Fix netfs_read_gaps() to remove the netfs_folio record from the folio record before marking the folio uptodate if it successfully fills the gaps around the dirty data in a streaming write folio (dirty, but not uptodate). Found with: fsx -q -N 1000000 -p 10000 -o 128000 -l 600000 \ /xfstest.test/junk --replay-ops=junk.fsxops using the following as junk.fsxops: truncate 0x0 0x138b1 0x8b15d * write 0x507ee 0x10df7 0x927c0 write 0x19993 0x10e04 0x927c0 * mapwrite 0x66214 0x1a253 0x927c0 copy_range 0xb704 0x89b9 0x24429 0x79380 write 0x2402b 0x144a2 0x90660 * mapwrite 0x204d5 0x140a0 0x927c0 * copy_range 0x1f72c 0x137d0 0x7a906 0x927c0 * read 0 0x9157c 0x9157c on cifs with the default cache option. It shows folio 0x24 misbehaving if the FMODE_READ check is commented out in netfs_perform_write(): if (//(file->f_mode & FMODE_READ) || netfs_is_cache_enabled(ctx)) { and no fscache. This was initially found with the generic/522 xfstest. Signed-off-by: David Howells cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Fixes: ee4cdf7ba857 ("netfs: Speed up buffered reading") --- fs/netfs/buffered_read.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/netfs/buffered_read.c b/fs/netfs/buffered_read.c index ebd84a6cc3f0..51f844bfbdff 100644 --- a/fs/netfs/buffered_read.c +++ b/fs/netfs/buffered_read.c @@ -395,6 +395,7 @@ static int netfs_read_gaps(struct file *file, struct folio *folio) { struct netfs_io_request *rreq; struct address_space *mapping = folio->mapping; + struct netfs_group *group = netfs_folio_group(folio); struct netfs_folio *finfo = netfs_folio_info(folio); struct netfs_inode *ctx = netfs_inode(mapping->host); struct folio *sink = NULL; @@ -461,6 +462,12 @@ static int netfs_read_gaps(struct file *file, struct folio *folio) ret = netfs_wait_for_read(rreq); if (ret >= 0) { + if (group) + folio_change_private(folio, group); + else + folio_detach_private(folio); + kfree(finfo); + trace_netfs_folio(folio, netfs_folio_trace_filled_gaps); flush_dcache_folio(folio); folio_mark_uptodate(folio); } @@ -496,10 +503,8 @@ int netfs_read_folio(struct file *file, struct folio *folio) struct netfs_inode *ctx = netfs_inode(mapping->host); int ret; - if (folio_test_dirty(folio)) { - trace_netfs_folio(folio, netfs_folio_trace_read_gaps); + if (folio_test_dirty(folio)) return netfs_read_gaps(file, folio); - } _enter("%lx", folio->index);