From: Andy Adamson <andros@xxxxxxxxxx>
Save the struct nfsd4_compound_state and set the save_state callback for
each request for potential deferral handling.
If an NFSv4 operation causes a deferral, the save_state callback is called
by svc_defer which saves the defer_data with the deferral, and sets the
restore_state deferral callback.
fh_put is called so that the deferral is not referencing the file handles,
allowing umount of the file system.
Use a slab cache for nfsd4_compound_state allocation.
Signed-off-by: Andy Adamson<andros@xxxxxxxxxx>
Signed-off-by: Benny Halevy <bhalevy@xxxxxxxxxxx>
---
fs/nfsd/nfs4proc.c | 63 ++++++++++++++++++++++++--------------------
fs/nfsd/nfs4state.c | 40 ++++++++++++++++++++++++++++
include/linux/nfsd/xdr4.h | 5 +++
3 files changed, 79 insertions(+), 29 deletions(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 72fd645..deefba1 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -860,29 +860,6 @@ static inline void nfsd4_increment_op_stats(u32 opnum)
nfsdstats.nfs4_opcount[opnum]++;
}
-static void cstate_free(struct nfsd4_compound_state *cstate)
-{
- if (cstate == NULL)
- return;
- fh_put(&cstate->current_fh);
- fh_put(&cstate->save_fh);
- BUG_ON(cstate->replay_owner);
- kfree(cstate);
-}
-
-static struct nfsd4_compound_state *cstate_alloc(void)
-{
- struct nfsd4_compound_state *cstate;
-
- cstate = kmalloc(sizeof(struct nfsd4_compound_state), GFP_KERNEL);
- if (cstate == NULL)
- return NULL;
- fh_init(&cstate->current_fh, NFS4_FHSIZE);
- fh_init(&cstate->save_fh, NFS4_FHSIZE);
- cstate->replay_owner = NULL;
- return cstate;
-}
-
/*
* RPC restore deferral state callback
*/
@@ -891,8 +868,7 @@ nfsd4_release_deferred_state(struct svc_deferred_req *dreq)
{
dprintk("--> %s dreq %p\n", __func__, dreq);
- nfsd4_clear_respages(dreq->respages, dreq->resused);
- cstate_free(dreq->defer_data); /* kfree the cstate */
+ nfsd4_cstate_free(dreq->defer_data, dreq); /* kfree the cstate */
}
/*
@@ -961,11 +937,11 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
struct nfsd4_compoundargs *args,
struct nfsd4_compoundres *resp)
{
- struct nfsd4_op *op = NULL;
+ struct nfsd4_op *op;
struct nfsd4_operation *opdesc;
struct nfsd4_compound_state *cstate = NULL;
int slack_bytes;
- __be32 status;
+ __be32 status = nfs_ok;
#if defined(CONFIG_NFSD_V4_1)
struct current_session *current_ses = NULL;
#endif /* CONFIG_NFSD_V4_1 */
@@ -990,10 +966,25 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
goto out;
status = nfserr_resource;
- cstate = cstate_alloc();
+ cstate = nfsd4_cstate_alloc(rqstp);
if (cstate == NULL)
goto out;
+ if (rqstp->rq_deferred && rqstp->rq_deferred->defer_data) {
+ dprintk("%s Resuming deferred processing\n", __func__);
+ resp->opcnt = cstate->last_op_cnt;
+ resp->p = cstate->last_op_p;
+
+ /* verify the current and save file handles that were
+ * fh_put at deferral. */
+ fh_verify(rqstp, &cstate->current_fh, 0, NFSD_MAY_NOP);
+ fh_verify(rqstp, &cstate->save_fh, 0, NFSD_MAY_NOP);
+ }
+
+ /* set for potential deferral */
+ rqstp->rq_defer_data = cstate;
+ rqstp->rq_save_state = nfsd4_save_deferred_state;
+
#if defined(CONFIG_NFSD_V4_1)
if (args->minorversion == 1) {
/* FIXME: use kmem_cache */
@@ -1007,6 +998,7 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
status = nfs_ok;
while (!status && resp->opcnt < args->opcnt) {
+ cstate->last_op_p = resp->p;
op = &args->ops[resp->opcnt++];
dprintk("nfsv4 compound op #%d/%d: %d (%s)\n",
@@ -1076,6 +1068,19 @@ encode_op:
nfsd4_increment_op_stats(op->opnum);
}
+ /* Done with any potential deferral */
+ rqstp->rq_defer_data = cstate;
