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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: BCD4F1A0005 X-Stat-Signature: 1dghbu958dja8ceirkpgqaqqdend9byd X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1763707831-714256 X-HE-Meta: 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 p4NfaK8g 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Nov 21, 2025 at 01:48:46AM +0000, Jaegeuk Kim wrote: > This patch adds a sysfs entry to change the folio order for readahead. You'll need to explain why this is useful. And why this is f2fs specific instead of generic. > > Signed-off-by: Jaegeuk Kim > --- > fs/f2fs/data.c | 1 + > fs/f2fs/f2fs.h | 3 +++ > fs/f2fs/super.c | 1 + > fs/f2fs/sysfs.c | 9 +++++++++ > 4 files changed, 14 insertions(+) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index c80d7960b652..faf1faa27c41 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -2764,6 +2764,7 @@ int f2fs_readahead_pages(struct file *file, loff_t offset, loff_t len) > while (nrpages) { > unsigned long this_chunk = min(nrpages, ra_pages); > > + ractl.ra->desired_order = F2FS_I_SB(inode)->ra_folio_order; > ractl.ra->ra_pages = this_chunk; > > page_cache_sync_ra(&ractl, this_chunk << 1); > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 934287cc5624..0e61e253d861 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -1921,6 +1921,9 @@ struct f2fs_sb_info { > /* carve out reserved_blocks from total blocks */ > bool carve_out; > > + /* enable large folio. */ > + unsigned int ra_folio_order; > + > #ifdef CONFIG_F2FS_FS_COMPRESSION > struct kmem_cache *page_array_slab; /* page array entry */ > unsigned int page_array_slab_size; /* default page array slab size */ > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c > index d47ec718f3be..dabac6f288f0 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -4287,6 +4287,7 @@ static void init_sb_info(struct f2fs_sb_info *sbi) > NAT_ENTRY_PER_BLOCK)); > sbi->allocate_section_hint = le32_to_cpu(raw_super->section_count); > sbi->allocate_section_policy = ALLOCATE_FORWARD_NOHINT; > + sbi->ra_folio_order = 0; > F2FS_ROOT_INO(sbi) = le32_to_cpu(raw_super->root_ino); > F2FS_NODE_INO(sbi) = le32_to_cpu(raw_super->node_ino); > F2FS_META_INO(sbi) = le32_to_cpu(raw_super->meta_ino); > diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c > index c42f4f979d13..2537a25986a6 100644 > --- a/fs/f2fs/sysfs.c > +++ b/fs/f2fs/sysfs.c > @@ -906,6 +906,13 @@ static ssize_t __sbi_store(struct f2fs_attr *a, > return count; > } > > + if (!strcmp(a->attr.name, "ra_folio_order")) { > + if (t < 0 || t > MAX_PAGECACHE_ORDER) > + return -EINVAL; > + sbi->ra_folio_order = t; > + return count; > + } > + > *ui = (unsigned int)t; > > return count; > @@ -1180,6 +1187,7 @@ F2FS_SBI_GENERAL_RW_ATTR(migration_window_granularity); > F2FS_SBI_GENERAL_RW_ATTR(dir_level); > F2FS_SBI_GENERAL_RW_ATTR(allocate_section_hint); > F2FS_SBI_GENERAL_RW_ATTR(allocate_section_policy); > +F2FS_SBI_GENERAL_RW_ATTR(ra_folio_order); > #ifdef CONFIG_F2FS_IOSTAT > F2FS_SBI_GENERAL_RW_ATTR(iostat_enable); > F2FS_SBI_GENERAL_RW_ATTR(iostat_period_ms); > @@ -1422,6 +1430,7 @@ static struct attribute *f2fs_attrs[] = { > ATTR_LIST(reserved_pin_section), > ATTR_LIST(allocate_section_hint), > ATTR_LIST(allocate_section_policy), > + ATTR_LIST(ra_folio_order), > NULL, > }; > ATTRIBUTE_GROUPS(f2fs); > -- > 2.52.0.487.g5c8c507ade-goog > > ---end quoted text---