[RFC,1/6] pseries: Stubs for HPT resizing

Commit Message

David Gibson March 21, 2016, 4:42 a.m. UTC

This introduces stub implementations of the H_RESIZE_HPT_PREPARE and
H_RESIZE_HPT_COMMIT hypercalls which we hope to add in a PAPR
extension to allow run time resizing of a guest's hash page table.  It
also adds a new machine property for controlling whether this new
facility is available.

Finally, it adds a new string to the hypertas property in the device
tree, advertising to the guest the availability of the HPT resizing
hypercalls.  This is a tentative suggested value, and would need to be
standardized by PAPR before being merged.

Signed-off-by: David Gibson <[e-mail]>
---
 hw/ppc/spapr.c         | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++
 hw/ppc/spapr_hcall.c   | 37 ++++++++++++++++++++++++++++
 include/hw/ppc/spapr.h | 13 +++++++++-
 target-ppc/kvm.c       | 12 ++++++++++
 target-ppc/kvm_ppc.h   |  6 +++++
 trace-events           |  2 ++
 6 files changed, 134 insertions(+), 1 deletion(-)

Patch

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index d43d6d9..a027a80 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -318,6 +318,7 @@  static void *spapr_create_fdt_skel(hwaddr initrd_base,
                                    const char *kernel_cmdline,
                                    uint32_t epow_irq)
 {
+    sPAPRMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
     void *fdt;
     uint32_t start_prop = cpu_to_be32(initrd_base);
     uint32_t end_prop = cpu_to_be32(initrd_base + initrd_size);
@@ -337,6 +338,9 @@  static void *spapr_create_fdt_skel(hwaddr initrd_base,
     add_str(hypertas, "hcall-splpar");
     add_str(hypertas, "hcall-bulk");
     add_str(hypertas, "hcall-set-mode");
+    if (spapr->resize_hpt != SPAPR_RESIZE_HPT_DISABLED) {
+        add_str(hypertas, "hcall-hpt-resize");
+    }
     add_str(qemu_hypertas, "hcall-memop1");
 
     fdt = g_malloc0(FDT_MAX_SIZE);
@@ -1733,6 +1737,7 @@  static void ppc_spapr_init(MachineState *machine)
     long load_limit, fw_size;
     bool kernel_le = false;
     char *filename;
+    Error *resize_hpt_err = NULL;
 
     msi_nonbroken = true;
 
@@ -1740,6 +1745,25 @@  static void ppc_spapr_init(MachineState *machine)
 
     cpu_ppc_hypercall = emulate_spapr_hypercall;
 
+    /* Check HPT resizing availability */
+    kvmppc_check_papr_resize_hpt(&resize_hpt_err);
+    if (spapr->resize_hpt == SPAPR_RESIZE_HPT_DEFAULT) {
+        if (resize_hpt_err) {
+            spapr->resize_hpt = SPAPR_RESIZE_HPT_DISABLED;
+            error_free(resize_hpt_err);
+            resize_hpt_err = NULL;
+        } else {
+            spapr->resize_hpt = smc->resize_hpt_default;
+        }
+    }
+
+    assert(spapr->resize_hpt != SPAPR_RESIZE_HPT_DEFAULT);
+
+    if ((spapr->resize_hpt != SPAPR_RESIZE_HPT_DISABLED) && resize_hpt_err) {
+        error_report_err(resize_hpt_err);
+        exit(1);
+    }
+
     /* Allocate RMA if necessary */
     rma_alloc_size = kvmppc_alloc_rma(&rma);
 
@@ -2093,6 +2117,40 @@  static void spapr_set_kvm_type(Object *obj, const char *value, Error **errp)
     spapr->kvm_type = g_strdup(value);
 }
 
