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-rw-r--r--pc-bios/s390-ccw/virtio-blkdev.c296
1 files changed, 296 insertions, 0 deletions
diff --git a/pc-bios/s390-ccw/virtio-blkdev.c b/pc-bios/s390-ccw/virtio-blkdev.c
new file mode 100644
index 0000000000..11c56261ca
--- /dev/null
+++ b/pc-bios/s390-ccw/virtio-blkdev.c
@@ -0,0 +1,296 @@
+/*
+ * Virtio driver bits
+ *
+ * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#include "libc.h"
+#include "s390-ccw.h"
+#include "virtio.h"
+#include "virtio-scsi.h"
+
+static int virtio_blk_read_many(VDev *vdev, ulong sector, void *load_addr,
+                                int sec_num)
+{
+    VirtioBlkOuthdr out_hdr;
+    u8 status;
+    VRing *vr = &vdev->vrings[vdev->cmd_vr_idx];
+
+    /* Tell the host we want to read */
+    out_hdr.type = VIRTIO_BLK_T_IN;
+    out_hdr.ioprio = 99;
+    out_hdr.sector = virtio_sector_adjust(sector);
+
+    vring_send_buf(vr, &out_hdr, sizeof(out_hdr), VRING_DESC_F_NEXT);
+
+    /* This is where we want to receive data */
+    vring_send_buf(vr, load_addr, virtio_get_block_size() * sec_num,
+                   VRING_DESC_F_WRITE | VRING_HIDDEN_IS_CHAIN |
+                   VRING_DESC_F_NEXT);
+
+    /* status field */
+    vring_send_buf(vr, &status, sizeof(u8),
+                   VRING_DESC_F_WRITE | VRING_HIDDEN_IS_CHAIN);
+
+    /* Now we can tell the host to read */
+    vring_wait_reply();
+
+    if (drain_irqs(vr->schid)) {
+        /* Well, whatever status is supposed to contain... */
+        status = 1;
+    }
+    return status;
+}
+
+int virtio_read_many(ulong sector, void *load_addr, int sec_num)
+{
+    VDev *vdev = virtio_get_device();
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return virtio_blk_read_many(vdev, sector, load_addr, sec_num);
+    case VIRTIO_ID_SCSI:
+        return virtio_scsi_read_many(vdev, sector, load_addr, sec_num);
+    }
+    panic("\n! No readable IPL device !\n");
+    return -1;
+}
+
+unsigned long virtio_load_direct(ulong rec_list1, ulong rec_list2,
+                                 ulong subchan_id, void *load_addr)
+{
+    u8 status;
+    int sec = rec_list1;
+    int sec_num = ((rec_list2 >> 32) & 0xffff) + 1;
+    int sec_len = rec_list2 >> 48;
+    ulong addr = (ulong)load_addr;
+
+    if (sec_len != virtio_get_block_size()) {
+        return -1;
+    }
+
+    sclp_print(".");
+    status = virtio_read_many(sec, (void *)addr, sec_num);
+    if (status) {
+        panic("I/O Error");
+    }
+    addr += sec_num * virtio_get_block_size();
+
+    return addr;
+}
+
+int virtio_read(ulong sector, void *load_addr)
+{
+    return virtio_read_many(sector, load_addr, 1);
+}
+
+/*
+ * Other supported value pairs, if any, would need to be added here.
+ * Note: head count is always 15.
