diff options
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/xen-blkfront.c | 76 |
1 files changed, 55 insertions, 21 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 3ca643cafccd..bff602ccccf3 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -105,15 +105,17 @@ static DEFINE_SPINLOCK(blkif_io_lock); #define GRANT_INVALID_REF 0 #define PARTS_PER_DISK 16 +#define PARTS_PER_EXT_DISK 256 #define BLKIF_MAJOR(dev) ((dev)>>8) #define BLKIF_MINOR(dev) ((dev) & 0xff) -#define DEV_NAME "xvd" /* name in /dev */ +#define EXT_SHIFT 28 +#define EXTENDED (1<<EXT_SHIFT) +#define VDEV_IS_EXTENDED(dev) ((dev)&(EXTENDED)) +#define BLKIF_MINOR_EXT(dev) ((dev)&(~EXTENDED)) -/* Information about our VBDs. */ -#define MAX_VBDS 64 -static LIST_HEAD(vbds_list); +#define DEV_NAME "xvd" /* name in /dev */ static int get_id_from_freelist(struct blkfront_info *info) { @@ -386,31 +388,60 @@ static int xlvbd_barrier(struct blkfront_info *info) } -static int xlvbd_alloc_gendisk(int minor, blkif_sector_t capacity, - int vdevice, u16 vdisk_info, u16 sector_size, - struct blkfront_info *info) +static int xlvbd_alloc_gendisk(blkif_sector_t capacity, + struct blkfront_info *info, + u16 vdisk_info, u16 sector_size) { struct gendisk *gd; int nr_minors = 1; int err = -ENODEV; + unsigned int offset; + int minor; + int nr_parts; BUG_ON(info->gd != NULL); BUG_ON(info->rq != NULL); - if ((minor % PARTS_PER_DISK) == 0) - nr_minors = PARTS_PER_DISK; + if ((info->vdevice>>EXT_SHIFT) > 1) { + /* this is above the extended range; something is wrong */ + printk(KERN_WARNING "blkfront: vdevice 0x%x is above the extended range; ignoring\n", info->vdevice); + return -ENODEV; + } + + if (!VDEV_IS_EXTENDED(info->vdevice)) { + minor = BLKIF_MINOR(info->vdevice); + nr_parts = PARTS_PER_DISK; + } else { + minor = BLKIF_MINOR_EXT(info->vdevice); + nr_parts = PARTS_PER_EXT_DISK; + } + + if ((minor % nr_parts) == 0) + nr_minors = nr_parts; gd = alloc_disk(nr_minors); if (gd == NULL) goto out; - if (nr_minors > 1) - sprintf(gd->disk_name, "%s%c", DEV_NAME, - 'a' + minor / PARTS_PER_DISK); - else - sprintf(gd->disk_name, "%s%c%d", DEV_NAME, - 'a' + minor / PARTS_PER_DISK, - minor % PARTS_PER_DISK); + offset = minor / nr_parts; + + if (nr_minors > 1) { + if (offset < 26) + sprintf(gd->disk_name, "%s%c", DEV_NAME, 'a' + offset); + else + sprintf(gd->disk_name, "%s%c%c", DEV_NAME, + 'a' + ((offset / 26)-1), 'a' + (offset % 26)); + } else { + if (offset < 26) + sprintf(gd->disk_name, "%s%c%d", DEV_NAME, + 'a' + offset, + minor & (nr_parts - 1)); + else + sprintf(gd->disk_name, "%s%c%c%d", DEV_NAME, + 'a' + ((offset / 26) - 1), + 'a' + (offset % 26), + minor & (nr_parts - 1)); + } gd->major = XENVBD_MAJOR; gd->first_minor = minor; @@ -699,8 +730,13 @@ static int blkfront_probe(struct xenbus_device *dev, err = xenbus_scanf(XBT_NIL, dev->nodename, "virtual-device", "%i", &vdevice); if (err != 1) { - xenbus_dev_fatal(dev, err, "reading virtual-device"); - return err; + /* go looking in the extended area instead */ + err = xenbus_scanf(XBT_NIL, dev->nodename, "virtual-device-ext", + "%i", &vdevice); + if (err != 1) { + xenbus_dev_fatal(dev, err, "reading virtual-device"); + return err; + } } info = kzalloc(sizeof(*info), GFP_KERNEL); @@ -861,9 +897,7 @@ static void blkfront_connect(struct blkfront_info *info) if (err) info->feature_barrier = 0; - err = xlvbd_alloc_gendisk(BLKIF_MINOR(info->vdevice), - sectors, info->vdevice, - binfo, sector_size, info); + err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size); if (err) { xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s", info->xbdev->otherend); |