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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Linux on zSeries Channel Measurement Facility support4 *5 * Copyright IBM Corp. 2000, 20066 *7 * Authors: Arnd Bergmann <arndb@de.ibm.com>8 *	    Cornelia Huck <cornelia.huck@de.ibm.com>9 *10 * original idea from Natarajan Krishnaswami <nkrishna@us.ibm.com>11 */12 13#define KMSG_COMPONENT "cio"14#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt15 16#include <linux/memblock.h>17#include <linux/device.h>18#include <linux/init.h>19#include <linux/list.h>20#include <linux/export.h>21#include <linux/moduleparam.h>22#include <linux/slab.h>23#include <linux/timex.h>	/* get_tod_clock() */24 25#include <asm/ccwdev.h>26#include <asm/cio.h>27#include <asm/cmb.h>28#include <asm/div64.h>29 30#include "cio.h"31#include "css.h"32#include "device.h"33#include "ioasm.h"34#include "chsc.h"35 36/*37 * parameter to enable cmf during boot, possible uses are:38 *  "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be39 *               used on any subchannel40 *  "s390cmf=<num>" -- enable cmf and allocate enough memory to measure41 *                     <num> subchannel, where <num> is an integer42 *                     between 1 and 65535, default is 102443 */44#define ARGSTRING "s390cmf"45 46/* indices for READCMB */47enum cmb_index {48	avg_utilization = -1,49 /* basic and exended format: */50	cmb_ssch_rsch_count = 0,51	cmb_sample_count,52	cmb_device_connect_time,53	cmb_function_pending_time,54	cmb_device_disconnect_time,55	cmb_control_unit_queuing_time,56	cmb_device_active_only_time,57 /* extended format only: */58	cmb_device_busy_time,59	cmb_initial_command_response_time,60};61 62/**63 * enum cmb_format - types of supported measurement block formats64 *65 * @CMF_BASIC:      traditional channel measurement blocks supported66 *		    by all machines that we run on67 * @CMF_EXTENDED:   improved format that was introduced with the z99068 *		    machine69 * @CMF_AUTODETECT: default: use extended format when running on a machine70 *		    supporting extended format, otherwise fall back to71 *		    basic format72 */73enum cmb_format {74	CMF_BASIC,75	CMF_EXTENDED,76	CMF_AUTODETECT = -1,77};78 79/*80 * format - actual format for all measurement blocks81 *82 * The format module parameter can be set to a value of 0 (zero)83 * or 1, indicating basic or extended format as described for84 * enum cmb_format.85 */86static int format = CMF_AUTODETECT;87module_param(format, bint, 0444);88 89/**90 * struct cmb_operations - functions to use depending on cmb_format91 *92 * Most of these functions operate on a struct ccw_device. There is only93 * one instance of struct cmb_operations because the format of the measurement94 * data is guaranteed to be the same for every ccw_device.95 *96 * @alloc:	allocate memory for a channel measurement block,97 *		either with the help of a special pool or with kmalloc98 * @free:	free memory allocated with @alloc99 * @set:	enable or disable measurement100 * @read:	read a measurement entry at an index101 * @readall:	read a measurement block in a common format102 * @reset:	clear the data in the associated measurement block and103 *		reset its time stamp104 */105struct cmb_operations {106	int  (*alloc)  (struct ccw_device *);107	void (*free)   (struct ccw_device *);108	int  (*set)    (struct ccw_device *, u32);109	u64  (*read)   (struct ccw_device *, int);110	int  (*readall)(struct ccw_device *, struct cmbdata *);111	void (*reset)  (struct ccw_device *);112/* private: */113	struct attribute_group *attr_group;114};115static struct cmb_operations *cmbops;116 117struct cmb_data {118	void *hw_block;   /* Pointer to block updated by hardware */119	void *last_block; /* Last changed block copied from hardware block */120	int size;	  /* Size of hw_block and last_block */121	unsigned long long last_update;  /* when last_block was updated */122};123 124/*125 * Our user interface is designed in terms of nanoseconds,126 * while the hardware measures total times in its own127 * unit.128 */129static inline u64 time_to_nsec(u32 value)130{131	return ((u64)value) * 128000ull;132}133 134/*135 * Users are usually interested in average times,136 * not accumulated time.137 * This also helps us with atomicity problems138 * when reading sinlge values.139 */140static inline u64 time_to_avg_nsec(u32 value, u32 count)141{142	u64 ret;143 144	/* no samples yet, avoid division