cmf.c
// SPDX-License-Identifier: GPL-2.0+
/*
* Linux on zSeries Channel Measurement Facility support
*
* Copyright IBM Corp. 2000, 2006
*
* Authors: Arnd Bergmann <arndb@de.ibm.com>
* Cornelia Huck <cornelia.huck@de.ibm.com>
*
* original idea from Natarajan Krishnaswami <nkrishna@us.ibm.com>
*/
#define KMSG_COMPONENT "cio"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/bootmem.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/export.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/timex.h> /* get_tod_clock() */
#include <asm/ccwdev.h>
#include <asm/cio.h>
#include <asm/cmb.h>
#include <asm/div64.h>
#include "cio.h"
#include "css.h"
#include "device.h"
#include "ioasm.h"
#include "chsc.h"
/*
* parameter to enable cmf during boot, possible uses are:
* "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be
* used on any subchannel
* "s390cmf=<num>" -- enable cmf and allocate enough memory to measure
* <num> subchannel, where <num> is an integer
* between 1 and 65535, default is 1024
*/
#define ARGSTRING "s390cmf"
/* indices for READCMB */
enum cmb_index {
avg_utilization = -1,
/* basic and exended format: */
cmb_ssch_rsch_count = 0,
cmb_sample_count,
cmb_device_connect_time,
cmb_function_pending_time,
cmb_device_disconnect_time,
cmb_control_unit_queuing_time,
cmb_device_active_only_time,
/* extended format only: */
cmb_device_busy_time,
cmb_initial_command_response_time,
};
/**
* enum cmb_format - types of supported measurement block formats
*
* @CMF_BASIC: traditional channel measurement blocks supported
* by all machines that we run on
* @CMF_EXTENDED: improved format that was introduced with the z990
* machine
* @CMF_AUTODETECT: default: use extended format when running on a machine
* supporting extended format, otherwise fall back to
* basic format
*/
enum cmb_format {
CMF_BASIC,
CMF_EXTENDED,
CMF_AUTODETECT = -1,
};
/*
* format - actual format for all measurement blocks
*
* The format module parameter can be set to a value of 0 (zero)
* or 1, indicating basic or extended format as described for
* enum cmb_format.
*/
static int format = CMF_AUTODETECT;
module_param(format, bint, 0444);
/**
* struct cmb_operations - functions to use depending on cmb_format
*
* Most of these functions operate on a struct ccw_device. There is only
* one instance of struct cmb_operations because the format of the measurement
* data is guaranteed to be the same for every ccw_device.
*
* @alloc: allocate memory for a channel measurement block,
* either with the help of a special pool or with kmalloc
* @free: free memory allocated with @alloc
* @set: enable or disable measurement
* @read: read a measurement entry at an index
* @readall: read a measurement block in a common format
* @reset: clear the data in the associated measurement block and
* reset its time stamp
*/
struct cmb_operations {
int (*alloc) (struct ccw_device *);
void (*free) (struct ccw_device *);
int (*set) (struct ccw_device *, u32);
u64 (*read) (struct ccw_device *, int);
int (*readall)(struct ccw_device *, struct cmbdata *);
void (*reset) (struct ccw_device *);
/* private: */
struct attribute_group *attr_group;
};
static struct cmb_operations *cmbops;
struct cmb_data {
void *hw_block; /* Pointer to block updated by hardware */
void *last_block; /* Last changed block copied from hardware block */
int size; /* Size of hw_block and last_block */
unsigned long long last_update; /* when last_block was updated */
};
/*
* Our user interface is designed in terms of nanoseconds,
* while the hardware measures total times in its own
* unit.
*/
static inline u64 time_to_nsec(u32 value)
{
return ((u64)value) * 128000ull;
}
/*
* Users are usually interested in average times,
* not accumulated time.
* This also helps us with atomicity problems
* when reading sinlge values.
*/
static inline u64 time_to_avg_nsec(u32 value, u32 count)
{
u64 ret;
/* no samples yet, avoid division by 0 */
if (count == 0)
return 0;
/* value comes in units of 128 µsec */
ret = time_to_nsec(value);
do_div(ret, count);
return ret;
}
#define CMF_OFF 0
#define CMF_ON 2
/*
* Activate or deactivate the channel monitor. When area is NULL,
* the monitor is deactivated. The channel monitor needs to
* be active in order to measure subchannels, which also need
* to be enabled.
