xlat lib v2: Export translation context as an opaque type

At the moment, the translation context type (xlat_ctx_t) is a private
type reserved for the internal usage of the translation table library.
All exported APIs (implemented in xlat_tables_common.c) are wrappers
over the internal implementations that use such a translation context.

These wrappers unconditionally pass the current translation context
representing the memory mappings of the executing BL image. This means
that the caller has no control over which translation context the
library functions act on.

As a first step to make this code more flexible, this patch exports
the 'xlat_ctx_t' type. Note that, although the declaration of this type
is now public, its definition stays private. A macro is introduced to
statically allocate and initialize such a translation context.

The library now internally uses this macro to allocate the default
translation context for the running BL image.

Change-Id: Icece1cde4813fac19452c782b682c758142b1489
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

include/lib/xlat_tables/xlat_tables_v2.h

@@ -13,6 +13,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <xlat_mmu_helpers.h>
+#include <xlat_tables_v2_helpers.h>
 
 /* Helper macro to define entries for mmap_region_t. It creates
  * identity mappings for each region.
@@ -82,6 +83,44 @@ typedef struct mmap_region {
 	mmap_attr_t		attr;
 } mmap_region_t;
 
+/*
+ * Declare the translation context type.
+ * Its definition is private.
+ */
+typedef struct xlat_ctx xlat_ctx_t;
+
+/*
+ * Statically allocate a translation context and associated structures. Also
+ * initialize them.
+ *
+ * _ctx_name:
+ *   Prefix for the translation context variable.
+ *   E.g. If _ctx_name is 'foo', the variable will be called 'foo_xlat_ctx'.
+ *   Useful to distinguish multiple contexts from one another.
+ *
+ * _mmap_count:
+ *   Number of mmap_region_t to allocate.
+ *   Would typically be MAX_MMAP_REGIONS for the translation context describing
+ *   the BL image currently executing.
+ *
+ * _xlat_tables_count:
+ *   Number of sub-translation tables to allocate.
+ *   Would typically be MAX_XLAT_TABLES for the translation context describing
+ *   the BL image currently executing.
+ *   Note that this is only for sub-tables ; at the initial lookup level, there
+ *   is always a single table.
+ *
+ * _virt_addr_space_size, _phy_addr_space_size:
+ *   Size (in bytes) of the virtual (resp. physical) address space.
+ *   Would typically be PLAT_VIRT_ADDR_SPACE_SIZE
+ *   (resp. PLAT_PHY_ADDR_SPACE_SIZE) for the translation context describing the
+ *   BL image currently executing.
+ */
+#define REGISTER_XLAT_CONTEXT(_ctx_name, _mmap_count, _xlat_tables_count,	\
+			_virt_addr_space_size, _phy_addr_space_size)		\
+	_REGISTER_XLAT_CONTEXT(_ctx_name, _mmap_count, _xlat_tables_count,	\
+		_virt_addr_space_size, _phy_addr_space_size)
+
 /* Generic translation table APIs */
 
