linux-stable/drivers/s390/cio/device_pgid.c
Halil Pasic 37db8985b2 s390/cio: add basic protected virtualization support
As virtio-ccw devices are channel devices, we need to use the
dma area within the common I/O layer for any communication with
the hypervisor.

Note that we do not need to use that area for control blocks
directly referenced by instructions, e.g. the orb.

It handles neither QDIO in the common code, nor any device type specific
stuff (like channel programs constructed by the DASD driver).

An interesting side effect is that virtio structures are now going to
get allocated in 31 bit addressable storage.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-15 12:25:00 +02:00

726 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* CCW device PGID and path verification I/O handling.
*
* Copyright IBM Corp. 2002, 2009
* Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <asm/ccwdev.h>
#include <asm/cio.h>
#include "cio.h"
#include "cio_debug.h"
#include "device.h"
#include "io_sch.h"
#define PGID_RETRIES 256
#define PGID_TIMEOUT (10 * HZ)
static void verify_start(struct ccw_device *cdev);
/*
* Process path verification data and report result.
*/
static void verify_done(struct ccw_device *cdev, int rc)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_dev_id *id = &cdev->private->dev_id;
int mpath = cdev->private->flags.mpath;
int pgroup = cdev->private->flags.pgroup;
if (rc)
goto out;
/* Ensure consistent multipathing state at device and channel. */
if (sch->config.mp != mpath) {
sch->config.mp = mpath;
rc = cio_commit_config(sch);
}
out:
CIO_MSG_EVENT(2, "vrfy: device 0.%x.%04x: rc=%d pgroup=%d mpath=%d "
"vpm=%02x\n", id->ssid, id->devno, rc, pgroup, mpath,
sch->vpm);
ccw_device_verify_done(cdev, rc);
}
/*
* Create channel program to perform a NOOP.
*/
static void nop_build_cp(struct ccw_device *cdev)
{
struct ccw_request *req = &cdev->private->req;
struct ccw1 *cp = cdev->private->dma_area->iccws;
cp->cmd_code = CCW_CMD_NOOP;
cp->cda = 0;
cp->count = 0;
cp->flags = CCW_FLAG_SLI;
req->cp = cp;
}
/*
* Perform NOOP on a single path.
*/
static void nop_do(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
req->lpm = lpm_adjust(req->lpm, sch->schib.pmcw.pam & sch->opm &
~cdev->private->path_noirq_mask);
if (!req->lpm)
goto out_nopath;
nop_build_cp(cdev);
ccw_request_start(cdev);
return;
out_nopath:
verify_done(cdev, sch->vpm ? 0 : -EACCES);
}
/*
* Adjust NOOP I/O status.
*/
static enum io_status nop_filter(struct ccw_device *cdev, void *data,
struct irb *irb, enum io_status status)
{
/* Only subchannel status might indicate a path error. */
if (status == IO_STATUS_ERROR && irb->scsw.cmd.cstat == 0)
return IO_DONE;
return status;
}
/*
* Process NOOP request result for a single path.
*/
static void nop_callback(struct ccw_device *cdev, void *data, int rc)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
switch (rc) {
case 0:
sch->vpm |= req->lpm;
break;
case -ETIME:
cdev->private->path_noirq_mask |= req->lpm;
break;
case -EACCES:
cdev->private->path_notoper_mask |= req->lpm;
break;
default:
goto err;
}
/* Continue on the next path. */
req->lpm >>= 1;
nop_do(cdev);
return;
err:
verify_done(cdev, rc);
}
/*
* Create channel program to perform SET PGID on a single path.
*/
static void spid_build_cp(struct ccw_device *cdev, u8 fn)
{
struct ccw_request *req = &cdev->private->req;
struct ccw1 *cp = cdev->private->dma_area->iccws;
int i = pathmask_to_pos(req->lpm);
struct pgid *pgid = &cdev->private->dma_area->pgid[i];
pgid->inf.fc = fn;
cp->cmd_code = CCW_CMD_SET_PGID;
cp->cda = (u32) (addr_t) pgid;
cp->count = sizeof(*pgid);
cp->flags = CCW_FLAG_SLI;
req->cp = cp;
}
static void pgid_wipeout_callback(struct ccw_device *cdev, void *data, int rc)
{
if (rc) {
/* We don't know the path groups' state. Abort. */
verify_done(cdev, rc);
return;
}
/*
* Path groups have been reset. Restart path verification but
* leave paths in path_noirq_mask out.