by 0 */145	if (count == 0)146		return 0;147 148	/* value comes in units of 128 µsec */149	ret = time_to_nsec(value);150	do_div(ret, count);151 152	return ret;153}154 155#define CMF_OFF 0156#define CMF_ON	2157 158/*159 * Activate or deactivate the channel monitor. When area is NULL,160 * the monitor is deactivated. The channel monitor needs to161 * be active in order to measure subchannels, which also need162 * to be enabled.163 */164static inline void cmf_activate(void *area, unsigned int onoff)165{166	/* activate channel measurement */167	asm volatile(168		"	lgr	1,%[r1]\n"169		"	lgr	2,%[mbo]\n"170		"	schm\n"171		:172		: [r1] "d" ((unsigned long)onoff),173		  [mbo] "d" (virt_to_phys(area))174		: "1", "2");175}176 177static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,178		     unsigned long address)179{180	struct subchannel *sch = to_subchannel(cdev->dev.parent);181	int ret;182 183	sch->config.mme = mme;184	sch->config.mbfc = mbfc;185	/* address can be either a block address or a block index */186	if (mbfc)187		sch->config.mba = address;188	else189		sch->config.mbi = address;190 191	ret = cio_commit_config(sch);192	if (!mme && ret == -ENODEV) {193		/*194		 * The task was to disable measurement block updates but195		 * the subchannel is already gone. Report success.196		 */197		ret = 0;198	}199	return ret;200}201 202struct set_schib_struct {203	u32 mme;204	int mbfc;205	unsigned long address;206	wait_queue_head_t wait;207	int ret;208};209 210#define CMF_PENDING 1211#define SET_SCHIB_TIMEOUT (10 * HZ)212 213static int set_schib_wait(struct ccw_device *cdev, u32 mme,214			  int mbfc, unsigned long address)215{216	struct set_schib_struct set_data;217	int ret = -ENODEV;218 219	spin_lock_irq(cdev->ccwlock);220	if (!cdev->private->cmb)221		goto out;222 223	ret = set_schib(cdev, mme, mbfc, address);224	if (ret != -EBUSY)225		goto out;226 227	/* if the device is not online, don't even try again */228	if (cdev->private->state != DEV_STATE_ONLINE)229		goto out;230 231	init_waitqueue_head(&set_data.wait);232	set_data.mme = mme;233	set_data.mbfc = mbfc;234	set_data.address = address;235	set_data.ret = CMF_PENDING;236 237	cdev->private->state = DEV_STATE_CMFCHANGE;238	cdev->private->cmb_wait = &set_data;239	spin_unlock_irq(cdev->ccwlock);240 241	ret = wait_event_interruptible_timeout(set_data.wait,242					       set_data.ret != CMF_PENDING,243					       SET_SCHIB_TIMEOUT);244	spin_lock_irq(cdev->ccwlock);245	if (ret <= 0) {246		if (set_data.ret == CMF_PENDING) {247			set_data.ret = (ret == 0) ? -ETIME : ret;248			if (cdev->private->state == DEV_STATE_CMFCHANGE)249				cdev->private->state = DEV_STATE_ONLINE;250		}251	}252	cdev->private->cmb_wait = NULL;253	ret = set_data.ret;254out:255	spin_unlock_irq(cdev->ccwlock);256	return ret;257}258 259void retry_set_schib(struct ccw_device *cdev)260{261	struct set_schib_struct *set_data = cdev->private->cmb_wait;262 263	if (!set_data)264		return;265 266	set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,267				  set_data->address);268	wake_up(&set_data->wait);269}270 271static int cmf_copy_block(struct ccw_device *cdev)272{273	struct subchannel *sch = to_subchannel(cdev->dev.parent);274	struct cmb_data *cmb_data;275	void *hw_block;276 277	if (cio_update_schib(sch))278		return -ENODEV;279 280	if (scsw_fctl(&sch->schib.scsw) & SCSW_FCTL_START_FUNC) {281		/* Don't copy if a start function is in progress. */282		if ((!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_SUSPENDED)) &&283		    (scsw_actl(&sch->schib.scsw) &284		     (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&285		    (!(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_SEC_STATUS)))286			return -EBUSY;287	}288	cmb_data = cdev->private->cmb;289	hw_block = cmb_data->hw_block;290	memcpy(cmb_data->last_block, hw_block, cmb_data->size);291	cmb_data->last_update = get_tod_clock();292	return 0;293}294 295struct copy_block_struct {296	wait_queue_head_t wait;297	int ret;298};299 300static int cmf_cmb_copy_wait(struct ccw_device *cdev)301{302	struct copy_block_struct copy_block;303	int ret = -ENODEV;304 305	spin_lock_irq(cdev->ccwlock);306	if (!cdev->private->cmb)307		goto out;308 309	ret = cmf_copy_block(cdev);310	if (ret != -EBUSY)311		goto out;312 313	if (cdev->private->state != DEV_STATE_ONLINE)314		goto out;315 316	init_waitqueue_head(&copy_block.wait);317	copy_block.ret = CMF_PENDING;318 319	cdev->private->state = DEV_STATE_CMFUPDATE;320	