Move target-* CPU file into a target/ folder

We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.

Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [cris&microblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>

target/s390x/mmu_helper.c

@@ -0,0 +1,499 @@
+/*
+ * S390x MMU related functions
+ *
+ * Copyright (c) 2011 Alexander Graf
+ * Copyright (c) 2015 Thomas Huth, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/error-report.h"
+#include "exec/address-spaces.h"
+#include "cpu.h"
+#include "sysemu/kvm.h"
+#include "trace.h"
+#include "hw/s390x/storage-keys.h"
+
+/* #define DEBUG_S390 */
+/* #define DEBUG_S390_PTE */
+/* #define DEBUG_S390_STDOUT */
+
+#ifdef DEBUG_S390
+#ifdef DEBUG_S390_STDOUT
+#define DPRINTF(fmt, ...) \
+    do { fprintf(stderr, fmt, ## __VA_ARGS__); \
+         if (qemu_log_separate()) qemu_log(fmt, ##__VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+    do { qemu_log(fmt, ## __VA_ARGS__); } while (0)
+#endif
+#else
+#define DPRINTF(fmt, ...) \
+    do { } while (0)
+#endif
+
+#ifdef DEBUG_S390_PTE
+#define PTE_DPRINTF DPRINTF
+#else
+#define PTE_DPRINTF(fmt, ...) \
+    do { } while (0)
+#endif
+
+/* Fetch/store bits in the translation exception code: */
+#define FS_READ  0x800
+#define FS_WRITE 0x400
+
+static void trigger_access_exception(CPUS390XState *env, uint32_t type,
+                                     uint32_t ilen, uint64_t tec)
+{
+    S390CPU *cpu = s390_env_get_cpu(env);
+
+    if (kvm_enabled()) {
+        kvm_s390_access_exception(cpu, type, tec);
+    } else {
+        CPUState *cs = CPU(cpu);
+        stq_phys(cs->as, env->psa + offsetof(LowCore, trans_exc_code), tec);
+        trigger_pgm_exception(env, type, ilen);
+    }
+}
+
+static void trigger_prot_fault(CPUS390XState *env, target_ulong vaddr,
+                               uint64_t asc, int rw, bool exc)
+{
+    uint64_t tec;
+
+    tec = vaddr | (rw == MMU_DATA_STORE ? FS_WRITE : FS_READ) | 4 | asc >> 46;
+
+    DPRINTF("%s: trans_exc_code=%016" PRIx64 "\n", __func__, tec);
+
+    if (!exc) {
+        return;
+    }
+
+    trigger_access_exception(env, PGM_PROTECTION, ILEN_LATER_INC, tec);
+}
+
+static void trigger_page_fault(CPUS390XState *env, target_ulong vaddr,
+                               uint32_t type, uint64_t asc, int rw, bool exc)
+{
+    int ilen = ILEN_LATER;
+    uint64_t tec;
+
+    tec = vaddr | (rw == MMU_DATA_STORE ? FS_WRITE : FS_READ) | asc >> 46;
+
+    DPRINTF("%s: trans_exc_code=%016" PRIx64 "\n", __func__, tec);
+
+    if (!exc) {
+        return;
+    }
+
+    /* Code accesses have an undefined ilc.  */
+    if (rw == MMU_INST_FETCH) {
+        ilen = 2;
+    }
+
+    trigger_access_exception(env, type, ilen, tec);
+}
+
+/**
+ * Translate real address to absolute (= physical)
+ * address by taking care of the prefix mapping.
