nfsd4: do idr preallocation with stateid allocation
Move idr preallocation out of stateid initialization, into stateid
allocation, so that we no longer have to handle any errors from the
former.
This is a little subtle due to the way the idr code manages these
preallocated items--document that in comments.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index ae5d250..1f8c781 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -215,13 +215,12 @@
int new_stid;
int error;
- if (!idr_pre_get(stateids, GFP_KERNEL))
- return -ENOMEM;
-
error = idr_get_new_above(stateids, stid, min_stateid, &new_stid);
/*
- * All this code is currently serialized; the preallocation
- * above should still be ours:
+ * Note: the necessary preallocation was done in
+ * nfs4_alloc_stateid(). The idr code caps the number of
+ * preallocations that can exist at a time, but the state lock
+ * prevents anyone from using ours before we get here:
*/
BUG_ON(error);
/*
@@ -240,7 +239,7 @@
return new_stid;
}
-static inline __be32 init_stid(struct nfs4_stid *stid, struct nfs4_client *cl, unsigned char type)
+static void init_stid(struct nfs4_stid *stid, struct nfs4_client *cl, unsigned char type)
{
stateid_t *s = &stid->sc_stateid;
int new_id;
@@ -249,12 +248,24 @@
stid->sc_client = cl;
s->si_opaque.so_clid = cl->cl_clientid;
new_id = get_new_stid(stid);
- if (new_id < 0)
- return nfserr_jukebox;
s->si_opaque.so_id = (u32)new_id;
/* Will be incremented before return to client: */
s->si_generation = 0;
- return 0;
+}
+
+static struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab)
+{
+ struct idr *stateids = &cl->cl_stateids;
+
+ if (!idr_pre_get(stateids, GFP_KERNEL))
+ return NULL;
+ /*
+ * Note: if we fail here (or any time between now and the time
+ * we actually get the new idr), we won't need to undo the idr
+ * preallocation, since the idr code caps the number of
+ * preallocated entries.
+ */
+ return kmem_cache_alloc(slab, GFP_KERNEL);
}
static struct nfs4_delegation *
@@ -262,7 +273,6 @@
{
struct nfs4_delegation *dp;
struct nfs4_file *fp = stp->st_file;
- __be32 status;
dprintk("NFSD alloc_init_deleg\n");
/*
@@ -276,14 +286,10 @@
return NULL;
if (num_delegations > max_delegations)
return NULL;
- dp = kmem_cache_alloc(deleg_slab, GFP_KERNEL);
+ dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
if (dp == NULL)
return dp;
- status = init_stid(&dp->dl_stid, clp, NFS4_DELEG_STID);
- if (status) {
- kmem_cache_free(deleg_slab, dp);
- return NULL;
- }
+ init_stid(&dp->dl_stid, clp, NFS4_DELEG_STID);
/*
* delegation seqid's are never incremented. The 4.1 special
* meaning of seqid 0 isn't meaningful, really, but let's avoid
@@ -2331,14 +2337,11 @@
return oo;
}
-static inline __be32 init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *open) {
+static void init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *open) {
struct nfs4_openowner *oo = open->op_openowner;
struct nfs4_client *clp = oo->oo_owner.so_client;
- __be32 status;
- status = init_stid(&stp->st_stid, clp, NFS4_OPEN_STID);
- if (status)
- return status;
+ init_stid(&stp->st_stid, clp, NFS4_OPEN_STID);
INIT_LIST_HEAD(&stp->st_lockowners);
list_add(&stp->st_perstateowner, &oo->oo_owner.so_stateids);
list_add(&stp->st_perfile, &fp->fi_stateids);
@@ -2350,7 +2353,6 @@
__set_bit(open->op_share_access, &stp->st_access_bmap);
__set_bit(open->op_share_deny, &stp->st_deny_bmap);
stp->st_openstp = NULL;
- return nfs_ok;
}
static void
@@ -2614,10 +2616,14 @@
return nfs_ok;
}
-static inline struct nfs4_ol_stateid *
-nfs4_alloc_stateid(void)
+static struct nfs4_ol_stateid * nfs4_alloc_stateid(struct nfs4_client *clp)
{
- return kmem_cache_alloc(stateid_slab, GFP_KERNEL);
+ return openlockstateid(nfs4_alloc_stid(clp, stateid_slab));
+}
+
+static void nfs4_free_stateid(struct nfs4_ol_stateid *s)
+{
+ kmem_cache_free(stateid_slab, s);
}
static inline int nfs4_access_to_access(u32 nfs4_access)
@@ -2661,15 +2667,16 @@
struct nfsd4_open *open)
{
struct nfs4_ol_stateid *stp;
+ struct nfs4_client *cl = open->op_openowner->oo_owner.so_client;
__be32 status;
- stp = nfs4_alloc_stateid();
+ stp = nfs4_alloc_stateid(cl);
if (stp == NULL)
return nfserr_jukebox;
status = nfs4_get_vfs_file(rqstp, fp, cur_fh, open);
if (status) {
- kmem_cache_free(stateid_slab, stp);
+ nfs4_free_stateid(stp);
return status;
}
*stpp = stp;
@@ -2912,11 +2919,7 @@
status = nfs4_new_open(rqstp, &stp, fp, current_fh, open);
if (status)
goto out;
- status = init_open_stateid(stp, fp, open);
- if (status) {
- release_open_stateid(stp);
- goto out;
- }
+ init_open_stateid(stp, fp, open);
status = nfsd4_truncate(rqstp, current_fh, open);
if (status) {
release_open_stateid(stp);
@@ -3812,16 +3815,11 @@
{
struct nfs4_ol_stateid *stp;
struct nfs4_client *clp = lo->lo_owner.so_client;
- __be32 status;
- stp = nfs4_alloc_stateid();
+ stp = nfs4_alloc_stateid(clp);
if (stp == NULL)
return NULL;
- status = init_stid(&stp->st_stid, clp, NFS4_LOCK_STID);
- if (status) {
- free_generic_stateid(stp);
- return NULL;
- }
+ init_stid(&stp->st_stid, clp, NFS4_LOCK_STID);
list_add(&stp->st_perfile, &fp->fi_stateids);
list_add(&stp->st_perstateowner, &lo->lo_owner.so_stateids);
stp->st_stateowner = &lo->lo_owner;