659 lines
16 KiB
C
659 lines
16 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) 1991-1998 Linus Torvalds
|
|
* Re-organised Feb 1998 Russell King
|
|
*/
|
|
#include <linux/fs.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/ctype.h>
|
|
#include <linux/genhd.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/blktrace_api.h>
|
|
#include <linux/raid/detect.h>
|
|
#include "check.h"
|
|
|
|
static int (*check_part[])(struct parsed_partitions *) = {
|
|
/*
|
|
* Probe partition formats with tables at disk address 0
|
|
* that also have an ADFS boot block at 0xdc0.
|
|
*/
|
|
#ifdef CONFIG_ACORN_PARTITION_ICS
|
|
adfspart_check_ICS,
|
|
#endif
|
|
#ifdef CONFIG_ACORN_PARTITION_POWERTEC
|
|
adfspart_check_POWERTEC,
|
|
#endif
|
|
#ifdef CONFIG_ACORN_PARTITION_EESOX
|
|
adfspart_check_EESOX,
|
|
#endif
|
|
|
|
/*
|
|
* Now move on to formats that only have partition info at
|
|
* disk address 0xdc0. Since these may also have stale
|
|
* PC/BIOS partition tables, they need to come before
|
|
* the msdos entry.
|
|
*/
|
|
#ifdef CONFIG_ACORN_PARTITION_CUMANA
|
|
adfspart_check_CUMANA,
|
|
#endif
|
|
#ifdef CONFIG_ACORN_PARTITION_ADFS
|
|
adfspart_check_ADFS,
|
|
#endif
|
|
|
|
#ifdef CONFIG_CMDLINE_PARTITION
|
|
cmdline_partition,
|
|
#endif
|
|
#ifdef CONFIG_EFI_PARTITION
|
|
efi_partition, /* this must come before msdos */
|
|
#endif
|
|
#ifdef CONFIG_SGI_PARTITION
|
|
sgi_partition,
|
|
#endif
|
|
#ifdef CONFIG_LDM_PARTITION
|
|
ldm_partition, /* this must come before msdos */
|
|
#endif
|
|
#ifdef CONFIG_MSDOS_PARTITION
|
|
msdos_partition,
|
|
#endif
|
|
#ifdef CONFIG_OSF_PARTITION
|
|
osf_partition,
|
|
#endif
|
|
#ifdef CONFIG_SUN_PARTITION
|
|
sun_partition,
|
|
#endif
|
|
#ifdef CONFIG_AMIGA_PARTITION
|
|
amiga_partition,
|
|
#endif
|
|
#ifdef CONFIG_ATARI_PARTITION
|
|
atari_partition,
|
|
#endif
|
|
#ifdef CONFIG_MAC_PARTITION
|
|
mac_partition,
|
|
#endif
|
|
#ifdef CONFIG_ULTRIX_PARTITION
|
|
ultrix_partition,
|
|
#endif
|
|
#ifdef CONFIG_IBM_PARTITION
|
|
ibm_partition,
|
|
#endif
|
|
#ifdef CONFIG_KARMA_PARTITION
|
|
karma_partition,
|
|
#endif
|
|
#ifdef CONFIG_SYSV68_PARTITION
|
|
sysv68_partition,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
|
|
{
|
|
struct parsed_partitions *state;
|
|
int nr;
|
|
|
|
state = kzalloc(sizeof(*state), GFP_KERNEL);
|
|
if (!state)
|
|
return NULL;
|
|
|
|
nr = disk_max_parts(hd);
|
|
state->parts = vzalloc(array_size(nr, sizeof(state->parts[0])));
|
|
if (!state->parts) {
|
|
kfree(state);
|
|
return NULL;
|
|
}
|
|
|
|
state->limit = nr;
|
|
|
|
return state;
|
|
}
|
|
|
|
static void free_partitions(struct parsed_partitions *state)
|
|
{
|
|
vfree(state->parts);
|
|
kfree(state);
|
|
}
|
|
|
|
static struct parsed_partitions *check_partition(struct gendisk *hd,
|
|
struct block_device *bdev)
|
|
{
|
|
struct parsed_partitions *state;
|
|
int i, res, err;
|
|
|
|
state = allocate_partitions(hd);
|
|
if (!state)
|
|
return NULL;
|
|
state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
|
|
if (!state->pp_buf) {
|
|
free_partitions(state);
|
|
return NULL;
|
|
}
|
|
state->pp_buf[0] = '\0';
|
|
|
|
state->bdev = bdev;
|
|
disk_name(hd, 0, state->name);
|
|
snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
|
|
if (isdigit(state->name[strlen(state->name)-1]))
|
|
sprintf(state->name, "p");
|
|
|
|
i = res = err = 0;
|
|
while (!res && check_part[i]) {
|
|
memset(state->parts, 0, state->limit * sizeof(state->parts[0]));
|
|
res = check_part[i++](state);
|
|
if (res < 0) {
|
|
/*
|
|
* We have hit an I/O error which we don't report now.
