Re: [PATCH 10/10] btrfs: rename io_ctl page helpers to folio helpers

From: Tal Zussman

Date: Sun Sep 06 2026 - 20:58:50 EST

On 9/7/26 3:23 AM, Qu Wenruo wrote:
> 在 2026/9/7 08:50, Tal Zussman 写道:
>> On 9/7/26 2:12 AM, Qu Wenruo wrote:
>>> 在 2026/9/7 07:59, Tal Zussman 写道:
>>>> These functions now operate on folios. Rename them and update comments
>>>> accordingly.
>>>
>>> Again, v1 space cache is fully disabled since commit 545e560a5b0f
>>> ("btrfs: disable v1 space cache"), it would make more sense to remove
>>> those functions other than doing a rename for codes that we're going to
>>> remove anyway.
>>>
>>
>> No problem, I can drop this and patch 8. I wasn't sure what the removal
>> timeline looked like and wanted to keep things consistent.
>
> Would appreciate a lot if you are also interested in removing those v1
> space cache code.
>

Sure, I can do that. So patches 8-10 can be dropped from this series and
I'll send another one removing the v1 space cache support.

>>
>>>>
>>>> Signed-off-by: Tal Zussman <tz2294@xxxxxxxxxxxx>
>>>> ---
>>>> fs/btrfs/free-space-cache.c | 78 ++++++++++++++++++++++-----------------------
>>>> 1 file changed, 39 insertions(+), 39 deletions(-)
>>>>
>>>> diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
>>>> index ab933ee6f19c..73cfc1d1a5c1 100644
>>>> --- a/fs/btrfs/free-space-cache.c
>>>> +++ b/fs/btrfs/free-space-cache.c
>>>> @@ -406,7 +406,7 @@ static void io_ctl_free(struct btrfs_io_ctl *io_ctl)
>>>> io_ctl->folios = NULL;
>>>> }
>>>>
>>>> -static void io_ctl_unmap_page(struct btrfs_io_ctl *io_ctl)
>>>> +static void io_ctl_unmap_folio(struct btrfs_io_ctl *io_ctl)
>>>> {
>>>> if (io_ctl->cur) {
>>>> io_ctl->cur = NULL;
>>>> @@ -414,7 +414,7 @@ static void io_ctl_unmap_page(struct btrfs_io_ctl *io_ctl)
>>>> }
>>>> }
>>>>
>>>> -static void io_ctl_map_page(struct btrfs_io_ctl *io_ctl, int clear)
>>>> +static void io_ctl_map_folio(struct btrfs_io_ctl *io_ctl, int clear)
>>>> {
>>>> ASSERT(io_ctl->index < io_ctl->num_folios);
>>>> io_ctl->folio = io_ctl->folios[io_ctl->index++];
>>>> @@ -425,11 +425,11 @@ static void io_ctl_map_page(struct btrfs_io_ctl *io_ctl, int clear)
>>>> clear_page(io_ctl->cur);
>>>> }
>>>>
>>>> -static void io_ctl_drop_pages(struct btrfs_io_ctl *io_ctl)
>>>> +static void io_ctl_drop_folios(struct btrfs_io_ctl *io_ctl)
>>>> {
>>>> int i;
>>>>
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>>
>>>> for (i = 0; i < io_ctl->num_folios; i++) {
>>>> if (io_ctl->folios[i]) {
>>>> @@ -439,7 +439,7 @@ static void io_ctl_drop_pages(struct btrfs_io_ctl *io_ctl)
>>>> }
>>>> }
>>>>
>>>> -static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate)
>>>> +static int io_ctl_prepare_folios(struct btrfs_io_ctl *io_ctl, bool uptodate)
>>>> {
>>>> struct folio *folio;
>>>> struct inode *inode = io_ctl->inode;
>>>> @@ -453,7 +453,7 @@ static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate)
>>>> FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
>>>> mask);
>>>> if (IS_ERR(folio)) {
>>>> - io_ctl_drop_pages(io_ctl);
>>>> + io_ctl_drop_folios(io_ctl);
>>>> return PTR_ERR(folio);
>>>> }
>>>>
>>>> @@ -461,7 +461,7 @@ static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate)
>>>> if (ret < 0) {
>>>> folio_unlock(folio);
>>>> folio_put(folio);
>>>> - io_ctl_drop_pages(io_ctl);
>>>> + io_ctl_drop_folios(io_ctl);
>>>> return ret;
>>>> }
>>>>
>>>> @@ -472,13 +472,13 @@ static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate)
>>>> if (folio->mapping != inode->i_mapping) {
>>>> btrfs_err(BTRFS_I(inode)->root->fs_info,
>>>> "free space cache page truncated");
>>>> - io_ctl_drop_pages(io_ctl);
>>>> + io_ctl_drop_folios(io_ctl);
>>>> return -EIO;
>>>> }
>>>> if (!folio_test_uptodate(folio)) {
>>>> btrfs_err(BTRFS_I(inode)->root->fs_info,
