path: root/drivers/s390/cio/chsc.c

/*
 *  drivers/s390/cio/chsc.c
 *   S/390 common I/O routines -- channel subsystem call
 *
 *    Copyright IBM Corp. 1999,2010
 *    Author(s): Ingo Adlung (adlung@de.ibm.com)
 *		 Cornelia Huck (cornelia.huck@de.ibm.com)
 *		 Arnd Bergmann (arndb@de.ibm.com)
 */

#define KMSG_COMPONENT "cio"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/device.h>

#include <asm/cio.h>
#include <asm/chpid.h>
#include <asm/chsc.h>
#include <asm/crw.h>

#include "css.h"
#include "cio.h"
#include "cio_debug.h"
#include "ioasm.h"
#include "chp.h"
#include "chsc.h"

static void *sei_page;
static void *chsc_page;
static DEFINE_SPINLOCK(chsc_page_lock);

/**
 * chsc_error_from_response() - convert a chsc response to an error
 * @response: chsc response code
 *
 * Returns an appropriate Linux error code for @response.
 */
int chsc_error_from_response(int response)
{
	switch (response) {
	case 0x0001:
		return 0;
	case 0x0002:
	case 0x0003:
	case 0x0006:
	case 0x0007:
	case 0x0008:
	case 0x000a:
	case 0x0104:
		return -EINVAL;
	case 0x0004:
		return -EOPNOTSUPP;
	default:
		return -EIO;
	}
}
EXPORT_SYMBOL_GPL(chsc_error_from_response);

struct chsc_ssd_area {
	struct chsc_header request;
	u16 :10;
	u16 ssid:2;
	u16 :4;
	u16 f_sch;	  /* first subchannel */
	u16 :16;
	u16 l_sch;	  /* last subchannel */
	u32 :32;
	struct chsc_header response;
	u32 :32;
	u8 sch_valid : 1;
	u8 dev_valid : 1;
	u8 st	     : 3; /* subchannel type */
	u8 zeroes    : 3;
	u8  unit_addr;	  /* unit address */
	u16 devno;	  /* device number */
	u8 path_mask;
	u8 fla_valid_mask;
	u16 sch;	  /* subchannel */
	u8 chpid[8];	  /* chpids 0-7 */
	u16 fla[8];	  /* full link addresses 0-7 */
} __attribute__ ((packed));

int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd)
{
	struct chsc_ssd_area *ssd_area;
	int ccode;
	int ret;
	int i;
	int mask;

	spin_lock_irq(&chsc_page_lock);
	memset(chsc_page, 0, PAGE_SIZE);
	ssd_area = chsc_page;
	ssd_area->request.length = 0x0010;
	ssd_area->request.code = 0x0004;
	ssd_area->ssid = schid.ssid;
	ssd_area->f_sch = schid.sch_no;
	ssd_area->l_sch = schid.sch_no;

	ccode = chsc(ssd_area);
	/* Check response. */
	if (ccode > 0) {
		ret = (ccode == 3) ? -ENODEV : -EBUSY;
		goto out;
	}
	ret = chsc_error_from_response(ssd_area->response.code);
	if (ret != 0) {
		CIO_MSG_EVENT(2, "chsc: ssd failed for 0.%x.%04x (rc=%04x)\n",
			      schid.ssid, schid.sch_no,
			      ssd_area->response.code);
		goto out;
	}
	if (!ssd_area->sch_valid) {
		ret = -ENODEV;
		goto out;
	}
	/* Copy data */
	ret = 0;
	memset(ssd, 0, sizeof(struct chsc_ssd_info));
	if ((ssd_area->st != SUBCHANNEL_TYPE_IO) &&
	    (ssd_area->st != SUBCHANNEL_TYPE_MSG))
		goto out;
	ssd->path_mask = ssd_area->path_mask;
	ssd->fla_valid_mask = ssd_area->fla_valid_mask;
	for (i = 0; i < 8; i++) {
		mask = 0x80 >> i;
		if (ssd_area->path_mask & mask) {
			chp_id_init(&ssd->chpid[i]);
			ssd->chpid[i].id = ssd_area->chpid[i];
		}
		if (ssd_area->fla_valid_mask & mask)
			ssd->fla[i] = ssd_area->fla[i];
	}
out:
	spin_unlock_irq(&chsc_page_lock);
	return ret;
}

static int s390_subchannel_remove_chpid(struct subchannel *sch, void *data)
{
	spin_lock_irq(sch->lock);
	if (sch->driver && sch->driver->chp_event)
		if