|
|
* But record it, and let the others do their job.
|
|
*/
|
|
err = res;
|
|
res = 0;
|
|
}
|
|
|
|
}
|
|
if (res > 0) {
|
|
printk(KERN_INFO "%s", state->pp_buf);
|
|
|
|
free_page((unsigned long)state->pp_buf);
|
|
return state;
|
|
}
|
|
if (state->access_beyond_eod)
|
|
err = -ENOSPC;
|
|
/*
|
|
* The partition is unrecognized. So report I/O errors if there were any
|
|
*/
|
|
if (err)
|
|
res = err;
|
|
if (res) {
|
|
strlcat(state->pp_buf,
|
|
" unable to read partition table\n", PAGE_SIZE);
|
|
printk(KERN_INFO "%s", state->pp_buf);
|
|
}
|
|
|
|
free_page((unsigned long)state->pp_buf);
|
|
free_partitions(state);
|
|
return ERR_PTR(res);
|
|
}
|
|
|
|
static ssize_t part_partition_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct hd_struct *p = dev_to_part(dev);
|
|
|
|
return sprintf(buf, "%d\n", p->partno);
|
|
}
|
|
|
|
static ssize_t part_start_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct hd_struct *p = dev_to_part(dev);
|
|
|
|
return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
|
|
}
|
|
|
|
static ssize_t part_ro_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct hd_struct *p = dev_to_part(dev);
|
|
return sprintf(buf, "%d\n", p->policy ? 1 : 0);
|
|
}
|
|
|
|
static ssize_t part_alignment_offset_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct hd_struct *p = dev_to_part(dev);
|
|
return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
|
|
}
|
|
|
|
static ssize_t part_discard_alignment_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct hd_struct *p = dev_to_part(dev);
|
|
return sprintf(buf, "%u\n", p->discard_alignment);
|
|
}
|
|
|
|
static DEVICE_ATTR(partition, 0444, part_partition_show, NULL);
|
|
static DEVICE_ATTR(start, 0444, part_start_show, NULL);
|
|
static DEVICE_ATTR(size, 0444, part_size_show, NULL);
|
|
static DEVICE_ATTR(ro, 0444, part_ro_show, NULL);
|
|
static DEVICE_ATTR(alignment_offset, 0444, part_alignment_offset_show, NULL);
|
|
static DEVICE_ATTR(discard_alignment, 0444, part_discard_alignment_show, NULL);
|
|
static DEVICE_ATTR(stat, 0444, part_stat_show, NULL);
|
|
static DEVICE_ATTR(inflight, 0444, part_inflight_show, NULL);
|
|
#ifdef CONFIG_FAIL_MAKE_REQUEST
|
|
static struct device_attribute dev_attr_fail =
|
|
__ATTR(make-it-fail, 0644, part_fail_show, part_fail_store);
|
|
#endif
|
|
|
|
static struct attribute *part_attrs[] = {
|
|
&dev_attr_partition.attr,
|
|
&dev_attr_start.attr,
|
|
&dev_attr_size.attr,
|
|
&dev_attr_ro.attr,
|
|
&dev_attr_alignment_offset.attr,
|
|
&dev_attr_discard_alignment.attr,
|
|
&dev_attr_stat.attr,
|
|
&dev_attr_inflight.attr,
|
|
#ifdef CONFIG_FAIL_MAKE_REQUEST
|
|
&dev_attr_fail.attr,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group part_attr_group = {