>>>> "error reading free space cache");
>>>> - io_ctl_drop_pages(io_ctl);
>>>> + io_ctl_drop_folios(io_ctl);
>>>> return -EIO;
>>>> }
>>>> }
>>>> @@ -492,7 +492,7 @@ static int io_ctl_prepare_pages(struct btrfs_io_ctl *io_ctl, bool uptodate)
>>>>
>>>> static void io_ctl_set_generation(struct btrfs_io_ctl *io_ctl, u64 generation)
>>>> {
>>>> - io_ctl_map_page(io_ctl, 1);
>>>> + io_ctl_map_folio(io_ctl, 1);
>>>>
>>>> /*
>>>> * Skip the csum areas. If we don't check crcs then we just have a
>>>> @@ -521,7 +521,7 @@ static int io_ctl_check_generation(struct btrfs_io_ctl *io_ctl, u64 generation)
>>>> btrfs_err_rl(io_ctl->fs_info,
>>>> "space cache generation (%llu) does not match inode (%llu)",
>>>> cache_gen, generation);
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>> return -EIO;
>>>> }
>>>> io_ctl->cur += sizeof(u64);
>>>> @@ -539,7 +539,7 @@ static void io_ctl_set_crc(struct btrfs_io_ctl *io_ctl, int index)
>>>>
>>>> crc = crc32c(crc, io_ctl->orig + offset, PAGE_SIZE - offset);
>>>> btrfs_crc32c_final(crc, (u8 *)&crc);
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>> tmp = folio_address(io_ctl->folios[0]);
>>>> tmp += index;
>>>> *tmp = crc;
>>>> @@ -561,13 +561,13 @@ static int io_ctl_check_crc(struct btrfs_io_ctl *io_ctl, int index)
>>>> tmp += index;
>>>> val = *tmp;
>>>>
>>>> - io_ctl_map_page(io_ctl, 0);
>>>> + io_ctl_map_folio(io_ctl, 0);
>>>> crc = crc32c(crc, io_ctl->orig + offset, PAGE_SIZE - offset);
>>>> btrfs_crc32c_final(crc, (u8 *)&crc);
>>>> if (val != crc) {
>>>> btrfs_err_rl(io_ctl->fs_info,
>>>> "csum mismatch on free space cache");
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>> return -EIO;
>>>> }
>>>>
>>>> @@ -595,12 +595,12 @@ static int io_ctl_add_entry(struct btrfs_io_ctl *io_ctl, u64 offset, u64 bytes,
>>>>
>>>> io_ctl_set_crc(io_ctl, io_ctl->index - 1);
>>>>
>>>> - /* No more pages to map */
>>>> + /* No more folios to map */
>>>> if (io_ctl->index >= io_ctl->num_folios)
>>>> return 0;
>>>>
>>>> - /* map the next page */
>>>> - io_ctl_map_page(io_ctl, 1);
>>>> + /* map the next folio */
>>>> + io_ctl_map_folio(io_ctl, 1);
>>>> return 0;
>>>> }
>>>>
>>>> @@ -610,24 +610,24 @@ static int io_ctl_add_bitmap(struct btrfs_io_ctl *io_ctl, void *bitmap)
>>>> return -ENOSPC;
>>>>
>>>> /*
>>>> - * If we aren't at the start of the current page, unmap this one and
>>>> + * If we aren't at the start of the current folio, unmap this one and
>>>> * map the next one if there is any left.
>>>> */
>>>> if (io_ctl->cur != io_ctl->orig) {
>>>> io_ctl_set_crc(io_ctl, io_ctl->index - 1);
>>>> if (io_ctl->index >= io_ctl->num_folios)
>>>> return -ENOSPC;
>>>> - io_ctl_map_page(io_ctl, 0);
>>>> + io_ctl_map_folio(io_ctl, 0);
>>>> }
>>>>
>>>> copy_page(io_ctl->cur, bitmap);
>>>> io_ctl_set_crc(io_ctl, io_ctl->index - 1);
>>>> if (io_ctl->index < io_ctl->num_folios)
>>>> - io_ctl_map_page(io_ctl, 0);
>>>> + io_ctl_map_folio(io_ctl, 0);
>>>> return 0;
>>>> }
>>>>
>>>> -static void io_ctl_zero_remaining_pages(struct btrfs_io_ctl *io_ctl)
>>>> +static void io_ctl_zero_remaining_folios(struct btrfs_io_ctl *io_ctl)
>>>> {
>>>> /*
>>>> * If we're not on the boundary we know we've modified the page and we
>>>> @@ -636,10 +636,10 @@ static void io_ctl_zero_remaining_pages(struct btrfs_io_ctl *io_ctl)
>>>> if (io_ctl->cur != io_ctl->orig)
>>>> io_ctl_set_crc(io_ctl, io_ctl->index - 1);
>>>> else
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>>
>>>> while (io_ctl->index < io_ctl->num_folios) {
>>>> - io_ctl_map_page(io_ctl, 1);
>>>> + io_ctl_map_folio(io_ctl, 1);
>>>> io_ctl_set_crc(io_ctl, io_ctl->index - 1);
>>>> }
>>>> }
>>>> @@ -666,7 +666,7 @@ static int io_ctl_read_entry(struct btrfs_io_ctl *io_ctl,
>>>> if (io_ctl->size >= sizeof(struct btrfs_free_space_entry))
