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-rw-r--r--arch/s390/kvm/gaccess.c387
1 files changed, 320 insertions, 67 deletions
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 66938d283b77..54200208bf24 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -8,6 +8,7 @@
#include <linux/vmalloc.h>
#include <linux/err.h>
#include <asm/pgtable.h>
+#include <asm/gmap.h>
#include "kvm-s390.h"
#include "gaccess.h"
#include <asm/switch_to.h>
@@ -476,18 +477,73 @@ enum {
FSI_FETCH = 2 /* Exception was due to fetch operation */
};
-static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce,
- ar_t ar, enum gacc_mode mode)
+enum prot_type {
+ PROT_TYPE_LA = 0,
+ PROT_TYPE_KEYC = 1,
+ PROT_TYPE_ALC = 2,
+ PROT_TYPE_DAT = 3,
+};
+
+static int trans_exc(struct kvm_vcpu *vcpu, int code, unsigned long gva,
+ ar_t ar, enum gacc_mode mode, enum prot_type prot)
{
- int rc;
- struct psw_bits psw = psw_bits(vcpu->arch.sie_block->gpsw);
struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm;
- struct trans_exc_code_bits *tec_bits;
+ struct trans_exc_code_bits *tec;
memset(pgm, 0, sizeof(*pgm));
- tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
- tec_bits->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH;
- tec_bits->as = psw.as;
+ pgm->code = code;
+ tec = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
+
+ switch (code) {
+ case PGM_ASCE_TYPE:
+ case PGM_PAGE_TRANSLATION:
+ case PGM_REGION_FIRST_TRANS:
+ case PGM_REGION_SECOND_TRANS:
+ case PGM_REGION_THIRD_TRANS:
+ case PGM_SEGMENT_TRANSLATION:
+ /*
+ * op_access_id only applies to MOVE_PAGE -> set bit 61
+ * exc_access_id has to be set to 0 for some instructions. Both
+ * cases have to be handled by the caller. We can always store
+ * exc_access_id, as it is undefined for non-ar cases.
+ */
+ tec->addr = gva >> PAGE_SHIFT;
+ tec->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH;
+ tec->as = psw_bits(vcpu->arch.sie_block->gpsw).as;
+ /* FALL THROUGH */
+ case PGM_ALEN_TRANSLATION:
+ case PGM_ALE_SEQUENCE:
+ case PGM_ASTE_VALIDITY:
+ case PGM_ASTE_SEQUENCE:
+ case PGM_EXTENDED_AUTHORITY:
+ pgm->exc_access_id = ar;
+ break;
+ case PGM_PROTECTION:
+ switch (prot) {
+ case PROT_TYPE_ALC:
+ tec->b60 = 1;
+ /* FALL THROUGH */
+ case PROT_TYPE_DAT:
+ tec->b61 = 1;
+ tec->addr = gva >> PAGE_SHIFT;
+ tec->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH;
+ tec->as = psw_bits(vcpu->arch.sie_block->gpsw).as;
+ /* exc_access_id is undefined for most cases */
+ pgm->exc_access_id = ar;
+ break;
+ default: /* LA and KEYC set b61 to 0, other params undefined */
+ break;
+ }
+ break;
+ }
+ return code;
+}
+
+static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce,
+ unsigned long ga, ar_t ar, enum gacc_mode mode)
+{
+ int rc;
+ struct psw_bits psw = psw_bits(vcpu->arch.sie_block->gpsw);
if (!psw.t) {
asce->val = 0;
@@ -510,21 +566,8 @@ static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce,
return 0;
case PSW_AS_ACCREG:
rc = ar_translation(vcpu, asce, ar, mode);
- switch (rc) {
- case PGM_ALEN_TRANSLATION:
- case PGM_ALE_SEQUENCE:
- case PGM_ASTE_VALIDITY:
- case PGM_ASTE_SEQUENCE:
- case PGM_EXTENDED_AUTHORITY:
- vcpu->arch.pgm.exc_access_id = ar;
- break;
- case PGM_PROTECTION:
- tec_bits->b60 = 1;
- tec_bits->b61 = 1;
- break;
- }
if (rc > 0)
- pgm->code = rc;
+ return trans_exc(vcpu, rc, ga, ar, mode, PROT_TYPE_ALC);
return rc;
}
return 0;
@@ -729,40 +772,31 @@ static int low_address_protection_enabled(struct kvm_vcpu *vcpu,
