NFS: Add fs_context support.

Add filesystem context support to NFS, parsing the options in advance and
attaching the information to struct nfs_fs_context.  The highlights are:

 (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context.  This
     structure represents NFS's superblock config.

 (*) Make use of the VFS's parsing support to split comma-separated lists

 (*) Pin the NFS protocol module in the nfs_fs_context.

 (*) Attach supplementary error information to fs_context.  This has the
     downside that these strings must be static and can't be formatted.

 (*) Remove the auxiliary file_system_type structs since the information
     necessary can be conveyed in the nfs_fs_context struct instead.

 (*) Root mounts are made by duplicating the config for the requested mount
     so as to have the same parameters.  Submounts pick up their parameters
     from the parent superblock.

[AV -- retrans is u32, not string]
[SM -- Renamed cfg to ctx in a few functions in an earlier patch]
[SM -- Moved fs_context mount option parsing to an earlier patch]
[SM -- Moved fs_context error logging to a later patch]
[SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()]
[SM -- Added is_remount_fc() helper]
[SM -- Deferred some refactoring to a later patch]
[SM -- Fixed referral mounts, which were broken in the original patch]
[SM -- Fixed leak of nfs_fattr when fs_context is freed]

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
David Howells
2019-12-10 07:31:13 -05:00
committed by Anna Schumaker
parent e38bb238ed
commit f2aedb713c
12 changed files with 778 additions and 664 deletions

View File

@@ -268,14 +268,13 @@ extern const struct dentry_operations nfs4_dentry_operations;
int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
unsigned, umode_t);
/* super.c */
/* fs_context.c */
extern struct file_system_type nfs4_fs_type;
/* nfs4namespace.c */
struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
const struct qstr *);
struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
struct nfs_fh *, struct nfs_fattr *);
int nfs4_submount(struct fs_context *, struct nfs_server *);
int nfs4_replace_transport(struct nfs_server *server,
const struct nfs4_fs_locations *locations);
@@ -526,7 +525,6 @@ extern const nfs4_stateid invalid_stateid;
/* nfs4super.c */
struct nfs_mount_info;
extern struct nfs_subversion nfs_v4;
struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *);
extern bool nfs4_disable_idmapping;
extern unsigned short max_session_slots;
extern unsigned short max_session_cb_slots;
@@ -536,6 +534,9 @@ extern bool recover_lost_locks;
#define NFS4_CLIENT_ID_UNIQ_LEN (64)
extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
extern int nfs4_try_get_tree(struct fs_context *);
extern int nfs4_get_referral_tree(struct fs_context *);
/* nfs4sysctl.c */
#ifdef CONFIG_SYSCTL
int nfs4_register_sysctl(void);