364 lines
8.8 KiB
C
364 lines
8.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* VFIO based Physical Subchannel device driver
|
|
*
|
|
* Copyright IBM Corp. 2017
|
|
* Copyright Red Hat, Inc. 2019
|
|
*
|
|
* Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
|
|
* Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
|
|
* Cornelia Huck <cohuck@redhat.com>
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/device.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/uuid.h>
|
|
#include <linux/mdev.h>
|
|
|
|
#include <asm/isc.h>
|
|
|
|
#include "ioasm.h"
|
|
#include "css.h"
|
|
#include "vfio_ccw_private.h"
|
|
|
|
struct workqueue_struct *vfio_ccw_work_q;
|
|
static struct kmem_cache *vfio_ccw_io_region;
|
|
static struct kmem_cache *vfio_ccw_cmd_region;
|
|
|
|
debug_info_t *vfio_ccw_debug_msg_id;
|
|
debug_info_t *vfio_ccw_debug_trace_id;
|
|
|
|
/*
|
|
* Helpers
|
|
*/
|
|
int vfio_ccw_sch_quiesce(struct subchannel *sch)
|
|
{
|
|
struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
|
|
DECLARE_COMPLETION_ONSTACK(completion);
|
|
int iretry, ret = 0;
|
|
|
|
spin_lock_irq(sch->lock);
|
|
if (!sch->schib.pmcw.ena)
|
|
goto out_unlock;
|
|
ret = cio_disable_subchannel(sch);
|
|
if (ret != -EBUSY)
|
|
goto out_unlock;
|
|
|
|
iretry = 255;
|
|
do {
|
|
|
|
ret = cio_cancel_halt_clear(sch, &iretry);
|
|
|
|
if (ret == -EIO) {
|
|
pr_err("vfio_ccw: could not quiesce subchannel 0.%x.%04x!\n",
|
|
sch->schid.ssid, sch->schid.sch_no);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Flush all I/O and wait for
|
|
* cancel/halt/clear completion.
|
|
*/
|
|
private->completion = &completion;
|
|
spin_unlock_irq(sch->lock);
|
|
|
|
if (ret == -EBUSY)
|
|
wait_for_completion_timeout(&completion, 3*HZ);
|
|
|
|
private->completion = NULL;
|
|
flush_workqueue(vfio_ccw_work_q);
|
|
spin_lock_irq(sch->lock);
|
|
ret = cio_disable_subchannel(sch);
|
|
} while (ret == -EBUSY);
|
|
out_unlock:
|
|
private->state = VFIO_CCW_STATE_NOT_OPER;
|
|
spin_unlock_irq(sch->lock);
|
|
return ret;
|
|
}
|
|
|
|
static void vfio_ccw_sch_io_todo(struct work_struct *work)
|
|
{
|
|
struct vfio_ccw_private *private;
|
|
struct irb *irb;
|
|
bool is_final;
|
|
|
|
private = container_of(work, struct vfio_ccw_private, io_work);
|
|
irb = &private->irb;
|
|
|
|
is_final = !(scsw_actl(&irb->scsw) &
|
|
(SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT));
|
|
if (scsw_is_solicited(&irb->scsw)) {
|
|
cp_update_scsw(&private->cp, &irb->scsw);
|
|
if (is_final && private->state == VFIO_CCW_STATE_CP_PENDING)
|
|
cp_free(&private->cp);
|
|
}
|
|
mutex_lock(&private->io_mutex);
|
|
memcpy(private->io_region->irb_area, irb, sizeof(*irb));
|
|
mutex_unlock(&private->io_mutex);
|
|
|
|
if (private->mdev && is_final)
|
|
private->state = VFIO_CCW_STATE_IDLE;
|
|
|
|
if (private->io_trigger)
|
|
eventfd_signal(private->io_trigger, 1);
|
|
}
|
|
|
|
/*
|
|
* Css driver callbacks
|
|
*/
|
|
static void vfio_ccw_sch_irq(struct subchannel *sch)
|
|
{
|
|
struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
|
|
|
|
inc_irq_stat(IRQIO_CIO);
|
