On 1/5/2026 11:31 PM, Nanzhe Zhao wrote:
f2fs_read_data_large_folio() can build a single read BIO across multiple
folios during readahead. If a folio ends up having none of its subpages
added to the BIO (e.g. all subpages are zeroed / treated as holes), it
will never be seen by f2fs_finish_read_bio(), so folio_end_read() is
never called. This leaves the folio locked and not marked uptodate.
Track whether the current folio has been added to a BIO via a local
'folio_in_bio' bool flag, and when iterating readahead folios, explicitly
mark the folio uptodate (on success) and unlock it when nothing was added.
Signed-off-by: Nanzhe Zhao <[email protected]>
---
fs/f2fs/data.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 66ab7a43a56f..ac569a396914 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2430,6 +2430,7 @@ static int f2fs_read_data_large_folio(struct inode *inode,
unsigned nrpages;
struct f2fs_folio_state *ffs;
int ret = 0;
+ bool folio_in_bio = false;
No need to initialize folio_in_bio?
if (!IS_IMMUTABLE(inode))
return -EOPNOTSUPP;
@@ -2445,6 +2446,7 @@ static int f2fs_read_data_large_folio(struct inode *inode,
if (!folio)
goto out;
+ folio_in_bio = false
folio_in_bio = false;
index = folio->index;
offset = 0;
ffs = NULL;
@@ -2530,6 +2532,7 @@ static int f2fs_read_data_large_folio(struct inode *inode,
offset << PAGE_SHIFT))
goto submit_and_realloc;
+ folio_in_bio = true;
inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA);
f2fs_update_iostat(F2FS_I_SB(inode), NULL, FS_DATA_READ_IO,
F2FS_BLKSIZE);
@@ -2539,6 +2542,11 @@ static int f2fs_read_data_large_folio(struct inode
*inode,
}
trace_f2fs_read_folio(folio, DATA);
if (rac) {
+ if (!folio_in_bio) {
+ if (!ret)
+ folio_mark_uptodate(folio);
+ folio_unlock(folio);
+ }
err_out:
/* Nothing was submitted. */
if (!bio) {
if (!ret)
folio_mark_uptodate(folio);
folio_unlock(folio);
^^^^^^^^^^^^
If all folios in rac have not been mapped (hole case), will we unlock the folio
twice?
Thanks,
return ret;
}
folio = readahead_folio(rac);
goto next_folio;
}
--
2.34.1
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