*/
static inline void cmf_activate(void *area, unsigned int onoff)
{
register void * __gpr2 asm("2");
register long __gpr1 asm("1");
__gpr2 = area;
__gpr1 = onoff;
/* activate channel measurement */
asm("schm" : : "d" (__gpr2), "d" (__gpr1) );
}
static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
unsigned long address)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
int ret;
sch->config.mme = mme;
sch->config.mbfc = mbfc;
/* address can be either a block address or a block index */
if (mbfc)
sch->config.mba = address;
else
sch->config.mbi = address;
ret = cio_commit_config(sch);
if (!mme && ret == -ENODEV) {
/*
* The task was to disable measurement block updates but
* the subchannel is already gone. Report success.
*/
ret = 0;
}
return ret;
}
struct set_schib_struct {
u32 mme;
int mbfc;
unsigned long address;
wait_queue_head_t wait;
int ret;
};
#define CMF_PENDING 1
#define SET_SCHIB_TIMEOUT (10 * HZ)
static int set_schib_wait(struct ccw_device *cdev, u32 mme,
int mbfc, unsigned long address)
{
struct set_schib_struct set_data;
int ret = -ENODEV;
spin_lock_irq(cdev->ccwlock);
if (!cdev->private->cmb)
goto out;
ret = set_schib(cdev, mme, mbfc, address);
if (ret != -EBUSY)
goto out;
/* if the device is not online, don't even try again */
if (cdev->private->state != DEV_STATE_ONLINE)
goto out;
init_waitqueue_head(&set_data.wait);
set_data.mme = mme;
set_data.mbfc = mbfc;
set_data.address = address;
set_data.ret = CMF_PENDING;
cdev->private->state = DEV_STATE_CMFCHANGE;
cdev->private->cmb_wait = &set_data;
spin_unlock_irq(cdev->ccwlock);
ret = wait_event_interruptible_timeout(set_data.wait,
set_data.ret != CMF_PENDING,
SET_SCHIB_TIMEOUT);
spin_lock_irq(cdev->ccwlock);
if (ret <= 0) {
if (set_data.ret == CMF_PENDING) {
set_data.ret = (ret == 0) ? -ETIME : ret;
if (cdev->private->state == DEV_STATE_CMFCHANGE)
cdev->private->state = DEV_STATE_ONLINE;
}
}
cdev->private->cmb_wait = NULL;
ret = set_data.ret;
out:
spin_unlock_irq(cdev->ccwlock);
return ret;
}
void retry_set_schib(struct ccw_device *cdev)
{
struct set_schib_struct *set_data = cdev->private->cmb_wait;
if (!set_data)
return;
set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
set_data->address);
wake_up(&set_data->wait);
}
static int cmf_copy_block(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct cmb_data *cmb_data;
void *hw_block;
if (cio_update_schib(sch))
return -ENODEV;
if (scsw_fctl(&sch->schib.scsw) & SCSW_FCTL_START_FUNC) {
/* Don't copy if a start function is in progress. */
if ((!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_SUSPENDED)) &&
(scsw_actl(&sch->schib.scsw) &
(SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&
(!(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_SEC_STATUS)))
return -EBUSY;
}
cmb_data = cdev->private->cmb;
hw_block = cmb_data->hw_block;
memcpy(cmb_data->last_block, hw_block, cmb_data->size);
cmb_data->last_update = get_tod_clock();
return 0;
}
struct copy_block_struct {
wait_queue_head_t wait;
int ret;
};
static int cmf_cmb_copy_wait(struct ccw_device *cdev)
{
struct copy_block_struct copy_block;
int ret = -ENODEV;
spin_lock_irq(cdev->ccwlock);
if (!cdev->private->cmb)
goto out;
ret = cmf_copy_block(cdev);
if (ret != -EBUSY)
goto out;
if (cdev->private->state != DEV_STATE_ONLINE)
goto out;
init_waitqueue_head(©_block.wait);
copy_block.ret = CMF_PENDING;
cdev->private->state = DEV_STATE_CMFUPDATE;
cdev->private->cmb_wait = ©_block;
spin_unlock_irq(cdev->ccwlock);
ret = wait_event_interruptible(copy_block.wait,
copy_block.ret != CMF_PENDING);
spin_lock_irq(cdev->ccwlock);
if (ret) {
if (copy_block.ret == CMF_PENDING) {
copy_block.ret = -ERESTARTSYS;
if (cdev->private->state == DEV_STATE_CMFUPDATE)
cdev->private->state = DEV_STATE_ONLINE;
}
}
cdev->private->cmb_wait = NULL;
ret = copy_block.ret;
out:
spin_unlock_irq(cdev->ccwlock);
return ret;
}
void cmf_retry_copy_block(struct ccw_device *cdev)
{
struct copy_block_struct *copy_block = cdev->private->cmb_wait;
if (!copy_block)
return;
copy_block->ret = cmf_copy_block(cdev);
wake_up(©_block->wait);
}
static void cmf_generic_reset(struct ccw_device *cdev)
{
struct cmb_data *cmb_data;
spin_lock_irq(cdev->ccwlock);
cmb_data = cdev->private->cmb;
if (cmb_data) {
memset(cmb_data->last_block, 0, cmb_data->size);
/*
* Need to reset hw block as well to make the hardware start
* from 0 again.
