Create a sysfs directory for each mount that corresponds to the mount's
nfs_server struct. As the mount is being constructed, use the name
"server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning
a device_id. The rename approach allows us to populate the mount's directory
with links to the various rpc_client objects during the mount's
construction. The naming convention (MAJOR:MINOR) can be used to reference
a particular NFS mount's sysfs tree.
Signed-off-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
---
fs/nfs/client.c | 15 +++++++++++
fs/nfs/super.c | 6 ++++-
fs/nfs/sysfs.c | 54 +++++++++++++++++++++++++++++++++++++++
fs/nfs/sysfs.h | 5 ++++
include/linux/nfs_fs_sb.h | 2 ++
5 files changed, 81 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index f50e025ae406..72da715fc617 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -944,6 +944,8 @@ void nfs_server_remove_lists(struct nfs_server *server)
}
EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
+static DEFINE_IDA(s_sysfs_ids);
+
/*
* Allocate and initialise a server record
*/
@@ -955,6 +957,13 @@ struct nfs_server *nfs_alloc_server(void)
if (!server)
return NULL;
+ server->s_sysfs_id = ida_simple_get(
+ &s_sysfs_ids, 0, 0, GFP_KERNEL);
+ if (server->s_sysfs_id < 0) {
+ kfree(server);
+ return NULL;
+ }
+
server->client = server->client_acl = ERR_PTR(-EINVAL);
/* Zero out the NFS state stuff */
@@ -979,6 +988,7 @@ struct nfs_server *nfs_alloc_server(void)
ida_init(&server->lockowner_id);
pnfs_init_server(server);
rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
+ nfs_sysfs_add_server(server);
return server;
}
@@ -1001,6 +1011,10 @@ void nfs_free_server(struct nfs_server *server)
nfs_put_client(server->nfs_client);
+ nfs_sysfs_remove_server(server);
+ kobject_put(&server->kobj);
+ ida_simple_remove(&s_sysfs_ids, server->s_sysfs_id);
+
ida_destroy(&server->lockowner_id);
ida_destroy(&server->openowner_id);
nfs_free_iostats(server->io_stats);
@@ -1385,6 +1399,7 @@ int __init nfs_fs_proc_init(void)
void nfs_fs_proc_exit(void)
{
remove_proc_subtree("fs/nfsfs", NULL);
+ ida_destroy(&s_sysfs_ids);
}
#endif /* CONFIG_PROC_FS */
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 05ae23657527..40a866db7965 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -68,6 +68,8 @@
#include "nfs4session.h"
#include "pnfs.h"
#include "nfs.h"
+#include "netns.h"
+#include "sysfs.h"
#define NFSDBG_FACILITY NFSDBG_VFS
@@ -1088,6 +1090,7 @@ static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx)
&sb->s_blocksize_bits);
nfs_super_set_maxbytes(sb, server->maxfilesize);
+ nfs_sysfs_move_server_to_sb(sb);
server->has_sec_mnt_opts = ctx->has_sec_mnt_opts;
}
@@ -1333,13 +1336,14 @@ int nfs_get_tree_common(struct fs_context *fc)
}
/*
- * Destroy an NFS2/3 superblock
+ * Destroy an NFS superblock
*/
void nfs_kill_super(struct super_block *s)
{
struct nfs_server *server = NFS_SB(s);
dev_t dev = s->s_dev;
+ nfs_sysfs_move_sb_to_server(server);
generic_shutdown_super(s);
nfs_fscache_release_super_cookie(s);
diff --git a/fs/nfs/sysfs.c b/fs/nfs/sysfs.c
index a496e26fcfb7..9eb9fbbf606e 100644
--- a/fs/nfs/sysfs.c
+++ b/fs/nfs/sysfs.c
@@ -190,3 +190,57 @@ void nfs_netns_sysfs_destroy(struct nfs_net *netns)
netns->nfs_client = NULL;
}
}
+
+static void nfs_sysfs_sb_release(struct kobject *kobj)
+{
+ /* no-op: why? see lib/kobject.c kobject_cleanup() */
+}
+
+static struct attribute *nfs_mp_attrs[] = {
+ NULL,
+};
+
+ATTRIBUTE_GROUPS(nfs_mp);
+
+static struct kobj_type nfs_sb_ktype = {
+ .release = nfs_sysfs_sb_release,
+ .sysfs_ops = &kobj_sysfs_ops,
+ .default_groups = nfs_mp_groups,
+};
+
+void nfs_sysfs_add_server(struct nfs_server *server)
+{
+ int ret;
+ ret = kobject_init_and_add(&server->kobj, &nfs_sb_ktype,
+ &nfs_kset->kobj, "server-%d", server->s_sysfs_id);
+}
+
+void nfs_sysfs_move_server_to_sb(struct super_block *s)
+{
+ struct nfs_server *server = s->s_fs_info;
+ int ret;
+
+ ret = kobject_rename(&server->kobj, s->s_id);
+ if (ret < 0)
+ pr_warn("NFS: rename sysfs %s failed (%d)\n",
+ server->kobj.name, ret);
+}
+
+void nfs_sysfs_move_sb_to_server(struct nfs_server *server)
+{
+ const char *s;
+ int ret = -ENOMEM;
+
+ s = kasprintf(GFP_KERNEL, "server-%d", server->s_sysfs_id);
+ if (s)
+ ret = kobject_rename(&server->kobj, s);
+ if (ret < 0)
+ pr_warn("NFS: rename sysfs %s failed (%d)\n",
+ server->kobj.name, ret);
+}
+
+/* unlink, not dec-ref */
+void nfs_sysfs_remove_server(struct nfs_server *server)
+{
+ kobject_del(&server->kobj);
+}
diff --git a/fs/nfs/sysfs.h b/fs/nfs/sysfs.h
index 5501ef573c32..ca2373fc76cf 100644
--- a/fs/nfs/sysfs.h
+++ b/fs/nfs/sysfs.h
@@ -22,4 +22,9 @@ extern void nfs_sysfs_exit(void);
void nfs_netns_sysfs_setup(struct nfs_net *netns, struct net *net);
void nfs_netns_sysfs_destroy(struct nfs_net *netns);
+void nfs_sysfs_add_server(struct nfs_server *s);
+void nfs_sysfs_move_server_to_sb(struct super_block *s);
+void nfs_sysfs_move_sb_to_server(struct nfs_server *s);
+void nfs_sysfs_remove_server(struct nfs_server *s);
+
#endif
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index ea2f7e6b1b0b..dee1664abca8 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -183,6 +183,7 @@ struct nfs_server {
change_attr_type;/* Description of change attribute */
struct nfs_fsid fsid;
+ int s_sysfs_id; /* sysfs dentry index */
__u64 maxfilesize; /* maximum file size */
struct timespec64 time_delta; /* smallest time granularity */
unsigned long mount_time; /* when this fs was mounted */
@@ -259,6 +260,7 @@ struct nfs_server {
/* User namespace info */
const struct cred *cred;
bool has_sec_mnt_opts;
+ struct kobject kobj;
};
/* Server capabilities */
--
2.39.2
