static DEFINE_SPINLOCK(ext_devt_lock);
static DEFINE_IDR(ext_devt_idr);
-static const struct device_type disk_type;
-
static void disk_check_events(struct disk_events *ev,
unsigned int *clearing_ptr);
static void disk_alloc_events(struct gendisk *disk);
}
EXPORT_SYMBOL(bdevname);
-#ifdef CONFIG_SMP
static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat)
{
int cpu;
stat->io_ticks += ptr->io_ticks;
}
}
-#else /* CONFIG_SMP */
-static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat)
-{
- memcpy(stat, &part->dkstats, sizeof(struct disk_stats));
-}
-#endif /* CONFIG_SMP */
-
-void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, int rw)
-{
- if (queue_is_mq(q))
- return;
-
- part_stat_local_inc(part, in_flight[rw]);
- if (part->partno)
- part_stat_local_inc(&part_to_disk(part)->part0, in_flight[rw]);
-}
-
-void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw)
-{
- if (queue_is_mq(q))
- return;
-
- part_stat_local_dec(part, in_flight[rw]);
- if (part->partno)
- part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]);
-}
static unsigned int part_in_flight(struct request_queue *q,
struct hd_struct *part)
{
+ unsigned int inflight = 0;
int cpu;
- unsigned int inflight;
-
- if (queue_is_mq(q)) {
- return blk_mq_in_flight(q, part);
- }
- inflight = 0;
for_each_possible_cpu(cpu) {
inflight += part_stat_local_read_cpu(part, in_flight[0], cpu) +
part_stat_local_read_cpu(part, in_flight[1], cpu);
{
int cpu;
- if (queue_is_mq(q)) {
- blk_mq_in_flight_rw(q, part, inflight);
- return;
- }
-
inflight[0] = 0;
inflight[1] = 0;
for_each_possible_cpu(cpu) {
* primarily used for stats accounting.
*
* CONTEXT:
- * RCU read locked. The returned partition pointer is valid only
- * while preemption is disabled.
+ * RCU read locked. The returned partition pointer is always valid
+ * because its refcount is grabbed except for part0, which lifetime
+ * is same with the disk.
*
* RETURNS:
* Found partition on success, part0 is returned if no partition matches
+ * or the matched partition is being deleted.
*/
struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
{
struct hd_struct *part;
int i;
+ rcu_read_lock();
ptbl = rcu_dereference(disk->part_tbl);
part = rcu_dereference(ptbl->last_lookup);
- if (part && sector_in_part(part, sector))
- return part;
+ if (part && sector_in_part(part, sector) && hd_struct_try_get(part))
+ goto out_unlock;
for (i = 1; i < ptbl->len; i++) {
part = rcu_dereference(ptbl->part[i]);
if (part && sector_in_part(part, sector)) {
+ /*
+ * only live partition can be cached for lookup,
+ * so use-after-free on cached & deleting partition
+ * can be avoided
+ */
+ if (!hd_struct_try_get(part))
+ break;
rcu_assign_pointer(ptbl->last_lookup, part);
- return part;
+ goto out_unlock;
}
}
- return &disk->part0;
+
+ part = &disk->part0;
+out_unlock:
+ rcu_read_unlock();
+ return part;
}
/**
disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
disk->flags |= GENHD_FL_NO_PART_SCAN;
} else {
+ struct backing_dev_info *bdi = disk->queue->backing_dev_info;
+ struct device *dev = disk_to_dev(disk);
int ret;
/* Register BDI before referencing it from bdev */
- disk_to_dev(disk)->devt = devt;
- ret = bdi_register_owner(disk->queue->backing_dev_info,
- disk_to_dev(disk));
+ dev->devt = devt;
+ ret = bdi_register(bdi, "%u:%u", MAJOR(devt), MINOR(devt));
WARN_ON(ret);
+ bdi_set_owner(bdi, dev);
blk_register_region(disk_devt(disk), disk->minors, NULL,
exact_match, exact_lock, disk);
}
}
EXPORT_SYMBOL(device_add_disk_no_queue_reg);
+static void invalidate_partition(struct gendisk *disk, int partno)
+{
+ struct block_device *bdev;
+
+ bdev = bdget_disk(disk, partno);
+ if (!bdev)
+ return;
+
+ fsync_bdev(bdev);
+ __invalidate_device(bdev, true);
+
+ /*
+ * Unhash the bdev inode for this device so that it gets evicted as soon
+ * as last inode reference is dropped.