*/
memset(cmb_data->hw_block, 0, cmb_data->size);
cmb_data->last_update = 0;
}
cdev->private->cmb_start_time = get_tod_clock();
spin_unlock_irq(cdev->ccwlock);
}
/**
* struct cmb_area - container for global cmb data
*
* @mem: pointer to CMBs (only in basic measurement mode)
* @list: contains a linked list of all subchannels
* @num_channels: number of channels to be measured
* @lock: protect concurrent access to @mem and @list
*/
struct cmb_area {
struct cmb *mem;
struct list_head list;
int num_channels;
spinlock_t lock;
};
static struct cmb_area cmb_area = {
.lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),
.list = LIST_HEAD_INIT(cmb_area.list),
.num_channels = 1024,
};
/* ****** old style CMB handling ********/
/*
* Basic channel measurement blocks are allocated in one contiguous
* block of memory, which can not be moved as long as any channel
* is active. Therefore, a maximum number of subchannels needs to
* be defined somewhere. This is a module parameter, defaulting to
* a reasonable value of 1024, or 32 kb of memory.
* Current kernels don't allow kmalloc with more than 128kb, so the
* maximum is 4096.
*/
module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);
/**
* struct cmb - basic channel measurement block
* @ssch_rsch_count: number of ssch and rsch
* @sample_count: number of samples
* @device_connect_time: time of device connect
* @function_pending_time: time of function pending
* @device_disconnect_time: time of device disconnect
* @control_unit_queuing_time: time of control unit queuing
* @device_active_only_time: time of device active only
* @reserved: unused in basic measurement mode
*
* The measurement block as used by the hardware. The fields are described
* further in z/Architecture Principles of Operation, chapter 17.
*
* The cmb area made up from these blocks must be a contiguous array and may
* not be reallocated or freed.
* Only one cmb area can be present in the system.
*/
struct cmb {
u16 ssch_rsch_count;
u16 sample_count;
u32 device_connect_time;
u32 function_pending_time;
u32 device_disconnect_time;
u32 control_unit_queuing_time;
u32 device_active_only_time;
u32 reserved[2];
};
/*
* Insert a single device into the cmb_area list.
* Called with cmb_area.lock held from alloc_cmb.
*/
static int alloc_cmb_single(struct ccw_device *cdev,
struct cmb_data *cmb_data)
{
struct cmb *cmb;
struct ccw_device_private *node;
int ret;
spin_lock_irq(cdev->ccwlock);
if (!list_empty(&cdev->private->cmb_list)) {
ret = -EBUSY;
goto out;
}
/*
* Find first unused cmb in cmb_area.mem.
* This is a little tricky: cmb_area.list
* remains sorted by ->cmb->hw_data pointers.
