On 2019/7/18 12:00, Jaegeuk Kim wrote:
> On 07/18, Chao Yu wrote:
>> On 2019/7/18 11:12, Jaegeuk Kim wrote:
>>> f2fs_allocate_data_block() invalidates old block address and enable new
>>> block
>>> address. Then, if we try to read old block by f2fs_submit_page_bio(), it
>>> will
>>> give WARN due to reading invalid blocks.
>>>
>>> Let's make the order sanely back.
>>
>> Hmm.. to avoid WARM, we may suffer one more memcpy, I suspect this can reduce
>> online resize or foreground gc ioctl performance...
>
> I worried about performance tho, more concern came to me that there may exist
> a
> chance that other thread can allocate and write something in old block
> address.
Me too, however, previous invalid block address should be reused after a
checkpoint, and checkpoint should have invalidated meta cache already, so there
shouldn't be any race here.
/*
* invalidate intermediate page cache borrowed from meta inode
* which are used for migration of encrypted inode's blocks.
*/
if (f2fs_sb_has_encrypt(sbi))
invalidate_mapping_pages(META_MAPPING(sbi),
MAIN_BLKADDR(sbi), MAX_BLKADDR(sbi) - 1);
Thanks,
>
>>
>> Can we just relief to use DATA_GENERIC_ENHANCE_READ for this case...?
>
> We need to keep consistency for this api.
>
> Thanks,
>
>>
>>>
>>> Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
>>
>> Except performance, I'm okay with this change.
>>
>> Reviewed-by: Chao Yu <yuch...@huawei.com>
>>
>> Thanks,
>>
>>> ---
>>> v2:
>>> I was fixing the comments. :)
>>>
>>> fs/f2fs/gc.c | 70 +++++++++++++++++++++++++---------------------------
>>> 1 file changed, 34 insertions(+), 36 deletions(-)
>>>
>>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>>> index 6691f526fa40..8974672db78f 100644
>>> --- a/fs/f2fs/gc.c
>>> +++ b/fs/f2fs/gc.c
>>> @@ -796,6 +796,29 @@ static int move_data_block(struct inode *inode,
>>> block_t bidx,
>>> if (lfs_mode)
>>> down_write(&fio.sbi->io_order_lock);
>>>
>>> + mpage = f2fs_grab_cache_page(META_MAPPING(fio.sbi),
>>> + fio.old_blkaddr, false);
>>> + if (!mpage)
>>> + goto up_out;
>>> +
>>> + fio.encrypted_page = mpage;
>>> +
>>> + /* read source block in mpage */
>>> + if (!PageUptodate(mpage)) {
>>> + err = f2fs_submit_page_bio(&fio);
>>> + if (err) {
>>> + f2fs_put_page(mpage, 1);
>>> + goto up_out;
>>> + }
>>> + lock_page(mpage);
>>> + if (unlikely(mpage->mapping != META_MAPPING(fio.sbi) ||
>>> + !PageUptodate(mpage))) {
>>> + err = -EIO;
>>> + f2fs_put_page(mpage, 1);
>>> + goto up_out;
>>> + }
>>> + }
>>> +
>>> f2fs_allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr,
>>> &sum, CURSEG_COLD_DATA, NULL, false);
>>>
>>> @@ -803,44 +826,18 @@ static int move_data_block(struct inode *inode,
>>> block_t bidx,
>>> newaddr, FGP_LOCK | FGP_CREAT, GFP_NOFS);
>>> if (!fio.encrypted_page) {
>>> err = -ENOMEM;
>>> - goto recover_block;
>>> - }
>>> -
>>> - mpage = f2fs_pagecache_get_page(META_MAPPING(fio.sbi),
>>> - fio.old_blkaddr, FGP_LOCK, GFP_NOFS);
>>> - if (mpage) {
>>> - bool updated = false;
>>> -
>>> - if (PageUptodate(mpage)) {
>>> - memcpy(page_address(fio.encrypted_page),
>>> - page_address(mpage), PAGE_SIZE);
>>> - updated = true;
>>> - }
>>> f2fs_put_page(mpage, 1);
>>> - invalidate_mapping_pages(META_MAPPING(fio.sbi),
>>> - fio.old_blkaddr, fio.old_blkaddr);
>>> - if (updated)
>>> - goto write_page;
>>> - }
>>> -
>>> - err = f2fs_submit_page_bio(&fio);
>>> - if (err)
>>> - goto put_page_out;
>>> -
>>> - /* write page */
>>> - lock_page(fio.encrypted_page);
>>> -
>>> - if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi))) {
>>> - err = -EIO;
>>> - goto put_page_out;
>>> - }
>>> - if (unlikely(!PageUptodate(fio.encrypted_page))) {
>>> - err = -EIO;
>>> - goto put_page_out;
>>> + goto recover_block;
>>> }
>>>
>>> -write_page:
>>> + /* write target block */
>>> f2fs_wait_on_page_writeback(fio.encrypted_page, DATA, true, true);
>>> + memcpy(page_address(fio.encrypted_page),
>>> + page_address(mpage), PAGE_SIZE);
>>> + f2fs_put_page(mpage, 1);
>>> + invalidate_mapping_pages(META_MAPPING(fio.sbi),
>>> + fio.old_blkaddr, fio.old_blkaddr);
>>> +
>>> set_page_dirty(fio.encrypted_page);
>>> if (clear_page_dirty_for_io(fio.encrypted_page))
>>> dec_page_count(fio.sbi, F2FS_DIRTY_META);
>>> @@ -871,11 +868,12 @@ static int move_data_block(struct inode *inode,
>>> block_t bidx,
>>> put_page_out:
>>> f2fs_put_page(fio.encrypted_page, 1);
>>> recover_block:
>>> - if (lfs_mode)
>>> - up_write(&fio.sbi->io_order_lock);
>>> if (err)
>>> f2fs_do_replace_block(fio.sbi, &sum, newaddr, fio.old_blkaddr,
>>> true, true);
>>> +up_out:
>>> + if (lfs_mode)
>>> + up_write(&fio.sbi->io_order_lock);
>>> put_out:
>>> f2fs_put_dnode(&dn);
>>> out:
>>>
>>
>>
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>> Linux-f2fs-devel@lists.sourceforge.net
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> .
>
