afs: Use fs_context to pass parameters over automount

Alter the AFS automounting code to create and modify an fs_context struct
when parameterising a new mount triggered by an AFS mountpoint rather than
constructing device name and option strings.

Also remove the cell=, vol= and rwpath options as they are then redundant.
The reason they existed is because the 'device name' may be derived
literally from a mountpoint object in the filesystem, so default cell and
parent-type information needed to be passed in by some other method from
the automount routines.  The vol= option didn't end up being used.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric W. Biederman <ebiederm@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 3 insertions, 37 deletions

diff --git a/fs/afs/super.c b/fs/afs/super.c
index e1a7a8085262..a07af1ab488d 100644
--- a/fs/afs/super.c
+++ b/fs/afs/super.c
@@ -66,20 +66,14 @@ static atomic_t afs_count_active_inodes;
 
 enum afs_param {
 	Opt_autocell,
-	Opt_cell,
 	Opt_dyn,
-	Opt_rwpath,
 	Opt_source,
-	Opt_vol,
 };
 
 static const struct fs_parameter_spec afs_param_specs[] = {
 	fsparam_flag  ("autocell",	Opt_autocell),
-	fsparam_string("cell",		Opt_cell),
 	fsparam_flag  ("dyn",		Opt_dyn),
-	fsparam_flag  ("rwpath",	Opt_rwpath),
 	fsparam_string("source",	Opt_source),
-	fsparam_string("vol",		Opt_vol),
 	{}
 };
 
@@ -202,8 +196,8 @@ static int afs_show_options(struct seq_file *m, struct dentry *root)
  *
  * This can be one of the following:
  *	"%[cell:]volume[.]"		R/W volume
- *	"#[cell:]volume[.]"		R/O or R/W volume (rwpath=0),
- *					 or R/W (rwpath=1) volume
+ *	"#[cell:]volume[.]"		R/O or R/W volume (R/O parent),
+ *					 or R/W (R/W parent) volume
  *	"%[cell:]volume.readonly"	R/O volume
  *	"#[cell:]volume.readonly"	R/O volume
  *	"%[cell:]volume.backup"		Backup volume
@@ -234,9 +228,7 @@ static int afs_parse_source(struct fs_context *fc, struct fs_parameter *param)
 	}
 
 	/* determine the type of volume we're looking for */
-	ctx->type = AFSVL_ROVOL;
-	ctx->force = false;
-	if (ctx->rwpath || name[0] == '%') {
+	if (name[0] == '%') {
 		ctx->type = AFSVL_RWVOL;
 		ctx->force = true;
 	}
@@ -305,7 +297,6 @@ static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 {
 	struct fs_parse_result result;
 	struct afs_fs_context *ctx = fc->fs_private;
-	struct afs_cell *cell;
 	int opt;
 
 	opt = fs_parse(fc, &afs_fs_parameters, param, &result);
@@ -313,21 +304,6 @@ static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 		return opt;
 
 	switch (opt) {
-	case Opt_cell:
-		if (param->size <= 0)
-			return -EINVAL;
-		if (param->size > AFS_MAXCELLNAME)
-			return -ENAMETOOLONG;
-
-		rcu_read_lock();
-		cell = afs_lookup_cell_rcu(ctx->net, param->string, param->size);
-		rcu_read_unlock();
-		if (IS_ERR(cell))
-			return PTR_ERR(cell);
-		afs_put_cell(ctx->net, ctx->cell);
-		ctx->cell = cell;
-		break;
-
 	case Opt_source:
 		return afs_parse_source(fc, param);
 
@@ -339,13 +315,6 @@ static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 		ctx->dyn_root = true;
 		break;
 
-	case Opt_rwpath:
-		ctx->rwpath = true;
-		break;
-
-	case Opt_vol:
-		return invalf(fc, "'vol' param is obsolete");
-
 	default:
 		return -EINVAL;
 	}
@@ -616,9 +585,6 @@ static int afs_init_fs_context(struct fs_context *fc)
 	struct afs_fs_context *ctx;
 	struct afs_cell *cell;
 
-	if (current->nsproxy->net_ns != &init_net)
-		return -EINVAL;
-
 	ctx = kzalloc(sizeof(struct afs_fs_context), GFP_KERNEL);
 	if (!ctx)
 		return -ENOMEM;