From: Chao Yu via Linux-f2fs-devel <linux-f2fs-devel@lists.sourceforge.net>
To: Daeho Jeong <daeho43@gmail.com>
Cc: Daeho Jeong <daehojeong@google.com>,
kernel-team@android.com, linux-kernel@vger.kernel.org,
linux-f2fs-devel@lists.sourceforge.net
Subject: Re: [f2fs-dev] [PATCH v5] f2fs-tools: revert summary entry count from 2048 to 512 in 16kb block support
Date: Tue, 23 Dec 2025 10:33:59 +0800 [thread overview]
Message-ID: <04a4dcd6-e8cb-4378-bf79-e4e90af17e87@kernel.org> (raw)
In-Reply-To: <CACOAw_z+uTang-h44ROsKU5vxVZGUE7UJR2TF9zYdg5OXB-JxQ@mail.gmail.com>
On 12/23/25 00:09, Daeho Jeong wrote:
> On Mon, Dec 22, 2025 at 1:28 AM Chao Yu <chao@kernel.org> wrote:
>>
>> On 12/21/25 11:23, Daeho Jeong wrote:
>>> From: Daeho Jeong <daehojeong@google.com>
>>>
>>> The recent increase in the number of Segment Summary Area (SSA) entries
>>> from 512 to 2048 was an unintentional change in logic of 16kb block
>>> support. This commit corrects the issue.
>>>
>>> To better utilize the space available from the erroneous 2048-entry
>>> calculation, we are implementing a solution to share the currently
>>> unused SSA space with neighboring segments. This enhances overall
>>> SSA utilization without impacting the established 8MB segment size.
>>>
>>> Fixes: 50fd00b168d7 ("f2fs-tools: Support different block sizes")
>>> Signed-off-by: Daeho Jeong <daehojeong@google.com>
>>> ---
>>> v5: support both old and new format with packed_ssa feature option
>>> v4: move enabling the feature position.
>>> v3: add a feature to prevent from mounting deprecated format
>>> v2: detect legacy layout and prevent mount.
>>> fix ssa block calculation bug in resize tool.
>>> ---
>>> fsck/f2fs.h | 27 ++++++++++-
>>> fsck/fsck.c | 16 +++----
>>> fsck/inject.c | 4 +-
>>> fsck/mount.c | 51 ++++++++++-----------
>>> fsck/resize.c | 99 ++++++++++++++++++++++++++---------------
>>> include/f2fs_fs.h | 17 ++++---
>>> lib/libf2fs_io.c | 12 +++++
>>> mkfs/f2fs_format.c | 10 ++++-
>>> mkfs/f2fs_format_main.c | 6 +++
>>> 9 files changed, 158 insertions(+), 84 deletions(-)
>>>
>>> diff --git a/fsck/f2fs.h b/fsck/f2fs.h
>>> index 60e3a2e..5e7eb63 100644
>>> --- a/fsck/f2fs.h
>>> +++ b/fsck/f2fs.h
>>> @@ -447,12 +447,37 @@ static inline block_t __end_block_addr(struct f2fs_sb_info *sbi)
>>> (SM_I(sbi) ? SM_I(sbi)->seg0_blkaddr : \
>>> le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment0_blkaddr))
>>>
>>> +#define SUMS_PER_BLOCK (F2FS_BLKSIZE / F2FS_SUM_BLKSIZE)
>>> #define GET_SUM_BLKADDR(sbi, segno) \
>>> - ((sbi->sm_info->ssa_blkaddr) + segno)
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + ((SM_I(sbi)->ssa_blkaddr) + (segno) / SUMS_PER_BLOCK) : \
>>> + ((SM_I(sbi)->ssa_blkaddr) + (segno)))
>>> +#define GET_SUM_BLKOFF(segno) \
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + ((segno) % SUMS_PER_BLOCK) : 0)
>>>
>>> #define GET_SEGOFF_FROM_SEG0(sbi, blk_addr) \
>>> ((blk_addr) - SM_I(sbi)->seg0_blkaddr)
>>>
>>> +static inline int write_sum_block(struct f2fs_sb_info *sbi,
>>> + void *buf, unsigned int segno, enum rw_hint whint)
>>
>> What do you think of changing parameters as below?
>>
>> static inline int write_sum_block(struct f2fs_sb_info *sbi,
>> void *buf, block_t block, unsigned blkoff, enum rw_hint whint)
>>
>> So we can use this function to clean up codes in other places.
>
> If we pick this style, it will look more complicated, since we need to
> use the GET_SUM_BLKADDR
> and GET_SUM_BLKOFF everywhere outside of write/read_sum_block().
I think it's fine to spread GET_SUM_BLKADDR/GET_SUM_BLKOFF, but anyway, it's
fine to leave it as it is since it's minor cleanup.
>
>>
>>> +{
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + return dev_write_4k_block(buf, GET_SUM_BLKADDR(sbi, segno),
>>> + GET_SUM_BLKOFF(segno), whint);
>>> + return dev_write_block(buf, GET_SUM_BLKADDR(sbi, segno), whint);
>>> +}
>>> +
>>> +static inline int read_sum_block(struct f2fs_sb_info *sbi,
>>> + void *buf, unsigned int segno)
>>
>> Ditto,
>>
>>> +{
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + return dev_read_4k_block(buf, GET_SUM_BLKADDR(sbi, segno),
>>> + GET_SUM_BLKOFF(segno));
>>> + return dev_read_block(buf, GET_SUM_BLKADDR(sbi, segno));
>>> +}
>>> +
>>> +
>>> #define GET_SEGNO_FROM_SEG0(sbi, blk_addr) \
>>> (GET_SEGOFF_FROM_SEG0(sbi, blk_addr) >> sbi->log_blocks_per_seg)
>>>
>>> diff --git a/fsck/fsck.c b/fsck/fsck.c
>>> index 0b53c67..db44f9d 100644
>>> --- a/fsck/fsck.c
>>> +++ b/fsck/fsck.c
>>> @@ -228,11 +228,9 @@ static int is_valid_ssa_node_blk(struct f2fs_sb_info *sbi, u32 nid,
>>> }
>>> }
>>> if (need_fix && f2fs_dev_is_writable()) {
>>> - u64 ssa_blk;
>>> int ret2;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, segno);
>>> - ret2 = dev_write_block(sum_blk, ssa_blk, WRITE_LIFE_NONE);
>>> + ret2 = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret2 >= 0);
>>> }
>>> out:
>>> @@ -367,11 +365,9 @@ static int is_valid_ssa_data_blk(struct f2fs_sb_info *sbi, u32 blk_addr,
>>> }
>>> }
>>> if (need_fix && f2fs_dev_is_writable()) {
>>> - u64 ssa_blk;
>>> int ret2;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, segno);
>>> - ret2 = dev_write_block(sum_blk, ssa_blk, WRITE_LIFE_NONE);
>>> + ret2 = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret2 >= 0);
>>> }
>>> out:
>>> @@ -3879,14 +3875,12 @@ int fsck_verify(struct f2fs_sb_info *sbi)
>>> rewrite_sit_area_bitmap(sbi);
>>> if (c.zoned_model == F2FS_ZONED_HM) {
>>> struct curseg_info *curseg;
