[PATCH v5 03/15] nios2: define virtual address space for modules

Mike Rapoport
2024-04-22T09:46:05Z

nios2 uses kmalloc() to implement module_alloc() because CALL26/PCREL26
cannot reach all of vmalloc address space.

Define module space as 32MiB below the kernel base and switch nios2 to
use vmalloc for module allocations.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
---
arch/nios2/include/asm/pgtable.h | 5 ++++-
arch/nios2/kernel/module.c | 19 ++++---------------
2 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
index d052dfcbe8d3..eab87c6beacb 100644
--- a/arch/nios2/include/asm/pgtable.h
+++ b/arch/nios2/include/asm/pgtable.h
@@ -25,7 +25,10 @@
#include <asm-generic/pgtable-nopmd.h>

#define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
-#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
+#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M - 1)
+
+#define MODULES_VADDR (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M)
+#define MODULES_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)

struct mm_struct;

diff --git a/arch/nios2/kernel/module.c b/arch/nios2/kernel/module.c
index 76e0a42d6e36..9c97b7513853 100644
--- a/arch/nios2/kernel/module.c
+++ b/arch/nios2/kernel/module.c
@@ -21,23 +21,12 @@

#include <asm/cacheflush.h>

-/*
- * Modules should NOT be allocated with kmalloc for (obvious) reasons.
- * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
- * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
- * addresses in 0xc0000000)
- */
void *module_alloc(unsigned long size)
{
- if (size == 0)
- return NULL;
- return kmalloc(size, GFP_KERNEL);
-}
-
-/* Free memory returned from module_alloc */
-void module_memfree(void *module_region)
-{
- kfree(module_region);
+ 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));
}

int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,