*/
cmb = cmb_area.mem;
list_for_each_entry(node, &cmb_area.list, cmb_list) {
struct cmb_data *data;
data = node->cmb;
if ((struct cmb*)data->hw_block > cmb)
break;
cmb++;
}
if (cmb - cmb_area.mem >= cmb_area.num_channels) {
ret = -ENOMEM;
goto out;
}
/* insert new cmb */
list_add_tail(&cdev->private->cmb_list, &node->cmb_list);
cmb_data->hw_block = cmb;
cdev->private->cmb = cmb_data;
ret = 0;
out:
spin_unlock_irq(cdev->ccwlock);
return ret;
}
static int alloc_cmb(struct ccw_device *cdev)
{
int ret;
struct cmb *mem;
ssize_t size;
struct cmb_data *cmb_data;
/* Allocate private cmb_data. */
cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
if (!cmb_data)
return -ENOMEM;
cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);
if (!cmb_data->last_block) {
kfree(cmb_data);
return -ENOMEM;
}
cmb_data->size = sizeof(struct cmb);
spin_lock(&cmb_area.lock);
if (!cmb_area.mem) {
/* there is no user yet, so we need a new area */
size = sizeof(struct cmb) * cmb_area.num_channels;
WARN_ON(!list_empty(&cmb_area.list));
spin_unlock(&cmb_area.lock);
mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA,
get_order(size));
spin_lock(&cmb_area.lock);
if (cmb_area.mem) {
/* ok, another thread was faster */
free_pages((unsigned long)mem, get_order(size));
} else if (!mem) {
/* no luck */
ret = -ENOMEM;
goto out;
} else {
/* everything ok */
memset(mem, 0, size);
cmb_area.mem = mem;
cmf_activate(cmb_area.mem, CMF_ON);
}
}
/* do the actual allocation */
ret = alloc_cmb_single(cdev, cmb_data);
out:
spin_unlock(&cmb_area.lock);
if (ret) {
kfree(cmb_data->last_block);
kfree(cmb_data);
}
return ret;
}
static void free_cmb(struct ccw_device *cdev)
{
struct ccw_device_private *priv;
struct cmb_data *cmb_data;
spin_lock(&cmb_area.lock);
spin_lock_irq(cdev->ccwlock);
priv = cdev->private;
cmb_data = priv->cmb;
priv->cmb = NULL;
if (cmb_data)
kfree(cmb_data->last_block);
kfree(cmb_data);
list_del_init(&priv->cmb_list);
if (list_empty(&cmb_area.list)) {
ssize_t size;
size = sizeof(struct cmb) * cmb_area.num_channels;
cmf_activate(NULL, CMF_OFF);
free_pages((unsigned long)cmb_area.mem, get_order(size));
cmb_area.mem = NULL;
}
spin_unlock_irq(cdev->ccwlock);
spin_unlock(&cmb_area.lock);
}
static int set_cmb(struct ccw_device *cdev, u32 mme)
{
u16 offset;
struct cmb_data *cmb_data;
unsigned long flags;
spin_lock_irqsave(cdev->ccwlock, flags);
if (!cdev->private->cmb) {
spin_unlock_irqrestore(cdev->ccwlock, flags);
return -EINVAL;
}
cmb_data = cdev->private->cmb;
offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;
spin_unlock_irqrestore(cdev->ccwlock, flags);
return set_schib_wait(cdev, mme, 0, offset);
}
/* calculate utilization in 0.1 percent units */
static u64 __cmb_utilization(u64 device_connect_time, u64 function_pending_time,
u64 device_disconnect_time, u64 start_time)
{
u64 utilization, elapsed_time;
utilization = time_to_nsec(device_connect_time +
function_pending_time +
device_disconnect_time);
elapsed_time = get_tod_clock() - start_time;
elapsed_time = tod_to_ns(elapsed_time);
elapsed_time /= 1000;
return elapsed_time ? (utilization / elapsed_time) : 0;
}
static u64 read_cmb(struct ccw_device *cdev, int index)
{
struct cmb_data *cmb_data;
unsigned long flags;
struct cmb *cmb;
u64 ret = 0;
u32 val;
spin_lock_irqsave(cdev->ccwlock, flags);
cmb_data = cdev->private->cmb;
if (!cmb_data)
goto out;
cmb = cmb_data->hw_block;
switch (index) {
case avg_utilization:
ret = __cmb_utilization(cmb->device_connect_time,
cmb->function_pending_time,
cmb->device_disconnect_time,
cdev->private->cmb_start_time);
goto out;
case cmb_ssch_rsch_count:
ret = cmb->ssch_rsch_count;
goto out;
case cmb_sample_count:
ret = cmb->sample_count;
goto out;
case cmb_device_connect_time:
val = cmb->device_connect_time;
break;
case cmb_function_pending_time:
val = cmb->function_pending_time;
break;
case cmb_device_disconnect_time:
val = cmb->device_disconnect_time;
break;
