Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-serial
[pandora-kernel.git] / fs / proc / base.c
index 474eae3..82da55b 100644 (file)
@@ -71,6 +71,7 @@
 #include <linux/cpuset.h>
 #include <linux/audit.h>
 #include <linux/poll.h>
+#include <linux/nsproxy.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;
        mode_t mode;
+       struct inode_operations *iop;
+       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) {                        \
+       .len  = sizeof(NAME) - 1,                       \
+       .name = (NAME),                                 \
+       .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 } )
+
 static struct fs_struct *get_fs_struct(struct task_struct *task)
 {
        struct fs_struct *fs;
@@ -551,6 +334,27 @@ static int proc_fd_access_allowed(struct inode *inode)
        return allowed;
 }
 
+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 = security_inode_setattr(dentry, attr);
+               if (!error)
+                       error = inode_setattr(inode, attr);
+       }
+       return error;
+}
+
+static struct inode_operations proc_def_inode_operations = {
+       .setattr        = proc_setattr,
+};
+
 extern struct seq_operations mounts_op;
 struct proc_mounts {
        struct seq_file m;
@@ -566,7 +370,7 @@ static int mounts_open(struct inode *inode, struct file *file)
 
        if (task) {
                task_lock(task);
-               namespace = task->namespace;
+               namespace = task->nsproxy->namespace;
                if (namespace)
                        get_namespace(namespace);
                task_unlock(task);
@@ -637,7 +441,7 @@ static int mountstats_open(struct inode *inode, struct file *file)
 
                if (task) {
                        task_lock(task);
-                       namespace = task->namespace;
+                       namespace = task->nsproxy->namespace;
                        if (namespace)
                                get_namespace(namespace);
                        task_unlock(task);
@@ -776,7 +580,7 @@ out_no_task:
 static ssize_t mem_write(struct file * file, const char * 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);
        unsigned long dst = *ppos;
@@ -793,6 +597,7 @@ static ssize_t mem_write(struct file * file, const char * buf,
        if (!page)
                goto out;
 
+       copied = 0;
        while (count > 0) {
                int this_len, retval;
 
@@ -1111,146 +916,10 @@ out:
 
 static 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)
-{
-       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;
-
-       retval = -ENOENT;
-       if (!p)
-               goto out_no_task;
-       retval = 0;
-       tid = p->pid;
-
-       fd = filp->f_pos;
-       switch (fd) {
-               case 0:
-                       if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
-                               goto out;
-                       filp->f_pos++;
-               case 1:
-                       ino = 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();
-
-                               j = PROC_NUMBUF;
-                               i = fd;
-                               do {
-                                       j--;
-                                       buf[j] = '0' + (i % 10);
-                                       i /= 10;
-                               } while (i);
-
-                               ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
-                               if (filldir(dirent, buf+j, PROC_NUMBUF-j, fd+2, ino, DT_LNK) < 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 int proc_pident_readdir(struct file *filp,
-               void *dirent, filldir_t filldir,
-               struct pid_entry *ents, unsigned int nents)
-{
-       int i;
-       int pid;
-       struct dentry *dentry = filp->f_dentry;
-       struct inode *inode = dentry->d_inode;
-       struct task_struct *task = get_proc_task(inode);
-       struct pid_entry *p;
-       ino_t ino;
-       int ret;
-
-       ret = -ENOENT;
-       if (!task)
-               goto out;
-
-       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++;
-               }
-       }
-
-       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 */
 
@@ -1270,13 +939,13 @@ static int task_dumpable(struct task_struct *task)
 }
 
 
-static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino)
+static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
 {
        struct inode * inode;
        struct proc_inode *ei;
 
        /* We need a new inode */
-       
+
        inode = new_inode(sb);
        if (!inode)
                goto out;
@@ -1284,12 +953,12 @@ static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_st
        /* 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);
+       inode->i_op = &proc_def_inode_operations;
 
        /*
         * grab the reference to task.
         */
-       ei->pid = get_pid(task->pids[PIDTYPE_PID].pid);
+       ei->pid = get_task_pid(task, PIDTYPE_PID);
        if (!ei->pid)
                goto out_unlock;
 
@@ -1309,19 +978,40 @@ out_unlock:
        return NULL;
 }
 
-/* dentry stuff */
+static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+{
+       struct inode *inode = dentry->d_inode;
+       struct task_struct *task;
+       generic_fillattr(inode, stat);
 
