qapi: Convert memsave

Please, note that the QMP command has a new 'cpu-index' parameter.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

cpus.c

@@ -1136,3 +1136,50 @@ CpuInfoList *qmp_query_cpus(Error **errp)
 
     return head;
 }
+
+void qmp_memsave(int64_t addr, int64_t size, const char *filename,
+                 bool has_cpu, int64_t cpu_index, Error **errp)
+{
+    FILE *f;
+    uint32_t l;
+    CPUState *env;
+    uint8_t buf[1024];
+
+    if (!has_cpu) {
+        cpu_index = 0;
+    }
+
+    for (env = first_cpu; env; env = env->next_cpu) {
+        if (cpu_index == env->cpu_index) {
+            break;
+        }
+    }
+
+    if (env == NULL) {
+        error_set(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
+                  "a CPU number");
+        return;
+    }
+
+    f = fopen(filename, "wb");
+    if (!f) {
+        error_set(errp, QERR_OPEN_FILE_FAILED, filename);
+        return;
+    }
+
+    while (size != 0) {
+        l = sizeof(buf);
+        if (l > size)
+            l = size;
+        cpu_memory_rw_debug(env, addr, buf, l, 0);
+        if (fwrite(buf, 1, l, f) != l) {
+            error_set(errp, QERR_IO_ERROR);
+            goto exit;
+        }
+        addr += l;
+        size -= l;
+    }
+
+exit:
+    fclose(f);
+}

hmp-commands.hx

@@ -689,8 +689,7 @@ ETEXI
         .args_type  = "val:l,size:i,filename:s",
         .params     = "addr size file",
         .help       = "save to disk virtual memory dump starting at 'addr' of size 'size'",
-        .user_print = monitor_user_noop,
-        .mhandler.cmd_new = do_memory_save,
+        .mhandler.cmd = hmp_memsave,
     },
 
 STEXI

hmp.c

@@ -14,6 +14,14 @@
 #include "hmp.h"
 #include "qmp-commands.h"
 
+static void hmp_handle_error(Monitor *mon, Error **errp)
+{
+    if (error_is_set(errp)) {
+        monitor_printf(mon, "%s\n", error_get_pretty(*errp));
+        error_free(*errp);
+    }
+}
+
 void hmp_info_name(Monitor *mon)
 {
     NameInfo *info;
@@ -531,3 +539,14 @@ void hmp_cpu(Monitor *mon, const QDict *qdict)
         monitor_printf(mon, "invalid CPU index\n");
     }
 }
+
+void hmp_memsave(Monitor *mon, const QDict *qdict)
+{
+    uint32_t size = qdict_get_int(qdict, "size");
+    const char *filename = qdict_get_str(qdict, "filename");
+    uint64_t addr = qdict_get_int(qdict, "val");
+    Error *errp = NULL;
+
+    qmp_memsave(addr, size, filename, true, monitor_get_cpu_index(), &errp);
+    hmp_handle_error(mon, &errp);
+}

hmp.h

@@ -37,5 +37,6 @@ void hmp_stop(Monitor *mon, const QDict *qdict);
 void hmp_system_reset(Monitor *mon, const QDict *qdict);
 void hmp_system_powerdown(Monitor *mon, const QDict *qdict);
 void hmp_cpu(Monitor *mon, const QDict *qdict);
+void hmp_memsave(Monitor *mon, const QDict *qdict);
 
 #endif

monitor.c

@@ -1370,44 +1370,6 @@ static void do_print(Monitor *mon, const QDict *qdict)
     monitor_printf(mon, "\n");
 }
 
-static int do_memory_save(Monitor *mon, const QDict *qdict, QObject **ret_data)
-{
-    FILE *f;
-    uint32_t size = qdict_get_int(qdict, "size");
-    const char *filename = qdict_get_str(qdict, "filename");
-    target_long addr = qdict_get_int(qdict, "val");
-    uint32_t l;
-    CPUState *env;
-    uint8_t buf[1024];
-    int ret = -1;
-
-    env = mon_get_cpu();
-
-    f = fopen(filename, "wb");
-    if (!f) {
-        qerror_report(QERR_OPEN_FILE_FAILED, filename);
-        return -1;
-    }
-    while (size != 0) {
-        l = sizeof(buf);
-        if (l > size)
-            l = size;
-        cpu_memory_rw_debug(env, addr, buf, l, 0);
-        if (fwrite(buf, 1, l, f) != l) {
-            monitor_printf(mon, "fwrite() error in do_memory_save\n");
-            goto exit;
-        }
-        addr += l;
-        size -= l;
-    }
-
-    ret = 0;
-
-exit:
-    fclose(f);
-    return ret;
-}
-
 static int do_physical_memory_save(Monitor *mon, const QDict *qdict,
                                     QObject **ret_data)
 {

qapi-schema.json

@@ -901,3 +901,29 @@
 # Notes: Do not use this command.
 ##
 { 'command': 'cpu', 'data': {'index': 'int'} }
+
+##
+# @memsave:
+#
+# Save a portion of guest memory to a file.
+#
+# @val: the virtual address of the guest to start from
+#
+# @size: the size of memory region to save
+#
+# @filename: the file to save the memory to as binary data
+#
+# @cpu-index: #optional the index of the virtual CPU to use for translating the
+#                       virtual address (defaults to CPU 0)
+#
+# Returns: Nothing on success
+#          If @cpu is not a valid VCPU, InvalidParameterValue
+#          If @filename cannot be opened, OpenFileFailed
+#          If an I/O error occurs while writing the file, IOError
+#
+# Since: 0.14.0
+#
+# Notes: Errors were not reliably returned until 1.1
+##
+{ 'command': 'memsave',
+  'data': {'val': 'int', 'size': 'int', 'filename': 'str', '*cpu-index': 'int'} }

qmp-commands.hx

@@ -352,11 +352,8 @@ EQMP
 
     {
         .name       = "memsave",
-        .args_type  = "val:l,size:i,filename:s",
-        .params     = "addr size file",
-        .help       = "save to disk virtual memory dump starting at 'addr' of size 'size'",
-        .user_print = monitor_user_noop,
-        .mhandler.cmd_new = do_memory_save,
+        .args_type  = "val:l,size:i,filename:s,cpu:i?",
+        .mhandler.cmd_new = qmp_marshal_input_memsave,
     },
 
 SQMP
@@ -370,6 +367,7 @@ Arguments:
 - "val": the starting address (json-int)
 - "size": the memory size, in bytes (json-int)
 - "filename": file path (json-string)
+- "cpu": virtual CPU index (json-int, optional)
 
 Example:
 
@@ -379,8 +377,6 @@ Example:
                             "filename": "/tmp/virtual-mem-dump" } }
 <- { "return": {} }
 
-Note: Depends on the current CPU.
-
 EQMP
 
     {