*/
cdev->private->flags.pgid_unknown = 0;
verify_start(cdev);
}
/*
* Reset pathgroups and restart path verification, leave unusable paths out.
*/
static void pgid_wipeout_start(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_dev_id *id = &cdev->private->dev_id;
struct ccw_request *req = &cdev->private->req;
u8 fn;
CIO_MSG_EVENT(2, "wipe: device 0.%x.%04x: pvm=%02x nim=%02x\n",
id->ssid, id->devno, cdev->private->pgid_valid_mask,
cdev->private->path_noirq_mask);
/* Initialize request data. */
memset(req, 0, sizeof(*req));
req->timeout = PGID_TIMEOUT;
req->maxretries = PGID_RETRIES;
req->lpm = sch->schib.pmcw.pam;
req->callback = pgid_wipeout_callback;
fn = SPID_FUNC_DISBAND;
if (cdev->private->flags.mpath)
fn |= SPID_FUNC_MULTI_PATH;
spid_build_cp(cdev, fn);
ccw_request_start(cdev);
}
/*
* Perform establish/resign SET PGID on a single path.
*/
static void spid_do(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
u8 fn;
/* Use next available path that is not already in correct state. */
req->lpm = lpm_adjust(req->lpm, cdev->private->pgid_todo_mask);
if (!req->lpm)
goto out_nopath;
/* Channel program setup. */
if (req->lpm & sch->opm)
fn = SPID_FUNC_ESTABLISH;
else
fn = SPID_FUNC_RESIGN;
if (cdev->private->flags.mpath)
fn |= SPID_FUNC_MULTI_PATH;
spid_build_cp(cdev, fn);
ccw_request_start(cdev);
return;
out_nopath:
if (cdev->private->flags.pgid_unknown) {
/* At least one SPID could be partially done. */
pgid_wipeout_start(cdev);
return;
}
verify_done(cdev, sch->vpm ? 0 : -EACCES);
}
/*
* Process SET PGID request result for a single path.
*/
static void spid_callback(struct ccw_device *cdev, void *data, int rc)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
switch (rc) {
case 0:
sch->vpm |= req->lpm & sch->opm;
break;
case -ETIME:
cdev->private->flags.pgid_unknown = 1;
cdev->private->path_noirq_mask |= req->lpm;
break;
case -EACCES:
cdev->private->path_notoper_mask |= req->lpm;
break;
case -EOPNOTSUPP:
if (cdev->private->flags.mpath) {
/* Try without multipathing. */
cdev->private->flags.mpath = 0;
goto out_restart;
}
/* Try without pathgrouping. */
cdev->private->flags.pgroup = 0;
goto out_restart;
default:
goto err;
}
req->lpm >>= 1;
spid_do(cdev);
return;
out_restart:
verify_start(cdev);
return;
err:
verify_done(cdev, rc);
}
static void spid_start(struct ccw_device *cdev)
{
struct ccw_request *req = &cdev->private->req;
/* Initialize request data. */
memset(req, 0, sizeof(*req));
req->timeout = PGID_TIMEOUT;
req->maxretries = PGID_RETRIES;
req->lpm = 0x80;
req->singlepath = 1;
req->callback = spid_callback;
spid_do(cdev);
}
static int pgid_is_reset(struct pgid *p)
{
char *c;
for (c = (char *)p + 1; c < (char *)(p + 1); c++) {
if (*c != 0)
return 0;
}
return 1;
}
static int pgid_cmp(struct pgid *p1, struct pgid *p2)
{
return memcmp((char *) p1 + 1, (char *) p2 + 1,
sizeof(struct pgid) - 1);
}
/*
* Determine pathgroup state from PGID data.