cdev->private->cmb_wait = &copy_block;321	spin_unlock_irq(cdev->ccwlock);322 323	ret = wait_event_interruptible(copy_block.wait,324				       copy_block.ret != CMF_PENDING);325	spin_lock_irq(cdev->ccwlock);326	if (ret) {327		if (copy_block.ret == CMF_PENDING) {328			copy_block.ret = -ERESTARTSYS;329			if (cdev->private->state == DEV_STATE_CMFUPDATE)330				cdev->private->state = DEV_STATE_ONLINE;331		}332	}333	cdev->private->cmb_wait = NULL;334	ret = copy_block.ret;335out:336	spin_unlock_irq(cdev->ccwlock);337	return ret;338}339 340void cmf_retry_copy_block(struct ccw_device *cdev)341{342	struct copy_block_struct *copy_block = cdev->private->cmb_wait;343 344	if (!copy_block)345		return;346 347	copy_block->ret = cmf_copy_block(cdev);348	wake_up(&copy_block->wait);349}350 351static void cmf_generic_reset(struct ccw_device *cdev)352{353	struct cmb_data *cmb_data;354 355	spin_lock_irq(cdev->ccwlock);356	cmb_data = cdev->private->cmb;357	if (cmb_data) {358		memset(cmb_data->last_block, 0, cmb_data->size);359		/*360		 * Need to reset hw block as well to make the hardware start361		 * from 0 again.362		 */363		memset(cmb_data->hw_block, 0, cmb_data->size);364		cmb_data->last_update = 0;365	}366	cdev->private->cmb_start_time = get_tod_clock();367	spin_unlock_irq(cdev->ccwlock);368}369 370/**371 * struct cmb_area - container for global cmb data372 *373 * @mem:	pointer to CMBs (only in basic measurement mode)374 * @list:	contains a linked list of all subchannels375 * @num_channels: number of channels to be measured376 * @lock:	protect concurrent access to @mem and @list377 */378struct cmb_area {379	struct cmb *mem;380	struct list_head list;381	int num_channels;382	spinlock_t lock;383};384 385static struct cmb_area cmb_area = {386	.lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),387	.list = LIST_HEAD_INIT(cmb_area.list),388	.num_channels  = 1024,389};390 391/* ****** old style CMB handling ********/392 393/*394 * Basic channel measurement blocks are allocated in one contiguous395 * block of memory, which can not be moved as long as any channel396 * is active. Therefore, a maximum number of subchannels needs to397 * be defined somewhere. This is a module parameter, defaulting to398 * a reasonable value of 1024, or 32 kb of memory.399 * Current kernels don't allow kmalloc with more than 128kb, so the400 * maximum is 4096.401 */402 403module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);404 405/**406 * struct cmb - basic channel measurement block407 * @ssch_rsch_count: number of ssch and rsch408 * @sample_count: number of samples409 * @device_connect_time: time of device connect410 * @function_pending_time: time of function pending411 * @device_disconnect_time: time of device disconnect412 * @control_unit_queuing_time: time of control unit queuing413 * @device_active_only_time: time of device active only414 * @reserved: unused in basic measurement mode415 *416 * The measurement block as used by the hardware. The fields are described417 * further in z/Architecture Principles of Operation, chapter 17.418 *419 * The cmb area made up from these blocks must be a contiguous array and may420 * not be reallocated or freed.421 * Only one cmb area can be present in the system.422 */423struct cmb {424	u16 ssch_rsch_count;425	u16 sample_count;426	u32 device_connect_time;427	u32 function_pending_time;428	u32 device_disconnect_time;429	u32 control_unit_queuing_time;430	u32 device_active_only_time;431	u32 reserved[2];432};433 434/*435 * Insert a single device into the cmb_area list.436 * Called with cmb_area.lock held from alloc_cmb.437 */438static int alloc_cmb_single(struct ccw_device *cdev,439			    struct cmb_data *cmb_data)440{441	struct cmb *cmb;442	struct ccw_device_private *node;443	int ret;444 445	spin_lock_irq(cdev->ccwlock);446	if (!list_empty(&cdev->private->cmb_list)) {447		ret = -EBUSY;448		goto out;449	}450 451	/*452	 * Find first unused cmb in cmb_area.mem.453	 * This is a little tricky: cmb_area.list454	 * remains sorted by ->cmb->hw_data pointers.455	 */456	cmb = cmb_area.mem;457	list_for_each_entry(node, &cmb_area.list, cmb_list) {458		struct cmb_data *data;459		data = node->cmb;460		if ((struct cmb*)data->hw_block > cmb)461			break;462		cmb++;463	}464	if (cmb - cmb_area.mem >= cmb_area.num_channels) {465		ret = -ENOMEM;466		goto out;467	}468 469	/* insert new cmb */470	list_add_tail(&cdev->private->cmb_list, &node->cmb_list);471	