Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs update from Al Viro:

 - big one - consolidation of descriptor-related logics; almost all of
   that is moved to fs/file.c

   (BTW, I'm seriously tempted to rename the result to fd.c.  As it is,
   we have a situation when file_table.c is about handling of struct
   file and file.c is about handling of descriptor tables; the reasons
   are historical - file_table.c used to be about a static array of
   struct file we used to have way back).

   A lot of stray ends got cleaned up and converted to saner primitives,
   disgusting mess in android/binder.c is still disgusting, but at least
   doesn't poke so much in descriptor table guts anymore.  A bunch of
   relatively minor races got fixed in process, plus an ext4 struct file
   leak.

 - related thing - fget_light() partially unuglified; see fdget() in
   there (and yes, it generates the code as good as we used to have).

 - also related - bits of Cyrill's procfs stuff that got entangled into
   that work; _not_ all of it, just the initial move to fs/proc/fd.c and
   switch of fdinfo to seq_file.

 - Alex's fs/coredump.c spiltoff - the same story, had been easier to
   take that commit than mess with conflicts.  The rest is a separate
   pile, this was just a mechanical code movement.

 - a few misc patches all over the place.  Not all for this cycle,
   there'll be more (and quite a few currently sit in akpm's tree)."

Fix up trivial conflicts in the android binder driver, and some fairly
simple conflicts due to two different changes to the sock_alloc_file()
interface ("take descriptor handling from sock_alloc_file() to callers"
vs "net: Providing protocol type via system.sockprotoname xattr of
/proc/PID/fd entries" adding a dentry name to the socket)

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits)
  MAX_LFS_FILESIZE should be a loff_t
  compat: fs: Generic compat_sys_sendfile implementation
  fs: push rcu_barrier() from deactivate_locked_super() to filesystems
  btrfs: reada_extent doesn't need kref for refcount
  coredump: move core dump functionality into its own file
  coredump: prevent double-free on an error path in core dumper
  usb/gadget: fix misannotations
  fcntl: fix misannotations
  ceph: don't abuse d_delete() on failure exits
  hypfs: ->d_parent is never NULL or negative
  vfs: delete surplus inode NULL check
  switch simple cases of fget_light to fdget
  new helpers: fdget()/fdput()
  switch o2hb_region_dev_write() to fget_light()
  proc_map_files_readdir(): don't bother with grabbing files
  make get_file() return its argument
  vhost_set_vring(): turn pollstart/pollstop into bool
  switch prctl_set_mm_exe_file() to fget_light()
  switch xfs_find_handle() to fget_light()
  switch xfs_swapext() to fget_light()
  ...

1 files changed, 16 insertions, 29 deletions

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 8a5a8b064616..2ea176b2280e 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1166,10 +1166,8 @@ ssize_t redirected_tty_write(struct file *file, const char __user *buf,
         struct file *p = NULL;
 
         spin_lock(&redirect_lock);
-        if (redirect) {
-                get_file(redirect);
-                p = redirect;
-        }
+        if (redirect)
+                p = get_file(redirect);
         spin_unlock(&redirect_lock);
 
         if (p) {
@@ -2264,8 +2262,7 @@ static int tioccons(struct file *file)
                 spin_unlock(&redirect_lock);
                 return -EBUSY;
         }
-        get_file(file);
-        redirect = file;
+        redirect = get_file(file);
         spin_unlock(&redirect_lock);
         return 0;
 }
@@ -2809,6 +2806,13 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
 }
 #endif
 
+static int this_tty(const void *t, struct file *file, unsigned fd)
+{
+        if (likely(file->f_op->read != tty_read))
+                return 0;
+        return file_tty(file) != t ? 0 : fd + 1;
+}
+        
 /*
  * This implements the "Secure Attention Key" ---  the idea is to
  * prevent trojan horses by killing all processes associated with this
@@ -2836,8 +2840,6 @@ void __do_SAK(struct tty_struct *tty)
         struct task_struct *g, *p;
         struct pid *session;
         int             i;
-        struct file     *filp;
-        struct fdtable *fdt;
 
         if (!tty)
                 return;
@@ -2867,27 +2869,12 @@ void __do_SAK(struct tty_struct *tty)
                         continue;
                 }
                 task_lock(p);
-                if (p->files) {
-                        /*
-                         * We don't take a ref to the file, so we must
-                         * hold ->file_lock instead.
-                         */
-                        spin_lock(&p->files->file_lock);
-                        fdt = files_fdtable(p->files);
-                        for (i = 0; i < fdt->max_fds; i++) {
-                                filp = fcheck_files(p->files, i);
-                                if (!filp)
-                                        continue;
-                                if (filp->f_op->read == tty_read &&
-                                    file_tty(filp) == tty) {
-                                        printk(KERN_NOTICE "SAK: killed process %d"
-                                            " (%s): fd#%d opened to the tty\n",
-                                            task_pid_nr(p), p->comm, i);
-                                        force_sig(SIGKILL, p);
-                                        break;
-                                }
-                        }
-                        spin_unlock(&p->files->file_lock);
+                i = iterate_fd(p->files, 0, this_tty, tty);
+                if (i != 0) {
+                        printk(KERN_NOTICE "SAK: killed process %d"
+                            " (%s): fd#%d opened to the tty\n",
+                                    task_pid_nr(p), p->comm, i - 1);
+                        force_sig(SIGKILL, p);
                 }
                 task_unlock(p);
         } while_each_thread(g, p);