*/
static void pgid_analyze(struct ccw_device *cdev, struct pgid **p,
int *mismatch, u8 *reserved, u8 *reset)
{
struct pgid *pgid = &cdev->private->dma_area->pgid[0];
struct pgid *first = NULL;
int lpm;
int i;
*mismatch = 0;
*reserved = 0;
*reset = 0;
for (i = 0, lpm = 0x80; i < 8; i++, pgid++, lpm >>= 1) {
if ((cdev->private->pgid_valid_mask & lpm) == 0)
continue;
if (pgid->inf.ps.state2 == SNID_STATE2_RESVD_ELSE)
*reserved |= lpm;
if (pgid_is_reset(pgid)) {
*reset |= lpm;
continue;
}
if (!first) {
first = pgid;
continue;
}
if (pgid_cmp(pgid, first) != 0)
*mismatch = 1;
}
if (!first)
first = &channel_subsystems[0]->global_pgid;
*p = first;
}
static u8 pgid_to_donepm(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct pgid *pgid;
int i;
int lpm;
u8 donepm = 0;
/* Set bits for paths which are already in the target state. */
for (i = 0; i < 8; i++) {
lpm = 0x80 >> i;
if ((cdev->private->pgid_valid_mask & lpm) == 0)
continue;
pgid = &cdev->private->dma_area->pgid[i];
if (sch->opm & lpm) {
if (pgid->inf.ps.state1 != SNID_STATE1_GROUPED)
continue;
} else {
if (pgid->inf.ps.state1 != SNID_STATE1_UNGROUPED)
continue;
}
if (cdev->private->flags.mpath) {
if (pgid->inf.ps.state3 != SNID_STATE3_MULTI_PATH)
continue;
} else {
if (pgid->inf.ps.state3 != SNID_STATE3_SINGLE_PATH)
continue;
}
donepm |= lpm;
}
return donepm;
}
static void pgid_fill(struct ccw_device *cdev, struct pgid *pgid)
{
int i;
for (i = 0; i < 8; i++)
memcpy(&cdev->private->dma_area->pgid[i], pgid,
sizeof(struct pgid));
}
/*
* Process SENSE PGID data and report result.
*/
static void snid_done(struct ccw_device *cdev, int rc)
{
struct ccw_dev_id *id = &cdev->private->dev_id;
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct pgid *pgid;
int mismatch = 0;
u8 reserved = 0;
u8 reset = 0;
u8 donepm;
if (rc)
goto out;
pgid_analyze(cdev, &pgid, &mismatch, &reserved, &reset);
if (reserved == cdev->private->pgid_valid_mask)
rc = -EUSERS;
else if (mismatch)
rc = -EOPNOTSUPP;
else {
donepm = pgid_to_donepm(cdev);
sch->vpm = donepm & sch->opm;
cdev->private->pgid_reset_mask |= reset;
cdev->private->pgid_todo_mask &=
~(donepm | cdev->private->path_noirq_mask);
pgid_fill(cdev, pgid);
}
out:
CIO_MSG_EVENT(2, "snid: device 0.%x.%04x: rc=%d pvm=%02x vpm=%02x "
"todo=%02x mism=%d rsvd=%02x reset=%02x\n", id->ssid,
id->devno, rc, cdev->private->pgid_valid_mask, sch->vpm,
cdev->private->pgid_todo_mask, mismatch, reserved, reset);
switch (rc) {
case 0:
if (cdev->private->flags.pgid_unknown) {
pgid_wipeout_start(cdev);
return;
}
/* Anything left to do? */
if (cdev->private->pgid_todo_mask == 0) {
verify_done(cdev, sch->vpm == 0 ? -EACCES : 0);
return;
}
/* Perform path-grouping. */
spid_start(cdev);
break;
case -EOPNOTSUPP:
/* Path-grouping not supported. */
cdev->private->flags.pgroup = 0;
cdev->private->flags.mpath = 0;
verify_start(cdev);
break;
default:
verify_done(cdev, rc);
}
}
/*
* Create channel program to perform a SENSE PGID on a single path.