 /*

include/lib/xlat_tables/xlat_tables_v2_helpers.h

+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * This header file contains internal definitions that are not supposed to be
+ * used outside of this library code.
+ */
+
+#ifndef __XLAT_TABLES_V2_HELPERS_H__
+#define __XLAT_TABLES_V2_HELPERS_H__
+
+#ifndef __XLAT_TABLES_V2_H__
+#error "Do not include this header file directly. Include xlat_tables_v2.h instead."
+#endif
+
+#ifndef __ASSEMBLY__
+
+#include <cassert.h>
+#include <platform_def.h>
+#include <stddef.h>
+#include <xlat_tables_arch.h>
+#include <xlat_tables_defs.h>
+
+/* Forward declaration */
+struct mmap_region;
+
+/* Struct that holds all information about the translation tables. */
+struct xlat_ctx {
+	/*
+	 * Max allowed Virtual and Physical Addresses.
+	 */
+	unsigned long long pa_max_address;
+	uintptr_t va_max_address;
+
+	/*
+	 * Array of all memory regions stored in order of ascending end address
+	 * and ascending size to simplify the code that allows overlapping
+	 * regions. The list is terminated by the first entry with size == 0.
+	 * The max size of the list is stored in `mmap_num`. `mmap` points to an
+	 * array of mmap_num + 1 elements, so that there is space for the final
+	 * null entry.
+	 */
+	struct mmap_region *mmap;
+	unsigned int mmap_num;
+
+	/*
+	 * Array of finer-grain translation tables.
+	 * For example, if the initial lookup level is 1 then this array would
+	 * contain both level-2 and level-3 entries.
+	 */
+	uint64_t (*tables)[XLAT_TABLE_ENTRIES];
+	unsigned int tables_num;
+	/*
+	 * Keep track of how many regions are mapped in each table. The base
+	 * table can't be unmapped so it isn't needed to keep track of it.
+	 */
+#if PLAT_XLAT_TABLES_DYNAMIC
+	int *tables_mapped_regions;
+#endif /* PLAT_XLAT_TABLES_DYNAMIC */
+
+	unsigned int next_table;
+
+	/*
+	 * Base translation table. It doesn't need to have the same amount of
+	 * entries as the ones used for other levels.
+	 */
+	uint64_t *base_table;
+	unsigned int base_table_entries;
+
+	/*
+	* Max Physical and Virtual addresses currently in use by the
+	* translation tables. These might get updated as we map/unmap memory
+	* regions but they will never go beyond pa/va_max_address.
+	*/
+	unsigned long long max_pa;
+	uintptr_t max_va;
+
+	/* Level of the base translation table. */
+	unsigned int base_level;
+
+	/* Set to 1 when the translation tables are initialized. */
+	unsigned int initialized;
+
+	/*
+	 * Bit mask that has to be ORed to the rest of a translation table
+	 * descriptor in order to prohibit execution of code at the exception
+	 * level of this translation context.
+	 */
+	uint64_t execute_never_mask;
+};
+
+#if PLAT_XLAT_TABLES_DYNAMIC
+#define _ALLOC_DYNMAP_STRUCT(_ctx_name, _xlat_tables_count)		\
+	static int _ctx_name##_mapped_regions[_xlat_tables_count];
+
+#define _REGISTER_DYNMAP_STRUCT(_ctx_name)				\
+	.tables_mapped_regions = _ctx_name##_mapped_regions,
+#else
+#define _ALLOC_DYNMAP_STRUCT(_ctx_name, _xlat_tables_count)		\
+	/* do nothing */
+
+#define _REGISTER_DYNMAP_STRUCT(_ctx_name)				\
+	/* do nothing */
+#endif /* PLAT_XLAT_TABLES_DYNAMIC */
+
+
+#define _REGISTER_XLAT_CONTEXT(_ctx_name, _mmap_count, _xlat_tables_count,	\
+			_virt_addr_space_size, _phy_addr_space_size)		\
+	CASSERT(CHECK_VIRT_ADDR_SPACE_SIZE(_virt_addr_space_size),		\
+		assert_invalid_virtual_addr_space_size_for_##_ctx_name);	\
+										\
+	CASSERT(CHECK_PHY_ADDR_SPACE_SIZE(_phy_addr_space_size),		\
+		assert_invalid_physical_addr_space_sizefor_##_ctx_name);	\
+										\
+	static mmap_region_t _ctx_name##_mmap[_mmap_count + 1];			\
+										\
+	static uint64_t _ctx_name##_xlat_tables[_xlat_tables_count]		\
+		[XLAT_TABLE_ENTRIES]						\
+		__aligned(XLAT_TABLE_SIZE) __section("xlat_table");		\
+										\
+	static uint64_t _ctx_name##_base_xlat_table				\
+		[GET_NUM_BASE_LEVEL_ENTRIES(_virt_addr_space_size)]		\
+		__aligned(GET_NUM_BASE_LEVEL_ENTRIES(_virt_addr_space_size)	\
+			* sizeof(uint64_t));					\
+										\
+	_ALLOC_DYNMAP_STRUCT(_ctx_name, _xlat_tables_count)			\
+										\
+	static xlat_ctx_t _ctx_name##_xlat_ctx = {				\
+		.va_max_address = (_virt_addr_space_size) - 1,			\
+		.pa_max_address = (_phy_addr_space_size) - 1,			\
+		.mmap = _ctx_name##_mmap,					\
+		.mmap_num = _mmap_count,					\
+		.base_level = GET_XLAT_TABLE_LEVEL_BASE(_virt_addr_space_size),	\
+		.base_table = _ctx_name##_base_xlat_table,			\
+		.base_table_entries =						\
+			GET_NUM_BASE_LEVEL_ENTRIES(_virt_addr_space_size),	\
+		.tables = _ctx_name##_xlat_tables,				\
+		.tables_num = _xlat_tables_count,				\
+		 _REGISTER_DYNMAP_STRUCT(_ctx_name)				\
+		.max_pa = 0,							\
+		.max_va = 0,							\
+		.next_table = 0,						\
+		.initialized = 0,						\
+	}
+
+#endif /*__ASSEMBLY__*/
+
+#endif /* __XLAT_TABLES_V2_HELPERS_H__ */

