cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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scsi_bsg.c (2623B)

      1// SPDX-License-Identifier: GPL-2.0
      2#include <linux/bsg.h>
      3#include <scsi/scsi.h>
      4#include <scsi/scsi_ioctl.h>
      5#include <scsi/scsi_cmnd.h>
      6#include <scsi/scsi_device.h>
      7#include <scsi/sg.h>
      8#include "scsi_priv.h"
      9
     10#define uptr64(val) ((void __user *)(uintptr_t)(val))
     11
     12static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
     13		fmode_t mode, unsigned int timeout)
     14{
     15	struct scsi_cmnd *scmd;
     16	struct request *rq;
     17	struct bio *bio;
     18	int ret;
     19
     20	if (hdr->protocol != BSG_PROTOCOL_SCSI  ||
     21	    hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_CMD)
     22		return -EINVAL;
     23	if (hdr->dout_xfer_len && hdr->din_xfer_len) {
     24		pr_warn_once("BIDI support in bsg has been removed.\n");
     25		return -EOPNOTSUPP;
     26	}
     27
     28	rq = scsi_alloc_request(q, hdr->dout_xfer_len ?
     29				REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
     30	if (IS_ERR(rq))
     31		return PTR_ERR(rq);
     32	rq->timeout = timeout;
     33
     34	scmd = blk_mq_rq_to_pdu(rq);
     35	scmd->cmd_len = hdr->request_len;
     36	if (scmd->cmd_len > sizeof(scmd->cmnd)) {
     37		ret = -EINVAL;
     38		goto out_put_request;
     39	}
     40
     41	ret = -EFAULT;
     42	if (copy_from_user(scmd->cmnd, uptr64(hdr->request), scmd->cmd_len))
     43		goto out_put_request;
     44	ret = -EPERM;
     45	if (!scsi_cmd_allowed(scmd->cmnd, mode))
     46		goto out_put_request;
     47
     48	ret = 0;
     49	if (hdr->dout_xfer_len) {
     50		ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp),
     51				hdr->dout_xfer_len, GFP_KERNEL);
     52	} else if (hdr->din_xfer_len) {
     53		ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp),
     54				hdr->din_xfer_len, GFP_KERNEL);
     55	}
     56
     57	if (ret)
     58		goto out_put_request;
     59
     60	bio = rq->bio;
     61	blk_execute_rq(rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
     62
     63	/*
     64	 * fill in all the output members
     65	 */
     66	hdr->device_status = scmd->result & 0xff;
     67	hdr->transport_status = host_byte(scmd->result);
     68	hdr->driver_status = 0;
     69	if (scsi_status_is_check_condition(scmd->result))
     70		hdr->driver_status = DRIVER_SENSE;
     71	hdr->info = 0;
     72	if (hdr->device_status || hdr->transport_status || hdr->driver_status)
     73		hdr->info |= SG_INFO_CHECK;
     74	hdr->response_len = 0;
     75
     76	if (scmd->sense_len && hdr->response) {
     77		int len = min_t(unsigned int, hdr->max_response_len,
     78				scmd->sense_len);
     79
     80		if (copy_to_user(uptr64(hdr->response), scmd->sense_buffer,
     81				 len))
     82			ret = -EFAULT;
     83		else
     84			hdr->response_len = len;
     85	}
     86
     87	if (rq_data_dir(rq) == READ)
     88		hdr->din_resid = scmd->resid_len;
     89	else
     90		hdr->dout_resid = scmd->resid_len;
     91
     92	blk_rq_unmap_user(bio);
     93
     94out_put_request:
     95	blk_mq_free_request(rq);
     96	return ret;
     97}
     98
     99struct bsg_device *scsi_bsg_register_queue(struct scsi_device *sdev)
    100{
    101	return bsg_register_queue(sdev->request_queue, &sdev->sdev_gendev,
    102			dev_name(&sdev->sdev_gendev), scsi_bsg_sg_io_fn);
    103}