|
|
.attrs = part_attrs,
|
|
};
|
|
|
|
static const struct attribute_group *part_attr_groups[] = {
|
|
&part_attr_group,
|
|
#ifdef CONFIG_BLK_DEV_IO_TRACE
|
|
&blk_trace_attr_group,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
static void part_release(struct device *dev)
|
|
{
|
|
struct hd_struct *p = dev_to_part(dev);
|
|
blk_free_devt(dev->devt);
|
|
hd_free_part(p);
|
|
kfree(p);
|
|
}
|
|
|
|
static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
|
|
{
|
|
struct hd_struct *part = dev_to_part(dev);
|
|
|
|
add_uevent_var(env, "PARTN=%u", part->partno);
|
|
if (part->info && part->info->volname[0])
|
|
add_uevent_var(env, "PARTNAME=%s", part->info->volname);
|
|
return 0;
|
|
}
|
|
|
|
struct device_type part_type = {
|
|
.name = "partition",
|
|
.groups = part_attr_groups,
|
|
.release = part_release,
|
|
.uevent = part_uevent,
|
|
};
|
|
|
|
static void delete_partition_work_fn(struct work_struct *work)
|
|
{
|
|
struct hd_struct *part = container_of(to_rcu_work(work), struct hd_struct,
|
|
rcu_work);
|
|
|
|
part->start_sect = 0;
|
|
part->nr_sects = 0;
|
|
part_stat_set_all(part, 0);
|
|
put_device(part_to_dev(part));
|
|
}
|
|
|
|
void __delete_partition(struct percpu_ref *ref)
|
|
{
|
|
struct hd_struct *part = container_of(ref, struct hd_struct, ref);
|
|
INIT_RCU_WORK(&part->rcu_work, delete_partition_work_fn);
|
|
queue_rcu_work(system_wq, &part->rcu_work);
|
|
}
|
|
|
|
/*
|
|
* Must be called either with bd_mutex held, before a disk can be opened or
|
|
* after all disk users are gone.
|
|
*/
|
|
void delete_partition(struct gendisk *disk, int partno)
|
|
{
|
|
struct disk_part_tbl *ptbl =
|
|
rcu_dereference_protected(disk->part_tbl, 1);
|
|
struct hd_struct *part;
|
|
|
|
if (partno >= ptbl->len)
|
|
return;
|
|
|
|
part = rcu_dereference_protected(ptbl->part[partno], 1);
|
|
if (!part)
|
|
return;
|
|
|
|
rcu_assign_pointer(ptbl->part[partno], NULL);
|
|
rcu_assign_pointer(ptbl->last_lookup, NULL);
|
|
kobject_put(part->holder_dir);
|
|
device_del(part_to_dev(part));
|
|
|
|
/*
|
|
* Remove gendisk pointer from idr so that it cannot be looked up
|
|
* while RCU period before freeing gendisk is running to prevent
|
|
* use-after-free issues. Note that the device number stays
|
|
* "in-use" until we really free the gendisk.
|
|
*/
|
|
blk_invalidate_devt(part_devt(part));
|
|
hd_struct_kill(part);
|
|
}
|
|
|
|
static ssize_t whole_disk_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return 0;
|
|
}
|
|
static DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
|
|
|
|
/*
|
|
* Must be called either with bd_mutex held, before a disk can be opened or
|
|
* after all disk users are gone.
