From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F39DE23AB87 for ; Tue, 28 Oct 2025 02:20:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761618045; cv=none; b=goJWtmZYuxqoHIiJ48/lgnunI89PM2R/Ii766WzmOhH/H8yV3F5FORmxFlaJTOm6di+NZwNtHbjCAZP10om0l/t+0VHYbZxau3W24ulwUw338YbcH1Tg2WU8is/uKfEBUx++o8WrHUpcN6xkuOQGMNfqFJP2RtQkH7r4YgwzPrw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761618045; c=relaxed/simple; bh=ZDhmCCOy41SkIigspduwC5nHq3r2GD2OjyI4hJTKuO4=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=SatWFps+8mdHbdfK82f/4p542j4/Cqdwa9MSe2knko3M5STBk5fNozZaM9iOvdrBebbtOdvybI3P1IVktHRTCybZ+GNaujSXpwEK3Q2X3HOJNeS08H5uTqWNVZ5QnCscz82LpDe54Sy/JFvLNZZQCMWC16dEaH+o3Y3YYKc7qNg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W9WXVvbv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="W9WXVvbv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BC6EC4CEF1; Tue, 28 Oct 2025 02:20:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761618044; bh=ZDhmCCOy41SkIigspduwC5nHq3r2GD2OjyI4hJTKuO4=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=W9WXVvbvzGUdeBRwLQ/jFPFPbQJikDBYa2HbrnF9SvjNb5ocPbUi0T9l9Vf3TdZAH R9WJph2M3CQfYgmffF9uhSyo+pkqDXzK5iciwuz+iVEPAZtB1uiGwcwbdosY5FLDMl LsMvzvIiMKytAtApa3Im651WicruBnvLiOGwx3BHsn5iysIz3z8i8UNWD1NkD3qyet 4jDy7RANlkgi1WKnp70ayaAtYOIzm8MMagDwimc5GWssWgY9fVoWrSzUKxxDCOLJE9 EpH7Lbjvr98zxATUbdKa6LMKtNaXgFht4mx87IWmWZUeeTFYjMrXUqoE7AFn/5l4fK uBKbsJjJibl6A== Message-ID: Date: Tue, 28 Oct 2025 10:20:40 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, Daeho Jeong Subject: Re: [f2fs-dev] [PATCH v4] f2fs: revert summary entry count from 2048 to 512 in 16kb block support To: Daeho Jeong , linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com References: <20251027193707.4089180-1-daeho43@gmail.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20251027193707.4089180-1-daeho43@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/28/25 03:37, Daeho Jeong wrote: > From: Daeho Jeong > > 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: d7e9a9037de2 ("f2fs: Support Block Size == Page Size") > Signed-off-by: Daeho Jeong > --- > v4: add a feature to prevent from mounting deprecated format > v3: error handling for a failure of f2fs_get_meta_folio(). > v2: detect legacy layout and prevent mount. > --- > fs/f2fs/f2fs.h | 1 + > fs/f2fs/gc.c | 117 +++++++++++++++++++++++----------------- > fs/f2fs/recovery.c | 2 +- > fs/f2fs/segment.c | 29 ++++++---- > fs/f2fs/segment.h | 8 ++- > fs/f2fs/super.c | 14 +++++ > include/linux/f2fs_fs.h | 5 +- > 7 files changed, 113 insertions(+), 63 deletions(-) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index b6e35fdd5fd3..b4eac9a6e5ae 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -245,6 +245,7 @@ struct f2fs_mount_info { > #define F2FS_FEATURE_COMPRESSION 0x00002000 > #define F2FS_FEATURE_RO 0x00004000 > #define F2FS_FEATURE_DEVICE_ALIAS 0x00008000 > +#define F2FS_FEATURE_PACKED_SSA 0x00010000 So, we'd better to add related sysfs entries in below directories, right? - /sys/fs/f2fs/features/ - /sys/fs/f2fs//feature_list/ Thanks, > > #define __F2FS_HAS_FEATURE(raw_super, mask) \ > ((raw_super->feature & cpu_to_le32(mask)) != 0) > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > index 8abf521530ff..af2f4d28462c 100644 > --- a/fs/f2fs/gc.c > +++ b/fs/f2fs/gc.c > @@ -1732,7 +1732,7 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > unsigned char type = IS_DATASEG(get_seg_entry(sbi, segno)->type) ? > SUM_TYPE_DATA : SUM_TYPE_NODE; > unsigned char data_type = (type == SUM_TYPE_DATA) ? DATA : NODE; > - int submitted = 0; > + int submitted = 0, sum_blk_cnt; > > if (__is_large_section(sbi)) { > sec_end_segno = rounddown(end_segno, SEGS_PER_SEC(sbi)); > @@ -1766,22 +1766,28 