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Commit 9d92a7e1 authored by Cornelia Huck's avatar Cornelia Huck Committed by Heiko Carstens
Browse files

[S390] cio: Add chsc subchannel driver. 



This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the machine's I/O configuration
- dynamically change the machine's I/O configuration via
  asynchronous chsc commands

Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
parent 683c5418

Documentation/ioctl-number.txt

+1 −0
Original line number Diff line number Diff line
@@ -117,6 +117,7 @@ Code Seq# Include File Comments 
					<mailto:natalia@nikhefk.nikhef.nl>

'c'	00-7F	linux/comstats.h	conflict!

'c'	00-7F	linux/coda.h		conflict!

'c'	80-9F	asm-s390/chsc.h

'd'	00-FF	linux/char/drm/drm/h	conflict!

'd'	00-DF	linux/video_decoder.h	conflict!

'd'	F0-FF	linux/digi1.h

arch/s390/Kconfig

+16 −0
Original line number Diff line number Diff line
@@ -345,6 +345,22 @@ config QDIO_DEBUG 


	  If unsure, say N.



config CHSC_SCH

	tristate "Support for CHSC subchannels"

	help

	  This driver allows usage of CHSC subchannels. A CHSC subchannel

	  is usually present on LPAR only.

	  The driver creates a device /dev/chsc, which may be used to

	  obtain I/O configuration information about the machine and

	  to issue asynchronous chsc commands (DANGEROUS).

	  You will usually only want to use this interface on a special

	  LPAR designated for system management.



	  To compile this driver as a module, choose M here: the

	  module will be called chsc_sch.



	  If unsure, say N.



comment "Misc"



config IPL

drivers/s390/cio/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -7,5 +7,6 @@ obj-y += airq.o blacklist.o chsc.o cio.o css.o chp.o idset.o isc.o scsw.o \ 
ccw_device-objs += device.o device_fsm.o device_ops.o

ccw_device-objs += device_id.o device_pgid.o device_status.o

obj-y += ccw_device.o cmf.o

obj-$(CONFIG_CHSC_SCH) += chsc_sch.o

obj-$(CONFIG_CCWGROUP) += ccwgroup.o

obj-$(CONFIG_QDIO) += qdio.o

drivers/s390/cio/chp.c

+1 −1
Original line number Diff line number Diff line
@@ -407,7 +407,7 @@ int chp_new(struct chp_id chpid) 
		 chpid.id);



	/* Obtain channel path description and fill it in. */

	ret = chsc_determine_channel_path_description(chpid, &chp->desc);

	ret = chsc_determine_base_channel_path_desc(chpid, &chp->desc);

	if (ret)

		goto out_free;

	if ((chp->desc.flags & 0x80) == 0) {

drivers/s390/cio/chsc.c

+41 −7
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 


#include <asm/cio.h>

#include <asm/chpid.h>

#include <asm/chsc.h>



#include "../s390mach.h"

#include "css.h"
@@ -627,23 +628,33 @@ chsc_secm(struct channel_subsystem *css, int enable) 
	return ret;

}



int chsc_determine_channel_path_description(struct chp_id chpid,

					    struct channel_path_desc *desc)

int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,

				     int c, int m,

				     struct chsc_response_struct *resp)

{

	int ccode, ret;



	struct {

		struct chsc_header request;

		u32 : 24;

		u32 : 2;

		u32 m : 1;

		u32 c : 1;

		u32 fmt : 4;

		u32 cssid : 8;

		u32 : 4;

		u32 rfmt : 4;

		u32 first_chpid : 8;

		u32 : 24;

		u32 last_chpid : 8;

		u32 zeroes1;

		struct chsc_header response;

		u32 zeroes2;

		struct channel_path_desc desc;

		u8 data[PAGE_SIZE - 20];

	} __attribute__ ((packed)) *scpd_area;



	if ((rfmt == 1) && !css_general_characteristics.fcs)

		return -EINVAL;

	if ((rfmt == 2) && !css_general_characteristics.cib)

		return -EINVAL;

	scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);

	if (!scpd_area)

		return -ENOMEM;
@@ -651,8 +662,13 @@ int chsc_determine_channel_path_description(struct chp_id chpid, 
	scpd_area->request.length = 0x0010;

	scpd_area->request.code = 0x0002;



	scpd_area->cssid = chpid.cssid;

	scpd_area->first_chpid = chpid.id;

	scpd_area->last_chpid = chpid.id;

	scpd_area->m = m;

	scpd_area->c = c;

	scpd_area->fmt = fmt;

	scpd_area->rfmt = rfmt;



	ccode = chsc(scpd_area);

	if (ccode > 0) {
@@ -663,8 +679,7 @@ int chsc_determine_channel_path_description(struct chp_id chpid, 
	ret = chsc_error_from_response(scpd_area->response.code);

	if (ret == 0)

		/* Success. */

		memcpy(desc, &scpd_area->desc,

		       sizeof(struct channel_path_desc));

		memcpy(resp, &scpd_area->response, scpd_area->response.length);

	else

		CIO_CRW_EVENT(2, "chsc: scpd failed (rc=%04x)\n",

			      scpd_area->response.code);
@@ -672,6 +687,25 @@ int chsc_determine_channel_path_description(struct chp_id chpid, 
	free_page((unsigned long)scpd_area);

	return ret;

}

EXPORT_SYMBOL_GPL(chsc_determine_channel_path_desc);



int chsc_determine_base_channel_path_desc(struct chp_id chpid,

					  struct channel_path_desc *desc)

{

	struct chsc_response_struct *chsc_resp;

	int ret;



	chsc_resp = kzalloc(sizeof(*chsc_resp), GFP_KERNEL);

	if (!chsc_resp)

		return -ENOMEM;

	ret = chsc_determine_channel_path_desc(chpid, 0, 0, 0, 0, chsc_resp);

	if (ret)

		goto out_free;

	memcpy(desc, &chsc_resp->data, chsc_resp->length);

out_free:

	kfree(chsc_resp);

	return ret;

}



static void

chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,