Commit ea1db795 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

ublk: refactor common helper ublk_shmem_remove_ranges() 



Extract the shared walk+erase+unpin+kfree loop into
ublk_shmem_remove_ranges(). When buf_index >= 0, only ranges matching
that index are removed; when buf_index < 0, all ranges are removed.

Also extract ublk_unpin_range_pages() to share the page unpinning
loop.

Convert both __ublk_ctrl_unreg_buf() and ublk_buf_cleanup() to use
the new helper.

Signed-off-by: default avatarMing Lei <tom.leiming@gmail.com>
Link: https://patch.msgid.link/20260423033058.2805135-3-tom.leiming@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 47903faa

drivers/block/ublk_drv.c

+29 −40
Original line number Diff line number Diff line
@@ -5421,18 +5421,40 @@ static int ublk_ctrl_reg_buf(struct ublk_device *ub, 
	return ret;

}



static int __ublk_ctrl_unreg_buf(struct ublk_device *ub, int buf_index)

static void ublk_unpin_range_pages(unsigned long base_pfn,

				   unsigned long nr_pages)

{

#define UBLK_UNPIN_BATCH	32

	struct page *pages[UBLK_UNPIN_BATCH];

	unsigned long off;



	for (off = 0; off < nr_pages; ) {

		unsigned int batch = min_t(unsigned long,

					   nr_pages - off, UBLK_UNPIN_BATCH);

		unsigned int j;



		for (j = 0; j < batch; j++)

			pages[j] = pfn_to_page(base_pfn + off + j);

		unpin_user_pages(pages, batch);

		off += batch;

	}

}



/*

 * Remove ranges from the maple tree matching buf_index, unpin pages

 * and free range structs. If buf_index < 0, remove all ranges.

 */

static int ublk_shmem_remove_ranges(struct ublk_device *ub, int buf_index)

{

	MA_STATE(mas, &ub->buf_tree, 0, ULONG_MAX);

	struct ublk_buf_range *range;

	struct page *pages[32];

	int ret = -ENOENT;



	mas_lock(&mas);

	mas_for_each(&mas, range, ULONG_MAX) {

		unsigned long base, nr, off;

		unsigned long base, nr;



		if (range->buf_index != buf_index)

		if (buf_index >= 0 && range->buf_index != buf_index)

			continue;



		ret = 0;
@@ -5440,16 +5462,7 @@ static int __ublk_ctrl_unreg_buf(struct ublk_device *ub, int buf_index) 
		nr = mas.last - base + 1;

		mas_erase(&mas);



		for (off = 0; off < nr; ) {

			unsigned int batch = min_t(unsigned long,

						   nr - off, 32);

			unsigned int j;



			for (j = 0; j < batch; j++)

				pages[j] = pfn_to_page(base + off + j);

			unpin_user_pages(pages, batch);

			off += batch;

		}

		ublk_unpin_range_pages(base, nr);

		kfree(range);

	}

	mas_unlock(&mas);
@@ -5472,7 +5485,7 @@ static int ublk_ctrl_unreg_buf(struct ublk_device *ub, 


	memflags = ublk_lock_buf_tree(ub);



	ret = __ublk_ctrl_unreg_buf(ub, index);

	ret = ublk_shmem_remove_ranges(ub, index);

	if (!ret)

		ida_free(&ub->buf_ida, index);
@@ -5482,31 +5495,7 @@ static int ublk_ctrl_unreg_buf(struct ublk_device *ub, 


static void ublk_buf_cleanup(struct ublk_device *ub)

{

	MA_STATE(mas, &ub->buf_tree, 0, ULONG_MAX);

	struct ublk_buf_range *range;

	struct page *pages[32];



	mas_lock(&mas);

	mas_for_each(&mas, range, ULONG_MAX) {

		unsigned long base = mas.index;

		unsigned long nr = mas.last - base + 1;

		unsigned long off;



		mas_erase(&mas);



		for (off = 0; off < nr; ) {

			unsigned int batch = min_t(unsigned long,

						   nr - off, 32);

			unsigned int j;



			for (j = 0; j < batch; j++)

				pages[j] = pfn_to_page(base + off + j);

			unpin_user_pages(pages, batch);

			off += batch;

		}

		kfree(range);

	}

	mas_unlock(&mas);

	ublk_shmem_remove_ranges(ub, -1);

	mtree_destroy(&ub->buf_tree);

	ida_destroy(&ub->buf_ida);

}