return 1;
}
-static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga,
+static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar,
unsigned long *pages, unsigned long nr_pages,
const union asce asce, enum gacc_mode mode)
{
- struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm;
psw_t *psw = &vcpu->arch.sie_block->gpsw;
- struct trans_exc_code_bits *tec_bits;
- int lap_enabled, rc;
+ int lap_enabled, rc = 0;
- tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
lap_enabled = low_address_protection_enabled(vcpu, asce);
while (nr_pages) {
ga = kvm_s390_logical_to_effective(vcpu, ga);
- tec_bits->addr = ga >> PAGE_SHIFT;
- if (mode == GACC_STORE && lap_enabled && is_low_address(ga)) {
- pgm->code = PGM_PROTECTION;
- return pgm->code;
- }
+ if (mode == GACC_STORE && lap_enabled && is_low_address(ga))
+ return trans_exc(vcpu, PGM_PROTECTION, ga, ar, mode,
+ PROT_TYPE_LA);
ga &= PAGE_MASK;
if (psw_bits(*psw).t) {
rc = guest_translate(vcpu, ga, pages, asce, mode);
if (rc < 0)
return rc;
- if (rc == PGM_PROTECTION)
- tec_bits->b61 = 1;
- if (rc)
- pgm->code = rc;
} else {
*pages = kvm_s390_real_to_abs(vcpu, ga);
if (kvm_is_error_gpa(vcpu->kvm, *pages))
- pgm->code = PGM_ADDRESSING;
+ rc = PGM_ADDRESSING;
}
- if (pgm->code)
- return pgm->code;
+ if (rc)
+ return trans_exc(vcpu, rc, ga, ar, mode, PROT_TYPE_DAT);
ga += PAGE_SIZE;
pages++;
nr_pages--;
@@ -783,7 +817,8 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar, void *data,
if (!len)
return 0;
- rc = get_vcpu_asce(vcpu, &asce, ar, mode);
+ ga = kvm_s390_logical_to_effective(vcpu, ga);
+ rc = get_vcpu_asce(vcpu, &asce, ga, ar, mode);
if (rc)
return rc;
nr_pages = (((ga & ~PAGE_MASK) + len - 1) >> PAGE_SHIFT) + 1;
@@ -795,7 +830,7 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar, void *data,
need_ipte_lock = psw_bits(*psw).t && !asce.r;
if (need_ipte_lock)
ipte_lock(vcpu);
- rc = guest_page_range(vcpu, ga, pages, nr_pages, asce, mode);
+ rc = guest_page_range(vcpu, ga, ar, pages, nr_pages, asce, mode);
for (idx = 0; idx < nr_pages && !rc; idx++) {
gpa = *(pages + idx) + (ga & ~PAGE_MASK);
_len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len);
@@ -846,37 +881,28 @@ int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra,
int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva, ar_t ar,
unsigned long *gpa, enum gacc_mode mode)
{
- struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm;
psw_t *psw = &vcpu->arch.sie_block->gpsw;
- struct trans_exc_code_bits *tec;
union asce asce;
int rc;
gva = kvm_s390_logical_to_effective(vcpu, gva);
- tec = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
- rc = get_vcpu_asce(vcpu, &asce, ar, mode);
- tec->addr = gva >> PAGE_SHIFT;
+ rc = get_vcpu_asce(vcpu, &asce, gva, ar, mode);
if (rc)
return rc;
if (is_low_address(gva) && low_address_protection_enabled(vcpu, asce)) {
- if (mode == GACC_STORE) {
- rc = pgm->code = PGM_PROTECTION;
- return rc;
- }
+ if (mode == GACC_STORE)
+ return trans_exc(vcpu, PGM_PROTECTION, gva, 0,
+ mode, PROT_TYPE_LA);
}
if (psw_bits(*psw).t && !asce.r) { /* Use DAT? */
rc = guest_translate(vcpu, gva, gpa, asce, mode);
- if (rc > 0) {
- if (rc == PGM_PROTECTION)
- tec->b61 = 1;
- pgm->code = rc;
- }
+ if (rc > 0)
+ return trans_exc(vcpu, rc, gva, 0, mode, PROT_TYPE_DAT);
} else {
- rc = 0;
*gpa = kvm_s390_real_to_abs(vcpu, gva);
if (kvm_is_error_gpa(vcpu->kvm, *gpa))
- rc = pgm->code = PGM_ADDRESSING;
