ARM: 9480/1: entry: expand comment in __switch_tografted

As per discussion between the developers in the mail thread
linked, expand the comment in __switch_to so that readers
of the code understand what is going on.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Linus Walleij <linusw@kernel.org>>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

1 files changed, 25 insertions, 0 deletions

diff --git a/arch/mips/mm/pgtable.c b/arch/mips/mm/pgtable.c
new file mode 100644
index 000000000..108354148
--- /dev/null
+++ b/arch/mips/mm/pgtable.c
@@ -0,0 +1,25 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <asm/pgalloc.h>
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+	pgd_t *init, *ret;
+
+	ret = __pgd_alloc(mm, PGD_TABLE_ORDER);
+	if (ret) {
+		init = pgd_offset(&init_mm, 0UL);
+		pgd_init(ret);
+		memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
+		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pgd_alloc);