mmu-hash*: Reduce use of access_type

In ppc env->access_type is updated by e.g. integer load/stores with
ACCESS_INT floating point load/stores with ACCESS_FLOAT and so forth.  In
hash mmu fault paths it can also b set to ACCESS_CODE for instruction
fetch accesses.

But the only place which uses anything more of the access_type than
whether it is instruction fetch or data access is the direct store segment
handling.  Instruction versus data access can be more simply determined
from the rw value passed down from the top.

This changes the code to use rw in preference to checking access_type.
For the 32-bit case there is a small amount of code (for direct store
segments) that still needs the full access type.  Instead of passing it
all the way down the stack, we retrieve it from the env structure, which
is where it came anyway, before this patch.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 44 insertions, 54 deletions

diff --git a/target-ppc/mmu-hash32.c b/target-ppc/mmu-hash32.c
index a7c2e356e8..ad5ef44c28 100644
--- a/target-ppc/mmu-hash32.c
+++ b/target-ppc/mmu-hash32.c
@@ -91,17 +91,17 @@ static int ppc_hash32_pp_check(int key, int pp, int nx)
     return access;
 }
 
-static int ppc_hash32_check_prot(int prot, int rw, int access_type)
+static int ppc_hash32_check_prot(int prot, int rwx)
 {
     int ret;
 
-    if (access_type == ACCESS_CODE) {
+    if (rwx == 2) {
         if (prot & PAGE_EXEC) {
             ret = 0;
         } else {
             ret = -2;
         }
-    } else if (rw) {
+    } else if (rwx) {
         if (prot & PAGE_WRITE) {
             ret = 0;
         } else {
@@ -172,7 +172,7 @@ static void hash32_bat_601_size_prot(CPUPPCState *env, target_ulong *blp,
 }
 
 static int ppc_hash32_get_bat(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
-                              target_ulong virtual, int rw, int type)
+                              target_ulong virtual, int rwx)
 {
     target_ulong *BATlt, *BATut, *BATu, *BATl;
     target_ulong BEPIl, BEPIu, bl;
@@ -180,16 +180,13 @@ static int ppc_hash32_get_bat(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
     int ret = -1;
 
     LOG_BATS("%s: %cBAT v " TARGET_FMT_lx "\n", __func__,
-             type == ACCESS_CODE ? 'I' : 'D', virtual);
-    switch (type) {
-    case ACCESS_CODE:
+             rwx == 2 ? 'I' : 'D', virtual);
+    if (rwx == 2) {
         BATlt = env->IBAT[1];
         BATut = env->IBAT[0];
-        break;
-    default:
+    } else {
         BATlt = env->DBAT[1];
         BATut = env->DBAT[0];
-        break;
     }
     for (i = 0; i < env->nb_BATs; i++) {
         BATu = &BATut[i];
@@ -214,7 +211,7 @@ static int ppc_hash32_get_bat(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
                     (virtual & 0x0001F000);
                 /* Compute access rights */
                 ctx->prot = prot;
-                ret = ppc_hash32_check_prot(ctx->prot, rw, type);
+                ret = ppc_hash32_check_prot(ctx->prot, rwx);
                 if (ret == 0) {
                     LOG_BATS("BAT %d match: r " TARGET_FMT_plx " prot=%c%c\n",
                              i, ctx->raddr, ctx->prot & PAGE_READ ? 'R' : '-',
@@ -248,7 +245,7 @@ static int ppc_hash32_get_bat(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
 }
 
 static int pte_check_hash32(struct mmu_ctx_hash32 *ctx, target_ulong pte0,
-                            target_ulong pte1, int h, int rw, int type)
+                            target_ulong pte1, int h, int rwx)
 {
     target_ulong mmask;
     int access, ret, pp;
@@ -272,7 +269,7 @@ static int pte_check_hash32(struct mmu_ctx_hash32 *ctx, target_ulong pte0,
             /* Keep the matching PTE informations */
             ctx->raddr = pte1;
             ctx->prot = access;
-            ret = ppc_hash32_check_prot(ctx->prot, rw, type);
+            ret = ppc_hash32_check_prot(ctx->prot, rwx);
             if (ret == 0) {
                 /* Access granted */
                 LOG_MMU("PTE access granted !\n");
@@ -287,7 +284,7 @@ static int pte_check_hash32(struct mmu_ctx_hash32 *ctx, target_ulong pte0,
 }
 
 static int ppc_hash32_pte_update_flags(struct mmu_ctx_hash32 *ctx, target_ulong *pte1p,
-                                       int ret, int rw)
+                                       int ret, int rwx)
 {
     int store = 0;
 
@@ -298,7 +295,7 @@ static int ppc_hash32_pte_update_flags(struct mmu_ctx_hash32 *ctx, target_ulong
         store = 1;
     }
     if (!(*pte1p & HPTE32_R_C)) {
-        if (rw == 1 && ret == 0) {
+        if (rwx == 1 && ret == 0) {
             /* Update changed flag */
             *pte1p |= HPTE32_R_C;
             store = 1;
@@ -318,7 +315,7 @@ hwaddr get_pteg_offset32(CPUPPCState *env, hwaddr hash)
 
