mm: introduce CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK

Sometimes the generic address range checker is not adequate
(think Xtensa cached/uncached pointers). This provides a way
to implement custom memory range checkers for those
situations. When enabled, sys_mm_is_phys_addr_in_range()
and sys_mm_is_virt_addr_in_range() must be implemented.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>

include/zephyr/sys/mem_manage.h

@@ -143,12 +143,53 @@ struct k_mem_paging_histogram_t {
 #endif /* CONFIG_DEMAND_PAGING_TIMING_HISTOGRAM */
 };
 
+/**
+ * @brief Check if a physical address is within range of physical memory.
+ *
+ * This checks if the physical address (@p virt) is within
+ * permissible range, e.g. between
+ * :kconfig:option:`CONFIG_SRAM_BASE_ADDRESS` and
+ * (:kconfig:option:`CONFIG_SRAM_BASE_ADDRESS` +
+ *  :kconfig:option:`CONFIG_SRAM_SIZE`).
+ *
+ * @note Only used if
+ * :kconfig:option:`CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK`
+ * is enabled.
+ *
+ * @param phys Physical address to be checked.
+ *
+ * @return True if physical address is within range, false if not.
+ */
+bool sys_mm_is_phys_addr_in_range(uintptr_t phys);
+
+/**
+ * @brief Check if a virtual address is within range of virtual memory.
+ *
+ * This checks if the virtual address (@p virt) is within
+ * permissible range, e.g. between
+ * :kconfig:option:`CONFIG_KERNEL_VM_BASE` and
+ * (:kconfig:option:`CONFIG_KERNEL_VM_BASE` +
+ *  :kconfig:option:`CONFIG_KERNEL_VM_SIZE`).
+ *
+ * @note Only used if
+ * :kconfig:option:`CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK`
+ * is enabled.
+ *
+ * @param virt Virtual address to be checked.
+ *
+ * @return True if virtual address is within range, false if not.
+ */
+bool sys_mm_is_virt_addr_in_range(void *virt);
+
 /* Just like Z_MEM_PHYS_ADDR() but with type safety and assertions */
 static inline uintptr_t z_mem_phys_addr(void *virt)
 {
 	uintptr_t addr = (uintptr_t)virt;
 
-#ifdef CONFIG_MMU
+#if defined(CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK)
+	__ASSERT(sys_mm_is_virt_addr_in_range(virt),
+		 "address %p not in permanent mappings", virt);
+#elif defined(CONFIG_MMU)
 	__ASSERT(
 #if CONFIG_KERNEL_VM_BASE != 0
 		 (addr >= CONFIG_KERNEL_VM_BASE) &&
@@ -178,6 +219,10 @@ static inline uintptr_t z_mem_phys_addr(void *virt)
 /* Just like Z_MEM_VIRT_ADDR() but with type safety and assertions */
 static inline void *z_mem_virt_addr(uintptr_t phys)
 {
+#if defined(CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK)
+	__ASSERT(sys_mm_is_phys_addr_in_range(phys),
+		"physical address 0x%lx not in RAM", (unsigned long)phys);
+#else
 	__ASSERT(
 #if CONFIG_SRAM_BASE_ADDRESS != 0
 		 (phys >= CONFIG_SRAM_BASE_ADDRESS) &&
@@ -185,6 +230,7 @@ static inline void *z_mem_virt_addr(uintptr_t phys)
 		 (phys < (CONFIG_SRAM_BASE_ADDRESS +
 			  (CONFIG_SRAM_SIZE * 1024UL))),
 		 "physical address 0x%lx not in RAM", (unsigned long)phys);
+#endif
 
 	/* TODO add assertion that this page frame is pinned to boot mapping,
 	 * the above check won't be sufficient with demand paging

kernel/Kconfig.vm

@@ -198,4 +198,13 @@ config DEMAND_PAGING_TIMING_HISTOGRAM_NUM_BINS
 endif # DEMAND_PAGING
 endif # MMU
 
+config KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK
+	bool
+	help
+	  Use custom memory range check functions instead of the generic
+	  checks in z_mem_phys_addr() and z_mem_virt_addr().
+
+	  sys_mm_is_phys_addr_in_range() and
+	  sys_mm_is_virt_addr_in_range() must be implemented.
+
 endmenu # Virtual Memory Support