[PATCH 03/13] mm/jitalloc, arch: convert simple overrides of module_alloc to jitalloc

From: Mike Rapoport
Date: Thu Jun 01 2023 - 06:17:56 EST


From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>

Several architectures override module_alloc() only to define address
range for code allocations different than VMALLOC address space.

Provide a generic implementation in jitalloc that uses the parameters
for address space ranges, required alignment and page protections
provided by architectures.

The architecures must fill jit_alloc_params structure and implement
jit_alloc_arch_params() that returns a pointer to that structure. This
way the jitalloc initialization won't be called from every architecure,
but rather from a central place, namely initialization of the core
memory management.

Signed-off-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
---
arch/loongarch/kernel/module.c | 14 ++++++++--
arch/mips/kernel/module.c | 16 ++++++++---
arch/nios2/kernel/module.c | 15 ++++++----
arch/parisc/kernel/module.c | 18 ++++++++----
arch/riscv/kernel/module.c | 16 +++++++----
arch/sparc/kernel/module.c | 39 +++++++++++---------------
include/linux/jitalloc.h | 31 +++++++++++++++++++++
mm/jitalloc.c | 51 ++++++++++++++++++++++++++++++++++
mm/mm_init.c | 2 ++
9 files changed, 156 insertions(+), 46 deletions(-)

diff --git a/arch/loongarch/kernel/module.c b/arch/loongarch/kernel/module.c
index b8b86088b2dd..1d5e00874ae7 100644
--- a/arch/loongarch/kernel/module.c
+++ b/arch/loongarch/kernel/module.c
@@ -18,6 +18,7 @@
#include <linux/ftrace.h>
#include <linux/string.h>
#include <linux/kernel.h>
+#include <linux/jitalloc.h>
#include <asm/alternative.h>
#include <asm/inst.h>

@@ -469,10 +470,17 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
return 0;
}

-void *module_alloc(unsigned long size)
+static struct jit_alloc_params jit_alloc_params = {
+ .alignment = 1,
+ .text.pgprot = PAGE_KERNEL,
+};
+
+struct jit_alloc_params *jit_alloc_arch_params(void)
{
- return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
- GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0));
+ jit_alloc_params.text.start = MODULES_VADDR;
+ jit_alloc_params.text.end = MODULES_END;
+
+ return &jit_alloc_params;
}

static void module_init_ftrace_plt(const Elf_Ehdr *hdr,
diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c
index 0c936cbf20c5..f762c697ab9c 100644
--- a/arch/mips/kernel/module.c
+++ b/arch/mips/kernel/module.c
@@ -20,6 +20,7 @@
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/jump_label.h>
+#include <linux/jitalloc.h>

extern void jump_label_apply_nops(struct module *mod);

@@ -33,11 +34,18 @@ static LIST_HEAD(dbe_list);
static DEFINE_SPINLOCK(dbe_lock);

#ifdef MODULE_START
-void *module_alloc(unsigned long size)
+
+static struct jit_alloc_params jit_alloc_params = {
+ .alignment = 1,
+ .text.start = MODULE_START,
+ .text.end = MODULE_END,
+};
+
+struct jit_alloc_params *jit_alloc_arch_params(void)
{
- return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
- GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
+ jit_alloc_params.text.pgprot = PAGE_KERNEL;
+
+ return &jit_alloc_params;
}
#endif

diff --git a/arch/nios2/kernel/module.c b/arch/nios2/kernel/module.c
index 9c97b7513853..b41d52775ec2 100644
--- a/arch/nios2/kernel/module.c
+++ b/arch/nios2/kernel/module.c
@@ -18,15 +18,20 @@
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
+#include <linux/jitalloc.h>