|
|
*/
|
|
struct hd_struct *add_partition(struct gendisk *disk, int partno,
|
|
sector_t start, sector_t len, int flags,
|
|
struct partition_meta_info *info)
|
|
{
|
|
struct hd_struct *p;
|
|
dev_t devt = MKDEV(0, 0);
|
|
struct device *ddev = disk_to_dev(disk);
|
|
struct device *pdev;
|
|
struct disk_part_tbl *ptbl;
|
|
const char *dname;
|
|
int err;
|
|
|
|
/*
|
|
* Partitions are not supported on zoned block devices that are used as
|
|
* such.
|
|
*/
|
|
switch (disk->queue->limits.zoned) {
|
|
case BLK_ZONED_HM:
|
|
pr_warn("%s: partitions not supported on host managed zoned block device\n",
|
|
disk->disk_name);
|
|
return ERR_PTR(-ENXIO);
|
|
case BLK_ZONED_HA:
|
|
pr_info("%s: disabling host aware zoned block device support due to partitions\n",
|
|
disk->disk_name);
|
|
disk->queue->limits.zoned = BLK_ZONED_NONE;
|
|
break;
|
|
case BLK_ZONED_NONE:
|
|
break;
|
|
}
|
|
|
|
err = disk_expand_part_tbl(disk, partno);
|
|
if (err)
|
|
return ERR_PTR(err);
|
|
ptbl = rcu_dereference_protected(disk->part_tbl, 1);
|
|
|
|
if (ptbl->part[partno])
|
|
return ERR_PTR(-EBUSY);
|
|
|
|
p = kzalloc(sizeof(*p), GFP_KERNEL);
|
|
if (!p)
|
|
return ERR_PTR(-EBUSY);
|
|
|
|
if (!init_part_stats(p)) {
|
|
err = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
|
|
seqcount_init(&p->nr_sects_seq);
|
|
pdev = part_to_dev(p);
|
|
|
|
p->start_sect = start;
|
|
p->alignment_offset =
|
|
queue_limit_alignment_offset(&disk->queue->limits, start);
|
|
p->discard_alignment =
|
|
queue_limit_discard_alignment(&disk->queue->limits, start);
|
|
p->nr_sects = len;
|
|
p->partno = partno;
|
|
p->policy = get_disk_ro(disk);
|
|
|
|
if (info) {
|
|
struct partition_meta_info *pinfo;
|
|
|
|
pinfo = kzalloc_node(sizeof(*pinfo), GFP_KERNEL, disk->node_id);
|
|
if (!pinfo) {
|
|
err = -ENOMEM;
|
|
goto out_free_stats;
|
|
}
|
|
memcpy(pinfo, info, sizeof(*info));
|
|
p->info = pinfo;
|
|
}
|
|
|
|
dname = dev_name(ddev);
|
|
if (isdigit(dname[strlen(dname) - 1]))
|
|
dev_set_name(pdev, "%sp%d", dname, partno);
|
|
else
|
|
dev_set_name(pdev, "%s%d", dname, partno);
|
|
|
|
device_initialize(pdev);
|
|
pdev->class = &block_class;
|
|
pdev->type = &part_type;
|
|
pdev->parent = ddev;
|
|
|
|
err = blk_alloc_devt(p, &devt);
|
|
if (err)
|
|
goto out_free_info;
|
|
pdev->devt = devt;
|
|
|
|
/* delay uevent until 'holders' subdir is created */
|
|
dev_set_uevent_suppress(pdev, 1);
|
|
err = device_add(pdev);
|
|
if (err)
|
|
goto out_put;
|
|
|
|
err = -ENOMEM;
|
|
p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
|
|
if (!p->holder_dir)
|
|
goto out_del;
|
|
|
|
dev_set_uevent_suppress(pdev, 0);
|
|
if (flags & ADDPART_FLAG_WHOLEDISK) {
|
|
err = device_create_file(pdev, &dev_attr_whole_disk);