-/*
- *     Exceptional case: normally we are not allowed to unhash a busy
- * directory. In this case, however, we can do it - no aliasing problems
- * due to the way we treat inodes.
- *
- * Rewrite the inode's ownerships here because the owning task may have
- * performed a setuid(), etc.
- *
- * Before the /proc/pid/status file was created the only way to read
- * the effective uid of a /process was to stat /proc/pid.  Reading
- * /proc/pid/status is slow enough that procps and other packages
+       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;
+               }
+       }
+       rcu_read_unlock();
+       return 0;
+}
+
+/* dentry stuff */
+
+/*
+ *     Exceptional case: normally we are not allowed to unhash a busy
+ * directory. In this case, however, we can do it - no aliasing problems
+ * due to the way we treat inodes.
+ *
+ * Rewrite the inode's ownerships here because the owning task may have
+ * performed a setuid(), etc.
+ *
+ * Before the /proc/pid/status file was created the only way to read
+ * the effective uid of a /process was to stat /proc/pid.  Reading
+ * /proc/pid/status is slow enough that procps and other packages
  * kept stating /proc/pid.  To keep the rules in /proc simple I have
  * made this apply to all per process world readable and executable
  * directories.
@@ -1348,25 +1038,130 @@ 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 *, 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, void *ptr)
+{
+       struct dentry *child, *dir = filp->f_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;
+}
+
+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);
 
-       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) {
+                       *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);
        }
-       rcu_read_unlock();
-       return 0;
+       return -ENOENT;
 }
 
 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
@@ -1404,75 +1199,30 @@ 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, 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 = *(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;
 
        /*
@@ -1482,13 +1232,14 @@ 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;
@@ -1496,137 +1247,153 @@ 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:
+ out:
+       return error;
+out_unlock:
        spin_unlock(&files->file_lock);
        put_files_struct(files);
-out_unlock:
+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 file_operations proc_fd_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_readfd,
-};
-
-static struct file_operations proc_task_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_task_readdir,
-};
-
-/*
- * proc directories can do almost nothing..
- */
-static struct inode_operations proc_fd_inode_operations = {
-       .lookup         = proc_lookupfd,
-};
-
-static struct inode_operations proc_task_inode_operations = {
-       .lookup         = proc_task_lookup,
-       .getattr        = proc_task_getattr,
-};
-
-#ifdef CONFIG_SECURITY
-static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
-                                 size_t count, loff_t *ppos)
+static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
 {
-       struct inode * inode = file->f_dentry->d_inode;
-       unsigned long page;
-       ssize_t length;
-       struct task_struct *task = get_proc_task(inode);
+       struct task_struct *task = get_proc_task(dir);
+       unsigned fd = name_to_int(dentry);
+       struct dentry *result = ERR_PTR(-ENOENT);
 
-       length = -ESRCH;
        if (!task)
                goto out_no_task;
-
-       if (count > PAGE_SIZE)
-               count = PAGE_SIZE;
-       length = -ENOMEM;
-       if (!(page = __get_free_page(GFP_KERNEL)))
+       if (fd == ~0U)
                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);
+       result = proc_fd_instantiate(dir, dentry, task, &fd);
 out:
        put_task_struct(task);
 out_no_task:
-       return length;
+       return result;
 }
 
-static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
-                                  size_t count, loff_t *ppos)
-{ 
-       struct inode * inode = file->f_dentry->d_inode;
-       char *page; 
-       ssize_t length; 
-       struct task_struct *task = get_proc_task(inode);
+static int proc_fd_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
+       struct task_struct *task, int fd)
+{
+       char name[PROC_NUMBUF];
+       int len = snprintf(name, sizeof(name), "%d", fd);
+       return proc_fill_cache(filp, dirent, filldir, name, len,
+                               proc_fd_instantiate, task, &fd);
+}
 
-       length = -ESRCH;
-       if (!task)
+static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
+{
+       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;
+       struct files_struct * files;
+       struct fdtable *fdt;
+
+       retval = -ENOENT;
+       if (!p)
                goto out_no_task;
-       if (count > PAGE_SIZE) 
-               count = PAGE_SIZE; 
+       retval = 0;
+       tid = p->pid;
 
-       /* No partial writes. */
-       length = -EINVAL;
-       if (*ppos != 0)
-               goto out;
-
-       length = -ENOMEM;
-       page = (char*)__get_free_page(GFP_USER); 
-       if (!page) 
-               goto out;
+       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++) {
 
