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1b60741127
The channel-subsystem-driver scans for newly available devices whenever device-IDs are removed from the cio_ignore list using a command such as: echo free >/proc/cio_ignore Since an I/O device scan might interfer with running I/Os, commit172da89ed0
("s390/cio: avoid excessive path-verification requests") introduced an optimization to exclude online devices from the scan. The newly added check for online devices incorrectly assumes that an I/O-subchannel's drvdata points to a struct io_subchannel_private. For devices that are bound to a non-default I/O subchannel driver, such as the vfio_ccw driver, this results in an out-of-bounds read access during each scan. Fix this by changing the scan logic to rely on a driver-independent online indication. For this we can use struct subchannel->config.ena, which is the driver's requested subchannel-enabled state. Since I/Os can only be started on enabled subchannels, this matches the intent of the original optimization of not scanning devices where I/O might be running. Fixes:172da89ed0
("s390/cio: avoid excessive path-verification requests") Fixes:0c3812c347
("s390/cio: derive cdev information only for IO-subchannels") Cc: <stable@vger.kernel.org> # v5.15 Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com> Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
1451 lines
33 KiB
C
1451 lines
33 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* driver for channel subsystem
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*
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* Copyright IBM Corp. 2002, 2010
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*
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* Author(s): Arnd Bergmann (arndb@de.ibm.com)
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* Cornelia Huck (cornelia.huck@de.ibm.com)
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*/
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#define KMSG_COMPONENT "cio"
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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#include <linux/export.h>
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#include <linux/init.h>
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#include <linux/device.h>
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#include <linux/slab.h>
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#include <linux/errno.h>
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#include <linux/list.h>
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#include <linux/reboot.h>
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#include <linux/proc_fs.h>
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#include <linux/genalloc.h>
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#include <linux/dma-mapping.h>
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#include <asm/isc.h>
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#include <asm/crw.h>
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#include "css.h"
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#include "cio.h"
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#include "blacklist.h"
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#include "cio_debug.h"
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#include "ioasm.h"
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#include "chsc.h"
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#include "device.h"
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#include "idset.h"
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#include "chp.h"
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int css_init_done = 0;
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int max_ssid;
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#define MAX_CSS_IDX 0
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struct channel_subsystem *channel_subsystems[MAX_CSS_IDX + 1];
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static struct bus_type css_bus_type;
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int
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for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *data)
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{
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struct subchannel_id schid;
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int ret;
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init_subchannel_id(&schid);
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do {
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do {
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ret = fn(schid, data);
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if (ret)
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break;
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} while (schid.sch_no++ < __MAX_SUBCHANNEL);
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schid.sch_no = 0;
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} while (schid.ssid++ < max_ssid);
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return ret;
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}
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struct cb_data {
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void *data;
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struct idset *set;
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int (*fn_known_sch)(struct subchannel *, void *);
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int (*fn_unknown_sch)(struct subchannel_id, void *);
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};
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static int call_fn_known_sch(struct device *dev, void *data)
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{
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struct subchannel *sch = to_subchannel(dev);
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struct cb_data *cb = data;
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int rc = 0;
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if (cb->set)
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idset_sch_del(cb->set, sch->schid);
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if (cb->fn_known_sch)
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rc = cb->fn_known_sch(sch, cb->data);
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return rc;
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}
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static int call_fn_unknown_sch(struct subchannel_id schid, void *data)
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{
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struct cb_data *cb = data;
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int rc = 0;
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if (idset_sch_contains(cb->set, schid))
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rc = cb->fn_unknown_sch(schid, cb->data);
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return rc;
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}
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static int call_fn_all_sch(struct subchannel_id schid, void *data)
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{
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struct cb_data *cb = data;
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struct subchannel *sch;
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int rc = 0;
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sch = get_subchannel_by_schid(schid);
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if (sch) {
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if (cb->fn_known_sch)
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rc = cb->fn_known_sch(sch, cb->data);
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put_device(&sch->dev);
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} else {
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if (cb->fn_unknown_sch)
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rc = cb->fn_unknown_sch(schid, cb->data);
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}
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return rc;
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}
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int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
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int (*fn_unknown)(struct subchannel_id,
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void *), void *data)
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{
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struct cb_data cb;
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int rc;
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cb.data = data;
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cb.fn_known_sch = fn_known;
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cb.fn_unknown_sch = fn_unknown;
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if (fn_known && !fn_unknown) {
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/* Skip idset allocation in case of known-only loop. */
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cb.set = NULL;
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return bus_for_each_dev(&css_bus_type, NULL, &cb,
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call_fn_known_sch);
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}
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cb.set = idset_sch_new();
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if (!cb.set)
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/* fall back to brute force scanning in case of oom */
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return for_each_subchannel(call_fn_all_sch, &cb);
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idset_fill(cb.set);
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/* Process registered subchannels. */
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rc = bus_for_each_dev(&css_bus_type, NULL, &cb, call_fn_known_sch);
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if (rc)
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goto out;
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/* Process unregistered subchannels. */
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if (fn_unknown)
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rc = for_each_subchannel(call_fn_unknown_sch, &cb);
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out:
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idset_free(cb.set);
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return rc;
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}
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static void css_sch_todo(struct work_struct *work);
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static int css_sch_create_locks(struct subchannel *sch)
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{
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sch->lock = kmalloc(sizeof(*sch->lock), GFP_KERNEL);
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if (!sch->lock)
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return -ENOMEM;
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spin_lock_init(sch->lock);
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mutex_init(&sch->reg_mutex);
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return 0;
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}
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static void css_subchannel_release(struct device *dev)
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{
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struct subchannel *sch = to_subchannel(dev);
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sch->config.intparm = 0;
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cio_commit_config(sch);
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kfree(sch->driver_override);
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kfree(sch->lock);
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kfree(sch);
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}
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static int css_validate_subchannel(struct subchannel_id schid,
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struct schib *schib)
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{
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int err;
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switch (schib->pmcw.st) {
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case SUBCHANNEL_TYPE_IO:
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case SUBCHANNEL_TYPE_MSG:
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if (!css_sch_is_valid(schib))
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err = -ENODEV;
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else if (is_blacklisted(schid.ssid, schib->pmcw.dev)) {
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CIO_MSG_EVENT(6, "Blacklisted device detected "
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"at devno %04X, subchannel set %x\n",
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schib->pmcw.dev, schid.ssid);
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err = -ENODEV;
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} else
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err = 0;
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break;
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default:
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err = 0;
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}
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if (err)
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goto out;
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CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n",
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schid.ssid, schid.sch_no, schib->pmcw.st);
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out:
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return err;
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}
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struct subchannel *css_alloc_subchannel(struct subchannel_id schid,
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struct schib *schib)
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{
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struct subchannel *sch;
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int ret;
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ret = css_validate_subchannel(schid, schib);
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if (ret < 0)
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return ERR_PTR(ret);
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sch = kzalloc(sizeof(*sch), GFP_KERNEL | GFP_DMA);
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if (!sch)
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return ERR_PTR(-ENOMEM);
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sch->schid = schid;
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sch->schib = *schib;
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sch->st = schib->pmcw.st;
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ret = css_sch_create_locks(sch);
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if (ret)
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goto err;
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INIT_WORK(&sch->todo_work, css_sch_todo);
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sch->dev.release = &css_subchannel_release;
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sch->dev.dma_mask = &sch->dma_mask;
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device_initialize(&sch->dev);
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/*
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* The physical addresses for some of the dma structures that can
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* belong to a subchannel need to fit 31 bit width (e.g. ccw).
