Re: [PATCH v2 5/5] f2fs: fix to propagate error from __get_meta_page()

From: Chao Yu
Date: Sat Jul 14 2018 - 22:22:16 EST

On 2018/7/15 9:57, Jaegeuk Kim wrote:
> On 07/10, Chao Yu wrote:
>> From: Chao Yu <yuchao0@xxxxxxxxxx>
>>
>> If caller of __get_meta_page() can handle error, let's propagate error
>> from __get_meta_page().
>>
>> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
>> ---
>> v2:
>> - handle error path in __get_meta_page() correctly.
>> fs/f2fs/checkpoint.c | 21 +++++++++++++++++----
>> fs/f2fs/f2fs.h | 2 +-
>> fs/f2fs/node.c | 27 +++++++++++++++++++--------
>> fs/f2fs/recovery.c | 8 ++++++++
>> fs/f2fs/segment.c | 33 +++++++++++++++++++++++++++------
>> 5 files changed, 72 insertions(+), 19 deletions(-)
>>
>> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
>> index 41e6e5769a2c..b672fc1cdb05 100644
>> --- a/fs/f2fs/checkpoint.c
>> +++ b/fs/f2fs/checkpoint.c
>> @@ -71,6 +71,7 @@ static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
>> .encrypted_page = NULL,
>> .is_meta = is_meta,
>> };
>> + int err;
>>
>> if (unlikely(!is_meta))
>> fio.op_flags &= ~REQ_META;
>> @@ -85,11 +86,12 @@ static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
>>
>> fio.page = page;
>>
>> - if (f2fs_submit_page_bio(&fio)) {
>> + err = f2fs_submit_page_bio(&fio);
>> + if (err) {
>> memset(page_address(page), 0, PAGE_SIZE);
>
> No reason to do memset(), if we handle an error?

Agreed.

>
>> + f2fs_put_page(page, 1);
>> f2fs_stop_checkpoint(sbi, false);
>> - f2fs_bug_on(sbi, 1);
>
> Keep to f2fs_bug_on(1)?

If we want to report error return value to caller, we should not let system
panic here?

>
>> - return page;
>> + return ERR_PTR(err);
>> }
>>
>> lock_page(page);
>
> Need to return an error if read_end_io is failed below in the path.

Agreed, previously, I found that if we propagate the error to get_node_info(),
it will be a little hard to handle, anyway, let me try.

>
>> @@ -658,9 +660,15 @@ int f2fs_recover_orphan_inodes(struct f2fs_sb_info *sbi)
>> f2fs_ra_meta_pages(sbi, start_blk, orphan_blocks, META_CP, true);
>>
>> for (i = 0; i < orphan_blocks; i++) {
>> - struct page *page = f2fs_get_meta_page(sbi, start_blk + i);
>> + struct page *page;
>> struct f2fs_orphan_block *orphan_blk;
>>
>> + page = f2fs_get_meta_page(sbi, start_blk + i);
>> + if (IS_ERR(page)) {
>> + err = PTR_ERR(page);
>> + goto out;
>> + }
>> +
>> orphan_blk = (struct f2fs_orphan_block *)page_address(page);
>> for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
>> nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
>> @@ -751,6 +759,9 @@ static int get_checkpoint_version(struct f2fs_sb_info *sbi, block_t cp_addr,
>> __u32 crc = 0;
>>
>> *cp_page = f2fs_get_meta_page(sbi, cp_addr);
>> + if (IS_ERR(*cp_page))
>> + return PTR_ERR(*cp_page);
>> +
>> *cp_block = (struct f2fs_checkpoint *)page_address(*cp_page);
>>
>> crc_offset = le32_to_cpu((*cp_block)->checksum_offset);
>> @@ -876,6 +887,8 @@ int f2fs_get_valid_checkpoint(struct f2fs_sb_info *sbi)
>> unsigned char *ckpt = (unsigned char *)sbi->ckpt;
>>
>> cur_page = f2fs_get_meta_page(sbi, cp_blk_no + i);
>> + if (IS_ERR(cur_page))
>> + goto free_fail_no_cp;
>> sit_bitmap_ptr = page_address(cur_page);
>> memcpy(ckpt + i * blk_size, sit_bitmap_ptr, blk_size);
>> f2fs_put_page(cur_page, 1);
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index 359526d88d3f..76b51a0de3cd 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -2864,7 +2864,7 @@ int f2fs_try_to_free_nids(struct f2fs_sb_info *sbi, int nr_shrink);
>> void f2fs_recover_inline_xattr(struct inode *inode, struct page *page);
>> int f2fs_recover_xattr_data(struct inode *inode, struct page *page);
>> int f2fs_recover_inode_page(struct f2fs_sb_info *sbi, struct page *page);
>> -void f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
>> +int f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
>> unsigned int segno, struct f2fs_summary_block *sum);
>> void f2fs_flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc);
>> int f2fs_build_node_manager(struct f2fs_sb_info *sbi);
>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>> index c48e2a2e5e82..248d401bf40a 100644
>> --- a/fs/f2fs/node.c
>> +++ b/fs/f2fs/node.c
>> @@ -113,25 +113,26 @@ static void clear_node_page_dirty(struct page *page)
>>
>> static struct page *get_current_nat_page(struct f2fs_sb_info *sbi, nid_t nid)
>> {
>> - pgoff_t index = current_nat_addr(sbi, nid);
>> - return f2fs_get_meta_page(sbi, index);
>> + struct page *page;
>> +
>> + page = f2fs_get_meta_page(sbi, current_nat_addr(sbi, nid));
>> + BUG_ON(IS_ERR(page));
>
> Do we need this at this moment?