+ rqstp->rq_save_state = NULL;
+
+ if (status == nfserr_dropit) {
+ dprintk("%s Drop it!\n", __func__);
+
+ /* svc_defer() has called the rq_save_state() callback
+ * to cache the partially processed compound. */
+ cstate->last_op_cnt = resp->opcnt - 1;
+ return status;
+ }
+
out_free:
#if defined(CONFIG_NFSD_V4_1)
if (current_ses) {
@@ -1092,7 +1097,7 @@ out_free:
kfree(current_ses);
}
#endif /* CONFIG_NFSD_V4_1 */
- cstate_free(cstate);
+ nfsd4_cstate_free(cstate, rqstp->rq_deferred);
out:
nfsd4_release_compoundargs(args);
dprintk("nfsv4 compound returned %d\n", ntohl(status));
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index ae6de38..8fd7704 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -101,6 +101,7 @@ static struct kmem_cache *stateowner_slab = NULL;
static struct kmem_cache *file_slab = NULL;
static struct kmem_cache *stateid_slab = NULL;
static struct kmem_cache *deleg_slab = NULL;
+static struct kmem_cache *cstate_slab;
#define BUG_ON_UNLOCKED_STATE() BUG_ON(mutex_trylock(&client_mutex))
@@ -480,6 +481,40 @@ free_session(struct kref *kref)
}
#endif /* CONFIG_NFSD_V4_1 */
+void
+nfsd4_cstate_free(struct nfsd4_compound_state *cstate,
+ struct svc_deferred_req *dreq)
+{
+ if (dreq && dreq->release_state)
+ nfsd4_clear_respages(dreq->respages, dreq->resused);
+ if (cstate == NULL)
+ return;
+ fh_put(&cstate->current_fh);
+ fh_put(&cstate->save_fh);
+ BUG_ON(cstate->replay_owner);
+ kmem_cache_free(cstate_slab, cstate);
+}
+
+struct nfsd4_compound_state *
+nfsd4_cstate_alloc(struct svc_rqst *rqstp)
+{
+ struct nfsd4_compound_state *cstate;
+
+ if (rqstp->rq_deferred && rqstp->rq_deferred->defer_data) {
+ dprintk("%s Revisit deferred request\n", __func__);
+ cstate = rqstp->rq_deferred->defer_data;
+ goto out;
+ }
+ cstate = kmem_cache_alloc(cstate_slab, GFP_KERNEL);
+ if (cstate == NULL)
+ return NULL;
+ fh_init(&cstate->current_fh, NFS4_FHSIZE);
+ fh_init(&cstate->save_fh, NFS4_FHSIZE);
+ cstate->replay_owner = NULL;
+out:
+ return cstate;
+}
+
static inline void
renew_client(struct nfs4_client *clp)
{
@@ -1529,6 +1564,7 @@ nfsd4_free_slabs(void)
nfsd4_free_slab(&file_slab);
nfsd4_free_slab(&stateid_slab);
nfsd4_free_slab(&deleg_slab);
+ nfsd4_free_slab(&cstate_slab);
}
static int
@@ -1550,6 +1586,10 @@ nfsd4_init_slabs(void)
sizeof(struct nfs4_delegation), 0, 0, NULL);
if (deleg_slab == NULL)
goto out_nomem;
+ cstate_slab = kmem_cache_create("nfsd4_compound_states",
+ sizeof(struct nfsd4_compound_state), 0, 0, NULL);
+ if (cstate_slab == NULL)
+ goto out_nomem;
return 0;
out_nomem:
nfsd4_free_slabs();
diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h
index 01fb139..a0b4f00 100644
--- a/include/linux/nfsd/xdr4.h
+++ b/include/linux/nfsd/xdr4.h
@@ -48,6 +48,8 @@ struct nfsd4_compound_state {
struct svc_fh current_fh;
struct svc_fh save_fh;
struct nfs4_stateowner *replay_owner;
+ __be32 *last_op_p;
+ u32 last_op_cnt;
#if defined(CONFIG_NFSD_V4_1)
struct current_session *current_ses;
#endif /* CONFIG_NFSD_V4_1 */
@@ -520,6 +522,9 @@ extern void nfsd4_cache_rqst_pages(struct svc_rqst *rqstp,
struct page **respages, short *resused);
extern void nfsd4_restore_rqst_pages(struct svc_rqst *rqstp,
struct page **respages, short resused);
+extern struct nfsd4_compound_state *nfsd4_cstate_alloc(struct svc_rqst *rqstp);
+extern void nfsd4_cstate_free(struct nfsd4_compound_state *cstate,
+ struct svc_deferred_req *dreq);
extern __be32 nfsd4_setclientid(struct svc_rqst *rqstp,
struct nfsd4_compound_state *,
struct nfsd4_setclientid *setclid);
--
1.6.0.2
--
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