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*/
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ret = dma_set_coherent_mask(&sch->dev, DMA_BIT_MASK(31));
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if (ret)
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goto err;
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/*
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* But we don't have such restrictions imposed on the stuff that
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* is handled by the streaming API.
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*/
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ret = dma_set_mask(&sch->dev, DMA_BIT_MASK(64));
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if (ret)
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goto err;
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return sch;
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err:
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kfree(sch);
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return ERR_PTR(ret);
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}
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static int css_sch_device_register(struct subchannel *sch)
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{
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int ret;
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mutex_lock(&sch->reg_mutex);
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dev_set_name(&sch->dev, "0.%x.%04x", sch->schid.ssid,
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sch->schid.sch_no);
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ret = device_add(&sch->dev);
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mutex_unlock(&sch->reg_mutex);
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return ret;
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}
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/**
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* css_sch_device_unregister - unregister a subchannel
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* @sch: subchannel to be unregistered
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*/
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void css_sch_device_unregister(struct subchannel *sch)
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{
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mutex_lock(&sch->reg_mutex);
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if (device_is_registered(&sch->dev))
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device_unregister(&sch->dev);
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mutex_unlock(&sch->reg_mutex);
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}
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EXPORT_SYMBOL_GPL(css_sch_device_unregister);
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static void ssd_from_pmcw(struct chsc_ssd_info *ssd, struct pmcw *pmcw)
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{
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int i;
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int mask;
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memset(ssd, 0, sizeof(struct chsc_ssd_info));
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ssd->path_mask = pmcw->pim;
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for (i = 0; i < 8; i++) {
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mask = 0x80 >> i;
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if (pmcw->pim & mask) {
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chp_id_init(&ssd->chpid[i]);
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ssd->chpid[i].id = pmcw->chpid[i];
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}
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}
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}
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static void ssd_register_chpids(struct chsc_ssd_info *ssd)
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{
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int i;
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int mask;
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for (i = 0; i < 8; i++) {
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mask = 0x80 >> i;
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if (ssd->path_mask & mask)
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chp_new(ssd->chpid[i]);
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}
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}
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void css_update_ssd_info(struct subchannel *sch)
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{
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int ret;
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ret = chsc_get_ssd_info(sch->schid, &sch->ssd_info);
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if (ret)
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ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
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ssd_register_chpids(&sch->ssd_info);
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}
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static ssize_t type_show(struct device *dev, struct device_attribute *attr,
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char *buf)
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{
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struct subchannel *sch = to_subchannel(dev);
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return sprintf(buf, "%01x\n", sch->st);
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}
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static DEVICE_ATTR_RO(type);
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static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
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char *buf)
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{
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struct subchannel *sch = to_subchannel(dev);
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return sprintf(buf, "css:t%01X\n", sch->st);
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}
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static DEVICE_ATTR_RO(modalias);
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static ssize_t driver_override_store(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t count)
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{
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struct subchannel *sch = to_subchannel(dev);
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int ret;
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ret = driver_set_override(dev, &sch->driver_override, buf, count);
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if (ret)
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return ret;
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return count;
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}
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static ssize_t driver_override_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct subchannel *sch = to_subchannel(dev);
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ssize_t len;
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device_lock(dev);
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len = snprintf(buf, PAGE_SIZE, "%s\n", sch->driver_override);
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device_unlock(dev);
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return len;
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}
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static DEVICE_ATTR_RW(driver_override);
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static struct attribute *subch_attrs[] = {
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&dev_attr_type.attr,
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&dev_attr_modalias.attr,
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&dev_attr_driver_override.attr,
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NULL,
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};
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static struct attribute_group subch_attr_group = {
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.attrs = subch_attrs,
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};
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static const struct attribute_group *default_subch_attr_groups[] = {
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&subch_attr_group,
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NULL,
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};
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static ssize_t chpids_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct subchannel *sch = to_subchannel(dev);
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struct chsc_ssd_info *ssd = &sch->ssd_info;
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ssize_t ret = 0;
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int mask;
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int chp;
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for (chp = 0; chp < 8; chp++) {
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mask = 0x80 >> chp;
