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 851ba3dcdc29..2db1bd3173b2 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 b44113279e30..a6b62173d4c3 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,
 };