diff options
| -rw-r--r-- | drivers/hwtracing/stm/core.c | 140 | ||||
| -rw-r--r-- | drivers/hwtracing/stm/policy.c | 145 | ||||
| -rw-r--r-- | drivers/hwtracing/stm/stm.h | 51 |
3 files changed, 318 insertions, 18 deletions
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 17198e79df3e..915af2541dcd 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -316,11 +316,26 @@ static int stm_output_assign(struct stm_device *stm, unsigned int width, output->master = midx; output->channel = cidx; output->nr_chans = width; + if (stm->pdrv->output_open) { + void *priv = stp_policy_node_priv(policy_node); + + if (WARN_ON_ONCE(!priv)) + goto unlock; + + /* configfs subsys mutex is held by the caller */ + ret = stm->pdrv->output_open(priv, output); + if (ret) + goto unlock; + } + stm_output_claim(stm, output); dev_dbg(&stm->dev, "assigned %u:%u (+%u)\n", midx, cidx, width); ret = 0; unlock: + if (ret) + output->nr_chans = 0; + spin_unlock(&output->lock); spin_unlock(&stm->mc_lock); @@ -333,6 +348,8 @@ static void stm_output_free(struct stm_device *stm, struct stm_output *output) spin_lock(&output->lock); if (output->nr_chans) stm_output_disclaim(stm, output); + if (stm->pdrv && stm->pdrv->output_close) + stm->pdrv->output_close(output); spin_unlock(&output->lock); spin_unlock(&stm->mc_lock); } @@ -349,6 +366,127 @@ static int major_match(struct device *dev, const void *data) return MAJOR(dev->devt) == major; } +/* + * Framing protocol management + * Modules can implement STM protocol drivers and (un-)register them + * with the STM class framework. + */ +static struct list_head stm_pdrv_head; +static struct mutex stm_pdrv_mutex; + +struct stm_pdrv_entry { + struct list_head entry; + const struct stm_protocol_driver *pdrv; + const struct config_item_type *node_type; +}; + +static const struct stm_pdrv_entry * +__stm_lookup_protocol(const char *name) +{ + struct stm_pdrv_entry *pe; + + /* + * If no name is given (NULL or ""), fall back to "p_basic". + */ + if (!name || !*name) + name = "p_basic"; + + list_for_each_entry(pe, &stm_pdrv_head, entry) { + if (!strcmp(name, pe->pdrv->name)) + return pe; + } + + return NULL; +} + +int stm_register_protocol(const struct stm_protocol_driver *pdrv) +{ + struct stm_pdrv_entry *pe = NULL; + int ret = -ENOMEM; + + mutex_lock(&stm_pdrv_mutex); + + if (__stm_lookup_protocol(pdrv->name)) { + ret = -EEXIST; + goto unlock; + } + + pe = kzalloc(sizeof(*pe), GFP_KERNEL); + if (!pe) + goto unlock; + + if (pdrv->policy_attr) { + pe->node_type = get_policy_node_type(pdrv->policy_attr); + if (!pe->node_type) + goto unlock; + } + + list_add_tail(&pe->entry, &stm_pdrv_head); + pe->pdrv = pdrv; + + ret = 0; +unlock: + mutex_unlock(&stm_pdrv_mutex); + + if (ret) + kfree(pe); + + return ret; +} +EXPORT_SYMBOL_GPL(stm_register_protocol); + +void stm_unregister_protocol(const struct stm_protocol_driver *pdrv) +{ + struct stm_pdrv_entry *pe, *iter; + + mutex_lock(&stm_pdrv_mutex); + + list_for_each_entry_safe(pe, iter, &stm_pdrv_head, entry) { + if (pe->pdrv == pdrv) { + list_del(&pe->entry); + + if (pe->node_type) { + kfree(pe->node_type->ct_attrs); + kfree(pe->node_type); + } + kfree(pe); + break; + } + } + + mutex_unlock(&stm_pdrv_mutex); +} +EXPORT_SYMBOL_GPL(stm_unregister_protocol); + +static bool stm_get_protocol(const struct stm_protocol_driver *pdrv) +{ + return try_module_get(pdrv->owner); +} + +void stm_put_protocol(const struct stm_protocol_driver *pdrv) +{ + module_put(pdrv->owner); +} + +int stm_lookup_protocol(const char *name, + const struct stm_protocol_driver **pdrv, + const struct config_item_type **node_type) +{ + const struct stm_pdrv_entry *pe; + + mutex_lock(&stm_pdrv_mutex); + + pe = __stm_lookup_protocol(name); + if (pe && pe->pdrv && stm_get_protocol(pe->pdrv)) { + *pdrv = pe->pdrv; + *node_type = pe->node_type; + } + + mutex_unlock(&stm_pdrv_mutex); + + return pe ? 0 : -ENOENT; +} + static int stm_char_open(struct inode *inode, struct file *file) { struct stm_file *stmf; @@ -1176,6 +1314,8 @@ static int __init stm_core_init(void) goto err_src; init_srcu_struct(&stm_source_srcu); + INIT_LIST_HEAD(&stm_pdrv_head); + mutex_init(&stm_pdrv_mutex); stm_core_up++; diff --git a/drivers/hwtracing/stm/policy.c b/drivers/hwtracing/stm/policy.c index a505f055f464..8bc90432ae69 100644 --- a/drivers/hwtracing/stm/policy.c +++ b/drivers/hwtracing/stm/policy.c @@ -33,8 +33,18 @@ struct stp_policy_node { unsigned int last_master; unsigned int first_channel; unsigned int last_channel; + /* this is the one that's exposed to the attributes */ + unsigned char priv[0]; }; +void *stp_policy_node_priv(struct stp_policy_node *pn) +{ + if (!pn) + return NULL; + + return pn->priv; +} + static struct configfs_subsystem stp_policy_subsys; void stp_policy_node_get_ranges(struct stp_policy_node *policy_node, @@ -68,6 +78,14 @@ to_stp_policy_node(struct config_item *item) NULL; } +void *to_pdrv_policy_node(struct config_item *item) +{ + struct stp_policy_node *node = to_stp_policy_node(item); + + return stp_policy_node_priv(node); +} +EXPORT_SYMBOL_GPL(to_pdrv_policy_node); + static ssize_t stp_policy_node_masters_show(struct config_item *item, char *page) { @@ -163,7 +181,9 @@ unlock: static void stp_policy_node_release(struct config_item *item) { - kfree(to_stp_policy_node(item)); + struct stp_policy_node *node = to_stp_policy_node(item); + + kfree(node); } static struct configfs_item_operations stp_policy_node_item_ops = { @@ -182,10 +202,61 @@ static struct configfs_attribute *stp_policy_node_attrs[] = { static const struct config_item_type stp_policy_type; static const struct config_item_type stp_policy_node_type; +/* lifted from arch/x86/events/core.c */ +static struct configfs_attribute **merge_attr(struct configfs_attribute **a, struct configfs_attribute **b) +{ + struct configfs_attribute **new; + int j, i; + + for (j = 0; a[j]; j++) + ; + for (i = 0; b[i]; i++) + j++; + j++; + + new = kmalloc_array(j, sizeof(struct configfs_attribute *), + GFP_KERNEL); + if (!new) + return NULL; + + j = 0; + for (i = 0; a[i]; i++) + new[j++] = a[i]; + for (i = 0; b[i]; i++) + new[j++] = b[i]; + new[j] = NULL; + + return new; +} + +const struct config_item_type * +get_policy_node_type(struct configfs_attribute **attrs) +{ + struct config_item_type *type; + struct configfs_attribute **merged; + + type = kmemdup(&stp_policy_node_type, sizeof(stp_policy_node_type), + GFP_KERNEL); + if (!type) + return NULL; + + merged = merge_attr(stp_policy_node_attrs, attrs); + if (!merged) { + kfree(type); + return NULL; + } + + type->ct_attrs = merged; + + return type; +} + static struct config_group * stp_policy_node_make(struct config_group *group, const