[Qemu-devel] [PATCH v3 3/5] atapi: GESN: Use structs for commonly-used field types

[Amit Shah <amit.shah@redhat.com>]

Instead of using magic numbers, use structs that are more descriptive of
the fields being used.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 hw/ide/core.c |   22 +++++++++++++++++-----
 1 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/hw/ide/core.c b/hw/ide/core.c
index 5b64676..e838990 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -1088,11 +1088,23 @@ static void handle_get_event_status_notification(IDEState *s,
                                                  uint8_t *buf,
                                                  const uint8_t *packet)
 {
-    unsigned int max_len;
-
-    max_len = ube16_to_cpu(packet + 7);
-
-    if (!(packet[1] & 0x01)) { /* asynchronous mode */
+    struct {
+        uint8_t opcode;
+        uint8_t polled;        /* lsb bit is polled; others are reserved */
+        uint8_t reserved2[2];
+        uint8_t class;
+        uint8_t reserved3[2];
+        uint16_t len;
+        uint8_t control;
+    } __attribute__((packed)) *gesn_cdb;
+
+    unsigned int max_len, used_len;
+
+    gesn_cdb = (void *)packet;
+    max_len = be16_to_cpu(gesn_cdb->len);
+
+    /* It is fine by the MMC spec to not support async mode operations */
+    if (!(gesn_cdb->polled & 0x01)) { /* asynchronous mode */
         /* Only polling is supported, asynchronous mode is not. */
         ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                             ASC_INV_FIELD_IN_CMD_PACKET);
-- 
1.7.4.2