Bikeshedding alarm, please see below. On 09/09/2019 20:12, Pavel Tatashin wrote: > 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: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> > --- > arch/arm64/include/asm/trans_pgd.h | 24 ++++++++++++++++++++++-- > arch/arm64/kernel/hibernate.c | 12 +++++++++++- > arch/arm64/mm/trans_pgd.c | 17 +++++++++++------ > 3 files changed, 44 insertions(+), 9 deletions(-) > > diff --git a/arch/arm64/include/asm/trans_pgd.h b/arch/arm64/include/asm/trans_pgd.h > index c7b5402b7d87..53f67ec84cdc 100644 > --- a/arch/arm64/include/asm/trans_pgd.h > +++ b/arch/arm64/include/asm/trans_pgd.h > @@ -11,10 +11,30 @@ > #include <linux/bits.h> > #include <asm/pgtable-types.h> > > +/* > + * trans_alloc_page > + * - Allocator that should return exactly one zeroed page, if this > + * allocator fails, trans_pgd returns -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); > +/* > + * Add map entry to trans_pgd for a base-size page at PTE level. > + * page: page to be mapped. > + * dst_addr: new VA address for the pages > + * pgprot: protection for the page. For consistency please describe all function parameters. From my experience function parameter description is normally done in the C-file that implements the logic. Don't ask me why. > + */ > +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 */ > diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c > index 94ede33bd777..9b75b680ab70 100644 > --- a/arch/arm64/kernel/hibernate.c > +++ b/arch/arm64/kernel/hibernate.c > @@ -179,6 +179,12 @@ int arch_hibernation_header_restore(void *addr) > } > EXPORT_SYMBOL(arch_hibernation_header_restore); > > +static void * > +hibernate_page_alloc(void *arg) AFAICS no new line needed here. > +{ > + 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 > @@ -195,6 +201,10 @@ 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, > + }; New line between end of struct and other variables. With these changes: Reviewed-by: Matthias Brugger <mbrugger@xxxxxxxx> > void *page = (void *)get_safe_page(GFP_ATOMIC); > pgd_t *trans_pgd; > int rc; > @@ -209,7 +219,7 @@ 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; > diff --git a/arch/arm64/mm/trans_pgd.c b/arch/arm64/mm/trans_pgd.c > index 5ac712b92439..7521d558a0b9 100644 > --- a/arch/arm64/mm/trans_pgd.c > +++ b/arch/arm64/mm/trans_pgd.c > @@ -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); > @@ -180,8 +185,8 @@ 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) > +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; > pud_t *pudp; > @@ -190,7 +195,7 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, unsigned long dst_addr, > > pgdp = pgd_offset_raw(trans_pgd, dst_addr); > if (pgd_none(READ_ONCE(*pgdp))) { > - pudp = (void *)get_safe_page(GFP_ATOMIC); > + pudp = trans_alloc(info); > if (!pudp) > return -ENOMEM; > pgd_populate(&init_mm, pgdp, pudp); > @@ -198,7 +203,7 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, unsigned long dst_addr, > > pudp = pud_offset(pgdp, 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); > @@ -206,14 +211,14 @@ int trans_pgd_map_page(pgd_t *trans_pgd, void *page, unsigned long dst_addr, > > 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; > } > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec