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 static int virtio_blk_read_many(VDev *vdev, ulong sector, void *load_addr, 17 int sec_num) 18 { 19 VirtioBlkOuthdr out_hdr; 20 u8 status; 21 VRing *vr = &vdev->vrings[vdev->cmd_vr_idx]; 22 23 /* Tell the host we want to read */ 24 out_hdr.type = VIRTIO_BLK_T_IN; 25 out_hdr.ioprio = 99; 26 out_hdr.sector = virtio_sector_adjust(sector); 27 28 vring_send_buf(vr, &out_hdr, sizeof(out_hdr), VRING_DESC_F_NEXT); 29 30 /* This is where we want to receive data */ 31 vring_send_buf(vr, load_addr, virtio_get_block_size() * sec_num, 32 VRING_DESC_F_WRITE | VRING_HIDDEN_IS_CHAIN | 33 VRING_DESC_F_NEXT); 34 35 /* status field */ 36 vring_send_buf(vr, &status, sizeof(u8), 37 VRING_DESC_F_WRITE | VRING_HIDDEN_IS_CHAIN); 38 39 /* Now we can tell the host to read */ 40 vring_wait_reply(); 41 42 if (drain_irqs(vr->schid)) { 43 /* Well, whatever status is supposed to contain... */ 44 status = 1; 45 } 46 return status; 47 } 48 49 int virtio_read_many(ulong sector, void *load_addr, int sec_num) 50 { 51 VDev *vdev = virtio_get_device(); 52 53 switch (vdev->senseid.cu_model) { 54 case VIRTIO_ID_BLOCK: 55 return virtio_blk_read_many(vdev, sector, load_addr, sec_num); 56 case VIRTIO_ID_SCSI: 57 return virtio_scsi_read_many(vdev, sector, load_addr, sec_num); 58 } 59 panic("\n! No readable IPL device !\n"); 60 return -1; 61 } 62 63 unsigned long virtio_load_direct(ulong rec_list1, ulong rec_list2, 64 ulong subchan_id, void *load_addr) 65 { 66 u8 status; 67 int sec = rec_list1; 68 int sec_num = ((rec_list2 >> 32) & 0xffff) + 1; 69 int sec_len = rec_list2 >> 48; 70 ulong addr = (ulong)load_addr; 71 72 if (sec_len != virtio_get_block_size()) { 73 return -1; 74 } 75 76 sclp_print("."); 77 status = virtio_read_many(sec, (void *)addr, sec_num); 78 if (status) { 79 panic("I/O Error"); 80 } 81 addr += sec_num * virtio_get_block_size(); 82 83 return addr; 84 } 85 86 int virtio_read(ulong sector, void *load_addr) 87 { 88 return virtio_read_many(sector, load_addr, 1); 89 } 90 91 /* 92 * Other supported value pairs, if any, would need to be added here. 93 * Note: head count is always 15. 94 */ 95 static inline u8 virtio_eckd_sectors_for_block_size(int size) 96 { 97 switch (size) { 98 case 512: 99 return 49; 100 case 1024: 101 return 33; 102 case 2048: 103 return 21; 104 case 4096: 105 return 12; 106 } 107 return 0; 108 } 109 110 VirtioGDN virtio_guessed_disk_nature(void) 111 { 112 return virtio_get_device()->guessed_disk_nature; 113 } 114 115 void virtio_assume_scsi(void) 116 { 117 VDev *vdev = virtio_get_device(); 118 119 switch (vdev->senseid.cu_model) { 120 case VIRTIO_ID_BLOCK: 121 vdev->guessed_disk_nature = VIRTIO_GDN_SCSI; 122 vdev->config.blk.blk_size = VIRTIO_SCSI_BLOCK_SIZE; 123 vdev->config.blk.physical_block_exp = 0; 124 vdev->blk_factor = 1; 125 break; 126 case VIRTIO_ID_SCSI: 127 vdev->scsi_block_size = VIRTIO_SCSI_BLOCK_SIZE; 128 break; 129 } 130 } 131 132 void virtio_assume_iso9660(void) 133 { 134 VDev *vdev = virtio_get_device(); 135 136 switch (vdev->senseid.cu_model) { 137 case VIRTIO_ID_BLOCK: 138 vdev->guessed_disk_nature = VIRTIO_GDN_SCSI; 139 vdev->config.blk.blk_size = VIRTIO_ISO_BLOCK_SIZE; 140 vdev->config.blk.physical_block_exp = 0; 141 vdev->blk_factor = VIRTIO_ISO_BLOCK_SIZE / VIRTIO_SECTOR_SIZE; 142 break; 143 case VIRTIO_ID_SCSI: 144 vdev->scsi_block_size = VIRTIO_ISO_BLOCK_SIZE; 145 break; 146 } 147 } 148 149 void virtio_assume_eckd(void) 150 { 151 VDev *vdev = virtio_get_device(); 152 153 vdev->guessed_disk_nature = VIRTIO_GDN_DASD; 154 vdev->blk_factor = 1; 155 vdev->config.blk.physical_block_exp = 0; 156 switch (vdev->senseid.cu_model) { 157 case VIRTIO_ID_BLOCK: 158 