Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw

Pull GFS2 updates from Steven Whitehouse:
 "There are a few bug fixes for various, mostly very minor corner cases,
  plus some interesting new features.

  The new features include atomic_open whose main benefit will be the
  reduction in locking overhead in case of combined lookup/create and
  open operations, sorting the log buffer lists by block number to
  improve the efficiency of AIL writeback, and aggressively issuing
  revokes in gfs2_log_flush to reduce overhead when dropping glocks."

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw:
  GFS2: Reserve journal space for quota change in do_grow
  GFS2: Fix fstrim boundary conditions
  GFS2: fix warning message
  GFS2: aggressively issue revokes in gfs2_log_flush
  GFS2: fix regression in dir_double_exhash
  GFS2: Add atomic_open support
  GFS2: Only do one directory search on create
  GFS2: fix error propagation in init_threads()
  GFS2: Remove no-op wrapper function
  GFS2: Cocci spatch "ptr_ret.spatch"
  GFS2: Eliminate gfs2_rg_lops
  GFS2: Sort buffer lists by inplace block number

1 files changed, 46 insertions, 23 deletions

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index b3333371aebb..f99f9e8a325f 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -531,21 +531,30 @@ static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
 }
 
 /**
- * gfs2_open - open a file
- * @inode: the inode to open
- * @file: the struct file for this opening
+ * gfs2_open_common - This is common to open and atomic_open
+ * @inode: The inode being opened
+ * @file: The file being opened
  *
- * Returns: errno
+ * This maybe called under a glock or not depending upon how it has
+ * been called. We must always be called under a glock for regular
+ * files, however. For other file types, it does not matter whether
+ * we hold the glock or not.
+ *
+ * Returns: Error code or 0 for success
  */
 
-static int gfs2_open(struct inode *inode, struct file *file)
+int gfs2_open_common(struct inode *inode, struct file *file)
 {
-	struct gfs2_inode *ip = GFS2_I(inode);
-	struct gfs2_holder i_gh;
 	struct gfs2_file *fp;
-	int error;
+	int ret;
 
-	fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
+	if (S_ISREG(inode->i_mode)) {
+		ret = generic_file_open(inode, file);
+		if (ret)
+			return ret;
+	}
+
+	fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
 	if (!fp)
 		return -ENOMEM;
 
@@ -553,29 +562,43 @@ static int gfs2_open(struct inode *inode, struct file *file)
 
 	gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
 	file->private_data = fp;
+	return 0;
+}
+
+/**
+ * gfs2_open - open a file
+ * @inode: the inode to open
+ * @file: the struct file for this opening
+ *
+ * After atomic_open, this function is only used for opening files
+ * which are already cached. We must still get the glock for regular
+ * files to ensure that we have the file size uptodate for the large
+ * file check which is in the common code. That is only an issue for
+ * regular files though.
+ *
+ * Returns: errno
+ */
+
+static int gfs2_open(struct inode *inode, struct file *file)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_holder i_gh;
+	int error;
+	bool need_unlock = false;
 
 	if (S_ISREG(ip->i_inode.i_mode)) {
 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
 					   &i_gh);
 		if (error)
-			goto fail;
+			return error;
+		need_unlock = true;
+	}
 
-		if (!(file->f_flags & O_LARGEFILE) &&
-		    i_size_read(inode) > MAX_NON_LFS) {
-			error = -EOVERFLOW;
-			goto fail_gunlock;
-		}
+	error = gfs2_open_common(inode, file);
 
+	if (need_unlock)
 		gfs2_glock_dq_uninit(&i_gh);
-	}
-
-	return 0;
 
-fail_gunlock:
-	gfs2_glock_dq_uninit(&i_gh);
-fail:
-	file->private_data = NULL;
-	kfree(fp);
 	return error;
 }