+ */
+static target_ulong mmu_real2abs(CPUS390XState *env, target_ulong raddr)
+{
+    if (raddr < 0x2000) {
+        return raddr + env->psa;    /* Map the lowcore. */
+    } else if (raddr >= env->psa && raddr < env->psa + 0x2000) {
+        return raddr - env->psa;    /* Map the 0 page. */
+    }
+    return raddr;
+}
+
+/* Decode page table entry (normal 4KB page) */
+static int mmu_translate_pte(CPUS390XState *env, target_ulong vaddr,
+                             uint64_t asc, uint64_t pt_entry,
+                             target_ulong *raddr, int *flags, int rw, bool exc)
+{
+    if (pt_entry & _PAGE_INVALID) {
+        DPRINTF("%s: PTE=0x%" PRIx64 " invalid\n", __func__, pt_entry);
+        trigger_page_fault(env, vaddr, PGM_PAGE_TRANS, asc, rw, exc);
+        return -1;
+    }
+    if (pt_entry & _PAGE_RES0) {
+        trigger_page_fault(env, vaddr, PGM_TRANS_SPEC, asc, rw, exc);
+        return -1;
+    }
+    if (pt_entry & _PAGE_RO) {
+        *flags &= ~PAGE_WRITE;
+    }
+
+    *raddr = pt_entry & _ASCE_ORIGIN;
+
+    PTE_DPRINTF("%s: PTE=0x%" PRIx64 "\n", __func__, pt_entry);
+
+    return 0;
+}
+
+#define VADDR_PX    0xff000         /* Page index bits */
+
+/* Decode segment table entry */
+static int mmu_translate_segment(CPUS390XState *env, target_ulong vaddr,
+                                 uint64_t asc, uint64_t st_entry,
+                                 target_ulong *raddr, int *flags, int rw,
+                                 bool exc)
+{
+    CPUState *cs = CPU(s390_env_get_cpu(env));
+    uint64_t origin, offs, pt_entry;
+
+    if (st_entry & _SEGMENT_ENTRY_RO) {
+        *flags &= ~PAGE_WRITE;
+    }
+
+    if ((st_entry & _SEGMENT_ENTRY_FC) && (env->cregs[0] & CR0_EDAT)) {
+        /* Decode EDAT1 segment frame absolute address (1MB page) */
+        *raddr = (st_entry & 0xfffffffffff00000ULL) | (vaddr & 0xfffff);
+        PTE_DPRINTF("%s: SEG=0x%" PRIx64 "\n", __func__, st_entry);
+        return 0;
+    }
+
+    /* Look up 4KB page entry */
+    origin = st_entry & _SEGMENT_ENTRY_ORIGIN;
+    offs  = (vaddr & VADDR_PX) >> 9;
+    pt_entry = ldq_phys(cs->as, origin + offs);
+    PTE_DPRINTF("%s: 0x%" PRIx64 " + 0x%" PRIx64 " => 0x%016" PRIx64 "\n",
+                __func__, origin, offs, pt_entry);
+    return mmu_translate_pte(env, vaddr, asc, pt_entry, raddr, flags, rw, exc);
+}
+
+/* Decode region table entries */
+static int mmu_translate_region(CPUS390XState *env, target_ulong vaddr,
+                                uint64_t asc, uint64_t entry, int level,
+                                target_ulong *raddr, int *flags, int rw,
+                                bool exc)
+{
+    CPUState *cs = CPU(s390_env_get_cpu(env));
+    uint64_t origin, offs, new_entry;
+    const int pchks[4] = {
+        PGM_SEGMENT_TRANS, PGM_REG_THIRD_TRANS,
+        PGM_REG_SEC_TRANS, PGM_REG_FIRST_TRANS
+    };
+
+    PTE_DPRINTF("%s: 0x%" PRIx64 "\n", __func__, entry);
+
+    origin = entry & _REGION_ENTRY_ORIGIN;
+    offs = (vaddr >> (17 + 11 * level / 4)) & 0x3ff8;
+
+    new_entry = ldq_phys(cs->as, origin + offs);
+    PTE_DPRINTF("%s: 0x%" PRIx64 " + 0x%" PRIx64 " => 0x%016" PRIx64 "\n",
+                __func__, origin, offs, new_entry);
+
+    if ((new_entry & _REGION_ENTRY_INV) != 0) {
+        DPRINTF("%s: invalid region\n", __func__);
+        trigger_page_fault(env, vaddr, pchks[level / 4], asc, rw, exc);
+        return -1;
+    }
+
+    if ((new_entry & _REGION_ENTRY_TYPE_MASK) != level) {