vdev->config.blk.blk_size = 4096; 159 break; 160 case VIRTIO_ID_SCSI: 161 vdev->config.blk.blk_size = vdev->scsi_block_size; 162 break; 163 } 164 vdev->config.blk.geometry.heads = 15; 165 vdev->config.blk.geometry.sectors = 166 virtio_eckd_sectors_for_block_size(vdev->config.blk.blk_size); 167 } 168 169 bool virtio_disk_is_scsi(void) 170 { 171 VDev *vdev = virtio_get_device(); 172 173 if (vdev->guessed_disk_nature == VIRTIO_GDN_SCSI) { 174 return true; 175 } 176 switch (vdev->senseid.cu_model) { 177 case VIRTIO_ID_BLOCK: 178 return (vdev->config.blk.geometry.heads == 255) 179 && (vdev->config.blk.geometry.sectors == 63) 180 && (virtio_get_block_size() == VIRTIO_SCSI_BLOCK_SIZE); 181 case VIRTIO_ID_SCSI: 182 return true; 183 } 184 return false; 185 } 186 187 bool virtio_disk_is_eckd(void) 188 { 189 VDev *vdev = virtio_get_device(); 190 const int block_size = virtio_get_block_size(); 191 192 if (vdev->guessed_disk_nature == VIRTIO_GDN_DASD) { 193 return true; 194 } 195 switch (vdev->senseid.cu_model) { 196 case VIRTIO_ID_BLOCK: 197 return (vdev->config.blk.geometry.heads == 15) 198 && (vdev->config.blk.geometry.sectors == 199 virtio_eckd_sectors_for_block_size(block_size)); 200 case VIRTIO_ID_SCSI: 201 return false; 202 } 203 return false; 204 } 205 206 bool virtio_ipl_disk_is_valid(void) 207 { 208 return virtio_disk_is_scsi() || virtio_disk_is_eckd(); 209 } 210 211 int virtio_get_block_size(void) 212 { 213 VDev *vdev = virtio_get_device(); 214 215 switch (vdev->senseid.cu_model) { 216 case VIRTIO_ID_BLOCK: 217 return vdev->config.blk.blk_size << vdev->config.blk.physical_block_exp; 218 case VIRTIO_ID_SCSI: 219 return vdev->scsi_block_size; 220 } 221 return 0; 222 } 223 224 uint8_t virtio_get_heads(void) 225 { 226 VDev *vdev = virtio_get_device(); 227 228 switch (vdev->senseid.cu_model) { 229 case VIRTIO_ID_BLOCK: 230 return vdev->config.blk.geometry.heads; 231 case VIRTIO_ID_SCSI: 232 return vdev->guessed_disk_nature == VIRTIO_GDN_DASD 233 ? vdev->config.blk.geometry.heads : 255; 234 } 235 return 0; 236 } 237 238 uint8_t virtio_get_sectors(void) 239 { 240 VDev *vdev = virtio_get_device(); 241 242 switch (vdev->senseid.cu_model) { 243 case VIRTIO_ID_BLOCK: 244 return vdev->config.blk.geometry.sectors; 245 case VIRTIO_ID_SCSI: 246 return vdev->guessed_disk_nature == VIRTIO_GDN_DASD 247 ? vdev->config.blk.geometry.sectors : 63; 248 } 249 return 0; 250 } 251 252 uint64_t virtio_get_blocks(void) 253 { 254 VDev *vdev = virtio_get_device(); 255 const uint64_t factor = virtio_get_block_size() / VIRTIO_SECTOR_SIZE; 256 257 switch (vdev->senseid.cu_model) { 258 case VIRTIO_ID_BLOCK: 259 return vdev->config.blk.capacity / factor; 260 case VIRTIO_ID_SCSI: 261 return vdev->scsi_last_block / factor; 262 } 263 return 0; 264 } 265 266 int virtio_blk_setup_device(SubChannelId schid) 267 { 268 VDev *vdev = virtio_get_device(); 269 int ret = 0; 270 271 vdev->schid = schid; 272 virtio_setup_ccw(vdev); 273 274 switch (vdev->senseid.cu_model) { 275 case VIRTIO_ID_BLOCK: 276 sclp_print("Using virtio-blk.\n"); 277 if (!virtio_ipl_disk_is_valid()) { 278 /* make sure all getters but blocksize return 0 for 279 * invalid IPL disk 280 */ 281 memset(&vdev->config.blk, 0, sizeof(vdev->config.blk)); 282 virtio_assume_scsi(); 283 } 284 break; 285 case VIRTIO_ID_SCSI: 286 IPL_assert(vdev->config.scsi.sense_size == VIRTIO_SCSI_SENSE_SIZE, 287 "Config: sense size mismatch"); 288 IPL_assert(vdev->config.scsi.cdb_size == VIRTIO_SCSI_CDB_SIZE, 289 "Config: CDB size mismatch"); 290 291 sclp_print("Using virtio-scsi.\n"); 292 ret = virtio_scsi_setup(vdev); 293 break; 294 default: 295 panic("\n! No IPL device available !\n"); 296 } 297 298 return ret; 299 } 300