*/
static void snid_build_cp(struct ccw_device *cdev)
{
struct ccw_request *req = &cdev->private->req;
struct ccw1 *cp = cdev->private->dma_area->iccws;
int i = pathmask_to_pos(req->lpm);
/* Channel program setup. */
cp->cmd_code = CCW_CMD_SENSE_PGID;
cp->cda = (u32) (addr_t) &cdev->private->dma_area->pgid[i];
cp->count = sizeof(struct pgid);
cp->flags = CCW_FLAG_SLI;
req->cp = cp;
}
/*
* Perform SENSE PGID on a single path.
*/
static void snid_do(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
int ret;
req->lpm = lpm_adjust(req->lpm, sch->schib.pmcw.pam &
~cdev->private->path_noirq_mask);
if (!req->lpm)
goto out_nopath;
snid_build_cp(cdev);
ccw_request_start(cdev);
return;
out_nopath:
if (cdev->private->pgid_valid_mask)
ret = 0;
else if (cdev->private->path_noirq_mask)
ret = -ETIME;
else
ret = -EACCES;
snid_done(cdev, ret);
}
/*
* Process SENSE PGID request result for single path.
*/
static void snid_callback(struct ccw_device *cdev, void *data, int rc)
{
struct ccw_request *req = &cdev->private->req;
switch (rc) {
case 0:
cdev->private->pgid_valid_mask |= req->lpm;
break;
case -ETIME:
cdev->private->flags.pgid_unknown = 1;
cdev->private->path_noirq_mask |= req->lpm;
break;
case -EACCES:
cdev->private->path_notoper_mask |= req->lpm;
break;
default:
goto err;
}
/* Continue on the next path. */
req->lpm >>= 1;
snid_do(cdev);
return;
err:
snid_done(cdev, rc);
}
/*
* Perform path verification.
*/
static void verify_start(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
struct ccw_dev_id *devid = &cdev->private->dev_id;
sch->vpm = 0;
sch->lpm = sch->schib.pmcw.pam;
/* Initialize PGID data. */
memset(cdev->private->dma_area->pgid, 0,
sizeof(cdev->private->dma_area->pgid));
cdev->private->pgid_valid_mask = 0;
cdev->private->pgid_todo_mask = sch->schib.pmcw.pam;
cdev->private->path_notoper_mask = 0;
/* Initialize request data. */
memset(req, 0, sizeof(*req));
req->timeout = PGID_TIMEOUT;
req->maxretries = PGID_RETRIES;
req->lpm = 0x80;
req->singlepath = 1;
if (cdev->private->flags.pgroup) {
CIO_TRACE_EVENT(4, "snid");
CIO_HEX_EVENT(4, devid, sizeof(*devid));
req->callback = snid_callback;
snid_do(cdev);
} else {
CIO_TRACE_EVENT(4, "nop");
CIO_HEX_EVENT(4, devid, sizeof(*devid));
req->filter = nop_filter;
req->callback = nop_callback;
nop_do(cdev);
}
}
/**
* ccw_device_verify_start - perform path verification
* @cdev: ccw device
*
* Perform an I/O on each available channel path to @cdev to determine which
* paths are operational. The resulting path mask is stored in sch->vpm.
* If device options specify pathgrouping, establish a pathgroup for the
* operational paths. When finished, call ccw_device_verify_done with a
* return code specifying the result.
*/
void ccw_device_verify_start(struct ccw_device *cdev)
{
CIO_TRACE_EVENT(4, "vrfy");
CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
/*
* Initialize pathgroup and multipath state with target values.
* They may change in the course of path verification.
*/
cdev->private->flags.pgroup = cdev->private->options.pgroup;
cdev->private->flags.mpath = cdev->private->options.mpath;
cdev->private->flags.doverify = 0;
cdev->private->path_noirq_mask = 0;
verify_start(cdev);
}
/*
* Process disband SET PGID request result.
*/
static void disband_callback(struct ccw_device *cdev, void *data, int rc)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_dev_id *id = &cdev->private->dev_id;
if (rc)
goto out;
/* Ensure consistent multipathing state at device and channel. */
cdev->private->flags.mpath = 0;
if (sch->config.mp) {
sch->config.mp = 0;
rc = cio_commit_config(sch);
}
out:
CIO_MSG_EVENT(0, "disb: device 0.%x.%04x: rc=%d\n", id->ssid, id->devno,
rc);
ccw_device_disband_done(cdev, rc);
}
/**
* ccw_device_disband_start - disband pathgroup
* @cdev: ccw device
*
* Execute a SET PGID channel program on @cdev to disband a previously
* established pathgroup. When finished, call ccw_device_disband_done with
* a return code specifying the result.
