gfapi: object handle based API extensions

There is an ongoing effort to integrate NFS Ganesha (
https://github.com/nfs-ganesha/nfs-ganesha/wiki ) with GlusterFS as one of
the file system back ends.

Towards this we need extensions to gfapi that can handle object based
operations. Meaning, instead of using full paths or relative paths from
cwd, it is required that we can work with APIs, like the *at POSIX
variants, to be able to create, lookup, open etc. files and directories.
Hence the objects are the files or directories themselves and we give out
handles to these objects that can be used for further operations.

This code drop is an initial implementation of the proposed APIs.

The new APIs are implemented as glfs_h_XXX variants in the file
glfs-handleops.c to mirror glfs-fops.c style. The code leverages holding
onto inode references and doling these out as opaque/cookie type objects to
the callers, to enable them to be used as handles in other operations.

An fd based approach was considered, but due to the extra footprint that
the fd structure and its counterparts would incur, this was dropped to take
the approach of holding inode references themselves.

Tested by extending glfsxmp.c to invoke and exercise the added APIs, and
further tested with a reference integration of the same as an FSAL with NFS
Ganesha.

Change-Id: I23629c99e905b54070fa2e6565147812e5f3fa5d
BUG: 1016000
Signed-off-by: R.Shyamsundar <srangana@redhat.com>
Reviewed-on: http://review.gluster.org/5936
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

1 files changed, 3 insertions, 15 deletions

diff --git a/api/src/glfs-fops.c b/api/src/glfs-fops.c
index 8119cc4f693..9070661b99e 100644
--- a/api/src/glfs-fops.c
+++ b/api/src/glfs-fops.c
@@ -14,20 +14,8 @@
 #include "syncop.h"
 #include "glfs.h"
 
-#define DEFAULT_REVAL_COUNT 1
 
-#define ESTALE_RETRY(ret,errno,reval,loc,label) do {	\
-	if (ret == -1 && errno == ESTALE) {	        \
-		if (reval < DEFAULT_REVAL_COUNT) {	\
-			reval++;			\
-			loc_wipe (loc);			\
-			goto label;			\
-		}					\
-	}						\
-	} while (0)
-
-
-static int
+int
 glfs_loc_link (loc_t *loc, struct iatt *iatt)
 {
 	int ret = -1;
@@ -52,7 +40,7 @@ glfs_loc_link (loc_t *loc, struct iatt *iatt)
 }
 
 
-static void
+void
 glfs_iatt_to_stat (struct glfs *fs, struct iatt *iatt, struct stat *stat)
 {
 	iatt_to_stat (iatt, stat);
@@ -60,7 +48,7 @@ glfs_iatt_to_stat (struct glfs *fs, struct iatt *iatt, struct stat *stat)
 }
 
 
-static int
+int
 glfs_loc_unlink (loc_t *loc)
 {
 	inode_unlink (loc->inode, loc->parent, loc->name);