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if (ssd->path_mask & mask)
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ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
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else
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ret += sprintf(buf + ret, "00 ");
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}
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ret += sprintf(buf + ret, "\n");
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return ret;
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}
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static DEVICE_ATTR_RO(chpids);
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static ssize_t pimpampom_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct subchannel *sch = to_subchannel(dev);
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struct pmcw *pmcw = &sch->schib.pmcw;
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return sprintf(buf, "%02x %02x %02x\n",
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pmcw->pim, pmcw->pam, pmcw->pom);
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}
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static DEVICE_ATTR_RO(pimpampom);
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static ssize_t dev_busid_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct subchannel *sch = to_subchannel(dev);
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struct pmcw *pmcw = &sch->schib.pmcw;
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if ((pmcw->st == SUBCHANNEL_TYPE_IO && pmcw->dnv) ||
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(pmcw->st == SUBCHANNEL_TYPE_MSG && pmcw->w))
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return sysfs_emit(buf, "0.%x.%04x\n", sch->schid.ssid,
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pmcw->dev);
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else
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return sysfs_emit(buf, "none\n");
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}
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static DEVICE_ATTR_RO(dev_busid);
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static struct attribute *io_subchannel_type_attrs[] = {
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&dev_attr_chpids.attr,
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&dev_attr_pimpampom.attr,
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&dev_attr_dev_busid.attr,
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NULL,
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};
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ATTRIBUTE_GROUPS(io_subchannel_type);
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static const struct device_type io_subchannel_type = {
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.groups = io_subchannel_type_groups,
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};
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int css_register_subchannel(struct subchannel *sch)
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{
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int ret;
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/* Initialize the subchannel structure */
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sch->dev.parent = &channel_subsystems[0]->device;
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sch->dev.bus = &css_bus_type;
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sch->dev.groups = default_subch_attr_groups;
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if (sch->st == SUBCHANNEL_TYPE_IO)
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sch->dev.type = &io_subchannel_type;
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css_update_ssd_info(sch);
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/* make it known to the system */
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ret = css_sch_device_register(sch);
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if (ret) {
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CIO_MSG_EVENT(0, "Could not register sch 0.%x.%04x: %d\n",
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sch->schid.ssid, sch->schid.sch_no, ret);
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return ret;
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}
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return ret;
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}
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static int css_probe_device(struct subchannel_id schid, struct schib *schib)
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{
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struct subchannel *sch;
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int ret;
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sch = css_alloc_subchannel(schid, schib);
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if (IS_ERR(sch))
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return PTR_ERR(sch);
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ret = css_register_subchannel(sch);
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if (ret)
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put_device(&sch->dev);
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return ret;
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}
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static int
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check_subchannel(struct device *dev, const void *data)
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{
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struct subchannel *sch;
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struct subchannel_id *schid = (void *)data;
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sch = to_subchannel(dev);
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return schid_equal(&sch->schid, schid);
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}
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struct subchannel *
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get_subchannel_by_schid(struct subchannel_id schid)
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{
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struct device *dev;
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dev = bus_find_device(&css_bus_type, NULL,
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&schid, check_subchannel);
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return dev ? to_subchannel(dev) : NULL;
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}
|
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|
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/**
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* css_sch_is_valid() - check if a subchannel is valid
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* @schib: subchannel information block for the subchannel
|
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*/
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int css_sch_is_valid(struct schib *schib)
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{
|
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if ((schib->pmcw.st == SUBCHANNEL_TYPE_IO) && !schib->pmcw.dnv)
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return 0;
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if ((schib->pmcw.st == SUBCHANNEL_TYPE_MSG) && !schib->pmcw.w)
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return 0;
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return 1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(css_sch_is_valid);
|
|
|
|
static int css_evaluate_new_subchannel(struct subchannel_id schid, int slow)
|
|
{
|
|
struct schib schib;
|
|
int ccode;
|
|
|
|
if (!slow) {
|
|
/* Will be done on the slow path. */
|
|
return -EAGAIN;
|
|
}
|
|
/*
|
|
* The first subchannel that is not-operational (ccode==3)
|
|
* indicates that there aren't any more devices available.
|
|
* If stsch gets an exception, it means the current subchannel set
|
|
* is not valid.
|
|
*/
|
|
ccode = stsch(schid, &schib);
|
|
if (ccode)
|
|
return (ccode == 3) ? -ENXIO : ccode;
|
|
|
|
return css_probe_device(schid, &schib);
|
|
}
|
|
|
|
static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (sch->driver) {
|
|
if (sch->driver->sch_event)
|
|
ret = sch->driver->sch_event(sch, slow);
|
|
else
|
|
dev_dbg(&sch->dev,
|
|
"Got subchannel machine check but "
|
|
"no sch_event handler provided.\n");
|
|
}
|
|
if (ret != 0 && ret != -EAGAIN) {
|
|
CIO_MSG_EVENT(2, "eval: sch 0.%x.%04x, rc=%d\n",
|
|
sch->schid.ssid, sch->schid.sch_no, ret);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void css_evaluate_subchannel(struct subchannel_id schid, int slow)
|
|
{
|
|
struct subchannel *sch;
|
|
int ret;
|
|
|
|
sch = get_subchannel_by_schid(schid);
|
|
if (sch) {
|
|
ret = css_evaluate_known_subchannel(sch, slow);
|
|
put_device(&sch->dev);
|
|
} else
|
|
ret = css_evaluate_new_subchannel(schid, slow);
|
|
if (ret == -EAGAIN)
|
|
css_schedule_eval(schid);
|
|
}
|
|
|
|
/**
|
|
* css_sched_sch_todo - schedule a subchannel operation
|
|
* @sch: subchannel
|
|
* @todo: todo
|
|
*
|
|
* Schedule the operation identified by @todo to be performed on the slow path
|
|
* workqueue. Do nothing if another operation with higher priority is already
|
|
* scheduled. Needs to be called with subchannel lock held.