+        trigger_page_fault(env, vaddr, PGM_TRANS_SPEC, asc, rw, exc);
+        return -1;
+    }
+
+    if (level == _ASCE_TYPE_SEGMENT) {
+        return mmu_translate_segment(env, vaddr, asc, new_entry, raddr, flags,
+                                     rw, exc);
+    }
+
+    /* Check region table offset and length */
+    offs = (vaddr >> (28 + 11 * (level - 4) / 4)) & 3;
+    if (offs < ((new_entry & _REGION_ENTRY_TF) >> 6)
+        || offs > (new_entry & _REGION_ENTRY_LENGTH)) {
+        DPRINTF("%s: invalid offset or len (%lx)\n", __func__, new_entry);
+        trigger_page_fault(env, vaddr, pchks[level / 4 - 1], asc, rw, exc);
+        return -1;
+    }
+
+    if ((env->cregs[0] & CR0_EDAT) && (new_entry & _REGION_ENTRY_RO)) {
+        *flags &= ~PAGE_WRITE;
+    }
+
+    /* yet another region */
+    return mmu_translate_region(env, vaddr, asc, new_entry, level - 4,
+                                raddr, flags, rw, exc);
+}
+
+static int mmu_translate_asce(CPUS390XState *env, target_ulong vaddr,
+                              uint64_t asc, uint64_t asce, target_ulong *raddr,
+                              int *flags, int rw, bool exc)
+{
+    int level;
+    int r;
+
+    if (asce & _ASCE_REAL_SPACE) {
+        /* direct mapping */
+        *raddr = vaddr;
+        return 0;
+    }
+
+    level = asce & _ASCE_TYPE_MASK;
+    switch (level) {
+    case _ASCE_TYPE_REGION1:
+        if ((vaddr >> 62) > (asce & _ASCE_TABLE_LENGTH)) {
+            trigger_page_fault(env, vaddr, PGM_REG_FIRST_TRANS, asc, rw, exc);
+            return -1;
+        }
+        break;
+    case _ASCE_TYPE_REGION2:
+        if (vaddr & 0xffe0000000000000ULL) {
+            DPRINTF("%s: vaddr doesn't fit 0x%16" PRIx64
+                    " 0xffe0000000000000ULL\n", __func__, vaddr);
+            trigger_page_fault(env, vaddr, PGM_ASCE_TYPE, asc, rw, exc);
+            return -1;
+        }
+        if ((vaddr >> 51 & 3) > (asce & _ASCE_TABLE_LENGTH)) {
+            trigger_page_fault(env, vaddr, PGM_REG_SEC_TRANS, asc, rw, exc);
+            return -1;
+        }
+        break;
+    case _ASCE_TYPE_REGION3:
+        if (vaddr & 0xfffffc0000000000ULL) {
+            DPRINTF("%s: vaddr doesn't fit 0x%16" PRIx64
+                    " 0xfffffc0000000000ULL\n", __func__, vaddr);
+            trigger_page_fault(env, vaddr, PGM_ASCE_TYPE, asc, rw, exc);
+            return -1;
+        }
+        if ((vaddr >> 40 & 3) > (asce & _ASCE_TABLE_LENGTH)) {
+            trigger_page_fault(env, vaddr, PGM_REG_THIRD_TRANS, asc, rw, exc);
+            return -1;
+        }
+        break;
+    case _ASCE_TYPE_SEGMENT:
+        if (vaddr & 0xffffffff80000000ULL) {
+            DPRINTF("%s: vaddr doesn't fit 0x%16" PRIx64
+                    " 0xffffffff80000000ULL\n", __func__, vaddr);
+            trigger_page_fault(env, vaddr, PGM_ASCE_TYPE, asc, rw, exc);
+            return -1;
+        }
+        if ((vaddr >> 29 & 3) > (asce & _ASCE_TABLE_LENGTH)) {
+            trigger_page_fault(env, vaddr, PGM_SEGMENT_TRANS, asc, rw, exc);
+            return -1;
+        }
+        break;
+    }
+
+    r = mmu_translate_region(env, vaddr, asc, asce, level, raddr, flags, rw,
+                             exc);
+    if (rw == MMU_DATA_STORE && !(*flags & PAGE_WRITE)) {
+        trigger_prot_fault(env, vaddr, asc, rw, exc);
+        return -1;
+    }
+
+    return r;
+}
+
+/**
+ * Translate a virtual (logical) address into a physical (absolute) address.
