diff options
Diffstat (limited to '')
| -rw-r--r-- | mm/damon/sysfs.c | 1829 |
1 files changed, 1829 insertions, 0 deletions
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c new file mode 100644 index 0000000000..b317f51dcc --- /dev/null +++ b/mm/damon/sysfs.c @@ -0,0 +1,1829 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON sysfs Interface + * + * Copyright (c) 2022 SeongJae Park <sj@kernel.org> + */ + +#include <linux/pid.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include "sysfs-common.h" + +/* + * init region directory + */ + +struct damon_sysfs_region { + struct kobject kobj; + struct damon_addr_range ar; +}; + +static struct damon_sysfs_region *damon_sysfs_region_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_region), GFP_KERNEL); +} + +static ssize_t start_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + + return sysfs_emit(buf, "%lu\n", region->ar.start); +} + +static ssize_t start_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + int err = kstrtoul(buf, 0, ®ion->ar.start); + + return err ? err : count; +} + +static ssize_t end_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + + return sysfs_emit(buf, "%lu\n", region->ar.end); +} + +static ssize_t end_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_region *region = container_of(kobj, + struct damon_sysfs_region, kobj); + int err = kstrtoul(buf, 0, ®ion->ar.end); + + return err ? err : count; +} + +static void damon_sysfs_region_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_region, kobj)); +} + +static struct kobj_attribute damon_sysfs_region_start_attr = + __ATTR_RW_MODE(start, 0600); + +static struct kobj_attribute damon_sysfs_region_end_attr = + __ATTR_RW_MODE(end, 0600); + +static struct attribute *damon_sysfs_region_attrs[] = { + &damon_sysfs_region_start_attr.attr, + &damon_sysfs_region_end_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_region); + +static const struct kobj_type damon_sysfs_region_ktype = { + .release = damon_sysfs_region_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_region_groups, +}; + +/* + * init_regions directory + */ + +struct damon_sysfs_regions { + struct kobject kobj; + struct damon_sysfs_region **regions_arr; + int nr; +}; + +static struct damon_sysfs_regions *damon_sysfs_regions_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_regions), GFP_KERNEL); +} + +static void damon_sysfs_regions_rm_dirs(struct damon_sysfs_regions *regions) +{ + struct damon_sysfs_region **regions_arr = regions->regions_arr; + int i; + + for (i = 0; i < regions->nr; i++) + kobject_put(®ions_arr[i]->kobj); + regions->nr = 0; + kfree(regions_arr); + regions->regions_arr = NULL; +} + +static int damon_sysfs_regions_add_dirs(struct damon_sysfs_regions *regions, + int nr_regions) +{ + struct damon_sysfs_region **regions_arr, *region; + int err, i; + + damon_sysfs_regions_rm_dirs(regions); + if (!nr_regions) + return 0; + + regions_arr = kmalloc_array(nr_regions, sizeof(*regions_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!regions_arr) + return -ENOMEM; + regions->regions_arr = regions_arr; + + for (i = 0; i < nr_regions; i++) { + region = damon_sysfs_region_alloc(); + if (!region) { + damon_sysfs_regions_rm_dirs(regions); + return -ENOMEM; + } + + err = kobject_init_and_add(®ion->kobj, + &damon_sysfs_region_ktype, ®ions->kobj, + "%d", i); + if (err) { + kobject_put(®ion->kobj); + damon_sysfs_regions_rm_dirs(regions); + return err; + } + + regions_arr[i] = region; + regions->nr++; + } + return 0; +} + +static ssize_t nr_regions_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_regions *regions = container_of(kobj, + struct damon_sysfs_regions, kobj); + + return sysfs_emit(buf, "%d\n", regions->nr); +} + +static ssize_t nr_regions_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_regions *regions; + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + regions = container_of(kobj, struct damon_sysfs_regions, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_regions_add_dirs(regions, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_regions_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_regions, kobj)); +} + +static struct kobj_attribute damon_sysfs_regions_nr_attr = + __ATTR_RW_MODE(nr_regions, 0600); + +static struct attribute *damon_sysfs_regions_attrs[] = { + &damon_sysfs_regions_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_regions); + +static const struct kobj_type damon_sysfs_regions_ktype = { + .release = damon_sysfs_regions_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_regions_groups, +}; + +/* + * target directory + */ + +struct damon_sysfs_target { + struct kobject kobj; + struct damon_sysfs_regions *regions; + int pid; +}; + +static struct damon_sysfs_target *damon_sysfs_target_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_target), GFP_KERNEL); +} + +static int damon_sysfs_target_add_dirs(struct damon_sysfs_target *target) +{ + struct damon_sysfs_regions *regions = damon_sysfs_regions_alloc(); + int err; + + if (!regions) + return -ENOMEM; + + err = kobject_init_and_add(®ions->kobj, &damon_sysfs_regions_ktype, + &target->kobj, "regions"); + if (err) + kobject_put(®ions->kobj); + else + target->regions = regions; + return err; +} + +static void damon_sysfs_target_rm_dirs(struct damon_sysfs_target *target) +{ + damon_sysfs_regions_rm_dirs(target->regions); + kobject_put(&target->regions->kobj); +} + +static ssize_t