|
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
|
|
}
|
|
|
|
static int vfio_ccw_sch_probe(struct subchannel *sch)
|
|
{
|
|
struct pmcw *pmcw = &sch->schib.pmcw;
|
|
struct vfio_ccw_private *private;
|
|
int ret = -ENOMEM;
|
|
|
|
if (pmcw->qf) {
|
|
dev_warn(&sch->dev, "vfio: ccw: does not support QDIO: %s\n",
|
|
dev_name(&sch->dev));
|
|
return -ENODEV;
|
|
}
|
|
|
|
private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
|
|
if (!private)
|
|
return -ENOMEM;
|
|
|
|
private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
|
|
GFP_KERNEL);
|
|
if (!private->cp.guest_cp)
|
|
goto out_free;
|
|
|
|
private->io_region = kmem_cache_zalloc(vfio_ccw_io_region,
|
|
GFP_KERNEL | GFP_DMA);
|
|
if (!private->io_region)
|
|
goto out_free;
|
|
|
|
private->cmd_region = kmem_cache_zalloc(vfio_ccw_cmd_region,
|
|
GFP_KERNEL | GFP_DMA);
|
|
if (!private->cmd_region)
|
|
goto out_free;
|
|
|
|
private->sch = sch;
|
|
dev_set_drvdata(&sch->dev, private);
|
|
mutex_init(&private->io_mutex);
|
|
|
|
spin_lock_irq(sch->lock);
|
|
private->state = VFIO_CCW_STATE_NOT_OPER;
|
|
sch->isc = VFIO_CCW_ISC;
|
|
ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch);
|
|
spin_unlock_irq(sch->lock);
|
|
if (ret)
|
|
goto out_free;
|
|
|
|
INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
|
|
atomic_set(&private->avail, 1);
|
|
private->state = VFIO_CCW_STATE_STANDBY;
|
|
|
|
ret = vfio_ccw_mdev_reg(sch);
|
|
if (ret)
|
|
goto out_disable;
|
|
|
|
VFIO_CCW_MSG_EVENT(4, "bound to subchannel %x.%x.%04x\n",
|
|
sch->schid.cssid, sch->schid.ssid,
|
|
sch->schid.sch_no);
|
|
return 0;
|
|
|
|
out_disable:
|
|
cio_disable_subchannel(sch);
|
|
out_free:
|
|
dev_set_drvdata(&sch->dev, NULL);
|
|
if (private->cmd_region)
|
|
kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
|
|
if (private->io_region)
|
|
kmem_cache_free(vfio_ccw_io_region, private->io_region);
|
|
kfree(private->cp.guest_cp);
|
|
kfree(private);
|
|
return ret;
|
|
}
|
|
|
|
static int vfio_ccw_sch_remove(struct subchannel *sch)
|
|
{
|
|
struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
|
|
|
|
vfio_ccw_sch_quiesce(sch);
|
|
|
|
vfio_ccw_mdev_unreg(sch);
|
|
|
|
dev_set_drvdata(&sch->dev, NULL);
|
|
|
|
kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
|
|
kmem_cache_free(vfio_ccw_io_region, private->io_region);
|
|
kfree(private->cp.guest_cp);
|
|
kfree(private);
|
|
|
|
VFIO_CCW_MSG_EVENT(4, "unbound from subchannel %x.%x.%04x\n",
|
|
sch->schid.cssid, sch->schid.ssid,
|
|
sch->schid.sch_no);
|
|
return 0;
|
|
}
|
|
|
|
static void vfio_ccw_sch_shutdown(struct subchannel *sch)
|
|
{
|
|
vfio_ccw_sch_quiesce(sch);
|
|
}
|
|
|
|
/**
|
|
* vfio_ccw_sch_event - process subchannel event
|
|
* @sch: subchannel
|
|
* @process: non-zero if function is called in process context
|
|
*
|
|
* An unspecified event occurred for this subchannel. Adjust data according
|
|
* to the current operational state of the subchannel. Return zero when the
|
|
* event has been handled sufficiently or -EAGAIN when this function should
|
|
* be called again in process context.
