diff options
| author | Claudio Imbrenda <imbrenda@linux.ibm.com> | 2021-09-20 16:24:54 +0300 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2021-10-27 08:55:53 +0300 |
| commit | 380d97bd02fca7b9b41aec2d1c767874d602bc78 (patch) | |
| tree | 8e9f822ec608744ebcb9f4e5ddb293936e59393a /arch/s390/include/asm | |
| parent | 85f517b29418158d3e6e90c3f0fc01b306d2f1a1 (diff) | |
| download | linux-380d97bd02fca7b9b41aec2d1c767874d602bc78.tar.xz | |
KVM: s390: pv: properly handle page flags for protected guests
Introduce variants of the convert and destroy page functions that also
clear the PG_arch_1 bit used to mark them as secure pages.
The PG_arch_1 flag is always allowed to overindicate; using the new
functions introduced here allows to reduce the extent of overindication
and thus improve performance.
These new functions can only be called on pages for which a reference
is already being held.
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Link: https://lore.kernel.org/r/20210920132502.36111-7-imbrenda@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/include/asm')
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 9 | ||||
| -rw-r--r-- | arch/s390/include/asm/uv.h | 10 |
2 files changed, 14 insertions, 5 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index b61426c9ef17..e43416950245 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1074,8 +1074,9 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, pte_t res; 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_from_secure(pte_val(res) & PAGE_MASK); + uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); return res; } @@ -1091,8 +1092,9 @@ static inline pte_t ptep_clear_flush(struct vm_area_struct *vma, pte_t res; 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_from_secure(pte_val(res) & PAGE_MASK); + uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); return res; } @@ -1116,8 +1118,9 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, } else { 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_from_secure(pte_val(res) & PAGE_MASK); + uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); return res; } diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index 9ab1914c5b95..72d3e49c2860 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h @@ -356,8 +356,9 @@ static inline int is_prot_virt_host(void) } int gmap_make_secure(struct gmap *gmap, unsigned long gaddr, void *uvcb); -int uv_destroy_page(unsigned long paddr); +int uv_destroy_owned_page(unsigned long paddr); int uv_convert_from_secure(unsigned long paddr); +int uv_convert_owned_from_secure(unsigned long paddr); int gmap_convert_to_secure(struct gmap *gmap, unsigned long gaddr); void setup_uv(void); @@ -365,7 +366,7 @@ void setup_uv(void); #define is_prot_virt_host() 0 static inline void setup_uv(void) {} -static inline int uv_destroy_page(unsigned long paddr) +static inline int uv_destroy_owned_page(unsigned long paddr) { return 0; } @@ -374,6 +375,11 @@ static inline int uv_convert_from_secure(unsigned long paddr) { return 0; } + +static inline int uv_convert_owned_from_secure(unsigned long paddr) +{ + return 0; +} #endif #endif /* _ASM_S390_UV_H */ |