#include <asm/cacheflush.h>

-void *module_alloc(unsigned long size)
+static struct jit_alloc_params jit_alloc_params = {
+ .alignment = 1,
+ .text.pgprot = PAGE_KERNEL_EXEC,
+ .text.start = MODULES_VADDR,
+ .text.end = MODULES_END,
+};
+
+struct jit_alloc_params *jit_alloc_arch_params(void)
{
- return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
- GFP_KERNEL, PAGE_KERNEL_EXEC,
- VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
- __builtin_return_address(0));
+ return &jit_alloc_params;
}

int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c
index f6e38c4d3904..49fdf741fd24 100644
--- a/arch/parisc/kernel/module.c
+++ b/arch/parisc/kernel/module.c
@@ -49,6 +49,7 @@
#include <linux/bug.h>
#include <linux/mm.h>
#include <linux/slab.h>
+#include <linux/jitalloc.h>

#include <asm/unwind.h>
#include <asm/sections.h>
@@ -173,15 +174,20 @@ static inline int reassemble_22(int as22)
((as22 & 0x0003ff) << 3));
}

-void *module_alloc(unsigned long size)
-{
+static struct jit_alloc_params jit_alloc_params = {
+ .alignment = 1,
/* using RWX means less protection for modules, but it's
* easier than trying to map the text, data, init_text and
* init_data correctly */
- return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
- GFP_KERNEL,
- PAGE_KERNEL_RWX, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
+ .text.pgprot = PAGE_KERNEL_RWX,
+ .text.end = VMALLOC_END,
+};
+
+struct jit_alloc_params *jit_alloc_arch_params(void)
+{
+ jit_alloc_params.text.start = VMALLOC_START;
+
+ return &jit_alloc_params;
}

#ifndef CONFIG_64BIT
diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 7c651d55fcbd..731255654c94 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -11,6 +11,7 @@
#include <linux/vmalloc.h>
#include <linux/sizes.h>
#include <linux/pgtable.h>
+#include <linux/jitalloc.h>
#include <asm/alternative.h>
#include <asm/sections.h>

@@ -436,12 +437,17 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
}

#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
-void *module_alloc(unsigned long size)
+static struct jit_alloc_params jit_alloc_params = {
+ .alignment = 1,
+ .text.pgprot = PAGE_KERNEL,
+};
+
+struct jit_alloc_params *jit_alloc_arch_params(void)
{
- return __vmalloc_node_range(size, 1, MODULES_VADDR,
- MODULES_END, GFP_KERNEL,
- PAGE_KERNEL, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
+ jit_alloc_params.text.start = MODULES_VADDR;
+ jit_alloc_params.text.end = MODULES_END;
+
+ return &jit_alloc_params;
}
#endif

diff --git a/arch/sparc/kernel/module.c b/arch/sparc/kernel/module.c
index 66c45a2764bc..03f0de693b4d 100644
--- a/arch/sparc/kernel/module.c
+++ b/arch/sparc/kernel/module.c
@@ -14,6 +14,11 @@
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/mm.h>
+#include <linux/jitalloc.h>
+
+#ifdef CONFIG_SPARC64
+#include <linux/jump_label.h>
+#endif

#include <asm/processor.h>
#include <asm/spitfire.h>
@@ -21,34 +26,22 @@

#include "entry.h"

+static struct jit_alloc_params jit_alloc_params = {
+ .alignment = 1,
#ifdef CONFIG_SPARC64
-
-#include <linux/jump_label.h>
-
-static void *module_map(unsigned long size)
-{
- if (PAGE_ALIGN(size) > MODULES_LEN)
- return NULL;
- return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
- GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
-}
+ .text.start = MODULES_VADDR,
+ .text.end = MODULES_END,
#else
-static void *module_map(unsigned long size)
-{
- return vmalloc(size);
-}
-#endif /* CONFIG_SPARC64 */
+ .text.start = VMALLOC_START,
+ .text.end = VMALLOC_END,
+#endif
+};

-void *module_alloc(unsigned long size)
+struct jit_alloc_params *jit_alloc_arch_params(void)
{
- void *ret;
-
- ret = module_map(size);
- if (ret)
- memset(ret, 0, size);
+ jit_alloc_params.text.pgprot = PAGE_KERNEL;

