NFS: Fix inheritance of the block sizes when automounting

Only inherit the block sizes that were actually specified as mount
parameters for the parent mount.

Fixes: 62a55d0 ("NFS: Additional refactoring for fs_context conversion")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Author: Trond Myklebust

fs/nfs/client.c

@@ -784,10 +784,18 @@ static int nfs_init_server(struct nfs_server *server,
 		server->fattr_valid = NFS_ATTR_FATTR_V4;
 	}
 
-	if (ctx->rsize)
+	if (ctx->bsize) {
+		server->bsize = ctx->bsize;
+		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_BSIZE;
+	}
+	if (ctx->rsize) {
 		server->rsize = nfs_io_size(ctx->rsize, clp->cl_proto);
-	if (ctx->wsize)
+		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_RSIZE;
+	}
+	if (ctx->wsize) {
 		server->wsize = nfs_io_size(ctx->wsize, clp->cl_proto);
+		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_WSIZE;
+	}
 
 	server->acregmin = ctx->acregmin * HZ;
 	server->acregmax = ctx->acregmax * HZ;
@@ -977,8 +985,13 @@ EXPORT_SYMBOL_GPL(nfs_probe_server);
 void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
 {
 	target->flags = source->flags;
-	target->rsize = source->rsize;
-	target->wsize = source->wsize;
+	target->automount_inherit = source->automount_inherit;
+	if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_BSIZE)
+		target->bsize = source->bsize;
+	if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_RSIZE)
+		target->rsize = source->rsize;
+	if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_WSIZE)
+		target->wsize = source->wsize;
 	target->acregmin = source->acregmin;
 	target->acregmax = source->acregmax;
 	target->acdirmin = source->acdirmin;

fs/nfs/internal.h

@@ -152,7 +152,6 @@ struct nfs_fs_context {
 		struct super_block	*sb;
 		struct dentry		*dentry;
 		struct nfs_fattr	*fattr;
-		unsigned int		inherited_bsize;
 	} clone_data;
 };
 

fs/nfs/namespace.c

@@ -190,6 +190,10 @@ struct vfsmount *nfs_d_automount(struct path *path)
 	ctx->nfs_mod		= client->cl_nfs_mod;
 	get_nfs_version(ctx->nfs_mod);
 
+	/* Inherit block sizes if they were specified as mount parameters */
+	if (server->automount_inherit & NFS_AUTOMOUNT_INHERIT_BSIZE)
+		ctx->bsize = server->bsize;
+
 	ret = client->rpc_ops->submount(fc, server);
 	if (ret < 0) {
 		mnt = ERR_PTR(ret);
@@ -289,7 +293,6 @@ int nfs_do_submount(struct fs_context *fc)
 		return -ENOMEM;
 
 	ctx->internal		= true;
-	ctx->clone_data.inherited_bsize = ctx->clone_data.sb->s_blocksize_bits;
 
 	p = nfs_devname(dentry, buffer, 4096);
 	if (IS_ERR(p)) {

fs/nfs/nfs4client.c

@@ -1179,10 +1179,20 @@ static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
 	if (error < 0)
 		return error;
 
-	if (ctx->rsize)
-		server->rsize = nfs_io_size(ctx->rsize, server->nfs_client->cl_proto);
-	if (ctx->wsize)
-		server->wsize = nfs_io_size(ctx->wsize, server->nfs_client->cl_proto);
+	if (ctx->bsize) {
+		server->bsize = ctx->bsize;
+		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_BSIZE;
+	}
+	if (ctx->rsize) {
+		server->rsize =
+			nfs_io_size(ctx->rsize, server->nfs_client->cl_proto);
+		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_RSIZE;
+	}
+	if (ctx->wsize) {
+		server->wsize =
+			nfs_io_size(ctx->wsize, server->nfs_client->cl_proto);
+		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_WSIZE;
+	}
 
 	server->acregmin = ctx->acregmin * HZ;
 	server->acregmax = ctx->acregmax * HZ;

fs/nfs/super.c

@@ -1091,8 +1091,9 @@ static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx)
 	sb->s_blocksize = 0;
 	sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
 	sb->s_op = server->nfs_client->cl_nfs_mod->sops;
-	if (ctx->bsize)
-		sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits);
+	if (server->bsize)
+		sb->s_blocksize =
+			nfs_block_size(server->bsize, &sb->s_blocksize_bits);
 
 	switch (server->nfs_client->rpc_ops->version) {
 	case 2:
@@ -1338,13 +1339,8 @@ int nfs_get_tree_common(struct fs_context *fc)
 	}
 
 	if (!s->s_root) {
-		unsigned bsize = ctx->clone_data.inherited_bsize;
 		/* initial superblock/root creation */
 		nfs_fill_super(s, ctx);
-		if (bsize) {
-			s->s_blocksize_bits = bsize;
-			s->s_blocksize = 1U << bsize;
-		}
 		error = nfs_get_cache_cookie(s, ctx);
 		if (error < 0)
 			goto error_splat_super;

include/linux/nfs_fs_sb.h

@@ -172,6 +172,11 @@ struct nfs_server {
 #define NFS_MOUNT_FORCE_RDIRPLUS	0x20000000
 #define NFS_MOUNT_NETUNREACH_FATAL	0x40000000
 
+	unsigned int		automount_inherit; /* Properties inherited by automount */
+#define NFS_AUTOMOUNT_INHERIT_BSIZE	0x0001
+#define NFS_AUTOMOUNT_INHERIT_RSIZE	0x0002
+#define NFS_AUTOMOUNT_INHERIT_WSIZE	0x0004
+
 	unsigned int		caps;		/* server capabilities */
 	__u64			fattr_valid;	/* Valid attributes */
 	unsigned int		rsize;		/* read size */