Re: [Qemu-devel] [PATCH] ide: fix ATAPI read drive structure command (v3)

[Alex Williamson]

On Tue, 2008-06-03 at 11:59 -0500, Anthony Liguori wrote:
> Can you send this as an attachment or inlined as plain text?

Hmm, shows up as plain text in the archives, although there is a strange
character in front of the patch title.  Here it is again.  Thanks,

        Alex

Fix ATAPI read drive structure command

Previous version ignored the allocation length parameter and read the
format byte from the wrong location.  Re-implement to support the full
requirements for DVD-ROM and allow for easy extension later.

Signed-off-by: Alex Williamson <address@hidden>
--

--- a/trunk/hw/ide.c    2008-06-02 16:37:12.000000000 -0600
+++ b/trunk/hw/ide.c    2008-06-02 16:40:11.000000000 -0600
@@ -351,6 +351,7 @@
 #define ASC_ILLEGAL_OPCODE                   0x20
 #define ASC_LOGICAL_BLOCK_OOR                0x21
 #define ASC_INV_FIELD_IN_CMD_PACKET          0x24
+#define ASC_INCOMPATIBLE_FORMAT              0x30
 #define ASC_MEDIUM_NOT_PRESENT               0x3a
 #define ASC_SAVING_PARAMETERS_NOT_SUPPORTED  0x39
 
@@ -434,6 +435,22 @@
     int media_changed;
 } IDEState;
 
+/* XXX: DVDs that could fit on a CD will be reported as a CD */
+static inline int media_present(IDEState *s)
+{
+    return (s->nb_sectors > 0);
+}
+
+static inline int media_is_dvd(IDEState *s)
+{
+    return (media_present(s) && s->nb_sectors > CD_MAX_SECTORS);
+}
+
+static inline int media_is_cd(IDEState *s)
+{
+    return (media_present(s) && s->nb_sectors <= CD_MAX_SECTORS);
+}
+
 #define BM_STATUS_DMAING 0x01
 #define BM_STATUS_ERROR  0x02
 #define BM_STATUS_INT    0x04
@@ -1364,6 +1381,93 @@
     return 4;
 }
 
+static int ide_dvd_read_structure(IDEState *s, int format,
+                                  const uint8_t *packet, uint8_t *buf)
+{
+    switch (format) {
+        case 0x0: /* Physical format information */
+            {
+                int layer = packet[6];
+                uint64_t total_sectors;
+
+                if (layer != 0)
+                    return -ASC_INV_FIELD_IN_CMD_PACKET;
+
+                bdrv_get_geometry(s->bs, &total_sectors);
+                total_sectors >>= 2;
+                if (total_sectors == 0)
+                    return -ASC_MEDIUM_NOT_PRESENT;
+
+                buf[4] = 1;   /* DVD-ROM, part version 1 */
+                buf[5] = 0xf; /* 120mm disc, minimum rate unspecified */
+                buf[6] = 1;   /* one layer, read-only (per MMC-2 spec) */
+                buf[7] = 0;   /* default densities */
+
+                /* FIXME: 0x30000 per spec? */
+                cpu_to_ube32(buf + 8, 0); /* start sector */
+                cpu_to_ube32(buf + 12, total_sectors - 1); /* end sector */
+                cpu_to_ube32(buf + 16, total_sectors - 1); /* l0 end sector */
+
+                /* Size of buffer, not including 2 byte size field */
+                cpu_to_be16wu((uint16_t *)buf, 2048 + 2);
+
+                /* 2k data + 4 byte header */
+                return (2048 + 4);
+            }
+
+        case 0x01: /* DVD copyright information */
+            buf[4] = 0; /* no copyright data */
+            buf[5] = 0; /* no region restrictions */
+
+            /* Size of buffer, not including 2 byte size field */
+            cpu_to_be16wu((uint16_t *)buf, 4 + 2);
+
+            /* 4 byte header + 4 byte data */
+            return (4 + 4);
+
+        case 0x03: /* BCA information - invalid field for no BCA info */
+            return -ASC_INV_FIELD_IN_CMD_PACKET;
+
+        case 0x04: /* DVD disc manufacturing information */
+            /* Size of buffer, not including 2 byte size field */
+            cpu_to_be16wu((uint16_t *)buf, 2048 + 2);
+
+            /* 2k data + 4 byte header */
+            return (2048 + 4);
+
+        case 0xff:
+            /*
+             * This lists all the command capabilities above.  Add new ones
+             * in order and update the length and buffer return values.
+             */
+
+            buf[4] = 0x00; /* Physical format */
+            buf[5] = 0x40; /* Not writable, is readable */
+            cpu_to_be16wu((uint16_t *)(buf + 6), 2048 + 4);
+
+            buf[8] = 0x01; /* Copyright info */
+            buf[9] = 0x40; /* Not writable, is readable */
+            cpu_to_be16wu((uint16_t *)(buf + 10), 4 + 4);
+
+            buf[12] = 0x03; /* BCA info */
+            buf[13] = 0x40; /* Not writable, is readable */
+            cpu_to_be16wu((uint16_t *)(buf + 14), 188 + 4);
+
+            buf[16] = 0x04; /* Manufacturing info */
+            buf[17] = 0x40; /* Not writable, is readable */
+            cpu_to_be16wu((uint16_t *)(buf + 18), 2048 + 4);
+
+            /* Size of buffer, not including 2 byte size field */
+            cpu_to_be16wu((uint16_t *)buf, 16 + 2);
+
+            /* data written + 4 byte header */
+            return (16 + 4);
+
+        default: /* TODO: formats beyond DVD-ROM requires */
+            return -ASC_INV_FIELD_IN_CMD_PACKET;
+    }
+}
+
 static void ide_atapi_cmd(IDEState *s)
 {
     const uint8_t *packet;
@@ -1651,42 +1755,42 @@
     case GPCMD_READ_DVD_STRUCTURE:
         {
             int media = packet[1];
-            int layer = packet[6];
-            int format = packet[2];
-            uint64_t total_sectors;
+            int format = packet[7];
+            int ret;
 