char *name) { + const struct config_item_type *type = &stp_policy_node_type; struct stp_policy_node *policy_node, *parent_node; + const struct stm_protocol_driver *pdrv; struct stp_policy *policy; if (group->cg_item.ci_type == &stp_policy_type) { @@ -199,12 +270,20 @@ stp_policy_node_make(struct config_group *group, const char *name) if (!policy->stm) return ERR_PTR(-ENODEV); - policy_node = kzalloc(sizeof(struct stp_policy_node), GFP_KERNEL); + pdrv = policy->stm->pdrv; + policy_node = + kzalloc(offsetof(struct stp_policy_node, priv[pdrv->priv_sz]), + GFP_KERNEL); if (!policy_node) return ERR_PTR(-ENOMEM); - config_group_init_type_name(&policy_node->group, name, - &stp_policy_node_type); + if (pdrv->policy_node_init) + pdrv->policy_node_init((void *)policy_node->priv); + + if (policy->stm->pdrv_node_type) + type = policy->stm->pdrv_node_type; + + config_group_init_type_name(&policy_node->group, name, type); policy_node->policy = policy; @@ -254,8 +333,25 @@ static ssize_t stp_policy_device_show(struct config_item *item, CONFIGFS_ATTR_RO(stp_policy_, device); +static ssize_t stp_policy_protocol_show(struct config_item *item, + char *page) +{ + struct stp_policy *policy = to_stp_policy(item); + ssize_t count; + + count = sprintf(page, "%s\n", + (policy && policy->stm) ? + policy->stm->pdrv->name : + "<none>"); + + return count; +} + +CONFIGFS_ATTR_RO(stp_policy_, protocol); + static struct configfs_attribute *stp_policy_attrs[] = { &stp_policy_attr_device, + &stp_policy_attr_protocol, NULL, }; @@ -276,6 +372,7 @@ void stp_policy_unbind(struct stp_policy *policy) stm->policy = NULL; policy->stm = NULL; + stm_put_protocol(stm->pdrv); stm_put_device(stm); } @@ -313,9 +410,12 @@ static const struct config_item_type stp_policy_type = { static struct config_group * stp_policy_make(struct config_group *group, const char *name) { + const struct config_item_type *pdrv_node_type; + const struct stm_protocol_driver *pdrv; + char *devname, *proto, *p; struct config_group *ret; struct stm_device *stm; - char *devname, *p; + int err; devname = kasprintf(GFP_KERNEL, "%s", name); if (!devname) @@ -326,6 +426,7 @@ stp_policy_make(struct config_group *group, const char *name) * <device_name> is the name of an existing stm device; may * contain dots; * <policy_name> is an arbitrary string; may not contain dots + * <device_name>:<protocol_name>.<policy_name> */ p = strrchr(devname, '.'); if (!p) { @@ -335,11 +436,29 @@ stp_policy_make(struct config_group *group, const char *name) *p = '\0'; + /* + * look for ":<protocol_name>": + * + no protocol suffix: fall back to whatever is available; + * + unknown protocol: fail the whole thing + */ + proto = strrchr(devname, ':'); + if (proto) + *proto++ = '\0'; + stm = stm_find_device(devname); + if (!stm) { + kfree(devname); + return ERR_PTR(-ENODEV); + } + + err = stm_lookup_protocol(proto, &pdrv, &pdrv_node_type); kfree(devname); - if (!stm) + /* We don't have any protocol drivers yet */ + if (err != -ENOENT) { + stm_put_device(stm); return ERR_PTR(-ENODEV); + } mutex_lock(&stm->policy_mutex); if (stm->policy) { @@ -349,21 +468,27 @@ stp_policy_make(struct config_group *group, const char *name) stm->policy = kzalloc(sizeof(*stm->policy), GFP_KERNEL); if (!stm->policy) { - ret = ERR_PTR(-ENOMEM); - goto