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authorStefan Hajnoczi <stefanha@redhat.com>2023-10-09 10:11:17 -0400
committerStefan Hajnoczi <stefanha@redhat.com>2023-10-09 10:11:18 -0400
commit1527c6b6fa6c6775523287e33f78b41afc7ba46c (patch)
treee245ed1f0f1856b800b391e22da9d09b21950540 /system/watchpoint.c
parentf7294103560260ff09ffdf316cf6ba6d4e368d85 (diff)
parent912eef205ae9ccfd477c343a51a7c2dcfae2ba43 (diff)
downloadfocaccia-qemu-1527c6b6fa6c6775523287e33f78b41afc7ba46c.tar.gz
focaccia-qemu-1527c6b6fa6c6775523287e33f78b41afc7ba46c.zip
Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging
* util/log: re-allow switching away from stderr log file
* finish audio configuration rework
* cleanup HVF stubs
* remove more mentions of softmmu

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* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (25 commits)
  audio, qtest: get rid of QEMU_AUDIO_DRV
  audio: reintroduce default audio backend for VNC
  audio: do not use first -audiodev as default audio device
  audio: extend -audio to allow creating a default backend
  audio: extract audio_define_default
  audio: disable default backends if -audio/-audiodev is used
  audio: error hints need a trailing \n
  cutils: squelch compiler warnings with custom paths
  configure: change $softmmu to $system
  system: Rename softmmu/ directory as system/
  meson: Rename target_softmmu_arch -> target_system_arch
  meson: Rename softmmu_mods -> system_mods
  target/i386: Rename i386_softmmu_kvm_ss -> i386_kvm_ss
  semihosting: Rename softmmu_FOO_user() -> uaccess_FOO_user()
  gdbstub: Rename 'softmmu' -> 'system'
  accel: Rename accel_softmmu* -> accel_system*
  tcg: Correct invalid mentions of 'softmmu' by 'system-mode'
  fuzz: Correct invalid mentions of 'softmmu' by 'system'
  cpu: Correct invalid mentions of 'softmmu' by 'system-mode'
  travis-ci: Correct invalid mentions of 'softmmu' by 'system'
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'system/watchpoint.c')
-rw-r--r--system/watchpoint.c226
1 files changed, 226 insertions, 0 deletions
diff --git a/system/watchpoint.c b/system/watchpoint.c
new file mode 100644
index 0000000000..45d1f12faf
--- /dev/null
+++ b/system/watchpoint.c
@@ -0,0 +1,226 @@
+/*
+ * CPU watchpoints
+ *
+ *  Copyright (c) 2003 Fabrice Bellard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "qemu/error-report.h"
+#include "exec/exec-all.h"
+#include "exec/translate-all.h"
+#include "sysemu/tcg.h"
+#include "sysemu/replay.h"
+#include "hw/core/tcg-cpu-ops.h"
+#include "hw/core/cpu.h"
+
+/* Add a watchpoint.  */
+int cpu_watchpoint_insert(CPUState *cpu, vaddr addr, vaddr len,
+                          int flags, CPUWatchpoint **watchpoint)
+{
+    CPUWatchpoint *wp;
+    vaddr in_page;
+
+    /* forbid ranges which are empty or run off the end of the address space */
+    if (len == 0 || (addr + len - 1) < addr) {
+        error_report("tried to set invalid watchpoint at %"
+                     VADDR_PRIx ", len=%" VADDR_PRIu, addr, len);
+        return -EINVAL;
+    }
+    wp = g_malloc(sizeof(*wp));
+
+    wp->vaddr = addr;
+    wp->len = len;
+    wp->flags = flags;
+
+    /* keep all GDB-injected watchpoints in front */
+    if (flags & BP_GDB) {
+        QTAILQ_INSERT_HEAD(&cpu->watchpoints, wp, entry);
+    } else {
+        QTAILQ_INSERT_TAIL(&cpu->watchpoints, wp, entry);
+    }
+
+    in_page = -(addr | TARGET_PAGE_MASK);
+    if (len <= in_page) {
+        tlb_flush_page(cpu, addr);
+    } else {
+        tlb_flush(cpu);
+    }
+
+    if (watchpoint) {
+        *watchpoint = wp;
+    }
+    return 0;
+}
+
+/* Remove a specific watchpoint.  */
+int cpu_watchpoint_remove(CPUState *cpu, vaddr addr, vaddr len,
+                          int flags)
+{
+    CPUWatchpoint *wp;
+
+    QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
+        if (addr == wp->vaddr && len == wp->len
+                && flags == (wp->flags & ~BP_WATCHPOINT_HIT)) {
+            cpu_watchpoint_remove_by_ref(cpu, wp);
+            return 0;
+        }
+    }
+    return -ENOENT;
+}
+
+/* Remove a specific watchpoint by reference.  */
+void cpu_watchpoint_remove_by_ref(CPUState *cpu, CPUWatchpoint *watchpoint)
+{
+    QTAILQ_REMOVE(&cpu->watchpoints, watchpoint, entry);
+
+    tlb_flush_page(cpu, watchpoint->vaddr);
+
+    g_free(watchpoint);
+}
+
+/* Remove all matching watchpoints.  */
+void cpu_watchpoint_remove_all(CPUState *cpu, int mask)
+{
+    CPUWatchpoint *wp, *next;
+
+    QTAILQ_FOREACH_SAFE(wp, &cpu->watchpoints, entry, next) {
+        if (wp->flags & mask) {
+            cpu_watchpoint_remove_by_ref(cpu, wp);
+        }
+    }
+}
+
+#ifdef CONFIG_TCG
+
+/*
+ * Return true if this watchpoint address matches the specified
+ * access (ie the address range covered by the watchpoint overlaps
+ * partially or completely with the address range covered by the
+ * access).
