Re: [Qemu-ppc] [PATCH v5 4/7] target/ppc: Implement H_REGISTER_PROCESS_TABLE H_CALL

[Sam Bobroff]

On Mon, Mar 20, 2017 at 10:46:46AM +1100, Sam Bobroff wrote:
> From: Suraj Jitindar Singh <address@hidden>
> 
> The H_REGISTER_PROCESS_TABLE H_CALL is used by a guest to indicate to the
> hypervisor where in memory its process table is and how translation should
> be performed using this process table.
> 
> Provide the implementation of this H_CALL for a guest.
> 
> We first check for invalid flags, then parse the flags to determine the
> operation, and then check the other parameters for valid values based on
> the operation (register new table/deregister table/maintain registration).
> The process table is then stored in the appropriate location and registered
> with the hypervisor (if running under KVM), and the LPCR_[UPRT/GTSE] bits
> are updated as required.
> 
> Signed-off-by: Suraj Jitindar Singh <address@hidden>
> Signed-off-by: Sam Bobroff <address@hidden>
> ---
> Changes in v5:
> * Corrected "compacted" case statement.
> * Re-arranged a bit and added non-KVM stub for kvmppc_configure_v3_mmu() to 
> fix
>   compile without KVM.
> * Merged the parts of "Only setup HPT if necessary" that do not rely on the 
> new
>   option vector parsing (introduced later) into this patch, this covered the
>   line that was from a stray hunk and reduced churn.
> 
>  hw/ppc/spapr.c         |  35 +++++++++------
>  hw/ppc/spapr_hcall.c   | 113 
> +++++++++++++++++++++++++++++++++++++++++++++++--
>  include/hw/ppc/spapr.h |   1 +
>  target/ppc/kvm.c       |  31 ++++++++++++++
>  target/ppc/kvm_ppc.h   |  10 +++++
>  5 files changed, 175 insertions(+), 15 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index d96e5f60fe..8f14914eea 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -40,6 +40,7 @@
>  #include "kvm_ppc.h"
>  #include "migration/migration.h"
>  #include "mmu-hash64.h"
> +#include "mmu-book3s-v3.h"
>  #include "qom/cpu.h"
>  
>  #include "hw/boards.h"
> @@ -1112,7 +1113,7 @@ static int get_htab_fd(sPAPRMachineState *spapr)
>      return spapr->htab_fd;
>  }
>  
> -static void close_htab_fd(sPAPRMachineState *spapr)
> +void close_htab_fd(sPAPRMachineState *spapr)
>  {
>      if (spapr->htab_fd >= 0) {
>          close(spapr->htab_fd);
> @@ -1239,6 +1240,19 @@ static void spapr_reallocate_hpt(sPAPRMachineState 
> *spapr, int shift,
>      }
>  }
>  
> +void spapr_setup_hpt_and_vrma(sPAPRMachineState *spapr)
> +{
> +    spapr_reallocate_hpt(spapr,
> +                     
> spapr_hpt_shift_for_ramsize(MACHINE(spapr)->maxram_size),
> +                     &error_fatal);
> +    if (spapr->vrma_adjust) {
> +        spapr->rma_size = kvmppc_rma_size(spapr_node0_size(),
> +                                          spapr->htab_shift);
> +    }
> +    /* We're setting up a hash table, so that means we're not radix */
> +    spapr->patb_entry = 0;
> +}
> +
>  static void find_unknown_sysbus_device(SysBusDevice *sbdev, void *opaque)
>  {
>      bool matched = false;
> @@ -1267,17 +1281,14 @@ static void ppc_spapr_reset(void)
>      /* Check for unknown sysbus devices */
>      foreach_dynamic_sysbus_device(find_unknown_sysbus_device, NULL);
>  
> -    spapr->patb_entry = 0;
> -
> -    /* Allocate and/or reset the hash page table */
> -    spapr_reallocate_hpt(spapr,
> -                         spapr_hpt_shift_for_ramsize(machine->maxram_size),
> -                         &error_fatal);
> -
> -    /* Update the RMA size if necessary */
> -    if (spapr->vrma_adjust) {
> -        spapr->rma_size = kvmppc_rma_size(spapr_node0_size(),
> -                                          spapr->htab_shift);
> +    if (kvm_enabled() && kvmppc_has_cap_mmu_radix()) {
> +        /* If using KVM with radix mode available, VCPUs can be started
> +         * without a HPT because KVM will start them in radix mode.