+ return trans_exc(vcpu, rc, gva, PGM_ADDRESSING, mode, 0);
}
return rc;
@@ -915,20 +941,247 @@ int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, ar_t ar,
*/
int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra)
{
- struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm;
- psw_t *psw = &vcpu->arch.sie_block->gpsw;
- struct trans_exc_code_bits *tec_bits;
union ctlreg0 ctlreg0 = {.val = vcpu->arch.sie_block->gcr[0]};
if (!ctlreg0.lap || !is_low_address(gra))
return 0;
+ return trans_exc(vcpu, PGM_PROTECTION, gra, 0, GACC_STORE, PROT_TYPE_LA);
+}
- memset(pgm, 0, sizeof(*pgm));
- tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
- tec_bits->fsi = FSI_STORE;
- tec_bits->as = psw_bits(*psw).as;
- tec_bits->addr = gra >> PAGE_SHIFT;
- pgm->code = PGM_PROTECTION;
+/**
+ * kvm_s390_shadow_tables - walk the guest page table and create shadow tables
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @pgt: pointer to the page table address result
+ * @fake: pgt references contiguous guest memory block, not a pgtable
+ */
+static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
+ unsigned long *pgt, int *dat_protection,
+ int *fake)
+{
+ struct gmap *parent;
+ union asce asce;
+ union vaddress vaddr;
+ unsigned long ptr;
+ int rc;
+
+ *fake = 0;
+ *dat_protection = 0;
+ parent = sg->parent;
+ vaddr.addr = saddr;
+ asce.val = sg->orig_asce;
+ ptr = asce.origin * 4096;
+ if (asce.r) {
+ *fake = 1;
+ asce.dt = ASCE_TYPE_REGION1;
+ }
+ switch (asce.dt) {
+ case ASCE_TYPE_REGION1:
+ if (vaddr.rfx01 > asce.tl && !asce.r)
+ return PGM_REGION_FIRST_TRANS;
+ break;
+ case ASCE_TYPE_REGION2:
+ if (vaddr.rfx)
+ return PGM_ASCE_TYPE;
+ if (vaddr.rsx01 > asce.tl)
+ return PGM_REGION_SECOND_TRANS;
+ break;
+ case ASCE_TYPE_REGION3:
+ if (vaddr.rfx || vaddr.rsx)
+ return PGM_ASCE_TYPE;
+ if (vaddr.rtx01 > asce.tl)
+ return PGM_REGION_THIRD_TRANS;
+ break;
+ case ASCE_TYPE_SEGMENT:
+ if (vaddr.rfx || vaddr.rsx || vaddr.rtx)
+ return PGM_ASCE_TYPE;
+ if (vaddr.sx01 > asce.tl)
+ return PGM_SEGMENT_TRANSLATION;
+ break;
+ }
+
+ switch (asce.dt) {
+ case ASCE_TYPE_REGION1: {
+ union region1_table_entry rfte;
- return pgm->code;
+ if (*fake) {
+ /* offset in 16EB guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.rsx << 53UL);
+ rfte.val = ptr;
+ goto shadow_r2t;
+ }
+ rc = gmap_read_table(parent, ptr + vaddr.rfx * 8, &rfte.val);
+ if (rc)
+ return rc;
+ if (rfte.i)
+ return PGM_REGION_FIRST_TRANS;
+ if (rfte.tt != TABLE_TYPE_REGION1)
+ return PGM_TRANSLATION_SPEC;
+ if (vaddr.rsx01 < rfte.tf || vaddr.rsx01 > rfte.tl)
+ return PGM_REGION_SECOND_TRANS;
+ if (sg->edat_level >= 1)
+ *dat_protection |= rfte.p;
+ ptr = rfte.rto << 12UL;
+shadow_r2t:
+ rc = gmap_shadow_r2t(sg, saddr, rfte.val, *fake);
+ if (rc)
+ return rc;
+ /* fallthrough */
+ }
+ case ASCE_TYPE_REGION2: {
+ union region2_table_entry rste;
+
+ if (*fake) {
+ /* offset in 8PB guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.rtx << 42UL);
+ rste.val = ptr;
+ goto shadow_r3t;
+ }
+ rc = gmap_read_table(parent, ptr + vaddr.rsx * 8, &rste.val);
+ if (rc)
+ return rc;
+ if (rste.i)
+ return PGM_REGION_SECOND_TRANS;
+ if (rste.tt != TABLE_TYPE_REGION2)
+ return PGM_TRANSLATION_SPEC;
+ if (vaddr.rtx01 < rste.tf || vaddr.rtx01 > rste.tl)
+ return PGM_REGION_THIRD_TRANS;
+ if (sg->edat_level >= 1)
+ *dat_protection |= rste.p;
+ ptr = rste.rto << 12UL;
+shadow_r3t:
+ rste.p |= *dat_protection;
+ rc = gmap_shadow_r3t(sg, saddr, rste.val, *fake);
