[PATCH 13/22] pnfs_submit: use fsdata to pass lseg

[Fred Isaman <iisaman@netapp.com>]

Preparing for LAYUTGET invocation in nfs_write_begin to be the
only invocation in the write path.

It isn't used at all yet, but it should be properly referenced/dereferenced

Signed-off-by: Fred Isaman <iisaman@netapp.com>
---
 fs/nfs/file.c |   16 +++++++++++++---
 1 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 3ec9abb..03a1b3b 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -416,6 +416,8 @@ static int nfs_write_begin(struct file *file, struct address_space *mapping,
 		file->f_path.dentry->d_name.name,
 		mapping->host->i_ino, len, (long long) pos);
 
+	pnfs_update_layout(mapping->host, NULL, NFS4_MAX_UINT64, 0, IOMODE_RW,
+			   (struct pnfs_layout_segment **) fsdata);
 start:
 	/*
 	 * Prevent starvation issues if someone is doing a consistency
@@ -424,11 +426,13 @@ start:
 	ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING,
 			nfs_wait_bit_killable, TASK_KILLABLE);
 	if (ret)
-		return ret;
+		goto out;
 
 	page = grab_cache_page_write_begin(mapping, index, flags);
-	if (!page)
-		return -ENOMEM;
+	if (!page) {
+		ret = -ENOMEM;
+		goto out;
+	}
 	*pagep = page;
 
 	ret = nfs_flush_incompatible(file, page);
@@ -443,6 +447,11 @@ start:
 		if (!ret)
 			goto start;
 	}
+ out:
+	if (ret) {
+		put_lseg(*fsdata);
+		*fsdata = NULL;
+	}
 	return ret;
 }
 
@@ -482,6 +491,7 @@ static int nfs_write_end(struct file *file, struct address_space *mapping,
 
 	unlock_page(page);
 	page_cache_release(page);
+	put_lseg(fsdata);
 
 	if (status < 0)
 		return status;
-- 
1.6.6.1