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > > sanity_check_seg_type(sbi, get_seg_entry(sbi, segno)->type); > > + segno = rounddown(segno, SUMS_PER_BLOCK); > + sum_blk_cnt = DIV_ROUND_UP(end_segno - segno, SUMS_PER_BLOCK); > /* readahead multi ssa blocks those have contiguous address */ > if (__is_large_section(sbi)) > f2fs_ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno), > - end_segno - segno, META_SSA, true); > + sum_blk_cnt, META_SSA, true); > > /* reference all summary page */ > while (segno < end_segno) { > - struct folio *sum_folio = f2fs_get_sum_folio(sbi, segno++); > + struct folio *sum_folio = f2fs_get_sum_folio(sbi, segno); > + > + segno += SUMS_PER_BLOCK; > if (IS_ERR(sum_folio)) { > int err = PTR_ERR(sum_folio); > > - end_segno = segno - 1; > - for (segno = start_segno; segno < end_segno; segno++) { > + end_segno = segno - SUMS_PER_BLOCK; > + segno = rounddown(start_segno, SUMS_PER_BLOCK); > + while (segno < end_segno) { > sum_folio = filemap_get_folio(META_MAPPING(sbi), > GET_SUM_BLOCK(sbi, segno)); > folio_put_refs(sum_folio, 2); > + segno += SUMS_PER_BLOCK; > } > return err; > } > @@ -1790,68 +1796,83 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > > blk_start_plug(&plug); > > - for (segno = start_segno; segno < end_segno; segno++) { > - struct f2fs_summary_block *sum; > + segno = start_segno; > + while (segno < end_segno) { > + unsigned int cur_segno; > > /* find segment summary of victim */ > struct folio *sum_folio = filemap_get_folio(META_MAPPING(sbi), > GET_SUM_BLOCK(sbi, segno)); > + unsigned int block_end_segno = rounddown(segno, SUMS_PER_BLOCK) > + + SUMS_PER_BLOCK; > + > + if (block_end_segno > end_segno) > + block_end_segno = end_segno; > > if (is_cursec(sbi, GET_SEC_FROM_SEG(sbi, segno))) { > f2fs_err(sbi, "%s: segment %u is used by log", > __func__, segno); > f2fs_bug_on(sbi, 1); > - goto skip; > + goto next_block; > } > > - if (get_valid_blocks(sbi, segno, false) == 0) > - goto freed; > - if (gc_type == BG_GC && __is_large_section(sbi) && > - migrated >= sbi->migration_granularity) > - goto skip; > if (!folio_test_uptodate(sum_folio) || > unlikely(f2fs_cp_error(sbi))) > - goto skip; > + goto next_block; > > - sum = folio_address(sum_folio); > - if (type != GET_SUM_TYPE((&sum->footer))) { > - f2fs_err(sbi, "Inconsistent segment (%u) type [%d, %d] in SIT and SSA", > - segno, type, GET_SUM_TYPE((&sum->footer))); > - f2fs_stop_checkpoint(sbi, false, > - STOP_CP_REASON_CORRUPTED_SUMMARY); > - goto skip; > - } > + for (cur_segno = segno; cur_segno < block_end_segno; > + cur_segno++) { > + struct f2fs_summary_block *sum; > > - /* > - * this is to avoid deadlock: > - * - lock_page(sum_page) - f2fs_replace_block > - * - check_valid_map() - down_write(sentry_lock) > - * - down_read(sentry_lock) - change_curseg() > - * - lock_page(sum_page) > - */ > - if (type == SUM_TYPE_NODE) > - submitted += gc_node_segment(sbi, sum->entries, segno, > - gc_type); > - else > - submitted += gc_data_segment(sbi, sum->entries, gc_list, > - segno, gc_type, > - force_migrate); > + if (get_valid_blocks(sbi, cur_segno, false) == 0) > + goto freed; > + if (gc_type == BG_GC && __is_large_section(sbi) && > + migrated >= sbi->migration_granularity) > + continue; > > - stat_inc_gc_seg_count(sbi, data_type, gc_type); > - sbi->gc_reclaimed_segs[sbi->gc_mode]++; > - migrated++; > + sum = SUM_BLK_PAGE_ADDR(sum_folio, cur_segno); > + if (type != GET_SUM_TYPE((&sum->footer))) { > + f2fs_err(sbi, "Inconsistent segment (%u) type " > + "[%d, %d] in SSA and SIT", > + cur_segno, type, > + GET_SUM_TYPE((&sum->footer))); > + f2fs_stop_checkpoint(sbi, false, > + STOP_CP_REASON_CORRUPTED_SUMMARY); > + continue; > + } > > -freed: > - if (gc_type == FG_GC && > - get_valid_blocks(sbi, segno, false) == 0) > - seg_freed++; > + /* > + * this