*/
void ccw_device_disband_start(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
u8 fn;
CIO_TRACE_EVENT(4, "disb");
CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
/* Request setup. */
memset(req, 0, sizeof(*req));
req->timeout = PGID_TIMEOUT;
req->maxretries = PGID_RETRIES;
req->lpm = sch->schib.pmcw.pam & sch->opm;
req->singlepath = 1;
req->callback = disband_callback;
fn = SPID_FUNC_DISBAND;
if (cdev->private->flags.mpath)
fn |= SPID_FUNC_MULTI_PATH;
spid_build_cp(cdev, fn);
ccw_request_start(cdev);
}
struct stlck_data {
struct completion done;
int rc;
};
static void stlck_build_cp(struct ccw_device *cdev, void *buf1, void *buf2)
{
struct ccw_request *req = &cdev->private->req;
struct ccw1 *cp = cdev->private->dma_area->iccws;
cp[0].cmd_code = CCW_CMD_STLCK;
cp[0].cda = (u32) (addr_t) buf1;
cp[0].count = 32;
cp[0].flags = CCW_FLAG_CC;
cp[1].cmd_code = CCW_CMD_RELEASE;
cp[1].cda = (u32) (addr_t) buf2;
cp[1].count = 32;
cp[1].flags = 0;
req->cp = cp;
}
static void stlck_callback(struct ccw_device *cdev, void *data, int rc)
{
struct stlck_data *sdata = data;
sdata->rc = rc;
complete(&sdata->done);
}
/**
* ccw_device_stlck_start - perform unconditional release
* @cdev: ccw device
* @data: data pointer to be passed to ccw_device_stlck_done
* @buf1: data pointer used in channel program
* @buf2: data pointer used in channel program
*
* Execute a channel program on @cdev to release an existing PGID reservation.
*/
static void ccw_device_stlck_start(struct ccw_device *cdev, void *data,
void *buf1, void *buf2)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
CIO_TRACE_EVENT(4, "stlck");
CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
/* Request setup. */
memset(req, 0, sizeof(*req));
req->timeout = PGID_TIMEOUT;
req->maxretries = PGID_RETRIES;
req->lpm = sch->schib.pmcw.pam & sch->opm;
req->data = data;
req->callback = stlck_callback;
stlck_build_cp(cdev, buf1, buf2);
ccw_request_start(cdev);
}
/*
* Perform unconditional reserve + release.
*/
int ccw_device_stlck(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct stlck_data data;
u8 *buffer;
int rc;
/* Check if steal lock operation is valid for this device. */
if (cdev->drv) {
if (!cdev->private->options.force)
return -EINVAL;
}
buffer = kzalloc(64, GFP_DMA | GFP_KERNEL);
if (!buffer)
return -ENOMEM;
init_completion(&data.done);
data.rc = -EIO;
spin_lock_irq(sch->lock);
rc = cio_enable_subchannel(sch, (u32) (addr_t) sch);
if (rc)
goto out_unlock;
/* Perform operation. */
cdev->private->state = DEV_STATE_STEAL_LOCK;
ccw_device_stlck_start(cdev, &data, &buffer[0], &buffer[32]);
spin_unlock_irq(sch->lock);
/* Wait for operation to finish. */
if (wait_for_completion_interruptible(&data.done)) {
/* Got a signal. */
spin_lock_irq(sch->lock);
ccw_request_cancel(cdev);
spin_unlock_irq(sch->lock);
wait_for_completion(&data.done);
}
rc = data.rc;
/* Check results. */
spin_lock_irq(sch->lock);
cio_disable_subchannel(sch);
cdev->private->state = DEV_STATE_BOXED;
out_unlock:
spin_unlock_irq(sch->lock);
kfree(buffer);
return rc;
}