[PATCH] fs: use KERNEL_DS instead of get_ds()

[Jann Horn <jannh@google.com>]

get_ds() is a legacy name for KERNEL_DS; all architectures #define it to
KERNEL_DS, and almost every user of set_fs() uses the name KERNEL_DS.

Let the VFS also use KERNEL_DS so that we can get rid of get_ds() at some
point.

Signed-off-by: Jann Horn <jannh@google.com>
---
 fs/read_write.c | 6 +++---
 fs/splice.c     | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/read_write.c b/fs/read_write.c
index ff3c5e6f87cf..30df848b7451 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -426,7 +426,7 @@ ssize_t kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
 	ssize_t result;
 
 	old_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 	/* The cast to a user pointer is valid due to the set_fs() */
 	result = vfs_read(file, (void __user *)buf, count, pos);
 	set_fs(old_fs);
@@ -499,7 +499,7 @@ ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t
 		return -EINVAL;
 
 	old_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 	p = (__force const char __user *)buf;
 	if (count > MAX_RW_COUNT)
 		count =  MAX_RW_COUNT;
@@ -521,7 +521,7 @@ ssize_t kernel_write(struct file *file, const void *buf, size_t count,
 	ssize_t res;
 
 	old_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 	/* The cast to a user pointer is valid due to the set_fs() */
 	res = vfs_write(file, (__force const char __user *)buf, count, pos);
 	set_fs(old_fs);
diff --git a/fs/splice.c b/fs/splice.c
index de2ede048473..ec8b54b5c0d2 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -357,7 +357,7 @@ static ssize_t kernel_readv(struct file *file, const struct kvec *vec,
 	ssize_t res;
 
 	old_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 	/* The cast to a user pointer is valid due to the set_fs() */
 	res = vfs_readv(file, (const struct iovec __user *)vec, vlen, &pos, 0);
 	set_fs(old_fs);
-- 
2.21.0.352.gf09ad66450-goog