+static char *spapr_get_resize_hpt(Object *obj, Error **errp)
+{
+    sPAPRMachineState *spapr = SPAPR_MACHINE(obj);
+
+    switch (spapr->resize_hpt) {
+    case SPAPR_RESIZE_HPT_DEFAULT:
+        return g_strdup("default");
+    case SPAPR_RESIZE_HPT_DISABLED:
+        return g_strdup("disabled");
+    case SPAPR_RESIZE_HPT_ENABLED:
+        return g_strdup("enabled");
+    case SPAPR_RESIZE_HPT_REQUIRED:
+        return g_strdup("required");
+    }
+    assert(0);
+}
+
+static void spapr_set_resize_hpt(Object *obj, const char *value, Error **errp)
+{
+    sPAPRMachineState *spapr = SPAPR_MACHINE(obj);
+
+    if (strcmp(value, "default") == 0) {
+        spapr->resize_hpt = SPAPR_RESIZE_HPT_DEFAULT;
+    } else if (strcmp(value, "disabled") == 0) {
+        spapr->resize_hpt = SPAPR_RESIZE_HPT_DISABLED;
+    } else if (strcmp(value, "enabled") == 0) {
+        spapr->resize_hpt = SPAPR_RESIZE_HPT_ENABLED;
+    } else if (strcmp(value, "required") == 0) {
+        spapr->resize_hpt = SPAPR_RESIZE_HPT_REQUIRED;
+    } else {
+        error_setg(errp, "Bad value for \"resize-hpt\" property");
+    }
+}
+
 static void spapr_machine_initfn(Object *obj)
 {
     sPAPRMachineState *spapr = SPAPR_MACHINE(obj);
@@ -2103,6 +2161,12 @@  static void spapr_machine_initfn(Object *obj)
     object_property_set_description(obj, "kvm-type",
                                     "Specifies the KVM virtualization mode (HV, PR)",
                                     NULL);
+
+    object_property_add_str(obj, "resize-hpt",
+                            spapr_get_resize_hpt, spapr_set_resize_hpt, NULL);
+    object_property_set_description(obj, "resize-hpt",
+                                    "Resizing of the Hash Page Table (enabled, disabled, required)",
+                                    NULL);
 }
 
 static void spapr_machine_finalizefn(Object *obj)
@@ -2296,6 +2360,7 @@  static void spapr_machine_class_init(ObjectClass *oc, void *data)
     mc->cpu_index_to_socket_id = spapr_cpu_index_to_socket_id;
 
     smc->dr_lmb_enabled = true;
+    smc->resize_hpt_default = SPAPR_RESIZE_HPT_DISABLED;
     fwc->get_dev_path = spapr_get_fw_dev_path;
     nc->nmi_monitor_handler = spapr_nmi;
 }
diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
index b2b1b93..0f0675e 100644
--- a/hw/ppc/spapr_hcall.c
+++ b/hw/ppc/spapr_hcall.c
@@ -338,6 +338,38 @@  static target_ulong h_read(PowerPCCPU *cpu, sPAPRMachineState *spapr,
     return H_SUCCESS;
 }
 
+static target_ulong h_resize_hpt_prepare(PowerPCCPU *cpu,
+                                         sPAPRMachineState *spapr,
+                                         target_ulong opcode,
+                                         target_ulong *args)
+{
+    target_ulong flags = args[0];
+    target_ulong shift = args[1];
+
+    if (spapr->resize_hpt == SPAPR_RESIZE_HPT_DISABLED) {
+        return H_AUTHORITY;
+    }
+
+    trace_spapr_h_resize_hpt_prepare(flags, shift);
+    return H_HARDWARE;
+}
+
+static target_ulong h_resize_hpt_commit(PowerPCCPU *cpu,
+                                        sPAPRMachineState *spapr,
+                                        target_ulong opcode,
+                                        target_ulong *args)
+{
+    target_ulong flags = args[0];
+    target_ulong shift = args[1];
+
+    if (spapr->resize_hpt == SPAPR_RESIZE_HPT_DISABLED) {
+        return H_AUTHORITY;
+    }
+
+    trace_spapr_h_resize_hpt_commit(flags, shift);
+    return H_HARDWARE;
+}
+
 static target_ulong h_set_sprg0(PowerPCCPU *cpu, sPAPRMachineState *spapr,
                                 target_ulong opcode, target_ulong *args)
 {
@@ -1096,6 +1128,11 @@  static void hypercall_register_types(void)
     /* hcall-bulk */
     spapr_register_hypercall(H_BULK_REMOVE, h_bulk_remove);
 
+    /* hcall-hpt-resize */
+    spapr_register_hypercall(KVMPPC_H_RESIZE_HPT_PREPARE,
+                             h_resize_hpt_prepare);
+    spapr_register_hypercall(KVMPPC_H_RESIZE_HPT_COMMIT, h_resize_hpt_commit);
+
     /* hcall-splpar */
     spapr_register_hypercall(H_REGISTER_VPA, h_register_vpa);
     spapr_register_hypercall(H_CEDE, h_cede);
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 098d85d..6de5135 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -27,6 +27,13 @@  typedef struct sPAPRMachineState sPAPRMachineState;
 #define SPAPR_MACHINE_CLASS(klass) \
     OBJECT_CLASS_CHECK(sPAPRMachineClass, klass, TYPE_SPAPR_MACHINE)
 