|
|
*/
|
|
void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo)
|
|
{
|
|
CIO_MSG_EVENT(4, "sch_todo: sched sch=0.%x.%04x todo=%d\n",
|
|
sch->schid.ssid, sch->schid.sch_no, todo);
|
|
if (sch->todo >= todo)
|
|
return;
|
|
/* Get workqueue ref. */
|
|
if (!get_device(&sch->dev))
|
|
return;
|
|
sch->todo = todo;
|
|
if (!queue_work(cio_work_q, &sch->todo_work)) {
|
|
/* Already queued, release workqueue ref. */
|
|
put_device(&sch->dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(css_sched_sch_todo);
|
|
|
|
static void css_sch_todo(struct work_struct *work)
|
|
{
|
|
struct subchannel *sch;
|
|
enum sch_todo todo;
|
|
int ret;
|
|
|
|
sch = container_of(work, struct subchannel, todo_work);
|
|
/* Find out todo. */
|
|
spin_lock_irq(sch->lock);
|
|
todo = sch->todo;
|
|
CIO_MSG_EVENT(4, "sch_todo: sch=0.%x.%04x, todo=%d\n", sch->schid.ssid,
|
|
sch->schid.sch_no, todo);
|
|
sch->todo = SCH_TODO_NOTHING;
|
|
spin_unlock_irq(sch->lock);
|
|
/* Perform todo. */
|
|
switch (todo) {
|
|
case SCH_TODO_NOTHING:
|
|
break;
|
|
case SCH_TODO_EVAL:
|
|
ret = css_evaluate_known_subchannel(sch, 1);
|
|
if (ret == -EAGAIN) {
|
|
spin_lock_irq(sch->lock);
|
|
css_sched_sch_todo(sch, todo);
|
|
spin_unlock_irq(sch->lock);
|
|
}
|
|
break;
|
|
case SCH_TODO_UNREG:
|
|
css_sch_device_unregister(sch);
|
|
break;
|
|
}
|
|
/* Release workqueue ref. */
|
|
put_device(&sch->dev);
|
|
}
|
|
|
|
static struct idset *slow_subchannel_set;
|
|
static DEFINE_SPINLOCK(slow_subchannel_lock);
|
|
static DECLARE_WAIT_QUEUE_HEAD(css_eval_wq);
|
|
static atomic_t css_eval_scheduled;
|
|
|
|
static int __init slow_subchannel_init(void)
|
|
{
|
|
atomic_set(&css_eval_scheduled, 0);
|
|
slow_subchannel_set = idset_sch_new();
|
|
if (!slow_subchannel_set) {
|
|
CIO_MSG_EVENT(0, "could not allocate slow subchannel set\n");
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int slow_eval_known_fn(struct subchannel *sch, void *data)
|
|
{
|
|
int eval;
|
|
int rc;
|
|
|
|
spin_lock_irq(&slow_subchannel_lock);
|
|
eval = idset_sch_contains(slow_subchannel_set, sch->schid);
|
|
idset_sch_del(slow_subchannel_set, sch->schid);
|
|
spin_unlock_irq(&slow_subchannel_lock);
|
|
if (eval) {
|
|
rc = css_evaluate_known_subchannel(sch, 1);
|
|
if (rc == -EAGAIN)
|
|
css_schedule_eval(sch->schid);
|
|
/*
|
|
* The loop might take long time for platforms with lots of
|
|
* known devices. Allow scheduling here.
|
|
*/
|
|
cond_resched();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int slow_eval_unknown_fn(struct subchannel_id schid, void *data)
|
|
{
|
|
int eval;
|
|
int rc = 0;
|
|
|
|
spin_lock_irq(&slow_subchannel_lock);
|
|
eval = idset_sch_contains(slow_subchannel_set, schid);
|
|
idset_sch_del(slow_subchannel_set, schid);
|
|
spin_unlock_irq(&slow_subchannel_lock);
|
|
if (eval) {
|
|
rc = css_evaluate_new_subchannel(schid, 1);
|
|
switch (rc) {
|
|
case -EAGAIN:
|
|
css_schedule_eval(schid);
|
|
rc = 0;
|
|
break;
|
|
case -ENXIO:
|
|
case -ENOMEM:
|
|
case -EIO:
|
|
/* These should abort looping */
|
|
spin_lock_irq(&slow_subchannel_lock);
|
|
idset_sch_del_subseq(slow_subchannel_set, schid);
|
|
spin_unlock_irq(&slow_subchannel_lock);
|
|
break;
|
|
default:
|
|
rc = 0;
|
|
}
|
|
/* Allow scheduling here since the containing loop might
|
|
* take a while. */
|
|
cond_resched();
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static void css_slow_path_func(struct work_struct *unused)
|
|
{
|
|
unsigned long flags;
|
|
|
|
CIO_TRACE_EVENT(4, "slowpath");
|
|
for_each_subchannel_staged(slow_eval_known_fn, slow_eval_unknown_fn,
|
|
NULL);
|
|
spin_lock_irqsave(&slow_subchannel_lock, flags);
|
|
if (idset_is_empty(slow_subchannel_set)) {
|
|
atomic_set(&css_eval_scheduled, 0);
|
|
wake_up(&css_eval_wq);
|
|
}
|
|
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
|
|
}
|
|
|
|
static DECLARE_DELAYED_WORK(slow_path_work, css_slow_path_func);
|
|
struct workqueue_struct *cio_work_q;
|
|
|
|
void css_schedule_eval(struct subchannel_id schid)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&slow_subchannel_lock, flags);
|
|
idset_sch_add(slow_subchannel_set, schid);
|
|
atomic_set(&css_eval_scheduled, 1);
|
|
queue_delayed_work(cio_work_q, &slow_path_work, 0);
|
|
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
|
|
}
|
|
|
|
void css_schedule_eval_all(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&slow_subchannel_lock, flags);
|
|
idset_fill(slow_subchannel_set);
|
|
atomic_set(&css_eval_scheduled, 1);
|
|
queue_delayed_work(cio_work_q, &slow_path_work, 0);
|
|
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
|
|
}
|
|
|
|
static int __unset_registered(struct device *dev, void *data)
|
|
{
|
|
struct idset *set = data;
|
|
struct subchannel *sch = to_subchannel(dev);
|
|
|
|
idset_sch_del(set, sch->schid);
|
|
return 0;
|
|
}
|
|
|
|
static int __unset_online(struct device *dev, void *data)
|
|
{
|
|
struct idset *set = data;
|
|
struct subchannel *sch = to_subchannel(dev);
|
|
|
|
if (sch->st == SUBCHANNEL_TYPE_IO && sch->config.ena)
|
|
idset_sch_del(set, sch->schid);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void css_schedule_eval_cond(enum css_eval_cond cond, unsigned long delay)
|
|
{
|
|
unsigned long flags;
|
|
struct idset *set;
|
|
|
|
/* Find unregistered subchannels. */
|
|
set = idset_sch_new();
|
|
if (!set) {
|
|
/* Fallback. */
|
|
css_schedule_eval_all();
|
|
return;
|
|
}
|
|
idset_fill(set);
|
|
switch (cond) {
|
|
case CSS_EVAL_UNREG:
|
|
bus_for_each_dev(&css_bus_type, NULL, set, __unset_registered);
|
|
break;
|
|
case CSS_EVAL_NOT_ONLINE:
|
|
bus_for_each_dev(&css_bus_type, NULL, set, __unset_online);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
/* Apply to slow_subchannel_set. */
|
|
spin_lock_irqsave(&slow_subchannel_lock, flags);
|
|
idset_add_set(slow_subchannel_set, set);
|
|
atomic_set(&css_eval_scheduled, 1);
|
|
queue_delayed_work(cio_work_q, &slow_path_work, delay);
|
|
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
|
|
idset_free(set);
|
|
}
|
|
|
|
void css_wait_for_slow_path(void)
|
|
{
|
|
flush_workqueue(cio_work_q);
|
|
}
|
|
|
|
/* Schedule reprobing of all unregistered subchannels. */
|
|
void css_schedule_reprobe(void)
|
|
{
|
|
/* Schedule with a delay to allow merging of subsequent calls. */
|
|
css_schedule_eval_cond(CSS_EVAL_UNREG, 1 * HZ);
|
|
}
|
|
EXPORT_SYMBOL_GPL(css_schedule_reprobe);
|
|
|
|
/*
|
|
* Called from the machine check handler for subchannel report words.
