Commit 2dc8903a authored by Peter Oberparleiter's avatar Peter Oberparleiter Committed by Alexander Gordeev
Browse files

s390/cio: export extended channel-path-measurement data 



Add a per-CHPID binary sysfs attribute named "ext_measurement" that
provides access to extended channel-path-measurement data for the
associated channel path.

Note that while not all channel-paths provide extended measurement data
this attribute is created unconditionally for all channel paths because
channel-path measurement capabilities might change during run-time.
Reading from the attribute will only return data for channel-paths that
support extended measurement data.

Example:

$ echo 1 > /sys/devices/css0/cm_enable
$ xxd /sys/devices/css0/chp0.32/ext_measurement
00000000: 53e0 8002 0000 0095 0000 0000 59cc e034  S...........Y..4
00000010: 38b8 cc45 0000 0000 0000 0000 3e24 fe94  8..E........>$..
00000020: 0000 0000 0000 0000 0000 0000 0000 0000  ................
00000030: 0000 0000 0000 0000 0000 0000 0000 0000  ................

Reviewed-by: default avatarVineeth Vijayan <vneethv@linux.ibm.com>
Tested-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 b4691baa

drivers/s390/cio/chp.c

+39 −29
Original line number Diff line number Diff line
@@ -144,55 +144,65 @@ static ssize_t measurement_chars_read(struct file *filp, struct kobject *kobj, 
}

static BIN_ATTR_ADMIN_RO(measurement_chars, sizeof(struct cmg_chars));



static void chp_measurement_copy_block(struct cmg_entry *buf,

				       struct channel_subsystem *css,

				       struct chp_id chpid)

{

	void *area;

	struct cmg_entry *entry, reference_buf;

	int idx;



	if (chpid.id < CSS_CUES_PER_PAGE) {

		area = css->cub[0];

		idx = chpid.id;

	} else {

		area = css->cub[1];

		idx = chpid.id - CSS_CUES_PER_PAGE;

	}

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

	do {

		memcpy(buf, entry, sizeof(*entry));

		memcpy(&reference_buf, entry, sizeof(*entry));

	} while (reference_buf.values[0] != buf->values[0]);

}



static ssize_t measurement_read(struct file *filp, struct kobject *kobj,

				struct bin_attribute *bin_attr,

				char *buf, loff_t off, size_t count)

static ssize_t chp_measurement_copy_block(void *buf, loff_t off, size_t count,

					  struct kobject *kobj, bool extended)

{

	struct channel_path *chp;

	struct channel_subsystem *css;

	struct device *device;

	unsigned int size;

	void *area, *entry;

	int id, idx;



	device = kobj_to_dev(kobj);

	chp = to_channelpath(device);

	css = to_css(chp->dev.parent);

	id = chp->chpid.id;



	if (extended) {

		/* Check if extended measurement data is available. */

		if (!chp->extended)

			return 0;



		size = sizeof(struct cmg_ext_entry);

		area = css->ecub[id / CSS_ECUES_PER_PAGE];

		idx = id % CSS_ECUES_PER_PAGE;

	} else {

		size = sizeof(struct cmg_entry);

		area = css->cub[id / CSS_CUES_PER_PAGE];

		idx = id % CSS_CUES_PER_PAGE;

	}

	entry = area + (idx * size);



	/* Only allow single reads. */

	if (off || count < size)

		return 0;

	chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);

	count = size;

	return count;



	memcpy(buf, entry, size);



	return size;

}



static ssize_t measurement_read(struct file *filp, struct kobject *kobj,

				struct bin_attribute *bin_attr,

				char *buf, loff_t off, size_t count)

{

	return chp_measurement_copy_block(buf, off, count, kobj, false);

}

static BIN_ATTR_ADMIN_RO(measurement, sizeof(struct cmg_entry));



static ssize_t ext_measurement_read(struct file *filp, struct kobject *kobj,

				    struct bin_attribute *bin_attr,

				    char *buf, loff_t off, size_t count)

{

	return chp_measurement_copy_block(buf, off, count, kobj, true);

