fs/buffer: remove ll_rw_block() helper

Bugzilla: https://bugzilla.redhat.com/2160719
Tested: xfstests
Upstream Status: upstream

commit 79f5978
Author: Zhang Yi <yi.zhang@huawei.com>
    
    Now that all ll_rw_block() users has been replaced to new safe helpers,
    we just remove it here.
    
    Link: https://lkml.kernel.org/r/20220901133505.2510834-13-yi.zhang@huawei.com
    Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
    Reviewed-by: Jan Kara <jack@suse.cz>
    Reviewed-by: Christoph Hellwig <hch@lst.de>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    (cherry picked from commit 79f5978)

Signed-off-by: Lukas Czerner <lczerner@redhat.com>

Author: Lukas Czerner

fs/buffer.c

@@ -152,7 +152,7 @@ static void __end_buffer_read_notouch(struct buffer_head *bh, int uptodate)
 
 /*
  * Default synchronous end-of-IO handler..  Just mark it up-to-date and
- * unlock the buffer. This is what ll_rw_block uses too.
+ * unlock the buffer.
  */
 void end_buffer_read_sync(struct buffer_head *bh, int uptodate)
 {
@@ -491,8 +491,8 @@ int inode_has_buffers(struct inode *inode)
  * all already-submitted IO to complete, but does not queue any new
  * writes to the disk.
  *
- * To do O_SYNC writes, just queue the buffer writes with ll_rw_block as
- * you dirty the buffers, and then use osync_inode_buffers to wait for
+ * To do O_SYNC writes, just queue the buffer writes with write_dirty_buffer
+ * as you dirty the buffers, and then use osync_inode_buffers to wait for
  * completion.  Any other dirty buffers which are not yet queued for
  * write will not be flushed to disk by the osync.
  */
@@ -1806,7 +1806,7 @@ int __block_write_full_page(struct inode *inode, struct page *page,
 		/*
 		 * The page was marked dirty, but the buffers were
 		 * clean.  Someone wrote them back by hand with
-		 * ll_rw_block/submit_bh.  A rare case.
+		 * write_dirty_buffer/submit_bh.  A rare case.
 		 */
 		end_page_writeback(page);
 
@@ -3040,61 +3040,6 @@ int submit_bh(blk_opf_t opf, struct buffer_head *bh)
 }
 EXPORT_SYMBOL(submit_bh);
 
-/**
- * ll_rw_block: low-level access to block devices (DEPRECATED)
- * @opf: block layer request operation and flags.
- * @nr: number of &struct buffer_heads in the array
- * @bhs: array of pointers to &struct buffer_head
- *
- * ll_rw_block() takes an array of pointers to &struct buffer_heads, and
- * requests an I/O operation on them, either a %REQ_OP_READ or a %REQ_OP_WRITE.
- * @opf contains flags modifying the detailed I/O behavior, most notably
- * %REQ_RAHEAD.
- *
- * This function drops any buffer that it cannot get a lock on (with the
- * BH_Lock state bit), any buffer that appears to be clean when doing a write
- * request, and any buffer that appears to be up-to-date when doing read
- * request.  Further it marks as clean buffers that are processed for
- * writing (the buffer cache won't assume that they are actually clean
- * until the buffer gets unlocked).
- *
- * ll_rw_block sets b_end_io to simple completion handler that marks
- * the buffer up-to-date (if appropriate), unlocks the buffer and wakes
- * any waiters. 
- *
- * All of the buffers must be for the same device, and must also be a
- * multiple of the current approved size for the device.
- */
-void ll_rw_block(const blk_opf_t opf, int nr, struct buffer_head *bhs[])
-{
-	const enum req_op op = opf & REQ_OP_MASK;
-	int i;
-
-	for (i = 0; i < nr; i++) {
-		struct buffer_head *bh = bhs[i];
-
-		if (!trylock_buffer(bh))
-			continue;
-		if (op == REQ_OP_WRITE) {
-			if (test_clear_buffer_dirty(bh)) {
-				bh->b_end_io = end_buffer_write_sync;
-				get_bh(bh);
-				submit_bh(opf, bh);
-				continue;
-			}
-		} else {
-			if (!buffer_uptodate(bh)) {
-				bh->b_end_io = end_buffer_read_sync;
-				get_bh(bh);
-				submit_bh(opf, bh);
-				continue;
-			}
-		}
-		unlock_buffer(bh);
-	}
-}
-EXPORT_SYMBOL(ll_rw_block);
-
 void write_dirty_buffer(struct buffer_head *bh, blk_opf_t op_flags)
 {
 	lock_buffer(bh);

include/linux/buffer_head.h

@@ -223,7 +223,6 @@ struct buffer_head *alloc_buffer_head(gfp_t gfp_flags);
 void free_buffer_head(struct buffer_head * bh);
 void unlock_buffer(struct buffer_head *bh);
 void __lock_buffer(struct buffer_head *bh);
-void ll_rw_block(blk_opf_t, int, struct buffer_head * bh[]);
 int sync_dirty_buffer(struct buffer_head *bh);
 int __sync_dirty_buffer(struct buffer_head *bh, blk_opf_t op_flags);
 void write_dirty_buffer(struct buffer_head *bh, blk_opf_t op_flags);