|
|
if (err)
|
|
goto out_del;
|
|
}
|
|
|
|
err = hd_ref_init(p);
|
|
if (err) {
|
|
if (flags & ADDPART_FLAG_WHOLEDISK)
|
|
goto out_remove_file;
|
|
goto out_del;
|
|
}
|
|
|
|
/* everything is up and running, commence */
|
|
rcu_assign_pointer(ptbl->part[partno], p);
|
|
|
|
/* suppress uevent if the disk suppresses it */
|
|
if (!dev_get_uevent_suppress(ddev))
|
|
kobject_uevent(&pdev->kobj, KOBJ_ADD);
|
|
return p;
|
|
|
|
out_free_info:
|
|
kfree(p->info);
|
|
out_free_stats:
|
|
free_part_stats(p);
|
|
out_free:
|
|
kfree(p);
|
|
return ERR_PTR(err);
|
|
out_remove_file:
|
|
device_remove_file(pdev, &dev_attr_whole_disk);
|
|
out_del:
|
|
kobject_put(p->holder_dir);
|
|
device_del(pdev);
|
|
out_put:
|
|
put_device(pdev);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
static bool disk_unlock_native_capacity(struct gendisk *disk)
|
|
{
|
|
const struct block_device_operations *bdops = disk->fops;
|
|
|
|
if (bdops->unlock_native_capacity &&
|
|
!(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
|
|
printk(KERN_CONT "enabling native capacity\n");
|
|
bdops->unlock_native_capacity(disk);
|
|
disk->flags |= GENHD_FL_NATIVE_CAPACITY;
|
|
return true;
|
|
} else {
|
|
printk(KERN_CONT "truncated\n");
|
|
return false;
|
|
}
|
|
}
|
|
|
|
int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev)
|
|
{
|
|
struct disk_part_iter piter;
|
|
struct hd_struct *part;
|
|
int res;
|
|
|
|
if (!disk_part_scan_enabled(disk))
|
|
return 0;
|
|
if (bdev->bd_part_count)
|
|
return -EBUSY;
|
|
res = invalidate_partition(disk, 0);
|
|
if (res)
|
|
return res;
|
|
|
|
disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
|
|
while ((part = disk_part_iter_next(&piter)))
|
|
delete_partition(disk, part->partno);
|
|
disk_part_iter_exit(&piter);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev,
|
|
struct parsed_partitions *state, int p)
|
|
{
|
|
sector_t size = state->parts[p].size;
|
|
sector_t from = state->parts[p].from;
|
|
struct hd_struct *part;
|
|
|
|
if (!size)
|
|
return true;
|
|
|
|
if (from >= get_capacity(disk)) {
|
|
printk(KERN_WARNING
|
|
"%s: p%d start %llu is beyond EOD, ",
|
|
disk->disk_name, p, (unsigned long long) from);
|
|
if (disk_unlock_native_capacity(disk))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
if (from + size > get_capacity(disk)) {
|
|
printk(KERN_WARNING
|
|
"%s: p%d size %llu extends beyond EOD, ",
|
|
disk->disk_name, p, (unsigned long long) size);
|
|
|
|
if (disk_unlock_native_capacity(disk))
|
|
return false;
|
|
|
|
/*
|
|
* We can not ignore partitions of broken tables created by for
|
|
* example camera firmware, but we limit them to the end of the
|
|
* disk to avoid creating invalid block devices.
