AHCI: pretty-print FIS to buffer instead of stderr

The current FIS printing routines dump the FIS to screen. adjust this
such that it dumps to buffer instead, then use this ability to have
FIS dump mechanisms via trace-events instead of compiled defines.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20170901001502.29915-9-jsnow@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

hw/ide/ahci.c

@@ -644,20 +644,21 @@ static void ahci_reset_port(AHCIState *s, int port)
     ahci_init_d2h(d);
 }
 
-static void debug_print_fis(uint8_t *fis, int cmd_len)
+/* Buffer pretty output based on a raw FIS structure. */
+static char *ahci_pretty_buffer_fis(uint8_t *fis, int cmd_len)
 {
-#if DEBUG_AHCI
     int i;
+    GString *s = g_string_new("FIS:");
 
-    fprintf(stderr, "fis:");
     for (i = 0; i < cmd_len; i++) {
         if ((i & 0xf) == 0) {
-            fprintf(stderr, "\n%02x:",i);
+            g_string_append_printf(s, "\n0x%02x: ", i);
         }
-        fprintf(stderr, "%02x ",fis[i]);
+        g_string_append_printf(s, "%02x ", fis[i]);
     }
-    fprintf(stderr, "\n");
-#endif
+    g_string_append_c(s, '\n');
+
+    return g_string_free(s, FALSE);
 }
 
 static bool ahci_map_fis_address(AHCIDevice *ad)
@@ -1201,7 +1202,11 @@ static void handle_reg_h2d_fis(AHCIState *s, int port,
      * table to ide_state->io_buffer */
     if (opts & AHCI_CMD_ATAPI) {
         memcpy(ide_state->io_buffer, &cmd_fis[AHCI_COMMAND_TABLE_ACMD], 0x10);
-        debug_print_fis(ide_state->io_buffer, 0x10);
+        if (trace_event_get_state_backends(TRACE_HANDLE_REG_H2D_FIS_DUMP)) {
+            char *pretty_fis = ahci_pretty_buffer_fis(ide_state->io_buffer, 0x10);
+            trace_handle_reg_h2d_fis_dump(s, port, pretty_fis);
+            g_free(pretty_fis);
+        }
         s->dev[port].done_atapi_packet = false;
         /* XXX send PIO setup FIS */
     }
@@ -1256,8 +1261,11 @@ static int handle_cmd(AHCIState *s, int port, uint8_t slot)
         trace_handle_cmd_badmap(s, port, cmd_len);
         goto out;
     }
-    debug_print_fis(cmd_fis, 0x80);
-
+    if (trace_event_get_state_backends(TRACE_HANDLE_CMD_FIS_DUMP)) {
+        char *pretty_fis = ahci_pretty_buffer_fis(cmd_fis, 0x80);
+        trace_handle_cmd_fis_dump(s, port, pretty_fis);
+        g_free(pretty_fis);
+    }
     switch (cmd_fis[0]) {
         case SATA_FIS_TYPE_REGISTER_H2D:
             handle_reg_h2d_fis(s, port, slot, cmd_fis);

hw/ide/trace-events

@@ -105,3 +105,7 @@ ahci_cmd_done(void *s, int port) "ahci(%p)[%d]: cmd done"
 ahci_reset(void *s) "ahci(%p): HBA reset"
 allwinner_ahci_mem_read(void *s, void *a, uint64_t addr, uint64_t val, unsigned size) "ahci(%p): read a=%p addr=0x%"HWADDR_PRIx" val=0x%"PRIx64", size=%d"
 allwinner_ahci_mem_write(void *s, void *a, uint64_t addr, uint64_t val, unsigned size) "ahci(%p): write a=%p addr=0x%"HWADDR_PRIx" val=0x%"PRIx64", size=%d"
+
+# Warning: Verbose
+handle_reg_h2d_fis_dump(void *s, int port, const char *fis) "ahci(%p)[%d]: %s"
+handle_cmd_fis_dump(void *s, int port, const char *fis) "ahci(%p)[%d]: %s"