From: Bryan Schumaker <bjschuma@xxxxxxxxxx>
This patch adds in the code to track multiple versions of the NFS
protocol. I created default structures for v2, v3 and v4 so that each
version can continue to work while I convert them into kernel modules.
Signed-off-by: Bryan Schumaker <bjschuma@xxxxxxxxxx>
---
fs/nfs/client.c | 148 +++++++++++++++++++++++++++++++++++++++++++++++-------
fs/nfs/inode.c | 2 +
fs/nfs/nfs.h | 73 +++++++++++++++++++++++++++
fs/nfs/super.c | 13 +++++
4 files changed, 216 insertions(+), 20 deletions(-)
create mode 100644 fs/nfs/nfs.h
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 01cb068..ee63d6a 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -49,10 +49,13 @@
#include "internal.h"
#include "fscache.h"
#include "pnfs.h"
+#include "nfs.h"
#define NFSDBG_FACILITY NFSDBG_CLIENT
static DEFINE_SPINLOCK(nfs_client_lock);
+static DEFINE_SPINLOCK(nfs_version_lock);
+static LIST_HEAD(nfs_versions);
static LIST_HEAD(nfs_client_list);
static LIST_HEAD(nfs_volume_list);
static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
@@ -90,15 +93,9 @@ static int nfs4_disable_idmapping = 0;
* RPC cruft for NFS
*/
static struct rpc_version *nfs_version[5] = {
-#ifdef CONFIG_NFS_V2
- [2] = &nfs_version2,
-#endif
-#ifdef CONFIG_NFS_V3
- [3] = &nfs_version3,
-#endif
-#ifdef CONFIG_NFS_V4
- [4] = &nfs_version4,
-#endif
+ [2] = NULL,
+ [3] = NULL,
+ [4] = NULL,
};
struct rpc_program nfs_program = {
@@ -114,6 +111,51 @@ struct rpc_stat nfs_rpcstat = {
.program = &nfs_program
};
+/*
+ * Default function for referencing and unreferencing
+ * nfs_version_module structures to prevent dereferencing
+ * a null pointer by the framework code. A functional
+ * version will be implemented by individual nfs versions
+ * as they are converted into modules.
+ *
+ * Once everything has been converted this function will
+ * be removed.
+ */
+#if defined(CONFIG_NFS_V2) || defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+static void nfs_module_null_function(void)
+{
+}
+#endif
+
+#ifdef CONFIG_NFS_V2
+static struct nfs_subversion nfs_v2_mod = {
+ .version = 2,
+ .rpc_vers = &nfs_version2,
+ .rpc_ops = &nfs_v2_clientops,
+ .reference = nfs_module_null_function,
+ .unreference = nfs_module_null_function,
+};
+#endif /* CONFIG_NFS_V2 */
+
+#ifdef CONFIG_NFS_V3
+static struct nfs_subversion nfs_v3_mod = {
+ .version = 3,
+ .rpc_vers = &nfs_version3,
+ .rpc_ops = &nfs_v3_clientops,
+ .reference = nfs_module_null_function,
+ .unreference = nfs_module_null_function,
+};
+#endif /* CONFIG_NFS_V3 */
+
+#ifdef CONFIG_NFS_V4
+static struct nfs_subversion nfs_v4_mod = {
+ .version = 4,
+ .rpc_vers = &nfs_version4,
+ .rpc_ops = &nfs_v4_clientops,
+ .reference = nfs_module_null_function,
+ .unreference = nfs_module_null_function,
+};
+#endif /* CONFIG_NFS_V4 */
#ifdef CONFIG_NFS_V3_ACL
static struct rpc_stat nfsacl_rpcstat = { &nfsacl_program };
@@ -139,6 +181,78 @@ struct nfs_client_initdata {
u32 minorversion;
};
+struct nfs_subversion *get_nfs_version(unsigned int version)
+{
