ide.c

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    if (dma_buf_rw(bm, 0) == 0)
        goto eot;
#ifdef DEBUG_AIO
    printf("aio_write: sector_num=%lld n=%d\n", sector_num, n);
#endif
    bm->aiocb = bdrv_aio_write(s->bs, sector_num, s->io_buffer, n, 
                               ide_write_dma_cb, bm);
}

static void ide_sector_write_dma(IDEState *s)
{
    s->status = READY_STAT | SEEK_STAT | DRQ_STAT | BUSY_STAT;
    s->io_buffer_index = 0;
    s->io_buffer_size = 0;
    ide_dma_start(s, ide_write_dma_cb);
}

static void ide_atapi_cmd_ok(IDEState *s)
{
    s->error = 0;
    s->status = READY_STAT;
    s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
    ide_set_irq(s);
}

static void ide_atapi_cmd_error(IDEState *s, int sense_key, int asc)
{
#ifdef DEBUG_IDE_ATAPI
    printf("atapi_cmd_error: sense=0x%x asc=0x%x\n", sense_key, asc);
#endif
    s->error = sense_key << 4;
    s->status = READY_STAT | ERR_STAT;
    s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
    s->sense_key = sense_key;
    s->asc = asc;
    ide_set_irq(s);
}

static inline void cpu_to_ube16(uint8_t *buf, int val)
{
    buf[0] = val >> 8;
    buf[1] = val;
}

static inline void cpu_to_ube32(uint8_t *buf, unsigned int val)
{
    buf[0] = val >> 24;
    buf[1] = val >> 16;
    buf[2] = val >> 8;
    buf[3] = val;
}

static inline int ube16_to_cpu(const uint8_t *buf)
{
    return (buf[0] << 8) | buf[1];
}

static inline int ube32_to_cpu(const uint8_t *buf)
{
    return (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
}

static void lba_to_msf(uint8_t *buf, int lba)
{
    lba += 150;
    buf[0] = (lba / 75) / 60;
    buf[1] = (lba / 75) % 60;
    buf[2] = lba % 75;
}

static void cd_data_to_raw(uint8_t *buf, int lba)
{
    /* sync bytes */
    buf[0] = 0x00;
    memset(buf + 1, 0xff, 10);
    buf[11] = 0x00;
    buf += 12;
    /* MSF */
    lba_to_msf(buf, lba);
    buf[3] = 0x01; /* mode 1 data */
    buf += 4;
    /* data */
    buf += 2048;
    /* XXX: ECC not computed */
    memset(buf, 0, 288);
}

static int cd_read_sector(BlockDriverState *bs, int lba, uint8_t *buf, 
                           int sector_size)
{
    int ret;

    switch(sector_size) {
    case 2048:
        ret = bdrv_read(bs, (int64_t)lba << 2, buf, 4);
        break;
    case 2352:
        ret = bdrv_read(bs, (int64_t)lba << 2, buf + 16, 4);
        if (ret < 0)
            return ret;
        cd_data_to_raw(buf, lba);
        break;
    default:
        ret = -EIO;
        break;
    }
    return ret;
}

static void ide_atapi_io_error(IDEState *s, int ret)
{
    /* XXX: handle more errors */
    if (ret == -ENOMEDIUM) {
        ide_atapi_cmd_error(s, SENSE_NOT_READY, 
                            ASC_MEDIUM_NOT_PRESENT);
    } else {
        ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST, 
                            ASC_LOGICAL_BLOCK_OOR);
    }
}