+ */
+static inline bool watchpoint_address_matches(CPUWatchpoint *wp,
+                                              vaddr addr, vaddr len)
+{
+    /*
+     * We know the lengths are non-zero, but a little caution is
+     * required to avoid errors in the case where the range ends
+     * exactly at the top of the address space and so addr + len
+     * wraps round to zero.
+     */
+    vaddr wpend = wp->vaddr + wp->len - 1;
+    vaddr addrend = addr + len - 1;
+
+    return !(addr > wpend || wp->vaddr > addrend);
+}
+
+/* Return flags for watchpoints that match addr + prot.  */
+int cpu_watchpoint_address_matches(CPUState *cpu, vaddr addr, vaddr len)
+{
+    CPUWatchpoint *wp;
+    int ret = 0;
+
+    QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
+        if (watchpoint_address_matches(wp, addr, len)) {
+            ret |= wp->flags;
+        }
+    }
+    return ret;
+}
+
+/* Generate a debug exception if a watchpoint has been hit.  */
+void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len,
+                          MemTxAttrs attrs, int flags, uintptr_t ra)
+{
+    CPUClass *cc = CPU_GET_CLASS(cpu);
+    CPUWatchpoint *wp;
+
+    assert(tcg_enabled());
+    if (cpu->watchpoint_hit) {
+        /*
+         * We re-entered the check after replacing the TB.
+         * Now raise the debug interrupt so that it will
+         * trigger after the current instruction.
+         */
+        qemu_mutex_lock_iothread();
+        cpu_interrupt(cpu, CPU_INTERRUPT_DEBUG);
+        qemu_mutex_unlock_iothread();
+        return;
+    }
+
+    if (cc->tcg_ops->adjust_watchpoint_address) {
+        /* this is currently used only by ARM BE32 */
+        addr = cc->tcg_ops->adjust_watchpoint_address(cpu, addr, len);
+    }
+
+    assert((flags & ~BP_MEM_ACCESS) == 0);
+    QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
+        int hit_flags = wp->flags & flags;
+
+        if (hit_flags && watchpoint_address_matches(wp, addr, len)) {
+            if (replay_running_debug()) {
+                /*
+                 * replay_breakpoint reads icount.
+                 * Force recompile to succeed, because icount may
+                 * be read only at the end of the block.
+                 */
+                if (!cpu->neg.can_do_io) {
+                    /* Force execution of one insn next time.  */
+                    cpu->cflags_next_tb = 1 | CF_LAST_IO | CF_NOIRQ
+                                          | curr_cflags(cpu);
+                    cpu_loop_exit_restore(cpu, ra);
+                }
+                /*
+                 * Don't process the watchpoints when we are
+                 * in a reverse debugging operation.
+                 */
+                replay_breakpoint();
+                return;
+            }
+
+            wp->flags |= hit_flags << BP_HIT_SHIFT;
+            wp->hitaddr = MAX(addr, wp->vaddr);
+            wp->hitattrs = attrs;
+
+            if (wp->flags & BP_CPU
+                && cc->tcg_ops->debug_check_watchpoint
+                && !cc->tcg_ops->debug_check_watchpoint(cpu, wp)) {
+                wp->flags &= ~BP_WATCHPOINT_HIT;
+                continue;
+            }
+            cpu->watchpoint_hit = wp;
+
+            mmap_lock();
+            /* This call also restores vCPU state */
+            tb_check_watchpoint(cpu, ra);
+            if (wp->flags & BP_STOP_BEFORE_ACCESS) {
+                cpu->exception_index = EXCP_DEBUG;
+                mmap_unlock();
+                cpu_loop_exit(cpu);
+            } else {
+                /* Force execution of one insn next time.  */
+                cpu->cflags_next_tb = 1 | CF_LAST_IO | CF_NOIRQ
+                                      | curr_cflags(cpu);
+                mmap_unlock();
+                cpu_loop_exit_noexc(cpu);
+            }
+        } else {
+            wp->flags &= ~BP_WATCHPOINT_HIT;
+        }
+    }
+}
+
+#endif /* CONFIG_TCG */