2013-09-05 15:14:58

by Andy Adamson

[permalink] [raw]
Subject: [PATCH 1/1] NFSv4.1 Use MDS auth flavor for data server connection

From: Andy Adamson <[email protected]>

Commit 4edaa308 "NFS: Use "krb5i" to establish NFSv4 state whenever possible"
uses the nfs_client cl_rpcclient for all state management operations, and
will use krb5i or auth_sys with no regard to the mount command authflavor
choice.

The MDS, as any NFSv4.1 mount point, uses the nfs_server rpc client for all
non-state management operations with a different nfs_server for each fsid
encountered traversing the mount point, each with a potentially different
auth flavor.

pNFS data servers are not mounted in the normal sense as there is no associated
nfs_server structure. Data servers can also export multiple fsids, each with
a potentially different auth flavor.

Data servers need to use the same authflavor as the MDS server rpc client for
non-state management operations. Populate a list of rpc clients with the MDS
server rpc client auth flavor for the DS to use.

Signed-off-by: Andy Adamson <[email protected]>
---
fs/nfs/internal.h | 2 ++
fs/nfs/nfs4client.c | 75 +++++++++++++++++++++++++++++++++++++++++++++
fs/nfs/nfs4filelayout.c | 35 ++++++++++++++++-----
include/linux/nfs_fs_sb.h | 1 +
include/linux/sunrpc/clnt.h | 2 ++
net/sunrpc/clnt.c | 1 +
6 files changed, 108 insertions(+), 8 deletions(-)

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 2415198..23ec6e8 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -186,6 +186,8 @@ extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
int ds_addrlen, int ds_proto,
unsigned int ds_timeo,
unsigned int ds_retrans);
+extern struct rpc_clnt *nfs4_find_or_create_ds_client(struct nfs_client *,
+ struct inode *);
#ifdef CONFIG_PROC_FS
extern int __init nfs_fs_proc_init(void);
extern void nfs_fs_proc_exit(void);
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 767a5e3..afea8f0 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -49,10 +49,83 @@ static void nfs4_shutdown_session(struct nfs_client *clp)
}

}
+
+static struct rpc_clnt *
+nfs4_find_or_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
+ struct rpc_clnt *new)
+{
+ struct rpc_clnt *ds_clnt, *tmp;
+
+ spin_lock(&ds_clp->cl_lock);
+ list_for_each_entry_safe(ds_clnt, tmp, &ds_clp->cl_ds_clients,
+ cl_ds_clnts) {
+ if (ds_clnt->cl_auth->au_flavor != flavor)
+ continue;
+ goto out;
+ }
+ if (new)
+ list_add(&new->cl_ds_clnts, &ds_clp->cl_ds_clients);
+ ds_clnt = new;
+out:
+ spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
+ return ds_clnt;
+}
+
+/**
+ * Find or create a DS rpc client with th MDS server rpc client auth flavor
+ * in the nfs_client cl_ds_clients list.
+ */
+struct rpc_clnt *
+nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
+{
+ struct rpc_clnt *ds_rpc_client, *new;
+ rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
+
+ ds_rpc_client = nfs4_find_or_add_ds_client(ds_clp, flavor, NULL);
+ if (ds_rpc_client != NULL)
+ goto out;
+ new = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
+ if (IS_ERR(new))
+ return new;
+ ds_rpc_client = nfs4_find_or_add_ds_client(ds_clp, flavor, new);
+ if (ds_rpc_client != new)
+ rpc_release_client(new);
+out:
+ return ds_rpc_client;
+}
+EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
+
+static void
+nfs4_shutdown_ds_clients(struct nfs_client *clp)
+{
+ struct rpc_clnt *clnt;
+ LIST_HEAD(shutdown_list);
+
+ spin_lock(&clp->cl_lock);
+ while (!list_empty(&clp->cl_ds_clients)) {
+ clnt = list_entry(clp->cl_ds_clients.next,
+ struct rpc_clnt, cl_ds_clnts);
+ list_move(&clnt->cl_ds_clnts, &shutdown_list);
+ }
+ spin_unlock(&clp->cl_lock);
+
+ while (!list_empty(&shutdown_list)) {
+ clnt = list_entry(shutdown_list.next,
+ struct rpc_clnt, cl_ds_clnts);
+ list_del(&clnt->cl_ds_clnts);
+ rpc_shutdown_client(clnt);
+ }
+}
+
#else /* CONFIG_NFS_V4_1 */
static void nfs4_shutdown_session(struct nfs_client *clp)
{
}
+
+static void
+nfs4_shutdown_ds_clients(struct nfs_client *clp)
+{
+}
#endif /* CONFIG_NFS_V4_1 */

struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
@@ -73,6 +146,7 @@ struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)

