[PATCH] proc: Use struct pid not struct task_ref

Incrementally update my proc-dont-lock-task_structs-indefinitely patches so
that they work with struct pid instead of struct task_ref.

Mostly this is a straight 1-1 substitution.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/proc/base.c

@@ -951,7 +951,7 @@ static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
 	if (!capable(CAP_AUDIT_CONTROL))
 		return -EPERM;
 
-	if (current != proc_tref(inode)->task)
+	if (current != pid_task(proc_pid(inode), PIDTYPE_PID))
 		return -EPERM;
 
 	if (count >= PAGE_SIZE)
@@ -1363,8 +1363,8 @@ static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_st
 	/*
 	 * grab the reference to task.
 	 */
-	ei->tref = tref_get_by_task(task);
-	if (!tref_task(ei->tref))
+	ei->pid = get_pid(task->pids[PIDTYPE_PID].pid);
+	if (!ei->pid)
 		goto out_unlock;
 
 	inode->i_uid = 0;
@@ -1482,7 +1482,7 @@ static int pid_delete_dentry(struct dentry * dentry)
 	 * If so, then don't put the dentry on the lru list,
 	 * kill it immediately.
 	 */
-	return !proc_tref(dentry->d_inode)->task;
+	return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
 }
 
 static struct dentry_operations tid_fd_dentry_operations =

fs/proc/inode.c

@@ -62,7 +62,7 @@ static void proc_delete_inode(struct inode *inode)
 	truncate_inode_pages(&inode->i_data, 0);
 
 	/* Stop tracking associated processes */
-	tref_put(PROC_I(inode)->tref);
+	put_pid(PROC_I(inode)->pid);
 
 	/* Let go of any associated proc directory entry */
 	de = PROC_I(inode)->pde;
@@ -91,7 +91,7 @@ static struct inode *proc_alloc_inode(struct super_block *sb)
 	ei = (struct proc_inode *)kmem_cache_alloc(proc_inode_cachep, SLAB_KERNEL);
 	if (!ei)
 		return NULL;
-	ei->tref = NULL;
+	ei->pid = NULL;
 	ei->fd = 0;
 	ei->op.proc_get_link = NULL;
 	ei->pde = NULL;

fs/proc/internal.h

@@ -10,7 +10,6 @@
  */
 
 #include <linux/proc_fs.h>
-#include <linux/task_ref.h>
 
 struct vmalloc_info {
 	unsigned long	used;
@@ -51,14 +50,14 @@ void free_proc_entry(struct proc_dir_entry *de);
 
 int proc_init_inodecache(void);
 
-static inline struct task_ref *proc_tref(struct inode *inode)
+static inline struct pid *proc_pid(struct inode *inode)
 {
-	return PROC_I(inode)->tref;
+	return PROC_I(inode)->pid;
 }
 
 static inline struct task_struct *get_proc_task(struct inode *inode)
 {
-	return get_tref_task(proc_tref(inode));
+	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
 }
 
 static inline int proc_fd(struct inode *inode)

fs/proc/task_mmu.c

@@ -320,7 +320,7 @@ static void *m_start(struct seq_file *m, loff_t *pos)
 	if (last_addr == -1UL)
 		return NULL;
 
-	priv->task = get_tref_task(priv->tref);
+	priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
 	if (!priv->task)
 		return NULL;
 
@@ -416,7 +416,7 @@ static int do_maps_open(struct inode *inode, struct file *file,
 	int ret = -ENOMEM;
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (priv) {
-		priv->tref = proc_tref(inode);
+		priv->pid = proc_pid(inode);
 		ret = seq_open(file, ops);
 		if (!ret) {
 			struct seq_file *m = file->private_data;

include/linux/proc_fs.h

@@ -246,7 +246,7 @@ extern void kclist_add(struct kcore_list *, void *, size_t);
 #endif
 
 struct proc_inode {
-	struct task_ref *tref;
+	struct pid *pid;
 	int fd;
 	union {
 		int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
@@ -267,7 +267,7 @@ static inline struct proc_dir_entry *PDE(const struct inode *inode)
 }
 
 struct proc_maps_private {
-	struct task_ref *tref;
+	struct pid *pid;
 	struct task_struct *task;
 	struct vm_area_struct *tail_vma;
 };

kernel/cpuset.c

@@ -50,7 +50,6 @@
 #include <linux/time.h>
 #include <linux/backing-dev.h>
 #include <linux/sort.h>
-#include <linux/task_ref.h>
 
 #include <asm/uaccess.h>
 #include <asm/atomic.h>
@@ -2443,7 +2442,7 @@ void __cpuset_memory_pressure_bump(void)
  */
 static int proc_cpuset_show(struct seq_file *m, void *v)
 {
-	struct task_ref *tref;
+	struct pid *pid;
 	struct task_struct *tsk;
 	char *buf;
 	int retval;
@@ -2454,8 +2453,8 @@ static int proc_cpuset_show(struct seq_file *m, void *v)
 		goto out;
 
 	retval = -ESRCH;
-	tref = m->private;
-	tsk = get_tref_task(tref);
+	pid = m->private;
+	tsk = get_pid_task(pid, PIDTYPE_PID);
 	if (!tsk)
 		goto out_free;
 
@@ -2478,8 +2477,8 @@ out:
 
 static int cpuset_open(struct inode *inode, struct file *file)
 {
-	struct task_ref *tref = PROC_I(inode)->tref;
-	return single_open(file, proc_cpuset_show, tref);
+	struct pid *pid = PROC_I(inode)->pid;
+	return single_open(file, proc_cpuset_show, pid);
 }
 
 struct file_operations proc_cpuset_operations = {