> +         * Set the GR bit in PATB so that we know there is no HPT. */
> +        spapr->patb_entry = PATBE1_GR;
> +    } else {
> +        spapr->patb_entry = 0;
> +        spapr_setup_hpt_and_vrma(spapr);
>      }
>  
>      qemu_devices_reset();
> diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> index 87b94ef9e7..374eb0cc37 100644
> --- a/hw/ppc/spapr_hcall.c
> +++ b/hw/ppc/spapr_hcall.c
> @@ -12,6 +12,8 @@
>  #include "trace.h"
>  #include "kvm_ppc.h"
>  #include "hw/ppc/spapr_ovec.h"
> +#include "qemu/error-report.h"
> +#include "mmu-book3s-v3.h"
>  
>  struct SPRSyncState {
>      int spr;
> @@ -894,14 +896,119 @@ static target_ulong h_invalidate_pid(PowerPCCPU *cpu, 
> sPAPRMachineState *spapr,
>      return H_FUNCTION;
>  }
>  
> +static void spapr_check_setup_free_hpt(sPAPRMachineState *spapr,
> +                                       uint64_t patbe_old, uint64_t 
> patbe_new)
> +{
> +    /*
> +     * We have 4 Options:
> +     * HASH->HASH || RADIX->RADIX || NOTHING->RADIX : Do Nothing
> +     * HASH->RADIX                                  : Free HPT
> +     * RADIX->HASH                                  : Allocate HPT
> +     * NOTHING->HASH                                : Allocate HPT
> +     * Note: NOTHING implies the case where we said the guest could choose
> +     *       later and so assumed radix and now it's called H_REG_PROC_TBL
> +     */
> +
> +    if ((patbe_old & PATBE1_GR) == (patbe_new & PATBE1_GR)) {
> +        /* We assume RADIX, so this catches all the "Do Nothing" cases */
> +    } else if (!(patbe_old & PATBE1_GR)) {
> +        /* HASH->RADIX : Free HPT */
> +        g_free(spapr->htab);
> +        spapr->htab = NULL;
> +        spapr->htab_shift = 0;
> +        close_htab_fd(spapr);
> +    } else if (!(patbe_new & PATBE1_GR)) {
> +        /* RADIX->HASH || NOTHING->HASH : Allocate HPT */
> +        spapr_setup_hpt_and_vrma(spapr);
> +    }
> +    return;
> +}
> +
> +#define FLAGS_MASK              0x01FULL
> +#define FLAG_MODIFY             0x10
> +#define FLAG_REGISTER           0x08
> +#define FLAG_RADIX              0x04
> +#define FLAG_HASH_PROC_TBL      0x02
> +#define FLAG_GTSE               0x01
> +
>  static target_ulong h_register_process_table(PowerPCCPU *cpu,
>                                               sPAPRMachineState *spapr,
>                                               target_ulong opcode,
>                                               target_ulong *args)
>  {
> -    qemu_log_mask(LOG_UNIMP, "Unimplemented SPAPR hcall 0x" TARGET_FMT_lx 
> "%s\n",
> -                  opcode, " (H_REGISTER_PROC_TBL)");
> -    return H_FUNCTION;
> +    CPUPPCState *env = &cpu->env;
> +    target_ulong flags = args[0];
> +    target_ulong proc_tbl = args[1];
> +    target_ulong page_size = args[2];
> +    target_ulong table_size = args[3];
> +    uint64_t cproc;
> +
> +    if (flags & ~FLAGS_MASK) { /* Check no reserved bits are set */
> +        return H_PARAMETER;
> +    }
> +    if (flags & FLAG_MODIFY) {
> +        if (flags & FLAG_REGISTER) {
> +            if (flags & FLAG_RADIX) { /* Register new RADIX process table */
> +                if (proc_tbl & 0xfff || proc_tbl >> 60) {
> +                    return H_P2;
> +                } else if (page_size) {
> +                    return H_P3;
> +                } else if (table_size > 24) {
> +                    return H_P4;
> +                }
> +                cproc = PATBE1_GR | proc_tbl | table_size;
> +            } else { /* Register new HPT process table */
> +                if (flags & FLAG_HASH_PROC_TBL) { /* Hash with Segment 
> Tables */
> +                    /* TODO - Not Supported */
> +                    /* Technically caused by flag bits => H_PARAMETER */
> +                    return H_PARAMETER;
> +                } else { /* Hash with SLB */
> +                    if (proc_tbl >> 38) {
> +                        return H_P2;
> +                    } else if (page_size & ~0x7) {
> +                        return H_P3;
> +                    } else if (table_size > 24) {
> +                        return H_P4;
> +                    }
> +                }
> +                cproc = (proc_tbl << 25) | page_size << 5 | table_size;
> +            }
> +
> +        } else { /* Deregister current process table */
> +            /* Set to benign value: (current GR) | 0. This allows
> +             * deregistration in KVM to succeed even if the radix bit in 
