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

Pull vfs updates from Al Viro:
 "Stuff in here:

   - acct.c fixes and general rework of mnt_pin mechanism.  That allows
     to go for delayed-mntput stuff, which will permit mntput() on deep
     stack without worrying about stack overflows - fs shutdown will
     happen on shallow stack.  IOW, we can do Eric's umount-on-rmdir
     series without introducing tons of stack overflows on new mntput()
     call chains it introduces.
   - Bruce's d_splice_alias() patches
   - more Miklos' rename() stuff.
   - a couple of regression fixes (stable fodder, in the end of branch)
     and a fix for API idiocy in iov_iter.c.

  There definitely will be another pile, maybe even two.  I'd like to
  get Eric's series in this time, but even if we miss it, it'll go right
  in the beginning of for-next in the next cycle - the tricky part of
  prereqs is in this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  fix copy_tree() regression
  __generic_file_write_iter(): fix handling of sync error after DIO
  switch iov_iter_get_pages() to passing maximal number of pages
  fs: mark __d_obtain_alias static
  dcache: d_splice_alias should detect loops
  exportfs: update Exporting documentation
  dcache: d_find_alias needn't recheck IS_ROOT && DCACHE_DISCONNECTED
  dcache: remove unused d_find_alias parameter
  dcache: d_obtain_alias callers don't all want DISCONNECTED
  dcache: d_splice_alias should ignore DCACHE_DISCONNECTED
  dcache: d_splice_alias mustn't create directory aliases
  dcache: close d_move race in d_splice_alias
  dcache: move d_splice_alias
  namei: trivial fix to vfs_rename_dir comment
  VFS: allow ->d_manage() to declare -EISDIR in rcu_walk mode.
  cifs: support RENAME_NOREPLACE
  hostfs: support rename flags
  shmem: support RENAME_EXCHANGE
  shmem: support RENAME_NOREPLACE
  btrfs: add RENAME_NOREPLACE
  ...

6 files changed, 23 insertions, 7 deletions

diff --git a/include/linux/acct.h b/include/linux/acct.h
index 4a5b7cb56079..dccc2d4fe7de 100644
--- a/include/linux/acct.h
+++ b/include/linux/acct.h
@@ -24,14 +24,10 @@ struct super_block;
 struct pacct_struct;
 struct pid_namespace;
 extern int acct_parm[]; /* for sysctl */
-extern void acct_auto_close_mnt(struct vfsmount *m);
-extern void acct_auto_close(struct super_block *sb);
 extern void acct_collect(long exitcode, int group_dead);
 extern void acct_process(void);
 extern void acct_exit_ns(struct pid_namespace *);
 #else
-#define acct_auto_close_mnt(x)  do { } while (0)
-#define acct_auto_close(x)      do { } while (0)
 #define acct_collect(x,y)       do { } while (0)
 #define acct_process()          do { } while (0)
 #define acct_exit_ns(ns)        do { } while (0)
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 3c7ec327ebd2..e4ae2ad48d07 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -249,6 +249,7 @@ extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
 extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
 extern struct dentry *d_find_any_alias(struct inode *inode);
 extern struct dentry * d_obtain_alias(struct inode *);
+extern struct dentry * d_obtain_root(struct inode *);
 extern void shrink_dcache_sb(struct super_block *);
 extern void shrink_dcache_parent(struct dentry *);
 extern void shrink_dcache_for_umount(struct super_block *);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f0890e4a7c25..94187721ad41 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1275,6 +1275,7 @@ struct super_block {
 
         /* AIO completions deferred from interrupt context */
         struct workqueue_struct *s_dio_done_wq;
+        struct hlist_head s_pins;
 
         /*
          * Keep the lru lists last in the structure so they always sit on their
@@ -2360,6 +2361,7 @@ extern int do_pipe_flags(int *, int);
 
 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
 extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
+extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
 extern struct file * open_exec(const char *);
  
 /* fs/dcache.c -- generic fs support functions */
diff --git a/include/linux/fs_pin.h b/include/linux/fs_pin.h
new file mode 100644
index 000000000000..f66525e72ccf
--- /dev/null
+++ b/include/linux/fs_pin.h
@@ -0,0 +1,17 @@
+#include <linux/fs.h>
+
+struct fs_pin {
+        atomic_long_t           count;
+        union {
+                struct {
+                        struct hlist_node       s_list;
+                        struct hlist_node       m_list;
+                };
+                struct rcu_head rcu;
+        };
+        void (*kill)(struct fs_pin *);
+};
+
+void pin_put(struct fs_pin *);
+void pin_remove(struct fs_pin *);
+void pin_insert(struct fs_pin *, struct vfsmount *);
diff --git a/include/linux/mount.h b/include/linux/mount.h
index b0c1e6574e7f..9262e4bf0cc3 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -69,6 +69,7 @@ struct vfsmount {
 };
 
 struct file; /* forward dec */
+struct path;
 
 extern int mnt_want_write(struct vfsmount *mnt);
 extern int mnt_want_write_file(struct file *file);
@@ -77,8 +78,7 @@ extern void mnt_drop_write(struct vfsmount *mnt);
 extern void mnt_drop_write_file(struct file *file);
 extern void mntput(struct vfsmount *mnt);
 extern struct vfsmount *mntget(struct vfsmount *mnt);
-extern void mnt_pin(struct vfsmount *mnt);
-extern void mnt_unpin(struct vfsmount *mnt);
+extern struct vfsmount *mnt_clone_internal(struct path *path);
 extern int __mnt_is_readonly(struct vfsmount *mnt);
 
 struct file_system_type;
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 09a7cffc224e..48d64e6ab292 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -84,7 +84,7 @@ unsigned long iov_iter_alignment(const struct iov_iter *i);
 void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov,
                         unsigned long nr_segs, size_t count);
 ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
-                        size_t maxsize, size_t *start);
+                        unsigned maxpages, size_t *start);
 ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,
                         size_t maxsize, size_t *start);
 int iov_iter_npages(const struct iov_iter *i, int maxpages);