|
|
*/
|
|
static void css_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
|
|
{
|
|
struct subchannel_id mchk_schid;
|
|
struct subchannel *sch;
|
|
|
|
if (overflow) {
|
|
css_schedule_eval_all();
|
|
return;
|
|
}
|
|
CIO_CRW_EVENT(2, "CRW0 reports slct=%d, oflw=%d, "
|
|
"chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
|
|
crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
|
|
crw0->erc, crw0->rsid);
|
|
if (crw1)
|
|
CIO_CRW_EVENT(2, "CRW1 reports slct=%d, oflw=%d, "
|
|
"chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
|
|
crw1->slct, crw1->oflw, crw1->chn, crw1->rsc,
|
|
crw1->anc, crw1->erc, crw1->rsid);
|
|
init_subchannel_id(&mchk_schid);
|
|
mchk_schid.sch_no = crw0->rsid;
|
|
if (crw1)
|
|
mchk_schid.ssid = (crw1->rsid >> 4) & 3;
|
|
|
|
if (crw0->erc == CRW_ERC_PMOD) {
|
|
sch = get_subchannel_by_schid(mchk_schid);
|
|
if (sch) {
|
|
css_update_ssd_info(sch);
|
|
put_device(&sch->dev);
|
|
}
|
|
}
|
|
/*
|
|
* Since we are always presented with IPI in the CRW, we have to
|
|
* use stsch() to find out if the subchannel in question has come
|
|
* or gone.
|
|
*/
|
|
css_evaluate_subchannel(mchk_schid, 0);
|
|
}
|
|
|
|
static void __init
|
|
css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
|
|
{
|
|
struct cpuid cpu_id;
|
|
|
|
if (css_general_characteristics.mcss) {
|
|
css->global_pgid.pgid_high.ext_cssid.version = 0x80;
|
|
css->global_pgid.pgid_high.ext_cssid.cssid =
|
|
css->id_valid ? css->cssid : 0;
|
|
} else {
|
|
css->global_pgid.pgid_high.cpu_addr = stap();
|
|
}
|
|
get_cpu_id(&cpu_id);
|
|
css->global_pgid.cpu_id = cpu_id.ident;
|
|
css->global_pgid.cpu_model = cpu_id.machine;
|
|
css->global_pgid.tod_high = tod_high;
|
|
}
|
|
|
|
static void channel_subsystem_release(struct device *dev)
|
|
{
|
|
struct channel_subsystem *css = to_css(dev);
|
|
|
|
mutex_destroy(&css->mutex);
|
|
kfree(css);
|
|
}
|
|
|
|
static ssize_t real_cssid_show(struct device *dev, struct device_attribute *a,
|
|
char *buf)
|
|
{
|
|
struct channel_subsystem *css = to_css(dev);
|
|
|
|
if (!css->id_valid)
|
|
return -EINVAL;
|
|
|
|
return sprintf(buf, "%x\n", css->cssid);
|
|
}
|
|
static DEVICE_ATTR_RO(real_cssid);
|
|
|
|
static ssize_t rescan_store(struct device *dev, struct device_attribute *a,
|
|
const char *buf, size_t count)
|
|
{
|
|
CIO_TRACE_EVENT(4, "usr-rescan");
|
|
|
|
css_schedule_eval_all();
|
|
css_complete_work();
|
|
|
|
return count;
|
|
}
|
|
static DEVICE_ATTR_WO(rescan);
|
|
|
|
static ssize_t cm_enable_show(struct device *dev, struct device_attribute *a,
|
|
char *buf)
|
|
{
|
|
struct channel_subsystem *css = to_css(dev);
|
|
int ret;
|
|
|
|
mutex_lock(&css->mutex);
|
|
ret = sprintf(buf, "%x\n", css->cm_enabled);
|
|
mutex_unlock(&css->mutex);
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t cm_enable_store(struct device *dev, struct device_attribute *a,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct channel_subsystem *css = to_css(dev);
|
|
unsigned long val;
|
|
int ret;
|
|
|
|
ret = kstrtoul(buf, 16, &val);
|
|
if (ret)
|
|
return ret;
|
|
mutex_lock(&css->mutex);
|
|
switch (val) {
|
|
case 0:
|
|
ret = css->cm_enabled ? chsc_secm(css, 0) : 0;
|
|
break;
|
|
case 1:
|
|
ret = css->cm_enabled ? 0 : chsc_secm(css, 1);
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
}
|
|
mutex_unlock(&css->mutex);
|
|
return ret < 0 ? ret : count;
|
|
}
|
|
static DEVICE_ATTR_RW(cm_enable);
|
|
|
|
static umode_t cm_enable_mode(struct kobject *kobj, struct attribute *attr,
|
|
int index)
|
|
{
|
|
return css_chsc_characteristics.secm ? attr->mode : 0;
|
|
}
|
|
|
|
static struct attribute *cssdev_attrs[] = {
|
|
&dev_attr_real_cssid.attr,
|
|
&dev_attr_rescan.attr,
|
|
NULL,
|
|
};
|
|
|
|
static struct attribute_group cssdev_attr_group = {
|
|
.attrs = cssdev_attrs,
|
|
};
|
|
|
|
static struct attribute *cssdev_cm_attrs[] = {
|
|
&dev_attr_cm_enable.attr,
|
|
NULL,
|
|
};
|
|
|
|
static struct attribute_group cssdev_cm_attr_group = {
|
|
.attrs = cssdev_cm_attrs,
|
|
.is_visible = cm_enable_mode,
|
|
};
|
|
|
|
static const struct attribute_group *cssdev_attr_groups[] = {
|
|
&cssdev_attr_group,
|
|
&cssdev_cm_attr_group,
|
|
NULL,
|
|
};
|
|
|
|
static int __init setup_css(int nr)
|
|
{
|
|
struct channel_subsystem *css;
|
|
int ret;
|
|
|
|
css = kzalloc(sizeof(*css), GFP_KERNEL);
|
|
if (!css)
|
|
return -ENOMEM;
|
|
|
|