 /* PTE table lookup */
 static int find_pte32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx, int h,
-                      int rw, int type, int target_page_bits)
+                      int rwx, int target_page_bits)
 {
     hwaddr pteg_off;
     target_ulong pte0, pte1;
@@ -330,7 +327,7 @@ static int find_pte32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx, int h,
     for (i = 0; i < HPTES_PER_GROUP; i++) {
         pte0 = ppc_hash32_load_hpte0(env, pteg_off + i*HASH_PTE_SIZE_32);
         pte1 = ppc_hash32_load_hpte1(env, pteg_off + i*HASH_PTE_SIZE_32);
-        r = pte_check_hash32(ctx, pte0, pte1, h, rw, type);
+        r = pte_check_hash32(ctx, pte0, pte1, h, rwx);
         LOG_MMU("Load pte from %08" HWADDR_PRIx " => " TARGET_FMT_lx " "
                 TARGET_FMT_lx " %d %d %d " TARGET_FMT_lx "\n",
                 pteg_off + (i * 8), pte0, pte1, (int)(pte0 >> 31), h,
@@ -365,7 +362,7 @@ static int find_pte32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx, int h,
                 ctx->raddr, ctx->prot, ret);
         /* Update page flags */
         pte1 = ctx->raddr;
-        if (ppc_hash32_pte_update_flags(ctx, &pte1, ret, rw) == 1) {
+        if (ppc_hash32_pte_update_flags(ctx, &pte1, ret, rwx) == 1) {
             ppc_hash32_store_hpte1(env, pteg_off + good * HASH_PTE_SIZE_32,
                                    pte1);
         }
@@ -381,7 +378,7 @@ static int find_pte32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx, int h,
 }
 
 static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
-                         target_ulong eaddr, int rw, int type)
+                         target_ulong eaddr, int rwx)
 {
     hwaddr hash;
     target_ulong vsid;
@@ -401,9 +398,9 @@ static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
     target_page_bits = TARGET_PAGE_BITS;
     LOG_MMU("Check segment v=" TARGET_FMT_lx " %d " TARGET_FMT_lx " nip="
             TARGET_FMT_lx " lr=" TARGET_FMT_lx
-            " ir=%d dr=%d pr=%d %d t=%d\n",
+            " ir=%d dr=%d pr=%d %d\n",
             eaddr, (int)(eaddr >> 28), sr, env->nip, env->lr, (int)msr_ir,
-            (int)msr_dr, pr != 0 ? 1 : 0, rw, type);
+            (int)msr_dr, pr != 0 ? 1 : 0, rwx);
     pgidx = (eaddr & ~SEGMENT_MASK_256M) >> target_page_bits;
     hash = vsid ^ pgidx;
     ctx->ptem = (vsid << 7) | (pgidx >> 10);
@@ -413,7 +410,7 @@ static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
     ret = -1;
     if (!ds) {
         /* Check if instruction fetch is allowed, if needed */
-        if (type != ACCESS_CODE || ctx->nx == 0) {
+        if (rwx != 2 || ctx->nx == 0) {
             /* Page address translation */
             LOG_MMU("htab_base " TARGET_FMT_plx " htab_mask " TARGET_FMT_plx
                     " hash " TARGET_FMT_plx "\n",
@@ -429,15 +426,14 @@ static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
                     env->htab_base, env->htab_mask, vsid, ctx->ptem,
                     ctx->hash[0]);
             /* Primary table lookup */
-            ret = find_pte32(env, ctx, 0, rw, type, target_page_bits);
+            ret = find_pte32(env, ctx, 0, rwx, target_page_bits);
             if (ret < 0) {
                 /* Secondary table lookup */
                 LOG_MMU("1 htab=" TARGET_FMT_plx "/" TARGET_FMT_plx
                         " vsid=" TARGET_FMT_lx " api=" TARGET_FMT_lx
                         " hash=" TARGET_FMT_plx "\n", env->htab_base,
                         env->htab_mask, vsid, ctx->ptem, ctx->hash[1]);
-                ret2 = find_pte32(env, ctx, 1, rw, type,
-                                  target_page_bits);
+                ret2 = find_pte32(env, ctx, 1, rwx, target_page_bits);
                 if (ret2 != -1) {
                     ret = ret2;
                 }
@@ -486,13 +482,15 @@ static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
             return 0;
         }
 
