Commit 50f53fb7 authored by Pavel Tatashin's avatar Pavel Tatashin Committed by Will Deacon
Browse files

arm64: trans_pgd: make trans_pgd_map_page generic 



kexec is going to use a different allocator, so make
trans_pgd_map_page to accept allocator as an argument, and also
kexec is going to use a different map protection, so also pass
it via argument.

Signed-off-by: default avatarPavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: default avatarMatthias Brugger <mbrugger@suse.com>
Link: https://lore.kernel.org/r/20210125191923.1060122-5-pasha.tatashin@soleen.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 072e3d96

arch/arm64/include/asm/trans_pgd.h

+17 −2
Original line number Diff line number Diff line
@@ -12,10 +12,25 @@ 
#include <linux/types.h>

#include <asm/pgtable-types.h>



/*

 * trans_alloc_page

 *	- Allocator that should return exactly one zeroed page, if this

 *	  allocator fails, trans_pgd_create_copy() and trans_pgd_map_page()

 *	  return -ENOMEM error.

 *

 * trans_alloc_arg

 *	- Passed to trans_alloc_page as an argument

 */



struct trans_pgd_info {

	void * (*trans_alloc_page)(void *arg);

	void *trans_alloc_arg;

};



int trans_pgd_create_copy(pgd_t **dst_pgdp, unsigned long start,

			  unsigned long end);



int trans_pgd_map_page(pgd_t *trans_pgd, void *page, unsigned long dst_addr,

		       pgprot_t pgprot);

int trans_pgd_map_page(struct trans_pgd_info *info, pgd_t *trans_pgd,

		       void *page, unsigned long dst_addr, pgprot_t pgprot);



#endif /* _ASM_TRANS_TABLE_H */

arch/arm64/kernel/hibernate.c

+11 −1
Original line number Diff line number Diff line
@@ -176,6 +176,11 @@ int arch_hibernation_header_restore(void *addr) 
}

EXPORT_SYMBOL(arch_hibernation_header_restore);



static void *hibernate_page_alloc(void *arg)

{

	return (void *)get_safe_page((gfp_t)(unsigned long)arg);

}



/*

 * Copies length bytes, starting at src_start into an new page,

 * perform cache maintenance, then maps it at the specified address low
@@ -192,6 +197,11 @@ static int create_safe_exec_page(void *src_start, size_t length, 
				 unsigned long dst_addr,

				 phys_addr_t *phys_dst_addr)

{

	struct trans_pgd_info trans_info = {

		.trans_alloc_page	= hibernate_page_alloc,

		.trans_alloc_arg	= (void *)GFP_ATOMIC,

	};



	void *page = (void *)get_safe_page(GFP_ATOMIC);

	pgd_t *trans_pgd;

	int rc;
@@ -206,7 +216,7 @@ static int create_safe_exec_page(void *src_start, size_t length, 
	if (!trans_pgd)

		return -ENOMEM;



	rc = trans_pgd_map_page(trans_pgd, page, dst_addr,

	rc = trans_pgd_map_page(&trans_info, trans_pgd, page, dst_addr,

				PAGE_KERNEL_EXEC);

	if (rc)

		return rc;

arch/arm64/mm/trans_pgd.c

+22 −8
Original line number Diff line number Diff line
@@ -25,6 +25,11 @@ 
#include <linux/mm.h>

#include <linux/mmzone.h>



static void *trans_alloc(struct trans_pgd_info *info)

{

	return info->trans_alloc_page(info->trans_alloc_arg);

}



static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr)

{

	pte_t pte = READ_ONCE(*src_ptep);
@@ -201,9 +206,18 @@ int trans_pgd_create_copy(pgd_t **dst_pgdp, unsigned long start, 
	return rc;

}



int trans_pgd_map_page(pgd_t *trans_pgd, void *page,

		       unsigned long dst_addr,

		       pgprot_t pgprot)

/*

 * Add map entry to trans_pgd for a base-size page at PTE level.

 * info:	contains allocator and its argument

 * trans_pgd:	page table in which new map is added.

 * page:	page to be mapped.

 * dst_addr:	new VA address for the page

 * pgprot:	protection for the page.

 *

 * Returns 0 on success, and -ENOMEM on failure.

 */

int trans_pgd_map_page(struct trans_pgd_info *info, pgd_t *trans_pgd,

		       void *page, unsigned long dst_addr, pgprot_t pgprot)

{

	pgd_t *pgdp;

	p4d_t *p4dp;
@@ -213,7 +227,7 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, 


	pgdp = pgd_offset_pgd(trans_pgd, dst_addr);

	if (pgd_none(READ_ONCE(*pgdp))) {

		p4dp = (void *)get_safe_page(GFP_ATOMIC);

		p4dp = trans_alloc(info);

		if (!pgdp)

			return -ENOMEM;

		pgd_populate(&init_mm, pgdp, p4dp);
@@ -221,7 +235,7 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, 


	p4dp = p4d_offset(pgdp, dst_addr);

	if (p4d_none(READ_ONCE(*p4dp))) {

		pudp = (void *)get_safe_page(GFP_ATOMIC);

		pudp = trans_alloc(info);

		if (!pudp)

			return -ENOMEM;

		p4d_populate(&init_mm, p4dp, pudp);
@@ -229,7 +243,7 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, 


	pudp = pud_offset(p4dp, dst_addr);

	if (pud_none(READ_ONCE(*pudp))) {

		pmdp = (void *)get_safe_page(GFP_ATOMIC);

		pmdp = trans_alloc(info);

		if (!pmdp)

			return -ENOMEM;

		pud_populate(&init_mm, pudp, pmdp);
@@ -237,14 +251,14 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, 


	pmdp = pmd_offset(pudp, dst_addr);

	if (pmd_none(READ_ONCE(*pmdp))) {

		ptep = (void *)get_safe_page(GFP_ATOMIC);

		ptep = trans_alloc(info);

		if (!ptep)

			return -ENOMEM;

		pmd_populate_kernel(&init_mm, pmdp, ptep);

	}



	ptep = pte_offset_kernel(pmdp, dst_addr);

	set_pte(ptep, pfn_pte(virt_to_pfn(page), PAGE_KERNEL_EXEC));

	set_pte(ptep, pfn_pte(virt_to_pfn(page), pgprot));



	return 0;

}