>>>> return 0;
>>>>
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>>
>>>> return 0;
>>>> }
>>>> @@ -681,7 +681,7 @@ static int io_ctl_read_bitmap(struct btrfs_io_ctl *io_ctl,
>>>> return ret;
>>>>
>>>> copy_page(entry->bitmap, io_ctl->cur);
>>>> - io_ctl_unmap_page(io_ctl);
>>>> + io_ctl_unmap_folio(io_ctl);
>>>>
>>>> return 0;
>>>> }
>>>> @@ -797,7 +797,7 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
>>>>
>>>> readahead_cache(inode);
>>>>
>>>> - ret = io_ctl_prepare_pages(&io_ctl, true);
>>>> + ret = io_ctl_prepare_folios(&io_ctl, true);
>>>> if (ret)
>>>> goto out;
>>>>
>>>> @@ -869,7 +869,7 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
>>>> num_entries--;
>>>> }
>>>>
>>>> - io_ctl_unmap_page(&io_ctl);
>>>> + io_ctl_unmap_folio(&io_ctl);
>>>>
>>>> /*
>>>> * We add the bitmaps at the end of the entries in order that
>>>> @@ -882,13 +882,13 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
>>>> goto free_cache;
>>>> }
>>>>
>>>> - io_ctl_drop_pages(&io_ctl);
>>>> + io_ctl_drop_folios(&io_ctl);
>>>> ret = 1;
>>>> out:
>>>> io_ctl_free(&io_ctl);
>>>> return ret;
>>>> free_cache:
>>>> - io_ctl_drop_pages(&io_ctl);
>>>> + io_ctl_drop_folios(&io_ctl);
>>>>
>>>> spin_lock(&ctl->tree_lock);
>>>> __btrfs_remove_free_space_cache(ctl);
>>>> @@ -1280,7 +1280,7 @@ cleanup_write_cache_enospc(struct inode *inode,
>>>> struct btrfs_io_ctl *io_ctl,
>>>> struct extent_state **cached_state)
>>>> {
>>>> - io_ctl_drop_pages(io_ctl);
>>>> + io_ctl_drop_folios(io_ctl);
>>>> btrfs_unlock_extent(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1,
>>>> cached_state);
>>>> }
>>>> @@ -1297,7 +1297,7 @@ static int __btrfs_wait_cache_io(struct btrfs_root *root,
>>>> if (!inode)
>>>> return 0;
>>>>
>>>> - /* Flush the dirty pages in the cache file. */
>>>> + /* Flush the dirty folios in the cache file. */
>>>> ret = flush_dirty_cache(inode);
>>>> if (ret)
>>>> goto out;
>>>> @@ -1402,8 +1402,8 @@ static int __btrfs_write_out_cache(struct inode *inode,
>>>> spin_unlock(&block_group->lock);
>>>> }
>>>>
>>>> - /* Lock all pages first so we can lock the extent safely. */
>>>> - ret = io_ctl_prepare_pages(io_ctl, false);
>>>> + /* Lock all folios first so we can lock the extent safely. */
>>>> + ret = io_ctl_prepare_folios(io_ctl, false);
>>>> if (ret)
>>>> goto out_unlock;
>>>>
>>>> @@ -1443,10 +1443,10 @@ static int __btrfs_write_out_cache(struct inode *inode,
>>>> if (ret)
>>>> goto out_nospc;
>>>>
>>>> - /* Zero out the rest of the pages just to make sure */
>>>> - io_ctl_zero_remaining_pages(io_ctl);
>>>> + /* Zero out the rest of the folios just to make sure */
>>>> + io_ctl_zero_remaining_folios(io_ctl);
>>>>
>>>> - /* Everything is written out, now we dirty the pages in the file. */
>>>> + /* Everything is written out, now we dirty the folios in the file. */
>>>> i_size = i_size_read(inode);
>>>> for (int i = 0; i < round_up(i_size, PAGE_SIZE) / PAGE_SIZE; i++) {
>>>> u64 dirty_start = i * PAGE_SIZE;
>>>> @@ -1461,17 +1461,17 @@ static int __btrfs_write_out_cache(struct inode *inode,
>>>> if (block_group->flags & BTRFS_BLOCK_GROUP_DATA)
>>>> up_write(&block_group->data_rwsem);
>>>> /*
>>>> - * Release the pages and unlock the extent, we will flush
>>>> + * Release the folios and unlock the extent, we will flush
>>>> * them out later
>>>> */
>>>> - io_ctl_drop_pages(io_ctl);
>>>> + io_ctl_drop_folios(io_ctl);
>>>> io_ctl_free(io_ctl);
>>>>
>>>> btrfs_unlock_extent(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1,
>>>> &cached_state);
>>>>
>>>> /*
>>>> - * at this point the pages are under IO and we're happy,
>>>> + * at this point the folios are under IO and we're happy,
>>>> * The caller is responsible for waiting on them and updating
>>>> * the cache and the inode
>>>> */
>>>>
>>>
>>
>