Unverified Commit 3092eb45 authored by Guo Ren's avatar Guo Ren Committed by Palmer Dabbelt
Browse files

riscv: compat: vdso: Add setup additional pages implementation 



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: default avatarGuo Ren <guoren@linux.alibaba.com>
Signed-off-by: default avatarGuo Ren <guoren@kernel.org>
Reviewed-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
Tested-by: default avatarHeiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20220405071314.3225832-18-guoren@kernel.org


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 0715372a

arch/riscv/include/asm/elf.h

+5 −0
Original line number Diff line number Diff line
@@ -130,5 +130,10 @@ 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 */

arch/riscv/include/asm/mmu.h

+1 −0
Original line number Diff line number Diff line
@@ -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;

arch/riscv/kernel/vdso.c

+70 −35
Original line number Diff line number Diff line
@@ -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_insert_pfn(vma, vmf->address, pfn);

}



enum rv_vdso_map {

	RV_VDSO_MAP_VVAR,

	RV_VDSO_MAP_VDSO,

};



static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {

	[RV_VDSO_MAP_VVAR] = {

		.name   = "[vvar]",
@@ -203,25 +197,46 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = { 
	},

};



static struct __vdso_info vdso_info __ro_after_init = {

	.name = "vdso",

	.vdso_code_start = vdso_start,

	.vdso_code_end = vdso_end,

	.dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],

	.cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],

};



#ifdef CONFIG_COMPAT

static struct __vdso_info compat_vdso_info __ro_after_init = {

	.name = "compat_vdso",

	.vdso_code_start = compat_vdso_start,

	.vdso_code_end = compat_vdso_end,

	.dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],

	.cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],

};

#endif



static int __init vdso_init(void)

{

	vdso_info.dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR];

	vdso_info.cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO];

	__vdso_init(&vdso_info);

#ifdef CONFIG_COMPAT

	__vdso_init(&compat_vdso_info);

#endif



	return __vdso_init();

	return 0;

}

arch_initcall(vdso_init);



static int __setup_additional_pages(struct mm_struct *mm,

				    struct linux_binprm *bprm,

				    int uses_interp)

				    int uses_interp,

				    struct __vdso_info *vdso_info)

{

	unsigned long vdso_base, vdso_text_len, vdso_mapping_len;

	void *ret;



	BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);



	vdso_text_len = vdso_info.vdso_pages << PAGE_SHIFT;

	vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;

	/* Be sure to map the data page */

	vdso_mapping_len = vdso_text_len + VVAR_SIZE;
@@ -232,16 +247,18 @@ static int __setup_additional_pages(struct mm_struct *mm, 
	}



	ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,

		(VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info.dm);

		(VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);

	if (IS_ERR(ret))

		goto up_fail;



	vdso_base += VVAR_SIZE;

	mm->context.vdso = (void *)vdso_base;

	mm->context.vdso_info = (void *)vdso_info;



	ret =

	   _install_special_mapping(mm, vdso_base, vdso_text_len,

		(VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),

		vdso_info.cm);

		vdso_info->cm);



	if (IS_ERR(ret))

		goto up_fail;
@@ -253,6 +270,24 @@ static int __setup_additional_pages(struct mm_struct *mm, 
	return PTR_ERR(ret);

}



#ifdef CONFIG_COMPAT

int compat_arch_setup_additional_pages(struct linux_binprm *bprm,

				       int uses_interp)

{

	struct mm_struct *mm = current->mm;

	int ret;



	if (mmap_write_lock_killable(mm))

		return -EINTR;



	ret = __setup_additional_pages(mm, bprm, uses_interp,

							&compat_vdso_info);

	mmap_write_unlock(mm);



	return ret;

}

#endif



int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)

{

	struct mm_struct *mm = current->mm;
@@ -261,7 +296,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 
	if (mmap_write_lock_killable(mm))

		return -EINTR;



	ret = __setup_additional_pages(mm, bprm, uses_interp);

	ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);

	mmap_write_unlock(mm);



	return ret;