Re: [PATCH v4] f2fs: introduce get_checkpoint_version for cleanup

["Tiezhu Yang" <kernelpatch@126.com>]

At 2016-09-30 07:47:58, "Tiezhu Yang" <kernelpatch@126.com> wrote:
>There exists almost same codes when get the value of pre_version
>and cur_version in function validate_checkpoint, this patch adds
>get_checkpoint_version to clean up redundant codes.
>
>Signed-off-by: Tiezhu Yang <kernelpatch@126.com>
>---
> fs/f2fs/checkpoint.c | 66 ++++++++++++++++++++++++++++++----------------------
> 1 file changed, 38 insertions(+), 28 deletions(-)
>
>diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
>index de8693c..764ed0b 100644
>--- a/fs/f2fs/checkpoint.c
>+++ b/fs/f2fs/checkpoint.c
>@@ -663,45 +663,55 @@ static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
> 	}
> }
> 
>-static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
>-				block_t cp_addr, unsigned long long *version)
>+static int get_checkpoint_version(struct f2fs_sb_info *sbi, block_t cp_addr,
>+		struct f2fs_checkpoint **cp_block, struct page **cp_page,
>+		unsigned long long *version)
> {
>-	struct page *cp_page_1, *cp_page_2 = NULL;
> 	unsigned long blk_size = sbi->blocksize;
>-	struct f2fs_checkpoint *cp_block;
>-	unsigned long long cur_version = 0, pre_version = 0;
>-	size_t crc_offset;
>+	size_t crc_offset = 0;
> 	__u32 crc = 0;
> 
>-	/* Read the 1st cp block in this CP pack */
>-	cp_page_1 = get_meta_page(sbi, cp_addr);
>+	*cp_page = get_meta_page(sbi, cp_addr);
>+	*cp_block = (struct f2fs_checkpoint *)page_address(*cp_page);
> 
>-	/* get the version number */
>-	cp_block = (struct f2fs_checkpoint *)page_address(cp_page_1);
>-	crc_offset = le32_to_cpu(cp_block->checksum_offset);
>-	if (crc_offset >= blk_size)
>-		goto invalid_cp1;
>+	crc_offset = le32_to_cpu((*cp_block)->checksum_offset);
>+	if (crc_offset >= blk_size) {
>+		f2fs_msg(sbi->sb, KERN_WARNING,
>+			"invalid crc_offset: %zu.", crc_offset);

Sorry, The full stop '.' is needless, I will resend it.

Thanks,
>+		return -EINVAL;
>+	}
> 
>-	crc = le32_to_cpu(*((__le32 *)((unsigned char *)cp_block + crc_offset)));
>-	if (!f2fs_crc_valid(sbi, crc, cp_block, crc_offset))
>-		goto invalid_cp1;
>+	crc = le32_to_cpu(*((__le32 *)((unsigned char *)*cp_block
>+							+ crc_offset)));
>+	if (!f2fs_crc_valid(sbi, crc, *cp_block, crc_offset)) {
>+		f2fs_msg(sbi->sb, KERN_WARNING, "invalid crc value.");

ditto

>+		return -EINVAL;
>+	}
> 
>-	pre_version = cur_cp_version(cp_block);
>+	*version = cur_cp_version(*cp_block);
>+	return 0;
>+}
> 
>-	/* Read the 2nd cp block in this CP pack */
>-	cp_addr += le32_to_cpu(cp_block->cp_pack_total_block_count) - 1;
>-	cp_page_2 = get_meta_page(sbi, cp_addr);
>+static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
>+				block_t cp_addr, unsigned long long *version)
>+{
>+	struct page *cp_page_1 = NULL, *cp_page_2 = NULL;
>+	struct f2fs_checkpoint *cp_block = NULL;
>+	unsigned long long cur_version = 0, pre_version = 0;
>+	int err;
> 
>-	cp_block = (struct f2fs_checkpoint *)page_address(cp_page_2);
>-	crc_offset = le32_to_cpu(cp_block->checksum_offset);
>-	if (crc_offset >= blk_size)
>-		goto invalid_cp2;
>+	err = get_checkpoint_version(sbi, cp_addr, &cp_block,
>+					&cp_page_1, version);
>+	if (err)
>+		goto invalid_cp1;
>+	pre_version = *version;
> 
>-	crc = le32_to_cpu(*((__le32 *)((unsigned char *)cp_block + crc_offset)));
>-	if (!f2fs_crc_valid(sbi, crc, cp_block, crc_offset))
>+	cp_addr += le32_to_cpu(cp_block->cp_pack_total_block_count) - 1;
>+	err = get_checkpoint_version(sbi, cp_addr, &cp_block,
>+					&cp_page_2, version);
>+	if (err)
> 		goto invalid_cp2;
>-
>-	cur_version = cur_cp_version(cp_block);
>+	cur_version = *version;
> 
> 	if (cur_version == pre_version) {
> 		*version = cur_version;
>-- 
>1.8.3.1
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