|
|
*/
|
|
size = get_capacity(disk) - from;
|
|
}
|
|
|
|
part = add_partition(disk, p, from, size, state->parts[p].flags,
|
|
&state->parts[p].info);
|
|
if (IS_ERR(part) && PTR_ERR(part) != -ENXIO) {
|
|
printk(KERN_ERR " %s: p%d could not be added: %ld\n",
|
|
disk->disk_name, p, -PTR_ERR(part));
|
|
return true;
|
|
}
|
|
|
|
if (IS_BUILTIN(CONFIG_BLK_DEV_MD) &&
|
|
(state->parts[p].flags & ADDPART_FLAG_RAID))
|
|
md_autodetect_dev(part_to_dev(part)->devt);
|
|
|
|
return true;
|
|
}
|
|
|
|
int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
|
|
{
|
|
struct parsed_partitions *state;
|
|
int ret = -EAGAIN, p, highest;
|
|
|
|
if (!disk_part_scan_enabled(disk))
|
|
return 0;
|
|
|
|
state = check_partition(disk, bdev);
|
|
if (!state)
|
|
return 0;
|
|
if (IS_ERR(state)) {
|
|
/*
|
|
* I/O error reading the partition table. If we tried to read
|
|
* beyond EOD, retry after unlocking the native capacity.
|
|
*/
|
|
if (PTR_ERR(state) == -ENOSPC) {
|
|
printk(KERN_WARNING "%s: partition table beyond EOD, ",
|
|
disk->disk_name);
|
|
if (disk_unlock_native_capacity(disk))
|
|
return -EAGAIN;
|
|
}
|
|
return -EIO;
|
|
}
|
|
|
|
/*
|
|
* Partitions are not supported on host managed zoned block devices.
|
|
*/
|
|
if (disk->queue->limits.zoned == BLK_ZONED_HM) {
|
|
pr_warn("%s: ignoring partition table on host managed zoned block device\n",
|
|
disk->disk_name);
|
|
ret = 0;
|
|
goto out_free_state;
|
|
}
|
|
|
|
/*
|
|
* If we read beyond EOD, try unlocking native capacity even if the
|
|
* partition table was successfully read as we could be missing some
|
|
* partitions.
|
|
*/
|
|
if (state->access_beyond_eod) {
|
|
printk(KERN_WARNING
|
|
"%s: partition table partially beyond EOD, ",
|
|
disk->disk_name);
|
|
if (disk_unlock_native_capacity(disk))
|
|
goto out_free_state;
|
|
}
|
|
|
|
/* tell userspace that the media / partition table may have changed */
|
|
kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
|
|
|
|
/*
|
|
* Detect the highest partition number and preallocate disk->part_tbl.
|
|
* This is an optimization and not strictly necessary.
|
|
*/
|
|
for (p = 1, highest = 0; p < state->limit; p++)
|
|
if (state->parts[p].size)
|
|
highest = p;
|
|
disk_expand_part_tbl(disk, highest);
|
|
|
|
for (p = 1; p < state->limit; p++)
|
|
if (!blk_add_partition(disk, bdev, state, p))
|
|
goto out_free_state;
|
|
|
|
ret = 0;
|
|
out_free_state:
|
|
free_partitions(state);
|
|
return ret;
|
|
}
|
|
|
|
void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p)
|
|
{
|
|
struct address_space *mapping = state->bdev->bd_inode->i_mapping;
|
|
struct page *page;
|
|
|
|
if (n >= get_capacity(state->bdev->bd_disk)) {
|
|
state->access_beyond_eod = true;
|
|
return NULL;
|
|
}
|
|
|
|
page = read_mapping_page(mapping,
|
|
(pgoff_t)(n >> (PAGE_SHIFT - 9)), NULL);
|
|
if (IS_ERR(page))
|
|
goto out;
|
|
if (PageError(page))
|
|
goto out_put_page;
|
|
|
|
p->v = page;
|
|
return (unsigned char *)page_address(page) +
|
|
((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << SECTOR_SHIFT);
|
|
out_put_page:
|
|
put_page(page);
|
|
out:
|
|
p->v = NULL;
|
|
return NULL;
|
|
}
|