diff options
Diffstat (limited to 'pc-bios/s390-ccw/virtio-scsi.c')
| -rw-r--r-- | pc-bios/s390-ccw/virtio-scsi.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/pc-bios/s390-ccw/virtio-scsi.c b/pc-bios/s390-ccw/virtio-scsi.c new file mode 100644 index 0000000000..3bb48e917e --- /dev/null +++ b/pc-bios/s390-ccw/virtio-scsi.c @@ -0,0 +1,342 @@ +/* + * Virtio-SCSI implementation for s390 machine loader for qemu + * + * Copyright 2015 IBM Corp. + * Author: Eugene "jno" Dvurechenski <jno@linux.vnet.ibm.com> + * + * 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 "s390-ccw.h" +#include "virtio.h" +#include "scsi.h" +#include "virtio-scsi.h" + +static ScsiDevice default_scsi_device; +static VirtioScsiCmdReq req; +static VirtioScsiCmdResp resp; + +static uint8_t scsi_inquiry_std_response[256]; + +static inline void vs_assert(bool term, const char **msgs) +{ + if (!term) { + int i = 0; + + sclp_print("\n! "); + while (msgs[i]) { + sclp_print(msgs[i++]); + } + panic(" !\n"); + } +} + +static void virtio_scsi_verify_response(VirtioScsiCmdResp *resp, + const char *title) +{ + const char *mr[] = { + title, ": response ", virtio_scsi_response_msg(resp), 0 + }; + const char *ms[] = { + title, + CDB_STATUS_VALID(resp->status) ? ": " : ": invalid ", + scsi_cdb_status_msg(resp->status), + resp->status == CDB_STATUS_CHECK_CONDITION ? " " : 0, + resp->sense_len ? scsi_cdb_asc_msg(resp->sense) + : "no sense data", + scsi_sense_response(resp->sense) == 0x70 ? ", sure" : "?", + 0 + }; + + vs_assert(resp->response == VIRTIO_SCSI_S_OK, mr); + vs_assert(resp->status == CDB_STATUS_GOOD, ms); +} + +static void prepare_request(VDev *vdev, const void *cdb, int cdb_size, + void *data, uint32_t data_size) +{ + const ScsiDevice *sdev = vdev->scsi_device; + + memset(&req, 0, sizeof(req)); + req.lun = make_lun(sdev->channel, sdev->target, sdev->lun); + memcpy(&req.cdb, cdb, cdb_size); + + memset(&resp, 0, sizeof(resp)); + resp.status = 0xff; /* set invalid */ + resp.response = 0xff; /* */ + + if (data && data_size) { + memset(data, 0, data_size); + } +} + +static inline void vs_io_assert(bool term, const char *msg) +{ + if (!term) { + virtio_scsi_verify_response(&resp, msg); + } +} + +static void vs_run(const char *title, VirtioCmd *cmd, VDev *vdev, + const void *cdb, int cdb_size, + void *data, uint32_t data_size) +{ + prepare_request(vdev, cdb, cdb_size, data, data_size); + vs_io_assert(virtio_run(vdev, VR_REQUEST, cmd) == 0, title); +} + +/* SCSI protocol implementation routines */ + +static bool scsi_inquiry(VDev *vdev, void *data, uint32_t data_size) +{ + ScsiCdbInquiry cdb = { + .command = 0x12, + .alloc_len = data_size < 65535 ? data_size : 65535, + }; + VirtioCmd inquiry[] = { + { &req, sizeof(req), VRING_DESC_F_NEXT }, + { &resp, sizeof(resp), VRING_DESC_F_WRITE | VRING_DESC_F_NEXT }, + { data, data_size, VRING_DESC_F_WRITE }, + }; + + vs_run("inquiry", inquiry, vdev, &cdb, sizeof(cdb), data, data_size); + + return virtio_scsi_response_ok(&resp); +} + +static bool scsi_test_unit_ready(VDev *vdev) +{ + ScsiCdbTestUnitReady cdb = { + .command = 0x00, + }; + VirtioCmd test_unit_ready[] = { + { &req, sizeof(req), VRING_DESC_F_NEXT }, + { &resp, sizeof(resp), VRING_DESC_F_WRITE }, + }; + + prepare_request(vdev, &cdb, sizeof(cdb), 0, 0); + virtio_run(vdev, VR_REQUEST, test_unit_ready); /* ignore errors here */ + + return virtio_scsi_response_ok(&resp); +} + +static bool scsi_report_luns(VDev *vdev, void *data, uint32_t data_size) +{ + ScsiCdbReportLuns cdb = { + .command = 0xa0, + .select_report = 0x02, /* REPORT ALL */ + .alloc_len = data_size, + }; + VirtioCmd report_luns[] = { + { &req, sizeof(req), VRING_DESC_F_NEXT }, + { &resp, sizeof(resp), VRING_DESC_F_WRITE | VRING_DESC_F_NEXT }, + { data, data_size, VRING_DESC_F_WRITE }, + }; + + vs_run("report luns", report_luns, + vdev, &cdb, sizeof(cdb), data, data_size); + + return virtio_scsi_response_ok(&resp); +} + +static bool scsi_read_10(VDev *vdev, + ulong sector, int sectors, void *data) +{ + int f = vdev->blk_factor; + unsigned int data_size = sectors * virtio_get_block_size() * f; + ScsiCdbRead10 cdb = { + .command = 0x28, + .lba = sector * f, + .xfer_length = sectors * f, + }; + VirtioCmd read_10[] = { + { &req, sizeof(req), VRING_DESC_F_NEXT }, + { &resp, sizeof(resp), VRING_DESC_F_WRITE | VRING_DESC_F_NEXT }, + { data, data_size * f, VRING_DESC_F_WRITE }, + }; + + debug_print_int("read_10 sector", sector); + debug_print_int("read_10 sectors", sectors); + + vs_run("read(10)", read_10, vdev, &cdb, sizeof(cdb), data, data_size); + + return virtio_scsi_response_ok(&resp); +} + +static bool scsi_read_capacity(VDev *vdev, + void *data, uint32_t data_size) +{ + ScsiCdbReadCapacity16 cdb = { + .command = 0x9e, /* SERVICE_ACTION_IN_16 */ + .service_action = 0x10, /* SA_READ_CAPACITY */ + .alloc_len = data_size, + }; + VirtioCmd read_capacity_16[] = { + { &req, sizeof(req), VRING_DESC_F_NEXT }, + { &resp, sizeof(resp), VRING_DESC_F_WRITE | VRING_DESC_F_NEXT }, + { data, data_size, VRING_DESC_F_WRITE }, + }; + + vs_run("read capacity", read_capacity_16, + vdev, &cdb, sizeof(cdb), data, data_size); + + return virtio_scsi_response_ok(&resp); +} + +/* virtio-scsi routines */ + +static void virtio_scsi_locate_device(VDev *vdev) +{ + const uint16_t channel = 0; /* again, it's what QEMU does */ + uint16_t target; + static uint8_t data[16 + 8 * 63]; + ScsiLunReport *r = (void *) data; + ScsiDevice *sdev = vdev->scsi_device; + int i, luns; + + /* QEMU has hardcoded channel #0 in many places. + * If this hardcoded value is ever changed, we'll need to add code for + * vdev->config.scsi.max_channel != 0 here. + */ + debug_print_int("config.scsi.max_channel", vdev->config.scsi.max_channel); + debug_print_int("config.scsi.max_target ", vdev->config.scsi.max_target); + debug_print_int("config.scsi.max_lun ", vdev->config.scsi.max_lun); + + for (target = 0; target <= vdev->config.scsi.max_target; target++) { + sdev->channel = channel; + sdev->target = target; /* sdev->lun will be 0 here */ + if (!scsi_report_luns(vdev, data, sizeof(data))) { + if (resp.response == VIRTIO_SCSI_S_BAD_TARGET) { + continue; + } + print_int("target", target); + virtio_scsi_verify_response(&resp, "SCSI cannot report LUNs"); + } + if (r->lun_list_len == 0) { + print_int("no LUNs for target", target); + continue; + } + luns = r->lun_list_len / 8; + debug_print_int("LUNs reported", luns); + if (luns == 1) { + /* There is no ",lun=#" arg for -device or ",lun=0" given. + * Hence, the only LUN reported. + * Usually, it's 0. + */ + sdev->lun = r->lun[0].v16[0]; /* it's returned this way */ + debug_print_int("Have to use LUN", sdev->lun); + return; /* we have to use this device */ + } + for (i = 0; i < luns; i++) { + if (r->lun[i].v64) { + /* Look for non-zero LUN - we have where to choose from */ + sdev->lun = r->lun[i].v16[0]; + debug_print_int("Will use LUN", sdev->lun); + return; /* we have found a device */ + } + } + } + panic("\n! Cannot locate virtio-scsi device !\n"); +} + +int virtio_scsi_read_many(VDev *vdev, + ulong sector, void *load_addr, int sec_num) +{ + if (!scsi_read_10(vdev, sector, sec_num, load_addr)) { + virtio_scsi_verify_response(&resp, "virtio-scsi:read_many"); + } + + return 0; +} + +static bool virtio_scsi_inquiry_response_is_cdrom(void *data) +{ + const ScsiInquiryStd *response = data; + const int resp_data_fmt = response->b3 & 0x0f; + int i; + + IPL_check(resp_data_fmt == 2, "Wrong INQUIRY response format"); + if (resp_data_fmt != 2) { + return false; /* cannot decode */ + } + + if ((response->peripheral_qdt & 0x1f) == SCSI_INQ_RDT_CDROM) { + return true; + } + + for (i = 0; i < sizeof(response->prod_id); i++) { + if (response->prod_id[i] != QEMU_CDROM_SIGNATURE[i]) { + return false; + } + } + return true; +} + +static void scsi_parse_capacity_report(void *data, + uint64_t *last_lba, uint32_t *lb_len) +{ + ScsiReadCapacity16Data *p = data; + + if (last_lba) { + *last_lba = p->ret_lba; + } + + if (lb_len) { + *lb_len = p->lb_len; + } +} + +void virtio_scsi_setup(VDev *vdev) +{ + int retry_test_unit_ready = 3; + uint8_t data[256]; + uint32_t data_size = sizeof(data); + + vdev->scsi_device = &default_scsi_device; + virtio_scsi_locate_device(vdev); + + /* We have to "ping" the device before it becomes readable */ + while (!scsi_test_unit_ready(vdev)) { + + if (!virtio_scsi_response_ok(&resp)) { + uint8_t code = resp.sense[0] & SCSI_SENSE_CODE_MASK; + uint8_t sense_key = resp.sense[2] & SCSI_SENSE_KEY_MASK; + + IPL_assert(resp.sense_len != 0, "virtio-scsi:setup: no SENSE data"); + + IPL_assert(retry_test_unit_ready && code == 0x70 && + sense_key == SCSI_SENSE_KEY_UNIT_ATTENTION, + "virtio-scsi:setup: cannot retry"); + + /* retry on CHECK_CONDITION/UNIT_ATTENTION as it + * may not designate a real error, but it may be + * a result of device reset, etc. + */ + retry_test_unit_ready--; + sleep(1); + continue; + } + + virtio_scsi_verify_response(&resp, "virtio-scsi:setup"); + } + + /* read and cache SCSI INQUIRY response */ + if (!scsi_inquiry(vdev, scsi_inquiry_std_response, + sizeof(scsi_inquiry_std_response))) { + virtio_scsi_verify_response(&resp, "virtio-scsi:setup:inquiry"); + } + + if (virtio_scsi_inquiry_response_is_cdrom(scsi_inquiry_std_response)) { + sclp_print("SCSI CD-ROM detected.\n"); + vdev->is_cdrom = true; + vdev->scsi_block_size = VIRTIO_ISO_BLOCK_SIZE; + } + + if (!scsi_read_capacity(vdev, data, data_size)) { + virtio_scsi_verify_response(&resp, "virtio-scsi:setup:read_capacity"); + } + scsi_parse_capacity_report(data, &vdev->scsi_last_block, + (uint32_t *) &vdev->scsi_block_size); +} |