nfs: make nfs4_init_uniform_client_string use a dynamically allocated buffer
Change the uniform client string generator to dynamically allocate the
NFSv4 client name string buffer. With this patch, we can eliminate the
buffers that are embedded within the "args" structs and simply use the
name string that is hanging off the client.
This uniform string case is a little simpler than the nonuniform since
we don't need to deal with RCU, but we do have two different cases,
depending on whether there is a uniquifier or not.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index c203226..d181090 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5007,28 +5007,78 @@
return 0;
}
-static unsigned int
-nfs4_init_uniform_client_string(struct nfs_client *clp,
- char *buf, size_t len)
+static int
+nfs4_init_uniquifier_client_string(struct nfs_client *clp)
{
- const char *nodename = clp->cl_rpcclient->cl_nodename;
- unsigned int result;
+ int result;
+ size_t len;
+ char *str;
+
+ len = 10 + 10 + 1 + 10 + 1 +
+ strlen(nfs4_client_id_uniquifier) + 1 +
+ strlen(clp->cl_rpcclient->cl_nodename) + 1;
+
+ if (len > NFS4_OPAQUE_LIMIT + 1)
+ return -EINVAL;
+
+ /*
+ * Since this string is allocated at mount time, and held until the
+ * nfs_client is destroyed, we can use GFP_KERNEL here w/o worrying
+ * about a memory-reclaim deadlock.
+ */
+ str = kmalloc(len, GFP_KERNEL);
+ if (!str)
+ return -ENOMEM;
+
+ result = scnprintf(str, len, "Linux NFSv%u.%u %s/%s",
+ clp->rpc_ops->version, clp->cl_minorversion,
+ nfs4_client_id_uniquifier,
+ clp->cl_rpcclient->cl_nodename);
+ if (result >= len) {
+ kfree(str);
+ return -EINVAL;
+ }
+ clp->cl_owner_id = str;
+ return 0;
+}
+
+static int
+nfs4_init_uniform_client_string(struct nfs_client *clp)
+{
+ int result;
+ size_t len;
+ char *str;
if (clp->cl_owner_id != NULL)
- return strlcpy(buf, clp->cl_owner_id, len);
+ return 0;
if (nfs4_client_id_uniquifier[0] != '\0')
- result = scnprintf(buf, len, "Linux NFSv%u.%u %s/%s",
- clp->rpc_ops->version,
- clp->cl_minorversion,
- nfs4_client_id_uniquifier,
- nodename);
- else
- result = scnprintf(buf, len, "Linux NFSv%u.%u %s",
- clp->rpc_ops->version, clp->cl_minorversion,
- nodename);
- clp->cl_owner_id = kstrdup(buf, GFP_KERNEL);
- return result;
+ return nfs4_init_uniquifier_client_string(clp);
+
+ len = 10 + 10 + 1 + 10 + 1 +
+ strlen(clp->cl_rpcclient->cl_nodename) + 1;
+
+ if (len > NFS4_OPAQUE_LIMIT + 1)
+ return -EINVAL;
+
+ /*
+ * Since this string is allocated at mount time, and held until the
+ * nfs_client is destroyed, we can use GFP_KERNEL here w/o worrying
+ * about a memory-reclaim deadlock.
+ */
+ str = kmalloc(len, GFP_KERNEL);
+ if (!str)
+ return -ENOMEM;
+
+ result = scnprintf(str, len, "Linux NFSv%u.%u %s",
+ clp->rpc_ops->version, clp->cl_minorversion,
+ clp->cl_rpcclient->cl_nodename);
+ if (result >= len) {
+ kfree(str);
+ return -EINVAL;
+ }
+ clp->cl_owner_id = str;
+ return 0;
}
/*
@@ -5095,20 +5145,14 @@
/* nfs_client_id4 */
nfs4_init_boot_verifier(clp, &sc_verifier);
- if (test_bit(NFS_CS_MIGRATION, &clp->cl_flags)) {
- setclientid.sc_name_len =
- nfs4_init_uniform_client_string(clp,
- setclientid.sc_name,
- sizeof(setclientid.sc_name));
- if (!clp->cl_owner_id) {
- status = -ENOMEM;
- goto out;
- }
- } else {
+
+ if (test_bit(NFS_CS_MIGRATION, &clp->cl_flags))
+ status = nfs4_init_uniform_client_string(clp);
+ else
status = nfs4_init_nonuniform_client_string(clp);
- if (status)
- goto out;
- }
+
+ if (status)
+ goto out;
/* cb_client4 */
setclientid.sc_netid_len =
@@ -6882,12 +6926,10 @@
};
nfs4_init_boot_verifier(clp, &verifier);
- args.id_len = nfs4_init_uniform_client_string(clp, args.id,
- sizeof(args.id));
- if (!clp->cl_owner_id) {
- status = -ENOMEM;
+
+ status = nfs4_init_uniform_client_string(clp);
+ if (status)
goto out;
- }
dprintk("NFS call exchange_id auth=%s, '%s'\n",
clp->cl_rpcclient->cl_auth->au_ops->au_name,