Merge branch 'akpm' (Andrew's incoming - part two)

Says Andrew:

 "60 patches.  That's good enough for -rc1 I guess.  I have quite a lot
  of detritus to be rechecked, work through maintainers, etc.

 - most of the remains of MM
 - rtc
 - various misc
 - cgroups
 - memcg
 - cpusets
 - procfs
 - ipc
 - rapidio
 - sysctl
 - pps
 - w1
 - drivers/misc
 - aio"

* akpm: (60 commits)
  memcg: replace ss->id_lock with a rwlock
  aio: allocate kiocbs in batches
  drivers/misc/vmw_balloon.c: fix typo in code comment
  drivers/misc/vmw_balloon.c: determine page allocation flag can_sleep outside loop
  w1: disable irqs in critical section
  drivers/w1/w1_int.c: multiple masters used same init_name
  drivers/power/ds2780_battery.c: fix deadlock upon insertion and removal
  drivers/power/ds2780_battery.c: add a nolock function to w1 interface
  drivers/power/ds2780_battery.c: create central point for calling w1 interface
  w1: ds2760 and ds2780, use ida for id and ida_simple_get() to get it
  pps gpio client: add missing dependency
  pps: new client driver using GPIO
  pps: default echo function
  include/linux/dma-mapping.h: add dma_zalloc_coherent()
  sysctl: make CONFIG_SYSCTL_SYSCALL default to n
  sysctl: add support for poll()
  RapidIO: documentation update
  drivers/net/rionet.c: fix ethernet address macros for LE platforms
  RapidIO: fix potential null deref in rio_setup_device()
  RapidIO: add mport driver for Tsi721 bridge
  ...

2 files changed, 149 insertions, 43 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 851ba3d..2db1bd3 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1652,12 +1652,46 @@ out:
 	return error;
 }
 
+static int proc_pid_fd_link_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	struct task_struct *task = get_proc_task(inode);
+	int rc;
+
+	if (task == NULL)
+		return -ESRCH;
+
+	rc = -EACCES;
+	if (lock_trace(task))
+		goto out_task;
+
+	generic_fillattr(inode, stat);
+	unlock_trace(task);
+	rc = 0;
+out_task:
+	put_task_struct(task);
+	return rc;
+}
+
 static const struct inode_operations proc_pid_link_inode_operations = {
 	.readlink	= proc_pid_readlink,
 	.follow_link	= proc_pid_follow_link,
 	.setattr	= proc_setattr,
 };
 
+static const struct inode_operations proc_fdinfo_link_inode_operations = {
+	.setattr	= proc_setattr,
+	.getattr	= proc_pid_fd_link_getattr,
+};
+
+static const struct inode_operations proc_fd_link_inode_operations = {
+	.readlink	= proc_pid_readlink,
+	.follow_link	= proc_pid_follow_link,
+	.setattr	= proc_setattr,
+	.getattr	= proc_pid_fd_link_getattr,
+};
+
 
 /* building an inode */
 
@@ -1889,49 +1923,61 @@ out:
 
 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 task_struct *task;
+	struct files_struct *files;
 	struct file *file;
 	int fd = proc_fd(inode);
+	int rc;
 
-	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) {
-			unsigned int f_flags;
-			struct fdtable *fdt;
-
-			fdt = files_fdtable(files);
-			f_flags = file->f_flags & ~O_CLOEXEC;
-			if (FD_ISSET(fd, fdt->close_on_exec))
-				f_flags |= O_CLOEXEC;
-
-			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,
-					 f_flags);
-			spin_unlock(&files->file_lock);
-			put_files_struct(files);
-			return 0;
+	task = get_proc_task(inode);
+	if (!task)
+		return -ENOENT;
+
+	rc = -EACCES;
+	if (lock_trace(task))
+		goto out_task;
+
+	rc = -ENOENT;
+	files = get_files_struct(task);
+	if (files == NULL)
+		goto out_unlock;
+
+	/*
+	 * 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) {
+		unsigned int f_flags;
+		struct fdtable *fdt;
+
+		fdt = files_fdtable(files);
+		f_flags = file->f_flags & ~O_CLOEXEC;
+		if (FD_ISSET(fd, fdt->close_on_exec))
+			f_flags |= O_CLOEXEC;
+
+		if (path) {
+			*path = file->f_path;
+			path_get(&file->f_path);
 		}
-		spin_unlock(&files->file_lock);
-		put_files_struct(files);
-	}
-	return -ENOENT;
+		if (info)
+			snprintf(info, PROC_FDINFO_MAX,
+				 "pos:\t%lli\n"
+				 "flags:\t0%o\n",
+				 (long long) file->f_pos,
+				 f_flags);
+		rc = 0;
+	} else
+		rc = -ENOENT;
+	spin_unlock(&files->file_lock);
+	put_files_struct(files);
+
+out_unlock:
+	unlock_trace(task);
+out_task:
+	put_task_struct(task);
+	return rc;
 }
 
 static int proc_fd_link(struct inode *inode, struct path *path)
@@ -2026,7 +2072,7 @@ static struct dentry *proc_fd_instantiate(struct inode *dir,
 	spin_unlock(&files->file_lock);
 	put_files_struct(files);
 