cmb_data->hw_block = cmb;472	cdev->private->cmb = cmb_data;473	ret = 0;474out:475	spin_unlock_irq(cdev->ccwlock);476	return ret;477}478 479static int alloc_cmb(struct ccw_device *cdev)480{481	int ret;482	struct cmb *mem;483	ssize_t size;484	struct cmb_data *cmb_data;485 486	/* Allocate private cmb_data. */487	cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);488	if (!cmb_data)489		return -ENOMEM;490 491	cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);492	if (!cmb_data->last_block) {493		kfree(cmb_data);494		return -ENOMEM;495	}496	cmb_data->size = sizeof(struct cmb);497	spin_lock(&cmb_area.lock);498 499	if (!cmb_area.mem) {500		/* there is no user yet, so we need a new area */501		size = sizeof(struct cmb) * cmb_area.num_channels;502		WARN_ON(!list_empty(&cmb_area.list));503 504		spin_unlock(&cmb_area.lock);505		mem = (void *)__get_free_pages(GFP_KERNEL, get_order(size));506		spin_lock(&cmb_area.lock);507 508		if (cmb_area.mem) {509			/* ok, another thread was faster */510			free_pages((unsigned long)mem, get_order(size));511		} else if (!mem) {512			/* no luck */513			ret = -ENOMEM;514			goto out;515		} else {516			/* everything ok */517			memset(mem, 0, size);518			cmb_area.mem = mem;519			cmf_activate(cmb_area.mem, CMF_ON);520		}521	}522 523	/* do the actual allocation */524	ret = alloc_cmb_single(cdev, cmb_data);525out:526	spin_unlock(&cmb_area.lock);527	if (ret) {528		kfree(cmb_data->last_block);529		kfree(cmb_data);530	}531	return ret;532}533 534static void free_cmb(struct ccw_device *cdev)535{536	struct ccw_device_private *priv;537	struct cmb_data *cmb_data;538 539	spin_lock(&cmb_area.lock);540	spin_lock_irq(cdev->ccwlock);541 542	priv = cdev->private;543	cmb_data = priv->cmb;544	priv->cmb = NULL;545	if (cmb_data)546		kfree(cmb_data->last_block);547	kfree(cmb_data);548	list_del_init(&priv->cmb_list);549 550	if (list_empty(&cmb_area.list)) {551		ssize_t size;552		size = sizeof(struct cmb) * cmb_area.num_channels;553		cmf_activate(NULL, CMF_OFF);554		free_pages((unsigned long)cmb_area.mem, get_order(size));555		cmb_area.mem = NULL;556	}557	spin_unlock_irq(cdev->ccwlock);558	spin_unlock(&cmb_area.lock);559}560 561static int set_cmb(struct ccw_device *cdev, u32 mme)562{563	u16 offset;564	struct cmb_data *cmb_data;565	unsigned long flags;566 567	spin_lock_irqsave(cdev->ccwlock, flags);568	if (!cdev->private->cmb) {569		spin_unlock_irqrestore(cdev->ccwlock, flags);570		return -EINVAL;571	}572	cmb_data = cdev->private->cmb;573	offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;574	spin_unlock_irqrestore(cdev->ccwlock, flags);575 576	return set_schib_wait(cdev, mme, 0, offset);577}578 579/* calculate utilization in 0.1 percent units */580static u64 __cmb_utilization(u64 device_connect_time, u64 function_pending_time,581			     u64 device_disconnect_time, u64 start_time)582{583	u64 utilization, elapsed_time;584 585	utilization = time_to_nsec(device_connect_time +586				   function_pending_time +587				   device_disconnect_time);588 589	elapsed_time = get_tod_clock() - start_time;590	elapsed_time = tod_to_ns(elapsed_time);591	elapsed_time /= 1000;592 593	return elapsed_time ? (utilization / elapsed_time) : 0;594}595 596static u64 read_cmb(struct ccw_device *cdev, int index)597{598	struct cmb_data *cmb_data;599	unsigned long flags;600	struct cmb *cmb;601	u64 ret = 0;602	u32 val;603 604	spin_lock_irqsave(cdev->ccwlock, flags);605	cmb_data = cdev->private->cmb;606	if (!cmb_data)607		goto out;608 609	cmb = cmb_data->hw_block;610	switch (index) {611	case avg_utilization:612		ret = __cmb_utilization(cmb->device_connect_time,613					cmb->function_pending_time,614					cmb->device_disconnect_time,615					cdev->private->cmb_start_time);616		goto out;617	case cmb_ssch_rsch_count:618		ret = cmb->ssch_rsch_count;619		goto out;620	case cmb_sample_count:621		ret = cmb->sample_count;622		goto out;623	case cmb_device_connect_time:624		val = cmb->device_connect_time;625		break;626	case cmb_function_pending_time:627		val = cmb->function_pending_time;628		break;629	case cmb_device_disconnect_time:630		val = cmb->device_disconnect_time;631		break;632	case cmb_control_unit_queuing_time:633		val = cmb->control_unit_queuing_time;634		break;635	case cmb_device_active_only_time:636		val = cmb->device_active_only_time;637		break;638	default:639		goto out;640	}641	ret = time_to_avg_nsec(val, cmb->sample_count);642out:643	spin_unlock_irqrestore(cdev->ccwlock, flags);644	