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-rw-r--r--drivers/s390/cio/cmf.c1349
1 files changed, 1349 insertions, 0 deletions
diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
new file mode 100644
index 00000000000..204ca728e7f
--- /dev/null
+++ b/drivers/s390/cio/cmf.c
@@ -0,0 +1,1349 @@
+/*
+ * linux/drivers/s390/cio/cmf.c
+ *
+ * Linux on zSeries Channel Measurement Facility support
+ *
+ * Copyright 2000,2006 IBM Corporation
+ *
+ * Authors: Arnd Bergmann <arndb@de.ibm.com>
+ * Cornelia Huck <cornelia.huck@de.ibm.com>
+ *
+ * original idea from Natarajan Krishnaswami <nkrishna@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#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/module.h>
+#include <linux/moduleparam.h>
+#include <linux/slab.h>
+#include <linux/timex.h> /* get_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 {
+ /* basic and exended format: */
+ cmb_ssch_rsch_count,
+ 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
+ * @align: align an allocated block so that the hardware can use it
+ */
+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 *);
+ void *(*align) (void *);
+/* 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 ┬Ásec */
+ ret = time_to_nsec(value);
+ do_div(ret, count);
+
+ return ret;
+}
+
+/*
+ * 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 ? 2 : 0;
+ /* 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;
+
+ sch = to_subchannel(cdev->dev.parent);
+
+ 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;
+
+ return cio_commit_config(sch);
+}
+
+struct set_schib_struct {
+ u32 mme;
+ int mbfc;
+ unsigned long address;
+ wait_queue_head_t wait;
+ int ret;
+ struct kref kref;
+};
+
+static void cmf_set_schib_release(struct kref *kref)
+{
+ struct set_schib_struct *set_data;
+
+ set_data = container_of(kref, struct set_schib_struct, kref);
+ kfree(set_data);
+}
+
+#define CMF_PENDING 1
+
+static int set_schib_wait(struct ccw_device *cdev, u32 mme,
+ int mbfc, unsigned long address)
+{
+ struct set_schib_struct *set_data;
+ int ret;
+
+ spin_lock_irq(cdev->ccwlock);
+ if (!cdev->private->cmb) {
+ ret = -ENODEV;
+ goto out;
+ }
+ set_data = kzalloc(sizeof(struct set_schib_struct), GFP_ATOMIC);
+ if (!set_data) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ init_waitqueue_head(&set_data->wait);
+ kref_init(&set_data->kref);
+ set_data->mme = mme;
+ set_data->mbfc = mbfc;
+ set_data->address = address;
+
+ ret = set_schib(cdev, mme, mbfc, address);
+ if (ret != -EBUSY)
+ goto out_put;
+
+ if (cdev->private->state != DEV_STATE_ONLINE) {
+ /* if the device is not online, don't even try again */
+ ret = -EBUSY;
+ goto out_put;
+ }
+
+ cdev->private->state = DEV_STATE_CMFCHANGE;
+ set_data->ret = CMF_PENDING;
+ cdev->private->cmb_wait = set_data;
+
+ spin_unlock_irq(cdev->ccwlock);
+ if (wait_event_interruptible(set_data->wait,
+ set_data->ret != CMF_PENDING)) {
+ spin_lock_irq(cdev->ccwlock);
+ if (set_data->ret == CMF_PENDING) {
+ set_data->ret = -ERESTARTSYS;
+ if (cdev->private->state == DEV_STATE_CMFCHANGE)
+ cdev->private->state = DEV_STATE_ONLINE;
+ }
+ spin_unlock_irq(cdev->ccwlock);
+ }
+ spin_lock_irq(cdev->ccwlock);
+ cdev->private->cmb_wait = NULL;
+ ret = set_data->ret;
+out_put:
+ kref_put(&set_data->kref, cmf_set_schib_release);
+out:
+ spin_unlock_irq(cdev->ccwlock);
+ return ret;
+}
+
+void retry_set_schib(struct ccw_device *cdev)
+{
+ struct set_schib_struct *set_data;
+
+ set_data = cdev->private->cmb_wait;
