Re: [RFC PATCH v5] f2fs: support data compression

[Chao Yu <yuchao0@huawei.com>]

Hi Jaegeuk,

Sorry for the delay.

On 2019/12/19 5:46, Jaegeuk Kim wrote:
> Hi Chao,
> 
> I still see some diffs from my latest testing version, so please check anything
> that you made additionally from here.
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=dev&id=25d18e19a91e60837d36368ee939db13fd16dc64

I've checked the diff and picked up valid parts, could you please check and
comment on it?

---
 fs/f2fs/compress.c |  8 ++++----
 fs/f2fs/data.c     | 18 +++++++++++++++---
 fs/f2fs/f2fs.h     |  3 +++
 fs/f2fs/file.c     |  1 -
 4 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index af23ed6deffd..1bc86a54ad71 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -593,7 +593,7 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 							fgp_flag, GFP_NOFS);
 		if (!page) {
 			ret = -ENOMEM;
-			goto unlock_pages;
+			goto release_pages;
 		}

 		if (PageUptodate(page))
@@ -608,13 +608,13 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 		ret = f2fs_read_multi_pages(cc, &bio, cc->cluster_size,
 						&last_block_in_bio, false);
 		if (ret)
-			goto release_pages;
+			goto unlock_pages;
 		if (bio)
 			f2fs_submit_bio(sbi, bio, DATA);

 		ret = f2fs_init_compress_ctx(cc);
 		if (ret)
-			goto release_pages;
+			goto unlock_pages;
 	}

 	for (i = 0; i < cc->cluster_size; i++) {
@@ -762,7 +762,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 	if (err)
 		goto out_unlock_op;

-	psize = (cc->rpages[last_index]->index + 1) << PAGE_SHIFT;
+	psize = (loff_t)(cc->rpages[last_index]->index + 1) << PAGE_SHIFT;

 	err = f2fs_get_node_info(fio.sbi, dn.nid, &ni);
 	if (err)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 19cd03450066..f1f5c701228d 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -184,13 +184,18 @@ static void f2fs_decompress_work(struct bio_post_read_ctx *ctx)
 }

 #ifdef CONFIG_F2FS_FS_COMPRESSION
+void f2fs_verify_pages(struct page **rpages, unsigned int cluster_size)
+{
+	f2fs_decompress_end_io(rpages, cluster_size, false, true);
+}
+
 static void f2fs_verify_bio(struct bio *bio)
 {
 	struct page *page = bio_first_page_all(bio);
 	struct decompress_io_ctx *dic =
 			(struct decompress_io_ctx *)page_private(page);

-	f2fs_decompress_end_io(dic->rpages, dic->cluster_size, false, true);
+	f2fs_verify_pages(dic->rpages, dic->cluster_size);
 	f2fs_free_dic(dic);
 }
 #endif
@@ -507,10 +512,16 @@ static bool __has_merged_page(struct bio *bio, struct inode *inode,
 	bio_for_each_segment_all(bvec, bio, iter_all) {
 		struct page *target = bvec->bv_page;

-		if (fscrypt_is_bounce_page(target))
+		if (fscrypt_is_bounce_page(target)) {
 			target = fscrypt_pagecache_page(target);
-		if (f2fs_is_compressed_page(target))
+			if (IS_ERR(target))
+				continue;
+		}
+		if (f2fs_is_compressed_page(target)) {
 			target = f2fs_compress_control_page(target);
+			if (IS_ERR(target))
+				continue;
+		}

 		if (inode && inode == target->mapping->host)
 			return true;
@@ -2039,6 +2050,7 @@ int f2fs_read_multi_pages(struct compress_ctx *cc, struct bio **bio_ret,
 	if (ret)
 		goto out;

+	/* cluster was overwritten as normal cluster */
 	if (dn.data_blkaddr != COMPRESS_ADDR)
 		goto out;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 5d55cef66410..17d2af4eeafb 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2719,6 +2719,7 @@ static inline void set_compress_context(struct inode *inode)
 			1 << F2FS_I(inode)->i_log_cluster_size;
 	F2FS_I(inode)->i_flags |= F2FS_COMPR_FL;
 	set_inode_flag(inode, FI_COMPRESSED_FILE);
+	stat_inc_compr_inode(inode);
 }

 static inline unsigned int addrs_per_inode(struct inode *inode)
@@ -3961,6 +3962,8 @@ static inline bool f2fs_force_buffered_io(struct inode *inode,
 		return true;
 	if (f2fs_is_multi_device(sbi))
 		return true;
+	if (f2fs_compressed_file(inode))
+		return true;
 	/*
 	 * for blkzoned device, fallback direct IO to buffered IO, so
 	 * all IOs can be serialized by log-structured write.
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index bde5612f37f5..9aeadf14413c 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1828,7 +1828,6 @@ static int f2fs_setflags_common(struct inode *inode, u32 iflags, u32 mask)
 				return -EINVAL;

 			set_compress_context(inode);
-			stat_inc_compr_inode(inode);
 		}
 	}
 	if ((iflags ^ fi->i_flags) & F2FS_NOCOMP_FL) {
-- 
2.18.0.rc1

Thanks,