return ret;645}646 647static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)648{649	struct cmb *cmb;650	struct cmb_data *cmb_data;651	u64 time;652	unsigned long flags;653	int ret;654 655	ret = cmf_cmb_copy_wait(cdev);656	if (ret < 0)657		return ret;658	spin_lock_irqsave(cdev->ccwlock, flags);659	cmb_data = cdev->private->cmb;660	if (!cmb_data) {661		ret = -ENODEV;662		goto out;663	}664	if (cmb_data->last_update == 0) {665		ret = -EAGAIN;666		goto out;667	}668	cmb = cmb_data->last_block;669	time = cmb_data->last_update - cdev->private->cmb_start_time;670 671	memset(data, 0, sizeof(struct cmbdata));672 673	/* we only know values before device_busy_time */674	data->size = offsetof(struct cmbdata, device_busy_time);675 676	data->elapsed_time = tod_to_ns(time);677 678	/* copy data to new structure */679	data->ssch_rsch_count = cmb->ssch_rsch_count;680	data->sample_count = cmb->sample_count;681 682	/* time fields are converted to nanoseconds while copying */683	data->device_connect_time = time_to_nsec(cmb->device_connect_time);684	data->function_pending_time = time_to_nsec(cmb->function_pending_time);685	data->device_disconnect_time =686		time_to_nsec(cmb->device_disconnect_time);687	data->control_unit_queuing_time688		= time_to_nsec(cmb->control_unit_queuing_time);689	data->device_active_only_time690		= time_to_nsec(cmb->device_active_only_time);691	ret = 0;692out:693	spin_unlock_irqrestore(cdev->ccwlock, flags);694	return ret;695}696 697static void reset_cmb(struct ccw_device *cdev)698{699	cmf_generic_reset(cdev);700}701 702static int cmf_enabled(struct ccw_device *cdev)703{704	int enabled;705 706	spin_lock_irq(cdev->ccwlock);707	enabled = !!cdev->private->cmb;708	spin_unlock_irq(cdev->ccwlock);709 710	return enabled;711}712 713static struct attribute_group cmf_attr_group;714 715static struct cmb_operations cmbops_basic = {716	.alloc	= alloc_cmb,717	.free	= free_cmb,718	.set	= set_cmb,719	.read	= read_cmb,720	.readall    = readall_cmb,721	.reset	    = reset_cmb,722	.attr_group = &cmf_attr_group,723};724 725/* ******** extended cmb handling ********/726 727/**728 * struct cmbe - extended channel measurement block729 * @ssch_rsch_count: number of ssch and rsch730 * @sample_count: number of samples731 * @device_connect_time: time of device connect732 * @function_pending_time: time of function pending733 * @device_disconnect_time: time of device disconnect734 * @control_unit_queuing_time: time of control unit queuing735 * @device_active_only_time: time of device active only736 * @device_busy_time: time of device busy737 * @initial_command_response_time: initial command response time738 * @reserved: unused739 *740 * The measurement block as used by the hardware. May be in any 64 bit physical741 * location.742 * The fields are described further in z/Architecture Principles of Operation,743 * third edition, chapter 17.744 */745struct cmbe {746	u32 ssch_rsch_count;747	u32 sample_count;748	u32 device_connect_time;749	u32 function_pending_time;750	u32 device_disconnect_time;751	u32 control_unit_queuing_time;752	u32 device_active_only_time;753	u32 device_busy_time;754	u32 initial_command_response_time;755	u32 reserved[7];756} __packed __aligned(64);757 758static struct kmem_cache *cmbe_cache;759 760static int alloc_cmbe(struct ccw_device *cdev)761{762	struct cmb_data *cmb_data;763	struct cmbe *cmbe;764	int ret = -ENOMEM;765 766	cmbe = kmem_cache_zalloc(cmbe_cache, GFP_KERNEL);767	if (!cmbe)768		return ret;769 770	cmb_data = kzalloc(sizeof(*cmb_data), GFP_KERNEL);771	if (!cmb_data)772		goto out_free;773 774	cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);775	if (!cmb_data->last_block)776		goto out_free;777 778	cmb_data->size = sizeof(*cmbe);779	cmb_data->hw_block = cmbe;780 781	spin_lock(&cmb_area.lock);782	spin_lock_irq(cdev->ccwlock);783	if (cdev->private->cmb)784		goto out_unlock;785 786	cdev->private->cmb = cmb_data;787 788	/* activate global measurement if this is the first channel */789	if (list_empty(&cmb_area.list))790		cmf_activate(NULL, CMF_ON);791	list_add_tail(&cdev->private->cmb_list, &cmb_area.list);792 793	spin_unlock_irq(cdev->ccwlock);794	spin_unlock(&cmb_area.lock);795	return 0;796 797out_unlock:798	spin_unlock_irq(cdev->ccwlock);799	spin_unlock(&cmb_area.lock);800	ret = -EBUSY;801out_free:802	if (cmb_data)803		kfree(cmb_data->last_block);804	kfree(cmb_data);805	kmem_cache_free(cmbe_cache, cmbe);806 807	return ret;808}809 810static