diff options
| author | Chuck Lever <chuck.lever@oracle.com> | 2012-05-21 22:45:41 -0400 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-05-22 16:45:46 -0400 |
| commit | f092075dd33ea04000590e8ffea65c2e7d03d764 (patch) | |
| tree | 626ce6b85084d50e9d2d81e32850e494eadbc8cb /fs/nfs/nfs4xdr.c | |
| parent | 2c820d9a97f07b273b2c8a5960bd52b1b5864c68 (diff) | |
NFS: Always use the same SETCLIENTID boot verifier
Currently our NFS client assigns a unique SETCLIENTID boot verifier
for each server IP address it knows about. It's set to CURRENT_TIME
when the struct nfs_client for that server IP is created.
During the SETCLIENTID operation, our client also presents an
nfs_client_id4 string to servers, as an identifier on which the server
can hang all of this client's NFSv4 state. Our client's
nfs_client_id4 string is unique for each server IP address.
An NFSv4 server is obligated to wipe all NFSv4 state associated with
an nfs_client_id4 string when the client presents the same
nfs_client_id4 string along with a changed SETCLIENTID boot verifier.
When our client unmounts the last of a server's shares, it destroys
that server's struct nfs_client. The next time the client mounts that
NFS server, it creates a fresh struct nfs_client with a fresh boot
verifier. On seeing the fresh verifer, the server wipes any previous
NFSv4 state associated with that nfs_client_id4.
However, NFSv4.1 clients are supposed to present the same
nfs_client_id4 string to all servers. And, to support Transparent
State Migration, the same nfs_client_id4 string should be presented
to all NFSv4.0 servers so they recognize that migrated state for this
client belongs with state a server may already have for this client.
(This is known as the Uniform Client String model).
If the nfs_client_id4 string is the same but the boot verifier changes
for each server IP address, SETCLIENTID and EXCHANGE_ID operations
from such a client could unintentionally result in a server wiping a
client's previously obtained lease.
Thus, if our NFS client is going to use a fixed nfs_client_id4 string,
either for NFSv4.0 or NFSv4.1 mounts, our NFS client should use a
boot verifier that does not change depending on server IP address.
Replace our current per-nfs_client boot verifier with a per-nfs_net
boot verifier.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/nfs4xdr.c')
| -rw-r--r-- | fs/nfs/nfs4xdr.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index db040e97193..12b99825a1c 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -53,9 +53,11 @@ #include <linux/nfs4.h> #include <linux/nfs_fs.h> #include <linux/nfs_idmap.h> + #include "nfs4_fs.h" #include "internal.h" #include "pnfs.h" +#include "netns.h" #define NFSDBG_FACILITY NFSDBG_XDR @@ -1702,6 +1704,7 @@ static void encode_create_session(struct xdr_stream *xdr, char machine_name[NFS4_MAX_MACHINE_NAME_LEN]; uint32_t len; struct nfs_client *clp = args->client; + struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id); u32 max_resp_sz_cached; /* @@ -1743,7 +1746,7 @@ static void encode_create_session(struct xdr_stream *xdr, *p++ = cpu_to_be32(RPC_AUTH_UNIX); /* auth_sys */ /* authsys_parms rfc1831 */ - *p++ = cpu_to_be32((u32)clp->cl_boot_time.tv_nsec); /* stamp */ + *p++ = (__be32)nn->boot_time.tv_nsec; /* stamp */ p = xdr_encode_opaque(p, machine_name, len); *p++ = cpu_to_be32(0); /* UID */ *p++ = cpu_to_be32(0); /* GID */ |