| /* |
| * 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 "libc.h" |
| #include "s390-ccw.h" |
| #include "virtio.h" |
| #include "scsi.h" |
| #include "virtio-scsi.h" |
| #include "s390-time.h" |
| #include "helper.h" |
| |
| static ScsiDevice default_scsi_device; |
| static VirtioScsiCmdReq req; |
| static VirtioScsiCmdResp resp; |
| |
| static uint8_t scsi_inquiry_std_response[256]; |
| static ScsiInquiryEvpdPages scsi_inquiry_evpd_pages_response; |
| static ScsiInquiryEvpdBl scsi_inquiry_evpd_bl_response; |
| |
| 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, uint8_t evpd, uint8_t page, |
| void *data, uint32_t data_size) |
| { |
| ScsiCdbInquiry cdb = { |
| .command = 0x12, |
| .b1 = evpd, |
| .b2 = page, |
| .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, |
| unsigned int data_size) |
| { |
| ScsiCdbRead10 cdb = { |
| .command = 0x28, |
| .lba = sector, |
| .xfer_length = sectors, |
| }; |
| VirtioCmd read_10[] = { |
| { &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 }, |
| }; |
| |
| 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 */ |
| |
| /* |
| * Tries to locate a SCSI device and and adds the information for the found |
| * device to the vdev->scsi_device structure. |
| * Returns 0 if SCSI device could be located, or a error code < 0 otherwise |
| */ |
| static int 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); |
| debug_print_int("config.scsi.max_sectors", vdev->config.scsi.max_sectors); |
| |
| if (vdev->scsi_device_selected) { |
| sdev->channel = vdev->selected_scsi_device.channel; |
| sdev->target = vdev->selected_scsi_device.target; |
| sdev->lun = vdev->selected_scsi_device.lun; |
| |
| IPL_check(sdev->channel == 0, "non-zero channel requested"); |
| IPL_check(sdev->target <= vdev->config.scsi.max_target, "target# high"); |
| IPL_check(sdev->lun <= vdev->config.scsi.max_lun, "LUN# high"); |
| return 0; |
| } |
| |
| for (target = 0; target <= vdev->config.scsi.max_target; target++) { |
| sdev->channel = channel; |
| sdev->target = target; |
| sdev->lun = 0; /* LUN has to be 0 for REPORT LUNS */ |
| 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 0; /* 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 0; /* we have found a device */ |
| } |
| } |
| } |
| |
| sclp_print("Warning: Could not locate a usable virtio-scsi device\n"); |
| return -ENODEV; |
| } |
| |
| int virtio_scsi_read_many(VDev *vdev, |
| ulong sector, void *load_addr, int sec_num) |
| { |
| int sector_count; |
| int f = vdev->blk_factor; |
| unsigned int data_size; |
| unsigned int max_transfer = MIN_NON_ZERO(vdev->config.scsi.max_sectors, |
| vdev->max_transfer); |
| |
| do { |
| sector_count = MIN_NON_ZERO(sec_num, max_transfer); |
| data_size = sector_count * virtio_get_block_size() * f; |
| if (!scsi_read_10(vdev, sector * f, sector_count * f, load_addr, |
| data_size)) { |
| virtio_scsi_verify_response(&resp, "virtio-scsi:read_many"); |
| } |
| load_addr += data_size; |
| sector += sector_count; |
| sec_num -= sector_count; |
| } while (sec_num > 0); |
| |
| 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; |
| } |
| } |
| |
| int virtio_scsi_setup(VDev *vdev) |
| { |
| int retry_test_unit_ready = 3; |
| uint8_t data[256]; |
| uint32_t data_size = sizeof(data); |
| ScsiInquiryEvpdPages *evpd = &scsi_inquiry_evpd_pages_response; |
| ScsiInquiryEvpdBl *evpd_bl = &scsi_inquiry_evpd_bl_response; |
| int i, ret; |
| |
| vdev->scsi_device = &default_scsi_device; |
| ret = virtio_scsi_locate_device(vdev); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| /* 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_STANDARD, |
| SCSI_INQUIRY_STANDARD_NONE, |
| 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_inquiry(vdev, |
| SCSI_INQUIRY_EVPD, |
| SCSI_INQUIRY_EVPD_SUPPORTED_PAGES, |
| evpd, |
| sizeof(*evpd))) { |
| virtio_scsi_verify_response(&resp, "virtio-scsi:setup:supported_pages"); |
| } |
| |
| debug_print_int("EVPD length", evpd->page_length); |
| |
| for (i = 0; i <= evpd->page_length; i++) { |
| debug_print_int("supported EVPD page", evpd->byte[i]); |
| |
| if (evpd->byte[i] != SCSI_INQUIRY_EVPD_BLOCK_LIMITS) { |
| continue; |
| } |
| |
| if (!scsi_inquiry(vdev, |
| SCSI_INQUIRY_EVPD, |
| SCSI_INQUIRY_EVPD_BLOCK_LIMITS, |
| evpd_bl, |
| sizeof(*evpd_bl))) { |
| virtio_scsi_verify_response(&resp, "virtio-scsi:setup:blocklimits"); |
| } |
| |
| debug_print_int("max transfer", evpd_bl->max_transfer); |
| vdev->max_transfer = evpd_bl->max_transfer; |
| } |
| |
| /* |
| * The host sg driver will often be unhappy with particularly large |
| * I/Os that exceed the block iovec limits. Let's enforce something |
| * reasonable, despite what the device configuration tells us. |
| */ |
| |
| vdev->max_transfer = MIN_NON_ZERO(VIRTIO_SCSI_MAX_SECTORS, |
| vdev->max_transfer); |
| |
| 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); |
| |
| return 0; |
| } |