channel_subsystems[nr] = css;
|
|
dev_set_name(&css->device, "css%x", nr);
|
|
css->device.groups = cssdev_attr_groups;
|
|
css->device.release = channel_subsystem_release;
|
|
/*
|
|
* We currently allocate notifier bits with this (using
|
|
* css->device as the device argument with the DMA API)
|
|
* and are fine with 64 bit addresses.
|
|
*/
|
|
ret = dma_coerce_mask_and_coherent(&css->device, DMA_BIT_MASK(64));
|
|
if (ret) {
|
|
kfree(css);
|
|
goto out_err;
|
|
}
|
|
|
|
mutex_init(&css->mutex);
|
|
ret = chsc_get_cssid_iid(nr, &css->cssid, &css->iid);
|
|
if (!ret) {
|
|
css->id_valid = true;
|
|
pr_info("Partition identifier %01x.%01x\n", css->cssid,
|
|
css->iid);
|
|
}
|
|
css_generate_pgid(css, (u32) (get_tod_clock() >> 32));
|
|
|
|
ret = device_register(&css->device);
|
|
if (ret) {
|
|
put_device(&css->device);
|
|
goto out_err;
|
|
}
|
|
|
|
css->pseudo_subchannel = kzalloc(sizeof(*css->pseudo_subchannel),
|
|
GFP_KERNEL);
|
|
if (!css->pseudo_subchannel) {
|
|
device_unregister(&css->device);
|
|
ret = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
|
|
css->pseudo_subchannel->dev.parent = &css->device;
|
|
css->pseudo_subchannel->dev.release = css_subchannel_release;
|
|
mutex_init(&css->pseudo_subchannel->reg_mutex);
|
|
ret = css_sch_create_locks(css->pseudo_subchannel);
|
|
if (ret) {
|
|
kfree(css->pseudo_subchannel);
|
|
device_unregister(&css->device);
|
|
goto out_err;
|
|
}
|
|
|
|
dev_set_name(&css->pseudo_subchannel->dev, "defunct");
|
|
ret = device_register(&css->pseudo_subchannel->dev);
|
|
if (ret) {
|
|
put_device(&css->pseudo_subchannel->dev);
|
|
device_unregister(&css->device);
|
|
goto out_err;
|
|
}
|
|
|
|
return ret;
|
|
out_err:
|
|
channel_subsystems[nr] = NULL;
|
|
return ret;
|
|
}
|
|
|
|
static int css_reboot_event(struct notifier_block *this,
|
|
unsigned long event,
|
|
void *ptr)
|
|
{
|
|
struct channel_subsystem *css;
|
|
int ret;
|
|
|
|
ret = NOTIFY_DONE;
|
|
for_each_css(css) {
|
|
mutex_lock(&css->mutex);
|
|
if (css->cm_enabled)
|
|
if (chsc_secm(css, 0))
|
|
ret = NOTIFY_BAD;
|
|
mutex_unlock(&css->mutex);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static struct notifier_block css_reboot_notifier = {
|
|
.notifier_call = css_reboot_event,
|
|
};
|
|
|
|
#define CIO_DMA_GFP (GFP_KERNEL | __GFP_ZERO)
|
|
static struct gen_pool *cio_dma_pool;
|
|
|
|
/* Currently cio supports only a single css */
|
|
struct device *cio_get_dma_css_dev(void)
|
|
{
|
|
return &channel_subsystems[0]->device;
|
|
}
|
|
|
|
struct gen_pool *cio_gp_dma_create(struct device *dma_dev, int nr_pages)
|
|
{
|
|
struct gen_pool *gp_dma;
|
|
void *cpu_addr;
|
|
dma_addr_t dma_addr;
|
|
int i;
|
|
|
|
gp_dma = gen_pool_create(3, -1);
|
|
if (!gp_dma)
|
|
return NULL;
|
|
for (i = 0; i < nr_pages; ++i) {
|
|
cpu_addr = dma_alloc_coherent(dma_dev, PAGE_SIZE, &dma_addr,
|
|
CIO_DMA_GFP);
|
|
if (!cpu_addr)
|
|
return gp_dma;
|
|
gen_pool_add_virt(gp_dma, (unsigned long) cpu_addr,
|
|
dma_addr, PAGE_SIZE, -1);
|
|
}
|
|
return gp_dma;
|
|
}
|
|
|
|
static void __gp_dma_free_dma(struct gen_pool *pool,
|
|
struct gen_pool_chunk *chunk, void *data)
|
|
{
|
|
size_t chunk_size = chunk->end_addr - chunk->start_addr + 1;
|
|
|
|
dma_free_coherent((struct device *) data, chunk_size,
|
|
(void *) chunk->start_addr,
|
|
(dma_addr_t) chunk->phys_addr);
|
|
}
|
|
|
|
void cio_gp_dma_destroy(struct gen_pool *gp_dma, struct device *dma_dev)
|
|
{
|
|
if (!gp_dma)
|
|
return;
|
|
/* this is quite ugly but no better idea */
|
|
gen_pool_for_each_chunk(gp_dma, __gp_dma_free_dma, dma_dev);
|
|
gen_pool_destroy(gp_dma);
|
|
}
|
|
|
|
static int cio_dma_pool_init(void)
|
|
{
|
|
/* No need to free up the resources: compiled in */
|
|
cio_dma_pool = cio_gp_dma_create(cio_get_dma_css_dev(), 1);
|
|
if (!cio_dma_pool)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
void *cio_gp_dma_zalloc(struct gen_pool *gp_dma, struct device *dma_dev,
|
|
size_t size)
|
|
{
|
|
dma_addr_t dma_addr;
|
|
unsigned long addr;
|
|
size_t chunk_size;
|
|
|
|
if (!gp_dma)
|
|
return NULL;
|
|
addr = gen_pool_alloc(gp_dma, size);
|
|
while (!addr) {
|
|
chunk_size = round_up(size, PAGE_SIZE);
|
|
addr = (unsigned long) dma_alloc_coherent(dma_dev,
|
|
chunk_size, &dma_addr, CIO_DMA_GFP);
|
|
if (!addr)
|
|
return NULL;
|
|
gen_pool_add_virt(gp_dma, addr, dma_addr, chunk_size, -1);
|
|
