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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device_id.c (6002B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 *  CCW device SENSE ID I/O handling.
      4 *
      5 *    Copyright IBM Corp. 2002, 2009
      6 *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
      7 *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
      8 *		 Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
      9 */
     10
     11#include <linux/kernel.h>
     12#include <linux/string.h>
     13#include <linux/types.h>
     14#include <linux/errno.h>
     15#include <asm/ccwdev.h>
     16#include <asm/setup.h>
     17#include <asm/cio.h>
     18#include <asm/diag.h>
     19
     20#include "cio.h"
     21#include "cio_debug.h"
     22#include "device.h"
     23#include "io_sch.h"
     24
     25#define SENSE_ID_RETRIES	256
     26#define SENSE_ID_TIMEOUT	(10 * HZ)
     27#define SENSE_ID_MIN_LEN	4
     28#define SENSE_ID_BASIC_LEN	7
     29
     30/**
     31 * diag210_to_senseid - convert diag 0x210 data to sense id information
     32 * @senseid: sense id
     33 * @diag: diag 0x210 data
     34 *
     35 * Return 0 on success, non-zero otherwise.
     36 */
     37static int diag210_to_senseid(struct senseid *senseid, struct diag210 *diag)
     38{
     39	static struct {
     40		int class, type, cu_type;
     41	} vm_devices[] = {
     42		{ 0x08, 0x01, 0x3480 },
     43		{ 0x08, 0x02, 0x3430 },
     44		{ 0x08, 0x10, 0x3420 },
     45		{ 0x08, 0x42, 0x3424 },
     46		{ 0x08, 0x44, 0x9348 },
     47		{ 0x08, 0x81, 0x3490 },
     48		{ 0x08, 0x82, 0x3422 },
     49		{ 0x10, 0x41, 0x1403 },
     50		{ 0x10, 0x42, 0x3211 },
     51		{ 0x10, 0x43, 0x3203 },
     52		{ 0x10, 0x45, 0x3800 },
     53		{ 0x10, 0x47, 0x3262 },
     54		{ 0x10, 0x48, 0x3820 },
     55		{ 0x10, 0x49, 0x3800 },
     56		{ 0x10, 0x4a, 0x4245 },
     57		{ 0x10, 0x4b, 0x4248 },
     58		{ 0x10, 0x4d, 0x3800 },
     59		{ 0x10, 0x4e, 0x3820 },
     60		{ 0x10, 0x4f, 0x3820 },
     61		{ 0x10, 0x82, 0x2540 },
     62		{ 0x10, 0x84, 0x3525 },
     63		{ 0x20, 0x81, 0x2501 },
     64		{ 0x20, 0x82, 0x2540 },
     65		{ 0x20, 0x84, 0x3505 },
     66		{ 0x40, 0x01, 0x3278 },
     67		{ 0x40, 0x04, 0x3277 },
     68		{ 0x40, 0x80, 0x2250 },
     69		{ 0x40, 0xc0, 0x5080 },
     70		{ 0x80, 0x00, 0x3215 },
     71	};
     72	int i;
     73
     74	/* Special case for osa devices. */
     75	if (diag->vrdcvcla == 0x02 && diag->vrdcvtyp == 0x20) {
     76		senseid->cu_type = 0x3088;
     77		senseid->cu_model = 0x60;
     78		senseid->reserved = 0xff;
     79		return 0;
     80	}
     81	for (i = 0; i < ARRAY_SIZE(vm_devices); i++) {
     82		if (diag->vrdcvcla == vm_devices[i].class &&
     83		    diag->vrdcvtyp == vm_devices[i].type) {
     84			senseid->cu_type = vm_devices[i].cu_type;
     85			senseid->reserved = 0xff;
     86			return 0;
     87		}
     88	}
     89
     90	return -ENODEV;
     91}
     92
     93/**
     94 * diag210_get_dev_info - retrieve device information via diag 0x210
     95 * @cdev: ccw device
     96 *
     97 * Returns zero on success, non-zero otherwise.
