| Message ID | 20201009124954.31830-1-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] io_uring: Fix use of XArray in __io_uring_files_cancel | expand |
On 09/10/2020 15:49, Matthew Wilcox (Oracle) wrote: > We have to drop the lock during each iteration, so there's no advantage > to using the advanced API. Convert this to a standard xa_for_each() loop. LGTM, but would be better to add Reported-by: syzbot+27c12725d8ff0bfe1a13@syzkaller.appspotmail.com > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > --- > fs/io_uring.c | 19 +++++-------------- > 1 file changed, 5 insertions(+), 14 deletions(-) > > diff --git a/fs/io_uring.c b/fs/io_uring.c > index 299c530c66f9..2978cc78538a 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -8665,28 +8665,19 @@ static void io_uring_attempt_task_drop(struct file *file, bool exiting) > void __io_uring_files_cancel(struct files_struct *files) > { > struct io_uring_task *tctx = current->io_uring; > - XA_STATE(xas, &tctx->xa, 0); > + struct file *file; > + unsigned long index; > > /* make sure overflow events are dropped */ > tctx->in_idle = true; > > - do { > - struct io_ring_ctx *ctx; > - struct file *file; > - > - xas_lock(&xas); > - file = xas_next_entry(&xas, ULONG_MAX); > - xas_unlock(&xas); > - > - if (!file) > - break; > - > - ctx = file->private_data; > + xa_for_each(&tctx->xa, index, file) { > + struct io_ring_ctx *ctx = file->private_data; > > io_uring_cancel_task_requests(ctx, files); > if (files) > io_uring_del_task_file(file); > - } while (1); > + } > } > > static inline bool io_uring_task_idle(struct io_uring_task *tctx) >
diff --git a/fs/io_uring.c b/fs/io_uring.c index 299c530c66f9..2978cc78538a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -8665,28 +8665,19 @@ static void io_uring_attempt_task_drop(struct file *file, bool exiting) void __io_uring_files_cancel(struct files_struct *files) { struct io_uring_task *tctx = current->io_uring; - XA_STATE(xas, &tctx->xa, 0); + struct file *file; + unsigned long index; /* make sure overflow events are dropped */ tctx->in_idle = true; - do { - struct io_ring_ctx *ctx; - struct file *file; - - xas_lock(&xas); - file = xas_next_entry(&xas, ULONG_MAX); - xas_unlock(&xas); - - if (!file) - break; - - ctx = file->private_data; + xa_for_each(&tctx->xa, index, file) { + struct io_ring_ctx *ctx = file->private_data; io_uring_cancel_task_requests(ctx, files); if (files) io_uring_del_task_file(file); - } while (1); + } } static inline bool io_uring_task_idle(struct io_uring_task *tctx)
We have to drop the lock during each iteration, so there's no advantage to using the advanced API. Convert this to a standard xa_for_each() loop. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- fs/io_uring.c | 19 +++++-------------- 1 file changed, 5 insertions(+), 14 deletions(-)