Hi,
在 2024/02/26 18:29, Christoph Hellwig 写道:
Add a few helpers that wrap the block queue limits API for use in MD.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/md/md.c | 37 +++++++++++++++++++++++++++++++++++++
drivers/md/md.h | 3 +++
2 files changed, 40 insertions(+)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 75266c34b1f99b..23823823f80c6b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5699,6 +5699,43 @@ static const struct kobj_type md_ktype = {
int mdp_major = 0;
+/* stack the limit for all rdevs into lim */
+void mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim)
+{
+ struct md_rdev *rdev;
+
+ rdev_for_each(rdev, mddev) {
+ queue_limits_stack_bdev(lim, rdev->bdev, rdev->data_offset,
+ mddev->gendisk->disk_name);
+ }
+}
+EXPORT_SYMBOL_GPL(mddev_stack_rdev_limits);
+
+/* apply the extra stacking limits from a new rdev into mddev */
+int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev)
+{
+ struct queue_limits lim = queue_limits_start_update(mddev->queue);
+
+ queue_limits_stack_bdev(&lim, rdev->bdev, rdev->data_offset,
+ mddev->gendisk->disk_name);
+ return queue_limits_commit_update(mddev->queue, &lim);
+}
+EXPORT_SYMBOL_GPL(mddev_stack_new_rdev);
+
+/* update the optimal I/O size after a reshape */
+void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes)
+{
+ struct queue_limits lim;
+ int ret;
+
+ blk_mq_freeze_queue(mddev->queue);
+ lim = queue_limits_start_update(mddev->queue);
+ lim.io_opt = lim.io_min * nr_stripes;
+ ret = queue_limits_commit_update(mddev->queue, &lim);
+ blk_mq_unfreeze_queue(mddev->queue);
Any reason to use blk_mq_freeze/unfreeze_queue ? I don't think this is
meaningful for raid, this only wait for IO submission, not IO done.
raid should already handle concurrent IO with reshape, so I think this
can just be removed.
Thanks,
Kuai
+}
+EXPORT_SYMBOL_GPL(mddev_update_io_opt);
+
static void mddev_delayed_delete(struct work_struct *ws)
{
struct mddev *mddev = container_of(ws, struct mddev, del_work);
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 8d881cc597992f..25b19614aa3239 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -860,6 +860,9 @@ void md_autostart_arrays(int part);
int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
int do_md_run(struct mddev *mddev);
+void mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim);
+int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev);
+void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes);
extern const struct block_device_operations md_fops;
