static int bc_ioacct_notify(struct vnotifier_block *self,
unsigned long event, void *arg, int old_ret)
{
struct user_beancounter *ub;
unsigned long *vm_events;
unsigned long long bin, bout;
int i;
if (event != VIRTINFO_VMSTAT)
return old_ret;
ub = top_beancounter(get_exec_ub());
if (ub == get_ub0())
return old_ret;
/* Think over: do we need to account here bytes_dirty_missed? */
bout = ub->bytes_wrote;
bin = 0;
for_each_online_cpu(i) {
bout += per_cpu_ptr(ub->ub_percpu, i)->bytes_wrote;
bin += per_cpu_ptr(ub->ub_percpu, i)->bytes_read;
}
/* convert to Kbytes */
bout >>= 10;
bin >>= 10;
vm_events = ((unsigned long *)arg) + NR_VM_ZONE_STAT_ITEMS;
vm_events[PGPGOUT] = (unsigned long)bout;
vm_events[PGPGIN] = (unsigned long)bin;
return NOTIFY_OK;
}
/* Find an unused file structure and return a pointer to it.
* Returns NULL, if there are no more free file structures or
* we run out of memory.
*
* Be very careful using this. You are responsible for
* getting write access to any mount that you might assign
* to this filp, if it is opened for write. If this is not
* done, you will imbalance int the mount's writer count
* and a warning at __fput() time.
*/
struct file *get_empty_filp(void)
{
const struct cred *cred = current_cred();
static long old_max;
struct file * f;
int acct;
acct = (get_exec_ub() == get_ub0());
/*
* Privileged users can go above max_files
*/
if (acct && get_nr_files() >= files_stat.max_files &&
!capable(CAP_SYS_ADMIN)) {
/*
* percpu_counters are inaccurate. Do an expensive check before
* we go and fail.
*/
if (percpu_counter_sum_positive(&nr_files) >= files_stat.max_files)
goto over;
}
f = kmem_cache_zalloc(filp_cachep, GFP_KERNEL);
if (f == NULL)
goto fail;
if (ub_file_charge(f))
goto fail_ch;
if (acct)
percpu_counter_inc(&nr_files);
if (security_file_alloc(f))
goto fail_sec;
INIT_LIST_HEAD(&f->f_u.fu_list);
atomic_long_set(&f->f_count, 1);
rwlock_init(&f->f_owner.lock);
f->f_cred = get_cred(cred);
spin_lock_init(&f->f_lock);
eventpoll_init_file(f);
/* f->f_version: 0 */
return f;
over:
/* Ran out of filps - report that */
if (get_nr_files() > old_max) {
pr_info("VFS: file-max limit %lu reached\n", get_max_files());
old_max = get_nr_files();
}
goto fail;
fail_sec:
file_free(f);
fail:
return NULL;
fail_ch:
kmem_cache_free(filp_cachep, f);
return NULL;
}
static inline void file_free(struct file *f)
{
file_check_state(f);
if (f->f_ub == get_ub0())
percpu_counter_dec(&nr_files);
ub_file_uncharge(f);
call_rcu(&f->f_u.fu_rcuhead, file_free_rcu);
}