pid_target_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_target *target = container_of(kobj, + struct damon_sysfs_target, kobj); + + return sysfs_emit(buf, "%d\n", target->pid); +} + +static ssize_t pid_target_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_target *target = container_of(kobj, + struct damon_sysfs_target, kobj); + int err = kstrtoint(buf, 0, &target->pid); + + if (err) + return -EINVAL; + return count; +} + +static void damon_sysfs_target_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_target, kobj)); +} + +static struct kobj_attribute damon_sysfs_target_pid_attr = + __ATTR_RW_MODE(pid_target, 0600); + +static struct attribute *damon_sysfs_target_attrs[] = { + &damon_sysfs_target_pid_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_target); + +static const struct kobj_type damon_sysfs_target_ktype = { + .release = damon_sysfs_target_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_target_groups, +}; + +/* + * targets directory + */ + +struct damon_sysfs_targets { + struct kobject kobj; + struct damon_sysfs_target **targets_arr; + int nr; +}; + +static struct damon_sysfs_targets *damon_sysfs_targets_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_targets), GFP_KERNEL); +} + +static void damon_sysfs_targets_rm_dirs(struct damon_sysfs_targets *targets) +{ + struct damon_sysfs_target **targets_arr = targets->targets_arr; + int i; + + for (i = 0; i < targets->nr; i++) { + damon_sysfs_target_rm_dirs(targets_arr[i]); + kobject_put(&targets_arr[i]->kobj); + } + targets->nr = 0; + kfree(targets_arr); + targets->targets_arr = NULL; +} + +static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets, + int nr_targets) +{ + struct damon_sysfs_target **targets_arr, *target; + int err, i; + + damon_sysfs_targets_rm_dirs(targets); + if (!nr_targets) + return 0; + + targets_arr = kmalloc_array(nr_targets, sizeof(*targets_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!targets_arr) + return -ENOMEM; + targets->targets_arr = targets_arr; + + for (i = 0; i < nr_targets; i++) { + target = damon_sysfs_target_alloc(); + if (!target) { + damon_sysfs_targets_rm_dirs(targets); + return -ENOMEM; + } + + err = kobject_init_and_add(&target->kobj, + &damon_sysfs_target_ktype, &targets->kobj, + "%d", i); + if (err) + goto out; + + err = damon_sysfs_target_add_dirs(target); + if (err) + goto out; + + targets_arr[i] = target; + targets->nr++; + } + return 0; + +out: + damon_sysfs_targets_rm_dirs(targets); + kobject_put(&target->kobj); + return err; +} + +static ssize_t nr_targets_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_targets *targets = container_of(kobj, + struct damon_sysfs_targets, kobj); + + return sysfs_emit(buf, "%d\n", targets->nr); +} + +static ssize_t nr_targets_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_targets *targets; + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + targets = container_of(kobj, struct damon_sysfs_targets, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_targets_add_dirs(targets, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_targets_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_targets, kobj)); +} + +static struct kobj_attribute damon_sysfs_targets_nr_attr = + __ATTR_RW_MODE(nr_targets, 0600); + +static struct attribute *damon_sysfs_targets_attrs[] = { + &damon_sysfs_targets_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_targets); + +static const struct kobj_type damon_sysfs_targets_ktype = { + .release = damon_sysfs_targets_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_targets_groups, +}; + +/* + * intervals directory + */ + +struct damon_sysfs_intervals { + struct kobject kobj; + unsigned long sample_us; + unsigned long aggr_us; + unsigned long update_us; +}; + +static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc( + unsigned long sample_us, unsigned long aggr_us, + unsigned long update_us) +{ + struct damon_sysfs_intervals *intervals = kmalloc(sizeof(*intervals), + GFP_KERNEL); + + if (!intervals) + return NULL; + + intervals->kobj = (struct kobject){}; + intervals->sample_us = sample_us; + intervals->aggr_us = aggr_us; + intervals->update_us = update_us; + return intervals; +} + +static ssize_t sample_us_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + + return sysfs_emit(buf, "%lu\n", intervals->sample_us); +} + +static ssize_t sample_us_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + unsigned long us; + int err = kstrtoul(buf, 0, &us); + + if (err) + return err; + + intervals->sample_us = us; + return count; +} + +static ssize_t aggr_us_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + + return sysfs_emit(buf, "%lu\n", intervals->aggr_us); +} + +static ssize_t aggr_us_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + unsigned long us; + int err = kstrtoul(buf, 0, &us); + + if (err) + return err; + + intervals->aggr_us = us; + return count; +} + +static ssize_t update_us_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + + return sysfs_emit(buf, "%lu\n", intervals->update_us); +} + +static ssize_t update_us_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_intervals *intervals = container_of(kobj, + struct damon_sysfs_intervals, kobj); + unsigned long us; + int err = kstrtoul(buf, 0, &us); + + if (err) + return err; + + intervals->update_us = us; + return count; +} + +static void damon_sysfs_intervals_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_intervals, kobj)); +} + +static