Re: [PATCH 12/43] target/ppc/mmu_common.c: Remove nx field from mmu_ctx_t

["Nicholas Piggin" <npiggin@gmail.com>]

On Mon May 27, 2024 at 9:12 AM AEST, BALATON Zoltan wrote:
> Pass it as a parameter instead. Also use named constants instead of
> hex values when extracting bits from SR.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

>
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
> ---
>  target/ppc/mmu_common.c | 24 ++++++++++++------------
>  1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/target/ppc/mmu_common.c b/target/ppc/mmu_common.c
> index c4902b7632..9f402a979d 100644
> --- a/target/ppc/mmu_common.c
> +++ b/target/ppc/mmu_common.c
> @@ -43,7 +43,6 @@ typedef struct {
>      int prot;          /* Protection bits          */
>      target_ulong ptem; /* Virtual segment ID | API */
>      int key;           /* Access key               */
> -    int nx;            /* Non-execute area         */
>  } mmu_ctx_t;
>  
>  void ppc_store_sdr1(CPUPPCState *env, target_ulong value)
> @@ -94,7 +93,7 @@ int ppc6xx_tlb_getnum(CPUPPCState *env, target_ulong eaddr,
>  
>  static int ppc6xx_tlb_pte_check(mmu_ctx_t *ctx, target_ulong pte0,
>                                  target_ulong pte1, int pteh,
> -                                MMUAccessType access_type)
> +                                MMUAccessType access_type, bool nx)
>  {
>      /* Check validity and table match */
>      if (!pte_is_valid(pte0) || ((pte0 >> 6) & 1) != pteh ||
> @@ -109,7 +108,7 @@ static int ppc6xx_tlb_pte_check(mmu_ctx_t *ctx, target_ulong pte0,
>      }
>      /* Keep the matching PTE information */
>      ctx->raddr = pte1;
> -    ctx->prot = ppc_hash32_prot(ctx->key, pte1 & HPTE32_R_PP, ctx->nx);
> +    ctx->prot = ppc_hash32_prot(ctx->key, pte1 & HPTE32_R_PP, nx);
>      if (check_prot_access_type(ctx->prot, access_type)) {
>          qemu_log_mask(CPU_LOG_MMU, "PTE access granted !\n");
>          return 0;
> @@ -121,8 +120,9 @@ static int ppc6xx_tlb_pte_check(mmu_ctx_t *ctx, target_ulong pte0,
>  
>  /* Software driven TLB helpers */
>  
> -static int ppc6xx_tlb_check(CPUPPCState *env, mmu_ctx_t *ctx,
> -                            target_ulong eaddr, MMUAccessType access_type)
> +static int ppc6xx_tlb_check(CPUPPCState *env,
> +                            mmu_ctx_t *ctx, target_ulong eaddr,
> +                            MMUAccessType access_type, bool nx)
>  {
>      ppc6xx_tlb_t *tlb;
>      target_ulong *pte1p;
> @@ -150,7 +150,7 @@ static int ppc6xx_tlb_check(CPUPPCState *env, mmu_ctx_t *ctx,
>                        access_type == MMU_DATA_STORE ? 'S' : 'L',
>                        access_type == MMU_INST_FETCH ? 'I' : 'D');
>          switch (ppc6xx_tlb_pte_check(ctx, tlb->pte0, tlb->pte1,
> -                                     0, access_type)) {
> +                                     0, access_type, nx)) {
>          case -2:
>              /* Access violation */
>              ret = -2;
> @@ -322,7 +322,7 @@ static int mmu6xx_get_physical_address(CPUPPCState *env, mmu_ctx_t *ctx,
>      hwaddr hash;
>      target_ulong vsid, sr, pgidx;
>      int ds, target_page_bits;
> -    bool pr;
> +    bool pr, nx;
>  
>      /* First try to find a BAT entry if there are any */
>      if (env->nb_BATs && get_bat_6xx_tlb(env, ctx, eaddr, access_type) == 0) {
> @@ -336,8 +336,8 @@ static int mmu6xx_get_physical_address(CPUPPCState *env, mmu_ctx_t *ctx,
>      ctx->key = (((sr & 0x20000000) && pr) ||
>                  ((sr & 0x40000000) && !pr)) ? 1 : 0;
>      ds = sr & 0x80000000 ? 1 : 0;
> -    ctx->nx = sr & 0x10000000 ? 1 : 0;
> -    vsid = sr & 0x00FFFFFF;
> +    nx = sr & SR32_NX;
> +    vsid = sr & SR32_VSID;
>      target_page_bits = TARGET_PAGE_BITS;
>      qemu_log_mask(CPU_LOG_MMU,
>                    "Check segment v=" TARGET_FMT_lx " %d " TARGET_FMT_lx
> @@ -352,10 +352,10 @@ static int mmu6xx_get_physical_address(CPUPPCState *env, mmu_ctx_t *ctx,
>      ctx->ptem = (vsid << 7) | (pgidx >> 10);
>  
>      qemu_log_mask(CPU_LOG_MMU, "pte segment: key=%d ds %d nx %d vsid "
> -                  TARGET_FMT_lx "\n", ctx->key, ds, ctx->nx, vsid);
> +                  TARGET_FMT_lx "\n", ctx->key, ds, nx, vsid);

This could be !!nx for consistency.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

>      if (!ds) {
>          /* Check if instruction fetch is allowed, if needed */
> -        if (type == ACCESS_CODE && ctx->nx) {
> +        if (type == ACCESS_CODE && nx) {
>              qemu_log_mask(CPU_LOG_MMU, "No access allowed\n");
>              return -3;
>          }
> @@ -368,7 +368,7 @@ static int mmu6xx_get_physical_address(CPUPPCState *env, mmu_ctx_t *ctx,
>          /* Initialize real address with an invalid value */
>          ctx->raddr = (hwaddr)-1ULL;
>          /* Software TLB search */
> -        return ppc6xx_tlb_check(env, ctx, eaddr, access_type);
> +        return ppc6xx_tlb_check(env, ctx, eaddr, access_type, nx);
>      }
>  
>      /* Direct-store segment : absolutely *BUGGY* for now */