case cmb_control_unit_queuing_time:
val = cmb->control_unit_queuing_time;
break;
case cmb_device_active_only_time:
val = cmb->device_active_only_time;
break;
default:
goto out;
}
ret = time_to_avg_nsec(val, cmb->sample_count);
out:
spin_unlock_irqrestore(cdev->ccwlock, flags);
return ret;
}
static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)
{
struct cmb *cmb;
struct cmb_data *cmb_data;
u64 time;
unsigned long flags;
int ret;
ret = cmf_cmb_copy_wait(cdev);
if (ret < 0)
return ret;
spin_lock_irqsave(cdev->ccwlock, flags);
cmb_data = cdev->private->cmb;
if (!cmb_data) {
ret = -ENODEV;
goto out;
}
if (cmb_data->last_update == 0) {
ret = -EAGAIN;
goto out;
}
cmb = cmb_data->last_block;
time = cmb_data->last_update - cdev->private->cmb_start_time;
memset(data, 0, sizeof(struct cmbdata));
/* we only know values before device_busy_time */
data->size = offsetof(struct cmbdata, device_busy_time);
data->elapsed_time = tod_to_ns(time);
/* copy data to new structure */
data->ssch_rsch_count = cmb->ssch_rsch_count;
data->sample_count = cmb->sample_count;
/* time fields are converted to nanoseconds while copying */
data->device_connect_time = time_to_nsec(cmb->device_connect_time);
data->function_pending_time = time_to_nsec(cmb->function_pending_time);
data->device_disconnect_time =
time_to_nsec(cmb->device_disconnect_time);
data->control_unit_queuing_time
= time_to_nsec(cmb->control_unit_queuing_time);
data->device_active_only_time
= time_to_nsec(cmb->device_active_only_time);
ret = 0;
out:
spin_unlock_irqrestore(cdev->ccwlock, flags);
return ret;
}
static void reset_cmb(struct ccw_device *cdev)
{
cmf_generic_reset(cdev);
}
static int cmf_enabled(struct ccw_device *cdev)
{
int enabled;
spin_lock_irq(cdev->ccwlock);
enabled = !!cdev->private->cmb;
spin_unlock_irq(cdev->ccwlock);
return enabled;
}
static struct attribute_group cmf_attr_group;
static struct cmb_operations cmbops_basic = {
.alloc = alloc_cmb,
.free = free_cmb,
.set = set_cmb,
.read = read_cmb,
.readall = readall_cmb,
.reset = reset_cmb,
.attr_group = &cmf_attr_group,
};
/* ******** extended cmb handling ********/
/**
* struct cmbe - extended channel measurement block
* @ssch_rsch_count: number of ssch and rsch
* @sample_count: number of samples
* @device_connect_time: time of device connect
* @function_pending_time: time of function pending
* @device_disconnect_time: time of device disconnect
* @control_unit_queuing_time: time of control unit queuing
* @device_active_only_time: time of device active only
* @device_busy_time: time of device busy
* @initial_command_response_time: initial command response time
* @reserved: unused
*
* The measurement block as used by the hardware. May be in any 64 bit physical
* location.
* The fields are described further in z/Architecture Principles of Operation,
* third edition, chapter 17.
*/
struct cmbe {
u32 ssch_rsch_count;
u32 sample_count;
u32 device_connect_time;
u32 function_pending_time;
u32 device_disconnect_time;
u32 control_unit_queuing_time;
u32 device_active_only_time;
u32 device_busy_time;
u32 initial_command_response_time;
u32 reserved[7];
} __packed __aligned(64);
static struct kmem_cache *cmbe_cache;
static int alloc_cmbe(struct ccw_device *cdev)
{
struct cmb_data *cmb_data;
struct cmbe *cmbe;
int ret = -ENOMEM;
cmbe = kmem_cache_zalloc(cmbe_cache, GFP_KERNEL);
if (!cmbe)
return ret;
cmb_data = kzalloc(sizeof(*cmb_data), GFP_KERNEL);
if (!cmb_data)
goto out_free;
cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
if (!cmb_data->last_block)
goto out_free;
cmb_data->size = sizeof(*cmbe);
cmb_data->hw_block = cmbe;
spin_lock(&cmb_area.lock);
spin_lock_irq(cdev->ccwlock);
if (cdev->private->cmb)
goto out_unlock;
cdev->private->cmb = cmb_data;
/* activate global measurement if this is the first channel */
if (list_empty(&cmb_area.list))
cmf_activate(NULL, CMF_ON);
list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
