Subject: [PATCH v6 09/16] riscv: extend execmem_params for generated code allocations

From: Mike Rapoport <[email-masked]>
Date: Fri, 26 Apr 2024 11:28:47 +0300

From: "Mike Rapoport (IBM)" <[email-masked]>

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().

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) <[email-masked]>
Reviewed-by: Alexandre Ghiti <[email-masked]>
---
 arch/riscv/kernel/module.c         | 28 +++++++++++++++++++++++++---
 arch/riscv/kernel/probes/kprobes.c | 10 ----------
 arch/riscv/net/bpf_jit_core.c      | 13 -------------
 3 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 182904127ba0..2ecbacbc9993 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -906,19 +906,41 @@ 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)
 {
+	unsigned long start, end;
+
+	if (IS_ENABLED(CONFIG_64BIT)) {
+		start = MODULES_VADDR;
+		end = MODULES_END;
+	} else {
+		start = VMALLOC_START;
+		end = VMALLOC_END;
+	}
+
 	execmem_info = (struct execmem_info){
 		.ranges = {
 			[EXECMEM_DEFAULT] = {
-				.start	= MODULES_VADDR,
-				.end	= MODULES_END,
+				.start	= start,
+				.end	= end,
 				.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,
+			},
 		},
 	};
 
diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
index 2f08c14a933d..e64f2f3064eb 100644
--- a/arch/riscv/kernel/probes/kprobes.c
+++ b/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)
 {
diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c
index 6b3acac30c06..e238fdbd5dbc 100644
--- a/arch/riscv/net/bpf_jit_core.c
+++ b/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;
-- 
2.43.0