From 55e07d6dd155269d4b8b8bdcb03716ca5df815cb Mon Sep 17 00:00:00 2001
Date: Tue, 29 Mar 2022 11:50:39 +0200
Subject: [PATCH] fs/btrfs: Allow for a per-extent compression level

---
 fs/btrfs/inode.c           | 34 ++++++++++++++++++++++++----------
 fs/btrfs/ioctl.c           |  6 +++++-
 include/uapi/linux/btrfs.h |  9 ++++++++-
 3 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index aa0a60ee26cb..9f751076a00e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -597,6 +597,7 @@ static noinline int compress_file_range(struct async_chunk *async_chunk)
 	int i;
 	int will_compress;
 	int compress_type = fs_info->compress_type;
+	int compress_level = 0;
 	int compressed_extents = 0;
 	int redirty = 0;

@@ -675,8 +676,10 @@ static noinline int compress_file_range(struct async_chunk *async_chunk)
 			goto cont;
 		}

-		if (BTRFS_I(inode)->defrag_compress)
-			compress_type = BTRFS_I(inode)->defrag_compress;
+		if (BTRFS_I(inode)->defrag_compress){
+			compress_type = BTRFS_I(inode)->defrag_compress & 0xF;
+			compress_level = BTRFS_I(inode)->defrag_compress >> 4;
+		}
 		else if (BTRFS_I(inode)->prop_compress)
 			compress_type = BTRFS_I(inode)->prop_compress;

@@ -697,14 +700,25 @@ static noinline int compress_file_range(struct async_chunk *async_chunk)
 			redirty = 1;
 		}

-		/* Compression level is applied here and only here */
-		ret = btrfs_compress_pages(
-			compress_type | (fs_info->compress_level << 4),
-					   inode->i_mapping, start,
-					   pages,
-					   &nr_pages,
-					   &total_in,
-					   &total_compressed);
+		/* Compression level is applied here and only here
+		 * Takes the compression level from the inode, if set
+		 */
+		if (compress_level)
+			ret = btrfs_compress_pages(
+				compress_type | compress_level << 4,
+				inode->i_mapping, start,
+				pages,
+				&nr_pages,
+				&total_in,
+				&total_compressed);
+		else
+			ret = btrfs_compress_pages(
+				compress_type | fs_info->compress_level << 4,
+				inode->i_mapping, start,
+				pages,
+				&nr_pages,
+				&total_in,
+				&total_compressed);

 		if (!ret) {
 			unsigned long offset = offset_in_page(total_compressed);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 238cee5b5254..7534e13c487d 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1777,6 +1777,7 @@ int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
 	bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
 	bool ra_allocated = false;
 	int compress_type = BTRFS_COMPRESS_ZLIB;
+	int compress_level = 0;
 	int ret = 0;
 	u32 extent_thresh = range->extent_thresh;
 	pgoff_t start_index;
@@ -1792,6 +1793,8 @@ int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
 			return -EINVAL;
 		if (range->compress_type)
 			compress_type = range->compress_type;
+		if (range->compress_level)
+			compress_level = range->compress_level;
 	}

 	if (extent_thresh == 0)
@@ -1855,7 +1858,8 @@ int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
 			break;
 		}
 		if (do_compress)
-			BTRFS_I(inode)->defrag_compress = compress_type;
+			BTRFS_I(inode)->defrag_compress = compress_type |
+							  compress_level << 4;
 		ret = defrag_one_cluster(BTRFS_I(inode), ra, cur,
 				cluster_end + 1 - cur, extent_thresh,
 				newer_than, do_compress, &sectors_defragged,
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index d956b2993970..b330d0896a5a 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -605,8 +605,15 @@ struct btrfs_ioctl_defrag_range_args {
 	 */
 	__u32 compress_type;

+	/*
+	 * which compression strength to use if turning on compression
+	 * for this defrag operation.  If unspecified, the inode's value
+	 * will be used
+	 */
+	__u32 compress_level;
+
 	/* spare for later */
-	__u32 unused[4];
+	__u32 unused[3];
 };


--
2.30.2