linux内核md源代码解读 六 先容raid10阵列的运行

raid10的run函数与raid5的run函数最大区别在于setup_conf，那就直接深入核心：

3540 static struct r10conf *setup_conf(struct mddev *mddev)  
3541 {  
3542         struct r10conf *conf = NULL;  
3543         int err = -EINVAL;  
3544         struct geom geo;  
3545         int copies;  
3546   
3547         copies = setup_geo(&geo, mddev, geo_new);  
3548   
3549         if (copies == -2) {  
3550                 printk(KERN_ERR "md/raid10:%s: chunk size must be "
3551                        "at least PAGE_SIZE(%ld) and be a power of 2.n",  
3552                        mdname(mddev), PAGE_SIZE);  
3553                 goto out;  
3554         }  
3555   
3556         if (copies < 2 || copies > mddev->raid_disks) {  
3557                 printk(KERN_ERR "md/raid10:%s: unsupported raid10 layout: 0x%8xn",  
3558                        mdname(mddev), mddev->new_layout);  
3559                 goto out;  
3560         }  
3561   
3562         err = -ENOMEM;  
3563         conf = kzalloc(sizeof(struct r10conf), GFP_KERNEL);  
3564         if (!conf)  
3565                 goto out;  
3566   
3567         /* FIXME calc properly */
3568         conf->mirrors = kzalloc(sizeof(struct raid10_info)*(mddev->raid_disks +  
3569                                                             max(0,-mddev->delta_disks)),  
3570                                 GFP_KERNEL);  
3571         if (!conf->mirrors)  
3572                 goto out;  
3573   
3574         conf->tmppage = alloc_page(GFP_KERNEL);  
3575         if (!conf->tmppage)  
3576                 goto out;  
3577   
3578         conf->geo = geo;  
3579         conf->copies = copies;  
3580         conf->r10bio_pool = mempool_create(NR_RAID10_BIOS, r10bio_pool_alloc,  
3581                                            r10bio_pool_free, conf);  
3582         if (!conf->r10bio_pool)  
3583                 goto out;  
3584   
3585         calc_sectors(conf, mddev->dev_sectors);  
3586         if (mddev->reshape_position == MaxSector) {  
3587                 conf->prev = conf->geo;  
3588                 conf->reshape_progress = MaxSector;  
3589         } else {  
3590                 if (setup_geo(&conf->prev, mddev, geo_old) != conf->copies) {  
3591                         err = -EINVAL;  
3592                         goto out;  
3593                 }  
3594                 conf->reshape_progress = mddev->reshape_position;  
3595                 if (conf->prev.far_offset)  
3596                         conf->prev.stride = 1 << conf->prev.chunk_shift;  
3597                 else
3598                         /* far_copies must be 1 */
3599                         conf->prev.stride = conf->dev_sectors;  
3600         }  
3601         spin_lock_init(&conf->device_lock);  
3602         INIT_LIST_HEAD(&conf->retry_list);  
3603   
3604         spin_lock_init(&conf->resync_lock);  
3605         init_waitqueue_head(&conf->wait_barrier);  
3606   
3607         conf->thread = md_register_thread(raid10d, mddev, "raid10");  
3608         if (!conf->thread)  
3609                 goto out;  
3610   
3611         conf->mddev = mddev;  
3612         return conf;

（编辑：常州站长网）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!