spin_unlock_irq(cdev->ccwlock);
spin_unlock(&cmb_area.lock);
return 0;
out_unlock:
spin_unlock_irq(cdev->ccwlock);
spin_unlock(&cmb_area.lock);
ret = -EBUSY;
out_free:
if (cmb_data)
kfree(cmb_data->last_block);
kfree(cmb_data);
kmem_cache_free(cmbe_cache, cmbe);
return ret;
}
static void free_cmbe(struct ccw_device *cdev)
{
struct cmb_data *cmb_data;
spin_lock(&cmb_area.lock);
spin_lock_irq(cdev->ccwlock);
cmb_data = cdev->private->cmb;
cdev->private->cmb = NULL;
if (cmb_data) {
kfree(cmb_data->last_block);
kmem_cache_free(cmbe_cache, cmb_data->hw_block);
}
kfree(cmb_data);
/* deactivate global measurement if this is the last channel */
list_del_init(&cdev->private->cmb_list);
if (list_empty(&cmb_area.list))
cmf_activate(NULL, CMF_OFF);
spin_unlock_irq(cdev->ccwlock);
spin_unlock(&cmb_area.lock);
}
static int set_cmbe(struct ccw_device *cdev, u32 mme)
{
unsigned long mba;
struct cmb_data *cmb_data;
unsigned long flags;
spin_lock_irqsave(cdev->ccwlock, flags);
if (!cdev->private->cmb) {
spin_unlock_irqrestore(cdev->ccwlock, flags);
return -EINVAL;
}
cmb_data = cdev->private->cmb;
mba = mme ? (unsigned long) cmb_data->hw_block : 0;
spin_unlock_irqrestore(cdev->ccwlock, flags);
return set_schib_wait(cdev, mme, 1, mba);
}
static u64 read_cmbe(struct ccw_device *cdev, int index)
{
struct cmb_data *cmb_data;
unsigned long flags;
struct cmbe *cmb;
u64 ret = 0;
u32 val;
spin_lock_irqsave(cdev->ccwlock, flags);
cmb_data = cdev->private->cmb;
if (!cmb_data)
goto out;
cmb = cmb_data->hw_block;
switch (index) {
case avg_utilization:
ret = __cmb_utilization(cmb->device_connect_time,
cmb->function_pending_time,
cmb->device_disconnect_time,
cdev->private->cmb_start_time);
goto out;
case cmb_ssch_rsch_count:
ret = cmb->ssch_rsch_count;
goto out;
case cmb_sample_count:
ret = cmb->sample_count;
goto out;
case cmb_device_connect_time:
val = cmb->device_connect_time;
break;
case cmb_function_pending_time:
val = cmb->function_pending_time;
break;
case cmb_device_disconnect_time:
val = cmb->device_disconnect_time;
break;
case cmb_control_unit_queuing_time:
val = cmb->control_unit_queuing_time;
break;
case cmb_device_active_only_time:
val = cmb->device_active_only_time;
break;
case cmb_device_busy_time:
val = cmb->device_busy_time;
break;
case cmb_initial_command_response_time:
val = cmb->initial_command_response_time;
break;
default:
goto out;
}
ret = time_to_avg_nsec(val, cmb->sample_count);
out:
spin_unlock_irqrestore(cdev->ccwlock, flags);
return ret;
}
static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)
{
struct cmbe *cmb;
struct cmb_data *cmb_data;
u64 time;
unsigned long flags;
int ret;
ret = cmf_cmb_copy_wait(cdev);
if (ret < 0)
return ret;
spin_lock_irqsave(cdev->ccwlock, flags);
cmb_data = cdev->private->cmb;
if (!cmb_data) {
ret = -ENODEV;
goto out;
}
if (cmb_data->last_update == 0) {
ret = -EAGAIN;
goto out;
}
time = cmb_data->last_update - cdev->private->cmb_start_time;
memset (data, 0, sizeof(struct cmbdata));
/* we only know values before device_busy_time */
data->size = offsetof(struct cmbdata, device_busy_time);
data->elapsed_time = tod_to_ns(time);
cmb = cmb_data->last_block;
/* copy data to new structure */
data->ssch_rsch_count = cmb->ssch_rsch_count;
data->sample_count = cmb->sample_count;
/* time fields are converted to nanoseconds while copying */
data->device_connect_time = time_to_nsec(cmb->device_connect_time);
data->function_pending_time = time_to_nsec(cmb->function_pending_time);
data->device_disconnect_time =
time_to_nsec(cmb->device_disconnect_time);
data->control_unit_queuing_time
= time_to_nsec(cmb->control_unit_queuing_time);
data->device_active_only_time
= time_to_nsec(cmb->device_active_only_time);
data->device_busy_time = time_to_nsec(cmb->device_busy_time);
data->initial_command_response_time
= time_to_nsec(cmb->initial_command_response_time);
ret = 0;
out:
spin_unlock_irqrestore(cdev->ccwlock, flags);
