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 = VIRTIO_DASD_DEFAULT_BLOCK_SIZE; 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_ipl_disk_is_valid(void) 170 { 171 int blksize = virtio_get_block_size(); 172 VDev *vdev = virtio_get_device(); 173 174 if (vdev->guessed_disk_nature == VIRTIO_GDN_SCSI || 175 vdev->guessed_disk_nature == VIRTIO_GDN_DASD) { 176 return true; 177 } 178 179 return (vdev->senseid.cu_model == VIRTIO_ID_BLOCK || 180 vdev->senseid.cu_model == VIRTIO_ID_SCSI) && 181 blksize >= 512 && blksize <= 4096; 182 } 183 184 int virtio_get_block_size(void) 185 { 186 VDev *vdev = virtio_get_device(); 187 188 switch (vdev->senseid.cu_model) { 189 case VIRTIO_ID_BLOCK: 190 return vdev->config.blk.blk_size << vdev->config.blk.physical_block_exp; 191 case VIRTIO_ID_SCSI: 192 return vdev->scsi_block_size; 193 } 194 return 0; 195 } 196 197 uint8_t virtio_get_heads(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.heads; 204 case VIRTIO_ID_SCSI: 205 return vdev->guessed_disk_nature == VIRTIO_GDN_DASD 206 ? vdev->config.blk.geometry.heads : 255; 207 } 208 return 0; 209 } 210 211 uint8_t virtio_get_sectors(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.geometry.sectors; 218 case VIRTIO_ID_SCSI: 219 return vdev->guessed_disk_nature == VIRTIO_GDN_DASD 220 ? vdev->config.blk.geometry.sectors : 63; 221 } 222 return 0; 223 } 224 225 uint64_t virtio_get_blocks(void) 226 { 227 VDev *vdev = virtio_get_device(); 228 const uint64_t factor = virtio_get_block_size() / VIRTIO_SECTOR_SIZE; 229 230 switch (vdev->senseid.cu_model) { 231 case VIRTIO_ID_BLOCK: 232 return vdev->config.blk.capacity / factor; 233 case VIRTIO_ID_SCSI: 234 return vdev->scsi_last_block / factor; 235 } 236 return 0; 237 } 238 239 int virtio_blk_setup_device(SubChannelId schid) 240 { 241 VDev *vdev = virtio_get_device(); 242 int ret = 0; 243 244 vdev->schid = schid; 245 virtio_setup_ccw(vdev); 246 247 switch (vdev->senseid.cu_model) { 248 case VIRTIO_ID_BLOCK: 249 sclp_print("Using virtio-blk.\n"); 250 if (!virtio_ipl_disk_is_valid()) { 251 /* make sure all getters but blocksize return 0 for 252 * invalid IPL disk 253 */ 254 memset(&vdev->config.blk, 0, sizeof(vdev->config.blk)); 255 virtio_assume_scsi(); 256 } 257 break; 258 case VIRTIO_ID_SCSI: 259 IPL_assert(vdev->config.scsi.sense_size == VIRTIO_SCSI_SENSE_SIZE, 260 "Config: sense size mismatch"); 261 IPL_assert(vdev->config.scsi.cdb_size == VIRTIO_SCSI_CDB_SIZE, 262 "Config: CDB size mismatch"); 263 264 sclp_print("Using virtio-scsi.\n"); 265 ret = virtio_scsi_setup(vdev); 266 break; 267 default: 268 panic("\n! No IPL device available !\n"); 269 } 270 271 return ret; 272 } 273