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Diffstat (limited to 'block/genhd.c')
-rw-r--r--block/genhd.c163
1 files changed, 12 insertions, 151 deletions
diff --git a/block/genhd.c b/block/genhd.c
index 1832add5c738..d3ef29fbc536 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -161,15 +161,6 @@ static void part_in_flight_rw(struct block_device *part,
inflight[1] = 0;
}
-static 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
@@ -204,41 +195,26 @@ void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
*/
struct block_device *disk_part_iter_next(struct disk_part_iter *piter)
{
- struct disk_part_tbl *ptbl;
+ 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);
-
- /* iterate to the next partition */
- for (; piter->idx != ptbl->len; piter->idx += 1) {
- 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->part = bdgrab(part);
if (!piter->part)
continue;
- piter->idx += 1;
+ piter->idx = idx + 1;
break;
}
-
rcu_read_unlock();
return piter->part;
@@ -260,42 +236,6 @@ void disk_part_iter_exit(struct disk_part_iter *piter)
piter->part = NULL;
}
-/**
- * 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.
*
@@ -858,7 +798,7 @@ struct block_device *bdget_disk(struct gendisk *disk, int partno)
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();
@@ -1249,83 +1189,6 @@ static const struct attribute_group *disk_attr_groups[] = {
};
/**
- * 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
*
@@ -1348,7 +1211,7 @@ static void disk_release(struct device *dev)
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);
@@ -1501,7 +1364,6 @@ dev_t blk_lookup_devt(const char *name, int partno)
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
@@ -1519,11 +1381,9 @@ struct gendisk *__alloc_disk_node(int minors, int node_id)
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);
@@ -1532,7 +1392,8 @@ struct gendisk *__alloc_disk_node(int minors, int node_id)
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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-17 05:08:32 +0000