-       length = -EFAULT; 
-       if (copy_from_user(page, buf, count)) 
-               goto out_free;
+                               if (!fcheck_files(files, fd))
+                                       continue;
+                               rcu_read_unlock();
 
-       length = security_setprocattr(task, 
-                                     (char*)file->f_dentry->d_name.name, 
-                                     (void*)page, count);
-out_free:
-       free_page((unsigned long) page);
+                               if (proc_fd_fill_cache(filp, dirent, filldir, p, fd) < 0) {
+                                       rcu_read_lock();
+                                       break;
+                               }
+                               rcu_read_lock();
+                       }
+                       rcu_read_unlock();
+                       put_files_struct(files);
+       }
 out:
-       put_task_struct(task);
+       put_task_struct(p);
 out_no_task:
-       return length;
-} 
+       return retval;
+}
 
-static struct file_operations proc_pid_attr_operations = {
-       .read           = proc_pid_attr_read,
-       .write          = proc_pid_attr_write,
+static struct file_operations proc_fd_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_readfd,
 };
 
-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
+/*
+ * proc directories can do almost nothing..
+ */
+static struct inode_operations proc_fd_inode_operations = {
+       .lookup         = proc_lookupfd,
+       .setattr        = proc_setattr,
+};
+
+static struct dentry *proc_pident_instantiate(struct inode *dir,
+       struct dentry *dentry, struct task_struct *task, void *ptr)
+{
+       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;
+}
 
-/* SMP-safe */
 static struct dentry *proc_pident_lookup(struct inode *dir, 
                                         struct dentry *dentry,
-                                        struct pid_entry *ents)
+                                        struct pid_entry *ents,
+                                        unsigned int nents)
 {
        struct inode *inode;
        struct dentry *error;
        struct task_struct *task = get_proc_task(dir);
-       struct pid_entry *p;
-       struct proc_inode *ei;
+       struct pid_entry *p, *last;
 
        error = ERR_PTR(-ENOENT);
        inode = NULL;
@@ -1634,295 +1401,416 @@ static struct dentry *proc_pident_lookup(struct inode *dir,
        if (!task)
                goto out_no_task;
 
-       for (p = ents; p->name; p++) {
+       /*
+        * 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->name)
+       if (p > last)
                goto out;
 
-       error = ERR_PTR(-EINVAL);
-       inode = proc_pid_make_inode(dir->i_sb, task, p->type);
-       if (!inode)
-               goto out;
+       error = proc_pident_instantiate(dir, dentry, task, p);
+out:
+       put_task_struct(task);
+out_no_task:
+       return error;
+}
 
-       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);
+static int proc_pident_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
+       struct task_struct *task, 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,
+               struct pid_entry *ents, unsigned int nents)
+{
+       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, *last;
+       ino_t ino;
+       int ret;
+
+       ret = -ENOENT;
+       if (!task)
+               goto out_no_task;
+
+       ret = 0;
+       pid = task->pid;
+       i = filp->f_pos;
+       switch (i) {
+       case 0:
+               ino = inode->i_ino;
+               if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
+                       goto out;
+               i++;
+               filp->f_pos++;
+               /* fall through */
+       case 1:
+               ino = parent_ino(dentry);
+               if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
+                       goto out;
+               i++;
+               filp->f_pos++;
+               /* fall through */
+       default:
+               i -= 2;
+               if (i >= nents) {
+                       ret = 1;
                        goto out;
+               }
+               p = ents + i;
+               last = &ents[nents - 1];
+               while (p <= last) {
+                       if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
+                               goto out;
+                       filp->f_pos++;
+                       p++;
+               }
        }
-       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;
+
+       ret = 1;
 out:
        put_task_struct(task);
 out_no_task:
-       return error;
+       return ret;
 }
 
-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);
+#ifdef CONFIG_SECURITY
+static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
+                                 size_t count, loff_t *ppos)
+{
+       struct inode * inode = file->f_dentry->d_inode;
+       unsigned long page;
+       ssize_t length;
+       struct task_struct *task = get_proc_task(inode);
+
+       length = -ESRCH;
+       if (!task)
+               goto out_no_task;
+
+       if (count > PAGE_SIZE)
+               count = PAGE_SIZE;
+       length = -ENOMEM;
+       if (!(page = __get_free_page(GFP_KERNEL)))
+               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);
+out:
+       put_task_struct(task);
+out_no_task:
+       return length;
 }
 