addr = gen_pool_alloc(gp_dma, size);
|
|
}
|
|
return (void *) addr;
|
|
}
|
|
|
|
void cio_gp_dma_free(struct gen_pool *gp_dma, void *cpu_addr, size_t size)
|
|
{
|
|
if (!cpu_addr)
|
|
return;
|
|
memset(cpu_addr, 0, size);
|
|
gen_pool_free(gp_dma, (unsigned long) cpu_addr, size);
|
|
}
|
|
|
|
/*
|
|
* Allocate dma memory from the css global pool. Intended for memory not
|
|
* specific to any single device within the css. The allocated memory
|
|
* is not guaranteed to be 31-bit addressable.
|
|
*
|
|
* Caution: Not suitable for early stuff like console.
|
|
*/
|
|
void *cio_dma_zalloc(size_t size)
|
|
{
|
|
return cio_gp_dma_zalloc(cio_dma_pool, cio_get_dma_css_dev(), size);
|
|
}
|
|
|
|
void cio_dma_free(void *cpu_addr, size_t size)
|
|
{
|
|
cio_gp_dma_free(cio_dma_pool, cpu_addr, size);
|
|
}
|
|
|
|
/*
|
|
* Now that the driver core is running, we can setup our channel subsystem.
|
|
* The struct subchannel's are created during probing.
|
|
*/
|
|
static int __init css_bus_init(void)
|
|
{
|
|
int ret, i;
|
|
|
|
ret = chsc_init();
|
|
if (ret)
|
|
return ret;
|
|
|
|
chsc_determine_css_characteristics();
|
|
/* Try to enable MSS. */
|
|
ret = chsc_enable_facility(CHSC_SDA_OC_MSS);
|
|
if (ret)
|
|
max_ssid = 0;
|
|
else /* Success. */
|
|
max_ssid = __MAX_SSID;
|
|
|
|
ret = slow_subchannel_init();
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = crw_register_handler(CRW_RSC_SCH, css_process_crw);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if ((ret = bus_register(&css_bus_type)))
|
|
goto out;
|
|
|
|
/* Setup css structure. */
|
|
for (i = 0; i <= MAX_CSS_IDX; i++) {
|
|
ret = setup_css(i);
|
|
if (ret)
|
|
goto out_unregister;
|
|
}
|
|
ret = register_reboot_notifier(&css_reboot_notifier);
|
|
if (ret)
|
|
goto out_unregister;
|
|
ret = cio_dma_pool_init();
|
|
if (ret)
|
|
goto out_unregister_rn;
|
|
airq_init();
|
|
css_init_done = 1;
|
|
|
|
/* Enable default isc for I/O subchannels. */
|
|
isc_register(IO_SCH_ISC);
|
|
|
|
return 0;
|
|
out_unregister_rn:
|
|
unregister_reboot_notifier(&css_reboot_notifier);
|
|
out_unregister:
|
|
while (i-- > 0) {
|
|
struct channel_subsystem *css = channel_subsystems[i];
|
|
device_unregister(&css->pseudo_subchannel->dev);
|
|
device_unregister(&css->device);
|
|
}
|
|
bus_unregister(&css_bus_type);
|
|
out:
|
|
crw_unregister_handler(CRW_RSC_SCH);
|
|
idset_free(slow_subchannel_set);
|
|
chsc_init_cleanup();
|
|
pr_alert("The CSS device driver initialization failed with "
|
|
"errno=%d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
static void __init css_bus_cleanup(void)
|
|
{
|
|
struct channel_subsystem *css;
|
|
|
|
for_each_css(css) {
|
|
device_unregister(&css->pseudo_subchannel->dev);
|
|
device_unregister(&css->device);
|
|
}
|
|
bus_unregister(&css_bus_type);
|
|
crw_unregister_handler(CRW_RSC_SCH);
|
|
idset_free(slow_subchannel_set);
|
|
chsc_init_cleanup();
|
|
isc_unregister(IO_SCH_ISC);
|
|
}
|
|
|
|
static int __init channel_subsystem_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = css_bus_init();
|
|
if (ret)
|
|
return ret;
|
|
cio_work_q = create_singlethread_workqueue("cio");
|
|
if (!cio_work_q) {
|
|
ret = -ENOMEM;
|
|
goto out_bus;
|
|
}
|
|
ret = io_subchannel_init();
|
|
if (ret)
|
|
goto out_wq;
|
|
|
|
/* Register subchannels which are already in use. */
|
|
cio_register_early_subchannels();
|
|
/* Start initial subchannel evaluation. */
|
|
css_schedule_eval_all();
|
|
|
|
return ret;
|
|
out_wq:
|
|
destroy_workqueue(cio_work_q);
|
|
out_bus:
|
|
css_bus_cleanup();
|
|
return ret;
|
|
}
|
|
subsys_initcall(channel_subsystem_init);
|
|
|
|
static int css_settle(struct device_driver *drv, void *unused)
|
|
{
|
|
struct css_driver *cssdrv = to_cssdriver(drv);
|
|
|
|
if (cssdrv->settle)
|
|
return cssdrv->settle();
|
|
return 0;
|
|
}
|
|
|
|
int css_complete_work(void)
|
|
{
|
|
int ret;
|
|
|
|
/* Wait for the evaluation of subchannels to finish. */
|
|
ret = wait_event_interruptible(css_eval_wq,
|
|
atomic_read(&css_eval_scheduled) == 0);
|
|
if (ret)
|
|
return -EINTR;
|
|
flush_workqueue(cio_work_q);
|
|
/* Wait for the subchannel type specific initialization to finish */
|
|
return bus_for_each_drv(&css_bus_type, NULL, NULL, css_settle);
|
|
}
|
|
|
|
|
|
/*
|
|
* Wait for the initialization of devices to finish, to make sure we are
|
|
* done with our setup if the search for the root device starts.
