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

Pull vfs changes from Al Viro.
 "A lot of misc stuff.  The obvious groups:
   * Miklos' atomic_open series; kills the damn abuse of
     ->d_revalidate() by NFS, which was the major stumbling block for
     all work in that area.
   * ripping security_file_mmap() and dealing with deadlocks in the
     area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in
     general.
   * ->encode_fh() switched to saner API; insane fake dentry in
     mm/cleancache.c gone.
   * assorted annotations in fs (endianness, __user)
   * parts of Artem's ->s_dirty work (jff2 and reiserfs parts)
   * ->update_time() work from Josef.
   * other bits and pieces all over the place.

  Normally it would've been in two or three pull requests, but
  signal.git stuff had eaten a lot of time during this cycle ;-/"

Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the
'truncate_range' inode method was removed by the VM changes, the VFS
update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due
to sparse fix added twice, with other changes nearby).

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits)
  nfs: don't open in ->d_revalidate
  vfs: retry last component if opening stale dentry
  vfs: nameidata_to_filp(): don't throw away file on error
  vfs: nameidata_to_filp(): inline __dentry_open()
  vfs: do_dentry_open(): don't put filp
  vfs: split __dentry_open()
  vfs: do_last() common post lookup
  vfs: do_last(): add audit_inode before open
  vfs: do_last(): only return EISDIR for O_CREAT
  vfs: do_last(): check LOOKUP_DIRECTORY
  vfs: do_last(): make ENOENT exit RCU safe
  vfs: make follow_link check RCU safe
  vfs: do_last(): use inode variable
  vfs: do_last(): inline walk_component()
  vfs: do_last(): make exit RCU safe
  vfs: split do_lookup()
  Btrfs: move over to use ->update_time
  fs: introduce inode operation ->update_time
  reiserfs: get rid of resierfs_sync_super
  reiserfs: mark the superblock as dirty a bit later
  ...

1 files changed, 57 insertions, 19 deletions

diff --git a/fs/open.c b/fs/open.c
index d54301219d04..d6c79a0dffc7 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -654,10 +654,23 @@ static inline int __get_file_write_access(struct inode *inode,
         return error;
 }
 
-static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
-                                        struct file *f,
-                                        int (*open)(struct inode *, struct file *),
-                                        const struct cred *cred)
+int open_check_o_direct(struct file *f)
+{
+        /* NB: we're sure to have correct a_ops only after f_op->open */
+        if (f->f_flags & O_DIRECT) {
+                if (!f->f_mapping->a_ops ||
+                    ((!f->f_mapping->a_ops->direct_IO) &&
+                    (!f->f_mapping->a_ops->get_xip_mem))) {
+                        return -EINVAL;
+                }
+        }
+        return 0;
+}
+
+static struct file *do_dentry_open(struct dentry *dentry, struct vfsmount *mnt,
+                                   struct file *f,
+                                   int (*open)(struct inode *, struct file *),
+                                   const struct cred *cred)
 {
         static const struct file_operations empty_fops = {};
         struct inode *inode;
@@ -713,16 +726,6 @@ static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
 
         file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
 
-        /* NB: we're sure to have correct a_ops only after f_op->open */
-        if (f->f_flags & O_DIRECT) {
-                if (!f->f_mapping->a_ops ||
-                    ((!f->f_mapping->a_ops->direct_IO) &&
-                    (!f->f_mapping->a_ops->get_xip_mem))) {
-                        fput(f);
-                        f = ERR_PTR(-EINVAL);
-                }
-        }
-
         return f;
 
 cleanup_all:
@@ -744,12 +747,29 @@ cleanup_all:
         f->f_path.dentry = NULL;
         f->f_path.mnt = NULL;
 cleanup_file:
-        put_filp(f);
         dput(dentry);
         mntput(mnt);
         return ERR_PTR(error);
 }
 
+static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
+                                struct file *f,
+                                int (*open)(struct inode *, struct file *),
+                                const struct cred *cred)
+{
+        struct file *res = do_dentry_open(dentry, mnt, f, open, cred);
+        if (!IS_ERR(res)) {
+                int error = open_check_o_direct(f);
+                if (error) {
+                        fput(res);
+                        res = ERR_PTR(error);
+                }
+        } else {
+                put_filp(f);
+        }
+        return res;
+}
+
 /**
  * lookup_instantiate_filp - instantiates the open intent filp
  * @nd: pointer to nameidata
@@ -804,13 +824,31 @@ struct file *nameidata_to_filp(struct nameidata *nd)
 
         /* Pick up the filp from the open intent */
         filp = nd->intent.open.file;
-        nd->intent.open.file = NULL;
 
         /* Has the filesystem initialised the file for us? */
-        if (filp->f_path.dentry == NULL) {
+        if (filp->f_path.dentry != NULL) {
+                nd->intent.open.file = NULL;
+        } else {
+                struct file *res;
+
                 path_get(&nd->path);
-                filp = __dentry_open(nd->path.dentry, nd->path.mnt, filp,
-                                     NULL, cred);
+                res = do_dentry_open(nd->path.dentry, nd->path.mnt,
+                                     filp, NULL, cred);
+                if (!IS_ERR(res)) {
+                        int error;
+
+                        nd->intent.open.file = NULL;
+                        BUG_ON(res != filp);
+
+                        error = open_check_o_direct(filp);
+                        if (error) {
+                                fput(filp);
+                                filp = ERR_PTR(error);
+                        }
+                } else {
+                        /* Allow nd->intent.open.file to be recycled */
+                        filp = res;
+                }
         }
         return filp;
 }