struct kobj_attribute damon_sysfs_intervals_sample_us_attr = + __ATTR_RW_MODE(sample_us, 0600); + +static struct kobj_attribute damon_sysfs_intervals_aggr_us_attr = + __ATTR_RW_MODE(aggr_us, 0600); + +static struct kobj_attribute damon_sysfs_intervals_update_us_attr = + __ATTR_RW_MODE(update_us, 0600); + +static struct attribute *damon_sysfs_intervals_attrs[] = { + &damon_sysfs_intervals_sample_us_attr.attr, + &damon_sysfs_intervals_aggr_us_attr.attr, + &damon_sysfs_intervals_update_us_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_intervals); + +static const struct kobj_type damon_sysfs_intervals_ktype = { + .release = damon_sysfs_intervals_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_intervals_groups, +}; + +/* + * monitoring_attrs directory + */ + +struct damon_sysfs_attrs { + struct kobject kobj; + struct damon_sysfs_intervals *intervals; + struct damon_sysfs_ul_range *nr_regions_range; +}; + +static struct damon_sysfs_attrs *damon_sysfs_attrs_alloc(void) +{ + struct damon_sysfs_attrs *attrs = kmalloc(sizeof(*attrs), GFP_KERNEL); + + if (!attrs) + return NULL; + attrs->kobj = (struct kobject){}; + return attrs; +} + +static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs) +{ + struct damon_sysfs_intervals *intervals; + struct damon_sysfs_ul_range *nr_regions_range; + int err; + + intervals = damon_sysfs_intervals_alloc(5000, 100000, 60000000); + if (!intervals) + return -ENOMEM; + + err = kobject_init_and_add(&intervals->kobj, + &damon_sysfs_intervals_ktype, &attrs->kobj, + "intervals"); + if (err) + goto put_intervals_out; + attrs->intervals = intervals; + + nr_regions_range = damon_sysfs_ul_range_alloc(10, 1000); + if (!nr_regions_range) { + err = -ENOMEM; + goto put_intervals_out; + } + + err = kobject_init_and_add(&nr_regions_range->kobj, + &damon_sysfs_ul_range_ktype, &attrs->kobj, + "nr_regions"); + if (err) + goto put_nr_regions_intervals_out; + attrs->nr_regions_range = nr_regions_range; + return 0; + +put_nr_regions_intervals_out: + kobject_put(&nr_regions_range->kobj); + attrs->nr_regions_range = NULL; +put_intervals_out: + kobject_put(&intervals->kobj); + attrs->intervals = NULL; + return err; +} + +static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs) +{ + kobject_put(&attrs->nr_regions_range->kobj); + kobject_put(&attrs->intervals->kobj); +} + +static void damon_sysfs_attrs_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_attrs, kobj)); +} + +static struct attribute *damon_sysfs_attrs_attrs[] = { + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_attrs); + +static const struct kobj_type damon_sysfs_attrs_ktype = { + .release = damon_sysfs_attrs_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_attrs_groups, +}; + +/* + * context directory + */ + +/* This should match with enum damon_ops_id */ +static const char * const damon_sysfs_ops_strs[] = { + "vaddr", + "fvaddr", + "paddr", +}; + +struct damon_sysfs_context { + struct kobject kobj; + enum damon_ops_id ops_id; + struct damon_sysfs_attrs *attrs; + struct damon_sysfs_targets *targets; + struct damon_sysfs_schemes *schemes; +}; + +static struct damon_sysfs_context *damon_sysfs_context_alloc( + enum damon_ops_id ops_id) +{ + struct damon_sysfs_context *context = kmalloc(sizeof(*context), + GFP_KERNEL); + + if (!context) + return NULL; + context->kobj = (struct kobject){}; + context->ops_id = ops_id; + return context; +} + +static int damon_sysfs_context_set_attrs(struct damon_sysfs_context *context) +{ + struct damon_sysfs_attrs *attrs = damon_sysfs_attrs_alloc(); + int err; + + if (!attrs) + return -ENOMEM; + err = kobject_init_and_add(&attrs->kobj, &damon_sysfs_attrs_ktype, + &context->kobj, "monitoring_attrs"); + if (err) + goto out; + err = damon_sysfs_attrs_add_dirs(attrs); + if (err) + goto out; + context->attrs = attrs; + return 0; + +out: + kobject_put(&attrs->kobj); + return err; +} + +static int damon_sysfs_context_set_targets(struct damon_sysfs_context *context) +{ + struct damon_sysfs_targets *targets = damon_sysfs_targets_alloc(); + int err; + + if (!targets) + return -ENOMEM; + err = kobject_init_and_add(&targets->kobj, &damon_sysfs_targets_ktype, + &context->kobj, "targets"); + if (err) { + kobject_put(&targets->kobj); + return err; + } + context->targets = targets; + return 0; +} + +static int damon_sysfs_context_set_schemes(struct damon_sysfs_context *context) +{ + struct damon_sysfs_schemes *schemes = damon_sysfs_schemes_alloc(); + int err; + + if (!schemes) + return -ENOMEM; + err = kobject_init_and_add(&schemes->kobj, &damon_sysfs_schemes_ktype, + &context->kobj, "schemes"); + if (err) { + kobject_put(&schemes->kobj); + return err; + } + context->schemes = schemes; + return 0; +} + +static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context) +{ + int err; + + err = damon_sysfs_context_set_attrs(context); + if (err) + return err; + + err = damon_sysfs_context_set_targets(context); + if (err) + goto put_attrs_out; + + err = damon_sysfs_context_set_schemes(context); + if (err) + goto put_targets_attrs_out; + return 0; + +put_targets_attrs_out: + kobject_put(&context->targets->kobj); + context->targets = NULL; +put_attrs_out: + kobject_put(&context->attrs->kobj); + context->attrs = NULL; + return err; +} + +static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context) +{ + damon_sysfs_attrs_rm_dirs(context->attrs); + kobject_put(&context->attrs->kobj); + damon_sysfs_targets_rm_dirs(context->targets); + kobject_put(&context->targets->kobj); + damon_sysfs_schemes_rm_dirs(context->schemes); + kobject_put(&context->schemes->kobj); +} + +static ssize_t avail_operations_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + enum damon_ops_id id; + int len = 0; + + for (id = 0; id < NR_DAMON_OPS; id++) { + if (!damon_is_registered_ops(id)) + continue; + len += sysfs_emit_at(buf, len, "%s\n", + damon_sysfs_ops_strs[id]); + } + return len; +} + +static ssize_t operations_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_context *context = container_of(kobj, + struct damon_sysfs_context, kobj); + + return sysfs_emit(buf, "%s\n", damon_sysfs_ops_strs[context->ops_id]); +} + +static ssize_t operations_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_context *context = container_of(kobj, + struct damon_sysfs_context, kobj); + enum damon_ops_id id; + + for (id = 0; id < NR_DAMON_OPS; id++) { + if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) { + context->ops_id = id; + return count; + } + } + return -EINVAL; +} + +static void damon_sysfs_context_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_context, kobj)); +} + +static struct kobj_attribute damon_sysfs_context_avail_operations_attr = + __ATTR_RO_MODE(avail_operations, 0400); + +static struct kobj_attribute damon_sysfs_context_operations_attr = + __ATTR_RW_MODE(operations, 0600); + +static struct attribute *damon_sysfs_context_attrs[] = { + &damon_sysfs_context_avail_operations_attr.attr, + &damon_sysfs_context_operations_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_context); + +static const struct kobj_type damon_sysfs_context_ktype = { + .release = damon_sysfs_context_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_context_groups, +}; + +/* + * contexts directory + */ + +struct damon_sysfs_contexts { + struct kobject kobj; + struct damon_sysfs_context **contexts_arr; + int nr; +}; + +static struct damon_sysfs_contexts *damon_sysfs_contexts_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_contexts), GFP_KERNEL); +} + +static void damon_sysfs_contexts_rm_dirs(struct damon_sysfs_contexts *contexts) +{ + struct damon_sysfs_context **contexts_arr = contexts->contexts_arr; + int i; + + for (i = 0; i < contexts->nr; i++) { + damon_sysfs_context_rm_dirs(contexts_arr[i]); + kobject_put(&contexts_arr[i]->kobj); + } + contexts->nr = 0; + kfree(contexts_arr); + contexts->contexts_arr = NULL; +} + +static int damon_sysfs_contexts_add_dirs(struct damon_sysfs_contexts *contexts, + int nr_contexts) +{ + struct damon_sysfs_context **contexts_arr, *context; + int err, i; + + damon_sysfs_contexts_rm_dirs(contexts); + if (!nr_contexts) + return 0; + + contexts_arr = kmalloc_array(nr_contexts, sizeof(*contexts_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!contexts_arr) + return -ENOMEM; + contexts->contexts_arr = contexts_arr; + + for (i = 0; i < nr_contexts; i++) { + context = damon_sysfs_context_alloc(DAMON_OPS_VADDR); + if (!context) { + damon_sysfs_contexts_rm_dirs(contexts); + return -ENOMEM; + } + + err = kobject_init_and_add(&context->kobj, + &damon_sysfs_context_ktype, &contexts->kobj, + "%d", i); + if (err) + goto out; + + err = damon_sysfs_context_add_dirs(context); + if (err) + goto out; + + contexts_arr[i] = context; + contexts->nr++; + } + return 0; + +out: + damon_sysfs_contexts_rm_dirs(contexts); + kobject_put(&context->kobj); + return err; +} + +static ssize_t nr_contexts_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_contexts *contexts = container_of(kobj, + struct damon_sysfs_contexts, kobj); + + return sysfs_emit(buf, "%d\n", contexts->nr); +} + +static ssize_t nr_contexts_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_contexts *contexts; + int nr, err; + + err = kstrtoint(buf, 0, &nr); + if (err) + return err; + /* TODO: support multiple contexts per kdamond */ + if (nr < 0 || 1 < nr) + return -EINVAL; + + contexts = container_of(kobj, struct damon_sysfs_contexts, kobj); + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_contexts_add_dirs(contexts, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_contexts_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_contexts, kobj)); +} + +static struct kobj_attribute damon_sysfs_contexts_nr_attr + = __ATTR_RW_MODE(nr_contexts, 0600); + +static struct attribute *damon_sysfs_contexts_attrs[] = { + &damon_sysfs_contexts_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_contexts); + +static const struct kobj_type damon_sysfs_contexts_ktype = { + .release = damon_sysfs_contexts_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_contexts_groups, +}; + +/* + * kdamond directory + */ + +struct damon_sysfs_kdamond { + struct kobject kobj; + struct damon_sysfs_contexts *contexts; + struct damon_ctx *damon_ctx; +}; + +static struct damon_sysfs_kdamond *damon_sysfs_kdamond_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_kdamond), GFP_KERNEL); +} + +static int damon_sysfs_kdamond_add_dirs(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_sysfs_contexts *contexts; + int err; + + contexts = damon_sysfs_contexts_alloc(); + if (!contexts) + return -ENOMEM; + + err = kobject_init_and_add(&contexts->kobj, + &damon_sysfs_contexts_ktype, &kdamond->kobj, + "contexts"); + if (err) { + kobject_put(&contexts->kobj); + return err; + } + kdamond->contexts = contexts; + + return