>>> - u64 ssa_blk;
>>>
>>> for (i = 0; i < NO_CHECK_TYPE; i++) {
>>> curseg = CURSEG_I(sbi, i);
>>> - ssa_blk = GET_SUM_BLKADDR(sbi,
>>> - curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk,
>>> - ssa_blk,
>>> + ret = write_sum_block(sbi,
>>> + curseg->sum_blk,
>>> + curseg->segno,
>>> WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> }
>>> diff --git a/fsck/inject.c b/fsck/inject.c
>>> index 0e46b1b..b00e356 100644
>>> --- a/fsck/inject.c
>>> +++ b/fsck/inject.c
>>> @@ -935,7 +935,6 @@ static int inject_ssa(struct f2fs_sb_info *sbi, struct inject_option *opt)
>>> struct summary_footer *footer;
>>> struct f2fs_summary *sum;
>>> u32 segno, offset;
>>> - block_t ssa_blkaddr;
>>> int type;
>>> int ret;
>>>
>>> @@ -1000,8 +999,7 @@ static int inject_ssa(struct f2fs_sb_info *sbi, struct inject_option *opt)
>>>
>>> print_sum_footer_info(footer);
>>>
>>> - ssa_blkaddr = GET_SUM_BLKADDR(sbi, segno);
>>> - ret = dev_write_block(sum_blk, ssa_blkaddr, WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>>
>>> out:
>>> diff --git a/fsck/mount.c b/fsck/mount.c
>>> index f03fa2d..43b1246 100644
>>> --- a/fsck/mount.c
>>> +++ b/fsck/mount.c
>>> @@ -2150,6 +2150,7 @@ static void read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>>> struct curseg_info *curseg;
>>> unsigned int segno = 0;
>>> block_t blk_addr = 0;
>>> + __u32 blk_offset = 0;
>>> int ret;
>>>
>>> if (IS_DATASEG(type)) {
>>> @@ -2160,24 +2161,29 @@ static void read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>>> blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
>>> } else {
>>> segno = get_cp(cur_node_segno[type - CURSEG_HOT_NODE]);
>>> - if (is_set_ckpt_flags(cp, CP_UMOUNT_FLAG))
>>> + if (is_set_ckpt_flags(cp, CP_UMOUNT_FLAG)) {
>>> blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
>>> type - CURSEG_HOT_NODE);
>>> - else
>>> + } else {
>>> blk_addr = GET_SUM_BLKADDR(sbi, segno);
>>> + blk_offset = GET_SUM_BLKOFF(segno);
>>> + }
>>> }
>>>
>>> - sum_blk = malloc(F2FS_BLKSIZE);
>>> + sum_blk = malloc(F2FS_SUM_BLKSIZE);
>>> ASSERT(sum_blk);
>>>
>>> - ret = dev_read_block(sum_blk, blk_addr);
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_read_4k_block(sum_blk, blk_addr, blk_offset);
>>> + else
>>> + ret = dev_read_block(sum_blk, blk_addr);
>>> ASSERT(ret >= 0);
>>>
>>> if (IS_NODESEG(type) && !is_set_ckpt_flags(cp, CP_UMOUNT_FLAG))
>>> restore_node_summary(sbi, segno, sum_blk);
>>>
>>> curseg = CURSEG_I(sbi, type);
>>> - memcpy(curseg->sum_blk, sum_blk, F2FS_BLKSIZE);
>>> + memcpy(curseg->sum_blk, sum_blk, F2FS_SUM_BLKSIZE);
>>> reset_curseg(sbi, type);
>>> free(sum_blk);
>>> }
>>> @@ -2205,8 +2211,7 @@ void update_sum_entry(struct f2fs_sb_info *sbi, block_t blk_addr,
>>> SUM_TYPE_DATA;
>>>
>>> /* write SSA all the time */
>>> - ret = dev_write_block(sum_blk, GET_SUM_BLKADDR(sbi, segno),
>>> - WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>>
>>> if (type == SEG_TYPE_NODE || type == SEG_TYPE_DATA ||
>>> @@ -2244,7 +2249,7 @@ static int build_curseg(struct f2fs_sb_info *sbi)
>>> SM_I(sbi)->curseg_array = array;
>>>
>>> for (i = 0; i < NR_CURSEG_TYPE; i++) {
>>> - array[i].sum_blk = calloc(F2FS_BLKSIZE, 1);
>>> + array[i].sum_blk = calloc(F2FS_SUM_BLKSIZE, 1);
>>> if (!array[i].sum_blk) {
>>> MSG(1, "\tError: Calloc failed for build_curseg!!\n");
>>> goto seg_cleanup;
>>> @@ -2405,11 +2410,9 @@ struct f2fs_summary_block *get_sum_block(struct f2fs_sb_info *sbi,
>>> struct f2fs_summary_block *sum_blk;
>>> struct curseg_info *curseg;
>>> int type, ret;
>>> - u64 ssa_blk;
>>>
>>> *ret_type= SEG_TYPE_MAX;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, segno);
>>> for (type = 0; type < NR_CURSEG_NODE_TYPE; type++) {
>>> curseg = CURSEG_I(sbi, CURSEG_HOT_NODE + type);
>>> if (segno == curseg->segno) {
>>> @@ -2440,10 +2443,10 @@ struct f2fs_summary_block *get_sum_block(struct f2fs_sb_info *sbi,
>>> }
>>> }
>>>
>>> - sum_blk = calloc(F2FS_BLKSIZE, 1);
>>> + sum_blk = calloc(F2FS_SUM_BLKSIZE, 1);
>>> ASSERT(sum_blk);
>>>
>>> - ret = dev_read_block(sum_blk, ssa_blk);
>>> + ret = read_sum_block(sbi, sum_blk, segno);
>>> ASSERT(ret >= 0);
>>>
>>> if (IS_SUM_NODE_SEG(sum_blk))
>>> @@ -3060,7 +3063,6 @@ int find_next_free_block(struct f2fs_sb_info *sbi, u64 *to, int left,
>>> struct curseg_info *curseg = CURSEG_I(sbi, want_type);
>>> unsigned int segs_per_zone = sbi->segs_per_sec * sbi->secs_per_zone;
>>> char buf[F2FS_BLKSIZE];
>>
>> char buf[F2FS_SUM_BLKSIZE];
>
> Got it.
>
>>
>>> - u64 ssa_blk;
>>> int ret;
>>>
>>> *to = NEXT_FREE_BLKADDR(sbi, curseg);
>>> @@ -3078,17 +3080,15 @@ int find_next_free_block(struct f2fs_sb_info *sbi, u64 *to, int left,
>>> segno = GET_SEGNO(sbi, new_blkaddr);
>>> }
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk, ssa_blk,
>>> - WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, curseg->sum_blk,
>>> + curseg->segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>>
>>> curseg->segno = segno;
>>> curseg->next_blkoff = 0;
>>> curseg->alloc_type = LFS;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_read_block(&buf, ssa_blk);
>>> + ret = read_sum_block(sbi, &buf, curseg->segno);
>>> ASSERT(ret >= 0);
>>>
>>> memcpy(curseg->sum_blk, &buf, SUM_ENTRIES_SIZE);
>>> @@ -3166,7 +3166,7 @@ void move_one_curseg_info(struct f2fs_sb_info *sbi, u64 from, int left,
>>> struct curseg_info *curseg = CURSEG_I(sbi, i);
>>> char buf[F2FS_BLKSIZE];
>>
>> char buf[F2FS_SUM_BLKSIZE];
>
> Got it.
