riscv: extend execmem_params for generated code allocations

The memory allocations for kprobes and BPF on RISC-V are not placed in
the modules area and these custom allocations are implemented with
overrides of alloc_insn_page() and  bpf_jit_alloc_exec().

Define MODULES_VADDR and MODULES_END as VMALLOC_START and VMALLOC_END for
32 bit and slightly reorder execmem_params initialization to support both
32 and 64 bit variants, define EXECMEM_KPROBES and EXECMEM_BPF ranges in
riscv::execmem_params and drop overrides of alloc_insn_page() and
bpf_jit_alloc_exec().

Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

arch/riscv/include/asm/pgtable.h

@@ -55,6 +55,9 @@
 #define MODULES_LOWEST_VADDR	(KERNEL_LINK_ADDR - SZ_2G)
 #define MODULES_VADDR		(PFN_ALIGN((unsigned long)&_end) - SZ_2G)
 #define MODULES_END		(PFN_ALIGN((unsigned long)&_start))
+#else
+#define MODULES_VADDR		VMALLOC_START
+#define MODULES_END		VMALLOC_END
 #endif
 
 /*

arch/riscv/kernel/module.c

@@ -906,7 +906,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
 	return 0;
 }
 
-#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
+#ifdef CONFIG_MMU
 static struct execmem_info execmem_info __ro_after_init;
 
 struct execmem_info __init *execmem_arch_setup(void)
@@ -919,6 +919,18 @@ struct execmem_info __init *execmem_arch_setup(void)
 				.pgprot	= PAGE_KERNEL,
 				.alignment = 1,
 			},
+			[EXECMEM_KPROBES] = {
+				.start	= VMALLOC_START,
+				.end	= VMALLOC_END,
+				.pgprot	= PAGE_KERNEL_READ_EXEC,
+				.alignment = 1,
+			},
+			[EXECMEM_BPF] = {
+				.start	= BPF_JIT_REGION_START,
+				.end	= BPF_JIT_REGION_END,
+				.pgprot	= PAGE_KERNEL,
+				.alignment = PAGE_SIZE,
+			},
 		},
 	};
 

arch/riscv/kernel/probes/kprobes.c

@@ -104,16 +104,6 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
 	return 0;
 }
 
-#ifdef CONFIG_MMU
-void *alloc_insn_page(void)
-{
-	return  __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
-				     GFP_KERNEL, PAGE_KERNEL_READ_EXEC,
-				     VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
-				     __builtin_return_address(0));
-}
-#endif
-
 /* install breakpoint in text */
 void __kprobes arch_arm_kprobe(struct kprobe *p)
 {

arch/riscv/net/bpf_jit_core.c

@@ -219,19 +219,6 @@ u64 bpf_jit_alloc_exec_limit(void)
 	return BPF_JIT_REGION_SIZE;
 }
 
-void *bpf_jit_alloc_exec(unsigned long size)
-{
-	return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START,
-				    BPF_JIT_REGION_END, GFP_KERNEL,
-				    PAGE_KERNEL, 0, NUMA_NO_NODE,
-				    __builtin_return_address(0));
-}
-
-void bpf_jit_free_exec(void *addr)
-{
-	return vfree(addr);
-}
-
 void *bpf_arch_text_copy(void *dst, void *src, size_t len)
 {
 	int ret;