+ */
+ remove_inode_hash(bdev->bd_inode);
+ bdput(bdev);
+}
+
+/**
+ * del_gendisk - remove the gendisk
+ * @disk: the struct gendisk to remove
+ *
+ * Removes the gendisk and all its associated resources. This deletes the
+ * partitions associated with the gendisk, and unregisters the associated
+ * request_queue.
+ *
+ * This is the counter to the respective __device_add_disk() call.
+ *
+ * The final removal of the struct gendisk happens when its refcount reaches 0
+ * with put_disk(), which should be called after del_gendisk(), if
+ * __device_add_disk() was used.
+ *
+ * Drivers exist which depend on the release of the gendisk to be synchronous,
+ * it should not be deferred.
+ *
+ * Context: can sleep
+ */
void del_gendisk(struct gendisk *disk)
{
struct disk_part_iter piter;
struct hd_struct *part;
+ might_sleep();
+
blk_integrity_del(disk);
disk_del_events(disk);
DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
while ((part = disk_part_iter_next(&piter))) {
invalidate_partition(disk, part->partno);
- bdev_unhash_inode(part_devt(part));
- delete_partition(disk, part->partno);
+ delete_partition(disk, part);
}
disk_part_iter_exit(&piter);
invalidate_partition(disk, 0);
- bdev_unhash_inode(disk_devt(disk));
set_capacity(disk, 0);
disk->flags &= ~GENHD_FL_UP;
up_write(&disk->lookup_sem);
*
* This function gets the structure containing partitioning
* information for the given device @devt.
+ *
+ * Context: can sleep
*/
struct gendisk *get_gendisk(dev_t devt, int *partno)
{
struct gendisk *disk = NULL;
+ might_sleep();
+
if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
struct kobject *kobj;
unsigned int inflight;
part_stat_read_all(p, &stat);
- inflight = part_in_flight(q, p);
+ if (queue_is_mq(q))
+ inflight = blk_mq_in_flight(q, p);
+ else
+ inflight = part_in_flight(q, p);
return sprintf(buf,
"%8lu %8lu %8llu %8u "
struct request_queue *q = part_to_disk(p)->queue;
unsigned int inflight[2];
- part_in_flight_rw(q, p, inflight);
+ if (queue_is_mq(q))
+ blk_mq_in_flight_rw(q, p, inflight);
+ else
+ part_in_flight_rw(q, p, inflight);
+
return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]);
}
return 0;
}
+/**
+ * disk_release - releases all allocated resources of the gendisk
+ * @dev: the device representing this disk
+ *
+ * This function releases all allocated resources of the gendisk.
+ *
+ * The struct gendisk refcount is incremented with get_gendisk() or
+ * get_disk_and_module(), and its refcount is decremented with
+ * put_disk_and_module() or put_disk(). Once the refcount reaches 0 this
+ * function is called.
+ *
+ * Drivers which used __device_add_disk() have a gendisk with a request_queue
+ * assigned. Since the request_queue sits on top of the gendisk for these
+ * drivers we also call blk_put_queue() for them, and we expect the
+ * request_queue refcount to reach 0 at this point, and so the request_queue
+ * will also be freed prior to the disk.