>
>>
>>> u32 old_segno;
>>> - u64 ssa_blk, to;
>>> + u64 to;
>>> int ret;
>>>
>>> if ((get_sb(feature) & F2FS_FEATURE_RO)) {
>>> @@ -3184,8 +3184,8 @@ void move_one_curseg_info(struct f2fs_sb_info *sbi, u64 from, int left,
>>> }
>>>
>>> /* update original SSA too */
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk, ssa_blk, WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, curseg->sum_blk, curseg->segno,
>>> + WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> bypass_ssa:
>>> to = from;
>>> @@ -3199,8 +3199,7 @@ bypass_ssa:
>>> curseg->alloc_type = c.zoned_model == F2FS_ZONED_HM ? LFS : SSR;
>>>
>>> /* update new segno */
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_read_block(buf, ssa_blk);
>>> + ret = read_sum_block(sbi, buf, curseg->segno);
>>> ASSERT(ret >= 0);
>>>
>>> memcpy(curseg->sum_blk, buf, SUM_ENTRIES_SIZE);
>>> @@ -3464,7 +3463,6 @@ void write_checkpoint(struct f2fs_sb_info *sbi)
>>> /* update summary blocks having nullified journal entries */
>>> for (i = 0; i < NO_CHECK_TYPE; i++) {
>>> struct curseg_info *curseg = CURSEG_I(sbi, i);
>>> - u64 ssa_blk;
>>>
>>> if (!(flags & CP_UMOUNT_FLAG) && IS_NODESEG(i))
>>> continue;
>>> @@ -3475,9 +3473,8 @@ void write_checkpoint(struct f2fs_sb_info *sbi)
>>>
>>> if (!(get_sb(feature) & F2FS_FEATURE_RO)) {
>>> /* update original SSA too */
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk, ssa_blk,
>>> - WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, curseg->sum_blk,
>>> + curseg->segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> }
>>> }
>>> diff --git a/fsck/resize.c b/fsck/resize.c
>>> index bef05d6..e650283 100644
>>> --- a/fsck/resize.c
>>> +++ b/fsck/resize.c
>>> @@ -115,7 +115,11 @@ static int get_new_sb(struct f2fs_super_block *sb)
>>> get_sb(segment_count_sit) +
>>> get_sb(segment_count_nat))) * blks_per_seg;
>>>
>>> - blocks_for_ssa = total_valid_blks_available / blks_per_seg + 1;
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + blocks_for_ssa = round_up(total_valid_blks_available / blks_per_seg,
>>> + SUMS_PER_BLOCK);
>>> + else
>>> + blocks_for_ssa = total_valid_blks_available / blks_per_seg + 1;
>>>
>>> set_sb(segment_count_ssa, SEG_ALIGN(blocks_for_ssa));
>>>
>>> @@ -209,23 +213,36 @@ static void migrate_main(struct f2fs_sb_info *sbi, unsigned int offset)
>>> START_BLOCK(sbi, 0) + offset);
>>> }
>>>
>>> -static void move_ssa(struct f2fs_sb_info *sbi, unsigned int segno,
>>> - block_t new_sum_blk_addr)
>>> +#define GET_SUM_NEW_BLKADDR(new_sb, segno) \
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + (get_newsb(ssa_blkaddr) + \
>>> + (segno >> (get_newsb(log_blocksize) - DEFAULT_BLKSIZE_BITS))) : \
>>> + (get_newsb(ssa_blkaddr) + segno))
>>> +#define GET_SUM_NEW_BLKOFF(new_sb, segno) \
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + (segno % (1 << (get_newsb(log_blocksize) - DEFAULT_BLKSIZE_BITS))) : 0)
>>> +
>>> +static void move_ssa(struct f2fs_sb_info *sbi, struct f2fs_super_block *new_sb,
>>> + unsigned int old_segno, unsigned int new_segno)
>>> {
>>> struct f2fs_summary_block *sum_blk;
>>> int type;
>>>
>>> - sum_blk = get_sum_block(sbi, segno, &type);
>>> + sum_blk = get_sum_block(sbi, old_segno, &type);
>>> if (type < SEG_TYPE_MAX) {
>>> int ret;
>>> -
>>> - ret = dev_write_block(sum_blk, new_sum_blk_addr,
>>> - WRITE_LIFE_NONE);
>>> + u64 new_blkaddr = GET_SUM_NEW_BLKADDR(new_sb, new_segno);
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_write_4k_block(sum_blk, new_blkaddr,
>>> + GET_SUM_NEW_BLKOFF(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + else
>>> + ret = dev_write_block(sum_blk, new_blkaddr,
>>> + WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> DBG(1, "Write summary block: (%d) segno=%x/%x --> (%d) %x\n",
>>> - type, segno, GET_SUM_BLKADDR(sbi, segno),
>>> - IS_SUM_NODE_SEG(sum_blk),
>>> - new_sum_blk_addr);
>>> + type, old_segno, GET_SUM_BLKADDR(sbi, old_segno),
>>> + IS_SUM_NODE_SEG(sum_blk), (unsigned int)new_blkaddr);
>>> }
>>> if (type == SEG_TYPE_NODE || type == SEG_TYPE_DATA ||
>>> type == SEG_TYPE_MAX) {
>>> @@ -240,36 +257,48 @@ static void migrate_ssa(struct f2fs_sb_info *sbi,
>>> struct f2fs_super_block *sb = F2FS_RAW_SUPER(sbi);
>>> block_t old_sum_blkaddr = get_sb(ssa_blkaddr);
>>> block_t new_sum_blkaddr = get_newsb(ssa_blkaddr);
>>> - block_t end_sum_blkaddr = get_newsb(main_blkaddr);
>>> - block_t expand_sum_blkaddr = new_sum_blkaddr +
>>> - MAIN_SEGS(sbi) - offset;
>>> - block_t blkaddr;
>>> - int ret;
>>> - void *zero_block = calloc(F2FS_BLKSIZE, 1);
>>> + unsigned int expand_segno = MAIN_SEGS(sbi) - offset;
>>> + unsigned int new_seg_total = get_newsb(segment_count);
>>> + int new_segno;
>>> + int ret = 0;
>>> + void *zero_block = calloc(F2FS_SUM_BLKSIZE, 1);
>>> ASSERT(zero_block);
>>>
>>> - if (offset && new_sum_blkaddr < old_sum_blkaddr + offset) {
>>> - blkaddr = new_sum_blkaddr;
>>> - while (blkaddr < end_sum_blkaddr) {
>>> - if (blkaddr < expand_sum_blkaddr) {
>>> - move_ssa(sbi, offset++, blkaddr++);
>>> - } else {
>>> - ret = dev_write_block(zero_block, blkaddr++,
>>> - WRITE_LIFE_NONE);
>>> - ASSERT(ret >=0);
>>> - }
>>> + if (offset && new_sum_blkaddr <= (old_sum_blkaddr +
>>> + offset / SUMS_PER_BLOCK)) {
>>> + new_segno = 0;
>>> + while (new_segno < new_seg_total) {
>>> + if (new_segno < expand_segno)
>>> + move_ssa(sbi, new_sb, offset++, new_segno);
>>> + else if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_write_4k_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + GET_SUM_NEW_BLKOFF(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + else
>>> + ret = dev_write_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + ASSERT(ret >= 0);
>>> + new_segno++;
>>> }
>>> } else {
>>> - blkaddr = end_sum_blkaddr - 1;
>>> + new_segno = new_seg_total - 1;
>>> offset = MAIN_SEGS(sbi) - 1;
>>> - while (blkaddr >= new_sum_blkaddr) {
>>> - if (blkaddr >= expand_sum_blkaddr) {
>>> - ret = dev_write_block(zero_block, blkaddr--,
>>> - WRITE_LIFE_NONE);
>>> - ASSERT(ret >=0);
>>> - } else {
>>> - move_ssa(sbi, offset--, blkaddr--);
>>> - }
>>> + while (new_segno >= 0) {
>>> + if (new_segno < expand_segno)
>>> + move_ssa(sbi, new_sb, offset--, new_segno);
>>> + else if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_write_4k_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + GET_SUM_NEW_BLKOFF(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + else
>>> + ret = dev_write_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + ASSERT(ret >= 0);
>>> + new_segno--;
>>> }
>>> }
>>>
>>> diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
>>> index b85ded2..83e1484 100644
>>> --- a/include/f2fs_fs.h
>>> +++ b/include/f2fs_fs.h
>>> @@ -655,6 +655,7 @@ enum {
>>> #define F2FS_MIN_BLKSIZE 4096
>>> #define F2FS_MAX_BLKSIZE 16384
>>> #define F2FS_BLKSIZE c.blksize /* support configurable block size */
>>> +#define F2FS_SUM_BLKSIZE ((c.feature & F2FS_FEATURE_PACKED_SSA) ? 4096 : F2FS_BLKSIZE)
>>
>> How about using F2FS_MIN_BLKSIZE instead of all magic number 4096?
>
> Got it.
>
>>
>>> #define F2FS_MAX_EXTENSION 64 /* # of extension entries */
>>> #define F2FS_EXTENSION_LEN 8 /* max size of extension */
>>> #define F2FS_BLK_ALIGN(x) (((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
>>> @@ -715,6 +716,7 @@ enum {
>>> #define F2FS_FEATURE_COMPRESSION 0x2000
>>> #define F2FS_FEATURE_RO 0x4000
>>> #define F2FS_FEATURE_DEVICE_ALIAS 0x8000
>>> +#define F2FS_FEATURE_PACKED_SSA 0x10000
>>>
>>> #define MAX_NR_FEATURE 32
>>>
>>> @@ -1219,7 +1221,7 @@ struct f2fs_sit_block {
>>> * from node's page's beginning to get a data block address.
