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Date: Fri, 26 Apr 2019 16:44:40 +0800
From: Chao Yu <yuchao0@...wei.com>
To: Ju Hyung Park <qkrwngud825@...il.com>,
Jaegeuk Kim <jaegeuk@...nel.org>
CC: <linux-f2fs-devel@...ts.sourceforge.net>,
Chao Yu <chao@...nel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [f2fs-dev] [PATCH 2/2] f2fs-tools: relocate chksum_offset for
large_nat_bitmap feature
Hi Ju Hyung,
On 2019/4/24 20:00, Ju Hyung Park wrote:
> Hi Chao and Jaegeuk,
>
> I'm currently unavailable to recompile the kernel and use the new
> layout scheme but I ran the new fsck and attempted to mount it on the
> older kernel.
>
> The used fsck-tools is at f50234c248532528b217efff5861b29fe6ec1b36
> ("f2fs-tools: Fix device zoned model detection").
> fsck still behaves weird, I believe.
>
> The new logs are at
> http://arter97.com/f2fs/f50234c248532528b217efff5861b29fe6ec1b36
>
> The first run spits out 600MB worth of log
> and the second run spits out 60MB worth of log
> and the third run fails to fix "other corrupted bugs".
I found one problem in old fixing patch, could you please try new one?
Thanks,
>
> Runs after the third prints out the same log.
>
> When I try to mount the image after third run on the older kernel, it fails:
> [ 1710.824598] F2FS-fs (loop1): invalid crc value
> [ 1710.855240] F2FS-fs (loop1): SIT is corrupted node# 2174236 vs 2517451
> [ 1710.855243] F2FS-fs (loop1): Failed to initialize F2FS segment manager
>
> I'll report back after I compile and run the kernel with the new
> layout scheme, but I don't feel good about this after fsck printing
> that much logs, and the fact that the 2nd run still spits out a lot of
> logs.
>
> Thanks.
>
> On Mon, Apr 22, 2019 at 6:35 PM Chao Yu <yuchao0@...wei.com> wrote:
>>
>> For large_nat_bitmap feature, there is a design flaw:
>>
>> Previous:
>>
>> struct f2fs_checkpoint layout:
>> +--------------------------+ 0x0000
>> | checkpoint_ver |
>> | ...... |
>> | checksum_offset |------+
>> | ...... | |
>> | sit_nat_version_bitmap[] |<-----|-------+
>> | ...... | | |
>> | checksum_value |<-----+ |
>> +--------------------------+ 0x1000 |
>> | | nat_bitmap + sit_bitmap
>> | payload blocks | |
>> | | |
>> +--------------------------|<-------------+
>>
>> Obviously, if nat_bitmap size + sit_bitmap size is larger than
>> MAX_BITMAP_SIZE_IN_CKPT, nat_bitmap or sit_bitmap may overlap
>> checkpoint checksum's position, once checkpoint() is triggered
>> from kernel, nat or sit bitmap will be damaged by checksum field.
>>
>> In order to fix this, let's relocate checksum_value's position
>> to the head of sit_nat_version_bitmap as below, then nat/sit
>> bitmap and chksum value update will become safe.
>>
>> After:
>>
>> struct f2fs_checkpoint layout:
>> +--------------------------+ 0x0000
>> | checkpoint_ver |
>> | ...... |
>> | checksum_offset |------+
>> | ...... | |
>> | sit_nat_version_bitmap[] |<-----+
>> | ...... |<-------------+
>> | | |
>> +--------------------------+ 0x1000 |
>> | | nat_bitmap + sit_bitmap
>> | payload blocks | |
>> | | |
>> +--------------------------|<-------------+
>>
>> Related report and discussion:
>>
>> https://sourceforge.net/p/linux-f2fs/mailman/message/36642346/
>>
>> In addition, during writing checkpoint, if large_nat_bitmap feature is
>> enabled, we need to set CP_LARGE_NAT_BITMAP_FLAG flag in checkpoint.
>>
>> Reported-by: Park Ju Hyung <qkrwngud825@...il.com>
>> Signed-off-by: Chao Yu <yuchao0@...wei.com>
>> ---
>> fsck/f2fs.h | 6 +++++-
>> fsck/fsck.c | 16 ++++++++++++++++
>> fsck/fsck.h | 1 +
>> fsck/main.c | 2 ++
>> fsck/mount.c | 42 +++++++++++++++++++++++++++---------------
>> include/f2fs_fs.h | 9 +++++++--
>> mkfs/f2fs_format.c | 5 ++++-
>> 7 files changed, 62 insertions(+), 19 deletions(-)
>>
>> diff --git a/fsck/f2fs.h b/fsck/f2fs.h
>> index 93f01e5..6a6c4a5 100644
>> --- a/fsck/f2fs.h
>> +++ b/fsck/f2fs.h
>> @@ -272,7 +272,11 @@ static inline void *__bitmap_ptr(struct f2fs_sb_info *sbi, int flag)
>> if (is_set_ckpt_flags(ckpt, CP_LARGE_NAT_BITMAP_FLAG)) {
>> offset = (flag == SIT_BITMAP) ?
