Let's do the same as we did for uv_destroy_(folio|pte)() and have the following variants: (1) uv_convert_from_secure(): "low level" helper that operates on paddr and does not mess with folios. (2) uv_convert_from_secure_folio(): Consumes a folio to which we hold a reference. (3) uv_convert_from_secure_pte(): Consumes a PTE that holds a reference through the mapping. Unfortunately we need uv_convert_from_secure_pte(), because pfn_folio() and friends are not available in pgtable.h. Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> --- arch/s390/include/asm/pgtable.h | 6 +++--- arch/s390/include/asm/uv.h | 4 ++-- arch/s390/kernel/uv.c | 18 +++++++++++++----- 3 files changed, 18 insertions(+), 10 deletions(-) diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index f65db37917f2..928282bacfc7 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1165,7 +1165,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, res = ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID)); /* At this point the reference through the mapping is still present */ if (mm_is_protected(mm) && pte_present(res)) - uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); + uv_convert_from_secure_pte(res); return res; } @@ -1183,7 +1183,7 @@ static inline pte_t ptep_clear_flush(struct vm_area_struct *vma, res = ptep_xchg_direct(vma->vm_mm, addr, ptep, __pte(_PAGE_INVALID)); /* At this point the reference through the mapping is still present */ if (mm_is_protected(vma->vm_mm) && pte_present(res)) - uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); + uv_convert_from_secure_pte(res); return res; } @@ -1222,7 +1222,7 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, * if this is not a mm teardown, the slower export is used as * fallback instead. */ - uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); + uv_convert_from_secure_pte(res); return res; } diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index a1bef30066ef..0679445cac0b 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h @@ -485,7 +485,7 @@ int gmap_make_secure(struct gmap *gmap, unsigned long gaddr, void *uvcb); int gmap_destroy_page(struct gmap *gmap, unsigned long gaddr); int uv_destroy_folio(struct folio *folio); int uv_destroy_pte(pte_t pte); -int uv_convert_owned_from_secure(unsigned long paddr); +int uv_convert_from_secure_pte(pte_t pte); int gmap_convert_to_secure(struct gmap *gmap, unsigned long gaddr); void setup_uv(void); @@ -508,7 +508,7 @@ static inline int uv_destroy_pte(pte_t pte) return 0; } -static inline int uv_convert_owned_from_secure(unsigned long paddr) +static inline int uv_convert_from_secure_pte(pte_t pte) { return 0; } diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c index 61c1ce51c883..b456066d72da 100644 --- a/arch/s390/kernel/uv.c +++ b/arch/s390/kernel/uv.c @@ -178,11 +178,10 @@ static int uv_convert_from_secure(unsigned long paddr) } /* - * The caller must already hold a reference to the page + * The caller must already hold a reference to the folio. */ -int uv_convert_owned_from_secure(unsigned long paddr) +static int uv_convert_from_secure_folio(struct folio *folio) { - struct folio *folio = phys_to_folio(paddr); int rc; /* See gmap_make_secure(): large folios cannot be secure */ @@ -190,13 +189,22 @@ int uv_convert_owned_from_secure(unsigned long paddr) return 0; folio_get(folio); - rc = uv_convert_from_secure(paddr); + rc = uv_convert_from_secure(folio_to_phys(folio)); if (!rc) clear_bit(PG_arch_1, &folio->flags); folio_put(folio); return rc; } +/* + * The present PTE still indirectly holds a folio reference through the mapping. + */ +int uv_convert_from_secure_pte(pte_t pte) +{ + VM_WARN_ON(!pte_present(pte)); + return uv_convert_from_secure_folio(pfn_folio(pte_pfn(pte))); +} + /* * Calculate the expected ref_count for a folio that would otherwise have no * further pins. This was cribbed from similar functions in other places in @@ -481,7 +489,7 @@ int gmap_destroy_page(struct gmap *gmap, unsigned long gaddr) * we instead try to export the page. */ if (rc) - rc = uv_convert_owned_from_secure(page_to_phys(page)); + rc = uv_convert_from_secure_folio(folio); folio_put(folio); out: mmap_read_unlock(gmap->mm); -- 2.45.0