>>> * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
>>> */
>>> -#define ENTRIES_IN_SUM (F2FS_BLKSIZE / 8)
>>> +#define ENTRIES_IN_SUM (F2FS_SUM_BLKSIZE / 8)
>>> #define SUMMARY_SIZE (7) /* sizeof(struct summary) */
>>> #define SUM_FOOTER_SIZE (5) /* sizeof(struct summary_footer) */
>>> #define SUM_ENTRIES_SIZE (SUMMARY_SIZE * ENTRIES_IN_SUM)
>>> @@ -1249,7 +1251,7 @@ struct summary_footer {
>>>
>>> static_assert(sizeof(struct summary_footer) == 5, "");
>>>
>>> -#define SUM_JOURNAL_SIZE (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
>>> +#define SUM_JOURNAL_SIZE (F2FS_SUM_BLKSIZE - SUM_FOOTER_SIZE -\
>>> SUM_ENTRIES_SIZE)
>>> #define NAT_JOURNAL_ENTRIES ((SUM_JOURNAL_SIZE - 2) /\
>>> sizeof(struct nat_journal_entry))
>>> @@ -1348,7 +1350,7 @@ struct f2fs_summary_block {
>>> };
>>> #define F2FS_SUMMARY_BLOCK_JOURNAL(blk) ((struct f2fs_journal *)(&(blk)->entries[ENTRIES_IN_SUM]))
>>> #define F2FS_SUMMARY_BLOCK_FOOTER(blk) ((struct summary_footer *)&((char *)\
>>> - (&(blk)->entries[0]))[F2FS_BLKSIZE - SUM_FOOTER_SIZE])
>>> + (&(blk)->entries[0]))[F2FS_SUM_BLKSIZE - SUM_FOOTER_SIZE])
>>>
>>> /*
>>> * For directory operations
>>> @@ -1711,6 +1713,8 @@ extern int dev_fill_block(void *, __u64, enum rw_hint);
>>>
>>> extern int dev_read_block(void *, __u64);
>>> extern int dev_reada_block(__u64);
>>> +extern int dev_write_4k_block(void *, __u64, __u32, enum rw_hint);
>>> +extern int dev_read_4k_block(void *, __u64, __u32);
>>>
>>> extern int dev_read_version(void *, __u64, size_t);
>>> extern void get_kernel_version(__u8 *);
>>> @@ -2022,6 +2026,7 @@ struct feature feature_table[] = { \
>>> { "compression", F2FS_FEATURE_COMPRESSION, 1}, \
>>> { "ro", F2FS_FEATURE_RO, 1}, \
>>> { "device_alias", F2FS_FEATURE_DEVICE_ALIAS, 0}, \
>>> + { "packed_ssa", F2FS_FEATURE_PACKED_SSA, 1}, \
>>
>> ^
>> IIUC, this feature can not be tunned by fsck? since it will change the disk layout?
> > We need to turn on/off with the mkfs option. Can we set/clear in
> superblock with fsck?
Oh, I missed to check tune_sb_features(), fsck can only set encrypt/casefold feature
rather than all features w/ settable field == 1.
Thanks,
>
>>
>> Thanks,
>>
>>> { NULL, 0x0, 0}, \
>>> };
>>>
>>> @@ -2161,18 +2166,18 @@ static inline void check_block_struct_sizes(void)
>>> assert(sizeof(struct f2fs_summary) * ENTRIES_IN_SUM
>>> + offsetof(struct f2fs_journal, nat_j)
>>> + NAT_JOURNAL_ENTRIES * sizeof(struct nat_journal_entry)
>>> - + NAT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_BLKSIZE);
>>> + + NAT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_SUM_BLKSIZE);
>>>
>>> /* Check SIT Journal Block Size */
>>> assert(sizeof(struct f2fs_summary) * ENTRIES_IN_SUM
>>> + offsetof(struct f2fs_journal, sit_j)
>>> + SIT_JOURNAL_ENTRIES * sizeof(struct sit_journal_entry)
>>> - + SIT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_BLKSIZE);
>>> + + SIT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_SUM_BLKSIZE);
>>>
>>> /* Check Info Journal Block Size */
>>> assert(sizeof(struct f2fs_summary) * ENTRIES_IN_SUM + sizeof(__le64)
>>> + offsetof(struct f2fs_journal, info)
>>> - + EXTRA_INFO_RESERVED + sizeof(struct summary_footer) == F2FS_BLKSIZE);
>>> + + EXTRA_INFO_RESERVED + sizeof(struct summary_footer) == F2FS_SUM_BLKSIZE);
>>>
>>> /* Check Dentry Block Size */
>>> assert(sizeof(__u8) * (SIZE_OF_DENTRY_BITMAP + SIZE_OF_RESERVED)
>>> diff --git a/lib/libf2fs_io.c b/lib/libf2fs_io.c
>>> index c31f3b8..deafc4f 100644
>>> --- a/lib/libf2fs_io.c
>>> +++ b/lib/libf2fs_io.c
>>> @@ -734,6 +734,18 @@ int dev_reada_block(__u64 blk_addr)
>>> return dev_readahead(blk_addr << F2FS_BLKSIZE_BITS, F2FS_BLKSIZE);
>>> }
>>>
>>> +int dev_write_4k_block(void *buf, __u64 blk_addr, __u32 offset, enum rw_hint whint)
>>> +{
>>> + return dev_write(buf, (blk_addr << F2FS_BLKSIZE_BITS) + offset * 4096,
>>> + 4096, whint);
>>> +}
>>> +
>>> +int dev_read_4k_block(void *buf, __u64 blk_addr, __u32 offset)
>>> +{
>>> + return dev_read(buf, (blk_addr << F2FS_BLKSIZE_BITS) + offset * 4096,
>>> + 4096);
>>> +}
>>> +
>>> int f2fs_fsync_device(void)
>>> {
>>> #ifdef HAVE_FSYNC
>>> diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
>>> index d05e897..b3dccd0 100644
>>> --- a/mkfs/f2fs_format.c
>>> +++ b/mkfs/f2fs_format.c
>>> @@ -500,8 +500,16 @@ static int f2fs_prepare_super_block(void)
>>> if (c.feature & F2FS_FEATURE_RO) {
>>> blocks_for_ssa = 0;
>>> } else {
>>> + unsigned int ssa_per_block;
>>> +
>>> ASSERT((total_valid_blks_available % c.blks_per_seg) == 0);
>>> - blocks_for_ssa = total_valid_blks_available / c.blks_per_seg;
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA) {
>>> + ssa_per_block = c.blksize / F2FS_SUM_BLKSIZE;
>>> + blocks_for_ssa = round_up(total_valid_blks_available /
>>> + c.blks_per_seg, ssa_per_block);
>>> + } else {
>>> + blocks_for_ssa = total_valid_blks_available / c.blks_per_seg;
>>> + }
>>> }
>>>
>>> set_sb(segment_count_ssa, SEG_ALIGN(blocks_for_ssa));
>>> diff --git a/mkfs/f2fs_format_main.c b/mkfs/f2fs_format_main.c
>>> index 8f8e975..8d44a9b 100644
>>> --- a/mkfs/f2fs_format_main.c
>>> +++ b/mkfs/f2fs_format_main.c
>>> @@ -380,6 +380,12 @@ static void f2fs_parse_options(int argc, char *argv[])
>>> }
>>> }
>>>
>>> + if ((c.feature & F2FS_FEATURE_PACKED_SSA) &&
>>> + (c.blksize == F2FS_MIN_BLKSIZE)) {
>>> + c.feature &= ~F2FS_FEATURE_PACKED_SSA;
>>> + MSG(0, "\tInfo: packed_ssa feature is disabled for 4k block.\n");
>>> + }
>>> +
>>> if (optind >= argc) {
>>> MSG(0, "\tError: Device not specified\n");
>>> mkfs_usage();
>>
_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
WARNING: multiple messages have this Message-ID (diff)
From: Chao Yu <chao@kernel.org>
To: Daeho Jeong <daeho43@gmail.com>
Cc: chao@kernel.org, linux-kernel@vger.kernel.org,
linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
Daeho Jeong <daehojeong@google.com>
Subject: Re: [f2fs-dev] [PATCH v5] f2fs-tools: revert summary entry count from 2048 to 512 in 16kb block support
Date: Tue, 23 Dec 2025 10:33:59 +0800 [thread overview]
Message-ID: <04a4dcd6-e8cb-4378-bf79-e4e90af17e87@kernel.org> (raw)
In-Reply-To: <CACOAw_z+uTang-h44ROsKU5vxVZGUE7UJR2TF9zYdg5OXB-JxQ@mail.gmail.com>
On 12/23/25 00:09, Daeho Jeong wrote:
> On Mon, Dec 22, 2025 at 1:28 AM Chao Yu <chao@kernel.org> wrote:
>>
>> On 12/21/25 11:23, Daeho Jeong wrote:
>>> From: Daeho Jeong <daehojeong@google.com>
>>>
>>> The recent increase in the number of Segment Summary Area (SSA) entries
>>> from 512 to 2048 was an unintentional change in logic of 16kb block
>>> support. This commit corrects the issue.