+ if (!set_data) {
+ WARN_ON(1);
+ return;
+ }
+ kref_get(&set_data->kref);
+ set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
+ set_data->address);
+ wake_up(&set_data->wait);
+ kref_put(&set_data->kref, cmf_set_schib_release);
+}
+
+static int cmf_copy_block(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+ void *reference_buf;
+ void *hw_block;
+ struct cmb_data *cmb_data;
+
+ sch = to_subchannel(cdev->dev.parent);
+
+ 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 = cmbops->align(cmb_data->hw_block);
+ if (!memcmp(cmb_data->last_block, hw_block, cmb_data->size))
+ /* No need to copy. */
+ return 0;
+ reference_buf = kzalloc(cmb_data->size, GFP_ATOMIC);
+ if (!reference_buf)
+ return -ENOMEM;
+ /* Ensure consistency of block copied from hardware. */
+ do {
+ memcpy(cmb_data->last_block, hw_block, cmb_data->size);
+ memcpy(reference_buf, hw_block, cmb_data->size);
+ } while (memcmp(cmb_data->last_block, reference_buf, cmb_data->size));
+ cmb_data->last_update = get_clock();
+ kfree(reference_buf);
+ return 0;
+}
+
+struct copy_block_struct {
+ wait_queue_head_t wait;
+ int ret;
+ struct kref kref;
+};
+
+static void cmf_copy_block_release(struct kref *kref)
+{
+ struct copy_block_struct *copy_block;
+
+ copy_block = container_of(kref, struct copy_block_struct, kref);
+ kfree(copy_block);
+}
+
+static int cmf_cmb_copy_wait(struct ccw_device *cdev)
+{
+ struct copy_block_struct *copy_block;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(cdev->ccwlock, flags);
+ if (!cdev->private->cmb) {
+ ret = -ENODEV;
+ goto out;
+ }
+ copy_block = kzalloc(sizeof(struct copy_block_struct), GFP_ATOMIC);
+ if (!copy_block) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ init_waitqueue_head(&copy_block->wait);
+ kref_init(&copy_block->kref);
+
+ ret = cmf_copy_block(cdev);
+ if (ret != -EBUSY)
+ goto out_put;
+
+ if (cdev->private->state != DEV_STATE_ONLINE) {
+ ret = -EBUSY;
+ goto out_put;
+ }
+
+ cdev->private->state = DEV_STATE_CMFUPDATE;
+ copy_block->ret = CMF_PENDING;
+ cdev->private->cmb_wait = copy_block;
+
+ spin_unlock_irqrestore(cdev->ccwlock, flags);
+ if (wait_event_interruptible(copy_block->wait,
+ copy_block->ret != CMF_PENDING)) {
+ spin_lock_irqsave(cdev->ccwlock, flags);
+ if (copy_block->ret == CMF_PENDING) {
+ copy_block->ret = -ERESTARTSYS;
+ if (cdev->private->state == DEV_STATE_CMFUPDATE)
+ cdev->private->state = DEV_STATE_ONLINE;
+ }
+ spin_unlock_irqrestore(cdev->ccwlock, flags);
+ }
+ spin_lock_irqsave(cdev->ccwlock, flags);
+ cdev->private->cmb_wait = NULL;
+ ret = copy_block->ret;
+out_put:
+ kref_put(&copy_block->kref, cmf_copy_block_release);
+out:
+ spin_unlock_irqrestore(cdev->ccwlock, flags);
+ return ret;
+}
+
+void cmf_retry_copy_block(struct ccw_device *cdev)
+{
+ struct copy_block_struct *copy_block;
+
+ copy_block = cdev->private->cmb_wait;
+ if (!copy_block) {
+ WARN_ON(1);
+ return;
+ }
+ kref_get(&copy_block->kref);
+ copy_block->ret = cmf_copy_block(cdev);
+ wake_up(&copy_block->wait);
+ kref_put(&copy_block->kref, cmf_copy_block_release);
+}
+
+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(cmbops->align(cmb_data->hw_block), 0, cmb_data->size);
+ cmb_data->last_update = 0;
+ }
+ cdev->private->cmb_start_time = get_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, 1);
+ }
+ }
+
+ /* 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;
+
+ if (list_empty(&priv->cmb_list)) {
+ /* already freed */
+ goto out;
+ }
+
