[dm-devel] [dm-6.4 PATCH v3 01/20] dm bufio: remove unused dm_bufio_release_move interface

Mike Snitzer
2023-03-27T20:13:26Z

From: Joe Thornber <ejt@redhat.com>

Was used by multi-snapshot DM target that never went upstream.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
---
drivers/md/dm-bufio.c | 77 ----------------------------------------
include/linux/dm-bufio.h | 6 ----
2 files changed, 83 deletions(-)

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index cf077f9b30c3..79434b38f368 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -1415,83 +1415,6 @@ int dm_bufio_issue_discard(struct dm_bufio_client *c, sector_t block, sector_t c
}
EXPORT_SYMBOL_GPL(dm_bufio_issue_discard);

-/*
- * We first delete any other buffer that may be at that new location.
- *
- * Then, we write the buffer to the original location if it was dirty.
- *
- * Then, if we are the only one who is holding the buffer, relink the buffer
- * in the buffer tree for the new location.
- *
- * If there was someone else holding the buffer, we write it to the new
- * location but not relink it, because that other user needs to have the buffer
- * at the same place.
- */
-void dm_bufio_release_move(struct dm_buffer *b, sector_t new_block)
-{
- struct dm_bufio_client *c = b->c;
- struct dm_buffer *new;
-
- BUG_ON(dm_bufio_in_request());
-
- dm_bufio_lock(c);
-
-retry:
- new = __find(c, new_block);
- if (new) {
- if (new->hold_count) {
- __wait_for_free_buffer(c);
- goto retry;
- }
-
- /*
- * FIXME: Is there any point waiting for a write that's going
- * to be overwritten in a bit?
- */
- __make_buffer_clean(new);
- __unlink_buffer(new);
- __free_buffer_wake(new);
- }
-
- BUG_ON(!b->hold_count);
- BUG_ON(test_bit(B_READING, &b->state));
-
- __write_dirty_buffer(b, NULL);
- if (b->hold_count == 1) {
- wait_on_bit_io(&b->state, B_WRITING,
- TASK_UNINTERRUPTIBLE);
- set_bit(B_DIRTY, &b->state);
- b->dirty_start = 0;
- b->dirty_end = c->block_size;
- __unlink_buffer(b);
- __link_buffer(b, new_block, LIST_DIRTY);
- } else {
- sector_t old_block;
-
- wait_on_bit_lock_io(&b->state, B_WRITING,
- TASK_UNINTERRUPTIBLE);
- /*
- * Relink buffer to "new_block" so that write_callback
- * sees "new_block" as a block number.
- * After the write, link the buffer back to old_block.
- * All this must be done in bufio lock, so that block number
- * change isn't visible to other threads.
- */
- old_block = b->block;
- __unlink_buffer(b);
- __link_buffer(b, new_block, b->list_mode);
- submit_io(b, REQ_OP_WRITE, write_endio);
- wait_on_bit_io(&b->state, B_WRITING,
- TASK_UNINTERRUPTIBLE);
- __unlink_buffer(b);
- __link_buffer(b, old_block, b->list_mode);
- }
-
- dm_bufio_unlock(c);
- dm_bufio_release(b);
-}
-EXPORT_SYMBOL_GPL(dm_bufio_release_move);
-
static void forget_buffer_locked(struct dm_buffer *b)
{
if (likely(!b->hold_count) && likely(!smp_load_acquire(&b->state))) {
diff --git a/include/linux/dm-bufio.h b/include/linux/dm-bufio.h
index 2056743aaaaa..681656a1c03d 100644
--- a/include/linux/dm-bufio.h
+++ b/include/linux/dm-bufio.h
@@ -130,12 +130,6 @@ int dm_bufio_issue_flush(struct dm_bufio_client *c);
*/
int dm_bufio_issue_discard(struct dm_bufio_client *c, sector_t block, sector_t count);

-/*
- * Like dm_bufio_release but also move the buffer to the new
- * block. dm_bufio_write_dirty_buffers is needed to commit the new block.
- */
-void dm_bufio_release_move(struct dm_buffer *b, sector_t new_block);
-
/*
* Free the given buffer.
* This is just a hint, if the buffer is in use or dirty, this function