>>>
>>> To better utilize the space available from the erroneous 2048-entry
>>> calculation, we are implementing a solution to share the currently
>>> unused SSA space with neighboring segments. This enhances overall
>>> SSA utilization without impacting the established 8MB segment size.
>>>
>>> Fixes: 50fd00b168d7 ("f2fs-tools: Support different block sizes")
>>> Signed-off-by: Daeho Jeong <daehojeong@google.com>
>>> ---
>>> v5: support both old and new format with packed_ssa feature option
>>> v4: move enabling the feature position.
>>> v3: add a feature to prevent from mounting deprecated format
>>> v2: detect legacy layout and prevent mount.
>>> fix ssa block calculation bug in resize tool.
>>> ---
>>> fsck/f2fs.h | 27 ++++++++++-
>>> fsck/fsck.c | 16 +++----
>>> fsck/inject.c | 4 +-
>>> fsck/mount.c | 51 ++++++++++-----------
>>> fsck/resize.c | 99 ++++++++++++++++++++++++++---------------
>>> include/f2fs_fs.h | 17 ++++---
>>> lib/libf2fs_io.c | 12 +++++
>>> mkfs/f2fs_format.c | 10 ++++-
>>> mkfs/f2fs_format_main.c | 6 +++
>>> 9 files changed, 158 insertions(+), 84 deletions(-)
>>>
>>> diff --git a/fsck/f2fs.h b/fsck/f2fs.h
>>> index 60e3a2e..5e7eb63 100644
>>> --- a/fsck/f2fs.h
>>> +++ b/fsck/f2fs.h
>>> @@ -447,12 +447,37 @@ static inline block_t __end_block_addr(struct f2fs_sb_info *sbi)
>>> (SM_I(sbi) ? SM_I(sbi)->seg0_blkaddr : \
>>> le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment0_blkaddr))
>>>
>>> +#define SUMS_PER_BLOCK (F2FS_BLKSIZE / F2FS_SUM_BLKSIZE)
>>> #define GET_SUM_BLKADDR(sbi, segno) \
>>> - ((sbi->sm_info->ssa_blkaddr) + segno)
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + ((SM_I(sbi)->ssa_blkaddr) + (segno) / SUMS_PER_BLOCK) : \
>>> + ((SM_I(sbi)->ssa_blkaddr) + (segno)))
>>> +#define GET_SUM_BLKOFF(segno) \
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + ((segno) % SUMS_PER_BLOCK) : 0)
>>>
>>> #define GET_SEGOFF_FROM_SEG0(sbi, blk_addr) \
>>> ((blk_addr) - SM_I(sbi)->seg0_blkaddr)
>>>
>>> +static inline int write_sum_block(struct f2fs_sb_info *sbi,
>>> + void *buf, unsigned int segno, enum rw_hint whint)
>>
>> What do you think of changing parameters as below?
>>
>> static inline int write_sum_block(struct f2fs_sb_info *sbi,
>> void *buf, block_t block, unsigned blkoff, enum rw_hint whint)
>>
>> So we can use this function to clean up codes in other places.
>
> If we pick this style, it will look more complicated, since we need to
> use the GET_SUM_BLKADDR
> and GET_SUM_BLKOFF everywhere outside of write/read_sum_block().
I think it's fine to spread GET_SUM_BLKADDR/GET_SUM_BLKOFF, but anyway, it's
fine to leave it as it is since it's minor cleanup.
>
>>
>>> +{
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + return dev_write_4k_block(buf, GET_SUM_BLKADDR(sbi, segno),
>>> + GET_SUM_BLKOFF(segno), whint);
>>> + return dev_write_block(buf, GET_SUM_BLKADDR(sbi, segno), whint);
>>> +}
>>> +
>>> +static inline int read_sum_block(struct f2fs_sb_info *sbi,
>>> + void *buf, unsigned int segno)
>>
>> Ditto,
>>
>>> +{
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + return dev_read_4k_block(buf, GET_SUM_BLKADDR(sbi, segno),
>>> + GET_SUM_BLKOFF(segno));
>>> + return dev_read_block(buf, GET_SUM_BLKADDR(sbi, segno));
>>> +}
>>> +
>>> +
>>> #define GET_SEGNO_FROM_SEG0(sbi, blk_addr) \
>>> (GET_SEGOFF_FROM_SEG0(sbi, blk_addr) >> sbi->log_blocks_per_seg)
>>>
>>> diff --git a/fsck/fsck.c b/fsck/fsck.c
>>> index 0b53c67..db44f9d 100644
>>> --- a/fsck/fsck.c
>>> +++ b/fsck/fsck.c
>>> @@ -228,11 +228,9 @@ static int is_valid_ssa_node_blk(struct f2fs_sb_info *sbi, u32 nid,
>>> }
>>> }
>>> if (need_fix && f2fs_dev_is_writable()) {
>>> - u64 ssa_blk;
>>> int ret2;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, segno);
>>> - ret2 = dev_write_block(sum_blk, ssa_blk, WRITE_LIFE_NONE);
>>> + ret2 = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret2 >= 0);
>>> }
>>> out:
>>> @@ -367,11 +365,9 @@ static int is_valid_ssa_data_blk(struct f2fs_sb_info *sbi, u32 blk_addr,
>>> }
>>> }
>>> if (need_fix && f2fs_dev_is_writable()) {
>>> - u64 ssa_blk;
>>> int ret2;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, segno);
>>> - ret2 = dev_write_block(sum_blk, ssa_blk, WRITE_LIFE_NONE);
>>> + ret2 = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret2 >= 0);
>>> }
>>> out:
>>> @@ -3879,14 +3875,12 @@ int fsck_verify(struct f2fs_sb_info *sbi)
>>> rewrite_sit_area_bitmap(sbi);
>>> if (c.zoned_model == F2FS_ZONED_HM) {
>>> struct curseg_info *curseg;
>>> - u64 ssa_blk;
>>>
>>> for (i = 0; i < NO_CHECK_TYPE; i++) {
>>> curseg = CURSEG_I(sbi, i);
>>> - ssa_blk = GET_SUM_BLKADDR(sbi,
>>> - curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk,
>>> - ssa_blk,
>>> + ret = write_sum_block(sbi,
>>> + curseg->sum_blk,
>>> + curseg->segno,
>>> WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> }
>>> diff --git a/fsck/inject.c b/fsck/inject.c
>>> index 0e46b1b..b00e356 100644
>>> --- a/fsck/inject.c
>>> +++ b/fsck/inject.c
>>> @@ -935,7 +935,6 @@ static int inject_ssa(struct f2fs_sb_info *sbi, struct inject_option *opt)
>>> struct summary_footer *footer;
>>> struct f2fs_summary *sum;
>>> u32 segno, offset;
>>> - block_t ssa_blkaddr;
>>> int type;
>>> int ret;
>>>
>>> @@ -1000,8 +999,7 @@ static int inject_ssa(struct f2fs_sb_info *sbi, struct inject_option *opt)
>>>
>>> print_sum_footer_info(footer);
>>>
>>> - ssa_blkaddr = GET_SUM_BLKADDR(sbi, segno);
>>> - ret = dev_write_block(sum_blk, ssa_blkaddr, WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>>
>>> out:
>>> diff --git a/fsck/mount.c b/fsck/mount.c
>>> index f03fa2d..43b1246 100644
>>> --- a/fsck/mount.c
>>> +++ b/fsck/mount.c
>>> @@ -2150,6 +2150,7 @@ static void read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>>> struct curseg_info *curseg;
>>> unsigned int segno = 0;
>>> block_t blk_addr = 0;
>>> + __u32 blk_offset = 0;
>>> int ret;
>>>