/* The whole ATAPI transfer logic is handled in this function */
static void ide_atapi_cmd_reply_end(IDEState *s)
{
    int byte_count_limit, size, ret;
#ifdef DEBUG_IDE_ATAPI
    printf("reply: tx_size=%d elem_tx_size=%d index=%d\n", 
           s->packet_transfer_size,
           s->elementary_transfer_size,
           s->io_buffer_index);
#endif
    if (s->packet_transfer_size <= 0) {
        /* end of transfer */
        ide_transfer_stop(s);
        s->status = READY_STAT;
        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
        ide_set_irq(s);
#ifdef DEBUG_IDE_ATAPI
        printf("status=0x%x\n", s->status);
#endif
    } else {
        /* see if a new sector must be read */
        if (s->lba != -1 && s->io_buffer_index >= s->cd_sector_size) {
            ret = cd_read_sector(s->bs, s->lba, s->io_buffer, s->cd_sector_size);
            if (ret < 0) {
                ide_transfer_stop(s);
                ide_atapi_io_error(s, ret);
                return;
            }
            s->lba++;
            s->io_buffer_index = 0;
        }
        if (s->elementary_transfer_size > 0) {
            /* there are some data left to transmit in this elementary
               transfer */
            size = s->cd_sector_size - s->io_buffer_index;
            if (size > s->elementary_transfer_size)
                size = s->elementary_transfer_size;
            ide_transfer_start(s, s->io_buffer + s->io_buffer_index, 
                               size, ide_atapi_cmd_reply_end);
            s->packet_transfer_size -= size;
            s->elementary_transfer_size -= size;
            s->io_buffer_index += size;
        } else {
            /* a new transfer is needed */
            s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO;
            byte_count_limit = s->lcyl | (s->hcyl << 8);
#ifdef DEBUG_IDE_ATAPI
            printf("byte_count_limit=%d\n", byte_count_limit);
#endif
            if (byte_count_limit == 0xffff)
                byte_count_limit--;
            size = s->packet_transfer_size;
            if (size > byte_count_limit) {
                /* byte count limit must be even if this case */
                if (byte_count_limit & 1)
                    byte_count_limit--;
                size = byte_count_limit;
            }
            s->lcyl = size;
            s->hcyl = size >> 8;
            s->elementary_transfer_size = size;
            /* we cannot transmit more than one sector at a time */
            if (s->lba != -1) {
                if (size > (s->cd_sector_size - s->io_buffer_index))
                    size = (s->cd_sector_size - s->io_buffer_index);
            }
            ide_transfer_start(s, s->io_buffer + s->io_buffer_index, 
                               size, ide_atapi_cmd_reply_end);
            s->packet_transfer_size -= size;
            s->elementary_transfer_size -= size;
            s->io_buffer_index += size;
            ide_set_irq(s);
#ifdef DEBUG_IDE_ATAPI
            printf("status=0x%x\n", s->status);
#endif
        }
    }
}

/* send a reply of 'size' bytes in s->io_buffer to an ATAPI command */
static void ide_atapi_cmd_reply(IDEState *s, int size, int max_size)
{
    if (size > max_size)
        size = max_size;
    s->lba = -1; /* no sector read */
    s->packet_transfer_size = size;
    s->io_buffer_size = size;    /* dma: send the reply data as one chunk */
    s->elementary_transfer_size = 0;
    s->io_buffer_index = 0;

    if (s->atapi_dma) {
    	s->status = READY_STAT | DRQ_STAT;
	ide_dma_start(s, ide_atapi_cmd_read_dma_cb);
    } else {
    	s->status = READY_STAT;
    	ide_atapi_cmd_reply_end(s);
    }
}

/* start a CD-CDROM read command */
static void ide_atapi_cmd_read_pio(IDEState *s, int lba, int nb_sectors,
                                   int sector_size)
{
    s->lba = lba;
    s->packet_transfer_size = nb_sectors * sector_size;
    s->elementary_transfer_size = 0;
    s->io_buffer_index = sector_size;
    s->cd_sector_size = sector_size;

    s->status = READY_STAT;
    ide_atapi_cmd_reply_end(s);
}

/* ATAPI DMA support */

/* XXX: handle read errors */
static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret)
{
    BMDMAState *bm = opaque;
    IDEState *s = bm->ide_if;
    int data_offset, n;

    if (ret < 0) {
        ide_atapi_io_error(s, ret);
        goto eot;
    }

    if (s->io_buffer_size > 0) {
	/*
	 * For a cdrom read sector command (s->lba != -1),
	 * adjust the lba for the next s->io_buffer_size chunk
	 * and dma the current chunk.
	 * For a command != read (s->lba == -1), just transfer
	 * the reply data.
	 */
	if (s->lba != -1) {
	    if (s->cd_sector_size == 2352) {
		n = 1;
		cd_data_to_raw(s->io_buffer, s->lba);
	    } else {
		n = s->io_buffer_size >> 11;
	    }
	    s->lba += n;
	}
        s->packet_transfer_size -= s->io_buffer_size;
        if (dma_buf_rw(bm, 1) == 0)
            goto eot;
    }

    if (s->packet_transfer_size <= 0) {
        s->status = READY_STAT;
        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
        ide_set_irq(s);
    eot:
        bm->status &= ~BM_STATUS_DMAING;
        bm->status |= BM_STATUS_INT;
        bm->dma_cb = NULL;
        bm->ide_if = NULL;
        bm->aiocb = NULL;
        return;
    }
    
    s->io_buffer_index = 0;
    if (s->cd_sector_size == 2352) {
        n = 1;
        s->io_buffer_size = s->cd_sector_size;
        data_offset = 16;
    } else {
        n = s->packet_transfer_size >> 11;
        if (n > (MAX_MULT_SECTORS / 4))
            n = (MAX_MULT_SECTORS / 4);
        s->io_buffer_size = n * 2048;
        data_offset = 0;
    }
#ifdef DEBUG_AIO
    printf("aio_read_cd: lba=%u n=%d\n", s->lba, n);
#endif
    bm->aiocb = bdrv_aio_read(s->bs, (int64_t)s->lba << 2, 
                              s->io_buffer + data_offset, n * 4, 
                              ide_atapi_cmd_read_dma_cb, bm);
    if (!bm->aiocb) {
        /* Note: media not present is the most likely case */
        ide_atapi_cmd_error(s, SENSE_NOT_READY, 
                            ASC_MEDIUM_NOT_PRESENT);
        goto eot;
    }
}