How can we handle this condition if there occurs read failure in
__get_meta_page()? just retrying f2fs_get_meta_page()?

>
>> + return page;
>> }
>>
>> static struct page *get_next_nat_page(struct f2fs_sb_info *sbi, nid_t nid)
>> {
>> struct page *src_page;
>> struct page *dst_page;
>> - pgoff_t src_off;
>> pgoff_t dst_off;
>> void *src_addr;
>> void *dst_addr;
>> struct f2fs_nm_info *nm_i = NM_I(sbi);
>>
>> - src_off = current_nat_addr(sbi, nid);
>> - dst_off = next_nat_addr(sbi, src_off);
>> + dst_off = next_nat_addr(sbi, current_nat_addr(sbi, nid));
>>
>> /* get current nat block page with lock */
>> - src_page = f2fs_get_meta_page(sbi, src_off);
>> + src_page = get_current_nat_page(sbi, nid);
>
> This is a different clean-up change.

Yes, let me split this into another cleanup patch.

Thanks,

>
>> dst_page = f2fs_grab_meta_page(sbi, dst_off);
>> f2fs_bug_on(sbi, PageDirty(src_page));
>>
>> @@ -2502,7 +2503,7 @@ int f2fs_recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
>> return 0;
>> }
>>
>> -void f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
>> +int f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
>> unsigned int segno, struct f2fs_summary_block *sum)
>> {
>> struct f2fs_node *rn;
>> @@ -2524,6 +2525,9 @@ void f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
>> for (idx = addr; idx < addr + nrpages; idx++) {
>> struct page *page = f2fs_get_tmp_page(sbi, idx);
>>
>> + if (IS_ERR(page))
>> + return PTR_ERR(page);
>> +
>> rn = F2FS_NODE(page);
>> sum_entry->nid = rn->footer.nid;
>> sum_entry->version = 0;
>> @@ -2535,6 +2539,7 @@ void f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
>> invalidate_mapping_pages(META_MAPPING(sbi), addr,
>> addr + nrpages);
>> }
>> + return 0;
>> }
>>
>> static void remove_nats_in_journal(struct f2fs_sb_info *sbi)
>> @@ -2771,7 +2776,13 @@ static int __get_nat_bitmaps(struct f2fs_sb_info *sbi)
>> nat_bits_addr = __start_cp_addr(sbi) + sbi->blocks_per_seg -
>> nm_i->nat_bits_blocks;
>> for (i = 0; i < nm_i->nat_bits_blocks; i++) {
>> - struct page *page = f2fs_get_meta_page(sbi, nat_bits_addr++);
>> + struct page *page;
>> +
>> + page = f2fs_get_meta_page(sbi, nat_bits_addr++);
>> + if (IS_ERR(page)) {
>> + disable_nat_bits(sbi, true);
>> + return PTR_ERR(page);
>> + }
>>
>> memcpy(nm_i->nat_bits + (i << F2FS_BLKSIZE_BITS),
>> page_address(page), F2FS_BLKSIZE);
>> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
>> index 0d927ae26c48..ac70d5547a97 100644
>> --- a/fs/f2fs/recovery.c
>> +++ b/fs/f2fs/recovery.c
>> @@ -256,6 +256,10 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,
>> return 0;
>>
>> page = f2fs_get_tmp_page(sbi, blkaddr);
>> + if (IS_ERR(page)) {
>> + err = PTR_ERR(page);
>> + break;
>> + }
>>
>> if (!is_recoverable_dnode(page))
>> break;
>> @@ -574,6 +578,10 @@ static int recover_data(struct f2fs_sb_info *sbi, struct list_head *inode_list,
>> f2fs_ra_meta_pages_cond(sbi, blkaddr);
>>
>> page = f2fs_get_tmp_page(sbi, blkaddr);
>> + if (IS_ERR(page)) {
>> + err = PTR_ERR(page);
>> + break;
>> + }
>>
>> if (!is_recoverable_dnode(page)) {
>> f2fs_put_page(page, 1);
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index e55188975fcc..22600002c690 100644
>> --- a/fs/f2fs/segment.c
>> +++ b/fs/f2fs/segment.c
>> @@ -2096,7 +2096,11 @@ int f2fs_npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
>> */
