From 94bb063312d872d9269deb2e5c0c7c6d5b0318e1 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Thu, 29 Jun 2006 15:08:41 +0200 Subject: [S390] rework of channel measurement facility. Fixes for several channel measurement facility bugs: * Blocks copied from the hardware might not be consistent. Solve this by moving the copying into idle state and repeating the copying. * avg_sample_interval changed with every read, even though no new block was available. Solve this by storing a timestamp when the last new block was received. * Several locking issues. * Measurements were not reenabled after a disconnected device became available again. * Remove #defines for ioctls that were never implemented. Signed-off-by: Cornelia Huck Signed-off-by: Martin Schwidefsky --- drivers/s390/cio/cmf.c | 623 +++++++++++++++++++++++++++++++++++-------------- 1 file changed, 447 insertions(+), 176 deletions(-) (limited to 'drivers/s390/cio/cmf.c') diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c index 07ef3f640f4..1c3e8e9012b 100644 --- a/drivers/s390/cio/cmf.c +++ b/drivers/s390/cio/cmf.c @@ -3,9 +3,10 @@ * * Linux on zSeries Channel Measurement Facility support * - * Copyright 2000,2003 IBM Corporation + * Copyright 2000,2006 IBM Corporation * - * Author: Arnd Bergmann + * Authors: Arnd Bergmann + * Cornelia Huck * * original idea from Natarajan Krishnaswami * @@ -96,9 +97,9 @@ module_param(format, bool, 0444); /** * struct cmb_operations - functions to use depending on cmb_format * - * all these functions operate on a struct cmf_device. There is only - * one instance of struct cmb_operations because all cmf_device - * objects are guaranteed to be of the same type. + * 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 @@ -107,6 +108,7 @@ module_param(format, bool, 0444); * @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*); @@ -115,11 +117,19 @@ struct cmb_operations { u64 (*read) (struct ccw_device*, int); int (*readall)(struct ccw_device*, struct cmbdata *); void (*reset) (struct ccw_device*); + void * (*align) (void *); 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.*/ @@ -226,63 +236,229 @@ struct set_schib_struct { 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 s = { - .mme = mme, - .mbfc = mbfc, - .address = address, - .wait = __WAIT_QUEUE_HEAD_INITIALIZER(s.wait), - }; + struct set_schib_struct *set_data; + int ret; spin_lock_irq(cdev->ccwlock); - s.ret = set_schib(cdev, mme, mbfc, address); - if (s.ret != -EBUSY) { - goto out_nowait; + 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) { - s.ret = -EBUSY; /* if the device is not online, don't even try again */ - goto out_nowait; + ret = -EBUSY; + goto out_put; } + cdev->private->state = DEV_STATE_CMFCHANGE; - cdev->private->cmb_wait = &s; - s.ret = 1; + set_data->ret = CMF_PENDING; + cdev->private->cmb_wait = set_data; spin_unlock_irq(cdev->ccwlock); - if (wait_event_interruptible(s.wait, s.ret != 1)) { + if (wait_event_interruptible(set_data->wait, + set_data->ret != CMF_PENDING)) { spin_lock_irq(cdev->ccwlock); - if (s.ret == 1) { - s.ret = -ERESTARTSYS; - cdev->private->cmb_wait = 0; + 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); } - return s.ret; - -out_nowait: + 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 s.ret; + return ret; } void retry_set_schib(struct ccw_device *cdev) { - struct set_schib_struct *s; + 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 (stsch(sch->schid, &sch->schib)) + return -ENODEV; + + if (sch->schib.scsw.fctl & SCSW_FCTL_START_FUNC) { + /* Don't copy if a start function is in progress. */ + if ((!sch->schib.scsw.actl & SCSW_ACTL_SUSPENDED) && + (sch->schib.scsw.actl & + (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) && + (!sch->schib.scsw.stctl & 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(©_block->wait); + kref_init(©_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(©_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; - s = cdev->private->cmb_wait; - cdev->private->cmb_wait = 0; - if (!s) { + copy_block = cdev->private->cmb_wait; + if (!copy_block) { WARN_ON(1); return; } - s->ret = set_schib(cdev, s->mme, s->mbfc, s->address); - wake_up(&s->wait); + kref_get(©_block->kref); + copy_block->ret = cmf_copy_block(cdev); + wake_up(©_block->wait); + kref_put(©_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); } /** @@ -343,8 +519,8 @@ struct cmb { /* insert a single device into the cmb_area list * called with cmb_area.lock held from alloc_cmb */ -static inline int -alloc_cmb_single (struct ccw_device *cdev) +static inline int alloc_cmb_single (struct ccw_device *cdev, + struct cmb_data *cmb_data) { struct cmb *cmb; struct ccw_device_private *node; @@ -358,10 +534,12 @@ alloc_cmb_single (struct ccw_device *cdev) /* find first unused cmb in cmb_area.mem. * this is a little tricky: cmb_area.list - * remains sorted by ->cmb pointers */ + * remains sorted by ->cmb->hw_data pointers */ cmb = cmb_area.mem; list_for_each_entry(node, &cmb_area.list, cmb_list) { - if ((struct cmb*)node->cmb > cmb) + struct cmb_data *data; + data = node->cmb; + if ((struct cmb*)data->hw_block > cmb) break; cmb++; } @@ -372,7 +550,8 @@ alloc_cmb_single (struct ccw_device *cdev) /* insert new cmb */ list_add_tail(&cdev->private->cmb_list, &node->cmb_list); - cdev->private->cmb = cmb; + cmb_data->hw_block = cmb; + cdev->private->cmb = cmb_data; ret = 0; out: spin_unlock_irq(cdev->ccwlock); @@ -385,7 +564,19 @@ 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) { @@ -414,29 +605,36 @@ alloc_cmb (struct ccw_device *cdev) } /* do the actual allocation */ - ret = alloc_cmb_single(cdev); + 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) +static void free_cmb(struct ccw_device *cdev) { struct ccw_device_private *priv; - - priv = cdev->private; + 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)) { @@ -451,83 +649,97 @@ out: spin_unlock(&cmb_area.lock); } -static int -set_cmb(struct ccw_device *cdev, u32 mme) +static int set_cmb(struct ccw_device *cdev, u32 mme) { u16 offset; + struct cmb_data *cmb_data; + unsigned long flags; - if (!cdev->private->cmb) + spin_lock_irqsave(cdev->ccwlock, flags); + if (!cdev->private->cmb) { + spin_unlock_irqrestore(cdev->ccwlock, flags); return -EINVAL; - - offset = mme ? (struct cmb *)cdev->private->cmb - cmb_area.mem : 0; + } + 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) +static u64 read_cmb (struct ccw_device *cdev, int index) { - /* yes, we have to put it on the stack - * because the cmb must only be accessed - * atomically, e.g. with mvc */ - struct cmb cmb; - unsigned long flags; + 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) { - spin_unlock_irqrestore(cdev->ccwlock, flags); - return 0; + ret = 0; + goto out; } - - cmb = *(struct cmb*)cdev->private->cmb; - spin_unlock_irqrestore(cdev->ccwlock, flags); + cmb = ((struct cmb_data *)cdev->private->cmb)->last_block; switch (index) { case cmb_ssch_rsch_count: - return cmb.ssch_rsch_count; + ret = cmb->ssch_rsch_count; + goto out; case cmb_sample_count: - return cmb.sample_count; + ret = cmb->sample_count; + goto out; case cmb_device_connect_time: - val = cmb.device_connect_time; + val = cmb->device_connect_time; break; case cmb_function_pending_time: - val = cmb.function_pending_time; + val = cmb->function_pending_time; break; case cmb_device_disconnect_time: - val = cmb.device_disconnect_time; + val = cmb->device_disconnect_time; break; case cmb_control_unit_queuing_time: - val = cmb.control_unit_queuing_time; + val = cmb->control_unit_queuing_time; break; case cmb_device_active_only_time: - val = cmb.device_active_only_time; + val = cmb->device_active_only_time; break; default: - return 0; + ret = 0; + goto out; } - return time_to_avg_nsec(val, cmb.sample_count); + 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) +static int readall_cmb (struct ccw_device *cdev, struct cmbdata *data) { - /* yes, we have to put it on the stack - * because the cmb must only be accessed - * atomically, e.g. with mvc */ - struct cmb cmb; - unsigned long flags; + 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); - if (!cdev->private->cmb) { - spin_unlock_irqrestore(cdev->ccwlock, flags); - return -ENODEV; + cmb_data = cdev->private->cmb; + if (!cmb_data) { + ret = -ENODEV; + goto out; } - - cmb = *(struct cmb*)cdev->private->cmb; - time = get_clock() - cdev->private->cmb_start_time; - spin_unlock_irqrestore(cdev->ccwlock, flags); + 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)); @@ -538,31 +750,32 @@ readall_cmb (struct ccw_device *cdev, struct cmbdata *data) 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; + 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->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); + = time_to_nsec(cmb->control_unit_queuing_time); data->device_active_only_time - = time_to_nsec(cmb.device_active_only_time); + = time_to_nsec(cmb->device_active_only_time); + ret = 0; +out: + spin_unlock_irqrestore(cdev->ccwlock, flags); + return ret; +} - return 0; +static void reset_cmb(struct ccw_device *cdev) +{ + cmf_generic_reset(cdev); } -static void -reset_cmb(struct ccw_device *cdev) +static void * align_cmb(void *area) { - struct cmb *cmb; - spin_lock_irq(cdev->ccwlock); - cmb = cdev->private->cmb; - if (cmb) - memset (cmb, 0, sizeof (*cmb)); - cdev->private->cmb_start_time = get_clock(); - spin_unlock_irq(cdev->ccwlock); + return area; } static struct attribute_group cmf_attr_group; @@ -574,6 +787,7 @@ static struct cmb_operations cmbops_basic = { .read = read_cmb, .readall = readall_cmb, .reset = reset_cmb, + .align = align_cmb, .attr_group = &cmf_attr_group, }; @@ -610,22 +824,34 @@ static inline struct cmbe* cmbe_align(struct cmbe *c) return (struct cmbe*)addr; } -static int -alloc_cmbe (struct ccw_device *cdev) +static int alloc_cmbe (struct ccw_device *cdev) { struct cmbe *cmbe; - cmbe = kmalloc (sizeof (*cmbe) * 2, GFP_KERNEL); + 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) { - kfree(cmbe); spin_unlock_irq(cdev->ccwlock); - return -EBUSY; + ret = -EBUSY; + goto out_free; } - - cdev->private->cmb = cmbe; + cmb_data->hw_block = cmbe; + cdev->private->cmb = cmb_data; spin_unlock_irq(cdev->ccwlock); /* activate global measurement if this is the first channel */ @@ -636,14 +862,24 @@ alloc_cmbe (struct ccw_device *cdev) 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) +static void free_cmbe (struct ccw_device *cdev) { + struct cmb_data *cmb_data; + spin_lock_irq(cdev->ccwlock); - kfree(cdev->private->cmb); + 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 */ @@ -654,89 +890,105 @@ free_cmbe (struct ccw_device *cdev) spin_unlock(&cmb_area.lock); } -static int -set_cmbe(struct ccw_device *cdev, u32 mme) +static int set_cmbe(struct ccw_device *cdev, u32 mme) { unsigned long mba; + struct cmb_data *cmb_data; + unsigned long flags; - if (!cdev->private->cmb) + spin_lock_irqsave(cdev->ccwlock, flags); + if (!cdev->private->cmb) { + spin_unlock_irqrestore(cdev->ccwlock, flags); return -EINVAL; - mba = mme ? (unsigned long) cmbe_align(cdev->private->cmb) : 0; + } + 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); } -u64 -read_cmbe (struct ccw_device *cdev, int index) +static u64 read_cmbe (struct ccw_device *cdev, int index) { - /* yes, we have to put it on the stack - * because the cmb must only be accessed - * atomically, e.g. with mvc */ - struct cmbe cmb; - unsigned long flags; + struct cmbe *cmb; + struct cmb_data *cmb_data; u32 val; + int ret; + unsigned long flags; - spin_lock_irqsave(cdev->ccwlock, flags); - if (!cdev->private->cmb) { - spin_unlock_irqrestore(cdev->ccwlock, flags); + ret = cmf_cmb_copy_wait(cdev); + if (ret < 0) return 0; - } - cmb = *cmbe_align(cdev->private->cmb); - spin_unlock_irqrestore(cdev->ccwlock, flags); + 