|
|
*/
|
|
static int vfio_ccw_sch_event(struct subchannel *sch, int process)
|
|
{
|
|
struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
|
|
unsigned long flags;
|
|
int rc = -EAGAIN;
|
|
|
|
spin_lock_irqsave(sch->lock, flags);
|
|
if (!device_is_registered(&sch->dev))
|
|
goto out_unlock;
|
|
|
|
if (work_pending(&sch->todo_work))
|
|
goto out_unlock;
|
|
|
|
if (cio_update_schib(sch)) {
|
|
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER);
|
|
rc = 0;
|
|
goto out_unlock;
|
|
}
|
|
|
|
private = dev_get_drvdata(&sch->dev);
|
|
if (private->state == VFIO_CCW_STATE_NOT_OPER) {
|
|
private->state = private->mdev ? VFIO_CCW_STATE_IDLE :
|
|
VFIO_CCW_STATE_STANDBY;
|
|
}
|
|
rc = 0;
|
|
|
|
out_unlock:
|
|
spin_unlock_irqrestore(sch->lock, flags);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static struct css_device_id vfio_ccw_sch_ids[] = {
|
|
{ .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
|
|
{ /* end of list */ },
|
|
};
|
|
MODULE_DEVICE_TABLE(css, vfio_ccw_sch_ids);
|
|
|
|
static struct css_driver vfio_ccw_sch_driver = {
|
|
.drv = {
|
|
.name = "vfio_ccw",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.subchannel_type = vfio_ccw_sch_ids,
|
|
.irq = vfio_ccw_sch_irq,
|
|
.probe = vfio_ccw_sch_probe,
|
|
.remove = vfio_ccw_sch_remove,
|
|
.shutdown = vfio_ccw_sch_shutdown,
|
|
.sch_event = vfio_ccw_sch_event,
|
|
};
|
|
|
|
static int __init vfio_ccw_debug_init(void)
|
|
{
|
|
vfio_ccw_debug_msg_id = debug_register("vfio_ccw_msg", 16, 1,
|
|
11 * sizeof(long));
|
|
if (!vfio_ccw_debug_msg_id)
|
|
goto out_unregister;
|
|
debug_register_view(vfio_ccw_debug_msg_id, &debug_sprintf_view);
|
|
debug_set_level(vfio_ccw_debug_msg_id, 2);
|
|
vfio_ccw_debug_trace_id = debug_register("vfio_ccw_trace", 16, 1, 16);
|
|
if (!vfio_ccw_debug_trace_id)
|
|
goto out_unregister;
|
|
debug_register_view(vfio_ccw_debug_trace_id, &debug_hex_ascii_view);
|
|
debug_set_level(vfio_ccw_debug_trace_id, 2);
|
|
return 0;
|
|
|
|
out_unregister:
|
|
debug_unregister(vfio_ccw_debug_msg_id);
|
|
debug_unregister(vfio_ccw_debug_trace_id);
|
|
return -1;
|
|
}
|
|
|
|
static void vfio_ccw_debug_exit(void)
|
|
{
|
|
debug_unregister(vfio_ccw_debug_msg_id);
|
|
debug_unregister(vfio_ccw_debug_trace_id);
|
|
}
|
|
|
|
static int __init vfio_ccw_sch_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = vfio_ccw_debug_init();
|
|
if (ret)
|
|
return ret;
|
|
|
|
vfio_ccw_work_q = create_singlethread_workqueue("vfio-ccw");
|
|
if (!vfio_ccw_work_q) {
|
|
ret = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
|
|
vfio_ccw_io_region = kmem_cache_create_usercopy("vfio_ccw_io_region",
|
|
sizeof(struct ccw_io_region), 0,
|
|
SLAB_ACCOUNT, 0,
|
|
sizeof(struct ccw_io_region), NULL);
|
|
if (!vfio_ccw_io_region) {
|
|
ret = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
|
|
vfio_ccw_cmd_region = kmem_cache_create_usercopy("vfio_ccw_cmd_region",
|
|
sizeof(struct ccw_cmd_region), 0,
|
|
SLAB_ACCOUNT, 0,
|
|
sizeof(struct ccw_cmd_region), NULL);
|
|
if (!vfio_ccw_cmd_region) {
|
|
ret = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
|
|
isc_register(VFIO_CCW_ISC);
|
|
ret = css_driver_register(&vfio_ccw_sch_driver);
|
|
if (ret) {
|
|
isc_unregister(VFIO_CCW_ISC);
|
|
goto out_err;
|
|
}
|
|
|
|
return ret;
|
|
|
|
out_err:
|
|
kmem_cache_destroy(vfio_ccw_cmd_region);
|
|
kmem_cache_destroy(vfio_ccw_io_region);
|
|
destroy_workqueue(vfio_ccw_work_q);
|
|
vfio_ccw_debug_exit();
|
|
return ret;
|
|
}
|
|
|
|
static void __exit vfio_ccw_sch_exit(void)
|
|
{
|
|
css_driver_unregister(&vfio_ccw_sch_driver);
|
|
isc_unregister(VFIO_CCW_ISC);
|
|
kmem_cache_destroy(vfio_ccw_io_region);
|
|
kmem_cache_destroy(vfio_ccw_cmd_region);
|
|
destroy_workqueue(vfio_ccw_work_q);
|
|
vfio_ccw_debug_exit();
|
|
}
|
|
module_init(vfio_ccw_sch_init);
|
|
module_exit(vfio_ccw_sch_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|