1 files changed, 79 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
new file mode 100644
index 000000000000..eab4779f6b84
--- /dev/null
+++ b/arch/powerpc/include/asm/task_size_64.h
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_TASK_SIZE_64_H
+#define _ASM_POWERPC_TASK_SIZE_64_H
+
+/*
+ * 64-bit user address space can have multiple limits
+ * For now supported values are:
+ */
+#define TASK_SIZE_64TB  (0x0000400000000000UL)
+#define TASK_SIZE_128TB (0x0000800000000000UL)
+#define TASK_SIZE_512TB (0x0002000000000000UL)
+#define TASK_SIZE_1PB   (0x0004000000000000UL)
+#define TASK_SIZE_2PB   (0x0008000000000000UL)
+
+/*
+ * With 52 bits in the address we can support up to 4PB of range.
+ */
+#define TASK_SIZE_4PB   (0x0010000000000000UL)
+
+/*
+ * For now 512TB is only supported with book3s and 64K linux page size.
+ */
+#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_64K_PAGES)
+/*
+ * Max value currently used:
+ */
+#define TASK_SIZE_USER64		TASK_SIZE_4PB
+#define DEFAULT_MAP_WINDOW_USER64	TASK_SIZE_128TB
+#define TASK_CONTEXT_SIZE		TASK_SIZE_512TB
+#else
+#define TASK_SIZE_USER64		TASK_SIZE_64TB
+#define DEFAULT_MAP_WINDOW_USER64	TASK_SIZE_64TB
+
+/*
+ * We don't need to allocate extended context ids for 4K page size, because we
+ * limit the max effective address on this config to 64TB.
+ */
+#define TASK_CONTEXT_SIZE TASK_SIZE_64TB
+#endif
+
+/*
+ * 32-bit user address space is 4GB - 1 page
+ * (this 1 page is needed so referencing of 0xFFFFFFFF generates EFAULT
+ */
+#define TASK_SIZE_USER32 (0x0000000100000000UL - (1 * PAGE_SIZE))
+
+#define TASK_SIZE_OF(tsk)						\
+	(test_tsk_thread_flag(tsk, TIF_32BIT) ? TASK_SIZE_USER32 :	\
+						TASK_SIZE_USER64)
+
+#define TASK_SIZE TASK_SIZE_OF(current)
+
+#define TASK_UNMAPPED_BASE_USER32 (PAGE_ALIGN(TASK_SIZE_USER32 / 4))
+#define TASK_UNMAPPED_BASE_USER64 (PAGE_ALIGN(DEFAULT_MAP_WINDOW_USER64 / 4))
+
+/*
+ * This decides where the kernel will search for a free chunk of vm space during
+ * mmap's.
+ */
+#define TASK_UNMAPPED_BASE	\
+	((is_32bit_task()) ? TASK_UNMAPPED_BASE_USER32 : TASK_UNMAPPED_BASE_USER64)
+
+/*
+ * Initial task size value for user applications. For book3s 64 we start
+ * with 128TB and conditionally enable upto 512TB
+ */
+#ifdef CONFIG_PPC_BOOK3S_64
+#define DEFAULT_MAP_WINDOW	\
+	((is_32bit_task()) ? TASK_SIZE_USER32 : DEFAULT_MAP_WINDOW_USER64)
+#else
+#define DEFAULT_MAP_WINDOW	TASK_SIZE
+#endif
+
+#define STACK_TOP_USER64 DEFAULT_MAP_WINDOW_USER64
+#define STACK_TOP_USER32 TASK_SIZE_USER32
+#define STACK_TOP_MAX TASK_SIZE_USER64
+#define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)
+
+#endif /* _ASM_POWERPC_TASK_SIZE_64_H */