[PATCH 6/7] nfs41: implement cb_recall_slot

andros
2010-01-14T22:45:20Z

From: Andy Adamson <andros@netapp.com>

Drain the fore channel and reset the max_slots to the new value.

Signed-off-by: Andy Adamson <andros@netapp.com>
---
fs/nfs/callback.h | 8 ++++++++
fs/nfs/callback_proc.c | 32 ++++++++++++++++++++++++++++++++
fs/nfs/callback_xdr.c | 22 +++++++++++++++++++++-
fs/nfs/nfs4_fs.h | 2 ++
fs/nfs/nfs4state.c | 43 +++++++++++++++++++++++++++++++++++++++++++
include/linux/nfs_fs_sb.h | 2 ++
6 files changed, 108 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index d4036be..85a7cfd 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -119,6 +119,14 @@ struct cb_recallanyargs {
};

extern unsigned nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy);
+
+struct cb_recallslotargs {
+ struct sockaddr *crsa_addr;
+ uint32_t crsa_target_max_slots;
+};
+extern unsigned nfs4_callback_recallslot(struct cb_recallslotargs *args,
+ void *dummy);
+
#endif /* CONFIG_NFS_V4_1 */

extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res);
diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 3cc2333..9318340 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -297,4 +297,36 @@ out:
dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
return status;
}
+
+/* Reduce the fore channel's max_slots to the target value */
+unsigned nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy)
+{
+ struct nfs_client *clp;
+ struct nfs4_slot_table *fc_tbl;
+ int status;
+
+ status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
+ clp = nfs_find_client(args->crsa_addr, 4);
+ if (clp == NULL)
+ goto out;
+
+ dprintk("NFS: CB_RECALL_SLOT request from %s target max slots %d\n",
+ rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR),
+ args->crsa_target_max_slots);
+
+ fc_tbl = &clp->cl_session->fc_slot_table;
+
+ status = htonl(NFS4ERR_BAD_HIGH_SLOT);
+ if (args->crsa_target_max_slots >= fc_tbl->max_slots ||
+ args->crsa_target_max_slots < 1)
+ goto out;
+
+ fc_tbl->target_max_slots = args->crsa_target_max_slots;
+ nfs41_handle_recall_slot(clp);
+ status = htonl(NFS4_OK);
+ nfs_put_client(clp); /* balance nfs_find_client */
+out:
+ dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
+ return status;
+}
#endif /* CONFIG_NFS_V4_1 */
diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index 08b430d..8e66e20 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -24,6 +24,7 @@
#define CB_OP_SEQUENCE_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
4 + 1 + 3)
#define CB_OP_RECALLANY_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ)
+#define CB_OP_RECALLSLOT_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ)
#endif /* CONFIG_NFS_V4_1 */

#define NFSDBG_FACILITY NFSDBG_CALLBACK
@@ -349,6 +350,20 @@ static unsigned decode_recallany_args(struct svc_rqst *rqstp,
return 0;
}

+static unsigned decode_recallslot_args(struct svc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ struct cb_recallslotargs *args)
+{
+ __be32 *p;
+
+ args->crsa_addr = svc_addr(rqstp);
+ p = read_buf(xdr, 4);
+ if (unlikely(p == NULL))
+ return htonl(NFS4ERR_BADXDR);
+ args->crsa_target_max_slots = ntohl(*p++);
+ return 0;
+}
+
#endif /* CONFIG_NFS_V4_1 */

static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
@@ -557,6 +572,7 @@ preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
case OP_CB_RECALL:
case OP_CB_SEQUENCE:
case OP_CB_RECALL_ANY:
+ case OP_CB_RECALL_SLOT:
*op = &callback_ops[op_nr];
break;

@@ -565,7 +581,6 @@ preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
case OP_CB_NOTIFY:
case OP_CB_PUSH_DELEG:
case OP_CB_RECALLABLE_OBJ_AVAIL:
- case OP_CB_RECALL_SLOT:
case OP_CB_WANTS_CANCELLED:
case OP_CB_NOTIFY_LOCK:
return htonl(NFS4ERR_NOTSUPP);
@@ -734,6 +749,11 @@ static struct callback_op callback_ops[] = {
.decode_args = (callback_decode_arg_t)decode_recallany_args,
.res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
},
+ [OP_CB_RECALL_SLOT] = {
+ .process_op = (callback_process_op_t)nfs4_callback_recallslot,
+ .decode_args = (callback_decode_arg_t)decode_recallslot_args,
+ .res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
+ },
#endif /* CONFIG_NFS_V4_1 */
};

diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 865265b..cd93dfc 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -46,6 +46,7 @@ enum nfs4_client_state {
NFS4CLNT_DELEGRETURN,
NFS4CLNT_SESSION_RESET,
NFS4CLNT_SESSION_DRAINING,
+ NFS4CLNT_RECALL_SLOT,
};

/*
@@ -278,6 +279,7 @@ extern void nfs4_schedule_state_recovery(struct nfs_client *);
extern void nfs4_schedule_state_manager(struct nfs_client *);
extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state);
extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
+extern void nfs41_handle_recall_slot(struct nfs_client *clp);
extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
extern void nfs4_copy_stateid(nfs4_stateid *, struct nfs4_state *, fl_owner_t);
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 6d263ed..df03355 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1249,6 +1249,12 @@ static int nfs4_reclaim_lease(struct nfs_client *clp)
}

#ifdef CONFIG_NFS_V4_1
+void nfs41_handle_recall_slot(struct nfs_client *clp)
+{
+ set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
+ nfs4_schedule_state_recovery(clp);
+}
+
void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
{
if (!flags)
@@ -1299,6 +1305,34 @@ out:
return status;
}

+static int nfs4_recall_slot(struct nfs_client *clp)
+{
+ struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
+ struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
+ struct nfs4_slot *new, *old;
+ int i;
+
+ nfs4_begin_drain_session(clp);
+ new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
+ GFP_KERNEL);
+ if (!new)
+ return -ENOMEM;
+
+ spin_lock(&fc_tbl->slot_tbl_lock);
+ for (i = 0; i < fc_tbl->target_max_slots; i++)
+ new[i].seq_nr = fc_tbl->slots[i].seq_nr;
+ old = fc_tbl->slots;
+ fc_tbl->slots = new;
+ fc_tbl->max_slots = fc_tbl->target_max_slots;
+ fc_tbl->target_max_slots = 0;
+ fc_attrs->max_reqs = fc_tbl->max_slots;
+ spin_unlock(&fc_tbl->slot_tbl_lock);
+
+ kfree(old);
+ nfs4_end_drain_session(clp);
+ return 0;
+}
+
#else /* CONFIG_NFS_V4_1 */
static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
@@ -1397,6 +1431,15 @@ static void nfs4_state_manager(struct nfs_client *clp)
nfs_client_return_marked_delegations(clp);
continue;
}
+ /* Recall session slots */
+ if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
+ && nfs4_has_session(clp)) {
+ status = nfs4_recall_slot(clp);
+ if (status < 0)
+ goto out_error;
+ continue;
+ }
+

nfs4_clear_state_manager_bit(clp);
/* Did we race with an attempt to give us more work? */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 34fc6be..ecd9e6c 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -193,6 +193,8 @@ struct nfs4_slot_table {
int max_slots; /* # slots in table */
int highest_used_slotid; /* sent to server on each SEQ.
* op for dynamic resizing */
+ int target_max_slots; /* Set by CB_RECALL_SLOT as
+ * the new max_slots */
};

static inline int slot_idx(struct nfs4_slot_table *tbl, struct nfs4_slot *sp)
--
1.6.5.2