>>> if (IS_DATASEG(type)) {
>>> @@ -2160,24 +2161,29 @@ static void read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>>> blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
>>> } else {
>>> segno = get_cp(cur_node_segno[type - CURSEG_HOT_NODE]);
>>> - if (is_set_ckpt_flags(cp, CP_UMOUNT_FLAG))
>>> + if (is_set_ckpt_flags(cp, CP_UMOUNT_FLAG)) {
>>> blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
>>> type - CURSEG_HOT_NODE);
>>> - else
>>> + } else {
>>> blk_addr = GET_SUM_BLKADDR(sbi, segno);
>>> + blk_offset = GET_SUM_BLKOFF(segno);
>>> + }
>>> }
>>>
>>> - sum_blk = malloc(F2FS_BLKSIZE);
>>> + sum_blk = malloc(F2FS_SUM_BLKSIZE);
>>> ASSERT(sum_blk);
>>>
>>> - ret = dev_read_block(sum_blk, blk_addr);
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_read_4k_block(sum_blk, blk_addr, blk_offset);
>>> + else
>>> + ret = dev_read_block(sum_blk, blk_addr);
>>> ASSERT(ret >= 0);
>>>
>>> if (IS_NODESEG(type) && !is_set_ckpt_flags(cp, CP_UMOUNT_FLAG))
>>> restore_node_summary(sbi, segno, sum_blk);
>>>
>>> curseg = CURSEG_I(sbi, type);
>>> - memcpy(curseg->sum_blk, sum_blk, F2FS_BLKSIZE);
>>> + memcpy(curseg->sum_blk, sum_blk, F2FS_SUM_BLKSIZE);
>>> reset_curseg(sbi, type);
>>> free(sum_blk);
>>> }
>>> @@ -2205,8 +2211,7 @@ void update_sum_entry(struct f2fs_sb_info *sbi, block_t blk_addr,
>>> SUM_TYPE_DATA;
>>>
>>> /* write SSA all the time */
>>> - ret = dev_write_block(sum_blk, GET_SUM_BLKADDR(sbi, segno),
>>> - WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, sum_blk, segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>>
>>> if (type == SEG_TYPE_NODE || type == SEG_TYPE_DATA ||
>>> @@ -2244,7 +2249,7 @@ static int build_curseg(struct f2fs_sb_info *sbi)
>>> SM_I(sbi)->curseg_array = array;
>>>
>>> for (i = 0; i < NR_CURSEG_TYPE; i++) {
>>> - array[i].sum_blk = calloc(F2FS_BLKSIZE, 1);
>>> + array[i].sum_blk = calloc(F2FS_SUM_BLKSIZE, 1);
>>> if (!array[i].sum_blk) {
>>> MSG(1, "\tError: Calloc failed for build_curseg!!\n");
>>> goto seg_cleanup;
>>> @@ -2405,11 +2410,9 @@ struct f2fs_summary_block *get_sum_block(struct f2fs_sb_info *sbi,
>>> struct f2fs_summary_block *sum_blk;
>>> struct curseg_info *curseg;
>>> int type, ret;
>>> - u64 ssa_blk;
>>>
>>> *ret_type= SEG_TYPE_MAX;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, segno);
>>> for (type = 0; type < NR_CURSEG_NODE_TYPE; type++) {
>>> curseg = CURSEG_I(sbi, CURSEG_HOT_NODE + type);
>>> if (segno == curseg->segno) {
>>> @@ -2440,10 +2443,10 @@ struct f2fs_summary_block *get_sum_block(struct f2fs_sb_info *sbi,
>>> }
>>> }
>>>
>>> - sum_blk = calloc(F2FS_BLKSIZE, 1);
>>> + sum_blk = calloc(F2FS_SUM_BLKSIZE, 1);
>>> ASSERT(sum_blk);
>>>
>>> - ret = dev_read_block(sum_blk, ssa_blk);
>>> + ret = read_sum_block(sbi, sum_blk, segno);
>>> ASSERT(ret >= 0);
>>>
>>> if (IS_SUM_NODE_SEG(sum_blk))
>>> @@ -3060,7 +3063,6 @@ int find_next_free_block(struct f2fs_sb_info *sbi, u64 *to, int left,
>>> struct curseg_info *curseg = CURSEG_I(sbi, want_type);
>>> unsigned int segs_per_zone = sbi->segs_per_sec * sbi->secs_per_zone;
>>> char buf[F2FS_BLKSIZE];
>>
>> char buf[F2FS_SUM_BLKSIZE];
>
> Got it.
>
>>
>>> - u64 ssa_blk;
>>> int ret;
>>>
>>> *to = NEXT_FREE_BLKADDR(sbi, curseg);
>>> @@ -3078,17 +3080,15 @@ int find_next_free_block(struct f2fs_sb_info *sbi, u64 *to, int left,
>>> segno = GET_SEGNO(sbi, new_blkaddr);
>>> }
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk, ssa_blk,
>>> - WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, curseg->sum_blk,
>>> + curseg->segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>>
>>> curseg->segno = segno;
>>> curseg->next_blkoff = 0;
>>> curseg->alloc_type = LFS;
>>>
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_read_block(&buf, ssa_blk);
>>> + ret = read_sum_block(sbi, &buf, curseg->segno);
>>> ASSERT(ret >= 0);
>>>
>>> memcpy(curseg->sum_blk, &buf, SUM_ENTRIES_SIZE);
>>> @@ -3166,7 +3166,7 @@ void move_one_curseg_info(struct f2fs_sb_info *sbi, u64 from, int left,
>>> struct curseg_info *curseg = CURSEG_I(sbi, i);
>>> char buf[F2FS_BLKSIZE];
>>
>> char buf[F2FS_SUM_BLKSIZE];
>
> Got it.
>
>>
>>> u32 old_segno;
>>> - u64 ssa_blk, to;
>>> + u64 to;
>>> int ret;
>>>
>>> if ((get_sb(feature) & F2FS_FEATURE_RO)) {
>>> @@ -3184,8 +3184,8 @@ void move_one_curseg_info(struct f2fs_sb_info *sbi, u64 from, int left,
>>> }
>>>
>>> /* update original SSA too */
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk, ssa_blk, WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, curseg->sum_blk, curseg->segno,
>>> + WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> bypass_ssa:
>>> to = from;
>>> @@ -3199,8 +3199,7 @@ bypass_ssa:
>>> curseg->alloc_type = c.zoned_model == F2FS_ZONED_HM ? LFS : SSR;
>>>
>>> /* update new segno */
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_read_block(buf, ssa_blk);
>>> + ret = read_sum_block(sbi, buf, curseg->segno);
>>> ASSERT(ret >= 0);
>>>
>>> memcpy(curseg->sum_blk, buf, SUM_ENTRIES_SIZE);
>>> @@ -3464,7 +3463,6 @@ void write_checkpoint(struct f2fs_sb_info *sbi)
>>> /* update summary blocks having nullified journal entries */
>>> for (i = 0; i < NO_CHECK_TYPE; i++) {
>>> struct curseg_info *curseg = CURSEG_I(sbi, i);
>>> - u64 ssa_blk;
>>>
>>> if (!(flags & CP_UMOUNT_FLAG) && IS_NODESEG(i))
>>> continue;
>>> @@ -3475,9 +3473,8 @@ void write_checkpoint(struct f2fs_sb_info *sbi)
>>>
>>> if (!(get_sb(feature) & F2FS_FEATURE_RO)) {
>>> /* update original SSA too */
>>> - ssa_blk = GET_SUM_BLKADDR(sbi, curseg->segno);
>>> - ret = dev_write_block(curseg->sum_blk, ssa_blk,
>>> - WRITE_LIFE_NONE);
>>> + ret = write_sum_block(sbi, curseg->sum_blk,
>>> + curseg->segno, WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> }
>>> }
>>> diff --git a/fsck/resize.c b/fsck/resize.c
>>> index bef05d6..e650283 100644
>>> --- a/fsck/resize.c
>>> +++ b/fsck/resize.c