> flags
> +             * doesn't match the radix bit in the old PATB. */
> +            cproc = spapr->patb_entry & PATBE1_GR;
> +        }
> +    } else { /* Maintain current registration */
> +        if (!(flags & FLAG_RADIX) != !(spapr->patb_entry & PATBE1_GR)) {
> +            /* Technically caused by flag bits => H_PARAMETER */
> +            return H_PARAMETER; /* Existing Process Table Mismatch */
> +        }
> +        cproc = spapr->patb_entry;
> +    }
> +
> +    /* Check if we need to setup OR free the hpt */
> +    spapr_check_setup_free_hpt(spapr, spapr->patb_entry, cproc);
> +
> +    spapr->patb_entry = cproc; /* Save new process table */
> +    if ((flags & FLAG_RADIX) || (flags & FLAG_HASH_PROC_TBL)) {
> +        /* Use Process TBL */
> +        env->spr[SPR_LPCR] |= LPCR_UPRT;
> +    } else {
> +        env->spr[SPR_LPCR] &= ~LPCR_UPRT;
> +    }
> +    if (flags & FLAG_GTSE) { /* Partition Uses Guest Translation Shootdwn */
> +        env->spr[SPR_LPCR] |= LPCR_GTSE;
> +    } else {
> +        env->spr[SPR_LPCR] &= ~LPCR_GTSE;
> +    }
> +
> +    if (kvm_enabled()) {
> +        return kvmppc_configure_v3_mmu(cpu, flags & FLAG_RADIX,
> +                                       flags & FLAG_GTSE, cproc);
> +    }
> +    return H_SUCCESS;
>  }
>  
>  #define H_SIGNAL_SYS_RESET_ALL         -1
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 342f7a61f4..e9a8eb47d9 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -608,6 +608,7 @@ void spapr_dt_events(sPAPRMachineState *sm, void *fdt);
>  int spapr_h_cas_compose_response(sPAPRMachineState *sm,
>                                   target_ulong addr, target_ulong size,
>                                   sPAPROptionVector *ov5_updates);
> +void close_htab_fd(sPAPRMachineState *spapr);
>  sPAPRTCETable *spapr_tce_new_table(DeviceState *owner, uint32_t liobn);
>  void spapr_tce_table_enable(sPAPRTCETable *tcet,
>                              uint32_t page_shift, uint64_t bus_offset,
> diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
> index b7c08ec2ec..5a5bea0794 100644
> --- a/target/ppc/kvm.c
> +++ b/target/ppc/kvm.c
> @@ -361,6 +361,37 @@ struct ppc_radix_page_info *kvm_get_radix_page_info(void)
>      return radix_page_info;
>  }
>  
> +target_ulong kvmppc_configure_v3_mmu(PowerPCCPU *cpu,
> +                                     bool radix, bool gtse,
> +                                     uint64_t proc_tbl)
> +{
> +    CPUState *cs = CPU(cpu);
> +    int ret;
> +    uint64_t flags;

Sorry, this should be:
       uint64_t flags = 0;

> +    struct kvm_ppc_mmuv3_cfg cfg = {
> +        .process_table = proc_tbl,
> +    };
> +
> +    if (radix) {
> +        flags |= KVM_PPC_MMUV3_RADIX;
> +    }
> +    if (gtse) {
> +        flags |= KVM_PPC_MMUV3_GTSE;
> +    }
> +    cfg.flags = flags;
> +    ret = kvm_vm_ioctl(cs->kvm_state, KVM_PPC_CONFIGURE_V3_MMU, &cfg);
> +    switch (ret) {
> +    case 0:
> +        return H_SUCCESS;
> +    case -EINVAL:
> +        return H_PARAMETER;
> +    case -ENODEV:
> +        return H_NOT_AVAILABLE;
> +    default:
> +        return H_HARDWARE;
> +    }
> +}
> +
>  static bool kvm_valid_page_size(uint32_t flags, long rampgsize, uint32_t 
> shift)
>  {
>      if (!(flags & KVM_PPC_PAGE_SIZES_REAL)) {
> diff --git a/target/ppc/kvm_ppc.h b/target/ppc/kvm_ppc.h
> index 64189a48fa..4b2fd9a609 100644
> --- a/target/ppc/kvm_ppc.h
> +++ b/target/ppc/kvm_ppc.h
> @@ -33,6 +33,9 @@ int kvmppc_clear_tsr_bits(PowerPCCPU *cpu, uint32_t 
> tsr_bits);
>  int kvmppc_or_tsr_bits(PowerPCCPU *cpu, uint32_t tsr_bits);
>  int kvmppc_set_tcr(PowerPCCPU *cpu);
>  int kvmppc_booke_watchdog_enable(PowerPCCPU *cpu);
> +target_ulong kvmppc_configure_v3_mmu(PowerPCCPU *cpu,
> +                                     bool radix, bool gtse,
> +                                     uint64_t proc_tbl);
>  #ifndef CONFIG_USER_ONLY
>  off_t kvmppc_alloc_rma(void **rma);
>  bool kvmppc_spapr_use_multitce(void);
> @@ -159,6 +162,13 @@ static inline int 
> kvmppc_booke_watchdog_enable(PowerPCCPU *cpu)
>      return -1;
>  }
>  
> +static inline target_ulong kvmppc_configure_v3_mmu(PowerPCCPU *cpu,
> +                                     bool radix, bool gtse,
> +                                     uint64_t proc_tbl)
> +{
> +    return 0;
> +}
> +
>  #ifndef CONFIG_USER_ONLY
>  static inline off_t kvmppc_alloc_rma(void **rma)
>  {
> -- 
> 2.11.0
>