btrfs: compression: migrate compression/decompression paths to folios

For both compression and decompression paths, we always require a
"struct page **pages" and "unsigned long nr_pages", this involves quite
some part of the btrfs compression paths:

- All the compression entry points

- compressed_bio structure
  This affects both compression and decompression.

- async_extent structure

Unfortunately with all those involved parts, there is no good way to
split the conversion into smaller patches while still passing compiling.
So do this in one big conversion in one go.

Please note this is direct page->folio conversion, no change on the page
sized folio requirement yet.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor style fixups ]
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 18 insertions, 21 deletions

diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index 2673c25415e5..c20c1a1b09d5 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -41,11 +41,11 @@ static_assert((BTRFS_MAX_COMPRESSED % PAGE_SIZE) == 0);
 #define	BTRFS_ZLIB_DEFAULT_LEVEL		3
 
 struct compressed_bio {
-	/* Number of compressed pages in the array */
-	unsigned int nr_pages;
+	/* Number of compressed folios in the array. */
+	unsigned int nr_folios;
 
-	/* the pages with the compressed data on them */
-	struct page **compressed_pages;
+	/* The folios with the compressed data on them. */
+	struct folio **compressed_folios;
 
 	/* starting offset in the inode for our pages */
 	u64 start;
@@ -85,21 +85,18 @@ static inline unsigned int btrfs_compress_level(unsigned int type_level)
 int __init btrfs_init_compress(void);
 void __cold btrfs_exit_compress(void);
 
-int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping,
-			 u64 start, struct page **pages,
-			 unsigned long *out_pages,
-			 unsigned long *total_in,
-			 unsigned long *total_out);
+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,
 		     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);
 
 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 folio **compressed_folios,
+				   unsigned int nr_folios, blk_opf_t write_flags,
+				   bool writeback);
 void btrfs_submit_compressed_read(struct btrfs_bio *bbio);
 
 unsigned int btrfs_compress_str2level(unsigned int type, const char *str);
@@ -149,11 +146,11 @@ bool btrfs_compress_is_valid_type(const char *str, size_t len);
 
 int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end);
 
-int btrfs_compress_find_get_page(struct address_space *mapping, u64 start,
-				 struct page **in_page_ret);
+int btrfs_compress_filemap_get_folio(struct address_space *mapping, u64 start,
+				     struct folio **in_folio_ret);
 
-int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
-		u64 start, struct page **pages, unsigned long *out_pages,
+int zlib_compress_folios(struct list_head *ws, struct address_space *mapping,
+			 u64 start, struct folio **folios, unsigned long *out_folios,
 		unsigned long *total_in, unsigned long *total_out);
 int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
 int zlib_decompress(struct list_head *ws, const u8 *data_in,
@@ -163,8 +160,8 @@ struct list_head *zlib_alloc_workspace(unsigned int level);
 void zlib_free_workspace(struct list_head *ws);
 struct list_head *zlib_get_workspace(unsigned int level);
 
-int lzo_compress_pages(struct list_head *ws, struct address_space *mapping,
-		u64 start, struct page **pages, unsigned long *out_pages,
+int lzo_compress_folios(struct list_head *ws, struct address_space *mapping,
+			u64 start, struct folio **folios, unsigned long *out_folios,
 		unsigned long *total_in, unsigned long *total_out);
 int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
 int lzo_decompress(struct list_head *ws, const u8 *data_in,
@@ -173,8 +170,8 @@ int lzo_decompress(struct list_head *ws, const u8 *data_in,
 struct list_head *lzo_alloc_workspace(unsigned int level);
 void lzo_free_workspace(struct list_head *ws);
 
-int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
-		u64 start, struct page **pages, unsigned long *out_pages,
+int zstd_compress_folios(struct list_head *ws, struct address_space *mapping,
+			 u64 start, struct folio **folios, unsigned long *out_folios,
 		unsigned long *total_in, unsigned long *total_out);
 int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb);
 int zstd_decompress(struct list_head *ws, const u8 *data_in,