void free_cmbe(struct ccw_device *cdev)811{812	struct cmb_data *cmb_data;813 814	spin_lock(&cmb_area.lock);815	spin_lock_irq(cdev->ccwlock);816	cmb_data = cdev->private->cmb;817	cdev->private->cmb = NULL;818	if (cmb_data) {819		kfree(cmb_data->last_block);820		kmem_cache_free(cmbe_cache, cmb_data->hw_block);821	}822	kfree(cmb_data);823 824	/* deactivate global measurement if this is the last channel */825	list_del_init(&cdev->private->cmb_list);826	if (list_empty(&cmb_area.list))827		cmf_activate(NULL, CMF_OFF);828	spin_unlock_irq(cdev->ccwlock);829	spin_unlock(&cmb_area.lock);830}831 832static int set_cmbe(struct ccw_device *cdev, u32 mme)833{834	unsigned long mba;835	struct cmb_data *cmb_data;836	unsigned long flags;837 838	spin_lock_irqsave(cdev->ccwlock, flags);839	if (!cdev->private->cmb) {840		spin_unlock_irqrestore(cdev->ccwlock, flags);841		return -EINVAL;842	}843	cmb_data = cdev->private->cmb;844	mba = mme ? (unsigned long) cmb_data->hw_block : 0;845	spin_unlock_irqrestore(cdev->ccwlock, flags);846 847	return set_schib_wait(cdev, mme, 1, mba);848}849 850static u64 read_cmbe(struct ccw_device *cdev, int index)851{852	struct cmb_data *cmb_data;853	unsigned long flags;854	struct cmbe *cmb;855	u64 ret = 0;856	u32 val;857 858	spin_lock_irqsave(cdev->ccwlock, flags);859	cmb_data = cdev->private->cmb;860	if (!cmb_data)861		goto out;862 863	cmb = cmb_data->hw_block;864	switch (index) {865	case avg_utilization:866		ret = __cmb_utilization(cmb->device_connect_time,867					cmb->function_pending_time,868					cmb->device_disconnect_time,869					cdev->private->cmb_start_time);870		goto out;871	case cmb_ssch_rsch_count:872		ret = cmb->ssch_rsch_count;873		goto out;874	case cmb_sample_count:875		ret = cmb->sample_count;876		goto out;877	case cmb_device_connect_time:878		val = cmb->device_connect_time;879		break;880	case cmb_function_pending_time:881		val = cmb->function_pending_time;882		break;883	case cmb_device_disconnect_time:884		val = cmb->device_disconnect_time;885		break;886	case cmb_control_unit_queuing_time:887		val = cmb->control_unit_queuing_time;888		break;889	case cmb_device_active_only_time:890		val = cmb->device_active_only_time;891		break;892	case cmb_device_busy_time:893		val = cmb->device_busy_time;894		break;895	case cmb_initial_command_response_time:896		val = cmb->initial_command_response_time;897		break;898	default:899		goto out;900	}901	ret = time_to_avg_nsec(val, cmb->sample_count);902out:903	spin_unlock_irqrestore(cdev->ccwlock, flags);904	return ret;905}906 907static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)908{909	struct cmbe *cmb;910	struct cmb_data *cmb_data;911	u64 time;912	unsigned long flags;913	int ret;914 915	ret = cmf_cmb_copy_wait(cdev);916	if (ret < 0)917		return ret;918	spin_lock_irqsave(cdev->ccwlock, flags);919	cmb_data = cdev->private->cmb;920	if (!cmb_data) {921		ret = -ENODEV;922		goto out;923	}924	if (cmb_data->last_update == 0) {925		ret = -EAGAIN;926		goto out;927	}928	time = cmb_data->last_update - cdev->private->cmb_start_time;929 930	memset (data, 0, sizeof(struct cmbdata));931 932	/* we only know values before device_busy_time */933	data->size = offsetof(struct cmbdata, device_busy_time);934 935	data->elapsed_time = tod_to_ns(time);936 937	cmb = cmb_data->last_block;938	/* copy data to new structure */939	data->ssch_rsch_count = cmb->ssch_rsch_count;940	data->sample_count = cmb->sample_count;941 942	/* time fields are converted to nanoseconds while copying */943	data->device_connect_time = time_to_nsec(cmb->device_connect_time);944	data->function_pending_time = time_to_nsec(cmb->function_pending_time);945	data->device_disconnect_time =946		time_to_nsec(cmb->device_disconnect_time);947	data->control_unit_queuing_time948		= time_to_nsec(cmb->control_unit_queuing_time);949	data->device_active_only_time950		= time_to_nsec(cmb->device_active_only_time);951	data->device_busy_time = time_to_nsec(cmb->device_busy_time);952	data->initial_command_response_time953		= time_to_nsec(cmb->initial_command_response_time);954 955	ret = 0;956out:957	spin_unlock_irqrestore(cdev->ccwlock, flags);958	return ret;959}960 961static void reset_cmbe(struct ccw_device *cdev)962{963	cmf_generic_reset(cdev);964}965 966static struct attribute_group cmf_attr_group_ext;967 968static struct cmb_operations cmbops_extended = {969	.alloc	    = alloc_cmbe,970	.free	    = free_cmbe,971	.set	    = set_cmbe,972	.read	    = read_cmbe,973	