+ * @param vaddr  the virtual address
+ * @param rw     0 = read, 1 = write, 2 = code fetch
+ * @param asc    address space control (one of the PSW_ASC_* modes)
+ * @param raddr  the translated address is stored to this pointer
+ * @param flags  the PAGE_READ/WRITE/EXEC flags are stored to this pointer
+ * @param exc    true = inject a program check if a fault occurred
+ * @return       0 if the translation was successful, -1 if a fault occurred
+ */
+int mmu_translate(CPUS390XState *env, target_ulong vaddr, int rw, uint64_t asc,
+                  target_ulong *raddr, int *flags, bool exc)
+{
+    static S390SKeysState *ss;
+    static S390SKeysClass *skeyclass;
+    int r = -1;
+    uint8_t key;
+
+    if (unlikely(!ss)) {
+        ss = s390_get_skeys_device();
+        skeyclass = S390_SKEYS_GET_CLASS(ss);
+    }
+
+    *flags = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
+    vaddr &= TARGET_PAGE_MASK;
+
+    if (!(env->psw.mask & PSW_MASK_DAT)) {
+        *raddr = vaddr;
+        r = 0;
+        goto out;
+    }
+
+    switch (asc) {
+    case PSW_ASC_PRIMARY:
+        PTE_DPRINTF("%s: asc=primary\n", __func__);
+        r = mmu_translate_asce(env, vaddr, asc, env->cregs[1], raddr, flags,
+                               rw, exc);
+        break;
+    case PSW_ASC_HOME:
+        PTE_DPRINTF("%s: asc=home\n", __func__);
+        r = mmu_translate_asce(env, vaddr, asc, env->cregs[13], raddr, flags,
+                               rw, exc);
+        break;
+    case PSW_ASC_SECONDARY:
+        PTE_DPRINTF("%s: asc=secondary\n", __func__);
+        /*
+         * Instruction: Primary
+         * Data: Secondary
+         */
+        if (rw == MMU_INST_FETCH) {
+            r = mmu_translate_asce(env, vaddr, PSW_ASC_PRIMARY, env->cregs[1],
+                                   raddr, flags, rw, exc);
+            *flags &= ~(PAGE_READ | PAGE_WRITE);
+        } else {
+            r = mmu_translate_asce(env, vaddr, PSW_ASC_SECONDARY, env->cregs[7],
+                                   raddr, flags, rw, exc);
+            *flags &= ~(PAGE_EXEC);
+        }
+        break;
+    case PSW_ASC_ACCREG:
+    default:
+        hw_error("guest switched to unknown asc mode\n");
+        break;
+    }
+
+ out:
+    /* Convert real address -> absolute address */
+    *raddr = mmu_real2abs(env, *raddr);
+
+    if (r == 0 && *raddr < ram_size) {
+        if (skeyclass->get_skeys(ss, *raddr / TARGET_PAGE_SIZE, 1, &key)) {
+            trace_get_skeys_nonzero(r);
+            return 0;
+        }
+
+        if (*flags & PAGE_READ) {
+            key |= SK_R;
+        }
+
+        if (*flags & PAGE_WRITE) {
+            key |= SK_C;
+        }
+
+        if (skeyclass->set_skeys(ss, *raddr / TARGET_PAGE_SIZE, 1, &key)) {
+            trace_set_skeys_nonzero(r);
+            return 0;
+        }
+    }
+
+    return r;
+}
+
+/**
+ * lowprot_enabled: Check whether low-address protection is enabled
+ */
+static bool lowprot_enabled(const CPUS390XState *env)
+{
+    if (!(env->cregs[0] & CR0_LOWPROT)) {
+        return false;
+    }
+    if (!(env->psw.mask & PSW_MASK_DAT)) {
+        return true;
+    }
+
+    /* Check the private-space control bit */