-static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
-       return proc_pident_lookup(dir, dentry, tid_base_stuff);
+static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
+                                  size_t count, loff_t *ppos)
+{
+       struct inode * inode = file->f_dentry->d_inode;
+       char *page;
+       ssize_t length;
+       struct task_struct *task = get_proc_task(inode);
+
+       length = -ESRCH;
+       if (!task)
+               goto out_no_task;
+       if (count > PAGE_SIZE)
+               count = PAGE_SIZE;
+
+       /* No partial writes. */
+       length = -EINVAL;
+       if (*ppos != 0)
+               goto out;
+
+       length = -ENOMEM;
+       page = (char*)__get_free_page(GFP_USER);
+       if (!page)
+               goto out;
+
+       length = -EFAULT;
+       if (copy_from_user(page, buf, count))
+               goto out_free;
+
+       length = security_setprocattr(task,
+                                     (char*)file->f_dentry->d_name.name,
+                                     (void*)page, count);
+out_free:
+       free_page((unsigned long) page);
+out:
+       put_task_struct(task);
+out_no_task:
+       return length;
 }
 
-static struct file_operations proc_tgid_base_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tgid_base_readdir,
+static struct file_operations proc_pid_attr_operations = {
+       .read           = proc_pid_attr_read,
+       .write          = proc_pid_attr_write,
 };
 
-static struct file_operations proc_tid_base_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tid_base_readdir,
+static 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),
 };
 
-static struct inode_operations proc_tgid_base_inode_operations = {
-       .lookup         = proc_tgid_base_lookup,
-       .getattr        = pid_getattr,
+static int proc_attr_dir_readdir(struct file * filp,
+                            void * dirent, filldir_t filldir)
+{
+       return proc_pident_readdir(filp,dirent,filldir,
+                                  attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
+}
+
+static struct file_operations proc_attr_dir_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_attr_dir_readdir,
 };
 
-static struct inode_operations proc_tid_base_inode_operations = {
-       .lookup         = proc_tid_base_lookup,
+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_attr_dir_inode_operations = {
+       .lookup         = proc_attr_dir_lookup,
        .getattr        = pid_getattr,
+       .setattr        = proc_setattr,
 };
 
-#ifdef CONFIG_SECURITY
-static int proc_tgid_attr_readdir(struct file * filp,
-                            void * dirent, filldir_t filldir)
+#endif
+
+/*
+ * /proc/self:
+ */
+static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
+                             int buflen)
 {
-       return proc_pident_readdir(filp,dirent,filldir,
-                                  tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff));
+       char tmp[PROC_NUMBUF];
+       sprintf(tmp, "%d", current->tgid);
+       return vfs_readlink(dentry,buffer,buflen,tmp);
 }
 
-static int proc_tid_attr_readdir(struct file * filp,
-                            void * dirent, filldir_t filldir)
+static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
-       return proc_pident_readdir(filp,dirent,filldir,
-                                  tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff));
+       char tmp[PROC_NUMBUF];
+       sprintf(tmp, "%d", current->tgid);
+       return ERR_PTR(vfs_follow_link(nd,tmp));
 }
 
-static struct file_operations proc_tgid_attr_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tgid_attr_readdir,
+static struct inode_operations proc_self_inode_operations = {
+       .readlink       = proc_self_readlink,
+       .follow_link    = proc_self_follow_link,
 };
 
-static struct file_operations proc_tid_attr_operations = {
-       .read           = generic_read_dir,
-       .readdir        = proc_tid_attr_readdir,
+/*
+ * proc base
+ *
+ * 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.
+ */
+static struct pid_entry proc_base_stuff[] = {
+       NOD("self", S_IFLNK|S_IRWXUGO,
+               &proc_self_inode_operations, NULL, {}),
 };
 