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: - return cmb.ssch_rsch_count; + ret = cmb->ssch_rsch_count; + goto out; case cmb_sample_count: - return cmb.sample_count; + ret = cmb->sample_count; + goto out; case cmb_device_connect_time: - val = cmb.device_connect_time; + val = cmb->device_connect_time; break; case cmb_function_pending_time: - val = cmb.function_pending_time; + val = cmb->function_pending_time; break; case cmb_device_disconnect_time: - val = cmb.device_disconnect_time; + val = cmb->device_disconnect_time; break; case cmb_control_unit_queuing_time: - val = cmb.control_unit_queuing_time; + val = cmb->control_unit_queuing_time; break; case cmb_device_active_only_time: - val = cmb.device_active_only_time; + val = cmb->device_active_only_time; break; case cmb_device_busy_time: - val = cmb.device_busy_time; + val = cmb->device_busy_time; break; case cmb_initial_command_response_time: - val = cmb.initial_command_response_time; + val = cmb->initial_command_response_time; break; default: - return 0; + ret = 0; + goto out; } - return time_to_avg_nsec(val, cmb.sample_count); + 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) +static int readall_cmbe (struct ccw_device *cdev, struct cmbdata *data) { - /* yes, we have to put it on the stack - * because the cmb must only be accessed - * atomically, e.g. with mvc */ - struct cmbe cmb; - unsigned long flags; + 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); - if (!cdev->private->cmb) { - spin_unlock_irqrestore(cdev->ccwlock, flags); - return -ENODEV; + cmb_data = cdev->private->cmb; + if (!cmb_data) { + ret = -ENODEV; + goto out; } - - cmb = *cmbe_align(cdev->private->cmb); - time = get_clock() - cdev->private->cmb_start_time; - spin_unlock_irqrestore(cdev->ccwlock, flags); + 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)); @@ -746,35 +998,38 @@ readall_cmbe (struct ccw_device *cdev, struct cmbdata *data) /* 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; + 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->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); + = 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); + = 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); + = time_to_nsec(cmb->initial_command_response_time); - return 0; + ret = 0; +out: + spin_unlock_irqrestore(cdev->ccwlock, flags); + return ret; } -static void -reset_cmbe(struct ccw_device *cdev) +static void reset_cmbe(struct ccw_device *cdev) { - struct cmbe *cmb; - spin_lock_irq(cdev->ccwlock); - cmb = cmbe_align(cdev->private->cmb); - if (cmb) - memset (cmb, 0, sizeof (*cmb)); - cdev->private->cmb_start_time = get_clock(); - spin_unlock_irq(cdev->ccwlock); + cmf_generic_reset(cdev); +} + +static void * align_cmbe(void *area) +{ + return cmbe_align(area); } static struct attribute_group cmf_attr_group_ext; @@ -786,6 +1041,7 @@ static struct cmb_operations cmbops_extended = { .read = read_cmbe, .readall = readall_cmbe, .reset = reset_cmbe, + .align = align_cmbe, .attr_group = &cmf_attr_group_ext, }; @@ -803,14 +1059,19 @@ cmb_show_avg_sample_interval(struct device *dev, struct device_attribute *attr, struct ccw_device *cdev; long interval; unsigned long count; + struct cmb_data *cmb_data; cdev = to_ccwdev(dev); - interval = get_clock() - cdev->private->cmb_start_time; count = cmf_read(cdev, cmb_sample_count); - if (count) + spin_lock_irq(cdev->ccwlock); + cmb_data = cdev->private->cmb; + if (count) { + interval = cmb_data->last_update - + cdev->private->cmb_start_time; interval /= count; - else + } else interval = -1; + spin_unlock_irq(cdev->ccwlock); return sprintf(buf, "%ld\n", interval); } @@ -823,7 +1084,10 @@ cmb_show_avg_utilization(struct device *dev, struct device_attribute *attr, char int ret; ret = cmf_readall(to_ccwdev(dev), &data); - if (ret) + 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 + @@ -982,6 +1246,13 @@ 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) { -- cgit v1.2.3