-        switch (type) {
+        if (rwx == 2) {
+            /* No code fetch is allowed in direct-store areas */
+            return -4;
+        }
+
+        switch (env->access_type) {
         case ACCESS_INT:
             /* Integer load/store : only access allowed */
             break;
-        case ACCESS_CODE:
-            /* No code fetch is allowed in direct-store areas */
-            return -4;
         case ACCESS_FLOAT:
             /* Floating point load/store */
             return -4;
@@ -514,7 +512,7 @@ static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
                         "address translation\n");
             return -4;
         }
-        if ((rw == 1 || ctx->key != 1) && (rw == 0 || ctx->key != 0)) {
+        if ((rwx == 1 || ctx->key != 1) && (rwx == 0 || ctx->key != 0)) {
             ctx->raddr = eaddr;
             ret = 2;
         } else {
@@ -526,11 +524,10 @@ static int get_segment32(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
 }
 
 static int ppc_hash32_get_physical_address(CPUPPCState *env, struct mmu_ctx_hash32 *ctx,
-                                           target_ulong eaddr, int rw,
-                                           int access_type)
+                                           target_ulong eaddr, int rwx)
 {
-    bool real_mode = (access_type == ACCESS_CODE && msr_ir == 0)
-        || (access_type != ACCESS_CODE && msr_dr == 0);
+    bool real_mode = (rwx == 2 && msr_ir == 0)
+        || (rwx != 2 && msr_dr == 0);
 
     if (real_mode) {
         ctx->raddr = eaddr;
@@ -541,11 +538,11 @@ static int ppc_hash32_get_physical_address(CPUPPCState *env, struct mmu_ctx_hash
 
         /* Try to find a BAT */
         if (env->nb_BATs != 0) {
-            ret = ppc_hash32_get_bat(env, ctx, eaddr, rw, access_type);
+            ret = ppc_hash32_get_bat(env, ctx, eaddr, rwx);
         }
         if (ret < 0) {
             /* We didn't match any BAT entry or don't have BATs */
-            ret = get_segment32(env, ctx, eaddr, rw, access_type);
+            ret = get_segment32(env, ctx, eaddr, rwx);
         }
         return ret;
     }
@@ -555,7 +552,9 @@ hwaddr ppc_hash32_get_phys_page_debug(CPUPPCState *env, target_ulong addr)
 {
     struct mmu_ctx_hash32 ctx;
 
-    if (unlikely(ppc_hash32_get_physical_address(env, &ctx, addr, 0, ACCESS_INT)
+    /* FIXME: Will not behave sanely for direct store segments, but
+     * they're almost never used */
+    if (unlikely(ppc_hash32_get_physical_address(env, &ctx, addr, 0)
                  != 0)) {
         return -1;
     }
@@ -563,22 +562,13 @@ hwaddr ppc_hash32_get_phys_page_debug(CPUPPCState *env, target_ulong addr)
     return ctx.raddr & TARGET_PAGE_MASK;
 }
 
-int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
+int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rwx,
                                 int mmu_idx)
 {
     struct mmu_ctx_hash32 ctx;
-    int access_type;
     int ret = 0;
 
-    if (rw == 2) {
-        /* code access */
-        rw = 0;
-        access_type = ACCESS_CODE;
-    } else {
-        /* data access */
-        access_type = env->access_type;
-    }
-    ret = ppc_hash32_get_physical_address(env, &ctx, address, rw, access_type);
+    ret = ppc_hash32_get_physical_address(env, &ctx, address, rwx);
     if (ret == 0) {
         tlb_set_page(env, address & TARGET_PAGE_MASK,
                      ctx.raddr & TARGET_PAGE_MASK, ctx.prot,
@@ -586,7 +576,7 @@ int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
         ret = 0;
     } else if (ret < 0) {
         LOG_MMU_STATE(env);
-        if (access_type == ACCESS_CODE) {
+        if (rwx == 2) {
             switch (ret) {
             case -1:
                 /* No matches in page tables or TLB */
@@ -617,7 +607,7 @@ int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
                 env->exception_index = POWERPC_EXCP_DSI;
                 env->error_code = 0;
                 env->spr[SPR_DAR] = address;
-                if (rw == 1) {
+                if (rwx == 1) {
                     env->spr[SPR_DSISR] = 0x42000000;
                 } else {
                     env->spr[SPR_DSISR] = 0x40000000;
@@ -628,7 +618,7 @@ int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
                 env->exception_index = POWERPC_EXCP_DSI;
                 env->error_code = 0;
                 env->spr[SPR_DAR] = address;
-                if (rw == 1) {
+                if (rwx == 1) {
                     env->spr[SPR_DSISR] = 0x0A000000;
                 } else {
                     env->spr[SPR_DSISR] = 0x08000000;
@@ -636,7 +626,7 @@ int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
                 break;
             case -4:
                 /* Direct store exception */
-                switch (access_type) {
+                switch (env->access_type) {
                 case ACCESS_FLOAT:
                     /* Floating point load/store */
                     env->exception_index = POWERPC_EXCP_ALIGN;
@@ -648,7 +638,7 @@ int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
                     env->exception_index = POWERPC_EXCP_DSI;
                     env->error_code = 0;
                     env->spr[SPR_DAR] = address;
-                    if (rw == 1) {
+                    if (rwx == 1) {
                         env->spr[SPR_DSISR] = 0x06000000;
                     } else {
                         env->spr[SPR_DSISR] = 0x04000000;
@@ -659,7 +649,7 @@ int ppc_hash32_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
                     env->exception_index = POWERPC_EXCP_DSI;
                     env->error_code = 0;
                     env->spr[SPR_DAR] = address;
-                    if (rw == 1) {
+                    if (rwx == 1) {
                         env->spr[SPR_DSISR] = 0x06100000;
                     } else {
                         env->spr[SPR_DSISR] = 0x04100000;