diff options
Diffstat (limited to 'drivers/scsi/ufs/ufs_bsg.c')
| -rw-r--r-- | drivers/scsi/ufs/ufs_bsg.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/scsi/ufs/ufs_bsg.c b/drivers/scsi/ufs/ufs_bsg.c new file mode 100644 index 000000000000..e5f8e54bf644 --- /dev/null +++ b/drivers/scsi/ufs/ufs_bsg.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * bsg endpoint that supports UPIUs + * + * Copyright (C) 2018 Western Digital Corporation + */ +#include "ufs_bsg.h" + +static int ufs_bsg_get_query_desc_size(struct ufs_hba *hba, int *desc_len, + struct utp_upiu_query *qr) +{ + int desc_size = be16_to_cpu(qr->length); + int desc_id = qr->idn; + int ret; + + if (desc_size <= 0) + return -EINVAL; + + ret = ufshcd_map_desc_id_to_length(hba, desc_id, desc_len); + if (ret || !*desc_len) + return -EINVAL; + + *desc_len = min_t(int, *desc_len, desc_size); + + return 0; +} + +static int ufs_bsg_verify_query_size(struct ufs_hba *hba, + unsigned int request_len, + unsigned int reply_len, + int desc_len, enum query_opcode desc_op) +{ + int min_req_len = sizeof(struct ufs_bsg_request); + int min_rsp_len = sizeof(struct ufs_bsg_reply); + + if (desc_op == UPIU_QUERY_OPCODE_WRITE_DESC) + min_req_len += desc_len; + + if (min_req_len > request_len || min_rsp_len > reply_len) { + dev_err(hba->dev, "not enough space assigned\n"); + return -EINVAL; + } + + return 0; +} + +static int ufs_bsg_verify_query_params(struct ufs_hba *hba, + struct ufs_bsg_request *bsg_request, + unsigned int request_len, + unsigned int reply_len, + uint8_t *desc_buff, int *desc_len, + enum query_opcode desc_op) +{ + struct utp_upiu_query *qr; + + if (desc_op == UPIU_QUERY_OPCODE_READ_DESC) { + dev_err(hba->dev, "unsupported opcode %d\n", desc_op); + return -ENOTSUPP; + } + + if (desc_op != UPIU_QUERY_OPCODE_WRITE_DESC) + goto out; + + qr = &bsg_request->upiu_req.qr; + if (ufs_bsg_get_query_desc_size(hba, desc_len, qr)) { + dev_err(hba->dev, "Illegal desc size\n"); + return -EINVAL; + } + + if (ufs_bsg_verify_query_size(hba, request_len, reply_len, *desc_len, + desc_op)) + return -EINVAL; + + desc_buff = (uint8_t *)(bsg_request + 1); + +out: + return 0; +} + +static int ufs_bsg_request(struct bsg_job *job) +{ + struct ufs_bsg_request *bsg_request = job->request; + struct ufs_bsg_reply *bsg_reply = job->reply; + struct ufs_hba *hba = shost_priv(dev_to_shost(job->dev->parent)); + unsigned int req_len = job->request_len; + unsigned int reply_len = job->reply_len; + struct uic_command uc = {}; + int msgcode; + uint8_t *desc_buff = NULL; + int desc_len = 0; + enum query_opcode desc_op = UPIU_QUERY_OPCODE_NOP; + int ret; + + ret = ufs_bsg_verify_query_size(hba, req_len, reply_len, 0, desc_op); + if (ret) + goto out; + + bsg_reply->reply_payload_rcv_len = 0; + + msgcode = bsg_request->msgcode; + switch (msgcode) { + case UPIU_TRANSACTION_QUERY_REQ: + desc_op = bsg_request->upiu_req.qr.opcode; + ret = ufs_bsg_verify_query_params(hba, bsg_request, req_len, + reply_len, desc_buff, + &desc_len, desc_op); + if (ret) + goto out; + + /* fall through */ + case UPIU_TRANSACTION_NOP_OUT: + case UPIU_TRANSACTION_TASK_REQ: + ret = ufshcd_exec_raw_upiu_cmd(hba, &bsg_request->upiu_req, + &bsg_reply->upiu_rsp, msgcode, + desc_buff, &desc_len, desc_op); + if (ret) + dev_err(hba->dev, + "exe raw upiu: error code %d\n", ret); + + break; + case UPIU_TRANSACTION_UIC_CMD: + memcpy(&uc, &bsg_request->upiu_req.uc, UIC_CMD_SIZE); + ret = ufshcd_send_uic_cmd(hba, &uc); + if (ret) + dev_dbg(hba->dev, + "send uic cmd: error code %d\n", ret); + + memcpy(&bsg_reply->upiu_rsp.uc, &uc, UIC_CMD_SIZE); + + break; + default: + ret = -ENOTSUPP; + dev_err(hba->dev, "unsupported msgcode 0x%x\n", msgcode); + + break; + } + +out: + bsg_reply->result = ret; + job->reply_len = sizeof(struct ufs_bsg_reply) + + bsg_reply->reply_payload_rcv_len; + + bsg_job_done(job, ret, bsg_reply->reply_payload_rcv_len); + + return ret; +} + +/** + * ufs_bsg_remove - detach and remove the added ufs-bsg node + * + * Should be called when unloading the driver. + */ +void ufs_bsg_remove(struct ufs_hba *hba) +{ + struct device *bsg_dev = &hba->bsg_dev; + + if (!hba->bsg_queue) + return; + + bsg_unregister_queue(hba->bsg_queue); + + device_del(bsg_dev); + put_device(bsg_dev); +} + +static inline void ufs_bsg_node_release(struct device *dev) +{ + put_device(dev->parent); +} + +/** + * ufs_bsg_probe - Add ufs bsg device node + * @hba: per adapter object + * + * Called during initial loading of the driver, and before scsi_scan_host. + */ +int ufs_bsg_probe(struct ufs_hba *hba) +{ + struct device *bsg_dev = &hba->bsg_dev; + struct Scsi_Host *shost = hba->host; + struct device *parent = &shost->shost_gendev; + struct request_queue *q; + int ret; + + device_initialize(bsg_dev); + + bsg_dev->parent = get_device(parent); + bsg_dev->release = ufs_bsg_node_release; + + dev_set_name(bsg_dev, "ufs-bsg"); + + ret = device_add(bsg_dev); + if (ret) + goto out; + + q = bsg_setup_queue(bsg_dev, dev_name(bsg_dev), ufs_bsg_request, 0); + if (IS_ERR(q)) { + ret = PTR_ERR(q); + goto out; + } + + hba->bsg_queue = q; + + return 0; + +out: + dev_err(bsg_dev, "fail to initialize a bsg dev %d\n", shost->host_no); + put_device(bsg_dev); + return ret; +} |