+ struct nfs_subversion *nfs;
+
+ spin_lock(&nfs_version_lock);
+
+ list_for_each_entry(nfs, &nfs_versions, list) {
+ if (nfs->version == version) {
+ /* Keep track of the most recently used version */
+ list_move(&nfs->list, &nfs_versions);
+ goto out;
+ }
+ };
+
+ nfs = ERR_PTR(-EPROTONOSUPPORT);
+
+out:
+ spin_unlock(&nfs_version_lock);
+ return nfs;
+}
+
+inline struct nfs_subversion *get_nfs_client_version(struct nfs_client *clp)
+{
+ return get_nfs_version(clp->rpc_ops->version);
+}
+
+inline struct nfs_subversion *get_nfs_server_version(struct nfs_server *srv)
+{
+ return get_nfs_client_version(srv->nfs_client);
+}
+
+void register_nfs_version(struct nfs_subversion *nfs)
+{
+ spin_lock(&nfs_version_lock);
+
+ INIT_LIST_HEAD(&nfs->list);
+ list_add(&nfs->list, &nfs_versions);
+ nfs_version[nfs->version] = nfs->rpc_vers;
+
+ spin_unlock(&nfs_version_lock);
+}
+EXPORT_SYMBOL_GPL(register_nfs_version);
+
+void unregister_nfs_version(struct nfs_subversion *nfs)
+{
+ spin_lock(&nfs_version_lock);
+
+ nfs_version[nfs->version] = NULL;
+ list_del(&nfs->list);
+
+ spin_unlock(&nfs_version_lock);
+}
+EXPORT_SYMBOL_GPL(unregister_nfs_version);
+
+/*
+ * Preload all configured NFS versions during module init.
+ * This function should be edited after each protocol is converted,
+ * and eventually removed.
+ */
+void __init nfs_register_versions(void)
+{
+#ifdef CONFIG_NFS_V2
+ register_nfs_version(&nfs_v2_mod);
+#endif
+#ifdef CONFIG_NFS_V3
+ register_nfs_version(&nfs_v3_mod);
+#endif
+#ifdef CONFIG_NFS_V4
+ register_nfs_version(&nfs_v4_mod);
+#endif
+}
+
/*
* Allocate a shared client record
*
@@ -836,21 +950,15 @@ static int nfs_init_server(struct nfs_server *server,
};
struct rpc_timeout timeparms;
struct nfs_client *clp;
+ struct nfs_subversion *nfs_mod;
int error;
dprintk("--> nfs_init_server()\n");
-
-#ifdef CONFIG_NFS_V2
- if (data->version == 2)
- cl_init.rpc_ops = &nfs_v2_clientops;
-#endif
-#ifdef CONFIG_NFS_V3
- if (data->version == 3)
- cl_init.rpc_ops = &nfs_v3_clientops;
-#endif
- if (cl_init.rpc_ops == NULL)
- return -EPROTONOSUPPORT;
+ nfs_mod = get_nfs_version(data->version);
+ if (IS_ERR(nfs_mod))
+ return PTR_ERR(nfs_mod);
+ cl_init.rpc_ops = nfs_mod->rpc_ops;
nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
data->timeo, data->retrans);
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index f59cab1..3c81a32 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -50,6 +50,7 @@
#include "fscache.h"
#include "dns_resolve.h"
#include "pnfs.h"
+#include "nfs.h"
#define NFSDBG_FACILITY NFSDBG_VFS
@@ -1604,6 +1605,7 @@ static int __init init_nfs_fs(void)
#endif
if ((err = register_nfs_fs()) != 0)
goto out;
+ nfs_register_versions();
return 0;
out:
#ifdef CONFIG_PROC_FS
diff --git a/fs/nfs/nfs.h b/fs/nfs/nfs.h
new file mode 100644
index 0000000..b1fe653
--- /dev/null
+++ b/fs/nfs/nfs.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2012 Netapp, Inc. All rights reserved.
+ *
+ * Function and structures exported by the NFS module
+ * for use by NFS version-specific modules.
