Commit bf011293 authored by john cooper's avatar john cooper Committed by Anthony Liguori
Browse files

Add serial number support for virtio_blk 



[brought forward to current qemu-kvm.git]

This patch implements the missing qemu logic to
interpret a '-drive .. serial=XYZ ..' flag for
a virtio_blk device.

The serial number string is contained in a
skeletal IDENTIFY DEVICE data structure and
this structure is made available to the guest
virtio_blk driver via pci i/o region 0.

Signed-off-by: default avatarjohn cooper <john.cooper@redhat.com>
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent 024589f1

hw/virtio-blk.c

+55 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ typedef struct VirtIOBlock 
    BlockDriverState *bs;

    VirtQueue *vq;

    void *rq;

    char serial_str[BLOCK_SERIAL_STRLEN + 1];

} VirtIOBlock;



static VirtIOBlock *to_virtio_blk(VirtIODevice *vdev)
@@ -32,6 +33,47 @@ static VirtIOBlock *to_virtio_blk(VirtIODevice *vdev) 
    return (VirtIOBlock *)vdev;

}



/* store identify data in little endian format

 */

static inline void put_le16(uint16_t *p, unsigned int v)

{

    *p = cpu_to_le16(v);

}



/* copy to *dst from *src, nul pad dst tail as needed to len bytes

 */

static inline void padstr(char *dst, const char *src, int len)

{

    while (len--)

        *dst++ = *src ? *src++ : '\0';

}



/* setup simulated identify data as appropriate for virtio block device

 *

 * ref: AT Attachment 8 - ATA/ATAPI Command Set (ATA8-ACS)

 */

static inline void virtio_identify_template(struct virtio_blk_config *bc)

{

    uint16_t *p = &bc->identify[0];

    uint64_t lba_sectors = bc->capacity;



    memset(p, 0, sizeof(bc->identify));

    put_le16(p + 0, 0x0);                            /* ATA device */

    padstr((char *)(p + 23), QEMU_VERSION, 8);       /* firmware revision */

    padstr((char *)(p + 27), "QEMU VIRT_BLK", 40);   /* model# */

    put_le16(p + 47, 0x80ff);                        /* max xfer 255 sectors */

    put_le16(p + 49, 0x0b00);                        /* support IORDY/LBA/DMA */

    put_le16(p + 59, 0x1ff);                         /* cur xfer 255 sectors */

    put_le16(p + 80, 0x1f0);                         /* support ATA8/7/6/5/4 */

    put_le16(p + 81, 0x16);

    put_le16(p + 82, 0x400);

    put_le16(p + 83, 0x400);

    put_le16(p + 100, lba_sectors);

    put_le16(p + 101, lba_sectors >> 16);

    put_le16(p + 102, lba_sectors >> 32);

    put_le16(p + 103, lba_sectors >> 48);

}



typedef struct VirtIOBlockReq

{

    VirtIOBlock *dev;
@@ -285,6 +327,8 @@ static void virtio_blk_reset(VirtIODevice *vdev) 
    qemu_aio_flush();

}



/* coalesce internal state, copy to pci i/o region 0

 */

static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)

{

    VirtIOBlock *s = to_virtio_blk(vdev);
@@ -301,11 +345,15 @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) 
    blkcfg.heads = heads;

    blkcfg.sectors = secs;

    blkcfg.size_max = 0;

    virtio_identify_template(&blkcfg);

    memcpy(&blkcfg.identify[VIRTIO_BLK_ID_SN], s->serial_str,

        VIRTIO_BLK_ID_SN_BYTES);

    memcpy(config, &blkcfg, sizeof(blkcfg));

}



static uint32_t virtio_blk_get_features(VirtIODevice *vdev)

{

    VirtIOBlock *s = to_virtio_blk(vdev);

    uint32_t features = 0;



    features |= (1 << VIRTIO_BLK_F_SEG_MAX);
@@ -313,6 +361,8 @@ static uint32_t virtio_blk_get_features(VirtIODevice *vdev) 
#ifdef __linux__

    features |= (1 << VIRTIO_BLK_F_SCSI);

#endif

    if (strcmp(s->serial_str, "0"))

        features |= 1 << VIRTIO_BLK_F_IDENTIFY;



    return features;

}
@@ -356,6 +406,7 @@ VirtIODevice *virtio_blk_init(DeviceState *dev) 
    int cylinders, heads, secs;

    static int virtio_blk_id;

    BlockDriverState *bs;

    char *ps;



    s = (VirtIOBlock *)virtio_common_init("virtio-blk", VIRTIO_ID_BLOCK,

                                          sizeof(struct virtio_blk_config),
@@ -367,6 +418,10 @@ VirtIODevice *virtio_blk_init(DeviceState *dev) 
    s->vdev.reset = virtio_blk_reset;

    s->bs = bs;

    s->rq = NULL;

    if (strlen(ps = (char *)drive_get_serial(bs)))

        strncpy(s->serial_str, ps, sizeof(s->serial_str));

    else

        snprintf(s->serial_str, sizeof(s->serial_str), "0");

    bs->private = dev;

    bdrv_guess_geometry(s->bs, &cylinders, &heads, &secs);

    bdrv_set_geometry_hint(s->bs, cylinders, heads, secs);

hw/virtio-blk.h

+7 −0
Original line number Diff line number Diff line
@@ -30,6 +30,11 @@ 
#define VIRTIO_BLK_F_RO         5       /* Disk is read-only */

#define VIRTIO_BLK_F_BLK_SIZE   6       /* Block size of disk is available*/

#define VIRTIO_BLK_F_SCSI       7       /* Supports scsi command passthru */

#define VIRTIO_BLK_F_IDENTIFY   8       /* ATA IDENTIFY supported */



#define VIRTIO_BLK_ID_LEN       256     /* length of identify u16 array */

#define VIRTIO_BLK_ID_SN        10      /* start of char * serial# */

#define VIRTIO_BLK_ID_SN_BYTES  20      /* length in bytes of serial# */



struct virtio_blk_config

{
@@ -39,6 +44,8 @@ struct virtio_blk_config 
    uint16_t cylinders;

    uint8_t heads;

    uint8_t sectors;

    uint32_t _blk_size;    /* structure pad, currently unused */

    uint16_t identify[VIRTIO_BLK_ID_LEN];

} __attribute__((packed));



/* These two define direction. */

sysemu.h

+3 −1
Original line number Diff line number Diff line
@@ -154,6 +154,8 @@ typedef enum { 
    BLOCK_ERR_STOP_ANY

} BlockInterfaceErrorAction;



#define BLOCK_SERIAL_STRLEN 20



typedef struct DriveInfo {

    BlockDriverState *bdrv;

    const char *devaddr;
@@ -163,7 +165,7 @@ typedef struct DriveInfo { 
    int used;

    int drive_opt_idx;

    BlockInterfaceErrorAction onerror;

    char serial[21];

    char serial[BLOCK_SERIAL_STRLEN + 1];

} DriveInfo;



#define MAX_IDE_DEVS	2