diff mbox series

[v2,08/10] s390/uv: convert uv_convert_owned_from_secure() to uv_convert_from_secure_(folio|pte)()

Message ID 20240412142120.220087-9-david@redhat.com (mailing list archive)
State New, archived
Headers show
Series s390: PG_arch_1+folio cleanups for uv+hugetlb | expand

Commit Message

David Hildenbrand April 12, 2024, 2:21 p.m. UTC 
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.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 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(-)

Comments

Claudio Imbrenda May 7, 2024, 4:26 p.m. UTC | #1 
On Fri, 12 Apr 2024 16:21:18 +0200
David Hildenbrand <david@redhat.com> wrote:

> 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.
> 
> Signed-off-by: David Hildenbrand <david@redhat.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> ---
>  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 97e040617c29..5ffc4828c25a 100644
> --- a/arch/s390/include/asm/pgtable.h
> +++ b/arch/s390/include/asm/pgtable.h
> @@ -1149,7 +1149,7 @@ 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;
>  }
>  
> @@ -1167,7 +1167,7 @@ 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;
>  }
>  
> @@ -1206,7 +1206,7 @@ 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);
diff mbox series

Patch

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 97e040617c29..5ffc4828c25a 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1149,7 +1149,7 @@  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;
 }
 
@@ -1167,7 +1167,7 @@  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;
 }
 
@@ -1206,7 +1206,7 @@  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);