spin_lock_init(&clp->cl_lock);
INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
+ INIT_LIST_HEAD(&clp->cl_ds_clients);
rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
clp->cl_minorversion = cl_init->minorversion;
@@ -97,6 +171,7 @@ static void nfs4_shutdown_client(struct nfs_client *clp)
{
if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
nfs4_kill_renewd(clp);
+ nfs4_shutdown_ds_clients(clp);
nfs4_shutdown_session(clp);
nfs4_destroy_callback(clp);
if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index a70cb3a..b86464b 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -528,6 +528,7 @@ filelayout_read_pagelist(struct nfs_read_data *data)
struct nfs_pgio_header *hdr = data->header;
struct pnfs_layout_segment *lseg = hdr->lseg;
struct nfs4_pnfs_ds *ds;
+ struct rpc_clnt *ds_clnt;
loff_t offset = data->args.offset;
u32 j, idx;
struct nfs_fh *fh;
@@ -542,6 +543,11 @@ filelayout_read_pagelist(struct nfs_read_data *data)
ds = nfs4_fl_prepare_ds(lseg, idx);
if (!ds)
return PNFS_NOT_ATTEMPTED;
+
+ ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
+ if (IS_ERR(ds_clnt))
+ return PNFS_NOT_ATTEMPTED;
+
dprintk("%s USE DS: %s cl_count %d\n", __func__,
ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));

@@ -556,7 +562,7 @@ filelayout_read_pagelist(struct nfs_read_data *data)
data->mds_offset = offset;

/* Perform an asynchronous read to ds */
- nfs_initiate_read(ds->ds_clp->cl_rpcclient, data,
+ nfs_initiate_read(ds_clnt, data,
&filelayout_read_call_ops, RPC_TASK_SOFTCONN);
return PNFS_ATTEMPTED;
}
@@ -568,6 +574,7 @@ filelayout_write_pagelist(struct nfs_write_data *data, int sync)
struct nfs_pgio_header *hdr = data->header;
struct pnfs_layout_segment *lseg = hdr->lseg;
struct nfs4_pnfs_ds *ds;
+ struct rpc_clnt *ds_clnt;
loff_t offset = data->args.offset;
u32 j, idx;
struct nfs_fh *fh;
@@ -578,6 +585,11 @@ filelayout_write_pagelist(struct nfs_write_data *data, int sync)
ds = nfs4_fl_prepare_ds(lseg, idx);
if (!ds)
return PNFS_NOT_ATTEMPTED;
+
+ ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
+ if (IS_ERR(ds_clnt))
+ return PNFS_NOT_ATTEMPTED;
+
dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d\n",
__func__, hdr->inode->i_ino, sync, (size_t) data->args.count,
offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
@@ -595,7 +607,7 @@ filelayout_write_pagelist(struct nfs_write_data *data, int sync)
data->args.offset = filelayout_get_dserver_offset(lseg, offset);

/* Perform an asynchronous write */
- nfs_initiate_write(ds->ds_clp->cl_rpcclient, data,
+ nfs_initiate_write(ds_clnt, data,
&filelayout_write_call_ops, sync,
RPC_TASK_SOFTCONN);
return PNFS_ATTEMPTED;
@@ -1105,16 +1117,19 @@ static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
{
struct pnfs_layout_segment *lseg = data->lseg;
struct nfs4_pnfs_ds *ds;
+ struct rpc_clnt *ds_clnt;
u32 idx;
struct nfs_fh *fh;

idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
ds = nfs4_fl_prepare_ds(lseg, idx);
- if (!ds) {
- prepare_to_resend_writes(data);
- filelayout_commit_release(data);
- return -EAGAIN;
- }
+ if (!ds)
+ goto out_err;
+
+ ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, data->inode);
+ if (IS_ERR(ds_clnt))
+ goto out_err;
+
dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count));
data->commit_done_cb = filelayout_commit_done_cb;
@@ -1123,9 +1138,13 @@ static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
if (fh)
data->args.fh = fh;
- return nfs_initiate_commit(ds->ds_clp->cl_rpcclient, data,
+ return nfs_initiate_commit(ds_clnt, data,
&filelayout_commit_call_ops, how,
RPC_TASK_SOFTCONN);
+out_err:
+ prepare_to_resend_writes(data);
+ filelayout_commit_release(data);
+ return -EAGAIN;
}

static int
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index d221243..4d476e7 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -56,6 +56,7 @@ struct nfs_client {
struct rpc_cred *cl_machine_cred;

