Commit a817d98d authored by Peter Oberparleiter's avatar Peter Oberparleiter Committed by Alexander Gordeev
Browse files

s390/cio: rework channel-utilization-block handling 



Convert channel-utilization-block (CUB) address variables from separate
named fields to arrays of addresses. Also simplify error handling and
introduce named constants. This is done in preparation of introducing
additional CUBs.

Note: With this change the __packed annotation of secm_area is required
to prevent an alignment hole that would otherwise occur due to the
switch from u32 to dma64_t.

Reviewed-by: default avatarVineeth Vijayan <vneethv@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent d35c34bb

drivers/s390/cio/chp.c

+4 −4
Original line number Diff line number Diff line
@@ -161,12 +161,12 @@ static void chp_measurement_copy_block(struct cmg_entry *buf, 
	struct cmg_entry *entry, reference_buf;

	int idx;



	if (chpid.id < 128) {

		area = css->cub_addr1;

	if (chpid.id < CSS_CUES_PER_PAGE) {

		area = css->cub[0];

		idx = chpid.id;

	} else {

		area = css->cub_addr2;

		idx = chpid.id - 128;

		area = css->cub[1];

		idx = chpid.id - CSS_CUES_PER_PAGE;

	}

	entry = area + (idx * sizeof(struct cmg_entry));

	do {

drivers/s390/cio/chsc.c

+37 −19
Original line number Diff line number Diff line
@@ -874,19 +874,16 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) 
		u32 : 30;

		u32 key : 4;

		u32 : 28;

		u32 zeroes1;

		dma32_t cub_addr1;

		u32 zeroes2;

		dma32_t cub_addr2;

		dma64_t cub[CSS_NUM_CUB_PAGES];

		u32 reserved[13];

		struct chsc_header response;

		u32 status : 8;

		u32 : 4;

		u32 fmt : 4;

		u32 : 16;

	} *secm_area;

	} __packed *secm_area;

	unsigned long flags;

	int ret, ccode;

	int ret, ccode, i;



	spin_lock_irqsave(&chsc_page_lock, flags);

	memset(chsc_page, 0, PAGE_SIZE);
@@ -895,8 +892,9 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) 
	secm_area->request.code = 0x0016;



	secm_area->key = PAGE_DEFAULT_KEY >> 4;

	secm_area->cub_addr1 = virt_to_dma32(css->cub_addr1);

	secm_area->cub_addr2 = virt_to_dma32(css->cub_addr2);



	for (i = 0; i < CSS_NUM_CUB_PAGES; i++)

		secm_area->cub[i] = (__force dma64_t)virt_to_dma32(css->cub[i]);



	secm_area->operation_code = enable ? 0 : 1;
@@ -922,19 +920,38 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) 
	return ret;

}



static int cub_alloc(struct channel_subsystem *css)

{

	int i;



	for (i = 0; i < CSS_NUM_CUB_PAGES; i++) {

		css->cub[i] = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);

		if (!css->cub[i])

			return -ENOMEM;

	}



	return 0;

}



static void cub_free(struct channel_subsystem *css)

{

	int i;



	for (i = 0; i < CSS_NUM_CUB_PAGES; i++) {

		free_page((unsigned long)css->cub[i]);

		css->cub[i] = NULL;

	}

}



int

chsc_secm(struct channel_subsystem *css, int enable)

{

	int ret;



	if (enable && !css->cm_enabled) {

		css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);

		css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);

		if (!css->cub_addr1 || !css->cub_addr2) {

			free_page((unsigned long)css->cub_addr1);

			free_page((unsigned long)css->cub_addr2);

			return -ENOMEM;

		}

		ret = cub_alloc(css);

		if (ret)

			goto out;

	}

	ret = __chsc_do_secm(css, enable);

	if (!ret) {
@@ -948,10 +965,11 @@ chsc_secm(struct channel_subsystem *css, int enable) 
		} else

			chsc_remove_cmg_attr(css);

	}

	if (!css->cm_enabled) {

		free_page((unsigned long)css->cub_addr1);

		free_page((unsigned long)css->cub_addr2);

	}



out:

	if (!css->cm_enabled)

		cub_free(css);



	return ret;

}

drivers/s390/cio/css.h

+8 −2
Original line number Diff line number Diff line
@@ -34,6 +34,13 @@ 
#define SNID_STATE3_MULTI_PATH	   1

#define SNID_STATE3_SINGLE_PATH	   0



/*

 * Miscellaneous constants

 */



#define CSS_NUM_CUB_PAGES		2

#define CSS_CUES_PER_PAGE		128



/*

 * Conditions used to specify which subchannels need evaluation

 */
@@ -122,8 +129,7 @@ struct channel_subsystem { 
	struct mutex mutex;

	/* channel measurement related */

	int cm_enabled;

	void *cub_addr1;

	void *cub_addr2;

	void *cub[CSS_NUM_CUB_PAGES];

	/* for orphaned ccw devices */

	struct subchannel *pseudo_subchannel;

};