}

static BIN_ATTR_ADMIN_RO(ext_measurement, sizeof(struct cmg_ext_entry));



static struct bin_attribute *measurement_attrs[] = {

	&bin_attr_measurement_chars,

	&bin_attr_measurement,

	&bin_attr_ext_measurement,

	NULL,

};

BIN_ATTRIBUTE_GROUPS(measurement);

drivers/s390/cio/chp.h

+1 −0
Original line number Diff line number Diff line
@@ -51,6 +51,7 @@ struct channel_path { 
	/* Channel-measurement related stuff: */

	int cmg;

	int shared;

	int extended;

	struct cmg_chars cmg_chars;

};

drivers/s390/cio/chsc.c

+21 −3
Original line number Diff line number Diff line
@@ -871,11 +871,14 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) 
	struct {

		struct chsc_header request;

		u32 operation_code : 2;

		u32 : 30;

		u32 : 1;

		u32 e : 1;

		u32 : 28;

		u32 key : 4;

		u32 : 28;

		dma64_t cub[CSS_NUM_CUB_PAGES];

		u32 reserved[13];

		dma64_t ecub[CSS_NUM_ECUB_PAGES];

		u32 reserved[5];

		struct chsc_header response;

		u32 status : 8;

		u32 : 4;
@@ -892,9 +895,12 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) 
	secm_area->request.code = 0x0016;



	secm_area->key = PAGE_DEFAULT_KEY >> 4;

	secm_area->e = 1;



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

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

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

		secm_area->ecub[i] = virt_to_dma64(css->ecub[i]);



	secm_area->operation_code = enable ? 0 : 1;
@@ -929,6 +935,11 @@ static int cub_alloc(struct channel_subsystem *css) 
		if (!css->cub[i])

			return -ENOMEM;

	}

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

		css->ecub[i] = (void *)get_zeroed_page(GFP_KERNEL);

		if (!css->ecub[i])

			return -ENOMEM;

	}



	return 0;

}
@@ -941,6 +952,10 @@ static void cub_free(struct channel_subsystem *css) 
		free_page((unsigned long)css->cub[i]);

		css->cub[i] = NULL;

	}

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

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

		css->ecub[i] = NULL;

	}

}



int
@@ -1067,7 +1082,8 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp) 
		u32 zeroes2;

		u32 not_valid : 1;

		u32 shared : 1;

		u32 : 22;

		u32 extended : 1;

		u32 : 21;

		u32 chpid : 8;

		u32 cmcv : 5;

		u32 : 11;
@@ -1079,6 +1095,7 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp) 


	chp->shared = -1;

	chp->cmg = -1;

	chp->extended = 0;



	if (!css_chsc_characteristics.scmc || !css_chsc_characteristics.secm)

		return -EINVAL;
@@ -1108,6 +1125,7 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp) 


	chp->cmg = scmc_area->cmg;

	chp->shared = scmc_area->shared;

	chp->extended = scmc_area->extended;

	if (chp->cmg != 2 && chp->cmg != 3) {

		/* No cmg-dependent data. */

		goto out;

drivers/s390/cio/chsc.h

+5 −0
Original line number Diff line number Diff line
@@ -22,6 +22,11 @@ struct cmg_entry { 
	u32 values[NR_MEASUREMENT_ENTRIES];

};



#define NR_EXT_MEASUREMENT_ENTRIES 16

struct cmg_ext_entry {

	u32 values[NR_EXT_MEASUREMENT_ENTRIES];

};



struct channel_path_desc_fmt1 {

	u8 flags;

	u8 lsn;

drivers/s390/cio/css.h

+3 −0
Original line number Diff line number Diff line
@@ -40,6 +40,8 @@ 


#define CSS_NUM_CUB_PAGES		2

#define CSS_CUES_PER_PAGE		128

#define CSS_NUM_ECUB_PAGES		4

#define CSS_ECUES_PER_PAGE		64



/*

 * Conditions used to specify which subchannels need evaluation
@@ -130,6 +132,7 @@ struct channel_subsystem { 
	/* channel measurement related */

	int cm_enabled;

	void *cub[CSS_NUM_CUB_PAGES];

	void *ecub[CSS_NUM_ECUB_PAGES];

	/* for orphaned ccw devices */

	struct subchannel *pseudo_subchannel;

};