+ */
+static inline u8 virtio_eckd_sectors_for_block_size(int size)
+{
+    switch (size) {
+    case 512:
+        return 49;
+    case 1024:
+        return 33;
+    case 2048:
+        return 21;
+    case 4096:
+        return 12;
+    }
+    return 0;
+}
+
+VirtioGDN virtio_guessed_disk_nature(void)
+{
+    return virtio_get_device()->guessed_disk_nature;
+}
+
+void virtio_assume_scsi(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        vdev->guessed_disk_nature = VIRTIO_GDN_SCSI;
+        vdev->config.blk.blk_size = VIRTIO_SCSI_BLOCK_SIZE;
+        vdev->config.blk.physical_block_exp = 0;
+        vdev->blk_factor = 1;
+        break;
+    case VIRTIO_ID_SCSI:
+        vdev->scsi_block_size = VIRTIO_SCSI_BLOCK_SIZE;
+        break;
+    }
+}
+
+void virtio_assume_iso9660(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        vdev->guessed_disk_nature = VIRTIO_GDN_SCSI;
+        vdev->config.blk.blk_size = VIRTIO_ISO_BLOCK_SIZE;
+        vdev->config.blk.physical_block_exp = 0;
+        vdev->blk_factor = VIRTIO_ISO_BLOCK_SIZE / VIRTIO_SECTOR_SIZE;
+        break;
+    case VIRTIO_ID_SCSI:
+        vdev->scsi_block_size = VIRTIO_ISO_BLOCK_SIZE;
+        break;
+    }
+}
+
+void virtio_assume_eckd(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    vdev->guessed_disk_nature = VIRTIO_GDN_DASD;
+    vdev->blk_factor = 1;
+    vdev->config.blk.physical_block_exp = 0;
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        vdev->config.blk.blk_size = 4096;
+        break;
+    case VIRTIO_ID_SCSI:
+        vdev->config.blk.blk_size = vdev->scsi_block_size;
+        break;
+    }
+    vdev->config.blk.geometry.heads = 15;
+    vdev->config.blk.geometry.sectors =
+        virtio_eckd_sectors_for_block_size(vdev->config.blk.blk_size);
+}
+
+bool virtio_disk_is_scsi(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    if (vdev->guessed_disk_nature == VIRTIO_GDN_SCSI) {
+        return true;
+    }
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return (vdev->config.blk.geometry.heads == 255)
+            && (vdev->config.blk.geometry.sectors == 63)
+            && (virtio_get_block_size()  == VIRTIO_SCSI_BLOCK_SIZE);
+    case VIRTIO_ID_SCSI:
+        return true;
+    }
+    return false;
+}
+
+bool virtio_disk_is_eckd(void)
+{
+    VDev *vdev = virtio_get_device();
+    const int block_size = virtio_get_block_size();
+
+    if (vdev->guessed_disk_nature == VIRTIO_GDN_DASD) {
+        return true;
+    }
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return (vdev->config.blk.geometry.heads == 15)
+            && (vdev->config.blk.geometry.sectors ==
+                virtio_eckd_sectors_for_block_size(block_size));
+    case VIRTIO_ID_SCSI:
+        return false;
+    }
+    return false;
+}
+
+bool virtio_ipl_disk_is_valid(void)
+{
+    return virtio_disk_is_scsi() || virtio_disk_is_eckd();
+}
+
+int virtio_get_block_size(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return vdev->config.blk.blk_size << vdev->config.blk.physical_block_exp;
+    case VIRTIO_ID_SCSI:
+        return vdev->scsi_block_size;
+    }
+    return 0;
+}
+
+uint8_t virtio_get_heads(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return vdev->config.blk.geometry.heads;
+    case VIRTIO_ID_SCSI:
+        return vdev->guessed_disk_nature == VIRTIO_GDN_DASD
+               ? vdev->config.blk.geometry.heads : 255;
+    }
+    return 0;
+}
+
+uint8_t virtio_get_sectors(void)
+{
+    VDev *vdev = virtio_get_device();
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return vdev->config.blk.geometry.sectors;
+    case VIRTIO_ID_SCSI:
+        return vdev->guessed_disk_nature == VIRTIO_GDN_DASD
+               ? vdev->config.blk.geometry.sectors : 63;
+    }
+    return 0;
+}
+
+uint64_t virtio_get_blocks(void)
+{
+    VDev *vdev = virtio_get_device();
+    const uint64_t factor = virtio_get_block_size() / VIRTIO_SECTOR_SIZE;
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        return vdev->config.blk.capacity / factor;
+    case VIRTIO_ID_SCSI:
+        return vdev->scsi_last_block / factor;
+    }
+    return 0;
+}
+
+void virtio_blk_setup_device(SubChannelId schid)
+{
+    VDev *vdev = virtio_get_device();
+
+    vdev->schid = schid;
+    virtio_setup_ccw(vdev);
+
+    switch (vdev->senseid.cu_model) {
+    case VIRTIO_ID_BLOCK:
+        sclp_print("Using virtio-blk.\n");
+        if (!virtio_ipl_disk_is_valid()) {
+            /* make sure all getters but blocksize return 0 for
+             * invalid IPL disk
+             */
+            memset(&vdev->config.blk, 0, sizeof(vdev->config.blk));
+            virtio_assume_scsi();
+        }
+        break;
+    case VIRTIO_ID_SCSI:
+        IPL_assert(vdev->config.scsi.sense_size == VIRTIO_SCSI_SENSE_SIZE,
+            "Config: sense size mismatch");
+        IPL_assert(vdev->config.scsi.cdb_size == VIRTIO_SCSI_CDB_SIZE,
+            "Config: CDB size mismatch");
+
+        sclp_print("Using virtio-scsi.\n");
+        virtio_scsi_setup(vdev);
+        break;
+    default:
+        panic("\n! No IPL device available !\n");
+    }
+}