/* start a CD-CDROM read command with DMA */
/* XXX: test if DMA is available */
static void ide_atapi_cmd_read_dma(IDEState *s, int lba, int nb_sectors,
                                   int sector_size)
{
    s->lba = lba;
    s->packet_transfer_size = nb_sectors * sector_size;
    s->io_buffer_index = 0;
    s->io_buffer_size = 0;
    s->cd_sector_size = sector_size;

    /* XXX: check if BUSY_STAT should be set */
    s->status = READY_STAT | DRQ_STAT | BUSY_STAT;
    ide_dma_start(s, ide_atapi_cmd_read_dma_cb);
}

static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors, 
                               int sector_size)
{
#ifdef DEBUG_IDE_ATAPI
    printf("read %s: LBA=%d nb_sectors=%d\n", s->atapi_dma ? "dma" : "pio",
	lba, nb_sectors);
#endif
    if (s->atapi_dma) {
        ide_atapi_cmd_read_dma(s, lba, nb_sectors, sector_size);
    } else {
        ide_atapi_cmd_read_pio(s, lba, nb_sectors, sector_size);
    }
}

static void ide_atapi_cmd(IDEState *s)
{
    const uint8_t *packet;
    uint8_t *buf;
    int max_len;

    packet = s->io_buffer;
    buf = s->io_buffer;
#ifdef DEBUG_IDE_ATAPI
    {
        int i;
        printf("ATAPI limit=0x%x packet:", s->lcyl | (s->hcyl << 8));
        for(i = 0; i < ATAPI_PACKET_SIZE; i++) {
            printf(" %02x", packet[i]);
        }
        printf("\n");
    }
#endif
    switch(s->io_buffer[0]) {
    case GPCMD_TEST_UNIT_READY:
        if (bdrv_is_inserted(s->bs)) {
            ide_atapi_cmd_ok(s);
        } else {
            ide_atapi_cmd_error(s, SENSE_NOT_READY, 
                                ASC_MEDIUM_NOT_PRESENT);
        }
        break;
    case GPCMD_MODE_SENSE_10:
        {
            int action, code;
            max_len = ube16_to_cpu(packet + 7);
            action = packet[2] >> 6;
            code = packet[2] & 0x3f;
            switch(action) {
            case 0: /* current values */
                switch(code) {
                case 0x01: /* error recovery */
                    cpu_to_ube16(&buf[0], 16 + 6);
                    buf[2] = 0x70;
                    buf[3] = 0;
                    buf[4] = 0;
                    buf[5] = 0;
                    buf[6] = 0;
                    buf[7] = 0;

                    buf[8] = 0x01;
                    buf[9] = 0x06;
                    buf[10] = 0x00;
                    buf[11] = 0x05;
                    buf[12] = 0x00;
                    buf[13] = 0x00;
                    buf[14] = 0x00;
                    buf[15] = 0x00;
                    ide_atapi_cmd_reply(s, 16, max_len);
                    break;
                case 0x2a:
                    cpu_to_ube16(&buf[0], 28 + 6);
                    buf[2] = 0x70;
                    buf[3] = 0;
                    buf[4] = 0;
                    buf[5] = 0;
                    buf[6] = 0;
                    buf[7] = 0;

                    buf[8] = 0x2a;
                    buf[9] = 0x12;
                    buf[10] = 0x00;
                    buf[11] = 0x00;
                    
                    buf[12] = 0x70;
                    buf[13] = 3 << 5;
                    buf[14] = (1 << 0) | (1 << 3) | (1 << 5);
                    if (bdrv_is_locked(s->bs))
                        buf[6] |= 1 << 1;
                    buf[15] = 0x00;
                    cpu_to_ube16(&buf[16], 706);
                    buf[18] = 0;
                    buf[19] = 2;
                    cpu_to_ube16(&buf[20], 512);
                    cpu_to_ube16(&buf[22], 706);
                    buf[24] = 0;
                    buf[25] = 0;
                    buf[26] = 0;
                    buf[27] = 0;
                    ide_atapi_cmd_reply(s, 28, max_len);
                    break;
                default:
                    goto error_cmd;
                }