+ 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, 0);
+ free_pages((unsigned long)cmb_area.mem, get_order(size));
+ cmb_area.mem = NULL;
+ }
+out:
+ 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);
+}
+
+static u64 read_cmb(struct ccw_device *cdev, int index)
+{
+ struct cmb *cmb;
+ u32 val;
+ int ret;
+ unsigned long flags;
+
+ ret = cmf_cmb_copy_wait(cdev);
+ if (ret < 0)
+ return 0;
+
+ spin_lock_irqsave(cdev->ccwlock, flags);
+ if (!cdev->private->cmb) {
+ ret = 0;
+ goto out;
+ }
+ cmb = ((struct cmb_data *)cdev->private->cmb)->last_block;
+
+ switch (index) {
+ 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:
+ ret = 0;
+ 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);
+
+ /* convert to nanoseconds */
+ data->elapsed_time = (time * 1000) >> 12;
+
+ /* 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 void * align_cmb(void *area)
+{
+ return area;
+}
+
+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,
+ .align = align_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];
+};
+
+/*
+ * kmalloc only guarantees 8 byte alignment, but we need cmbe
+ * pointers to be naturally aligned. Make sure to allocate
+ * enough space for two cmbes.
+ */
+static inline struct cmbe *cmbe_align(struct cmbe *c)
+{
+ unsigned long addr;
+ addr = ((unsigned long)c + sizeof (struct cmbe) - sizeof(long)) &
+ ~(sizeof (struct cmbe) - sizeof(long));
+ return (struct cmbe*)addr;
+}
+
+static int alloc_cmbe(struct ccw_device *cdev)
+{
+ struct cmbe *cmbe;
+ struct cmb_data *cmb_data;
+ int ret;
+
+ cmbe = kzalloc (sizeof (*cmbe) * 2, GFP_KERNEL);
+ if (!cmbe)
+ return -ENOMEM;
+ cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
+ if (!cmb_data) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+ cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
+ if (!cmb_data->last_block) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+ cmb_data->size = sizeof(struct cmbe);
+ spin_lock_irq(cdev->ccwlock);
+ if (cdev->private->cmb) {
+ spin_unlock_irq(cdev->ccwlock);
+ ret = -EBUSY;
+ goto out_free;
+ }
+ cmb_data->hw_block = cmbe;
+ cdev->private->cmb = cmb_data;
+ spin_unlock_irq(cdev->ccwlock);
+
+ /* activate global measurement if this is the first channel */
+ spin_lock(&cmb_area.lock);
+ if (list_empty(&cmb_area.list))
+ cmf_activate(NULL, 1);
+ list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
+ spin_unlock(&cmb_area.lock);
+
+ return 0;
+out_free:
+ if (cmb_data)
+ kfree(cmb_data->last_block);
+ kfree(cmb_data);
+ kfree(cmbe);
+ return ret;
+}
+
+static void free_cmbe(struct ccw_device *cdev)
+{
+ struct cmb_data *cmb_data;
+
+ spin_lock_irq(cdev->ccwlock);
+ cmb_data = cdev->private->cmb;
+ cdev->private->cmb = NULL;
+ if (cmb_data)
+ kfree(cmb_data->last_block);
+ kfree(cmb_data);
+ spin_unlock_irq(cdev->ccwlock);
+
+ /* deactivate global measurement if this is the last channel */
+ spin_lock(&cmb_area.lock);
+ list_del_init(&cdev->private->cmb_list);
+ if (list_empty(&cmb_area.list))
+ cmf_activate(NULL, 0);
+ 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) cmbe_align(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 cmbe *cmb;
+ struct cmb_data *cmb_data;
+ u32 val;
+ int ret;
+ unsigned long flags;
+
+ ret = cmf_cmb_copy_wait(cdev);
+ if (ret < 0)
+ return 0;
+
+ spin_lock_irqsave(cdev->ccwlock, flags);
+ cmb_data = cdev->private->cmb;
+ if (!cmb_data) {
+ ret = 0;
+ goto out;
+ }
+ cmb = cmb_data->last_block;
+
+ switch (index) {
+ 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:
+ ret = 0;
+ 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);
+
+ /* conver to nanoseconds */
+ data->elapsed_time = (time * 1000) >> 12;
+
+ 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 void * align_cmbe(void *area)
+{
+ return cmbe_align(area);
+}
+
+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,
+ .align = align_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;
+ long interval;
+ unsigned long count;
+ struct cmb_data *cmb_data;
+
+ cdev = to_ccwdev(dev);
+ count = cmf_read(cdev, cmb_sample_count);
+ spin_lock_irq(cdev->ccwlock);
+ cmb_data = cdev->private->cmb;
+ if (count) {
+ interval = cmb_data->last_update -
+ cdev->private->cmb_start_time;
+ interval = (interval * 1000) >> 12;
+ 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)
+{
+ struct cmbdata data;
+ u64 utilization;
+ unsigned long t, u;
+ int ret;
+
+ ret = cmf_readall(to_ccwdev(dev), &data);
+ if (ret == -EAGAIN || ret == -ENODEV)
+ /* No data (yet/currently) available to use for calculation. */
+ return sprintf(buf, "n/a\n");
+ else if (ret)
+ return ret;
+
+ utilization = data.device_connect_time +
+ data.function_pending_time +
+ data.device_disconnect_time;
+
+ /* shift to avoid long long division */
+ while (-1ul < (data.elapsed_time | utilization)) {
+ utilization >>= 8;
+ data.elapsed_time >>= 8;
+ }
+
+ /* calculate value in 0.1 percent units */
+ t = (unsigned long) data.elapsed_time / 1000;
+ u = (unsigned long) utilization / t;
+
+ return sprintf(buf, "%02ld.%01ld%%\n", u/ 10, u - (u/ 10) * 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)
+{
+ return sprintf(buf, "%d\n", to_ccwdev(dev)->private->cmb ? 1 : 0);
+}
+
+static ssize_t cmb_enable_store(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t c)
+{
+ struct ccw_device *cdev;
+ int ret;
+ unsigned long val;
+
+ ret = strict_strtoul(buf, 16, &val);
+ if (ret)
+ return ret;
+
+ cdev = to_ccwdev(dev);
+
+ switch (val) {
+ case 0:
+ ret = disable_cmf(cdev);
+ break;
+ case 1:
+ ret = enable_cmf(cdev);
+ break;
+ }
+
+ return c;
+}
+
+DEVICE_ATTR(cmb_enable, 0644, cmb_enable_show, cmb_enable_store);
+
+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.
+ *
+ * Context:
+ * non-atomic
+ */
+int enable_cmf(struct ccw_device *cdev)
+{
+ int ret;
+
+ ret = cmbops->alloc(cdev);
+ cmbops->reset(cdev);
+ if (ret)
+ return ret;
+ ret = cmbops->set(cdev, 2);
+ if (ret) {
+ cmbops->free(cdev);
+ return ret;
+ }
+ ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
+ if (!ret)
+ return 0;
+ cmbops->set(cdev, 0); //FIXME: this can fail
+ cmbops->free(cdev);
+ 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;
+
+ ret = cmbops->set(cdev, 0);
+ if (ret)
+ return ret;
+ cmbops->free(cdev);
+ sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
+ 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);
+}
+
+static int __init init_cmf(void)
+{
+ char *format_string;
+ char *detect_string = "parameter";
+
+ /*
+ * 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;
+ break;
+ default:
+ return 1;
+ }
+ pr_info("Channel measurement facility initialized using format "
+ "%s (mode %s)\n", format_string, detect_string);
+ return 0;
+}
+
+module_init(init_cmf);
+
+
+MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("channel measurement facility base driver\n"
+ "Copyright 2003 IBM Corporation\n");
+
+EXPORT_SYMBOL_GPL(enable_cmf);
+EXPORT_SYMBOL_GPL(disable_cmf);
+EXPORT_SYMBOL_GPL(cmf_read);
+EXPORT_SYMBOL_GPL(cmf_readall);