Subject: [PATCH v3 08/13] riscv: extend execmem_params for generated code allocations

From: Mike Rapoport <[email-masked]>
Date: Mon, 18 Sep 2023 10:29:50 +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]>
---
 arch/riscv/kernel/module.c         | 21 ++++++++++++++++++++-
 arch/riscv/kernel/probes/kprobes.c | 10 ----------
 arch/riscv/net/bpf_jit_core.c      | 13 -------------
 3 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 343a0edfb6dd..31505ecb5c72 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -436,20 +436,39 @@ 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_params execmem_params __ro_after_init = {
 	.ranges = {
 		[EXECMEM_DEFAULT] = {
 			.pgprot = PAGE_KERNEL,
 			.alignment = 1,
 		},
+		[EXECMEM_KPROBES] = {
+			.pgprot = PAGE_KERNEL_READ_EXEC,
+			.alignment = 1,
+		},
+		[EXECMEM_BPF] = {
+			.pgprot = PAGE_KERNEL,
+			.alignment = 1,
+		},
 	},
 };
 
 struct execmem_params __init *execmem_arch_params(void)
 {
+#ifdef CONFIG_64BIT
 	execmem_params.ranges[EXECMEM_DEFAULT].start = MODULES_VADDR;
 	execmem_params.ranges[EXECMEM_DEFAULT].end = MODULES_END;
+#else
+	execmem_params.ranges[EXECMEM_DEFAULT].start = VMALLOC_START;
+	execmem_params.ranges[EXECMEM_DEFAULT].end = VMALLOC_END;
+#endif
+
+	execmem_params.ranges[EXECMEM_KPROBES].start = VMALLOC_START;
+	execmem_params.ranges[EXECMEM_KPROBES].end = VMALLOC_END;
+
+	execmem_params.ranges[EXECMEM_BPF].start = BPF_JIT_REGION_START;
+	execmem_params.ranges[EXECMEM_BPF].end = BPF_JIT_REGION_END;
 
 	return &execmem_params;
 }
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 7b70ccb7fec3..c8a758f0882b 100644
--- a/arch/riscv/net/bpf_jit_core.c
+++ b/arch/riscv/net/bpf_jit_core.c
@@ -218,19 +218,6 @@ 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;
-- 
2.39.2