sections: move and rename core_kernel_data() to is_kernel_core_data()

Move core_kernel_data() into sections.h and rename it to
is_kernel_core_data(), also make it return bool value, then update all the
callers.

Link: https://lkml.kernel.org/r/20210930071143.63410-4-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-generic/sections.h

@@ -128,6 +128,22 @@ static inline bool init_section_intersects(void *virt, size_t size)
 	return memory_intersects(__init_begin, __init_end, virt, size);
 }
 
+/**
+ * is_kernel_core_data - checks if the pointer address is located in the
+ *			 .data section
+ *
+ * @addr: address to check
+ *
+ * Returns: true if the address is located in .data, false otherwise.
+ * Note: On some archs it may return true for core RODATA, and false
+ *       for others. But will always be true for core RW data.
+ */
+static inline bool is_kernel_core_data(unsigned long addr)
+{
+	return addr >= (unsigned long)_sdata &&
+	       addr < (unsigned long)_edata;
+}
+
 /**
  * is_kernel_rodata - checks if the pointer address is located in the
  *                    .rodata section

include/linux/kernel.h

@@ -227,7 +227,6 @@ extern char *next_arg(char *args, char **param, char **val);
 
 extern int core_kernel_text(unsigned long addr);
 extern int init_kernel_text(unsigned long addr);
-extern int core_kernel_data(unsigned long addr);
 extern int __kernel_text_address(unsigned long addr);
 extern int kernel_text_address(unsigned long addr);
 extern int func_ptr_is_kernel_text(void *ptr);

kernel/extable.c

@@ -82,24 +82,6 @@ int notrace core_kernel_text(unsigned long addr)
 	return 0;
 }
 
-/**
- * core_kernel_data - tell if addr points to kernel data
- * @addr: address to test
- *
- * Returns true if @addr passed in is from the core kernel data
- * section.
- *
- * Note: On some archs it may return true for core RODATA, and false
- *  for others. But will always be true for core RW data.
- */
-int core_kernel_data(unsigned long addr)
-{
-	if (addr >= (unsigned long)_sdata &&
-	    addr < (unsigned long)_edata)
-		return 1;
-	return 0;
-}
-
 int __kernel_text_address(unsigned long addr)
 {
 	if (kernel_text_address(addr))

kernel/trace/ftrace.c

@@ -323,7 +323,7 @@ int __register_ftrace_function(struct ftrace_ops *ops)
 	if (!ftrace_enabled && (ops->flags & FTRACE_OPS_FL_PERMANENT))
 		return -EBUSY;
 
-	if (!core_kernel_data((unsigned long)ops))
+	if (!is_kernel_core_data((unsigned long)ops))
 		ops->flags |= FTRACE_OPS_FL_DYNAMIC;
 
 	add_ftrace_ops(&ftrace_ops_list, ops);

net/sysctl_net.c

@@ -144,7 +144,7 @@ static void ensure_safe_net_sysctl(struct net *net, const char *path,
 		addr = (unsigned long)ent->data;
 		if (is_module_address(addr))
 			where = "module";
-		else if (core_kernel_data(addr))
+		else if (is_kernel_core_data(addr))
 			where = "kernel";
 		else
 			continue;