btrfs: convert btrfs_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. Based on the previous patch, the compression path can be
directly used in folio without converting to page.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/compression.c

@@ -138,15 +138,15 @@ static int compression_decompress_bio(struct list_head *ws,
 }
 
 static int compression_decompress(int type, struct list_head *ws,
-		const u8 *data_in, struct page *dest_page,
+		const u8 *data_in, struct folio *dest_folio,
 		unsigned long dest_pgoff, size_t srclen, size_t destlen)
 {
 	switch (type) {
-	case BTRFS_COMPRESS_ZLIB: return zlib_decompress(ws, data_in, page_folio(dest_page),
+	case BTRFS_COMPRESS_ZLIB: return zlib_decompress(ws, data_in, dest_folio,
 						dest_pgoff, srclen, destlen);
-	case BTRFS_COMPRESS_LZO:  return lzo_decompress(ws, data_in, page_folio(dest_page),
+	case BTRFS_COMPRESS_LZO:  return lzo_decompress(ws, data_in, dest_folio,
 						dest_pgoff, srclen, destlen);
-	case BTRFS_COMPRESS_ZSTD: return zstd_decompress(ws, data_in, page_folio(dest_page),
+	case BTRFS_COMPRESS_ZSTD: return zstd_decompress(ws, data_in, dest_folio,
 						dest_pgoff, srclen, destlen);
 	case BTRFS_COMPRESS_NONE:
 	default:
@@ -1061,10 +1061,10 @@ static int btrfs_decompress_bio(struct compressed_bio *cb)
  * single page, and we want to read a single page out of it.
  * start_byte tells us the offset into the compressed data we're interested in
  */
-int btrfs_decompress(int type, const u8 *data_in, struct page *dest_page,
+int btrfs_decompress(int type, const u8 *data_in, struct folio *dest_folio,
 		     unsigned long dest_pgoff, size_t srclen, size_t destlen)
 {
-	struct btrfs_fs_info *fs_info = page_to_fs_info(dest_page);
+	struct btrfs_fs_info *fs_info = folio_to_fs_info(dest_folio);
 	struct list_head *workspace;
 	const u32 sectorsize = fs_info->sectorsize;
 	int ret;
@@ -1077,7 +1077,7 @@ int btrfs_decompress(int type, const u8 *data_in, struct page *dest_page,
 	ASSERT(dest_pgoff + destlen <= PAGE_SIZE && destlen <= sectorsize);
 
 	workspace = get_workspace(type, 0);
-	ret = compression_decompress(type, workspace, data_in, dest_page,
+	ret = compression_decompress(type, workspace, data_in, dest_folio,
 				     dest_pgoff, srclen, destlen);
 	put_workspace(type, workspace);
 

fs/btrfs/compression.h

@@ -96,7 +96,7 @@ void __cold btrfs_exit_compress(void);
 int btrfs_compress_folios(unsigned int type_level, struct address_space *mapping,
 			  u64 start, struct folio **folios, unsigned long *out_folios,
 			 unsigned long *total_in, unsigned long *total_out);
-int btrfs_decompress(int type, const u8 *data_in, struct page *dest_page,
+int btrfs_decompress(int type, const u8 *data_in, struct folio *dest_folio,
 		     unsigned long start_byte, size_t srclen, size_t destlen);
 int btrfs_decompress_buf2page(const char *buf, u32 buf_len,
 			      struct compressed_bio *cb, u32 decompressed);

fs/btrfs/inode.c

@@ -6746,7 +6746,7 @@ static noinline int uncompress_inline(struct btrfs_path *path,
 	read_extent_buffer(leaf, tmp, ptr, inline_size);
 
 	max_size = min_t(unsigned long, PAGE_SIZE, max_size);
-	ret = btrfs_decompress(compress_type, tmp, &folio->page, 0, inline_size,
+	ret = btrfs_decompress(compress_type, tmp, folio, 0, inline_size,
 			       max_size);
 
 	/*

fs/btrfs/reflink.c

@@ -118,7 +118,7 @@ static int copy_inline_to_page(struct btrfs_inode *inode,
 		memcpy_to_page(page, offset_in_page(file_offset), data_start,
 			       datal);
 	} else {
-		ret = btrfs_decompress(comp_type, data_start, page,
+		ret = btrfs_decompress(comp_type, data_start, page_folio(page),
 				       offset_in_page(file_offset),
 				       inline_size, datal);
 		if (ret)