-            if (media != 0 || layer != 0)
-            {
+            max_len = ube16_to_cpu(packet + 8);
+
+            if (format < 0xff && media_is_cd(s)) {
                 ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
-                                    ASC_INV_FIELD_IN_CMD_PACKET);
+                                    ASC_INCOMPATIBLE_FORMAT);
+                break;
             }
 
+            memset(buf, 0, max_len > IDE_DMA_BUF_SECTORS * 512 + 4 ?
+                   IDE_DMA_BUF_SECTORS * 512 + 4 : max_len);
+
             switch (format) {
-                case 0:
-                    bdrv_get_geometry(s->bs, &total_sectors);
-                    total_sectors >>= 2;
-                    if (total_sectors == 0) {
-                        ide_atapi_cmd_error(s, SENSE_NOT_READY,
-                                            ASC_MEDIUM_NOT_PRESENT);
+                case 0x00 ... 0x7f:
+                case 0xff:
+                    if (media == 0) {
+                        ret = ide_dvd_read_structure(s, format, packet, buf);
+
+                        if (ret < 0)
+                            ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST, 
-ret);
+                        else
+                            ide_atapi_cmd_reply(s, ret, max_len);
+
                         break;
                     }
+                    /* TODO: BD support, fall through for now */
 
-                    memset(buf, 0, 2052);
-
-                    buf[4] = 1;   // DVD-ROM, part version 1
-                    buf[5] = 0xf; // 120mm disc, maximum rate unspecified
-                    buf[6] = 0;   // one layer, embossed data
-                    buf[7] = 0;
-
-                    cpu_to_ube32(buf + 8, 0);
-                    cpu_to_ube32(buf + 12, total_sectors - 1);
-                    cpu_to_ube32(buf + 16, total_sectors - 1);
-
-                    cpu_to_be16wu((uint16_t *)buf, 2048 + 4);
-
-                    ide_atapi_cmd_reply(s, 2048 + 3, 2048 + 4);
-                    break;
-
+                /* Generic disk structures */
+                case 0x80: /* TODO: AACS volume identifier */
+                case 0x81: /* TODO: AACS media serial number */
+                case 0x82: /* TODO: AACS media identifier */
+                case 0x83: /* TODO: AACS media key block */
+                case 0x90: /* TODO: List of recognized format layers */
+                case 0xc0: /* TODO: Write protection status */
                 default:
                     ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                                         ASC_INV_FIELD_IN_CMD_PACKET);
@@ -1741,16 +1845,11 @@
             /* 
              * the number of sectors from the media tells us which profile
              * to use as current.  0 means there is no media
-             *
-             * XXX: fails to detect correctly DVDs with less data burned
-             *      than what a CD can hold
              */
-            if (s -> nb_sectors) {
-                if (s -> nb_sectors > CD_MAX_SECTORS)
-                    cpu_to_ube16(buf + 6, MMC_PROFILE_DVD_ROM);
-                else
-                    cpu_to_ube16(buf + 6, MMC_PROFILE_CD_ROM);
-            }
+            if (media_is_dvd(s))
+                cpu_to_ube16(buf + 6, MMC_PROFILE_DVD_ROM);
+            else if (media_is_cd(s))
+                cpu_to_ube16(buf + 6, MMC_PROFILE_CD_ROM);
 
             buf[10] = 0x02 | 0x01; /* persistent and current */
             len = 12; /* headers: 8 + 4 */