+ if (rc)
+ return rc;
+ /* fallthrough */
+ }
+ case ASCE_TYPE_REGION3: {
+ union region3_table_entry rtte;
+
+ if (*fake) {
+ /* offset in 4TB guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.sx << 31UL);
+ rtte.val = ptr;
+ goto shadow_sgt;
+ }
+ rc = gmap_read_table(parent, ptr + vaddr.rtx * 8, &rtte.val);
+ if (rc)
+ return rc;
+ if (rtte.i)
+ return PGM_REGION_THIRD_TRANS;
+ if (rtte.tt != TABLE_TYPE_REGION3)
+ return PGM_TRANSLATION_SPEC;
+ if (rtte.cr && asce.p && sg->edat_level >= 2)
+ return PGM_TRANSLATION_SPEC;
+ if (rtte.fc && sg->edat_level >= 2) {
+ *dat_protection |= rtte.fc0.p;
+ *fake = 1;
+ ptr = rtte.fc1.rfaa << 31UL;
+ rtte.val = ptr;
+ goto shadow_sgt;
+ }
+ if (vaddr.sx01 < rtte.fc0.tf || vaddr.sx01 > rtte.fc0.tl)
+ return PGM_SEGMENT_TRANSLATION;
+ if (sg->edat_level >= 1)
+ *dat_protection |= rtte.fc0.p;
+ ptr = rtte.fc0.sto << 12UL;
+shadow_sgt:
+ rtte.fc0.p |= *dat_protection;
+ rc = gmap_shadow_sgt(sg, saddr, rtte.val, *fake);
+ if (rc)
+ return rc;
+ /* fallthrough */
+ }
+ case ASCE_TYPE_SEGMENT: {
+ union segment_table_entry ste;
+
+ if (*fake) {
+ /* offset in 2G guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.sx << 20UL);
+ ste.val = ptr;
+ goto shadow_pgt;
+ }
+ rc = gmap_read_table(parent, ptr + vaddr.sx * 8, &ste.val);
+ if (rc)
+ return rc;
+ if (ste.i)
+ return PGM_SEGMENT_TRANSLATION;
+ if (ste.tt != TABLE_TYPE_SEGMENT)
+ return PGM_TRANSLATION_SPEC;
+ if (ste.cs && asce.p)
+ return PGM_TRANSLATION_SPEC;
+ *dat_protection |= ste.fc0.p;
+ if (ste.fc && sg->edat_level >= 1) {
+ *fake = 1;
+ ptr = ste.fc1.sfaa << 20UL;
+ ste.val = ptr;
+ goto shadow_pgt;
+ }
+ ptr = ste.fc0.pto << 11UL;
+shadow_pgt:
+ ste.fc0.p |= *dat_protection;
+ rc = gmap_shadow_pgt(sg, saddr, ste.val, *fake);
+ if (rc)
+ return rc;
+ }
+ }
+ /* Return the parent address of the page table */
+ *pgt = ptr;
+ return 0;
+}
+
+/**
+ * kvm_s390_shadow_fault - handle fault on a shadow page table
+ * @vcpu: virtual cpu
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ *
+ * Returns: - 0 if the shadow fault was successfully resolved
+ * - > 0 (pgm exception code) on exceptions while faulting
+ * - -EAGAIN if the caller can retry immediately
+ * - -EFAULT when accessing invalid guest addresses
+ * - -ENOMEM if out of memory
+ */
+int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
+ unsigned long saddr)
+{
+ union vaddress vaddr;
+ union page_table_entry pte;
+ unsigned long pgt;
+ int dat_protection, fake;
+ int rc;
+
+ down_read(&sg->mm->mmap_sem);
+ /*
+ * We don't want any guest-2 tables to change - so the parent
+ * tables/pointers we read stay valid - unshadowing is however
+ * always possible - only guest_table_lock protects us.
+ */
+ ipte_lock(vcpu);
+
+ rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection, &fake);
+ if (rc)
+ rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection,
+ &fake);
+
+ vaddr.addr = saddr;
+ if (fake) {
+ /* offset in 1MB guest memory block */
+ pte.val = pgt + ((unsigned long) vaddr.px << 12UL);
+ goto shadow_page;
+ }
+ if (!rc)
+ rc = gmap_read_table(sg->parent, pgt + vaddr.px * 8, &pte.val);
+ if (!rc && pte.i)
+ rc = PGM_PAGE_TRANSLATION;
+ if (!rc && (pte.z || (pte.co && sg->edat_level < 1)))
+ rc = PGM_TRANSLATION_SPEC;
+shadow_page:
+ pte.p |= dat_protection;
+ if (!rc)
+ rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
+ ipte_unlock(vcpu);
+ up_read(&sg->mm->mmap_sem);
+ return rc;
}