>>> @@ -115,7 +115,11 @@ static int get_new_sb(struct f2fs_super_block *sb)
>>> get_sb(segment_count_sit) +
>>> get_sb(segment_count_nat))) * blks_per_seg;
>>>
>>> - blocks_for_ssa = total_valid_blks_available / blks_per_seg + 1;
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + blocks_for_ssa = round_up(total_valid_blks_available / blks_per_seg,
>>> + SUMS_PER_BLOCK);
>>> + else
>>> + blocks_for_ssa = total_valid_blks_available / blks_per_seg + 1;
>>>
>>> set_sb(segment_count_ssa, SEG_ALIGN(blocks_for_ssa));
>>>
>>> @@ -209,23 +213,36 @@ static void migrate_main(struct f2fs_sb_info *sbi, unsigned int offset)
>>> START_BLOCK(sbi, 0) + offset);
>>> }
>>>
>>> -static void move_ssa(struct f2fs_sb_info *sbi, unsigned int segno,
>>> - block_t new_sum_blk_addr)
>>> +#define GET_SUM_NEW_BLKADDR(new_sb, segno) \
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + (get_newsb(ssa_blkaddr) + \
>>> + (segno >> (get_newsb(log_blocksize) - DEFAULT_BLKSIZE_BITS))) : \
>>> + (get_newsb(ssa_blkaddr) + segno))
>>> +#define GET_SUM_NEW_BLKOFF(new_sb, segno) \
>>> + (c.feature & F2FS_FEATURE_PACKED_SSA ? \
>>> + (segno % (1 << (get_newsb(log_blocksize) - DEFAULT_BLKSIZE_BITS))) : 0)
>>> +
>>> +static void move_ssa(struct f2fs_sb_info *sbi, struct f2fs_super_block *new_sb,
>>> + unsigned int old_segno, unsigned int new_segno)
>>> {
>>> struct f2fs_summary_block *sum_blk;
>>> int type;
>>>
>>> - sum_blk = get_sum_block(sbi, segno, &type);
>>> + sum_blk = get_sum_block(sbi, old_segno, &type);
>>> if (type < SEG_TYPE_MAX) {
>>> int ret;
>>> -
>>> - ret = dev_write_block(sum_blk, new_sum_blk_addr,
>>> - WRITE_LIFE_NONE);
>>> + u64 new_blkaddr = GET_SUM_NEW_BLKADDR(new_sb, new_segno);
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_write_4k_block(sum_blk, new_blkaddr,
>>> + GET_SUM_NEW_BLKOFF(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + else
>>> + ret = dev_write_block(sum_blk, new_blkaddr,
>>> + WRITE_LIFE_NONE);
>>> ASSERT(ret >= 0);
>>> DBG(1, "Write summary block: (%d) segno=%x/%x --> (%d) %x\n",
>>> - type, segno, GET_SUM_BLKADDR(sbi, segno),
>>> - IS_SUM_NODE_SEG(sum_blk),
>>> - new_sum_blk_addr);
>>> + type, old_segno, GET_SUM_BLKADDR(sbi, old_segno),
>>> + IS_SUM_NODE_SEG(sum_blk), (unsigned int)new_blkaddr);
>>> }
>>> if (type == SEG_TYPE_NODE || type == SEG_TYPE_DATA ||
>>> type == SEG_TYPE_MAX) {
>>> @@ -240,36 +257,48 @@ static void migrate_ssa(struct f2fs_sb_info *sbi,
>>> struct f2fs_super_block *sb = F2FS_RAW_SUPER(sbi);
>>> block_t old_sum_blkaddr = get_sb(ssa_blkaddr);
>>> block_t new_sum_blkaddr = get_newsb(ssa_blkaddr);
>>> - block_t end_sum_blkaddr = get_newsb(main_blkaddr);
>>> - block_t expand_sum_blkaddr = new_sum_blkaddr +
>>> - MAIN_SEGS(sbi) - offset;
>>> - block_t blkaddr;
>>> - int ret;
>>> - void *zero_block = calloc(F2FS_BLKSIZE, 1);
>>> + unsigned int expand_segno = MAIN_SEGS(sbi) - offset;
>>> + unsigned int new_seg_total = get_newsb(segment_count);
>>> + int new_segno;
>>> + int ret = 0;
>>> + void *zero_block = calloc(F2FS_SUM_BLKSIZE, 1);
>>> ASSERT(zero_block);
>>>
>>> - if (offset && new_sum_blkaddr < old_sum_blkaddr + offset) {
>>> - blkaddr = new_sum_blkaddr;
>>> - while (blkaddr < end_sum_blkaddr) {
>>> - if (blkaddr < expand_sum_blkaddr) {
>>> - move_ssa(sbi, offset++, blkaddr++);
>>> - } else {
>>> - ret = dev_write_block(zero_block, blkaddr++,
>>> - WRITE_LIFE_NONE);
>>> - ASSERT(ret >=0);
>>> - }
>>> + if (offset && new_sum_blkaddr <= (old_sum_blkaddr +
>>> + offset / SUMS_PER_BLOCK)) {
>>> + new_segno = 0;
>>> + while (new_segno < new_seg_total) {
>>> + if (new_segno < expand_segno)
>>> + move_ssa(sbi, new_sb, offset++, new_segno);
>>> + else if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_write_4k_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + GET_SUM_NEW_BLKOFF(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + else
>>> + ret = dev_write_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + ASSERT(ret >= 0);
>>> + new_segno++;
>>> }
>>> } else {
>>> - blkaddr = end_sum_blkaddr - 1;
>>> + new_segno = new_seg_total - 1;
>>> offset = MAIN_SEGS(sbi) - 1;
>>> - while (blkaddr >= new_sum_blkaddr) {
>>> - if (blkaddr >= expand_sum_blkaddr) {
>>> - ret = dev_write_block(zero_block, blkaddr--,
>>> - WRITE_LIFE_NONE);
>>> - ASSERT(ret >=0);
>>> - } else {
>>> - move_ssa(sbi, offset--, blkaddr--);
>>> - }
>>> + while (new_segno >= 0) {
>>> + if (new_segno < expand_segno)
>>> + move_ssa(sbi, new_sb, offset--, new_segno);
>>> + else if (c.feature & F2FS_FEATURE_PACKED_SSA)
>>> + ret = dev_write_4k_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + GET_SUM_NEW_BLKOFF(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + else
>>> + ret = dev_write_block(zero_block,
>>> + GET_SUM_NEW_BLKADDR(new_sb, new_segno),
>>> + WRITE_LIFE_NONE);
>>> + ASSERT(ret >= 0);
>>> + new_segno--;
>>> }
>>> }
>>>
>>> diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
>>> index b85ded2..83e1484 100644
>>> --- a/include/f2fs_fs.h
>>> +++ b/include/f2fs_fs.h
>>> @@ -655,6 +655,7 @@ enum {
>>> #define F2FS_MIN_BLKSIZE 4096
>>> #define F2FS_MAX_BLKSIZE 16384
>>> #define F2FS_BLKSIZE c.blksize /* support configurable block size */
>>> +#define F2FS_SUM_BLKSIZE ((c.feature & F2FS_FEATURE_PACKED_SSA) ? 4096 : F2FS_BLKSIZE)
>>
>> How about using F2FS_MIN_BLKSIZE instead of all magic number 4096?
>
> Got it.
>
>>
>>> #define F2FS_MAX_EXTENSION 64 /* # of extension entries */
>>> #define F2FS_EXTENSION_LEN 8 /* max size of extension */
>>> #define F2FS_BLK_ALIGN(x) (((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
>>> @@ -715,6 +716,7 @@ enum {
>>> #define F2FS_FEATURE_COMPRESSION 0x2000
>>> #define F2FS_FEATURE_RO 0x4000
>>> #define F2FS_FEATURE_DEVICE_ALIAS 0x8000
>>> +#define F2FS_FEATURE_PACKED_SSA 0x10000
>>>
>>> #define MAX_NR_FEATURE 32
>>>
>>> @@ -1219,7 +1221,7 @@ struct f2fs_sit_block {
>>> * from node's page's beginning to get a data block address.