is to avoid deadlock: > + * - lock_page(sum_page) - f2fs_replace_block > + * - check_valid_map() - down_write(sentry_lock) > + * - down_read(sentry_lock) - change_curseg() > + * - lock_page(sum_page) > + */ > + if (type == SUM_TYPE_NODE) > + submitted += gc_node_segment(sbi, sum->entries, > + cur_segno, gc_type); > + else > + submitted += gc_data_segment(sbi, sum->entries, > + gc_list, cur_segno, > + gc_type, force_migrate); > > - if (__is_large_section(sbi)) > - sbi->next_victim_seg[gc_type] = > - (segno + 1 < sec_end_segno) ? > - segno + 1 : NULL_SEGNO; > -skip: > + stat_inc_gc_seg_count(sbi, data_type, gc_type); > + sbi->gc_reclaimed_segs[sbi->gc_mode]++; > + migrated++; > + > +freed: > + if (gc_type == FG_GC && > + get_valid_blocks(sbi, cur_segno, false) == 0) > + seg_freed++; > + > + if (__is_large_section(sbi)) > + sbi->next_victim_seg[gc_type] = > + (cur_segno + 1 < sec_end_segno) ? > + cur_segno + 1 : NULL_SEGNO; > + } > +next_block: > folio_put_refs(sum_folio, 2); > + segno = block_end_segno; > } > > if (submitted) > diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c > index 215e442db72c..af72309b9bfc 100644 > --- a/fs/f2fs/recovery.c > +++ b/fs/f2fs/recovery.c > @@ -519,7 +519,7 @@ static int check_index_in_prev_nodes(struct f2fs_sb_info *sbi, > sum_folio = f2fs_get_sum_folio(sbi, segno); > if (IS_ERR(sum_folio)) > return PTR_ERR(sum_folio); > - sum_node = folio_address(sum_folio); > + sum_node = SUM_BLK_PAGE_ADDR(sum_folio, segno); > sum = sum_node->entries[blkoff]; > f2fs_folio_put(sum_folio, true); > got_it: > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index b45eace879d7..77aa2125b8ca 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -2712,7 +2712,10 @@ struct folio *f2fs_get_sum_folio(struct f2fs_sb_info *sbi, unsigned int segno) > void f2fs_update_meta_page(struct f2fs_sb_info *sbi, > void *src, block_t blk_addr) > { > - struct folio *folio = f2fs_grab_meta_folio(sbi, blk_addr); > + struct folio *folio = f2fs_get_meta_folio_retry(sbi, blk_addr); > + > + if (IS_ERR(folio)) > + return; > > memcpy(folio_address(folio), src, PAGE_SIZE); > folio_mark_dirty(folio); > @@ -2720,9 +2723,17 @@ void f2fs_update_meta_page(struct f2fs_sb_info *sbi, > } > > static void write_sum_page(struct f2fs_sb_info *sbi, > - struct f2fs_summary_block *sum_blk, block_t blk_addr) > + struct f2fs_summary_block *sum_blk, unsigned int segno) > { > - f2fs_update_meta_page(sbi, (void *)sum_blk, blk_addr); > + struct folio *folio; > + > + folio = f2fs_get_sum_folio(sbi, segno); > + if (IS_ERR(folio)) > + return; > + > + memcpy(SUM_BLK_PAGE_ADDR(folio, segno), sum_blk, sizeof(*sum_blk)); > + folio_mark_dirty(folio); > + f2fs_folio_put(folio, true); > } > > static void write_current_sum_page(struct f2fs_sb_info *sbi, > @@ -2987,7 +2998,7 @@ static int new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec) > int ret; > > if (curseg->inited) > - write_sum_page(sbi, curseg->sum_blk, GET_SUM_BLOCK(sbi, segno)); > + write_sum_page(sbi, curseg->sum_blk, segno); > > segno = __get_next_segno(sbi, type); > ret = get_new_segment(sbi, &segno, new_sec, pinning); > @@ -3046,7 +3057,7 @@ static int change_curseg(struct f2fs_sb_info *sbi, int type) > struct folio *sum_folio; > > if (curseg->inited) > - write_sum_page(sbi, curseg->sum_blk, GET_SUM_BLOCK(sbi, curseg->segno)); > + write_sum_page(sbi, curseg->sum_blk, curseg->segno); > > __set_test_and_inuse(sbi, new_segno); > > @@ -3065,7 +3076,7 @@ static int change_curseg(struct f2fs_sb_info *sbi, int type) > memset(curseg->sum_blk, 0, SUM_ENTRY_SIZE); > return PTR_ERR(sum_folio); > } > - sum_node = folio_address(sum_folio); > + sum_node = SUM_BLK_PAGE_ADDR(sum_folio, new_segno); > memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE); > f2fs_folio_put(sum_folio, true); > return 