- return ret;
+ return &jit_alloc_params;
}

/* Make generic code ignore STT_REGISTER dummy undefined symbols. */
diff --git a/include/linux/jitalloc.h b/include/linux/jitalloc.h
index 9517e64e474d..34fddef23dea 100644
--- a/include/linux/jitalloc.h
+++ b/include/linux/jitalloc.h
@@ -4,7 +4,38 @@

#include <linux/types.h>

+/**
+ * struct jit_address_space - address space definition for code and
+ * related data allocations
+ * @pgprot: permisssions for memory in this address space
+ * @start: address space start
+ * @end: address space end (inclusive)
+ */
+struct jit_address_space {
+ pgprot_t pgprot;
+ unsigned long start;
+ unsigned long end;
+};
+
+/**
+ * struct jit_alloc_params - architecure parameters for code allocations
+ * @text: address space range for text allocations
+ * @alignment: alignment required for text allocations
+ */
+struct jit_alloc_params {
+ struct jit_address_space text;
+ unsigned int alignment;
+};
+
+struct jit_alloc_params *jit_alloc_arch_params(void);
+
void jit_free(void *buf);
void *jit_text_alloc(size_t len);

+#ifdef CONFIG_JIT_ALLOC
+void jit_alloc_init(void);
+#else
+static inline void jit_alloc_init(void) {}
+#endif
+
#endif /* _LINUX_JITALLOC_H */
diff --git a/mm/jitalloc.c b/mm/jitalloc.c
index f15262202a1a..3e63eeb8bf4b 100644
--- a/mm/jitalloc.c
+++ b/mm/jitalloc.c
@@ -2,8 +2,22 @@

#include <linux/moduleloader.h>
#include <linux/vmalloc.h>
+#include <linux/mm.h>
#include <linux/jitalloc.h>

+static struct jit_alloc_params jit_alloc_params;
+
+static void *jit_alloc(size_t len, unsigned int alignment, pgprot_t pgprot,
+ unsigned long start, unsigned long end)
+{
+ if (PAGE_ALIGN(len) > (end - start))
+ return NULL;
+
+ return __vmalloc_node_range(len, alignment, start, end, GFP_KERNEL,
+ pgprot, VM_FLUSH_RESET_PERMS,
+ NUMA_NO_NODE, __builtin_return_address(0));
+}
+
void jit_free(void *buf)
{
/*
@@ -16,5 +30,42 @@ void jit_free(void *buf)

void *jit_text_alloc(size_t len)
{
+ if (jit_alloc_params.text.start) {
+ unsigned int align = jit_alloc_params.alignment;
+ pgprot_t pgprot = jit_alloc_params.text.pgprot;
+ unsigned long start = jit_alloc_params.text.start;
+ unsigned long end = jit_alloc_params.text.end;
+
+ return jit_alloc(len, align, pgprot, start, end);
+ }
+
return module_alloc(len);
}
+
+struct jit_alloc_params * __weak jit_alloc_arch_params(void)
+{
+ return NULL;
+}
+
+static bool jit_alloc_validate_params(struct jit_alloc_params *p)
+{
+ if (!p->alignment || !p->text.start || !p->text.end ||
+ !pgprot_val(p->text.pgprot)) {
+ pr_crit("Invalid parameters for jit allocator, module loading will fail");
+ return false;
+ }
+
+ return true;
+}
+
+void jit_alloc_init(void)
+{
+ struct jit_alloc_params *p = jit_alloc_arch_params();
+
+ if (p) {
+ if (!jit_alloc_validate_params(p))
+ return;
+
+ jit_alloc_params = *p;
+ }
+}
diff --git a/mm/mm_init.c b/mm/mm_init.c
index 7f7f9c677854..5f50e75bbc5f 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -26,6 +26,7 @@
#include <linux/pgtable.h>
#include <linux/swap.h>
#include <linux/cma.h>
+#include <linux/jitalloc.h>
#include "internal.h"
#include "slab.h"
#include "shuffle.h"
@@ -2747,4 +2748,5 @@ void __init mm_core_init(void)
pti_init();
kmsan_init_runtime();
mm_cache_init();
+ jit_alloc_init();
}
--
2.35.1