     98 */
     99static int diag210_get_dev_info(struct ccw_device *cdev)
    100{
    101	struct ccw_dev_id *dev_id = &cdev->private->dev_id;
    102	struct senseid *senseid = &cdev->private->dma_area->senseid;
    103	struct diag210 diag_data;
    104	int rc;
    105
    106	if (dev_id->ssid != 0)
    107		return -ENODEV;
    108	memset(&diag_data, 0, sizeof(diag_data));
    109	diag_data.vrdcdvno	= dev_id->devno;
    110	diag_data.vrdclen	= sizeof(diag_data);
    111	rc = diag210(&diag_data);
    112	CIO_TRACE_EVENT(4, "diag210");
    113	CIO_HEX_EVENT(4, &rc, sizeof(rc));
    114	CIO_HEX_EVENT(4, &diag_data, sizeof(diag_data));
    115	if (rc != 0 && rc != 2)
    116		goto err_failed;
    117	if (diag210_to_senseid(senseid, &diag_data))
    118		goto err_unknown;
    119	return 0;
    120
    121err_unknown:
    122	CIO_MSG_EVENT(0, "snsid: device 0.%x.%04x: unknown diag210 data\n",
    123		      dev_id->ssid, dev_id->devno);
    124	return -ENODEV;
    125err_failed:
    126	CIO_MSG_EVENT(0, "snsid: device 0.%x.%04x: diag210 failed (rc=%d)\n",
    127		      dev_id->ssid, dev_id->devno, rc);
    128	return -ENODEV;
    129}
    130
    131/*
    132 * Initialize SENSE ID data.
    133 */
    134static void snsid_init(struct ccw_device *cdev)
    135{
    136	cdev->private->flags.esid = 0;
    137
    138	memset(&cdev->private->dma_area->senseid, 0,
    139	       sizeof(cdev->private->dma_area->senseid));
    140	cdev->private->dma_area->senseid.cu_type = 0xffff;
    141}
    142
    143/*
    144 * Check for complete SENSE ID data.
    145 */
    146static int snsid_check(struct ccw_device *cdev, void *data)
    147{
    148	struct cmd_scsw *scsw = &cdev->private->dma_area->irb.scsw.cmd;
    149	int len = sizeof(struct senseid) - scsw->count;
    150
    151	/* Check for incomplete SENSE ID data. */
    152	if (len < SENSE_ID_MIN_LEN)
    153		goto out_restart;
    154	if (cdev->private->dma_area->senseid.cu_type == 0xffff)
    155		goto out_restart;
    156	/* Check for incompatible SENSE ID data. */
    157	if (cdev->private->dma_area->senseid.reserved != 0xff)
    158		return -EOPNOTSUPP;
    159	/* Check for extended-identification information. */
    160	if (len > SENSE_ID_BASIC_LEN)
    161		cdev->private->flags.esid = 1;
    162	return 0;
    163
    164out_restart:
    165	snsid_init(cdev);
    166	return -EAGAIN;
    167}
    168
    169/*
    170 * Process SENSE ID request result.
    171 */
    172static void snsid_callback(struct ccw_device *cdev, void *data, int rc)
    173{
    174	struct ccw_dev_id *id = &cdev->private->dev_id;
    175	struct senseid *senseid = &cdev->private->dma_area->senseid;
    176	int vm = 0;
    177
    178	if (rc && MACHINE_IS_VM) {
    179		/* Try diag 0x210 fallback on z/VM. */
    180		snsid_init(cdev);
    181		if (diag210_get_dev_info(cdev) == 0) {
    182			rc = 0;
    183			vm = 1;
    184		}
    185	}
    186	CIO_MSG_EVENT(2, "snsid: device 0.%x.%04x: rc=%d %04x/%02x "
    187		      "%04x/%02x%s\n", id->ssid, id->devno, rc,
    188		      senseid->cu_type, senseid->cu_model, senseid->dev_type,
    189		      senseid->dev_model, vm ? " (diag210)" : "");
    190	ccw_device_sense_id_done(cdev, rc);
    191}
    192
    193/**
    194 * ccw_device_sense_id_start - perform SENSE ID
    195 * @cdev: ccw device
    196 *
    197 * Execute a SENSE ID channel program on @cdev to update its sense id
    198 * information. When finished, call ccw_device_sense_id_done with a
    199 * return code specifying the result.
    200 */
    201void ccw_device_sense_id_start(struct ccw_device *cdev)
    202{
    203	struct subchannel *sch = to_subchannel(cdev->dev.parent);
    204	struct ccw_request *req = &cdev->private->req;
    205	struct ccw1 *cp = cdev->private->dma_area->iccws;
    206
    207	CIO_TRACE_EVENT(4, "snsid");
    208	CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
    209	/* Data setup. */
    210	snsid_init(cdev);
    211	/* Channel program setup. */
    212	cp->cmd_code	= CCW_CMD_SENSE_ID;
    213	cp->cda		= (u32) (addr_t) &cdev->private->dma_area->senseid;
    214	cp->count	= sizeof(struct senseid);
    215	cp->flags	= CCW_FLAG_SLI;
    216	/* Request setup. */
    217	memset(req, 0, sizeof(*req));
    218	req->cp		= cp;
    219	req->timeout	= SENSE_ID_TIMEOUT;
    220	req->maxretries	= SENSE_ID_RETRIES;
    221	req->lpm	= sch->schib.pmcw.pam & sch->opm;
    222	req->check	= snsid_check;
    223	req->callback	= snsid_callback;
    224	ccw_request_start(cdev);
    225}