target-ppc: kvm: make use of KVM_CREATE_SPAPR_TCE_64

KVM_CAP_SPAPR_TCE capability allows creating TCE tables in KVM which
allows having in-kernel acceleration for H_PUT_TCE_xxx hypercalls.
However it only supports 32bit DMA windows at zero bus offset.

There is a new KVM_CAP_SPAPR_TCE_64 capability which supports 64bit
window size, variable page size and bus offset.

This makes use of the new capability. The kernel headers are already
updated as the kernel support went in to v4.6.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index ae30bbe30f31050263367e16895f24ad93d7222c..29c80bb3c8c2236a9b62268a33c1d32088fbeb60 100644 (file)
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -79,15 +79,16 @@ static IOMMUAccessFlags spapr_tce_iommu_access_flags(uint64_t tce)
 
 static uint64_t *spapr_tce_alloc_table(uint32_t liobn,
                                        uint32_t page_shift,
+                                       uint64_t bus_offset,
                                        uint32_t nb_table,
                                        int *fd,
                                        bool need_vfio)
 {
     uint64_t *table = NULL;
-    uint64_t window_size = (uint64_t)nb_table << page_shift;
 
-    if (kvm_enabled() && !(window_size >> 32)) {
-        table = kvmppc_create_spapr_tce(liobn, window_size, fd, need_vfio);
+    if (kvm_enabled()) {
+        table = kvmppc_create_spapr_tce(liobn, page_shift, bus_offset, nb_table,
+                                        fd, need_vfio);
     }
 
     if (!table) {
@@ -342,6 +343,7 @@ void spapr_tce_table_enable(sPAPRTCETable *tcet,
     tcet->nb_table = nb_table;
     tcet->table = spapr_tce_alloc_table(tcet->liobn,
                                         tcet->page_shift,
+                                        tcet->bus_offset,
                                         tcet->nb_table,
                                         &tcet->fd,
                                         tcet->need_vfio);

diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index c3d426292c345619af1ae88f94861690e1e94aa7..79b90a6910ff63336586085c9f8e2688bcfb5c8a 100644 (file)
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -74,6 +74,7 @@ static int cap_booke_sregs;
 static int cap_ppc_smt;
 static int cap_ppc_rma;
 static int cap_spapr_tce;
+static int cap_spapr_tce_64;
 static int cap_spapr_multitce;
 static int cap_spapr_vfio;
 static int cap_hior;
@@ -126,6 +127,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     cap_ppc_smt = kvm_check_extension(s, KVM_CAP_PPC_SMT);
     cap_ppc_rma = kvm_check_extension(s, KVM_CAP_PPC_RMA);
     cap_spapr_tce = kvm_check_extension(s, KVM_CAP_SPAPR_TCE);
+    cap_spapr_tce_64 = kvm_check_extension(s, KVM_CAP_SPAPR_TCE_64);
     cap_spapr_multitce = kvm_check_extension(s, KVM_CAP_SPAPR_MULTITCE);
     cap_spapr_vfio = false;
     cap_one_reg = kvm_check_extension(s, KVM_CAP_ONE_REG);
@@ -2136,13 +2138,10 @@ bool kvmppc_spapr_use_multitce(void)
     return cap_spapr_multitce;
 }
 
-void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t window_size, int *pfd,
-                              bool need_vfio)
+void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t page_shift,
+                              uint64_t bus_offset, uint32_t nb_table,
+                              int *pfd, bool need_vfio)
 {
-    struct kvm_create_spapr_tce args = {
-        .liobn = liobn,
-        .window_size = window_size,
-    };
     long len;
     int fd;
     void *table;
@@ -2155,14 +2154,41 @@ void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t window_size, int *pfd,
         return NULL;
     }
 
-    fd = kvm_vm_ioctl(kvm_state, KVM_CREATE_SPAPR_TCE, &args);
-    if (fd < 0) {
-        fprintf(stderr, "KVM: Failed to create TCE table for liobn 0x%x\n",
-                liobn);
+    if (cap_spapr_tce_64) {
+        struct kvm_create_spapr_tce_64 args = {
+            .liobn = liobn,
+            .page_shift = page_shift,
+            .offset = bus_offset >> page_shift,
+            .size = nb_table,
+            .flags = 0
+        };
+        fd = kvm_vm_ioctl(kvm_state, KVM_CREATE_SPAPR_TCE_64, &args);
+        if (fd < 0) {
+            fprintf(stderr,
+                    "KVM: Failed to create TCE64 table for liobn 0x%x\n",
+                    liobn);
+            return NULL;
+        }
+    } else if (cap_spapr_tce) {
+        uint64_t window_size = (uint64_t) nb_table << page_shift;
+        struct kvm_create_spapr_tce args = {
+            .liobn = liobn,
+            .window_size = window_size,
+        };
+        if ((window_size != args.window_size) || bus_offset) {
+            return NULL;
+        }
+        fd = kvm_vm_ioctl(kvm_state, KVM_CREATE_SPAPR_TCE, &args);
+        if (fd < 0) {
+            fprintf(stderr, "KVM: Failed to create TCE table for liobn 0x%x\n",
+                    liobn);
+            return NULL;
+        }
+    } else {
         return NULL;
     }
 
-    len = (window_size / SPAPR_TCE_PAGE_SIZE) * sizeof(uint64_t);
+    len = nb_table * sizeof(uint64_t);
     /* FIXME: round this up to page size */
 
     table = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);

diff --git a/target/ppc/kvm_ppc.h b/target/ppc/kvm_ppc.h
index 8e9f42d0c6647d90a1f1d7ef28041df8fd26aee6..08ecf75a460c2390bfc7fbaf07171159894d032b 100644 (file)
--- a/target/ppc/kvm_ppc.h
+++ b/target/ppc/kvm_ppc.h
@@ -36,8 +36,9 @@ int kvmppc_booke_watchdog_enable(PowerPCCPU *cpu);
 #ifndef CONFIG_USER_ONLY
 off_t kvmppc_alloc_rma(void **rma);
 bool kvmppc_spapr_use_multitce(void);
-void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t window_size, int *pfd,
-                              bool need_vfio);
+void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t page_shift,
+                              uint64_t bus_offset, uint32_t nb_table,
+                              int *pfd, bool need_vfio);
 int kvmppc_remove_spapr_tce(void *table, int pfd, uint32_t window_size);
 int kvmppc_reset_htab(int shift_hint);
 uint64_t kvmppc_rma_size(uint64_t current_size, unsigned int hash_shift);
@@ -167,9 +168,10 @@ static inline bool kvmppc_spapr_use_multitce(void)
     return false;
 }
 
-static inline void *kvmppc_create_spapr_tce(uint32_t liobn,
-                                            uint32_t window_size, int *fd,
-                                            bool need_vfio)
+static inline void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t page_shift,
+                                            uint64_t bus_offset,
+                                            uint32_t nb_table,
+                                            int *pfd, bool need_vfio)
 {
     return NULL;
 }