-static struct dentry *proc_tgid_attr_lookup(struct inode *dir,
-                               struct dentry *dentry, struct nameidata *nd)
+/*
+ *     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)
 {
-       return proc_pident_lookup(dir, dentry, tgid_attr_stuff);
+       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 *proc_tid_attr_lookup(struct inode *dir,
-                               struct dentry *dentry, struct nameidata *nd)
+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, void *ptr)
+{
+       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);
+       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, struct pid_entry *p)
+{
+       return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
+                               proc_base_instantiate, task, p);
+}
+
+/*
+ * Thread groups
+ */
+static struct file_operations proc_task_operations;
+static struct inode_operations proc_task_inode_operations;
+
+static struct pid_entry tgid_base_stuff[] = {
+       DIR("task",       S_IRUGO|S_IXUGO, task),
+       DIR("fd",         S_IRUSR|S_IXUSR, fd),
+       INF("environ",    S_IRUSR, pid_environ),
+       INF("auxv",       S_IRUSR, pid_auxv),
+       INF("status",     S_IRUGO, pid_status),
+       INF("cmdline",    S_IRUGO, pid_cmdline),
+       INF("stat",       S_IRUGO, tgid_stat),
+       INF("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),
+#ifdef CONFIG_SECCOMP
+       REG("seccomp",    S_IRUSR|S_IWUSR, seccomp),
+#endif
+       LNK("cwd",        cwd),
+       LNK("root",       root),
+       LNK("exe",        exe),
+       REG("mounts",     S_IRUGO, mounts),
+       REG("mountstats", S_IRUSR, mountstats),
+#ifdef CONFIG_MMU
+       REG("smaps",      S_IRUGO, smaps),
+#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_CPUSETS
+       REG("cpuset",     S_IRUGO, cpuset),
+#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
+};
+
+static int proc_tgid_base_readdir(struct file * filp,
+                            void * dirent, filldir_t filldir)
 {
-       return proc_pident_lookup(dir, dentry, tid_attr_stuff);
+       return proc_pident_readdir(filp,dirent,filldir,
+                                  tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
 }
 
-static struct inode_operations proc_tgid_attr_inode_operations = {
-       .lookup         = proc_tgid_attr_lookup,
-       .getattr        = pid_getattr,
-};
-
-static struct inode_operations proc_tid_attr_inode_operations = {
-       .lookup         = proc_tid_attr_lookup,
-       .getattr        = pid_getattr,
+static struct file_operations proc_tgid_base_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_tgid_base_readdir,
 };
-#endif
 
-/*
- * /proc/self:
- */
-static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
-                             int buflen)
-{
-       char tmp[PROC_NUMBUF];
-       sprintf(tmp, "%d", current->tgid);
-       return vfs_readlink(dentry,buffer,buflen,tmp);
+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 void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
-{
-       char tmp[PROC_NUMBUF];
-       sprintf(tmp, "%d", current->tgid);
-       return ERR_PTR(vfs_follow_link(nd,tmp));
-}      
-
-static struct inode_operations proc_self_inode_operations = {
-       .readlink       = proc_self_readlink,
-       .follow_link    = proc_self_follow_link,
+static struct inode_operations proc_tgid_base_inode_operations = {
+       .lookup         = proc_tgid_base_lookup,
+       .getattr        = pid_getattr,
+       .setattr        = proc_setattr,
 };
 
 /**
@@ -1992,54 +1880,23 @@ out:
        return;
 }
 
-/* SMP-safe */
-struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
+struct dentry *proc_pid_instantiate(struct inode *dir,
+       struct dentry * dentry, struct task_struct *task, void *ptr)
 {
-       struct dentry *result = ERR_PTR(-ENOENT);
-       struct task_struct *task;
+       struct dentry *error = ERR_PTR(-ENOENT);
        struct inode *inode;
-       struct proc_inode *ei;
-       unsigned tgid;
-
-       if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) {
-               inode = new_inode(dir->i_sb);
-               if (!inode)
-                       return ERR_PTR(-ENOMEM);
-               ei = PROC_I(inode);
-               inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
-               inode->i_ino = fake_ino(0, PROC_TGID_INO);
-               ei->pde = NULL;
-               inode->i_mode = S_IFLNK|S_IRWXUGO;
-               inode->i_uid = inode->i_gid = 0;
-               inode->i_size = 64;
-               inode->i_op = &proc_self_inode_operations;
-               d_add(dentry, inode);
-               return NULL;
-       }
-       tgid = name_to_int(dentry);
-       if (tgid == ~0U)
-               goto out;
-
-       rcu_read_lock();
-       task = find_task_by_pid(tgid);
-       if (task)
-               get_task_struct(task);
-       rcu_read_unlock();
-       if (!task)
-               goto out;
 