+ *
+ * Context: can sleep
+ */
static void disk_release(struct device *dev)
{
struct gendisk *disk = dev_to_disk(dev);
+ might_sleep();
+
blk_free_devt(dev->devt);
disk_release_events(disk);
kfree(disk->random);
return NULL;
}
-static const struct device_type disk_type = {
+const struct device_type disk_type = {
.name = "disk",
.groups = disk_attr_groups,
.release = disk_release,
disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
while ((hd = disk_part_iter_next(&piter))) {
part_stat_read_all(hd, &stat);
- inflight = part_in_flight(gp->queue, hd);
+ if (queue_is_mq(gp->queue))
+ inflight = blk_mq_in_flight(gp->queue, hd);
+ else
+ inflight = part_in_flight(gp->queue, hd);
seq_printf(seqf, "%4d %7d %s "
"%lu %lu %lu %u "
disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
if (disk) {
- if (!init_part_stats(&disk->part0)) {
+ disk->part0.dkstats = alloc_percpu(struct disk_stats);
+ if (!disk->part0.dkstats) {
kfree(disk);
return NULL;
}
init_rwsem(&disk->lookup_sem);
disk->node_id = node_id;
if (disk_expand_part_tbl(disk, 0)) {
- free_part_stats(&disk->part0);
+ free_percpu(disk->part0.dkstats);
kfree(disk);
return NULL;
}
* TODO: Ideally set_capacity() and get_capacity() should be
* converted to make use of bd_mutex and sequence counters.
*/
- seqcount_init(&disk->part0.nr_sects_seq);
+ hd_sects_seq_init(&disk->part0);
if (hd_ref_init(&disk->part0)) {
hd_free_part(&disk->part0);
kfree(disk);
}
EXPORT_SYMBOL(__alloc_disk_node);
+/**
+ * get_disk_and_module - increments the gendisk and gendisk fops module refcount
+ * @disk: the struct gendisk to increment the refcount for
+ *
+ * This increments the refcount for the struct gendisk, and the gendisk's
+ * fops module owner.
+ *
+ * Context: Any context.
+ */
struct kobject *get_disk_and_module(struct gendisk *disk)
{
struct module *owner;
}
EXPORT_SYMBOL(get_disk_and_module);
+/**
+ * put_disk - decrements the gendisk refcount
+ * @disk: the struct gendisk to decrement the refcount for
+ *
+ * This decrements the refcount for the struct gendisk. When this reaches 0
+ * we'll have disk_release() called.
+ *
+ * Context: Any context, but the last reference must not be dropped from
+ * atomic context.
+ */
void put_disk(struct gendisk *disk)
{
if (disk)
}
EXPORT_SYMBOL(put_disk);
-/*
+/**
+ * put_disk_and_module - decrements the module and gendisk refcount
+ * @disk: the struct gendisk to decrement the refcount for
+ *
* This is a counterpart of get_disk_and_module() and thus also of
* get_gendisk().
+ *
+ * Context: Any context, but the last reference must not be dropped from
+ * atomic context.
*/
void put_disk_and_module(struct gendisk *disk)
{
EXPORT_SYMBOL(bdev_read_only);
-int invalidate_partition(struct gendisk *disk, int partno)
-{
- int res = 0;
- struct block_device *bdev = bdget_disk(disk, partno);
- if (bdev) {
- fsync_bdev(bdev);
- res = __invalidate_device(bdev, true);
- bdput(bdev);
- }
- return res;
-}
-
-EXPORT_SYMBOL(invalidate_partition);
-
/*
* Disk events - monitor disk events like media change and eject request.
*/
*/
unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
{
- const struct block_device_operations *bdops = disk->fops;
struct disk_events *ev = disk->ev;
unsigned int pending;
unsigned int clearing = mask;
- if (!ev) {
- /* for drivers still using the old ->media_changed method */
- if ((mask & DISK_EVENT_MEDIA_CHANGE) &&
- bdops->media_changed && bdops->media_changed(disk))
- return DISK_EVENT_MEDIA_CHANGE;
+ if (!ev)
return 0;
- }
disk_block_events(disk);
projects / linux-2.6-microblaze.git / blobdiff