-	inode->i_op = &proc_pid_link_inode_operations;
+	inode->i_op = &proc_fd_link_inode_operations;
 	inode->i_size = 64;
 	ei->op.proc_get_link = proc_fd_link;
 	d_set_d_op(dentry, &tid_fd_dentry_operations);
@@ -2058,7 +2104,12 @@ static struct dentry *proc_lookupfd_common(struct inode *dir,
 	if (fd == ~0U)
 		goto out;
 
+	result = ERR_PTR(-EACCES);
+	if (lock_trace(task))
+		goto out;
+
 	result = instantiate(dir, dentry, task, &fd);
+	unlock_trace(task);
 out:
 	put_task_struct(task);
 out_no_task:
@@ -2078,23 +2129,28 @@ static int proc_readfd_common(struct file * filp, void * dirent,
 	retval = -ENOENT;
 	if (!p)
 		goto out_no_task;
+
+	retval = -EACCES;
+	if (lock_trace(p))
+		goto out;
+
 	retval = 0;
 
 	fd = filp->f_pos;
 	switch (fd) {
 		case 0:
 			if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
-				goto out;
+				goto out_unlock;
 			filp->f_pos++;
 		case 1:
 			ino = parent_ino(dentry);
 			if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
-				goto out;
+				goto out_unlock;
 			filp->f_pos++;
 		default:
 			files = get_files_struct(p);
 			if (!files)
-				goto out;
+				goto out_unlock;
 			rcu_read_lock();
 			for (fd = filp->f_pos-2;
 			     fd < files_fdtable(files)->max_fds;
@@ -2118,6 +2174,9 @@ static int proc_readfd_common(struct file * filp, void * dirent,
 			rcu_read_unlock();
 			put_files_struct(files);
 	}
+
+out_unlock:
+	unlock_trace(p);
 out:
 	put_task_struct(p);
 out_no_task:
@@ -2195,6 +2254,7 @@ static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
 	ei->fd = fd;
 	inode->i_mode = S_IFREG | S_IRUSR;
 	inode->i_fop = &proc_fdinfo_file_operations;
+	inode->i_op = &proc_fdinfo_link_inode_operations;
 	d_set_d_op(dentry, &tid_fd_dentry_operations);
 	d_add(dentry, inode);
 	/* Close the race of the process dying before we return the dentry */
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index b441132..a6b6217 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -3,6 +3,7 @@
  */
 #include <linux/init.h>
 #include <linux/sysctl.h>
+#include <linux/poll.h>
 #include <linux/proc_fs.h>
 #include <linux/security.h>
 #include <linux/namei.h>
@@ -14,6 +15,15 @@ static const struct inode_operations proc_sys_inode_operations;
 static const struct file_operations proc_sys_dir_file_operations;
 static const struct inode_operations proc_sys_dir_operations;
 
+void proc_sys_poll_notify(struct ctl_table_poll *poll)
+{
+	if (!poll)
+		return;
+
+	atomic_inc(&poll->event);
+	wake_up_interruptible(&poll->wait);
+}
+
 static struct inode *proc_sys_make_inode(struct super_block *sb,
 		struct ctl_table_header *head, struct ctl_table *table)
 {
@@ -176,6 +186,39 @@ static ssize_t proc_sys_write(struct file *filp, const char __user *buf,
 	return proc_sys_call_handler(filp, (void __user *)buf, count, ppos, 1);
 }
 
+static int proc_sys_open(struct inode *inode, struct file *filp)
+{
+	struct ctl_table *table = PROC_I(inode)->sysctl_entry;
+
+	if (table->poll)
+		filp->private_data = proc_sys_poll_event(table->poll);
+
+	return 0;
+}
+
+static unsigned int proc_sys_poll(struct file *filp, poll_table *wait)
+{
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct ctl_table *table = PROC_I(inode)->sysctl_entry;
+	unsigned long event = (unsigned long)filp->private_data;
+	unsigned int ret = DEFAULT_POLLMASK;
+
+	if (!table->proc_handler)
+		goto out;
+
+	if (!table->poll)
+		goto out;
+
+	poll_wait(filp, &table->poll->wait, wait);
+
+	if (event != atomic_read(&table->poll->event)) {
+		filp->private_data = proc_sys_poll_event(table->poll);
+		ret = POLLIN | POLLRDNORM | POLLERR | POLLPRI;
+	}
+
+out:
+	return ret;
+}
 
 static int proc_sys_fill_cache(struct file *filp, void *dirent,
 				filldir_t filldir,
@@ -364,12 +407,15 @@ static int proc_sys_getattr(struct vfsmount *mnt, struct dentry *dentry, struct
 }
 
 static const struct file_operations proc_sys_file_operations = {
+	.open		= proc_sys_open,
+	.poll		= proc_sys_poll,
 	.read		= proc_sys_read,
 	.write		= proc_sys_write,
 	.llseek		= default_llseek,
 };
 
 static const struct file_operations proc_sys_dir_file_operations = {
+	.read		= generic_read_dir,
 	.readdir	= proc_sys_readdir,
 	.llseek		= generic_file_llseek,
 };