diff options
| -rw-r--r-- | io_uring/kbuf.c | 71 | ||||
| -rw-r--r-- | io_uring/kbuf.h | 21 |
2 files changed, 49 insertions, 43 deletions
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index 62de0dda24bf..8bf47e49ea5b 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -37,36 +37,30 @@ static inline struct io_buffer_list *io_buffer_get_list(struct io_ring_ctx *ctx, return xa_load(&ctx->io_bl_xa, bgid); } -void __io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags) +static int io_buffer_add_list(struct io_ring_ctx *ctx, + struct io_buffer_list *bl, unsigned int bgid) +{ + bl->bgid = bgid; + if (bgid < BGID_ARRAY) + return 0; + + return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL)); +} + +void io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags) { struct io_ring_ctx *ctx = req->ctx; struct io_buffer_list *bl; struct io_buffer *buf; /* - * We don't need to recycle for REQ_F_BUFFER_RING, we can just clear - * the flag and hence ensure that bl->head doesn't get incremented. - * If the tail has already been incremented, hang on to it. + * For legacy provided buffer mode, don't recycle if we already did + * IO to this buffer. For ring-mapped provided buffer mode, we should + * increment ring->head to explicitly monopolize the buffer to avoid + * multiple use. */ - if (req->flags & REQ_F_BUFFER_RING) { - if (req->buf_list) { - if (req->flags & REQ_F_PARTIAL_IO) { - /* - * If we end up here, then the io_uring_lock has - * been kept held since we retrieved the buffer. - * For the io-wq case, we already cleared - * req->buf_list when the buffer was retrieved, - * hence it cannot be set here for that case. - */ - req->buf_list->head++; - req->buf_list = NULL; - } else { - req->buf_index = req->buf_list->bgid; - req->flags &= ~REQ_F_BUFFER_RING; - } - } + if (req->flags & REQ_F_PARTIAL_IO) return; - } io_ring_submit_lock(ctx, issue_flags); @@ -77,16 +71,35 @@ void __io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags) req->buf_index = buf->bgid; io_ring_submit_unlock(ctx, issue_flags); + return; } -static int io_buffer_add_list(struct io_ring_ctx *ctx, - struct io_buffer_list *bl, unsigned int bgid) +void io_kbuf_recycle_ring(struct io_kiocb *req) { - bl->bgid = bgid; - if (bgid < BGID_ARRAY) - return 0; - - return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL)); + /* + * We don't need to recycle for REQ_F_BUFFER_RING, we can just clear + * the flag and hence ensure that bl->head doesn't get incremented. + * If the tail has already been incremented, hang on to it. + * The exception is partial io, that case we should increment bl->head + * to monopolize the buffer. + */ + if (req->buf_list) { + if (req->flags & REQ_F_PARTIAL_IO) { + /* + * If we end up here, then the io_uring_lock has + * been kept held since we retrieved the buffer. + * For the io-wq case, we already cleared + * req->buf_list when the buffer was retrieved, + * hence it cannot be set here for that case. + */ + req->buf_list->head++; + req->buf_list = NULL; + } else { + req->buf_index = req->buf_list->bgid; + req->flags &= ~REQ_F_BUFFER_RING; + } + } + return; } unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags) diff --git a/io_uring/kbuf.h b/io_uring/kbuf.h index 304e7139d835..721465c5d809 100644 --- a/io_uring/kbuf.h +++ b/io_uring/kbuf.h @@ -35,7 +35,6 @@ struct io_buffer { void __user *io_buffer_select(struct io_kiocb *req, size_t *len, unsigned int issue_flags); -void __io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags); void io_destroy_buffers(struct io_ring_ctx *ctx); int io_remove_buffers_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); @@ -49,6 +48,9 @@ int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg); unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags); +void io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags); +void io_kbuf_recycle_ring(struct io_kiocb *req); + static inline bool io_do_buffer_select(struct io_kiocb *req) { if (!(req->flags & REQ_F_BUFFER_SELECT)) @@ -58,18 +60,6 @@ static inline bool io_do_buffer_select(struct io_kiocb *req) static inline void io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags) { - if (!(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING))) - return; - /* - * For legacy provided buffer mode, don't recycle if we already did - * IO to this buffer. For ring-mapped provided buffer mode, we should - * increment ring->head to explicitly monopolize the buffer to avoid - * multiple use. - */ - if ((req->flags & REQ_F_BUFFER_SELECTED) && - (req->flags & REQ_F_PARTIAL_IO)) - return; - /* * READV uses fields in `struct io_rw` (len/addr) to stash the selected * buffer data. However if that buffer is recycled the original request @@ -78,7 +68,10 @@ static inline void io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags) if (req->opcode == IORING_OP_READV) return; - __io_kbuf_recycle(req, issue_flags); + if (req->flags & REQ_F_BUFFER_SELECTED) + io_kbuf_recycle_legacy(req, issue_flags); + if (req->flags & REQ_F_BUFFER_RING) + io_kbuf_recycle_ring(req); } static inline unsigned int __io_put_kbuf_list(struct io_kiocb *req, |