[PATCH 003 of 8] knfsd: exportfs: add procedural interface for NFSD

NeilBrown
2007-05-15T07:17:06Z

Currently NFSD calls directly into filesystems through the
export_operations structure. I plan to change this interface
in various ways in later patches, and want to avoid the export
of the default operations to NFSD, so this patch adds two
simple exportfs_encode_fh/exportfs_decode_fh helpers for NFSD
to call instead of poking into exportfs guts.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
./fs/exportfs/expfs.c | 22 +++++++++++++++++++++-
./fs/nfsd/nfsfh.c | 18 +++++-------------
./include/linux/exportfs.h | 7 +++++++
3 files changed, 33 insertions(+), 14 deletions(-)

diff .prev/fs/exportfs/expfs.c ./fs/exportfs/expfs.c
--- .prev/fs/exportfs/expfs.c 2007-05-14 11:15:29.000000000 +1000
+++ ./fs/exportfs/expfs.c 2007-05-14 11:15:31.000000000 +1000
@@ -3,6 +3,7 @@
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/module.h>
+#include <linux/mount.h>
#include <linux/namei.h>

struct export_operations export_op_default;
@@ -468,6 +469,26 @@ static struct dentry *export_decode_fh(s
acceptable, context);
}

+int exportfs_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len,
+ int connectable)
+{
+ struct export_operations *nop = dentry->d_sb->s_export_op;
+
+ return CALL(nop, encode_fh)(dentry, fh, max_len, connectable);
+}
+EXPORT_SYMBOL_GPL(exportfs_encode_fh);
+
+struct dentry *exportfs_decode_fh(struct vfsmount *mnt, __u32 *fh, int fh_len,
+ int fileid_type, int (*acceptable)(void *, struct dentry *),
+ void *context)
+{
+ struct export_operations *nop = mnt->mnt_sb->s_export_op;
+
+ return CALL(nop, decode_fh)(mnt->mnt_sb, fh, fh_len, fileid_type,
+ acceptable, context);
+}
+EXPORT_SYMBOL_GPL(exportfs_decode_fh);
+
struct export_operations export_op_default = {
.decode_fh = export_decode_fh,
.encode_fh = export_encode_fh,
@@ -477,7 +498,6 @@ struct export_operations export_op_defau
.get_dentry = get_dentry,
};

-EXPORT_SYMBOL(export_op_default);
EXPORT_SYMBOL(find_exported_dentry);

MODULE_LICENSE("GPL");

diff .prev/fs/nfsd/nfsfh.c ./fs/nfsd/nfsfh.c
--- .prev/fs/nfsd/nfsfh.c 2007-05-14 11:15:23.000000000 +1000
+++ ./fs/nfsd/nfsfh.c 2007-05-14 11:15:31.000000000 +1000
@@ -28,10 +28,6 @@
static int nfsd_nr_verified;
static int nfsd_nr_put;

-extern struct export_operations export_op_default;
-
-#define CALL(ops,fun) ((ops->fun)?(ops->fun):export_op_default.fun)
-
/*
* our acceptability function.
* if NOSUBTREECHECK, accept anything
@@ -212,11 +208,9 @@ fh_verify(struct svc_rqst *rqstp, struct
if (fileid_type == 0)
dentry = dget(exp->ex_dentry);
else {
- struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op;
- dentry = CALL(nop,decode_fh)(exp->ex_mnt->mnt_sb,
- datap, data_left,
- fileid_type,
- nfsd_acceptable, exp);
+ dentry = exportfs_decode_fh(exp->ex_mnt, datap,
+ data_left, fileid_type,
+ nfsd_acceptable, exp);
}
if (dentry == NULL)
goto out;
@@ -287,15 +281,13 @@ out:
static inline int _fh_update(struct dentry *dentry, struct svc_export *exp,
__u32 *datap, int *maxsize)
{
- struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op;
-
if (dentry == exp->ex_dentry) {
*maxsize = 0;
return 0;
}

- return CALL(nop,encode_fh)(dentry, datap, maxsize,
- !(exp->ex_flags&NFSEXP_NOSUBTREECHECK));
+ return exportfs_encode_fh(dentry, datap, maxsize,
+ !(exp->ex_flags & NFSEXP_NOSUBTREECHECK));
}

/*

diff .prev/include/linux/exportfs.h ./include/linux/exportfs.h
--- .prev/include/linux/exportfs.h 2007-05-14 11:15:23.000000000 +1000
+++ ./include/linux/exportfs.h 2007-05-14 11:15:31.000000000 +1000
@@ -5,6 +5,7 @@

struct dentry;
struct super_block;
+struct vfsmount;

/**
@@ -116,4 +117,10 @@ extern struct dentry *find_exported_dent
void *parent, int (*acceptable)(void *context, struct dentry *de),
void *context);

+extern int exportfs_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len,
+ int connectable);
+extern struct dentry *exportfs_decode_fh(struct vfsmount *mnt, __u32 *fh,
+ int fh_len, int fileid_type, int (*acceptable)(void *, struct dentry *),
+ void *context);
+
#endif /* LINUX_EXPORTFS_H */