|
|
*/
|
|
static int __init channel_subsystem_init_sync(void)
|
|
{
|
|
css_complete_work();
|
|
return 0;
|
|
}
|
|
subsys_initcall_sync(channel_subsystem_init_sync);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static ssize_t cio_settle_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
int ret;
|
|
|
|
/* Handle pending CRW's. */
|
|
crw_wait_for_channel_report();
|
|
ret = css_complete_work();
|
|
|
|
return ret ? ret : count;
|
|
}
|
|
|
|
static const struct proc_ops cio_settle_proc_ops = {
|
|
.proc_open = nonseekable_open,
|
|
.proc_write = cio_settle_write,
|
|
.proc_lseek = no_llseek,
|
|
};
|
|
|
|
static int __init cio_settle_init(void)
|
|
{
|
|
struct proc_dir_entry *entry;
|
|
|
|
entry = proc_create("cio_settle", S_IWUSR, NULL, &cio_settle_proc_ops);
|
|
if (!entry)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
device_initcall(cio_settle_init);
|
|
#endif /*CONFIG_PROC_FS*/
|
|
|
|
int sch_is_pseudo_sch(struct subchannel *sch)
|
|
{
|
|
if (!sch->dev.parent)
|
|
return 0;
|
|
return sch == to_css(sch->dev.parent)->pseudo_subchannel;
|
|
}
|
|
|
|
static int css_bus_match(struct device *dev, struct device_driver *drv)
|
|
{
|
|
struct subchannel *sch = to_subchannel(dev);
|
|
struct css_driver *driver = to_cssdriver(drv);
|
|
struct css_device_id *id;
|
|
|
|
/* When driver_override is set, only bind to the matching driver */
|
|
if (sch->driver_override && strcmp(sch->driver_override, drv->name))
|
|
return 0;
|
|
|
|
for (id = driver->subchannel_type; id->match_flags; id++) {
|
|
if (sch->st == id->type)
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int css_probe(struct device *dev)
|
|
{
|
|
struct subchannel *sch;
|
|
int ret;
|
|
|
|
sch = to_subchannel(dev);
|
|
sch->driver = to_cssdriver(dev->driver);
|
|
ret = sch->driver->probe ? sch->driver->probe(sch) : 0;
|
|
if (ret)
|
|
sch->driver = NULL;
|
|
return ret;
|
|
}
|
|
|
|
static void css_remove(struct device *dev)
|
|
{
|
|
struct subchannel *sch;
|
|
|
|
sch = to_subchannel(dev);
|
|
if (sch->driver->remove)
|
|
sch->driver->remove(sch);
|
|
sch->driver = NULL;
|
|
}
|
|
|
|
static void css_shutdown(struct device *dev)
|
|
{
|
|
struct subchannel *sch;
|
|
|
|
sch = to_subchannel(dev);
|
|
if (sch->driver && sch->driver->shutdown)
|
|
sch->driver->shutdown(sch);
|
|
}
|
|
|
|
static int css_uevent(struct device *dev, struct kobj_uevent_env *env)
|
|
{
|
|
struct subchannel *sch = to_subchannel(dev);
|
|
int ret;
|
|
|
|
ret = add_uevent_var(env, "ST=%01X", sch->st);
|
|
if (ret)
|
|
return ret;
|
|
ret = add_uevent_var(env, "MODALIAS=css:t%01X", sch->st);
|
|
return ret;
|
|
}
|
|
|
|
static struct bus_type css_bus_type = {
|
|
.name = "css",
|
|
.match = css_bus_match,
|
|
.probe = css_probe,
|
|
.remove = css_remove,
|
|
.shutdown = css_shutdown,
|
|
.uevent = css_uevent,
|
|
};
|
|
|
|
/**
|
|
* css_driver_register - register a css driver
|
|
* @cdrv: css driver to register
|
|
*
|
|
* This is mainly a wrapper around driver_register that sets name
|
|
* and bus_type in the embedded struct device_driver correctly.
|
|
*/
|
|
int css_driver_register(struct css_driver *cdrv)
|
|
{
|
|
cdrv->drv.bus = &css_bus_type;
|
|
return driver_register(&cdrv->drv);
|
|
}
|
|
EXPORT_SYMBOL_GPL(css_driver_register);
|
|
|
|
/**
|
|
* css_driver_unregister - unregister a css driver
|
|
* @cdrv: css driver to unregister
|
|
*
|
|
* This is a wrapper around driver_unregister.
|
|
*/
|
|
void css_driver_unregister(struct css_driver *cdrv)
|
|
{
|
|
driver_unregister(&cdrv->drv);
|
|
}
|
|
EXPORT_SYMBOL_GPL(css_driver_unregister);
|