powerpc/spufs: only add ".ctx" file with "debug" mount option

Currently, the .ctx debug file in spu context directories is always
present.

We'd prefer to prevent users from relying on this file, so add a
"debug" mount option to spufs. The .ctx file will only be added to
the context directories when this option is present.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

1 files changed, 33 insertions, 7 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c
index c662ca78360..7123472801d 100644
--- a/arch/powerpc/platforms/cell/spufs/inode.c
+++ b/arch/powerpc/platforms/cell/spufs/inode.c
@@ -42,10 +42,19 @@
 
 #include "spufs.h"
 
+struct spufs_sb_info {
+	int debug;
+};
+
 static struct kmem_cache *spufs_inode_cache;
 char *isolated_loader;
 static int isolated_loader_size;
 
+static struct spufs_sb_info *spufs_get_sb_info(struct super_block *sb)
+{
+	return sb->s_fs_info;
+}
+
 static struct inode *
 spufs_alloc_inode(struct super_block *sb)
 {
@@ -280,6 +289,13 @@ spufs_mkdir(struct inode *dir, struct dentry *dentry, unsigned int flags,
 	if (ret)
 		goto out_free_ctx;
 
+	if (spufs_get_sb_info(dir->i_sb)->debug)
+		ret = spufs_fill_dir(dentry, spufs_dir_debug_contents,
+				mode, ctx);
+
+	if (ret)
+		goto out_free_ctx;
+
 	d_instantiate(dentry, inode);
 	dget(dentry);
 	dir->i_nlink++;
@@ -640,18 +656,19 @@ out:
 
 /* File system initialization */
 enum {
-	Opt_uid, Opt_gid, Opt_mode, Opt_err,
+	Opt_uid, Opt_gid, Opt_mode, Opt_debug, Opt_err,
 };
 
 static match_table_t spufs_tokens = {
-	{ Opt_uid,  "uid=%d" },
-	{ Opt_gid,  "gid=%d" },
-	{ Opt_mode, "mode=%o" },
-	{ Opt_err,   NULL  },
+	{ Opt_uid,   "uid=%d" },
+	{ Opt_gid,   "gid=%d" },
+	{ Opt_mode,  "mode=%o" },
+	{ Opt_debug, "debug" },
+	{ Opt_err,    NULL  },
 };
 
 static int
-spufs_parse_options(char *options, struct inode *root)
+spufs_parse_options(struct super_block *sb, char *options, struct inode *root)
 {
 	char *p;
 	substring_t args[MAX_OPT_ARGS];
@@ -679,6 +696,9 @@ spufs_parse_options(char *options, struct inode *root)
 				return 0;
 			root->i_mode = option | S_IFDIR;
 			break;
+		case Opt_debug:
+			spufs_get_sb_info(sb)->debug = 1;
+			break;
 		default:
 			return 0;
 		}
@@ -737,7 +757,7 @@ spufs_create_root(struct super_block *sb, void *data)
 	SPUFS_I(inode)->i_ctx = NULL;
 
 	ret = -EINVAL;
-	if (!spufs_parse_options(data, inode))
+	if (!spufs_parse_options(sb, data, inode))
 		goto out_iput;
 
 	ret = -ENOMEM;
@@ -755,6 +775,7 @@ out:
 static int
 spufs_fill_super(struct super_block *sb, void *data, int silent)
 {
+	struct spufs_sb_info *info;
 	static struct super_operations s_ops = {
 		.alloc_inode = spufs_alloc_inode,
 		.destroy_inode = spufs_destroy_inode,
@@ -766,11 +787,16 @@ spufs_fill_super(struct super_block *sb, void *data, int silent)
 
 	save_mount_options(sb, data);
 
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
 	sb->s_blocksize = PAGE_CACHE_SIZE;
 	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 	sb->s_magic = SPUFS_MAGIC;
 	sb->s_op = &s_ops;
+	sb->s_fs_info = info;
 
 	return spufs_create_root(sb, data);
 }