>> struct page *f2fs_get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
>> {
>> - return f2fs_get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
>> + struct page *page;
>> +
>> + page = f2fs_get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
>> + BUG_ON(IS_ERR(page));
>
> Ditto.
>
>> + return page;
>> }
>>
>> void f2fs_update_meta_page(struct f2fs_sb_info *sbi,
>> @@ -3122,7 +3126,7 @@ void f2fs_wait_on_block_writeback(struct f2fs_sb_info *sbi, block_t blkaddr)
>> }
>> }
>>
>> -static void read_compacted_summaries(struct f2fs_sb_info *sbi)
>> +static int read_compacted_summaries(struct f2fs_sb_info *sbi)
>> {
>> struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
>> struct curseg_info *seg_i;
>> @@ -3134,6 +3138,8 @@ static void read_compacted_summaries(struct f2fs_sb_info *sbi)
>> start = start_sum_block(sbi);
>>
>> page = f2fs_get_meta_page(sbi, start++);
>> + if (IS_ERR(page))
>> + return PTR_ERR(page);
>> kaddr = (unsigned char *)page_address(page);
>>
>> /* Step 1: restore nat cache */
>> @@ -3174,11 +3180,14 @@ static void read_compacted_summaries(struct f2fs_sb_info *sbi)
>> page = NULL;
>>
>> page = f2fs_get_meta_page(sbi, start++);
>> + if (IS_ERR(page))
>> + return PTR_ERR(page);
>> kaddr = (unsigned char *)page_address(page);
>> offset = 0;
>> }
>> }
>> f2fs_put_page(page, 1);
>> + return 0;
>> }
>>
>> static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>> @@ -3190,6 +3199,7 @@ static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>> unsigned short blk_off;
>> unsigned int segno = 0;
>> block_t blk_addr = 0;
>> + int err = 0;
>>
>> /* get segment number and block addr */
>> if (IS_DATASEG(type)) {
>> @@ -3213,6 +3223,8 @@ static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>> }
>>
>> new = f2fs_get_meta_page(sbi, blk_addr);
>> + if (IS_ERR(new))
>> + return PTR_ERR(new);
>> sum = (struct f2fs_summary_block *)page_address(new);
>>
>> if (IS_NODESEG(type)) {
>> @@ -3224,7 +3236,9 @@ static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>> ns->ofs_in_node = 0;
>> }
>> } else {
>> - f2fs_restore_node_summary(sbi, segno, sum);
>> + err = f2fs_restore_node_summary(sbi, segno, sum);
>> + if (err)
>> + goto out;
>> }
>> }
>>
>> @@ -3244,8 +3258,9 @@ static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
>> curseg->alloc_type = ckpt->alloc_type[type];
>> curseg->next_blkoff = blk_off;
>> mutex_unlock(&curseg->curseg_mutex);
>> +out:
>> f2fs_put_page(new, 1);
>> - return 0;
>> + return err;
>> }
>>
>> static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
>> @@ -3263,7 +3278,9 @@ static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
>> META_CP, true);
>>
>> /* restore for compacted data summary */
>> - read_compacted_summaries(sbi);
>> + err = read_compacted_summaries(sbi);
>> + if (err)
>> + return err;
>> type = CURSEG_HOT_NODE;
>> }
>>
>> @@ -3394,7 +3411,11 @@ int f2fs_lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
>> static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
>> unsigned int segno)
>> {
>> - return f2fs_get_meta_page(sbi, current_sit_addr(sbi, segno));
>> + struct page *page;
>> +
>> + page = f2fs_get_meta_page(sbi, current_sit_addr(sbi, segno));
>> + BUG_ON(IS_ERR(page));
>
> Ditoo.
>
>> + return page;
>> }
>>
>> static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
>> --
>> 2.16.2.17.g38e79b1fd