arm64: Change elfcore for_each_mte_vma() to use VMA iterator

Rework for_each_mte_vma() to use a VMA iterator instead of an explicit
linked-list. This will allow easy integration with the maple tree work
which removes the VMA list altogether.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220218023650.672072-1-Liam.Howlett@oracle.com
[will: Folded in fix from Catalin]
Link: https://lore.kernel.org/r/YhUcywqIhmHvX6dG@arm.com
Signed-off--by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/kernel/elfcore.c b/arch/arm64/kernel/elfcore.c
index 3455ee4..3ed39c6 100644 (file)
--- a/arch/arm64/kernel/elfcore.c
+++ b/arch/arm64/kernel/elfcore.c
@@ -8,9 +8,16 @@
 #include <asm/cpufeature.h>
 #include <asm/mte.h>
 
-#define for_each_mte_vma(tsk, vma)                                     \
+#ifndef VMA_ITERATOR
+#define VMA_ITERATOR(name, mm, addr)   \
+       struct mm_struct *name = mm
+#define for_each_vma(vmi, vma)         \
+       for (vma = vmi->mmap; vma; vma = vma->vm_next)
+#endif
+
+#define for_each_mte_vma(vmi, vma)                                     \
        if (system_supports_mte())                                      \
-               for (vma = tsk->mm->mmap; vma; vma = vma->vm_next)      \
+               for_each_vma(vmi, vma)                                  \
                        if (vma->vm_flags & VM_MTE)
 
 static unsigned long mte_vma_tag_dump_size(struct vm_area_struct *vma)
@@ -65,8 +72,9 @@ Elf_Half elf_core_extra_phdrs(void)
 {
        struct vm_area_struct *vma;
        int vma_count = 0;
+       VMA_ITERATOR(vmi, current->mm, 0);
 
-       for_each_mte_vma(current, vma)
+       for_each_mte_vma(vmi, vma)
                vma_count++;
 
        return vma_count;
@@ -75,8 +83,9 @@ Elf_Half elf_core_extra_phdrs(void)
 int elf_core_write_extra_phdrs(struct coredump_params *cprm, loff_t offset)
 {
        struct vm_area_struct *vma;
+       VMA_ITERATOR(vmi, current->mm, 0);
 
-       for_each_mte_vma(current, vma) {
+       for_each_mte_vma(vmi, vma) {
                struct elf_phdr phdr;
 
                phdr.p_type = PT_ARM_MEMTAG_MTE;
@@ -100,8 +109,9 @@ size_t elf_core_extra_data_size(void)
 {
        struct vm_area_struct *vma;
        size_t data_size = 0;
+       VMA_ITERATOR(vmi, current->mm, 0);
 
-       for_each_mte_vma(current, vma)
+       for_each_mte_vma(vmi, vma)
                data_size += mte_vma_tag_dump_size(vma);
 
        return data_size;
@@ -110,8 +120,9 @@ size_t elf_core_extra_data_size(void)
 int elf_core_write_extra_data(struct coredump_params *cprm)
 {
        struct vm_area_struct *vma;
+       VMA_ITERATOR(vmi, current->mm, 0);
 
-       for_each_mte_vma(current, vma) {
+       for_each_mte_vma(vmi, vma) {
                if (vma->vm_flags & VM_DONTDUMP)
                        continue;