commit fb89b45cdfdc8bdab93986f1bc1474e313295c31
author Dominique Martinet <dominique.martinet@cea.fr> Fri Jan 10 13:44:09 2014 +0100
committer Eric Van Hensbergen <ericvh@gmail.com> Fri Jan 10 09:20:51 2014 -0600
tree c19ec0f84315c6dc77ca2447f58e2508b76ce88a
parent f94741fd2832e7abc30fbf6dc13ed627c1fcc01a

9P: introduction of a new cache=mmap model.

 - Add cache=mmap option
 - Make mmap read-write while keeping it as synchronous as possible
 - Build writeback fid on mmap creation if it is writable

Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

fs/9p/vfs_inode.c

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index af7d531..bb7991c 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -299,15 +299,22 @@
 	case S_IFREG:
 		if (v9fs_proto_dotl(v9ses)) {
 			inode->i_op = &v9fs_file_inode_operations_dotl;
-			if (v9ses->cache)
+			if (v9ses->cache == CACHE_LOOSE ||
+			    v9ses->cache == CACHE_FSCACHE)
 				inode->i_fop =
 					&v9fs_cached_file_operations_dotl;
+			else if (v9ses->cache == CACHE_MMAP)
+				inode->i_fop = &v9fs_mmap_file_operations_dotl;
 			else
 				inode->i_fop = &v9fs_file_operations_dotl;
 		} else {
 			inode->i_op = &v9fs_file_inode_operations;
-			if (v9ses->cache)
-				inode->i_fop = &v9fs_cached_file_operations;
+			if (v9ses->cache == CACHE_LOOSE ||
+			    v9ses->cache == CACHE_FSCACHE)
+				inode->i_fop =
+					&v9fs_cached_file_operations;
+			else if (v9ses->cache == CACHE_MMAP)
+				inode->i_fop = &v9fs_mmap_file_operations;
 			else
 				inode->i_fop = &v9fs_file_operations;
 		}
@@ -810,7 +817,7 @@
 	 * unlink. For cached mode create calls request for new
 	 * inode. But with cache disabled, lookup should do this.
 	 */
-	if (v9ses->cache)
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 		inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 	else
 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
@@ -876,7 +883,8 @@
 	v9fs_invalidate_inode_attr(dir);
 	v9inode = V9FS_I(dentry->d_inode);
 	mutex_lock(&v9inode->v_mutex);
-	if (v9ses->cache && !v9inode->writeback_fid &&
+	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
+	    !v9inode->writeback_fid &&
 	    ((flags & O_ACCMODE) != O_RDONLY)) {
 		/*
 		 * clone a fid and add it to writeback_fid
@@ -899,7 +907,7 @@
 		goto error;
 
 	file->private_data = fid;
-	if (v9ses->cache)
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 		v9fs_cache_inode_set_cookie(dentry->d_inode, file);
 
 	*opened |= FILE_CREATED;
@@ -1477,7 +1485,7 @@
 	 */
 	i_size = inode->i_size;
 	v9fs_stat2inode(st, inode, inode->i_sb);
-	if (v9ses->cache)
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 		inode->i_size = i_size;
 	spin_unlock(&inode->i_lock);
 out: