Re: [PATCH V6 17/20] riscv: compat: vdso: Add setup additional pages implementation
On Fri, Feb 25, 2022 at 1:57 AM Palmer Dabbelt wrote:
>
> On Thu, 24 Feb 2022 00:54:07 PST (-0800), guo...@kernel.org wrote:
> > From: Guo Ren
> >
> > Reconstruct __setup_additional_pages() by appending vdso info
> > pointer argument to meet compat_vdso_info requirement. And change
> > vm_special_mapping *dm, *cm initialization into static.
> >
> > Signed-off-by: Guo Ren
> > Signed-off-by: Guo Ren
> > Reviewed-by: Palmer Dabbelt
> > Cc: Arnd Bergmann
> > ---
> > arch/riscv/include/asm/elf.h | 5 ++
> > arch/riscv/include/asm/mmu.h | 1 +
> > arch/riscv/kernel/vdso.c | 103 +++
> > 3 files changed, 74 insertions(+), 35 deletions(-)
> >
> > diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h
> > index 3a4293dc7229..d87d3bcc758d 100644
> > --- a/arch/riscv/include/asm/elf.h
> > +++ b/arch/riscv/include/asm/elf.h
> > @@ -134,5 +134,10 @@ do {if ((ex).e_ident[EI_CLASS] == ELFCLASS32)
> > \
> > typedef compat_ulong_t compat_elf_greg_t;
> > typedef compat_elf_greg_tcompat_elf_gregset_t[ELF_NGREG];
> >
> > +extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> > + int uses_interp);
> > +#define compat_arch_setup_additional_pages \
> > + compat_arch_setup_additional_pages
> > +
> > #endif /* CONFIG_COMPAT */
> > #endif /* _ASM_RISCV_ELF_H */
> > diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> > index 0099dc116168..cedcf8ea3c76 100644
> > --- a/arch/riscv/include/asm/mmu.h
> > +++ b/arch/riscv/include/asm/mmu.h
> > @@ -16,6 +16,7 @@ typedef struct {
> > atomic_long_t id;
> > #endif
> > void *vdso;
> > + void *vdso_info;
> > #ifdef CONFIG_SMP
> > /* A local icache flush is needed before user execution can resume. */
> > cpumask_t icache_stale_mask;
> > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> > index a9436a65161a..f864811aa011 100644
> > --- a/arch/riscv/kernel/vdso.c
> > +++ b/arch/riscv/kernel/vdso.c
> > @@ -23,6 +23,9 @@ struct vdso_data {
> > #endif
> >
> > extern char vdso_start[], vdso_end[];
> > +#ifdef CONFIG_COMPAT
> > +extern char compat_vdso_start[], compat_vdso_end[];
> > +#endif
> >
> > enum vvar_pages {
> > VVAR_DATA_PAGE_OFFSET,
> > @@ -30,6 +33,11 @@ enum vvar_pages {
> > VVAR_NR_PAGES,
> > };
> >
> > +enum rv_vdso_map {
> > + RV_VDSO_MAP_VVAR,
> > + RV_VDSO_MAP_VDSO,
> > +};
> > +
> > #define VVAR_SIZE (VVAR_NR_PAGES << PAGE_SHIFT)
> >
> > /*
> > @@ -52,12 +60,6 @@ struct __vdso_info {
> > struct vm_special_mapping *cm;
> > };
> >
> > -static struct __vdso_info vdso_info __ro_after_init = {
> > - .name = "vdso",
> > - .vdso_code_start = vdso_start,
> > - .vdso_code_end = vdso_end,
> > -};
> > -
> > static int vdso_mremap(const struct vm_special_mapping *sm,
> > struct vm_area_struct *new_vma)
> > {
> > @@ -66,37 +68,33 @@ static int vdso_mremap(const struct vm_special_mapping
> > *sm,
> > return 0;
> > }
> >
> > -static int __init __vdso_init(void)
> > +static void __init __vdso_init(struct __vdso_info *vdso_info)
> > {
> > unsigned int i;
> > struct page **vdso_pagelist;
> > unsigned long pfn;
> >
> > - if (memcmp(vdso_info.vdso_code_start, "\177ELF", 4)) {
> > - pr_err("vDSO is not a valid ELF object!\n");
> > - return -EINVAL;
> > - }
> > + if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> > + panic("vDSO is not a valid ELF object!\n");
> >
> > - vdso_info.vdso_pages = (
> > - vdso_info.vdso_code_end -
> > - vdso_info.vdso_code_start) >>
> > + vdso_info->vdso_pages = (
> > + vdso_info->vdso_code_end -
> > + vdso_info->vdso_code_start) >>
> > PAGE_SHIFT;
> >
> > - vdso_pagelist = kcalloc(vdso_info.vdso_pages,
> > + vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> > sizeof(struct page *),
> > GFP_KERNEL);
> > if (vdso_pagelist == NULL)
> > - return -ENOMEM;
> > + panic("vDSO kcalloc failed!\n");
> >
> > /* Grab the vDSO code pages. */
> > - pfn = sym_to_pfn(vdso_info.vdso_code_start);
> > + pfn = sym_to_pfn(vdso_info->vdso_code_start);
> >
> > - for (i = 0; i < vdso_info.vdso_pages; i++)
> > + for (i = 0; i < vdso_info->vdso_pages; i++)
> > vdso_pagelist[i] = pfn_to_page(pfn + i);
> >
> > - vdso_info.cm->pages = vdso_pagelist;
> > -
> > - return 0;
> > + vdso_info->cm->pages = vdso_pagelist;
> > }
> >
> > #ifdef CONFIG_TIME_NS
> > @@ -116,13 +114,14 @@ int vdso_join_timens(struct task_struct *task, struct
> > time_namespace *ns)
> > {
> > struct mm_struct *mm = task->mm;
> > struct vm_area_struct *vma;
> > + struct __vdso_info
Re: [PATCH V6 17/20] riscv: compat: vdso: Add setup additional pages implementation
On Thu, 24 Feb 2022 00:54:07 PST (-0800), guo...@kernel.org wrote:
From: Guo Ren
Reconstruct __setup_additional_pages() by appending vdso info
pointer argument to meet compat_vdso_info requirement. And change
vm_special_mapping *dm, *cm initialization into static.
Signed-off-by: Guo Ren
Signed-off-by: Guo Ren
Reviewed-by: Palmer Dabbelt
Cc: Arnd Bergmann
---
arch/riscv/include/asm/elf.h | 5 ++
arch/riscv/include/asm/mmu.h | 1 +
arch/riscv/kernel/vdso.c | 103 +++
3 files changed, 74 insertions(+), 35 deletions(-)
diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h
index 3a4293dc7229..d87d3bcc758d 100644
--- a/arch/riscv/include/asm/elf.h
+++ b/arch/riscv/include/asm/elf.h
@@ -134,5 +134,10 @@ do {if ((ex).e_ident[EI_CLASS] == ELFCLASS32)
\
typedef compat_ulong_t compat_elf_greg_t;
typedef compat_elf_greg_t compat_elf_gregset_t[ELF_NGREG];
+extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
+ int uses_interp);
+#define compat_arch_setup_additional_pages \
+ compat_arch_setup_additional_pages
+
#endif /* CONFIG_COMPAT */
#endif /* _ASM_RISCV_ELF_H */
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
index 0099dc116168..cedcf8ea3c76 100644
--- a/arch/riscv/include/asm/mmu.h
+++ b/arch/riscv/include/asm/mmu.h
@@ -16,6 +16,7 @@ typedef struct {
atomic_long_t id;
#endif
void *vdso;
+ void *vdso_info;
#ifdef CONFIG_SMP
/* A local icache flush is needed before user execution can resume. */
cpumask_t icache_stale_mask;
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index a9436a65161a..f864811aa011 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -23,6 +23,9 @@ struct vdso_data {
#endif
extern char vdso_start[], vdso_end[];
+#ifdef CONFIG_COMPAT
+extern char compat_vdso_start[], compat_vdso_end[];
+#endif
enum vvar_pages {
VVAR_DATA_PAGE_OFFSET,
@@ -30,6 +33,11 @@ enum vvar_pages {
VVAR_NR_PAGES,
};
+enum rv_vdso_map {
+ RV_VDSO_MAP_VVAR,
+ RV_VDSO_MAP_VDSO,
+};
+
#define VVAR_SIZE (VVAR_NR_PAGES << PAGE_SHIFT)
/*
@@ -52,12 +60,6 @@ struct __vdso_info {
struct vm_special_mapping *cm;
};
-static struct __vdso_info vdso_info __ro_after_init = {
- .name = "vdso",
- .vdso_code_start = vdso_start,
- .vdso_code_end = vdso_end,
-};
-
static int vdso_mremap(const struct vm_special_mapping *sm,
struct vm_area_struct *new_vma)
{
@@ -66,37 +68,33 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
return 0;
}
-static int __init __vdso_init(void)
+static void __init __vdso_init(struct __vdso_info *vdso_info)
{
unsigned int i;
struct page **vdso_pagelist;
unsigned long pfn;
- if (memcmp(vdso_info.vdso_code_start, "\177ELF", 4)) {
- pr_err("vDSO is not a valid ELF object!\n");
- return -EINVAL;
- }
+ if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
+ panic("vDSO is not a valid ELF object!\n");
- vdso_info.vdso_pages = (
- vdso_info.vdso_code_end -
- vdso_info.vdso_code_start) >>
+ vdso_info->vdso_pages = (
+ vdso_info->vdso_code_end -
+ vdso_info->vdso_code_start) >>
PAGE_SHIFT;
- vdso_pagelist = kcalloc(vdso_info.vdso_pages,
+ vdso_pagelist = kcalloc(vdso_info->vdso_pages,
sizeof(struct page *),
GFP_KERNEL);
if (vdso_pagelist == NULL)
- return -ENOMEM;
+ panic("vDSO kcalloc failed!\n");
/* Grab the vDSO code pages. */
- pfn = sym_to_pfn(vdso_info.vdso_code_start);
+ pfn = sym_to_pfn(vdso_info->vdso_code_start);
- for (i = 0; i < vdso_info.vdso_pages; i++)
+ for (i = 0; i < vdso_info->vdso_pages; i++)
vdso_pagelist[i] = pfn_to_page(pfn + i);
- vdso_info.cm->pages = vdso_pagelist;
-
- return 0;
+ vdso_info->cm->pages = vdso_pagelist;
}
#ifdef CONFIG_TIME_NS
@@ -116,13 +114,14 @@ int vdso_join_timens(struct task_struct *task, struct
time_namespace *ns)
{
struct mm_struct *mm = task->mm;
struct vm_area_struct *vma;
+ struct __vdso_info *vdso_info = mm->context.vdso_info;
mmap_read_lock(mm);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
unsigned long size = vma->vm_end - vma->vm_start;
- if (vma_is_special_mapping(vma, vdso_info.dm))
+ if (vma_is_special_mapping(vma, vdso_info->dm))
zap_page_range(vma, vma->vm_start, size);
}
@@ -187,11 +186,6 @@ static vm_fault_t vvar_fault(const struct
vm_special_mapping *sm,
return vmf_in