lib/xlat_tables_v2/xlat_tables_common.c

@@ -7,7 +7,6 @@
 #include <arch.h>
 #include <arch_helpers.h>
 #include <assert.h>
-#include <cassert.h>
 #include <common_def.h>
 #include <debug.h>
 #include <errno.h>
@@ -38,59 +37,12 @@
 # endif
 #endif
 
-CASSERT(CHECK_VIRT_ADDR_SPACE_SIZE(PLAT_VIRT_ADDR_SPACE_SIZE),
-	assert_invalid_virtual_addr_space_size);
-
-CASSERT(CHECK_PHY_ADDR_SPACE_SIZE(PLAT_PHY_ADDR_SPACE_SIZE),
-	assert_invalid_physical_addr_space_size);
-
-#define NUM_BASE_LEVEL_ENTRIES	\
-	GET_NUM_BASE_LEVEL_ENTRIES(PLAT_VIRT_ADDR_SPACE_SIZE)
-
-#define XLAT_TABLE_LEVEL_BASE	\
-	GET_XLAT_TABLE_LEVEL_BASE(PLAT_VIRT_ADDR_SPACE_SIZE)
-
 /*
- * Private variables used by the TF
+ * Allocate and initialise the default translation context for the BL image
+ * currently executing.
  */
-static mmap_region_t tf_mmap[MAX_MMAP_REGIONS + 1];
-
-static uint64_t tf_xlat_tables[MAX_XLAT_TABLES][XLAT_TABLE_ENTRIES]
-			__aligned(XLAT_TABLE_SIZE) __section("xlat_table");
-
-static uint64_t tf_base_xlat_table[NUM_BASE_LEVEL_ENTRIES]
-		__aligned(NUM_BASE_LEVEL_ENTRIES * sizeof(uint64_t));
-
-#if PLAT_XLAT_TABLES_DYNAMIC
-static int xlat_tables_mapped_regions[MAX_XLAT_TABLES];
-#endif /* PLAT_XLAT_TABLES_DYNAMIC */
-
-xlat_ctx_t tf_xlat_ctx = {
-
-	.pa_max_address = PLAT_PHY_ADDR_SPACE_SIZE - 1,
-	.va_max_address = PLAT_VIRT_ADDR_SPACE_SIZE - 1,
-
-	.mmap = tf_mmap,
-	.mmap_num = MAX_MMAP_REGIONS,
-
-	.tables = tf_xlat_tables,
-	.tables_num = MAX_XLAT_TABLES,
-#if PLAT_XLAT_TABLES_DYNAMIC
-	.tables_mapped_regions = xlat_tables_mapped_regions,
-#endif /* PLAT_XLAT_TABLES_DYNAMIC */
-
-	.base_table = tf_base_xlat_table,
-	.base_table_entries = NUM_BASE_LEVEL_ENTRIES,
-
-	.max_pa = 0,
-	.max_va = 0,
-
-	.next_table = 0,
-
-	.base_level = XLAT_TABLE_LEVEL_BASE,
-
-	.initialized = 0
-};
+REGISTER_XLAT_CONTEXT(tf, MAX_MMAP_REGIONS, MAX_XLAT_TABLES,
+		PLAT_VIRT_ADDR_SPACE_SIZE, PLAT_PHY_ADDR_SPACE_SIZE);
 
