865,17 @@ static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldi
        /* f_version caches the tgid value that the last readdir call couldn't
         * return. lseek aka telldir automagically resets f_version to 0.
         */
-       tid = filp->f_version;
+       ns = filp->f_dentry->d_sb->s_fs_info;
+       tid = (int)filp->f_version;
        filp->f_version = 0;
-       for (task = first_tid(leader, tid, pos - 2);
+       for (task = first_tid(leader, tid, pos - 2, ns);
             task;
             task = next_tid(task), pos++) {
-               int len;
-               tid = task->pid;
-               len = snprintf(buf, sizeof(buf), "%d", tid);
-               ino = fake_ino(tid, PROC_TID_INO);
-               if (filldir(dirent, buf, len, pos, ino, DT_DIR < 0)) {
+               tid = task_pid_nr_ns(task, ns);
+               if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
                        /* returning this tgid failed, save it as the first
                         * pid for the next readir call */
-                       filp->f_version = tid;
+                       filp->f_version = (u64)tid;
                        put_task_struct(task);
                        break;
                }
@@ -2360,3 +2902,14 @@ static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct
 
        return 0;
 }
+
+static const struct inode_operations proc_task_inode_operations = {
+       .lookup         = proc_task_lookup,
+       .getattr        = proc_task_getattr,
+       .setattr        = proc_setattr,
+};
+
+static const struct file_operations proc_task_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_task_readdir,
+};