unlock_policy; + mutex_unlock(&stm->policy_mutex); + stm_put_protocol(pdrv); + stm_put_device(stm); + return ERR_PTR(-ENOMEM); } config_group_init_type_name(&stm->policy->group, name, &stp_policy_type); - stm->policy->stm = stm; + stm->pdrv = pdrv; + stm->pdrv_node_type = pdrv_node_type; + stm->policy->stm = stm; ret = &stm->policy->group; unlock_policy: mutex_unlock(&stm->policy_mutex); - if (IS_ERR(ret)) + if (IS_ERR(ret)) { + stm_put_protocol(stm->pdrv); stm_put_device(stm); + } return ret; } diff --git a/drivers/hwtracing/stm/stm.h b/drivers/hwtracing/stm/stm.h index e5df08ae59cf..ed7f3d07fa47 100644 --- a/drivers/hwtracing/stm/stm.h +++ b/drivers/hwtracing/stm/stm.h @@ -10,20 +10,17 @@ #ifndef _STM_STM_H_ #define _STM_STM_H_ +#include <linux/configfs.h> + struct stp_policy; struct stp_policy_node; +struct stm_protocol_driver; -struct stp_policy_node * -stp_policy_node_lookup(struct stm_device *stm, char *s); -void stp_policy_node_put(struct stp_policy_node *policy_node); -void stp_policy_unbind(struct stp_policy *policy); - -void stp_policy_node_get_ranges(struct stp_policy_node *policy_node, - unsigned int *mstart, unsigned int *mend, - unsigned int *cstart, unsigned int *cend); int stp_configfs_init(void); void stp_configfs_exit(void); +void *stp_policy_node_priv(struct stp_policy_node *pn); + struct stp_master { unsigned int nr_free; unsigned long chan_map[0]; @@ -40,6 +37,9 @@ struct stm_device { struct mutex link_mutex; spinlock_t link_lock; struct list_head link_list; + /* framing protocol in use */ + const struct stm_protocol_driver *pdrv; + const struct config_item_type *pdrv_node_type; /* master allocation */ spinlock_t mc_lock; struct stp_master *masters[0]; @@ -48,11 +48,24 @@ struct stm_device { #define to_stm_device(_d) \ container_of((_d), struct stm_device, dev) +struct stp_policy_node * +stp_policy_node_lookup(struct stm_device *stm, char *s); +void stp_policy_node_put(struct stp_policy_node *policy_node); +void stp_policy_unbind(struct stp_policy *policy); + +void stp_policy_node_get_ranges(struct stp_policy_node *policy_node, + unsigned int *mstart, unsigned int *mend, + unsigned int *cstart, unsigned int *cend); + +const struct config_item_type * +get_policy_node_type(struct configfs_attribute **attrs); + struct stm_output { spinlock_t lock; unsigned int master; unsigned int channel; unsigned int nr_chans; + void *pdrv_private; }; struct stm_file { @@ -76,4 +89,26 @@ struct stm_source_device { #define to_stm_source_device(_d) \ container_of((_d), struct stm_source_device, dev) +void *to_pdrv_policy_node(struct config_item *item); + +struct stm_protocol_driver { + struct module *owner; + const char *name; + ssize_t (*write)(struct stm_data *data, + struct stm_output *output, unsigned int chan, + const char *buf, size_t count); + void (*policy_node_init)(void *arg); + int (*output_open)(void *priv, struct stm_output *output); + void (*output_close)(struct stm_output *output); + ssize_t priv_sz; + struct configfs_attribute **policy_attr; +}; + +int stm_register_protocol(const struct stm_protocol_driver *pdrv); +void stm_unregister_protocol(const struct stm_protocol_driver *pdrv); +int stm_lookup_protocol(const char *name, + const struct stm_protocol_driver **pdrv, + const struct config_item_type **type); +void stm_put_protocol(const struct stm_protocol_driver *pdrv); + #endif /* _STM_STM_H_ */ |