NFS refactor nfs_find_client and reference client across callback processing
Fixes a bug where the nfs_client could be freed during callback processing.
Refactor nfs_find_client to use minorversion specific means to locate the
correct nfs_client structure.
In the NFS layer, V4.0 clients are found using the callback_ident field in the
CB_COMPOUND header. V4.1 clients are found using the sessionID in the
CB_SEQUENCE operation which is also compared against the sessionID associated
with the back channel thread after a successful CREATE_SESSION.
Each of these methods finds the one an only nfs_client associated
with the incoming callback request - so nfs_find_client_next is not needed.
In the RPC layer, the pg_authenticate call needs to find the nfs_client. For
the v4.0 callback service, the callback identifier has not been decoded so a
search by address, version, and minorversion is used. The sessionid for the
sessions based callback service has (usually) not been set for the
pg_authenticate on a CB_NULL call which can be sent prior to the return
of a CREATE_SESSION call, so the sessionid associated with the back channel
thread is not used to find the client in pg_authenticate for CB_NULL calls.
Pass the referenced nfs_client to each CB_COMPOUND operation being proceesed
via the new cb_process_state structure. The reference is held across
cb_compound processing.
Use the new cb_process_state struct to move the NFS4ERR_RETRY_UNCACHED_REP
processing from process_op into nfs4_callback_sequence where it belongs.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 58d61a8..25e8802 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -34,10 +34,17 @@
OP_CB_ILLEGAL = 10044,
};
+struct cb_process_state {
+ __be32 drc_status;
+ struct nfs_client *clp;
+ struct nfs4_sessionid *svc_sid; /* v4.1 callback service sessionid */
+};
+
struct cb_compound_hdr_arg {
unsigned int taglen;
const char *tag;
unsigned int minorversion;
+ unsigned int cb_ident; /* v4.0 callback identifier */
unsigned nops;
};
@@ -103,8 +110,9 @@
uint32_t csr_target_highestslotid;
};
-extern unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
- struct cb_sequenceres *res);
+extern __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
+ struct cb_sequenceres *res,
+ struct cb_process_state *cps);
extern int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation,
const nfs4_stateid *stateid);
@@ -118,19 +126,25 @@
uint32_t craa_type_mask;
};
-extern unsigned nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy);
+extern __be32 nfs4_callback_recallany(struct cb_recallanyargs *args,
+ void *dummy,
+ struct cb_process_state *cps);
struct cb_recallslotargs {
struct sockaddr *crsa_addr;
uint32_t crsa_target_max_slots;
};
-extern unsigned nfs4_callback_recallslot(struct cb_recallslotargs *args,
- void *dummy);
+extern __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args,
+ void *dummy,
+ struct cb_process_state *cps);
#endif /* CONFIG_NFS_V4_1 */
-extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res);
-extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy);
+extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
+ struct cb_getattrres *res,
+ struct cb_process_state *cps);
+extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
+ struct cb_process_state *cps);
#ifdef CONFIG_NFS_V4
extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);