[PATCH 5.10 02/54] io_uring: add a {task,files} pair matching helper

Greg Kroah-Hartman
2021-02-11T16:28:23Z

From: Pavel Begunkov <asml.silence@gmail.com>

[ Upstream commit 08d23634643c239ddae706758f54d3a8e0c24962 ]

Add io_match_task() that matches both task and files.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/io_uring.c | 63 +++++++++++++++++++++++++++++-----------------------------
1 file changed, 32 insertions(+), 31 deletions(-)

--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -997,6 +997,36 @@ static inline void io_clean_op(struct io
__io_clean_op(req);
}

+static inline bool __io_match_files(struct io_kiocb *req,
+ struct files_struct *files)
+{
+ return ((req->flags & REQ_F_WORK_INITIALIZED) &&
+ (req->work.flags & IO_WQ_WORK_FILES)) &&
+ req->work.identity->files == files;
+}
+
+static bool io_match_task(struct io_kiocb *head,
+ struct task_struct *task,
+ struct files_struct *files)
+{
+ struct io_kiocb *link;
+
+ if (task && head->task != task)
+ return false;
+ if (!files)
+ return true;
+ if (__io_match_files(head, files))
+ return true;
+ if (head->flags & REQ_F_LINK_HEAD) {
+ list_for_each_entry(link, &head->link_list, link_list) {
+ if (__io_match_files(link, files))
+ return true;
+ }
+ }
+ return false;
+}
+
+
static void io_sq_thread_drop_mm(void)
{
struct mm_struct *mm = current->mm;
@@ -1612,32 +1642,6 @@ static void io_cqring_mark_overflow(stru
}
}

-static inline bool __io_match_files(struct io_kiocb *req,
- struct files_struct *files)
-{
- return ((req->flags & REQ_F_WORK_INITIALIZED) &&
- (req->work.flags & IO_WQ_WORK_FILES)) &&
- req->work.identity->files == files;
-}
-
-static bool io_match_files(struct io_kiocb *req,
- struct files_struct *files)
-{
- struct io_kiocb *link;
-
- if (!files)
- return true;
- if (__io_match_files(req, files))
- return true;
- if (req->flags & REQ_F_LINK_HEAD) {
- list_for_each_entry(link, &req->link_list, link_list) {
- if (__io_match_files(link, files))
- return true;
- }
- }
- return false;
-}
-
/* Returns true if there are no backlogged entries after the flush */
static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
struct task_struct *tsk,
@@ -1659,9 +1663,7 @@ static bool __io_cqring_overflow_flush(s

cqe = NULL;
list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) {
- if (tsk && req->task != tsk)
- continue;
- if (!io_match_files(req, files))
+ if (!io_match_task(req, tsk, files))
continue;

cqe = io_get_cqring(ctx);
@@ -8635,8 +8637,7 @@ static void io_cancel_defer_files(struct

spin_lock_irq(&ctx->completion_lock);
list_for_each_entry_reverse(de, &ctx->defer_list, list) {
- if (io_task_match(de->req, task) &&
- io_match_files(de->req, files)) {
+ if (io_match_task(de->req, task, files)) {
list_cut_position(&list, &ctx->defer_list, &de->list);
break;
}