0; > @@ -3154,8 +3165,7 @@ static void __f2fs_save_inmem_curseg(struct f2fs_sb_info *sbi, int type) > goto out; > > if (get_valid_blocks(sbi, curseg->segno, false)) { > - write_sum_page(sbi, curseg->sum_blk, > - GET_SUM_BLOCK(sbi, curseg->segno)); > + write_sum_page(sbi, curseg->sum_blk, curseg->segno); > } else { > mutex_lock(&DIRTY_I(sbi)->seglist_lock); > __set_test_and_free(sbi, curseg->segno, true); > @@ -3833,8 +3843,7 @@ int f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct folio *folio, > if (segment_full) { > if (type == CURSEG_COLD_DATA_PINNED && > !((curseg->segno + 1) % sbi->segs_per_sec)) { > - write_sum_page(sbi, curseg->sum_blk, > - GET_SUM_BLOCK(sbi, curseg->segno)); > + write_sum_page(sbi, curseg->sum_blk, curseg->segno); > reset_curseg_fields(curseg); > goto skip_new_segment; > } > diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h > index 1ce2c8abaf48..e883f14c228f 100644 > --- a/fs/f2fs/segment.h > +++ b/fs/f2fs/segment.h > @@ -85,8 +85,12 @@ static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi, > #define GET_ZONE_FROM_SEG(sbi, segno) \ > GET_ZONE_FROM_SEC(sbi, GET_SEC_FROM_SEG(sbi, segno)) > > -#define GET_SUM_BLOCK(sbi, segno) \ > - ((sbi)->sm_info->ssa_blkaddr + (segno)) > +#define SUMS_PER_BLOCK (F2FS_BLKSIZE / F2FS_SUM_BLKSIZE) > +#define GET_SUM_BLOCK(sbi, segno) \ > + (SM_I(sbi)->ssa_blkaddr + (segno / SUMS_PER_BLOCK)) > +#define GET_SUM_BLKOFF(segno) (segno % SUMS_PER_BLOCK) > +#define SUM_BLK_PAGE_ADDR(folio, segno) \ > + (folio_address(folio) + GET_SUM_BLKOFF(segno) * F2FS_SUM_BLKSIZE) > > #define GET_SUM_TYPE(footer) ((footer)->entry_type) > #define SET_SUM_TYPE(footer, type) ((footer)->entry_type = (type)) > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c > index 6e52e36c1f1a..707e24551fdd 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -4052,6 +4052,20 @@ static int sanity_check_raw_super(struct f2fs_sb_info *sbi, > if (sanity_check_area_boundary(sbi, folio, index)) > return -EFSCORRUPTED; > > + /* > + * Check for legacy summary layout on 16KB+ block devices. > + * Modern f2fs-tools packs multiple 4KB summary areas into one block, > + * whereas legacy versions used one block per summary, leading > + * to a much larger SSA. > + */ > + if (SUMS_PER_BLOCK > 1 && > + !(__F2FS_HAS_FEATURE(raw_super, F2FS_FEATURE_PACKED_SSA))) { > + f2fs_info(sbi, "Error: Device formatted with a legacy version. " > + "Please reformat with a tool supporting the packed ssa " > + "feature for block sizes larger than 4kb."); > + return -EOPNOTSUPP; > + } > + > return 0; > } > > diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h > index 6afb4a13b81d..a7880787cad3 100644 > --- a/include/linux/f2fs_fs.h > +++ b/include/linux/f2fs_fs.h > @@ -17,6 +17,7 @@ > #define F2FS_LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9) /* log number for sector/blk */ > #define F2FS_BLKSIZE PAGE_SIZE /* support only block == page */ > #define F2FS_BLKSIZE_BITS PAGE_SHIFT /* bits for F2FS_BLKSIZE */ > +#define F2FS_SUM_BLKSIZE 4096 /* only support 4096 byte sum block */ > #define F2FS_MAX_EXTENSION 64 /* # of extension entries */ > #define F2FS_EXTENSION_LEN 8 /* max size of extension */ > > @@ -441,7 +442,7 @@ 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 f2fs_summary) */ > #define SUM_FOOTER_SIZE (5) /* sizeof(struct summary_footer) */ > #define SUM_ENTRY_SIZE (SUMMARY_SIZE * ENTRIES_IN_SUM) > @@ -467,7 +468,7 @@ struct summary_footer { > __le32 check_sum; /* summary checksum */ > } __packed; > > -#define SUM_JOURNAL_SIZE (F2FS_BLKSIZE - SUM_FOOTER_SIZE -\ > +#define SUM_JOURNAL_SIZE (F2FS_SUM_BLKSIZE - SUM_FOOTER_SIZE -\ > SUM_ENTRY_SIZE) > #define NAT_JOURNAL_ENTRIES ((SUM_JOURNAL_SIZE - 2) /\ > sizeof(struct nat_journal_entry))