>> le32_to_cpu(ckpt->nat_ver_bitmap_bytesize) : 0;
>> - return &ckpt->sit_nat_version_bitmap + offset;
>> + /*
>> + * if large_nat_bitmap feature is enabled, leave checksum
>> + * protection for all nat/sit bitmaps.
>> + */
>> + return &ckpt->sit_nat_version_bitmap + offset + sizeof(__le32);
>> }
>>
>> if (le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_payload) > 0) {
>> diff --git a/fsck/fsck.c b/fsck/fsck.c
>> index 7ecdee1..8d7deb5 100644
>> --- a/fsck/fsck.c
>> +++ b/fsck/fsck.c
>> @@ -1917,6 +1917,18 @@ int fsck_chk_meta(struct f2fs_sb_info *sbi)
>> return 0;
>> }
>>
>> +void fsck_chk_checkpoint(struct f2fs_sb_info *sbi)
>> +{
>> + struct f2fs_checkpoint *cp = F2FS_CKPT(sbi);
>> +
>> + if (get_cp(ckpt_flags) & CP_LARGE_NAT_BITMAP_FLAG) {
>> + if (get_cp(checksum_offset) != CP_MIN_CHKSUM_OFFSET) {
>> + ASSERT_MSG("Deprecated layout of large_nat_bitmap, "
>> + "chksum_offset:%u", get_cp(checksum_offset));
>> + }
>> + }
>> +}
>> +
>> void fsck_init(struct f2fs_sb_info *sbi)
>> {
>> struct f2fs_fsck *fsck = F2FS_FSCK(sbi);
>> @@ -2038,6 +2050,10 @@ static void fix_checkpoint(struct f2fs_sb_info *sbi)
>> flags |= CP_TRIMMED_FLAG;
>> if (is_set_ckpt_flags(cp, CP_DISABLED_FLAG))
>> flags |= CP_DISABLED_FLAG;
>> + if (is_set_ckpt_flags(cp, CP_LARGE_NAT_BITMAP_FLAG)) {
>> + flags |= CP_LARGE_NAT_BITMAP_FLAG;
>> + set_cp(checksum_offset, CP_MIN_CHKSUM_OFFSET);
>> + }
>>
>> if (flags & CP_UMOUNT_FLAG)
>> cp_blocks = 8;
>> diff --git a/fsck/fsck.h b/fsck/fsck.h
>> index 376ced7..dd831de 100644
>> --- a/fsck/fsck.h
>> +++ b/fsck/fsck.h
>> @@ -154,6 +154,7 @@ extern int fsck_chk_dentry_blk(struct f2fs_sb_info *, u32, struct child_info *,
>> int, int);
>> int fsck_chk_inline_dentries(struct f2fs_sb_info *, struct f2fs_node *,
>> struct child_info *);
>> +void fsck_chk_checkpoint(struct f2fs_sb_info *sbi);
>> int fsck_chk_meta(struct f2fs_sb_info *sbi);
>> int fsck_chk_curseg_info(struct f2fs_sb_info *);
>> int convert_encrypted_name(unsigned char *, u32, unsigned char *, int);
>> diff --git a/fsck/main.c b/fsck/main.c
>> index d3f0c0d..e61bb91 100644
>> --- a/fsck/main.c
>> +++ b/fsck/main.c
>> @@ -616,6 +616,8 @@ static void do_fsck(struct f2fs_sb_info *sbi)
>> c.fix_on = 1;
>> }
>>
>> + fsck_chk_checkpoint(sbi);
>> +
>> fsck_chk_quota_node(sbi);
>>
>> /* Traverse all block recursively from root inode */
>> diff --git a/fsck/mount.c b/fsck/mount.c
>> index da1d4c9..843742e 100644
>> --- a/fsck/mount.c
>> +++ b/fsck/mount.c
>> @@ -769,15 +769,33 @@ int init_sb_info(struct f2fs_sb_info *sbi)
>> return 0;
>> }
>>
>> +static int verify_checksum_chksum(struct f2fs_checkpoint *cp)
>> +{
>> + unsigned int chksum_offset = get_cp(checksum_offset);
>> + unsigned int crc, cal_crc;
>> +
>> + if (chksum_offset < CP_MIN_CHKSUM_OFFSET ||
>> + chksum_offset > CP_CHKSUM_OFFSET) {
>> + MSG(0, "\tInvalid CP CRC offset: %u\n", chksum_offset);
>> + return -1;
>> + }
>> +
>> + crc = le32_to_cpu(*(__le32 *)((unsigned char *)cp + chksum_offset));
>> + cal_crc = f2fs_checkpoint_chksum(cp);
>> + if (cal_crc != crc) {
>> + MSG(0, "\tInvalid CP CRC: offset:%u, crc:0x%x, calc:0x%x\n",
>> + chksum_offset, crc, cal_crc);
>> + return -1;
>> + }
>> + return 0;
>> +}
>> +
>> void *validate_checkpoint(struct f2fs_sb_info *sbi, block_t cp_addr,
>> unsigned long long *version)
>> {
>> void *cp_page_1, *cp_page_2;
>> struct f2fs_checkpoint *cp;