return ret;
}
static void reset_cmbe(struct ccw_device *cdev)
{
cmf_generic_reset(cdev);
}
static struct attribute_group cmf_attr_group_ext;
static struct cmb_operations cmbops_extended = {
.alloc = alloc_cmbe,
.free = free_cmbe,
.set = set_cmbe,
.read = read_cmbe,
.readall = readall_cmbe,
.reset = reset_cmbe,
.attr_group = &cmf_attr_group_ext,
};
static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
{
return sprintf(buf, "%lld\n",
(unsigned long long) cmf_read(to_ccwdev(dev), idx));
}
static ssize_t cmb_show_avg_sample_interval(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
unsigned long count;
long interval;
count = cmf_read(cdev, cmb_sample_count);
spin_lock_irq(cdev->ccwlock);
if (count) {
interval = get_tod_clock() - cdev->private->cmb_start_time;
interval = tod_to_ns(interval);
interval /= count;
} else
interval = -1;
spin_unlock_irq(cdev->ccwlock);
return sprintf(buf, "%ld\n", interval);
}
static ssize_t cmb_show_avg_utilization(struct device *dev,
struct device_attribute *attr,
char *buf)
{
unsigned long u = cmf_read(to_ccwdev(dev), avg_utilization);
return sprintf(buf, "%02lu.%01lu%%\n", u / 10, u % 10);
}
#define cmf_attr(name) \
static ssize_t show_##name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ return cmb_show_attr((dev), buf, cmb_##name); } \
static DEVICE_ATTR(name, 0444, show_##name, NULL);
#define cmf_attr_avg(name) \
static ssize_t show_avg_##name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ return cmb_show_attr((dev), buf, cmb_##name); } \
static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);
cmf_attr(ssch_rsch_count);
cmf_attr(sample_count);
cmf_attr_avg(device_connect_time);
cmf_attr_avg(function_pending_time);
cmf_attr_avg(device_disconnect_time);
cmf_attr_avg(control_unit_queuing_time);
cmf_attr_avg(device_active_only_time);
cmf_attr_avg(device_busy_time);
cmf_attr_avg(initial_command_response_time);
static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,
NULL);
static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);
static struct attribute *cmf_attributes[] = {
&dev_attr_avg_sample_interval.attr,
&dev_attr_avg_utilization.attr,
&dev_attr_ssch_rsch_count.attr,
&dev_attr_sample_count.attr,
&dev_attr_avg_device_connect_time.attr,
&dev_attr_avg_function_pending_time.attr,
&dev_attr_avg_device_disconnect_time.attr,
&dev_attr_avg_control_unit_queuing_time.attr,
&dev_attr_avg_device_active_only_time.attr,
NULL,
};
static struct attribute_group cmf_attr_group = {
.name = "cmf",
.attrs = cmf_attributes,
};
static struct attribute *cmf_attributes_ext[] = {
&dev_attr_avg_sample_interval.attr,
&dev_attr_avg_utilization.attr,
&dev_attr_ssch_rsch_count.attr,
&dev_attr_sample_count.attr,
&dev_attr_avg_device_connect_time.attr,
&dev_attr_avg_function_pending_time.attr,
&dev_attr_avg_device_disconnect_time.attr,
&dev_attr_avg_control_unit_queuing_time.attr,
&dev_attr_avg_device_active_only_time.attr,
&dev_attr_avg_device_busy_time.attr,
&dev_attr_avg_initial_command_response_time.attr,
NULL,
};
static struct attribute_group cmf_attr_group_ext = {
.name = "cmf",
.attrs = cmf_attributes_ext,
};
static ssize_t cmb_enable_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
return sprintf(buf, "%d\n", cmf_enabled(cdev));
}
static ssize_t cmb_enable_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t c)
{
struct ccw_device *cdev = to_ccwdev(dev);
unsigned long val;
int ret;
ret = kstrtoul(buf, 16, &val);
if (ret)
return ret;
switch (val) {
case 0:
ret = disable_cmf(cdev);
break;
case 1:
ret = enable_cmf(cdev);
break;
default:
ret = -EINVAL;
}
return ret ? ret : c;
}
DEVICE_ATTR_RW(cmb_enable);
int ccw_set_cmf(struct ccw_device *cdev, int enable)
{
return cmbops->set(cdev, enable ? 2 : 0);
}
/**
* enable_cmf() - switch on the channel measurement for a specific device
* @cdev: The ccw device to be enabled
*
* Returns %0 for success or a negative error value.