+typedef enum {
+    SPAPR_RESIZE_HPT_DEFAULT = 0,
+    SPAPR_RESIZE_HPT_DISABLED,
+    SPAPR_RESIZE_HPT_ENABLED,
+    SPAPR_RESIZE_HPT_REQUIRED,
+} sPAPRResizeHPT;
+
 /**
  * sPAPRMachineClass:
  */
@@ -37,6 +44,7 @@  struct sPAPRMachineClass {
     /*< public >*/
     bool dr_lmb_enabled;       /* enable dynamic-reconfig/hotplug of LMBs */
     bool use_ohci_by_default;  /* use USB-OHCI instead of XHCI */
+    sPAPRResizeHPT resize_hpt_default;
 };
 
 /**
@@ -52,6 +60,7 @@  struct sPAPRMachineState {
     XICSState *icp;
     DeviceState *rtc;
 
+    sPAPRResizeHPT resize_hpt;
     void *htab;
     uint32_t htab_shift;
     hwaddr rma_size;
@@ -351,7 +360,9 @@  struct sPAPRMachineState {
 #define KVMPPC_H_LOGICAL_MEMOP  (KVMPPC_HCALL_BASE + 0x1)
 /* Client Architecture support */
 #define KVMPPC_H_CAS            (KVMPPC_HCALL_BASE + 0x2)
-#define KVMPPC_HCALL_MAX        KVMPPC_H_CAS
+#define KVMPPC_H_RESIZE_HPT_PREPARE (KVMPPC_HCALL_BASE + 0x3)
+#define KVMPPC_H_RESIZE_HPT_COMMIT  (KVMPPC_HCALL_BASE + 0x4)
+#define KVMPPC_HCALL_MAX        KVMPPC_H_RESIZE_HPT_COMMIT
 
 typedef struct sPAPRDeviceTreeUpdateHeader {
     uint32_t version_id;
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index e5183db..989e1d1 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -2572,3 +2572,15 @@  int kvmppc_enable_hwrng(void)
 
     return kvmppc_enable_hcall(kvm_state, H_RANDOM);
 }
+
+void kvmppc_check_papr_resize_hpt(Error **errp)
+{
+    if (!kvm_enabled()) {
+        return;
+    }
+
+    /* KVM will need to advertise capability for HPT resizing once
+     * implemented, for now we assume that it's not possible with
+     * KVM */
+    error_setg(errp, "Hash page table resizing not available with KVM");
+}
diff --git a/target-ppc/kvm_ppc.h b/target-ppc/kvm_ppc.h
index fc79312..5446d6f 100644
--- a/target-ppc/kvm_ppc.h
+++ b/target-ppc/kvm_ppc.h
@@ -56,6 +56,7 @@  void kvmppc_hash64_write_pte(CPUPPCState *env, target_ulong pte_index,
 bool kvmppc_has_cap_fixup_hcalls(void);
 int kvmppc_enable_hwrng(void);
 int kvmppc_put_books_sregs(PowerPCCPU *cpu);
+void kvmppc_check_papr_resize_hpt(Error **errp);
 
 #else
 
@@ -252,6 +253,11 @@  static inline int kvmppc_put_books_sregs(PowerPCCPU *cpu)
 {
     abort();
 }
+
+static inline void kvmppc_check_papr_resize_hpt(Error **errp)
+{
+    return;
+}
 #endif
 
 #ifndef CONFIG_KVM
diff --git a/trace-events b/trace-events
index d494de1..dfc263f 100644
--- a/trace-events
+++ b/trace-events
@@ -1419,6 +1419,8 @@  spapr_cas_continue(unsigned long n) "Copy changes to the guest: %ld bytes"
 # hw/ppc/spapr_hcall.c
 spapr_cas_pvr_try(uint32_t pvr) "%x"
 spapr_cas_pvr(uint32_t cur_pvr, bool cpu_match, uint32_t new_pvr, uint64_t pcr) "current=%x, cpu_match=%u, new=%x, compat flags=%"PRIx64
+spapr_h_resize_hpt_prepare(uint64_t flags, uint64_t shift) "flags=0x%"PRIx64", shift=%"PRIu64
+spapr_h_resize_hpt_commit(uint64_t flags, uint64_t shift) "flags=0x%"PRIx64", shift=%"PRIu64
 
 # hw/ppc/spapr_iommu.c
 spapr_iommu_put(uint64_t liobn, uint64_t ioba, uint64_t tce, uint64_t ret) "liobn=%"PRIx64" ioba=0x%"PRIx64" tce=0x%"PRIx64" ret=%"PRId64