#if IS_ENABLED(CONFIG_NFS_V4)
+ struct list_head cl_ds_clients; /* auth flavor data servers */
u64 cl_clientid; /* constant */
nfs4_verifier cl_confirm; /* Clientid verifier */
unsigned long cl_state;
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 76c0bf6..3919f2b 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -35,6 +35,8 @@ struct rpc_clnt {
atomic_t cl_count; /* Number of references */
struct list_head cl_clients; /* Global list of clients */
struct list_head cl_tasks; /* List of tasks */
+ struct list_head cl_ds_clnts; /* list of per auth flavor
+ data servers */
spinlock_t cl_lock; /* spinlock */
struct rpc_xprt __rcu * cl_xprt; /* transport */
struct rpc_procinfo * cl_procinfo; /* procedure info */
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index baf0df6..3c18394 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -356,6 +356,7 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
goto out_no_stats;
clnt->cl_program = program;
INIT_LIST_HEAD(&clnt->cl_tasks);
+ INIT_LIST_HEAD(&clnt->cl_ds_clnts);
spin_lock_init(&clnt->cl_lock);

if (!xprt_bound(xprt))
--
1.8.3.1



2013-09-05 15:31:37

by Myklebust, Trond

[permalink] [raw]
Subject: Re: [PATCH 1/1] NFSv4.1 Use MDS auth flavor for data server connection

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2013-09-05 15:44:30

by Andy Adamson

[permalink] [raw]
Subject: Re: [PATCH 1/1] NFSv4.1 Use MDS auth flavor for data server connection

On Thu, Sep 5, 2013 at 11:31 AM, Myklebust, Trond
<[email protected]> wrote:
> On Thu, 2013-09-05 at 11:14 -0400, [email protected] wrote:
>> From: Andy Adamson <[email protected]>
>>
>> Commit 4edaa308 "NFS: Use "krb5i" to establish NFSv4 state whenever possible"
>> uses the nfs_client cl_rpcclient for all state management operations, and
>> will use krb5i or auth_sys with no regard to the mount command authflavor
>> choice.
>>
>> The MDS, as any NFSv4.1 mount point, uses the nfs_server rpc client for all
>> non-state management operations with a different nfs_server for each fsid
>> encountered traversing the mount point, each with a potentially different
>> auth flavor.
>>
>> pNFS data servers are not mounted in the normal sense as there is no associated
>> nfs_server structure. Data servers can also export multiple fsids, each with
>> a potentially different auth flavor.
>>
>> Data servers need to use the same authflavor as the MDS server rpc client for
>> non-state management operations. Populate a list of rpc clients with the MDS
>> server rpc client auth flavor for the DS to use.
>>
>> Signed-off-by: Andy Adamson <[email protected]>
>> ---
>> fs/nfs/internal.h | 2 ++
>> fs/nfs/nfs4client.c | 75 +++++++++++++++++++++++++++++++++++++++++++++
>> fs/nfs/nfs4filelayout.c | 35 ++++++++++++++++-----
>> include/linux/nfs_fs_sb.h | 1 +
>> include/linux/sunrpc/clnt.h | 2 ++
>> net/sunrpc/clnt.c | 1 +
>> 6 files changed, 108 insertions(+), 8 deletions(-)
>>
> <snip>
>> diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
>> index 76c0bf6..3919f2b 100644
>> --- a/include/linux/sunrpc/clnt.h
>> +++ b/include/linux/sunrpc/clnt.h
>> @@ -35,6 +35,8 @@ struct rpc_clnt {
>> atomic_t cl_count; /* Number of references */
>> struct list_head cl_clients; /* Global list of clients */
>> struct list_head cl_tasks; /* List of tasks */
>> + struct list_head cl_ds_clnts; /* list of per auth flavor
>> + data servers */
>
> This list doesn't belong in the RPC layer. Please make a separate
> structure that lives in the NFS layer, and that owns the rpc_clnt.
>
> IOW something along the lines of:
>
> struct nfs_ds_server {
> struct list_head list; /* ds_clp->cl_ds_clients */
> struct rpc_clnt *rpc_clnt;
> };

OK

-->Andy
>
>> spinlock_t cl_lock; /* spinlock */
>> struct rpc_xprt __rcu * cl_xprt; /* transport */
>> struct rpc_procinfo * cl_procinfo; /* procedure info */
>> diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
>> index baf0df6..3c18394 100644
>> --- a/net/sunrpc/clnt.c
>> +++ b/net/sunrpc/clnt.c
>> @@ -356,6 +356,7 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
>> goto out_no_stats;
>> clnt->cl_program = program;
>> INIT_LIST_HEAD(&clnt->cl_tasks);
>> + INIT_LIST_HEAD(&clnt->cl_ds_clnts);
>> spin_lock_init(&clnt->cl_lock);
>>
>> if (!xprt_bound(xprt))
>
> --
> Trond Myklebust
> Linux NFS client maintainer
>
> NetApp
> [email protected]
> http://www.netapp.com