diff options
Diffstat (limited to 'io_uring/kbuf.c')
| -rw-r--r-- | io_uring/kbuf.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index bc58890d932b..b9c7f6e87cc9 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -83,6 +83,39 @@ static int io_buffer_add_list(struct io_ring_ctx *ctx, return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL)); } +unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags) +{ + unsigned int cflags; + + /* + * We can add this buffer back to two lists: + * + * 1) The io_buffers_cache list. This one is protected by the + * ctx->uring_lock. If we already hold this lock, add back to this + * list as we can grab it from issue as well. + * 2) The io_buffers_comp list. This one is protected by the + * ctx->completion_lock. + * + * We migrate buffers from the comp_list to the issue cache list + * when we need one. + */ + if (req->flags & REQ_F_BUFFER_RING) { + /* no buffers to recycle for this case */ + cflags = __io_put_kbuf_list(req, NULL); + } else if (issue_flags & IO_URING_F_UNLOCKED) { + struct io_ring_ctx *ctx = req->ctx; + + spin_lock(&ctx->completion_lock); + cflags = __io_put_kbuf_list(req, &ctx->io_buffers_comp); + spin_unlock(&ctx->completion_lock); + } else { + lockdep_assert_held(&req->ctx->uring_lock); + + cflags = __io_put_kbuf_list(req, &req->ctx->io_buffers_cache); + } + return cflags; +} + static void __user *io_provided_buffer_select(struct io_kiocb *req, size_t *len, struct io_buffer_list *bl) { |