inflight[1] = 0;
}
-struct block_device *__disk_get_part(struct gendisk *disk, int partno)
-{
- struct disk_part_tbl *ptbl = rcu_dereference(disk->part_tbl);
-
- if (unlikely(partno < 0 || partno >= ptbl->len))
- return NULL;
- return rcu_dereference(ptbl->part[partno]);
-}
-
/**
* disk_part_iter_init - initialize partition iterator
* @piter: iterator to initialize
void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
unsigned int flags)
{
- struct disk_part_tbl *ptbl;
-
- rcu_read_lock();
- ptbl = rcu_dereference(disk->part_tbl);
-
piter->disk = disk;
piter->part = NULL;
-
- if (flags & DISK_PITER_REVERSE)
- piter->idx = ptbl->len - 1;
- else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0))
+ if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0))
piter->idx = 0;
else
piter->idx = 1;
-
piter->flags = flags;
-
- rcu_read_unlock();
}
-EXPORT_SYMBOL_GPL(disk_part_iter_init);
/**
* disk_part_iter_next - proceed iterator to the next partition and return it
*/
struct block_device *disk_part_iter_next(struct disk_part_iter *piter)
{
- struct disk_part_tbl *ptbl;
- int inc, end;
+ struct block_device *part;
+ unsigned long idx;
/* put the last partition */
disk_part_iter_exit(piter);
- /* get part_tbl */
rcu_read_lock();
- ptbl = rcu_dereference(piter->disk->part_tbl);
-
- /* determine iteration parameters */
- if (piter->flags & DISK_PITER_REVERSE) {
- inc = -1;
- if (piter->flags & (DISK_PITER_INCL_PART0 |
- DISK_PITER_INCL_EMPTY_PART0))
- end = -1;
- else
- end = 0;
- } else {
- inc = 1;
- end = ptbl->len;
- }
-
- /* iterate to the next partition */
- for (; piter->idx != end; piter->idx += inc) {
- struct block_device *part;
-
- part = rcu_dereference(ptbl->part[piter->idx]);
- if (!part)
- continue;
- piter->part = bdgrab(part);
- if (!piter->part)
- continue;
+ xa_for_each_start(&piter->disk->part_tbl, idx, part, piter->idx) {
if (!bdev_nr_sectors(part) &&
!(piter->flags & DISK_PITER_INCL_EMPTY) &&
!(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
- piter->idx == 0)) {
- bdput(piter->part);
- piter->part = NULL;
+ piter->idx == 0))
continue;
- }
- piter->idx += inc;
+ piter->part = bdgrab(part);
+ if (!piter->part)
+ continue;
+ piter->idx = idx + 1;
break;
}
-
rcu_read_unlock();
return piter->part;
}
-EXPORT_SYMBOL_GPL(disk_part_iter_next);
/**
* disk_part_iter_exit - finish up partition iteration
bdput(piter->part);
piter->part = NULL;
}
-EXPORT_SYMBOL_GPL(disk_part_iter_exit);
-
-static inline int sector_in_part(struct block_device *part, sector_t sector)
-{
- return part->bd_start_sect <= sector &&
- sector < part->bd_start_sect + bdev_nr_sectors(part);
-}
-
-/**
- * disk_map_sector_rcu - map sector to partition
- * @disk: gendisk of interest
- * @sector: sector to map
- *
- * Find out which partition @sector maps to on @disk. This is
- * primarily used for stats accounting.
- *
- * CONTEXT:
- * RCU read locked.
- *
- * RETURNS:
- * Found partition on success, part0 is returned if no partition matches
- * or the matched partition is being deleted.
- */
-struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
-{
- struct disk_part_tbl *ptbl;
- struct block_device *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))
- goto out_unlock;
-
- for (i = 1; i < ptbl->len; i++) {
- part = rcu_dereference(ptbl->part[i]);
- if (part && sector_in_part(part, sector)) {
- rcu_assign_pointer(ptbl->last_lookup, part);
- goto out_unlock;
- }
- }
-
- part = disk->part0;
-out_unlock:
- rcu_read_unlock();
- return part;
-}
-
-/**
- * disk_has_partitions
- * @disk: gendisk of interest
- *
- * Walk through the partition table and check if valid partition exists.