+    switch (env->psw.mask & PSW_MASK_ASC) {
+    case PSW_ASC_PRIMARY:
+        return !(env->cregs[1] & _ASCE_PRIVATE_SPACE);
+    case PSW_ASC_SECONDARY:
+        return !(env->cregs[7] & _ASCE_PRIVATE_SPACE);
+    case PSW_ASC_HOME:
+        return !(env->cregs[13] & _ASCE_PRIVATE_SPACE);
+    default:
+        /* We don't support access register mode */
+        error_report("unsupported addressing mode");
+        exit(1);
+    }
+}
+
+/**
+ * translate_pages: Translate a set of consecutive logical page addresses
+ * to absolute addresses
+ */
+static int translate_pages(S390CPU *cpu, vaddr addr, int nr_pages,
+                           target_ulong *pages, bool is_write)
+{
+    bool lowprot = is_write && lowprot_enabled(&cpu->env);
+    uint64_t asc = cpu->env.psw.mask & PSW_MASK_ASC;
+    CPUS390XState *env = &cpu->env;
+    int ret, i, pflags;
+
+    for (i = 0; i < nr_pages; i++) {
+        /* Low-address protection? */
+        if (lowprot && (addr < 512 || (addr >= 4096 && addr < 4096 + 512))) {
+            trigger_access_exception(env, PGM_PROTECTION, ILEN_LATER_INC, 0);
+            return -EACCES;
+        }
+        ret = mmu_translate(env, addr, is_write, asc, &pages[i], &pflags, true);
+        if (ret) {
+            return ret;
+        }
+        if (!address_space_access_valid(&address_space_memory, pages[i],
+                                        TARGET_PAGE_SIZE, is_write)) {
+            program_interrupt(env, PGM_ADDRESSING, 0);
+            return -EFAULT;
+        }
+        addr += TARGET_PAGE_SIZE;
+    }
+
+    return 0;
+}
+
+/**
+ * s390_cpu_virt_mem_rw:
+ * @laddr:     the logical start address
+ * @ar:        the access register number
+ * @hostbuf:   buffer in host memory. NULL = do only checks w/o copying
+ * @len:       length that should be transferred
+ * @is_write:  true = write, false = read
+ * Returns:    0 on success, non-zero if an exception occurred
+ *
+ * Copy from/to guest memory using logical addresses. Note that we inject a
+ * program interrupt in case there is an error while accessing the memory.
+ */
+int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
+                         int len, bool is_write)
+{
+    int currlen, nr_pages, i;
+    target_ulong *pages;
+    int ret;
+
+    if (kvm_enabled()) {
+        ret = kvm_s390_mem_op(cpu, laddr, ar, hostbuf, len, is_write);
+        if (ret >= 0) {
+            return ret;
+        }
+    }
+
+    nr_pages = (((laddr & ~TARGET_PAGE_MASK) + len - 1) >> TARGET_PAGE_BITS)
+               + 1;
+    pages = g_malloc(nr_pages * sizeof(*pages));
+
+    ret = translate_pages(cpu, laddr, nr_pages, pages, is_write);
+    if (ret == 0 && hostbuf != NULL) {
+        /* Copy data by stepping through the area page by page */
+        for (i = 0; i < nr_pages; i++) {
+            currlen = MIN(len, TARGET_PAGE_SIZE - (laddr % TARGET_PAGE_SIZE));
+            cpu_physical_memory_rw(pages[i] | (laddr & ~TARGET_PAGE_MASK),
+                                   hostbuf, currlen, is_write);
+            laddr += currlen;
+            hostbuf += currlen;
+            len -= currlen;
+        }
+    }
+
+    g_free(pages);
+    return ret;
+}