static int blk_init(struct XenDevice *xendev) { struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); int index, qflags, have_barriers, info = 0; char *h; /* read xenstore entries */ if (blkdev->params == NULL) { blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params"); h = strchr(blkdev->params, ':'); if (h != NULL) { blkdev->fileproto = blkdev->params; blkdev->filename = h+1; *h = 0; } else { blkdev->fileproto = "<unset>"; blkdev->filename = blkdev->params; } } if (blkdev->mode == NULL) blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode"); if (blkdev->type == NULL) blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type"); if (blkdev->dev == NULL) blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev"); if (blkdev->devtype == NULL) blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type"); /* do we have all we need? */ if (blkdev->params == NULL || blkdev->mode == NULL || blkdev->type == NULL || blkdev->dev == NULL) return -1; /* read-only ? */ if (strcmp(blkdev->mode, "w") == 0) { qflags = BDRV_O_RDWR; } else { qflags = 0; info |= VDISK_READONLY; } /* cdrom ? */ if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) info |= VDISK_CDROM; /* init qemu block driver */ index = (blkdev->xendev.dev - 202 * 256) / 16; blkdev->dinfo = drive_get(IF_XEN, 0, index); if (!blkdev->dinfo) { /* setup via xenbus -> create new block driver instance */ xen_be_printf(&blkdev->xendev, 2, "create new bdrv (xenbus setup)\n"); blkdev->bs = bdrv_new(blkdev->dev); if (blkdev->bs) { if (bdrv_open(blkdev->bs, blkdev->filename, qflags, bdrv_find_whitelisted_format(blkdev->fileproto)) != 0) { bdrv_delete(blkdev->bs); blkdev->bs = NULL; } } if (!blkdev->bs) return -1; } else { /* setup via qemu cmdline -> already setup for us */ xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n"); blkdev->bs = blkdev->dinfo->bdrv; } blkdev->file_blk = BLOCK_SIZE; blkdev->file_size = bdrv_getlength(blkdev->bs); if (blkdev->file_size < 0) { xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n", (int)blkdev->file_size, strerror(-blkdev->file_size), blkdev->bs->drv ? blkdev->bs->drv->format_name : "-"); blkdev->file_size = 0; } have_barriers = blkdev->bs->drv && blkdev->bs->drv->bdrv_flush ? 1 : 0; xen_be_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\"," " size %" PRId64 " (%" PRId64 " MB)\n", blkdev->type, blkdev->fileproto, blkdev->filename, blkdev->file_size, blkdev->file_size >> 20); /* fill info */ xenstore_write_be_int(&blkdev->xendev, "feature-barrier", have_barriers); xenstore_write_be_int(&blkdev->xendev, "info", info); xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk); xenstore_write_be_int(&blkdev->xendev, "sectors", blkdev->file_size / blkdev->file_blk); return 0; }