>> - unsigned long blk_size = sbi->blocksize;
>> unsigned long long cur_version = 0, pre_version = 0;
>> - unsigned int crc = 0;
>> - size_t crc_offset;
>>
>> /* Read the 1st cp block in this CP pack */
>> cp_page_1 = malloc(PAGE_SIZE);
>> @@ -787,12 +805,7 @@ void *validate_checkpoint(struct f2fs_sb_info *sbi, block_t cp_addr,
>> goto invalid_cp1;
>>
>> cp = (struct f2fs_checkpoint *)cp_page_1;
>> - crc_offset = get_cp(checksum_offset);
>> - if (crc_offset > (blk_size - sizeof(__le32)))
>> - goto invalid_cp1;
>> -
>> - crc = le32_to_cpu(*(__le32 *)((unsigned char *)cp + crc_offset));
>> - if (f2fs_crc_valid(crc, cp, crc_offset))
>> + if (verify_checksum_chksum(cp))
>> goto invalid_cp1;
>>
>> if (get_cp(cp_pack_total_block_count) > sbi->blocks_per_seg)
>> @@ -810,12 +823,7 @@ void *validate_checkpoint(struct f2fs_sb_info *sbi, block_t cp_addr,
>> goto invalid_cp2;
>>
>> cp = (struct f2fs_checkpoint *)cp_page_2;
>> - crc_offset = get_cp(checksum_offset);
>> - if (crc_offset > (blk_size - sizeof(__le32)))
>> - goto invalid_cp2;
>> -
>> - crc = le32_to_cpu(*(__le32 *)((unsigned char *)cp + crc_offset));
>> - if (f2fs_crc_valid(crc, cp, crc_offset))
>> + if (verify_checksum_chksum(cp))
>> goto invalid_cp2;
>>
>> cur_version = get_cp(checkpoint_ver);
>> @@ -2365,6 +2373,10 @@ void write_checkpoint(struct f2fs_sb_info *sbi)
>> flags |= CP_TRIMMED_FLAG;
>> if (is_set_ckpt_flags(cp, CP_DISABLED_FLAG))
>> flags |= CP_DISABLED_FLAG;
>> + if (is_set_ckpt_flags(cp, CP_LARGE_NAT_BITMAP_FLAG)) {
>> + flags |= CP_LARGE_NAT_BITMAP_FLAG;
>> + set_cp(checksum_offset, CP_MIN_CHKSUM_OFFSET);
>> + }
>>
>> set_cp(free_segment_count, get_free_segments(sbi));
>> set_cp(valid_block_count, sbi->total_valid_block_count);
>> diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
>> index 1bd935c..89b8a0c 100644
>> --- a/include/f2fs_fs.h
>> +++ b/include/f2fs_fs.h
>> @@ -692,10 +692,15 @@ struct f2fs_checkpoint {
>> unsigned char sit_nat_version_bitmap[1];
>> } __attribute__((packed));
>>
>> +#define CP_BITMAP_OFFSET \
>> + (offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
>> +#define CP_MIN_CHKSUM_OFFSET CP_BITMAP_OFFSET
>> +
>> +#define MIN_NAT_BITMAP_SIZE 64
>> #define MAX_SIT_BITMAP_SIZE_IN_CKPT \
>> - (CP_CHKSUM_OFFSET - sizeof(struct f2fs_checkpoint) + 1 - 64)
>> + (CP_CHKSUM_OFFSET - CP_BITMAP_OFFSET - MIN_NAT_BITMAP_SIZE)
>> #define MAX_BITMAP_SIZE_IN_CKPT \
>> - (CP_CHKSUM_OFFSET - sizeof(struct f2fs_checkpoint) + 1)
>> + (CP_CHKSUM_OFFSET - CP_BITMAP_OFFSET)
>>
>> /*
>> * For orphan inode management
>> diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
>> index a534293..eabffce 100644
>> --- a/mkfs/f2fs_format.c
>> +++ b/mkfs/f2fs_format.c
>> @@ -706,7 +706,10 @@ static int f2fs_write_check_point_pack(void)
>> set_cp(nat_ver_bitmap_bytesize, ((get_sb(segment_count_nat) / 2) <<
>> get_sb(log_blocks_per_seg)) / 8);
>>
>> - set_cp(checksum_offset, CP_CHKSUM_OFFSET);
>> + if (c.large_nat_bitmap)
>> + set_cp(checksum_offset, CP_MIN_CHKSUM_OFFSET);
>> + else
>> + set_cp(checksum_offset, CP_CHKSUM_OFFSET);
>>
>> crc = f2fs_checkpoint_chksum(cp);
>> *((__le32 *)((unsigned char *)cp + get_cp(checksum_offset))) =
>> --
>> 2.18.0.rc1
>>
>>
>>
>> _______________________________________________
>> Linux-f2fs-devel mailing list
>> Linux-f2fs-devel@...ts.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
> .
>
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