From mboxrd@z Thu Jan 1 00:00:00 1970 From: Janosch Frank Subject: [RFC/PATCH v2 04/22] s390/mm: Add gmap pmd invalidation and clearing Date: Wed, 13 Dec 2017 13:53:15 +0100 Message-ID: <1513169613-13509-5-git-send-email-frankja@linux.vnet.ibm.com> References: <1513169613-13509-1-git-send-email-frankja@linux.vnet.ibm.com> Return-path: In-Reply-To: <1513169613-13509-1-git-send-email-frankja@linux.vnet.ibm.com> Sender: kvm-owner@vger.kernel.org List-Archive: List-Post: To: kvm@vger.kernel.org Cc: schwidefsky@de.ibm.com, borntraeger@de.ibm.com, david@redhat.com, dominik.dingel@gmail.com, linux-s390@vger.kernel.org List-ID: If the host invalidates a pmd, we also have to invalidate the corresponding gmap pmds, as well as flush them from the TLB. This is necessary, as we don't share the pmd tables between host and guest as we do with ptes. The clearing part of these three new functions sets a guest pmd entry to _SEGMENT_ENTRY_EMPTY, so the guest will fault on it and we will re-link it. Flushing the gmap is not necessary in the host's lazy local and csp cases. Both purge the TLB completely. Signed-off-by: Janosch Frank Reviewed-by: Martin Schwidefsky --- arch/s390/include/asm/pgtable.h | 6 ++- arch/s390/mm/gmap.c | 114 ++++++++++++++++++++++++++++++++++++++++ arch/s390/mm/pgtable.c | 17 ++++-- 3 files changed, 133 insertions(+), 4 deletions(-) diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index ba3840c..647c300 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -272,7 +272,7 @@ static inline int is_module_addr(void *addr) #define _SEGMENT_ENTRY_BITS 0xfffffffffffffe33UL #define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL #define _SEGMENT_ENTRY_HARDWARE_BITS 0xfffffffffffffe30UL -#define _SEGMENT_ENTRY_HARDWARE_BITS_LARGE 0xfffffffffff00730UL +#define _SEGMENT_ENTRY_HARDWARE_BITS_LARGE 0xfffffffffff00730UL #define _SEGMENT_ENTRY_ORIGIN_LARGE ~0xfffffUL /* large page address */ #define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* page table origin */ #define _SEGMENT_ENTRY_PROTECT 0x200 /* segment protection bit */ @@ -1120,6 +1120,10 @@ int set_pgste_bits(struct mm_struct *mm, unsigned long addr, int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep); int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc, unsigned long *oldpte, unsigned long *oldpgste); +void gmap_pmdp_csp(struct mm_struct *mm, unsigned long vmaddr); +void gmap_pmdp_invalidate(struct mm_struct *mm, unsigned long vmaddr); +void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr); +void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr); /* * Certain architectures need to do special things when PTEs diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index ff7fe24..aceaeb5 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -2257,6 +2257,120 @@ void pmdp_notify(struct mm_struct *mm, unsigned long vmaddr) } EXPORT_SYMBOL_GPL(pmdp_notify); +static void gmap_pmdp_clear(struct mm_struct *mm, unsigned long vmaddr, + int purge) +{ + pmd_t *pmdp; + struct gmap *gmap; + + rcu_read_lock(); + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { + spin_lock(&gmap->guest_table_lock); + pmdp = (pmd_t *)radix_tree_delete(&gmap->host_to_guest, + vmaddr >> PMD_SHIFT); + if (pmdp) { + if (purge) + __pmdp_csp(pmdp); + pmd_val(*pmdp) = _SEGMENT_ENTRY_EMPTY; + } + spin_unlock(&gmap->guest_table_lock); + } + rcu_read_unlock(); +} + +/** + * gmap_pmdp_invalidate - invalidate all affected guest pmd entries without + * flushing + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_invalidate(struct mm_struct *mm, unsigned long vmaddr) +{ + gmap_pmdp_clear(mm, vmaddr, 0); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_invalidate); + +/** + * gmap_pmdp_csp - csp all affected guest pmd entries + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_csp(struct mm_struct *mm, unsigned long vmaddr) +{ + gmap_pmdp_clear(mm, vmaddr, 1); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_csp); + +/** + * gmap_pmdp_idte_local - invalidate and clear a guest pmd entry + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr) +{ + unsigned long *entry, gaddr; + struct gmap *gmap; + pmd_t *pmdp; + + rcu_read_lock(); + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { + spin_lock(&gmap->guest_table_lock); + entry = radix_tree_delete(&gmap->host_to_guest, + vmaddr >> PMD_SHIFT); + if (entry) { + pmdp = (pmd_t *)entry; + gaddr = __gmap_segment_gaddr(entry); + if (MACHINE_HAS_TLB_GUEST) + __pmdp_idte(gaddr, pmdp, + IDTE_GUEST_ASCE, + gmap->asce, IDTE_LOCAL); + else if (MACHINE_HAS_IDTE) + __pmdp_idte(gaddr, pmdp, 0, 0, + IDTE_LOCAL); + *entry = _SEGMENT_ENTRY_EMPTY; + } + spin_unlock(&gmap->guest_table_lock); + } + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_idte_local); + +/** + * gmap_pmdp_idte_global - invalidate and clear a guest pmd entry + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr) +{ + unsigned long *entry, gaddr; + struct gmap *gmap; + pmd_t *pmdp; + + rcu_read_lock(); + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { + spin_lock(&gmap->guest_table_lock); + entry = radix_tree_delete(&gmap->host_to_guest, + vmaddr >> PMD_SHIFT); + if (entry) { + pmdp = (pmd_t *)entry; + gaddr = __gmap_segment_gaddr(entry); + if (MACHINE_HAS_TLB_GUEST) + __pmdp_idte(gaddr, pmdp, + IDTE_GUEST_ASCE, + gmap->asce, IDTE_GLOBAL); + else if (MACHINE_HAS_IDTE) + __pmdp_idte(gaddr, pmdp, 0, 0, + IDTE_GLOBAL); + else + __pmdp_csp(pmdp); + *entry = _SEGMENT_ENTRY_EMPTY; + } + spin_unlock(&gmap->guest_table_lock); + } + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_idte_global); + static inline void thp_split_mm(struct mm_struct *mm) { #ifdef CONFIG_TRANSPARENT_HUGEPAGE diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index a6cc540..e690879 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -347,18 +347,27 @@ static inline void pmdp_idte_local(struct mm_struct *mm, mm->context.asce, IDTE_LOCAL); else __pmdp_idte(addr, pmdp, 0, 0, IDTE_LOCAL); + if (mm_has_pgste(mm)) + gmap_pmdp_idte_local(mm, addr); } static inline void pmdp_idte_global(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp) { - if (MACHINE_HAS_TLB_GUEST) + if (MACHINE_HAS_TLB_GUEST) { __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE, mm->context.asce, IDTE_GLOBAL); - else if (MACHINE_HAS_IDTE) + if (mm_has_pgste(mm)) + gmap_pmdp_idte_global(mm, addr); + } else if (MACHINE_HAS_IDTE) { __pmdp_idte(addr, pmdp, 0, 0, IDTE_GLOBAL); - else + if (mm_has_pgste(mm)) + gmap_pmdp_idte_global(mm, addr); + } else { __pmdp_csp(pmdp); + if (mm_has_pgste(mm)) + gmap_pmdp_csp(mm, addr); + } } static inline pmd_t pmdp_flush_direct(struct mm_struct *mm, @@ -392,6 +401,8 @@ static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm, cpumask_of(smp_processor_id()))) { pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID; mm->context.flush_mm = 1; + if (mm_has_pgste(mm)) + gmap_pmdp_invalidate(mm, addr); } else { pmdp_idte_global(mm, addr, pmdp); } -- 2.7.4