nfsd4: preallocate nfs4_file in process_open1()
Creating a new file is an irrevocable step--once it's visible in the
filesystem, other processes may have seen it and done something with it,
and unlinking it wouldn't simply undo the effects of the create.
Therefore, in the case where OPEN creates a new file, we shouldn't do
the create until we know that the rest of the OPEN processing will
succeed.
For example, we should preallocate a struct file in case we need it
until waiting to allocate it till process_open2(), which is already too
late.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 2c9a1a2..ae5d250 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -104,6 +104,11 @@
static struct list_head del_recall_lru;
+static void nfsd4_free_file(struct nfs4_file *f)
+{
+ kmem_cache_free(file_slab, f);
+}
+
static inline void
put_nfs4_file(struct nfs4_file *fi)
{
@@ -111,7 +116,7 @@
list_del(&fi->fi_hash);
spin_unlock(&recall_lock);
iput(fi->fi_inode);
- kmem_cache_free(file_slab, fi);
+ nfsd4_free_file(fi);
}
}
@@ -2190,30 +2195,28 @@
return status;
}
-/* OPEN Share state helper functions */
-static inline struct nfs4_file *
-alloc_init_file(struct inode *ino)
+static struct nfs4_file *nfsd4_alloc_file(void)
{
- struct nfs4_file *fp;
+ return kmem_cache_alloc(file_slab, GFP_KERNEL);
+}
+
+/* OPEN Share state helper functions */
+static void nfsd4_init_file(struct nfs4_file *fp, struct inode *ino)
+{
unsigned int hashval = file_hashval(ino);
- fp = kmem_cache_alloc(file_slab, GFP_KERNEL);
- if (fp) {
- atomic_set(&fp->fi_ref, 1);
- INIT_LIST_HEAD(&fp->fi_hash);
- INIT_LIST_HEAD(&fp->fi_stateids);
- INIT_LIST_HEAD(&fp->fi_delegations);
- fp->fi_inode = igrab(ino);
- fp->fi_had_conflict = false;
- fp->fi_lease = NULL;
- memset(fp->fi_fds, 0, sizeof(fp->fi_fds));
- memset(fp->fi_access, 0, sizeof(fp->fi_access));
- spin_lock(&recall_lock);
- list_add(&fp->fi_hash, &file_hashtbl[hashval]);
- spin_unlock(&recall_lock);
- return fp;
- }
- return NULL;
+ atomic_set(&fp->fi_ref, 1);
+ INIT_LIST_HEAD(&fp->fi_hash);
+ INIT_LIST_HEAD(&fp->fi_stateids);
+ INIT_LIST_HEAD(&fp->fi_delegations);
+ fp->fi_inode = igrab(ino);
+ fp->fi_had_conflict = false;
+ fp->fi_lease = NULL;
+ memset(fp->fi_fds, 0, sizeof(fp->fi_fds));
+ memset(fp->fi_access, 0, sizeof(fp->fi_access));
+ spin_lock(&recall_lock);
+ list_add(&fp->fi_hash, &file_hashtbl[hashval]);
+ spin_unlock(&recall_lock);
}
static void
@@ -2509,6 +2512,13 @@
if (STALE_CLIENTID(&open->op_clientid))
return nfserr_stale_clientid;
+ /*
+ * In case we need it later, after we've already created the
+ * file and don't want to risk a further failure:
+ */
+ open->op_file = nfsd4_alloc_file();
+ if (open->op_file == NULL)
+ return nfserr_jukebox;
strhashval = open_ownerstr_hashval(clientid->cl_id, &open->op_owner);
oo = find_openstateowner_str(strhashval, open);
@@ -2884,9 +2894,9 @@
if (open->op_claim_type == NFS4_OPEN_CLAIM_DELEGATE_CUR)
goto out;
status = nfserr_jukebox;
- fp = alloc_init_file(ino);
- if (fp == NULL)
- goto out;
+ fp = open->op_file;
+ open->op_file = NULL;
+ nfsd4_init_file(fp, ino);
}
/*
@@ -2960,6 +2970,8 @@
oo->oo_flags &= ~NFS4_OO_NEW;
}
}
+ if (open->op_file)
+ nfsd4_free_file(open->op_file);
}
__be32