err; +} + +static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond) +{ + damon_sysfs_contexts_rm_dirs(kdamond->contexts); + kobject_put(&kdamond->contexts->kobj); +} + +static bool damon_sysfs_ctx_running(struct damon_ctx *ctx) +{ + bool running; + + mutex_lock(&ctx->kdamond_lock); + running = ctx->kdamond != NULL; + mutex_unlock(&ctx->kdamond_lock); + return running; +} + +/* + * enum damon_sysfs_cmd - Commands for a specific kdamond. + */ +enum damon_sysfs_cmd { + /* @DAMON_SYSFS_CMD_ON: Turn the kdamond on. */ + DAMON_SYSFS_CMD_ON, + /* @DAMON_SYSFS_CMD_OFF: Turn the kdamond off. */ + DAMON_SYSFS_CMD_OFF, + /* @DAMON_SYSFS_CMD_COMMIT: Update kdamond inputs. */ + DAMON_SYSFS_CMD_COMMIT, + /* + * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: Update scheme stats sysfs + * files. + */ + DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS, + /* + * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: Update + * tried_regions/total_bytes sysfs files for each scheme. + */ + DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES, + /* + * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried + * regions + */ + DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS, + /* + * @DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: Clear schemes tried + * regions + */ + DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS, + /* + * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands. + */ + NR_DAMON_SYSFS_CMDS, +}; + +/* Should match with enum damon_sysfs_cmd */ +static const char * const damon_sysfs_cmd_strs[] = { + "on", + "off", + "commit", + "update_schemes_stats", + "update_schemes_tried_bytes", + "update_schemes_tried_regions", + "clear_schemes_tried_regions", +}; + +/* + * struct damon_sysfs_cmd_request - A request to the DAMON callback. + * @cmd: The command that needs to be handled by the callback. + * @kdamond: The kobject wrapper that associated to the kdamond thread. + * + * This structure represents a sysfs command request that need to access some + * DAMON context-internal data. Because DAMON context-internal data can be + * safely accessed from DAMON callbacks without additional synchronization, the + * request will be handled by the DAMON callback. None-``NULL`` @kdamond means + * the request is valid. + */ +struct damon_sysfs_cmd_request { + enum damon_sysfs_cmd cmd; + struct damon_sysfs_kdamond *kdamond; +}; + +/* Current DAMON callback request. Protected by damon_sysfs_lock. */ +static struct damon_sysfs_cmd_request damon_sysfs_cmd_request; + +static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + struct damon_ctx *ctx = kdamond->damon_ctx; + bool running; + + if (!ctx) + running = false; + else + running = damon_sysfs_ctx_running(ctx); + + return sysfs_emit(buf, "%s\n", running ? + damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] : + damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_OFF]); +} + +static int damon_sysfs_set_attrs(struct damon_ctx *ctx, + struct damon_sysfs_attrs *sys_attrs) +{ + struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals; + struct damon_sysfs_ul_range *sys_nr_regions = + sys_attrs->nr_regions_range; + struct damon_attrs attrs = { + .sample_interval = sys_intervals->sample_us, + .aggr_interval = sys_intervals->aggr_us, + .ops_update_interval = sys_intervals->update_us, + .min_nr_regions = sys_nr_regions->min, + .max_nr_regions = sys_nr_regions->max, + }; + return damon_set_attrs(ctx, &attrs); +} + +static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + bool has_pid = damon_target_has_pid(ctx); + + damon_for_each_target_safe(t, next, ctx) { + if (has_pid) + put_pid(t->pid); + damon_destroy_target(t); + } +} + +static int damon_sysfs_set_regions(struct damon_target *t, + struct damon_sysfs_regions *sysfs_regions) +{ + struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr, + sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN); + int i, err = -EINVAL; + + if (!ranges) + return -ENOMEM; + for (i = 0; i < sysfs_regions->nr; i++) { + struct damon_sysfs_region *sys_region = + sysfs_regions->regions_arr[i]; + + if (sys_region->ar.start > sys_region->ar.end) + goto out; + + ranges[i].start = sys_region->ar.start; + ranges[i].end = sys_region->ar.end; + if (i == 0) + continue; + if (ranges[i - 1].end > ranges[i].start) + goto out; + } + err = damon_set_regions(t, ranges, sysfs_regions->nr); +out: + kfree(ranges); + return err; + +} + +static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target, + struct damon_ctx *ctx) +{ + struct damon_target *t = damon_new_target(); + int err = -EINVAL; + + if (!t) + return -ENOMEM; + damon_add_target(ctx, t); + if (damon_target_has_pid(ctx)) { + t->pid = find_get_pid(sys_target->pid); + if (!t->pid) + goto destroy_targets_out; + } + err = damon_sysfs_set_regions(t, sys_target->regions); + if (err) + goto destroy_targets_out; + return 0; + +destroy_targets_out: + damon_sysfs_destroy_targets(ctx); + return err; +} + +static int damon_sysfs_update_target_pid(struct damon_target *target, int pid) +{ + struct pid *pid_new; + + pid_new = find_get_pid(pid); + if (!pid_new) + return -EINVAL; + + if (pid_new == target->pid) { + put_pid(pid_new); + return 0; + } + + put_pid(target->pid); + target->pid = pid_new; + return 0; +} + +static int damon_sysfs_update_target(struct damon_target *target, + struct damon_ctx *ctx, + struct damon_sysfs_target *sys_target) +{ + int err = 0; + + if (damon_target_has_pid(ctx)) { + err = damon_sysfs_update_target_pid(target, sys_target->pid); + if (err) + return err; + } + + /* + * Do monitoring target region boundary update only if one or more + * regions are set by the user. This is for keeping current monitoring + * target results and range easier, especially for dynamic monitoring + * target regions update ops like 'vaddr'. + */ + if (sys_target->regions->nr) + err = damon_sysfs_set_regions(target, sys_target->regions); + return err; +} + +static int damon_sysfs_set_targets(struct damon_ctx *ctx, + struct damon_sysfs_targets *sysfs_targets) +{ + struct damon_target *t, *next; + int i = 0, err; + + /* Multiple physical address space monitoring targets makes no sense */ + if (ctx->ops.id == DAMON_OPS_PADDR && sysfs_targets->nr > 1) + return -EINVAL; + + damon_for_each_target_safe(t, next, ctx) { + if (i < sysfs_targets->nr) { + err = damon_sysfs_update_target(t, ctx, + sysfs_targets->targets_arr[i]); + if (err) + return err; + } else { + if (damon_target_has_pid(ctx)) + put_pid(t->pid); + damon_destroy_target(t); + } + i++; + } + + for (; i < sysfs_targets->nr; i++) { + struct damon_sysfs_target *st = sysfs_targets->targets_arr[i]; + + err = damon_sysfs_add_target(st, ctx); + if (err) + return err; + } + return 0; +} + +static bool damon_sysfs_schemes_regions_updating; + +static void damon_sysfs_before_terminate(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + struct damon_sysfs_kdamond *kdamond; + enum damon_sysfs_cmd cmd; + + /* damon_sysfs_schemes_update_regions_stop() might not yet called */ + kdamond = damon_sysfs_cmd_request.kdamond; + cmd = damon_sysfs_cmd_request.cmd; + if (kdamond && ctx == kdamond->damon_ctx && + (cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS || + cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES) && + damon_sysfs_schemes_regions_updating) { + damon_sysfs_schemes_update_regions_stop(ctx); + damon_sysfs_schemes_regions_updating = false; + mutex_unlock(&damon_sysfs_lock); + } + + if (!damon_target_has_pid(ctx)) + return; + + mutex_lock(&ctx->kdamond_lock); + damon_for_each_target_safe(t, next, ctx) { + put_pid(t->pid); + damon_destroy_target(t); + } + mutex_unlock(&ctx->kdamond_lock); +} + +/* + * damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files. + * @kdamond: The kobject wrapper that associated to the kdamond thread. + * + * This function reads the schemes stats of specific kdamond and update the + * related values for sysfs files. This function should be called from DAMON + * callbacks while holding ``damon_syfs_lock``, to safely access the DAMON + * contexts-internal data and DAMON sysfs variables. + */ +static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + + if (!ctx) + return -EINVAL; + damon_sysfs_schemes_update_stats( + kdamond->contexts->contexts_arr[0]->schemes, ctx); + return 0; +} + +static int damon_sysfs_upd_schemes_regions_start( + struct damon_sysfs_kdamond *kdamond, bool total_bytes_only) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + + if (!ctx) + return -EINVAL; + return damon_sysfs_schemes_update_regions_start( + kdamond->contexts->contexts_arr[0]->schemes, ctx, + total_bytes_only); +} + +static int damon_sysfs_upd_schemes_regions_stop( + struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + + if (!ctx) + return -EINVAL; + return damon_sysfs_schemes_update_regions_stop(ctx); +} + +static int damon_sysfs_clear_schemes_regions( + struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + + if (!ctx) + return -EINVAL; + return damon_sysfs_schemes_clear_regions( + kdamond->contexts->contexts_arr[0]->schemes, ctx); +} + +static inline bool damon_sysfs_kdamond_running( + struct damon_sysfs_kdamond *kdamond) +{ + return kdamond->damon_ctx && + damon_sysfs_ctx_running(kdamond->damon_ctx); +} + +static int damon_sysfs_apply_inputs(struct damon_ctx *ctx, + struct damon_sysfs_context *sys_ctx) +{ + int err; + + err = damon_select_ops(ctx, sys_ctx->ops_id); + if (err) + return err; + err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs); + if (err) + return err; + err = damon_sysfs_set_targets(ctx, sys_ctx->targets); + if (err) + return err; + return damon_sysfs_set_schemes(ctx, sys_ctx->schemes); +} + +/* + * damon_sysfs_commit_input() - Commit user inputs to a running kdamond. + * @kdamond: The kobject wrapper for the associated kdamond. + * + * If the sysfs input is wrong, the kdamond will be terminated. + */ +static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond) +{ + if (!damon_sysfs_kdamond_running(kdamond)) + return -EINVAL; + /* TODO: Support multiple contexts per kdamond */ + if (kdamond->contexts->nr != 1) + return -EINVAL; + + return damon_sysfs_apply_inputs(kdamond->damon_ctx, + kdamond->contexts->contexts_arr[0]); +} + +/* + * damon_sysfs_cmd_request_callback() - DAMON callback for handling requests. + * @c: The DAMON context of the callback. + * + * This function is periodically called back from the kdamond thread for @c. + * Then, it checks if there is a waiting DAMON sysfs request and handles it. + */ +static int damon_sysfs_cmd_request_callback(struct damon_ctx *c) +{ + struct damon_sysfs_kdamond *kdamond; + bool total_bytes_only = false; + int err = 0; + + /* avoid deadlock due to concurrent state_store('off') */ + if (!damon_sysfs_schemes_regions_updating && + !mutex_trylock(&damon_sysfs_lock)) + return 0; + kdamond = damon_sysfs_cmd_request.kdamond; + if (!kdamond || kdamond->damon_ctx != c) + goto out; + switch (damon_sysfs_cmd_request.cmd) { + case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: + err = damon_sysfs_upd_schemes_stats(kdamond); + break; + case DAMON_SYSFS_CMD_COMMIT: + err = damon_sysfs_commit_input(kdamond); + break; + case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: + total_bytes_only = true; + fallthrough; + case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: + if (!damon_sysfs_schemes_regions_updating) { + err = damon_sysfs_upd_schemes_regions_start(kdamond, + total_bytes_only); + if (!err) { + damon_sysfs_schemes_regions_updating = true; + goto keep_lock_out; + } + } else { + err = damon_sysfs_upd_schemes_regions_stop(kdamond); + damon_sysfs_schemes_regions_updating = false; + } + break; + case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: + err = damon_sysfs_clear_schemes_regions(kdamond); + break; + default: + break; + } + /* Mark the request as invalid now. */ + damon_sysfs_cmd_request.kdamond = NULL; +out: + if (!damon_sysfs_schemes_regions_updating) + mutex_unlock(&damon_sysfs_lock); +keep_lock_out: + return err; +} + +static struct damon_ctx *damon_sysfs_build_ctx( + struct damon_sysfs_context *sys_ctx) +{ + struct damon_ctx *ctx = damon_new_ctx(); + int err; + + if (!ctx) + return ERR_PTR(-ENOMEM); + + err = damon_sysfs_apply_inputs(ctx, sys_ctx); + if (err) { + damon_destroy_ctx(ctx); + return ERR_PTR(err); + } + + ctx->callback.after_wmarks_check = damon_sysfs_cmd_request_callback; + ctx->callback.after_aggregation = damon_sysfs_cmd_request_callback; + ctx->callback.before_terminate = damon_sysfs_before_terminate; + return ctx; +} + +static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx; + int err; + + if (damon_sysfs_kdamond_running(kdamond)) + return -EBUSY; + if (damon_sysfs_cmd_request.kdamond == kdamond) + return -EBUSY; + /* TODO: support multiple contexts per kdamond */ + if (kdamond->contexts->nr != 1) + return -EINVAL; + + if (kdamond->damon_ctx) + damon_destroy_ctx(kdamond->damon_ctx); + kdamond->damon_ctx = NULL; + + ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + err = damon_start(&ctx, 1, false); + if (err) { + damon_destroy_ctx(ctx); + return err; + } + kdamond->damon_ctx = ctx; + return err; +} + +static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond) +{ + if (!kdamond->damon_ctx) + return -EINVAL; + return damon_stop(&kdamond->damon_ctx, 1); + /* + * To allow users show final monitoring results of already turned-off + * DAMON, we free kdamond->damon_ctx in next + * damon_sysfs_turn_damon_on(), or kdamonds_nr_store() + */ +} + +/* + * damon_sysfs_handle_cmd() - Handle a command for a specific kdamond. + * @cmd: The command to handle. + * @kdamond: The kobject wrapper for the associated kdamond. + * + * This function handles a DAMON sysfs command for a kdamond. For commands + * that need to access running DAMON context-internal data, it requests + * handling of the command to the DAMON callback + * (@damon_sysfs_cmd_request_callback()) and wait until it is properly handled, + * or the context is completed. + * + * Return: 0 on success, negative error code otherwise. + */ +static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd, + struct damon_sysfs_kdamond *kdamond) +{ + bool need_wait = true; + + /* Handle commands that doesn't access DAMON context-internal data */ + switch (cmd) { + case DAMON_SYSFS_CMD_ON: + return damon_sysfs_turn_damon_on(kdamond); + case DAMON_SYSFS_CMD_OFF: + return damon_sysfs_turn_damon_off(kdamond); + default: + break; + } + + /* Pass the command to DAMON callback for safe DAMON context access */ + if (damon_sysfs_cmd_request.kdamond) + return -EBUSY; + if (!damon_sysfs_kdamond_running(kdamond)) + return -EINVAL; + damon_sysfs_cmd_request.cmd = cmd; + damon_sysfs_cmd_request.kdamond = kdamond; + + /* + * wait until damon_sysfs_cmd_request_callback() handles the request + * from kdamond context + */ + mutex_unlock(&damon_sysfs_lock); + while (need_wait) { + schedule_timeout_idle(msecs_to_jiffies(100)); + if (!mutex_trylock(&damon_sysfs_lock)) + continue; + if (!damon_sysfs_cmd_request.kdamond) { + /* damon_sysfs_cmd_request_callback() handled */ + need_wait = false; + } else if (!damon_sysfs_kdamond_running(kdamond)) { + /* kdamond has already finished */ + need_wait = false; + damon_sysfs_cmd_request.kdamond = NULL; + } + mutex_unlock(&damon_sysfs_lock); + } + mutex_lock(&damon_sysfs_lock); + return 0; +} + +static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + enum damon_sysfs_cmd cmd; + ssize_t ret = -EINVAL; + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + for (cmd = 0; cmd < NR_DAMON_SYSFS_CMDS; cmd++) { + if (sysfs_streq(buf, damon_sysfs_cmd_strs[cmd])) { + ret = damon_sysfs_handle_cmd(cmd, kdamond); + break; + } + } + mutex_unlock(&damon_sysfs_lock); + if (!ret) + ret = count; + return ret; +} + +static ssize_t pid_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + struct damon_ctx *ctx; + int pid = -1; + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + ctx = kdamond->damon_ctx; + if (!ctx) + goto out; + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) + pid = ctx->kdamond->pid; + mutex_unlock(&ctx->kdamond_lock); +out: + mutex_unlock(&damon_sysfs_lock); + return sysfs_emit(buf, "%d\n", pid); +} + +static void damon_sysfs_kdamond_release(struct kobject *kobj) +{ + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + + if (kdamond->damon_ctx) + damon_destroy_ctx(kdamond->damon_ctx); + kfree(kdamond); +} + +static struct kobj_attribute damon_sysfs_kdamond_state_attr = + __ATTR_RW_MODE(state, 0600); + +static struct kobj_attribute damon_sysfs_kdamond_pid_attr = + __ATTR_RO_MODE(pid, 0400); + +static struct attribute *damon_sysfs_kdamond_attrs[] = { + &damon_sysfs_kdamond_state_attr.attr, + &damon_sysfs_kdamond_pid_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_kdamond); + +static const struct kobj_type damon_sysfs_kdamond_ktype = { + .release = damon_sysfs_kdamond_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_kdamond_groups, +}; + +/* + * kdamonds directory + */ + +struct damon_sysfs_kdamonds { + struct kobject kobj; + struct damon_sysfs_kdamond **kdamonds_arr; + int nr; +}; + +static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_kdamonds), GFP_KERNEL); +} + +static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds) +{ + struct damon_sysfs_kdamond **kdamonds_arr = kdamonds->kdamonds_arr; + int i; + + for (i = 0; i < kdamonds->nr; i++) { + damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]); + kobject_put(&kdamonds_arr[i]->kobj); + } + kdamonds->nr = 0; + kfree(kdamonds_arr); + kdamonds->kdamonds_arr = NULL; +} + +static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds, + int nr_kdamonds) +{ + int i; + + for (i = 0; i < nr_kdamonds; i++) { + if (damon_sysfs_kdamond_running(kdamonds[i]) || + damon_sysfs_cmd_request.kdamond == kdamonds[i]) + return true; + } + + return false; +} + +static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds, + int nr_kdamonds) +{ + struct damon_sysfs_kdamond **kdamonds_arr, *kdamond; + int err, i; + + if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr)) + return -EBUSY; + + damon_sysfs_kdamonds_rm_dirs(kdamonds); + if (!nr_kdamonds) + return 0; + + kdamonds_arr = kmalloc_array(nr_kdamonds, sizeof(*kdamonds_arr), + GFP_KERNEL | __GFP_NOWARN); + if (!kdamonds_arr) + return -ENOMEM; + kdamonds->kdamonds_arr = kdamonds_arr; + + for (i = 0; i < nr_kdamonds; i++) { + kdamond = damon_sysfs_kdamond_alloc(); + if (!kdamond) { + damon_sysfs_kdamonds_rm_dirs(kdamonds); + return -ENOMEM; + } + + err = kobject_init_and_add(&kdamond->kobj, + &damon_sysfs_kdamond_ktype, &kdamonds->kobj, + "%d", i); + if (err) + goto out; + + err = damon_sysfs_kdamond_add_dirs(kdamond); + if (err) + goto out; + + kdamonds_arr[i] = kdamond; + kdamonds->nr++; + } + return 0; + +out: + damon_sysfs_kdamonds_rm_dirs(kdamonds); + kobject_put(&kdamond->kobj); + return err; +} + +static ssize_t nr_kdamonds_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_kdamonds *kdamonds = container_of(kobj, + struct damon_sysfs_kdamonds, kobj); + + return sysfs_emit(buf, "%d\n", kdamonds->nr); +} + +static ssize_t nr_kdamonds_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_kdamonds *kdamonds; + int nr, err; + + err = kstrtoint(buf, 0, &nr); + if (err) + return err; + if (nr < 0) + return -EINVAL; + + kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + +static void damon_sysfs_kdamonds_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_kdamonds, kobj)); +} + +static struct kobj_attribute damon_sysfs_kdamonds_nr_attr = + __ATTR_RW_MODE(nr_kdamonds, 0600); + +static struct attribute *damon_sysfs_kdamonds_attrs[] = { + &damon_sysfs_kdamonds_nr_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_kdamonds); + +static const struct kobj_type damon_sysfs_kdamonds_ktype = { + .release = damon_sysfs_kdamonds_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_kdamonds_groups, +}; + +/* + * damon user interface directory + */ + +struct damon_sysfs_ui_dir { + struct kobject kobj; + struct damon_sysfs_kdamonds *kdamonds; +}; + +static struct damon_sysfs_ui_dir *damon_sysfs_ui_dir_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_ui_dir), GFP_KERNEL); +} + +static int damon_sysfs_ui_dir_add_dirs(struct damon_sysfs_ui_dir *ui_dir) +{ + struct damon_sysfs_kdamonds *kdamonds; + int err; + + kdamonds = damon_sysfs_kdamonds_alloc(); + if (!kdamonds) + return -ENOMEM; + + err = kobject_init_and_add(&kdamonds->kobj, + &damon_sysfs_kdamonds_ktype, &ui_dir->kobj, + "kdamonds"); + if (err) { + kobject_put(&kdamonds->kobj); + return err; + } + ui_dir->kdamonds = kdamonds; + return err; +} + +static void damon_sysfs_ui_dir_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_ui_dir, kobj)); +} + +static struct attribute *damon_sysfs_ui_dir_attrs[] = { + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_ui_dir); + +static const struct kobj_type damon_sysfs_ui_dir_ktype = { + .release = damon_sysfs_ui_dir_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_ui_dir_groups, +}; + +static int __init damon_sysfs_init(void) +{ + struct kobject *damon_sysfs_root; + struct damon_sysfs_ui_dir *admin; + int err; + + damon_sysfs_root = kobject_create_and_add("damon", mm_kobj); + if (!damon_sysfs_root) + return -ENOMEM; + + admin = damon_sysfs_ui_dir_alloc(); + if (!admin) { + kobject_put(damon_sysfs_root); + return -ENOMEM; + } + err = kobject_init_and_add(&admin->kobj, &damon_sysfs_ui_dir_ktype, + damon_sysfs_root, "admin"); + if (err) + goto out; + err = damon_sysfs_ui_dir_add_dirs(admin); + if (err) + goto out; + return 0; + +out: + kobject_put(&admin->kobj); + kobject_put(damon_sysfs_root); + return err; +} +subsys_initcall(damon_sysfs_init); |