.readall    = readall_cmbe,974	.reset	    = reset_cmbe,975	.attr_group = &cmf_attr_group_ext,976};977 978static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)979{980	return sprintf(buf, "%lld\n",981		(unsigned long long) cmf_read(to_ccwdev(dev), idx));982}983 984static ssize_t cmb_show_avg_sample_interval(struct device *dev,985					    struct device_attribute *attr,986					    char *buf)987{988	struct ccw_device *cdev = to_ccwdev(dev);989	unsigned long count;990	long interval;991 992	count = cmf_read(cdev, cmb_sample_count);993	spin_lock_irq(cdev->ccwlock);994	if (count) {995		interval = get_tod_clock() - cdev->private->cmb_start_time;996		interval = tod_to_ns(interval);997		interval /= count;998	} else999		interval = -1;1000	spin_unlock_irq(cdev->ccwlock);1001	return sprintf(buf, "%ld\n", interval);1002}1003 1004static ssize_t cmb_show_avg_utilization(struct device *dev,1005					struct device_attribute *attr,1006					char *buf)1007{1008	unsigned long u = cmf_read(to_ccwdev(dev), avg_utilization);1009 1010	return sprintf(buf, "%02lu.%01lu%%\n", u / 10, u % 10);1011}1012 1013#define cmf_attr(name) \1014static ssize_t show_##name(struct device *dev, \1015			   struct device_attribute *attr, char *buf)	\1016{ return cmb_show_attr((dev), buf, cmb_##name); } \1017static DEVICE_ATTR(name, 0444, show_##name, NULL);1018 1019#define cmf_attr_avg(name) \1020static ssize_t show_avg_##name(struct device *dev, \1021			       struct device_attribute *attr, char *buf) \1022{ return cmb_show_attr((dev), buf, cmb_##name); } \1023static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);1024 1025cmf_attr(ssch_rsch_count);1026cmf_attr(sample_count);1027cmf_attr_avg(device_connect_time);1028cmf_attr_avg(function_pending_time);1029cmf_attr_avg(device_disconnect_time);1030cmf_attr_avg(control_unit_queuing_time);1031cmf_attr_avg(device_active_only_time);1032cmf_attr_avg(device_busy_time);1033cmf_attr_avg(initial_command_response_time);1034 1035static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,1036		   NULL);1037static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);1038 1039static struct attribute *cmf_attributes[] = {1040	&dev_attr_avg_sample_interval.attr,1041	&dev_attr_avg_utilization.attr,1042	&dev_attr_ssch_rsch_count.attr,1043	&dev_attr_sample_count.attr,1044	&dev_attr_avg_device_connect_time.attr,1045	&dev_attr_avg_function_pending_time.attr,1046	&dev_attr_avg_device_disconnect_time.attr,1047	&dev_attr_avg_control_unit_queuing_time.attr,1048	&dev_attr_avg_device_active_only_time.attr,1049	NULL,1050};1051 1052static struct attribute_group cmf_attr_group = {1053	.name  = "cmf",1054	.attrs = cmf_attributes,1055};1056 1057static struct attribute *cmf_attributes_ext[] = {1058	&dev_attr_avg_sample_interval.attr,1059	&dev_attr_avg_utilization.attr,1060	&dev_attr_ssch_rsch_count.attr,1061	&dev_attr_sample_count.attr,1062	&dev_attr_avg_device_connect_time.attr,1063	&dev_attr_avg_function_pending_time.attr,1064	&dev_attr_avg_device_disconnect_time.attr,1065	&dev_attr_avg_control_unit_queuing_time.attr,1066	&dev_attr_avg_device_active_only_time.attr,1067	&dev_attr_avg_device_busy_time.attr,1068	&dev_attr_avg_initial_command_response_time.attr,1069	NULL,1070};1071 1072static struct attribute_group cmf_attr_group_ext = {1073	.name  = "cmf",1074	.attrs = cmf_attributes_ext,1075};1076 1077static ssize_t cmb_enable_show(struct device *dev,1078			       struct device_attribute *attr,1079			       char *buf)1080{1081	struct ccw_device *cdev = to_ccwdev(dev);1082 1083	return sprintf(buf, "%d\n", cmf_enabled(cdev));1084}1085 1086static ssize_t cmb_enable_store(struct device *dev,1087				struct device_attribute *attr, const char *buf,1088				size_t c)1089{1090	struct ccw_device *cdev = to_ccwdev(dev);1091	unsigned long val;1092	int ret;1093 1094	ret = kstrtoul(buf, 16, &val);1095	if (ret)1096		return ret;1097 1098	switch (val) {1099	case 0:1100		ret = disable_cmf(cdev);1101		break;1102	case 1:1103		ret = enable_cmf(cdev);1104		break;1105	default:1106		ret = -EINVAL;1107	}1108 1109	return ret ? ret : c;1110}1111DEVICE_ATTR_RW(cmb_enable);1112 1113/**1114 * enable_cmf() - switch on the channel measurement for a specific device1115 *  @cdev:	The ccw device to be enabled1116 *1117 *  Enable channel measurements for @cdev. If this is called on a device1118 *  for which channel measurement is already enabled a reset of the1119 *  measurement data is