pc-bios/s390-ccw/virtio-blkdev.c

   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 void virtio_blk_setup_device(SubChannelId schid)
 267 {
 268     VDev *vdev = virtio_get_device();
 269
 270     vdev->schid = schid;
 271     virtio_setup_ccw(vdev);
 272
 273     switch (vdev->senseid.cu_model) {
 274     case VIRTIO_ID_BLOCK:
 275         sclp_print("Using virtio-blk.\n");
 276         if (!virtio_ipl_disk_is_valid()) {
 277             /* make sure all getters but blocksize return 0 for
 278              * invalid IPL disk
 279              */
 280             memset(&vdev->config.blk, 0, sizeof(vdev->config.blk));
 281             virtio_assume_scsi();
 282         }
 283         break;
 284     case VIRTIO_ID_SCSI:
 285         IPL_assert(vdev->config.scsi.sense_size == VIRTIO_SCSI_SENSE_SIZE,
 286             "Config: sense size mismatch");
 287         IPL_assert(vdev->config.scsi.cdb_size == VIRTIO_SCSI_CDB_SIZE,
 288             "Config: CDB size mismatch");
 289
 290         sclp_print("Using virtio-scsi.\n");
 291         virtio_scsi_setup(vdev);
 292         break;
 293     default:
 294         panic("\n! No IPL device available !\n");
 295     }
 296 }