- *
- * CONTEXT:
- * Don't care.
- *
- * RETURNS:
- * True if the gendisk has at least one valid non-zero size partition.
- * Otherwise false.
- */
-bool disk_has_partitions(struct gendisk *disk)
-{
- struct disk_part_tbl *ptbl;
- int i;
- bool ret = false;
-
- rcu_read_lock();
- ptbl = rcu_dereference(disk->part_tbl);
-
- /* Iterate partitions skipping the whole device at index 0 */
- for (i = 1; i < ptbl->len; i++) {
- if (rcu_dereference(ptbl->part[i])) {
- ret = true;
- break;
- }
- }
-
- rcu_read_unlock();
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(disk_has_partitions);
/*
* Can be deleted altogether. Later.
return buf;
}
+void disk_uevent(struct gendisk *disk, enum kobject_action action)
+{
+ struct disk_part_iter piter;
+ struct block_device *part;
+
+ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+ while ((part = disk_part_iter_next(&piter)))
+ kobject_uevent(bdev_kobj(part), action);
+ disk_part_iter_exit(&piter);
+}
+EXPORT_SYMBOL_GPL(disk_uevent);
+
static void disk_scan_partitions(struct gendisk *disk)
{
struct block_device *bdev;
const struct attribute_group **groups)
{
struct device *ddev = disk_to_dev(disk);
- struct disk_part_iter piter;
- struct block_device *part;
int err;
ddev->parent = parent;
disk_scan_partitions(disk);
- /* announce disk after possible partitions are created */
+ /* announce the disk and partitions after all partitions are created */
dev_set_uevent_suppress(ddev, 0);
- kobject_uevent(&ddev->kobj, KOBJ_ADD);
-
- /* announce possible partitions */
- disk_part_iter_init(&piter, disk, 0);
- while ((part = disk_part_iter_next(&piter)))
- kobject_uevent(bdev_kobj(part), KOBJ_ADD);
- disk_part_iter_exit(&piter);
+ disk_uevent(disk, KOBJ_ADD);
if (disk->queue->backing_dev_info->dev) {
err = sysfs_create_link(&ddev->kobj,
down_write(&bdev_lookup_sem);
/* invalidate stuff */
- disk_part_iter_init(&piter, disk,
- DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
+ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
while ((part = disk_part_iter_next(&piter))) {
invalidate_partition(part);
delete_partition(part);
struct block_device *bdev = NULL;
rcu_read_lock();
- bdev = __disk_get_part(disk, partno);
+ bdev = xa_load(&disk->part_tbl, partno);
if (bdev && !bdgrab(bdev))
bdev = NULL;
rcu_read_unlock();
NULL
};
-/**
- * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
- * @disk: disk to replace part_tbl for
- * @new_ptbl: new part_tbl to install
- *
- * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
- * original ptbl is freed using RCU callback.
- *
- * LOCKING:
- * Matching bd_mutex locked or the caller is the only user of @disk.
- */
-static void disk_replace_part_tbl(struct gendisk *disk,
- struct disk_part_tbl *new_ptbl)
-{
- struct disk_part_tbl *old_ptbl =
- rcu_dereference_protected(disk->part_tbl, 1);
-
- rcu_assign_pointer(disk->part_tbl, new_ptbl);
-
- if (old_ptbl) {
- rcu_assign_pointer(old_ptbl->last_lookup, NULL);
- kfree_rcu(old_ptbl, rcu_head);
- }
-}
-
-/**
- * disk_expand_part_tbl - expand disk->part_tbl
- * @disk: disk to expand part_tbl for
- * @partno: expand such that this partno can fit in
- *
- * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
- * uses RCU to allow unlocked dereferencing for stats and other stuff.
- *
- * LOCKING:
- * Matching bd_mutex locked or the caller is the only user of @disk.
- * Might sleep.
