mm/execmem, arch: convert remaining overrides of module_alloc to execmem

Extend execmem parameters to accommodate more complex overrides of
module_alloc() by architectures.

This includes specification of a fallback range required by arm, arm64
and powerpc, EXECMEM_MODULE_DATA type required by powerpc, support for
allocation of KASAN shadow required by s390 and x86 and support for
late initialization of execmem required by arm64.

The core implementation of execmem_alloc() takes care of suppressing
warnings when the initial allocation fails but there is a fallback range
defined.

Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Tested-by: Liviu Dudau <liviu@dudau.co.uk>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

1 files changed, 31 insertions, 24 deletions

diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index e92da4da1b2a..b7a7a23f9f8f 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -20,6 +20,7 @@
 #include <linux/random.h>
 #include <linux/scs.h>
 #include <linux/vmalloc.h>
+#include <linux/execmem.h>
 
 #include <asm/alternative.h>
 #include <asm/insn.h>
@@ -108,41 +109,47 @@ static int __init module_init_limits(void)
 
 	return 0;
 }
-subsys_initcall(module_init_limits);
 
-void *module_alloc(unsigned long size)
+static struct execmem_info execmem_info __ro_after_init;
+
+struct execmem_info __init *execmem_arch_setup(void)
 {
-	void *p = NULL;
+	unsigned long fallback_start = 0, fallback_end = 0;
+	unsigned long start = 0, end = 0;
+
+	module_init_limits();
 
 	/*
 	 * Where possible, prefer to allocate within direct branch range of the
 	 * kernel such that no PLTs are necessary.
 	 */
 	if (module_direct_base) {
-		p = __vmalloc_node_range(size, MODULE_ALIGN,
-					 module_direct_base,
-					 module_direct_base + SZ_128M,
-					 GFP_KERNEL | __GFP_NOWARN,
-					 PAGE_KERNEL, 0, NUMA_NO_NODE,
-					 __builtin_return_address(0));
-	}
+		start = module_direct_base;
+		end = module_direct_base + SZ_128M;
 
-	if (!p && module_plt_base) {
-		p = __vmalloc_node_range(size, MODULE_ALIGN,
-					 module_plt_base,
-					 module_plt_base + SZ_2G,
-					 GFP_KERNEL | __GFP_NOWARN,
-					 PAGE_KERNEL, 0, NUMA_NO_NODE,
-					 __builtin_return_address(0));
-	}
-
-	if (!p) {
-		pr_warn_ratelimited("%s: unable to allocate memory\n",
-				    __func__);
+		if (module_plt_base) {
+			fallback_start = module_plt_base;
+			fallback_end = module_plt_base + SZ_2G;
+		}
+	} else if (module_plt_base) {
+		start = module_plt_base;
+		end = module_plt_base + SZ_2G;
 	}
 
-	/* Memory is intended to be executable, reset the pointer tag. */
-	return kasan_reset_tag(p);
+	execmem_info = (struct execmem_info){
+		.ranges = {
+			[EXECMEM_DEFAULT] = {
+				.start	= start,
+				.end	= end,
+				.pgprot	= PAGE_KERNEL,
+				.alignment = 1,
+				.fallback_start	= fallback_start,
+				.fallback_end	= fallback_end,
+			},
+		},
+	};
+
+	return &execmem_info;
 }
 
 enum aarch64_reloc_op {