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authorPhilippe Mathieu-Daudé <philmd@linaro.org>2023-10-04 11:06:28 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2023-10-08 21:08:08 +0200
commit8d7f2e767d8cd058c817dbe31430b89f2e11535d (patch)
tree5b7c25cddf7e6c1b9dfc93c5169541e8c14e2901 /system/watchpoint.c
parent01c85e60a4d0675f0ad203fe1fe119381e7ad15b (diff)
system: Rename softmmu/ directory as system/
The softmmu/ directory contains files specific to system emulation. Rename it as system/. Update meson rules, the MAINTAINERS file and all the documentation and comments. Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> Message-ID: <20231004090629.37473-14-philmd@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@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 */