- *
- * RETURNS:
- * 0 on success, -errno on failure.
- */
-int disk_expand_part_tbl(struct gendisk *disk, int partno)
-{
- struct disk_part_tbl *old_ptbl =
- rcu_dereference_protected(disk->part_tbl, 1);
- struct disk_part_tbl *new_ptbl;
- int len = old_ptbl ? old_ptbl->len : 0;
- int i, target;
-
- /*
- * check for int overflow, since we can get here from blkpg_ioctl()
- * with a user passed 'partno'.
- */
- target = partno + 1;
- if (target < 0)
- return -EINVAL;
-
- /* disk_max_parts() is zero during initialization, ignore if so */
- if (disk_max_parts(disk) && target > disk_max_parts(disk))
- return -EINVAL;
-
- if (target <= len)
- return 0;
-
- new_ptbl = kzalloc_node(struct_size(new_ptbl, part, target), GFP_KERNEL,
- disk->node_id);
- if (!new_ptbl)
- return -ENOMEM;
-
- new_ptbl->len = target;
-
- for (i = 0; i < len; i++)
- rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
-
- disk_replace_part_tbl(disk, new_ptbl);
- return 0;
-}
-
/**
* disk_release - releases all allocated resources of the gendisk
* @dev: the device representing this disk
blk_free_devt(dev->devt);
disk_release_events(disk);
kfree(disk->random);
- disk_replace_part_tbl(disk, NULL);
+ xa_destroy(&disk->part_tbl);
bdput(disk->part0);
if (disk->queue)
blk_put_queue(disk->queue);
struct gendisk *__alloc_disk_node(int minors, int node_id)
{
struct gendisk *disk;
- struct disk_part_tbl *ptbl;
if (minors > DISK_MAX_PARTS) {
printk(KERN_ERR
goto out_free_disk;
disk->node_id = node_id;
- if (disk_expand_part_tbl(disk, 0))
- goto out_bdput;
-
- ptbl = rcu_dereference_protected(disk->part_tbl, 1);
- rcu_assign_pointer(ptbl->part[0], disk->part0);
+ xa_init(&disk->part_tbl);
+ if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL))
+ goto out_destroy_part_tbl;
disk->minors = minors;
rand_initialize_disk(disk);
device_initialize(disk_to_dev(disk));
return disk;
-out_bdput:
+out_destroy_part_tbl:
+ xa_destroy(&disk->part_tbl);
bdput(disk->part0);
out_free_disk:
kfree(disk);
kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
}
-void set_disk_ro(struct gendisk *disk, int flag)
+/**
+ * set_disk_ro - set a gendisk read-only
+ * @disk: gendisk to operate on
+ * @read_only: %true to set the disk read-only, %false set the disk read/write
+ *
+ * This function is used to indicate whether a given disk device should have its
+ * read-only flag set. set_disk_ro() is typically used by device drivers to
+ * indicate whether the underlying physical device is write-protected.
+ */
+void set_disk_ro(struct gendisk *disk, bool read_only)
{
- struct disk_part_iter piter;
- struct block_device *part;
-
- if (disk->part0->bd_read_only != flag) {
- set_disk_ro_uevent(disk, flag);
- disk->part0->bd_read_only = flag;
+ if (read_only) {
+ if (test_and_set_bit(GD_READ_ONLY, &disk->state))
+ return;
+ } else {
+ if (!test_and_clear_bit(GD_READ_ONLY, &disk->state))
+ return;
}
-
- disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
- while ((part = disk_part_iter_next(&piter)))
- part->bd_read_only = flag;
- disk_part_iter_exit(&piter);
+ set_disk_ro_uevent(disk, read_only);
}
-
EXPORT_SYMBOL(set_disk_ro);
int bdev_read_only(struct block_device *bdev)
{
- if (!bdev)
- return 0;
- return bdev->bd_read_only;
+ return bdev->bd_read_only || get_disk_ro(bdev->bd_disk);
}
-
EXPORT_SYMBOL(bdev_read_only);
/*
projects / linux-2.6-microblaze.git / blobdiff