+ */
+#ifndef __LINUX_INTERNAL_NFS_H
+#define __LINUX_INTERNAL_NFS_H
+
+#include <linux/fs.h>
+#include <linux/sunrpc/sched.h>
+#include <linux/nfs_xdr.h>
+
+struct nfs_subversion {
+ unsigned int version; /* Protocol number */
+ struct rpc_version *rpc_vers; /* NFS version information */
+ const struct nfs_rpc_ops *rpc_ops; /* NFS operations */
+ struct list_head list; /* List of NFS versions */
+
+ void (*reference)(void); /* For reference counting */
+ void (*unreference)(void); /* Also for reference counting */
+};
+
+void nfs_register_versions(void);
+
+struct nfs_subversion *get_nfs_version(unsigned int);
+struct nfs_subversion *get_nfs_client_version(struct nfs_client *);
+struct nfs_subversion *get_nfs_server_version(struct nfs_server *);
+void register_nfs_version(struct nfs_subversion *);
+void unregister_nfs_version(struct nfs_subversion *);
+
+/* Exported in dir.c */
+int nfs_lookup_revalidate(struct dentry *, struct nameidata *);
+int nfs_dentry_delete(const struct dentry *);
+void nfs_dentry_iput(struct dentry *, struct inode *);
+void nfs_d_release(struct dentry *);
+struct dentry *nfs_lookup(struct inode *, struct dentry *, struct nameidata *);
+int nfs_create(struct inode *, struct dentry *, int, struct nameidata *);
+int nfs_mknod(struct inode *, struct dentry *, int, dev_t);
+int nfs_mkdir(struct inode *, struct dentry *, int);
+int nfs_rmdir(struct inode *, struct dentry *);
+int nfs_unlink(struct inode *, struct dentry *);
+int nfs_symlink(struct inode *, struct dentry *, const char *);
+int nfs_link(struct dentry *, struct inode *, struct dentry *);
+int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
+int nfs_permission(struct inode *, int);
+
+/* Exported in file.c */
+int nfs_check_flags(int);
+int nfs_file_open(struct inode *, struct file *);
+int nfs_file_release(struct inode *, struct file *);
+loff_t nfs_file_llseek(struct file *, loff_t, int);
+int nfs_file_flush(struct file *, fl_owner_t);
+ssize_t nfs_file_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
+ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
+ size_t, unsigned int);
+int nfs_file_mmap(struct file *, struct vm_area_struct *);
+int nfs_file_fsync(struct file *, loff_t, loff_t, int);
+ssize_t nfs_file_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
+ssize_t nfs_file_splice_write(struct pipe_inode_info *, struct file *,
+ loff_t *, size_t, unsigned int);
+int nfs_lock(struct file *, int, struct file_lock *);
+int nfs_flock(struct file *, int, struct file_lock *);
+int nfs_setlease(struct file *, long, struct file_lock **);
+
+/* Exported in inode.c */
+int nfs_setattr(struct dentry *, struct iattr *);
+int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
+
+/* Exported in namespace.c */
+struct vfsmount *nfs_d_automount(struct path *);
+
+#endif /* __LINUX_INTERNAL_NFS_H */
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 3ada13c..aee7b00 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -64,6 +64,7 @@
#include "internal.h"
#include "fscache.h"
#include "pnfs.h"
+#include "nfs.h"
#define NFSDBG_FACILITY NFSDBG_VFS
@@ -2229,6 +2230,7 @@ static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
struct nfs_sb_mountdata sb_mntdata = {
.mntflags = flags,
};
+ struct nfs_subversion *nfs_mod;
int error;
data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
@@ -2243,6 +2245,12 @@ static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
goto out;
}
+ nfs_mod = get_nfs_version(data->version);
+ if (IS_ERR(nfs_mod)) {
+ mntroot = (struct dentry *)nfs_mod;
+ goto out;
+ }
+
#ifdef CONFIG_NFS_V4
if (data->version == 4) {
mntroot = nfs4_try_mount(flags, dev_name, data);
@@ -2297,6 +2305,7 @@ static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
if (error)
goto error_splat_root;
+ nfs_mod->reference();
s->s_flags |= MS_ACTIVE;
out:
@@ -2326,6 +2335,10 @@ error_splat_bdi:
static void nfs_put_super(struct super_block *s)
{
struct nfs_server *server = NFS_SB(s);
+ struct nfs_subversion *nfs_mod = get_nfs_server_version(server);
+
+ if (!IS_ERR(nfs_mod))
+ nfs_mod->unreference();
bdi_unregister(&server->backing_dev_info);
}
--
1.7.8.3
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