>>> * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
>>> */
>>> -#define ENTRIES_IN_SUM (F2FS_BLKSIZE / 8)
>>> +#define ENTRIES_IN_SUM (F2FS_SUM_BLKSIZE / 8)
>>> #define SUMMARY_SIZE (7) /* sizeof(struct summary) */
>>> #define SUM_FOOTER_SIZE (5) /* sizeof(struct summary_footer) */
>>> #define SUM_ENTRIES_SIZE (SUMMARY_SIZE * ENTRIES_IN_SUM)
>>> @@ -1249,7 +1251,7 @@ struct summary_footer {
>>>
>>> static_assert(sizeof(struct summary_footer) == 5, "");
>>>
>>> -#define SUM_JOURNAL_SIZE (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
>>> +#define SUM_JOURNAL_SIZE (F2FS_SUM_BLKSIZE - SUM_FOOTER_SIZE -\
>>> SUM_ENTRIES_SIZE)
>>> #define NAT_JOURNAL_ENTRIES ((SUM_JOURNAL_SIZE - 2) /\
>>> sizeof(struct nat_journal_entry))
>>> @@ -1348,7 +1350,7 @@ struct f2fs_summary_block {
>>> };
>>> #define F2FS_SUMMARY_BLOCK_JOURNAL(blk) ((struct f2fs_journal *)(&(blk)->entries[ENTRIES_IN_SUM]))
>>> #define F2FS_SUMMARY_BLOCK_FOOTER(blk) ((struct summary_footer *)&((char *)\
>>> - (&(blk)->entries[0]))[F2FS_BLKSIZE - SUM_FOOTER_SIZE])
>>> + (&(blk)->entries[0]))[F2FS_SUM_BLKSIZE - SUM_FOOTER_SIZE])
>>>
>>> /*
>>> * For directory operations
>>> @@ -1711,6 +1713,8 @@ extern int dev_fill_block(void *, __u64, enum rw_hint);
>>>
>>> extern int dev_read_block(void *, __u64);
>>> extern int dev_reada_block(__u64);
>>> +extern int dev_write_4k_block(void *, __u64, __u32, enum rw_hint);
>>> +extern int dev_read_4k_block(void *, __u64, __u32);
>>>
>>> extern int dev_read_version(void *, __u64, size_t);
>>> extern void get_kernel_version(__u8 *);
>>> @@ -2022,6 +2026,7 @@ struct feature feature_table[] = { \
>>> { "compression", F2FS_FEATURE_COMPRESSION, 1}, \
>>> { "ro", F2FS_FEATURE_RO, 1}, \
>>> { "device_alias", F2FS_FEATURE_DEVICE_ALIAS, 0}, \
>>> + { "packed_ssa", F2FS_FEATURE_PACKED_SSA, 1}, \
>>
>> ^
>> IIUC, this feature can not be tunned by fsck? since it will change the disk layout?
> > We need to turn on/off with the mkfs option. Can we set/clear in
> superblock with fsck?
Oh, I missed to check tune_sb_features(), fsck can only set encrypt/casefold feature
rather than all features w/ settable field == 1.
Thanks,
>
>>
>> Thanks,
>>
>>> { NULL, 0x0, 0}, \
>>> };
>>>
>>> @@ -2161,18 +2166,18 @@ static inline void check_block_struct_sizes(void)
>>> assert(sizeof(struct f2fs_summary) * ENTRIES_IN_SUM
>>> + offsetof(struct f2fs_journal, nat_j)
>>> + NAT_JOURNAL_ENTRIES * sizeof(struct nat_journal_entry)
>>> - + NAT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_BLKSIZE);
>>> + + NAT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_SUM_BLKSIZE);
>>>
>>> /* Check SIT Journal Block Size */
>>> assert(sizeof(struct f2fs_summary) * ENTRIES_IN_SUM
>>> + offsetof(struct f2fs_journal, sit_j)
>>> + SIT_JOURNAL_ENTRIES * sizeof(struct sit_journal_entry)
>>> - + SIT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_BLKSIZE);
>>> + + SIT_JOURNAL_RESERVED + sizeof(struct summary_footer) == F2FS_SUM_BLKSIZE);
>>>
>>> /* Check Info Journal Block Size */
>>> assert(sizeof(struct f2fs_summary) * ENTRIES_IN_SUM + sizeof(__le64)
>>> + offsetof(struct f2fs_journal, info)
>>> - + EXTRA_INFO_RESERVED + sizeof(struct summary_footer) == F2FS_BLKSIZE);
>>> + + EXTRA_INFO_RESERVED + sizeof(struct summary_footer) == F2FS_SUM_BLKSIZE);
>>>
>>> /* Check Dentry Block Size */
>>> assert(sizeof(__u8) * (SIZE_OF_DENTRY_BITMAP + SIZE_OF_RESERVED)
>>> diff --git a/lib/libf2fs_io.c b/lib/libf2fs_io.c
>>> index c31f3b8..deafc4f 100644
>>> --- a/lib/libf2fs_io.c
>>> +++ b/lib/libf2fs_io.c
>>> @@ -734,6 +734,18 @@ int dev_reada_block(__u64 blk_addr)
>>> return dev_readahead(blk_addr << F2FS_BLKSIZE_BITS, F2FS_BLKSIZE);
>>> }
>>>
>>> +int dev_write_4k_block(void *buf, __u64 blk_addr, __u32 offset, enum rw_hint whint)
>>> +{
>>> + return dev_write(buf, (blk_addr << F2FS_BLKSIZE_BITS) + offset * 4096,
>>> + 4096, whint);
>>> +}
>>> +
>>> +int dev_read_4k_block(void *buf, __u64 blk_addr, __u32 offset)
>>> +{
>>> + return dev_read(buf, (blk_addr << F2FS_BLKSIZE_BITS) + offset * 4096,
>>> + 4096);
>>> +}
>>> +
>>> int f2fs_fsync_device(void)
>>> {
>>> #ifdef HAVE_FSYNC
>>> diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
>>> index d05e897..b3dccd0 100644
>>> --- a/mkfs/f2fs_format.c
>>> +++ b/mkfs/f2fs_format.c
>>> @@ -500,8 +500,16 @@ static int f2fs_prepare_super_block(void)
>>> if (c.feature & F2FS_FEATURE_RO) {
>>> blocks_for_ssa = 0;
>>> } else {
>>> + unsigned int ssa_per_block;
>>> +
>>> ASSERT((total_valid_blks_available % c.blks_per_seg) == 0);
>>> - blocks_for_ssa = total_valid_blks_available / c.blks_per_seg;
>>> + if (c.feature & F2FS_FEATURE_PACKED_SSA) {
>>> + ssa_per_block = c.blksize / F2FS_SUM_BLKSIZE;
>>> + blocks_for_ssa = round_up(total_valid_blks_available /
>>> + c.blks_per_seg, ssa_per_block);
>>> + } else {
>>> + blocks_for_ssa = total_valid_blks_available / c.blks_per_seg;
>>> + }
>>> }
>>>
>>> set_sb(segment_count_ssa, SEG_ALIGN(blocks_for_ssa));
>>> diff --git a/mkfs/f2fs_format_main.c b/mkfs/f2fs_format_main.c
>>> index 8f8e975..8d44a9b 100644
>>> --- a/mkfs/f2fs_format_main.c
>>> +++ b/mkfs/f2fs_format_main.c
>>> @@ -380,6 +380,12 @@ static void f2fs_parse_options(int argc, char *argv[])
>>> }
>>> }
>>>
>>> + if ((c.feature & F2FS_FEATURE_PACKED_SSA) &&
>>> + (c.blksize == F2FS_MIN_BLKSIZE)) {
>>> + c.feature &= ~F2FS_FEATURE_PACKED_SSA;
>>> + MSG(0, "\tInfo: packed_ssa feature is disabled for 4k block.\n");
>>> + }
>>> +
>>> if (optind >= argc) {
>>> MSG(0, "\tError: Device not specified\n");
>>> mkfs_usage();
>>
next prev parent reply other threads:[~2025-12-23 2:34 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-21 3:23 [f2fs-dev] [PATCH v5] f2fs-tools: revert summary entry count from 2048 to 512 in 16kb block support Daeho Jeong
2025-12-21 3:23 ` Daeho Jeong
2025-12-22 9:27 ` [f2fs-dev] " Chao Yu via Linux-f2fs-devel
2025-12-22 9:27 ` Chao Yu
2025-12-22 16:09 ` Daeho Jeong
2025-12-22 16:09 ` Daeho Jeong
2025-12-23 2:33 ` Chao Yu via Linux-f2fs-devel [this message]
2025-12-23 2:33 ` Chao Yu
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