1 /* 2 * Virtio driver bits 3 * 4 * Copyright (c) 2013 Alexander Graf <agraf@suse.de> 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or (at 7 * your option) any later version. See the COPYING file in the top-level 8 * directory. 9 */ 10 11 #include "libc.h" 12 #include "s390-ccw.h" 13 #include "virtio.h" 14 #include "virtio-scsi.h" 15 16 #define VIRTIO_BLK_F_GEOMETRY (1 << 4) 17 #define VIRTIO_BLK_F_BLK_SIZE (1 << 6) 18 19 static int virtio_blk_read_many(VDev *vdev, unsigned long sector, void *load_addr, 20 int sec_num) 21 { 22 VirtioBlkOuthdr out_hdr; 23 u8 status; 24 VRing *vr = &vdev->vrings[vdev->cmd_vr_idx]; 25 26 /* Tell the host we want to read */ 27 out_hdr.type = VIRTIO_BLK_T_IN; 28 out_hdr.ioprio = 99; 29 out_hdr.sector = virtio_sector_adjust(sector); 30 31 vring_send_buf(vr, &out_hdr, sizeof(out_hdr), VRING_DESC_F_NEXT); 32 33 /* This is where we want to receive data */ 34 vring_send_buf(vr, load_addr, virtio_get_block_size() * sec_num, 35 VRING_DESC_F_WRITE | VRING_HIDDEN_IS_CHAIN | 36 VRING_DESC_F_NEXT); 37 38 /* status field */ 39 vring_send_buf(vr, &status, sizeof(u8), 40 VRING_DESC_F_WRITE | VRING_HIDDEN_IS_CHAIN); 41 42 /* Now we can tell the host to read */ 43 vring_wait_reply(); 44 45 if (drain_irqs(vr->schid)) { 46 /* Well, whatever status is supposed to contain... */ 47 status = 1; 48 } 49 return status; 50 } 51 52 int virtio_read_many(unsigned long sector, void *load_addr, int sec_num) 53 { 54 VDev *vdev = virtio_get_device(); 55 56 switch (vdev->senseid.cu_model) { 57 case VIRTIO_ID_BLOCK: 58 return virtio_blk_read_many(vdev, sector, load_addr, sec_num); 59 case VIRTIO_ID_SCSI: 60 return virtio_scsi_read_many(vdev, sector, load_addr, sec_num); 61 } 62 panic("\n! No readable IPL device !\n"); 63 return -1; 64 } 65 66 unsigned long virtio_load_direct(unsigned long rec_list1, unsigned long rec_list2, 67 unsigned long subchan_id, void *load_addr) 68 { 69 u8 status; 70 int sec = rec_list1; 71 int sec_num = ((rec_list2 >> 32) & 0xffff) + 1; 72 int sec_len = rec_list2 >> 48; 73 unsigned long addr = (unsigned long)load_addr; 74 75 if (sec_len != virtio_get_block_size()) { 76 return -1; 77 } 78 79 sclp_print("."); 80 status = virtio_read_many(sec, (void *)addr, sec_num); 81 if (status) { 82 panic("I/O Error"); 83 } 84 addr += sec_num * virtio_get_block_size(); 85 86 return addr; 87 } 88 89 int virtio_read(unsigned long sector, void *load_addr) 90 { 91 return virtio_read_many(sector, load_addr, 1); 92 } 93 94 /* 95 * Other supported value pairs, if any, would need to be added here. 96 * Note: head count is always 15. 97 */ 98 static inline u8 virtio_eckd_sectors_for_block_size(int size) 99 { 100 switch (size) { 101 case 512: 102 return 49; 103 case 1024: 104 return 33; 105 case 2048: 106 return 21; 107 case 4096: 108 return 12; 109 } 110 return 0; 111 } 112 113 VirtioGDN virtio_guessed_disk_nature(void) 114 { 115 return virtio_get_device()->guessed_disk_nature; 116 } 117 118 void virtio_assume_iso9660(void) 119 { 120 VDev *vdev = virtio_get_device(); 121 122 switch (vdev->senseid.cu_model) { 123 case VIRTIO_ID_BLOCK: 124 vdev->guessed_disk_nature = VIRTIO_GDN_SCSI; 125 vdev->config.blk.blk_size = VIRTIO_ISO_BLOCK_SIZE; 126 vdev->config.blk.physical_block_exp = 0; 127 vdev->blk_factor = VIRTIO_ISO_BLOCK_SIZE / VIRTIO_SECTOR_SIZE; 128 break; 129 case VIRTIO_ID_SCSI: 130 vdev->scsi_block_size = VIRTIO_ISO_BLOCK_SIZE; 131 break; 132 } 133 } 134 135 void virtio_assume_eckd(void) 136 { 137 VDev *vdev = virtio_get_device(); 138 139 vdev->guessed_disk_nature = VIRTIO_GDN_DASD; 140 vdev->blk_factor = 1; 141 vdev->config.blk.physical_block_exp = 0; 142 switch (vdev->senseid.cu_model) { 143 case VIRTIO_ID_BLOCK: 144 vdev->config.blk.blk_size = VIRTIO_DASD_DEFAULT_BLOCK_SIZE; 145 break; 146 case VIRTIO_ID_SCSI: 147 vdev->config.blk.blk_size = vdev->scsi_block_size; 148 break; 149 } 150 vdev->config.blk.geometry.heads = 15; 151 vdev->config.blk.geometry.sectors = 152 virtio_eckd_sectors_for_block_size(vdev->config.blk.blk_size); 153 } 154 155 bool virtio_ipl_disk_is_valid(void) 156 { 157 int blksize = virtio_get_block_size(); 158 VDev *vdev = virtio_get_device(); 159 160 if (vdev->guessed_disk_nature == VIRTIO_GDN_SCSI || 161 vdev->guessed_disk_nature == VIRTIO_GDN_DASD) { 162 return true; 163 } 164 165 return (vdev->senseid.cu_model == VIRTIO_ID_BLOCK || 166 vdev->senseid.cu_model == VIRTIO_ID_SCSI) && 167 blksize >= 512 && blksize <= 4096; 168 } 169 170 int virtio_get_block_size(void) 171 { 172 VDev *vdev = virtio_get_device(); 173 174 switch (vdev->senseid.cu_model) { 175 case VIRTIO_ID_BLOCK: 176 return vdev->config.blk.blk_size; 177 case VIRTIO_ID_SCSI: 178 return vdev->scsi_block_size; 179 } 180 return 0; 181 } 182 183 uint8_t virtio_get_heads(void) 184 { 185 VDev *vdev = virtio_get_device(); 186 187 switch (vdev->senseid.cu_model) { 188 case VIRTIO_ID_BLOCK: 189 return vdev->config.blk.geometry.heads; 190 case VIRTIO_ID_SCSI: 191 return vdev->guessed_disk_nature == VIRTIO_GDN_DASD 192 ? vdev->config.blk.geometry.heads : 255; 193 } 194 return 0; 195 } 196 197 uint8_t virtio_get_sectors(void) 198 { 199 VDev *vdev = virtio_get_device(); 200 201 switch (vdev->senseid.cu_model) { 202 case VIRTIO_ID_BLOCK: 203 return vdev->config.blk.geometry.sectors; 204 case VIRTIO_ID_SCSI: 205 return vdev->guessed_disk_nature == VIRTIO_GDN_DASD 206 ? vdev->config.blk.geometry.sectors : 63; 207 } 208 return 0; 209 } 210 211 uint64_t virtio_get_blocks(void) 212 { 213 VDev *vdev = virtio_get_device(); 214 const uint64_t factor = virtio_get_block_size() / VIRTIO_SECTOR_SIZE; 215 216 switch (vdev->senseid.cu_model) { 217 case VIRTIO_ID_BLOCK: 218 return vdev->config.blk.capacity / factor; 219 case VIRTIO_ID_SCSI: 220 return vdev->scsi_last_block / factor; 221 } 222 return 0; 223 } 224 225 int virtio_blk_setup_device(SubChannelId schid) 226 { 227 VDev *vdev = virtio_get_device(); 228 229 vdev->guest_features[0] = VIRTIO_BLK_F_GEOMETRY | VIRTIO_BLK_F_BLK_SIZE; 230 vdev->schid = schid; 231 virtio_setup_ccw(vdev); 232 233 sclp_print("Using virtio-blk.\n"); 234 235 return 0; 236 } 237