btrfs: pass an ordered_extent to btrfs_submit_compressed_write

btrfs_submit_compressed_write always operates on a single ordered_extent.
Make that explicit by using btrfs_alloc_ordered_extent in the callers
and passing the ordered_extent to btrfs_submit_compressed_write.  This
will help with storing and ordered_extent pointer in the btrfs_bio in
subsequent patches.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/compression.c

@@ -279,33 +279,34 @@ static void btrfs_add_compressed_bio_pages(struct compressed_bio *cb)
  * This also checksums the file bytes and gets things ready for
  * the end io hooks.
  */
-void btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start,
-				 unsigned int len, u64 disk_start,
-				 unsigned int compressed_len,
+void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered,
 				   struct page **compressed_pages,
 				   unsigned int nr_pages,
 				   blk_opf_t write_flags,
 				   bool writeback)
 {
+	struct btrfs_inode *inode = BTRFS_I(ordered->inode);
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	struct compressed_bio *cb;
 
-	ASSERT(IS_ALIGNED(start, fs_info->sectorsize) &&
-	       IS_ALIGNED(len, fs_info->sectorsize));
+	ASSERT(IS_ALIGNED(ordered->file_offset, fs_info->sectorsize));
+	ASSERT(IS_ALIGNED(ordered->num_bytes, fs_info->sectorsize));
 
-	cb = alloc_compressed_bio(inode, start, REQ_OP_WRITE | write_flags,
+	cb = alloc_compressed_bio(inode, ordered->file_offset,
+				  REQ_OP_WRITE | write_flags,
 				  end_compressed_bio_write);
-	cb->start = start;
-	cb->len = len;
+	cb->start = ordered->file_offset;
+	cb->len = ordered->num_bytes;
 	cb->compressed_pages = compressed_pages;
-	cb->compressed_len = compressed_len;
+	cb->compressed_len = ordered->disk_num_bytes;
 	cb->writeback = writeback;
 	INIT_WORK(&cb->write_end_work, btrfs_finish_compressed_write_work);
 	cb->nr_pages = nr_pages;
-	cb->bbio.bio.bi_iter.bi_sector = disk_start >> SECTOR_SHIFT;
+	cb->bbio.bio.bi_iter.bi_sector = ordered->disk_bytenr >> SECTOR_SHIFT;
 	btrfs_add_compressed_bio_pages(cb);
 
 	btrfs_submit_bio(&cb->bbio, 0);
+	btrfs_put_ordered_extent(ordered);
 }
 
 /*

fs/btrfs/compression.h

@@ -10,6 +10,7 @@
 #include "bio.h"
 
 struct btrfs_inode;
+struct btrfs_ordered_extent;
 
 /*
  * We want to make sure that amount of RAM required to uncompress an extent is
@@ -86,9 +87,7 @@ int btrfs_decompress(int type, const u8 *data_in, struct page *dest_page,
 int btrfs_decompress_buf2page(const char *buf, u32 buf_len,
 			      struct compressed_bio *cb, u32 decompressed);
 
-void btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start,
-				  unsigned int len, u64 disk_start,
-				  unsigned int compressed_len,
+void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered,
 				  struct page **compressed_pages,
 				  unsigned int nr_pages,
 				  blk_opf_t write_flags,

fs/btrfs/inode.c

@@ -1182,6 +1182,7 @@ static int submit_one_async_extent(struct btrfs_inode *inode,
 	struct extent_io_tree *io_tree = &inode->io_tree;
 	struct btrfs_root *root = inode->root;
 	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_ordered_extent *ordered;
 	struct btrfs_key ins;
 	struct page *locked_page = NULL;
 	struct extent_map *em;
@@ -1243,7 +1244,7 @@ static int submit_one_async_extent(struct btrfs_inode *inode,
 	}
 	free_extent_map(em);
 
-	ret = btrfs_add_ordered_extent(inode, start,		/* file_offset */
+	ordered = btrfs_alloc_ordered_extent(inode, start,	/* file_offset */
 				       async_extent->ram_size,	/* num_bytes */
 				       async_extent->ram_size,	/* ram_bytes */
 				       ins.objectid,		/* disk_bytenr */
@@ -1251,8 +1252,9 @@ static int submit_one_async_extent(struct btrfs_inode *inode,
 				       0,			/* offset */
 				       1 << BTRFS_ORDERED_COMPRESSED,
 				       async_extent->compress_type);
-	if (ret) {
+	if (IS_ERR(ordered)) {
 		btrfs_drop_extent_map_range(inode, start, end, false);
+		ret = PTR_ERR(ordered);
 		goto out_free_reserve;
 	}
 	btrfs_dec_block_group_reservations(fs_info, ins.objectid);
@@ -1261,11 +1263,7 @@ static int submit_one_async_extent(struct btrfs_inode *inode,
 	extent_clear_unlock_delalloc(inode, start, end,
 			NULL, EXTENT_LOCKED | EXTENT_DELALLOC,
 			PAGE_UNLOCK | PAGE_START_WRITEBACK);
-
-	btrfs_submit_compressed_write(inode, start,	/* file_offset */
-			    async_extent->ram_size,	/* num_bytes */
-			    ins.objectid,		/* disk_bytenr */
-			    ins.offset,			/* compressed_len */
+	btrfs_submit_compressed_write(ordered,
 			    async_extent->pages,	/* compressed_pages */
 			    async_extent->nr_pages,
 			    async_chunk->write_flags, true);
@@ -10274,6 +10272,7 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 	struct extent_io_tree *io_tree = &inode->io_tree;
 	struct extent_changeset *data_reserved = NULL;
 	struct extent_state *cached_state = NULL;
+	struct btrfs_ordered_extent *ordered;
 	int compression;
 	size_t orig_count;
 	u64 start, end;
@@ -10450,14 +10449,15 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 	}
 	free_extent_map(em);
 
-	ret = btrfs_add_ordered_extent(inode, start, num_bytes, ram_bytes,
+	ordered = btrfs_alloc_ordered_extent(inode, start, num_bytes, ram_bytes,
 				       ins.objectid, ins.offset,
 				       encoded->unencoded_offset,
 				       (1 << BTRFS_ORDERED_ENCODED) |
 				       (1 << BTRFS_ORDERED_COMPRESSED),
 				       compression);
-	if (ret) {
+	if (IS_ERR(ordered)) {
 		btrfs_drop_extent_map_range(inode, start, end, false);
+		ret = PTR_ERR(ordered);
 		goto out_free_reserved;
 	}
 	btrfs_dec_block_group_reservations(fs_info, ins.objectid);
@@ -10469,8 +10469,7 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 
 	btrfs_delalloc_release_extents(inode, num_bytes);
 
-	btrfs_submit_compressed_write(inode, start, num_bytes, ins.objectid,
-					  ins.offset, pages, nr_pages, 0, false);
+	btrfs_submit_compressed_write(ordered, pages, nr_pages, 0, false);
 	ret = orig_count;
 	goto out;