triggered.1120 *  Returns: %0 for success or a negative error value.1121 *  Context:1122 *    non-atomic1123 */1124int enable_cmf(struct ccw_device *cdev)1125{1126	int ret = 0;1127 1128	device_lock(&cdev->dev);1129	if (cmf_enabled(cdev)) {1130		cmbops->reset(cdev);1131		goto out_unlock;1132	}1133	get_device(&cdev->dev);1134	ret = cmbops->alloc(cdev);1135	if (ret)1136		goto out;1137	cmbops->reset(cdev);1138	ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);1139	if (ret) {1140		cmbops->free(cdev);1141		goto out;1142	}1143	ret = cmbops->set(cdev, 2);1144	if (ret) {1145		sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);1146		cmbops->free(cdev);1147	}1148out:1149	if (ret)1150		put_device(&cdev->dev);1151out_unlock:1152	device_unlock(&cdev->dev);1153	return ret;1154}1155 1156/**1157 * __disable_cmf() - switch off the channel measurement for a specific device1158 *  @cdev:	The ccw device to be disabled1159 *1160 *  Returns: %0 for success or a negative error value.1161 *1162 *  Context:1163 *    non-atomic, device_lock() held.1164 */1165int __disable_cmf(struct ccw_device *cdev)1166{1167	int ret;1168 1169	ret = cmbops->set(cdev, 0);1170	if (ret)1171		return ret;1172 1173	sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);1174	cmbops->free(cdev);1175	put_device(&cdev->dev);1176 1177	return ret;1178}1179 1180/**1181 * disable_cmf() - switch off the channel measurement for a specific device1182 *  @cdev:	The ccw device to be disabled1183 *1184 *  Returns: %0 for success or a negative error value.1185 *1186 *  Context:1187 *    non-atomic1188 */1189int disable_cmf(struct ccw_device *cdev)1190{1191	int ret;1192 1193	device_lock(&cdev->dev);1194	ret = __disable_cmf(cdev);1195	device_unlock(&cdev->dev);1196 1197	return ret;1198}1199 1200/**1201 * cmf_read() - read one value from the current channel measurement block1202 * @cdev:	the channel to be read1203 * @index:	the index of the value to be read1204 *1205 * Returns: The value read or %0 if the value cannot be read.1206 *1207 *  Context:1208 *    any1209 */1210u64 cmf_read(struct ccw_device *cdev, int index)1211{1212	return cmbops->read(cdev, index);1213}1214 1215/**1216 * cmf_readall() - read the current channel measurement block1217 * @cdev:	the channel to be read1218 * @data:	a pointer to a data block that will be filled1219 *1220 * Returns: %0 on success, a negative error value otherwise.1221 *1222 *  Context:1223 *    any1224 */1225int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)1226{1227	return cmbops->readall(cdev, data);1228}1229 1230/* Reenable cmf when a disconnected device becomes available again. */1231int cmf_reenable(struct ccw_device *cdev)1232{1233	cmbops->reset(cdev);1234	return cmbops->set(cdev, 2);1235}1236 1237/**1238 * cmf_reactivate() - reactivate measurement block updates1239 *1240 * Use this during resume from hibernate.1241 */1242void cmf_reactivate(void)1243{1244	spin_lock(&cmb_area.lock);1245	if (!list_empty(&cmb_area.list))1246		cmf_activate(cmb_area.mem, CMF_ON);1247	spin_unlock(&cmb_area.lock);1248}1249 1250static int __init init_cmbe(void)1251{1252	cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe),1253				       __alignof__(struct cmbe), 0, NULL);1254 1255	return cmbe_cache ? 0 : -ENOMEM;1256}1257 1258static int __init init_cmf(void)1259{1260	char *format_string;1261	char *detect_string;1262	int ret;1263 1264	/*1265	 * If the user did not give a parameter, see if we are running on a1266	 * machine supporting extended measurement blocks, otherwise fall back1267	 * to basic mode.1268	 */1269	if (format == CMF_AUTODETECT) {1270		if (!css_general_characteristics.ext_mb) {1271			format = CMF_BASIC;1272		} else {1273			format = CMF_EXTENDED;1274		}1275		detect_string = "autodetected";1276	} else {1277		detect_string = "parameter";1278	}1279 1280	switch (format) {1281	case CMF_BASIC:1282		format_string = "basic";1283		cmbops = &cmbops_basic;1284		break;1285	case CMF_EXTENDED:1286		format_string = "extended";1287		cmbops = &cmbops_extended;1288 1289		ret = init_cmbe();1290		if (ret)1291			return ret;1292		break;1293	default:1294		return -EINVAL;1295	}1296	pr_info("Channel measurement facility initialized using format "1297		"%s (mode %s)\n", format_string, detect_string);1298	return 0;1299}1300device_initcall(init_cmf);1301 1302EXPORT_SYMBOL_GPL(enable_cmf);1303EXPORT_SYMBOL_GPL(disable_cmf);1304EXPORT_SYMBOL_GPL(cmf_read);1305EXPORT_SYMBOL_GPL(cmf_readall);1306