 void mmap_add_region(unsigned long long base_pa, uintptr_t base_va,
 			size_t size, mmap_attr_t attr)
@@ -143,8 +95,8 @@ void init_xlat_tables(void)
 	init_xlation_table(&tf_xlat_ctx);
 	xlat_tables_print(&tf_xlat_ctx);
 
-	assert(tf_xlat_ctx.max_va <= PLAT_VIRT_ADDR_SPACE_SIZE - 1);
-	assert(tf_xlat_ctx.max_pa <= PLAT_PHY_ADDR_SPACE_SIZE - 1);
+	assert(tf_xlat_ctx.max_va <= tf_xlat_ctx.va_max_address);
+	assert(tf_xlat_ctx.max_pa <= tf_xlat_ctx.pa_max_address);
 
 	init_xlat_tables_arch(tf_xlat_ctx.max_pa);
 }

lib/xlat_tables_v2/xlat_tables_private.h

@@ -10,73 +10,6 @@
 #include <platform_def.h>
 #include <xlat_tables_defs.h>
 
-/* Struct that holds all information about the translation tables. */
-typedef struct {
-
-	/*
-	 * Max allowed Virtual and Physical Addresses.
-	 */
-	unsigned long long pa_max_address;
-	uintptr_t va_max_address;
-
-	/*
-	 * Array of all memory regions stored in order of ascending end address
-	 * and ascending size to simplify the code that allows overlapping
-	 * regions. The list is terminated by the first entry with size == 0.
-	 * The max size of the list is stored in `mmap_num`. `mmap` points to an
-	 * array of mmap_num + 1 elements, so that there is space for the final
-	 * null entry.
-	 */
-	mmap_region_t *mmap;
-	unsigned int mmap_num;
-
-	/*
-	 * Array of finer-grain translation tables.
-	 * For example, if the initial lookup level is 1 then this array would
-	 * contain both level-2 and level-3 entries.
-	 */
-	uint64_t (*tables)[XLAT_TABLE_ENTRIES];
-	unsigned int tables_num;
-	/*
-	 * Keep track of how many regions are mapped in each table. The base
-	 * table can't be unmapped so it isn't needed to keep track of it.
-	 */
-#if PLAT_XLAT_TABLES_DYNAMIC
-	int *tables_mapped_regions;
-#endif /* PLAT_XLAT_TABLES_DYNAMIC */
-
-	unsigned int next_table;
-
-	/*
-	 * Base translation table. It doesn't need to have the same amount of
-	 * entries as the ones used for other levels.
-	 */
-	uint64_t *base_table;
-	unsigned int base_table_entries;
-
-	/*
-	 * Max Physical and Virtual addresses currently in use by the
-	 * translation tables. These might get updated as we map/unmap memory
-	 * regions but they will never go beyond pa/va_max_address.
-	 */
-	unsigned long long max_pa;
-	uintptr_t max_va;
-
-	/* Level of the base translation table. */
-	unsigned int base_level;
-
-	/* Set to 1 when the translation tables are initialized. */
-	unsigned int initialized;
-
-	/*
-	 * Bit mask that has to be ORed to the rest of a translation table
-	 * descriptor in order to prohibit execution of code at the exception
-	 * level of this translation context.
-	 */
-	uint64_t execute_never_mask;
-
-} xlat_ctx_t;
-
 #if PLAT_XLAT_TABLES_DYNAMIC
 /*
  * Shifts and masks to access fields of an mmap_attr_t