[PATCH 23/38] vfs: Kill sget_userns()

From: David Howells
Date: Thu Mar 14 2019 - 12:12:03 EST


Kill sget_userns(), folding it into sget() as that's the only remaining
user.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: linux-fsdevel@xxxxxxxxxxxxxxx
---

fs/super.c | 61 +++++++++++++++++-----------------------------------
include/linux/fs.h | 5 ----
2 files changed, 20 insertions(+), 46 deletions(-)

diff --git a/fs/super.c b/fs/super.c
index 3b5275298f7c..f27ee08fb26f 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -566,24 +566,35 @@ struct super_block *sget_fc(struct fs_context *fc,
EXPORT_SYMBOL(sget_fc);

/**
- * sget_userns - find or create a superblock
- * @type: filesystem type superblock should belong to
- * @test: comparison callback
- * @set: setup callback
- * @flags: mount flags
- * @user_ns: User namespace for the super_block
- * @data: argument to each of them
+ * sget - find or create a superblock
+ * @type: filesystem type superblock should belong to
+ * @test: comparison callback
+ * @set: setup callback
+ * @flags: mount flags
+ * @data: argument to each of them
*/
-struct super_block *sget_userns(struct file_system_type *type,
+struct super_block *sget(struct file_system_type *type,
int (*test)(struct super_block *,void *),
int (*set)(struct super_block *,void *),
- int flags, struct user_namespace *user_ns,
+ int flags,
void *data)
{
+ struct user_namespace *user_ns = current_user_ns();
struct super_block *s = NULL;
struct super_block *old;
int err;

+ /* We don't yet pass the user namespace of the parent
+ * mount through to here so always use &init_user_ns
+ * until that changes.
+ */
+ if (flags & SB_SUBMOUNT)
+ user_ns = &init_user_ns;
+
+ /* Ensure the requestor has permissions over the target filesystem */
+ if (!(flags & (SB_KERNMOUNT|SB_SUBMOUNT)) && !ns_capable(user_ns, CAP_SYS_ADMIN))
+ return ERR_PTR(-EPERM);
+
if (!(flags & (SB_KERNMOUNT|SB_SUBMOUNT)) &&
!(type->fs_flags & FS_USERNS_MOUNT) &&
!capable(CAP_SYS_ADMIN))
@@ -629,38 +640,6 @@ struct super_block *sget_userns(struct file_system_type *type,
return s;
}

-EXPORT_SYMBOL(sget_userns);
-
-/**
- * sget - find or create a superblock
- * @type: filesystem type superblock should belong to
- * @test: comparison callback
- * @set: setup callback
- * @flags: mount flags
- * @data: argument to each of them
- */
-struct super_block *sget(struct file_system_type *type,
- int (*test)(struct super_block *,void *),
- int (*set)(struct super_block *,void *),
- int flags,
- void *data)
-{
- struct user_namespace *user_ns = current_user_ns();
-
- /* We don't yet pass the user namespace of the parent
- * mount through to here so always use &init_user_ns
- * until that changes.
- */
- if (flags & SB_SUBMOUNT)
- user_ns = &init_user_ns;
-
- /* Ensure the requestor has permissions over the target filesystem */
- if (!(flags & (SB_KERNMOUNT|SB_SUBMOUNT)) && !ns_capable(user_ns, CAP_SYS_ADMIN))
- return ERR_PTR(-EPERM);
-
- return sget_userns(type, test, set, flags, user_ns, data);
-}
-
EXPORT_SYMBOL(sget);

void drop_super(struct super_block *sb)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 20c15794c2ac..646f4ccaeee9 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2233,11 +2233,6 @@ void free_anon_bdev(dev_t);
struct super_block *sget_fc(struct fs_context *fc,
int (*test)(struct super_block *, struct fs_context *),
int (*set)(struct super_block *, struct fs_context *));
-struct super_block *sget_userns(struct file_system_type *type,
- int (*test)(struct super_block *,void *),
- int (*set)(struct super_block *,void *),
- int flags, struct user_namespace *user_ns,
- void *data);
struct super_block *sget(struct file_system_type *type,
int (*test)(struct super_block *,void *),
int (*set)(struct super_block *,void *),