* Note: If this is called on a device for which channel measurement is already
* enabled a reset of the measurement data is triggered.
* Context:
* non-atomic
*/
int enable_cmf(struct ccw_device *cdev)
{
int ret = 0;
device_lock(&cdev->dev);
if (cmf_enabled(cdev)) {
cmbops->reset(cdev);
goto out_unlock;
}
get_device(&cdev->dev);
ret = cmbops->alloc(cdev);
if (ret)
goto out;
cmbops->reset(cdev);
ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
if (ret) {
cmbops->free(cdev);
goto out;
}
ret = cmbops->set(cdev, 2);
if (ret) {
sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
cmbops->free(cdev);
}
out:
if (ret)
put_device(&cdev->dev);
out_unlock:
device_unlock(&cdev->dev);
return ret;
}
/**
* __disable_cmf() - switch off the channel measurement for a specific device
* @cdev: The ccw device to be disabled
*
* Returns %0 for success or a negative error value.
*
* Context:
* non-atomic, device_lock() held.
*/
int __disable_cmf(struct ccw_device *cdev)
{
int ret;
ret = cmbops->set(cdev, 0);
if (ret)
return ret;
sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
cmbops->free(cdev);
put_device(&cdev->dev);
return ret;
}
/**
* disable_cmf() - switch off the channel measurement for a specific device
* @cdev: The ccw device to be disabled
*
* Returns %0 for success or a negative error value.
*
* Context:
* non-atomic
*/
int disable_cmf(struct ccw_device *cdev)
{
int ret;
device_lock(&cdev->dev);
ret = __disable_cmf(cdev);
device_unlock(&cdev->dev);
return ret;
}
/**
* cmf_read() - read one value from the current channel measurement block
* @cdev: the channel to be read
* @index: the index of the value to be read
*
* Returns the value read or %0 if the value cannot be read.
*
* Context:
* any
*/
u64 cmf_read(struct ccw_device *cdev, int index)
{
return cmbops->read(cdev, index);
}
/**
* cmf_readall() - read the current channel measurement block
* @cdev: the channel to be read
* @data: a pointer to a data block that will be filled
*
* Returns %0 on success, a negative error value otherwise.
*
* Context:
* any
*/
int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
{
return cmbops->readall(cdev, data);
}
/* Reenable cmf when a disconnected device becomes available again. */
int cmf_reenable(struct ccw_device *cdev)
{
cmbops->reset(cdev);
return cmbops->set(cdev, 2);
}
/**
* cmf_reactivate() - reactivate measurement block updates
*
* Use this during resume from hibernate.
*/
void cmf_reactivate(void)
{
spin_lock(&cmb_area.lock);
if (!list_empty(&cmb_area.list))
cmf_activate(cmb_area.mem, CMF_ON);
spin_unlock(&cmb_area.lock);
}
static int __init init_cmbe(void)
{
cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe),
__alignof__(struct cmbe), 0, NULL);
return cmbe_cache ? 0 : -ENOMEM;
}
static int __init init_cmf(void)
{
char *format_string;
char *detect_string;
int ret;
/*
* If the user did not give a parameter, see if we are running on a
* machine supporting extended measurement blocks, otherwise fall back
* to basic mode.
*/
if (format == CMF_AUTODETECT) {
if (!css_general_characteristics.ext_mb) {
format = CMF_BASIC;
} else {
format = CMF_EXTENDED;
}
detect_string = "autodetected";
} else {
detect_string = "parameter";
}
switch (format) {
case CMF_BASIC:
format_string = "basic";
cmbops = &cmbops_basic;
break;
case CMF_EXTENDED:
format_string = "extended";
cmbops = &cmbops_extended;
ret = init_cmbe();
if (ret)
return ret;
break;
default:
return -EINVAL;
}
pr_info("Channel measurement facility initialized using format "
"%s (mode %s)\n", format_string, detect_string);
return 0;
}
device_initcall(init_cmf);
EXPORT_SYMBOL_GPL(enable_cmf);
EXPORT_SYMBOL_GPL(disable_cmf);
EXPORT_SYMBOL_GPL(cmf_read);
EXPORT_SYMBOL_GPL(cmf_readall);