1 /* 2 * Virtio Block Device common helpers 3 * 4 * Copyright IBM, Corp. 2007 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 */ 12 13 #include "qemu/osdep.h" 14 15 #include "standard-headers/linux/virtio_blk.h" 16 #include "hw/virtio/virtio.h" 17 #include "hw/virtio/virtio-blk-common.h" 18 19 /* Config size before the discard support (hide associated config fields) */ 20 #define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \ 21 max_discard_sectors) 22 23 /* 24 * Starting from the discard feature, we can use this array to properly 25 * set the config size depending on the features enabled. 26 */ 27 static const VirtIOFeature feature_sizes[] = { 28 {.flags = 1ULL << VIRTIO_BLK_F_DISCARD, 29 .end = endof(struct virtio_blk_config, discard_sector_alignment)}, 30 {.flags = 1ULL << VIRTIO_BLK_F_WRITE_ZEROES, 31 .end = endof(struct virtio_blk_config, write_zeroes_may_unmap)}, 32 {} 33 }; 34 35 const VirtIOConfigSizeParams virtio_blk_cfg_size_params = { 36 .min_size = VIRTIO_BLK_CFG_SIZE, 37 .max_size = sizeof(struct virtio_blk_config), 38 .feature_sizes = feature_sizes 39 }; 40