-       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;
@@ -2047,178 +1904,250 @@ 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;
 
-       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;
 
        rcu_read_lock();
-       task = find_task_by_pid(tid);
+       task = find_task_by_pid(tgid);
        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.
+ * Find the first task with tgid >= tgid
  *
- * In the case of a short read we start with find_task_by_pid.
- *
- * 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)
+static struct task_struct *next_tgid(unsigned int tgid)
 {
-       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 task_struct *task;
+       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;
-               }
+       rcu_read_lock();
+retry:
+       task = NULL;
+       pid = find_ge_pid(tgid);
+       if (pid) {
+               tgid = pid->nr + 1;
+               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 (!task || !has_group_leader_pid(task))
+                       goto retry;
+               get_task_struct(task);
        }
-found:
-       get_task_struct(pos);
-done:
        rcu_read_unlock();
-       return pos;
+       return task;
 }
 
-/*
- * 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 task_struct *task, int tgid)
 {
-       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", tgid);
+       return proc_fill_cache(filp, dirent, filldir, name, len,
+                               proc_pid_instantiate, 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 *reaper = get_proc_task(filp->f_dentry->d_inode);
        struct task_struct *task;
        int tgid;
 
-       if (!nr) {
-               ino_t ino = fake_ino(0,PROC_TGID_INO);
-               if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0)
-                       return 0;
-               filp->f_pos++;
-               nr++;
+       if (!reaper)
+               goto out_no_task;
+
+       for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
+               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);
+       tgid = filp->f_pos - TGID_OFFSET;
+       for (task = next_tgid(tgid);
             task;
-            task = next_tgid(task), filp->f_pos++) {
-               int len;
-               ino_t ino;
+            put_task_struct(task), task = next_tgid(tgid + 1)) {
                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;
+               filp->f_pos = tgid + TGID_OFFSET;
+               if (proc_pid_fill_cache(filp, dirent, filldir, task, tgid) < 0) {
                        put_task_struct(task);
-                       break;
+                       goto out;
                }
        }
+       filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
+out:
+       put_task_struct(reaper);
+out_no_task:
        return 0;
 }
 
+/*
+ * Tasks
+ */
+static struct pid_entry tid_base_stuff[] = {
+       DIR("fd",        S_IRUSR|S_IXUSR, fd),
+       INF("environ",   S_IRUSR, pid_environ),
+       INF("auxv",      S_IRUSR, pid_auxv),
+       INF("status",    S_IRUGO, pid_status),
+       INF("cmdline",   S_IRUGO, pid_cmdline),
+       INF("stat",      S_IRUGO, tid_stat),
+       INF("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),
+#ifdef CONFIG_SECCOMP
+       REG("seccomp",   S_IRUSR|S_IWUSR, seccomp),
+#endif
+       LNK("cwd",       cwd),
+       LNK("root",      root),
+       LNK("exe",       exe),
+       REG("mounts",    S_IRUGO, mounts),
+#ifdef CONFIG_MMU
+       REG("smaps",     S_IRUGO, smaps),
+#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_CPUSETS
+       REG("cpuset",    S_IRUGO, cpuset),
+#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
+};
+
+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 struct file_operations proc_tid_base_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_tid_base_readdir,
+};
+
+static 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, 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 = 3;
+#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;
+
+       if (!leader)
+               goto out_no_task;
+
+       tid = name_to_int(dentry);
+       if (tid == ~0U)
+               goto out;
+
+       rcu_read_lock();
+       task = find_task_by_pid(tid);
+       if (task)
+               get_task_struct(task);
+       rcu_read_unlock();
+       if (!task)
+               goto out;
+       if (leader->tgid != task->tgid)
+               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.
  *
@@ -2288,10 +2217,18 @@ 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 inode *inode = dentry->d_inode;
        struct task_struct *leader = get_proc_task(inode);
@@ -2328,11 +2265,8 @@ static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldi
        for (task = first_tid(leader, tid, pos - 2);
             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)) {
+               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;
@@ -2362,3 +2296,14 @@ static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct
 
        return 0;
 }
+
+static struct inode_operations proc_task_inode_operations = {
+       .lookup         = proc_task_lookup,
+       .getattr        = proc_task_getattr,
+       .setattr        = proc_setattr,
+};
+
+static struct file_operations proc_task_operations = {
+       .read           = generic_read_dir,
+       .readdir        = proc_task_readdir,
+};