diff options
| -rw-r--r-- | fs/io_uring.c | 138 | ||||
| -rw-r--r-- | include/uapi/linux/io_uring.h | 10 |
2 files changed, 145 insertions, 3 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 1f3ae208f6a6..1a58f2042815 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -447,6 +447,15 @@ struct io_splice { unsigned int flags; }; +struct io_provide_buf { + struct file *file; + __u64 addr; + __s32 len; + __u32 bgid; + __u16 nbufs; + __u16 bid; +}; + struct io_async_connect { struct sockaddr_storage address; }; @@ -572,6 +581,7 @@ struct io_kiocb { struct io_madvise madvise; struct io_epoll epoll; struct io_splice splice; + struct io_provide_buf pbuf; }; struct io_async_ctx *io; @@ -799,7 +809,8 @@ static const struct io_op_def io_op_defs[] = { .needs_file = 1, .hash_reg_file = 1, .unbound_nonreg_file = 1, - } + }, + [IORING_OP_PROVIDE_BUFFERS] = {}, }; static void io_wq_submit_work(struct io_wq_work **workptr); @@ -2785,6 +2796,120 @@ static int io_openat(struct io_kiocb *req, bool force_nonblock) return io_openat2(req, force_nonblock); } +static int io_provide_buffers_prep(struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ + struct io_provide_buf *p = &req->pbuf; + u64 tmp; + + if (sqe->ioprio || sqe->rw_flags) + return -EINVAL; + + tmp = READ_ONCE(sqe->fd); + if (!tmp || tmp > USHRT_MAX) + return -E2BIG; + p->nbufs = tmp; + p->addr = READ_ONCE(sqe->addr); + p->len = READ_ONCE(sqe->len); + + if (!access_ok(u64_to_user_ptr(p->addr), p->len)) + return -EFAULT; + + p->bgid = READ_ONCE(sqe->buf_group); + tmp = READ_ONCE(sqe->off); + if (tmp > USHRT_MAX) + return -E2BIG; + p->bid = tmp; + return 0; +} + +static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head) +{ + struct io_buffer *buf; + u64 addr = pbuf->addr; + int i, bid = pbuf->bid; + + for (i = 0; i < pbuf->nbufs; i++) { + buf = kmalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + break; + + buf->addr = addr; + buf->len = pbuf->len; + buf->bid = bid; + addr += pbuf->len; + bid++; + if (!*head) { + INIT_LIST_HEAD(&buf->list); + *head = buf; + } else { + list_add_tail(&buf->list, &(*head)->list); + } + } + + return i ? i : -ENOMEM; +} + +static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock) +{ + if (needs_lock) + mutex_unlock(&ctx->uring_lock); +} + +static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock) +{ + /* + * "Normal" inline submissions always hold the uring_lock, since we + * grab it from the system call. Same is true for the SQPOLL offload. + * The only exception is when we've detached the request and issue it + * from an async worker thread, grab the lock for that case. + */ + if (needs_lock) + mutex_lock(&ctx->uring_lock); +} + +static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock) +{ + struct io_provide_buf *p = &req->pbuf; + struct io_ring_ctx *ctx = req->ctx; + struct io_buffer *head, *list; + int ret = 0; + + io_ring_submit_lock(ctx, !force_nonblock); + + lockdep_assert_held(&ctx->uring_lock); + + list = head = idr_find(&ctx->io_buffer_idr, p->bgid); + + ret = io_add_buffers(p, &head); + if (ret < 0) + goto out; + + if (!list) { + ret = idr_alloc(&ctx->io_buffer_idr, head, p->bgid, p->bgid + 1, + GFP_KERNEL); + if (ret < 0) { + while (!list_empty(&head->list)) { + struct io_buffer *buf; + + buf = list_first_entry(&head->list, + struct io_buffer, list); + list_del(&buf->list); + kfree(buf); + } + kfree(head); + goto out; + } + } +out: + io_ring_submit_unlock(ctx, !force_nonblock); + if (ret < 0) + req_set_fail_links(req); + io_cqring_add_event(req, ret); + io_put_req(req); + return 0; +} + static int io_epoll_ctl_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { @@ -4392,6 +4517,9 @@ static int io_req_defer_prep(struct io_kiocb *req, case IORING_OP_SPLICE: ret = io_splice_prep(req, sqe); break; + case IORING_OP_PROVIDE_BUFFERS: + ret = io_provide_buffers_prep(req, sqe); + break; default: printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", req->opcode); @@ -4669,6 +4797,14 @@ static int io_issue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, } ret = io_splice(req, force_nonblock); break; + case IORING_OP_PROVIDE_BUFFERS: + if (sqe) { + ret = io_provide_buffers_prep(req, sqe); + if (ret) + break; + } + ret = io_provide_buffers(req, force_nonblock); + break; default: ret = -EINVAL; break; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 53b36311cdac..bc34a57a660b 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -45,8 +45,13 @@ struct io_uring_sqe { __u64 user_data; /* data to be passed back at completion time */ union { struct { - /* index into fixed buffers, if used */ - __u16 buf_index; + /* pack this to avoid bogus arm OABI complaints */ + union { + /* index into fixed buffers, if used */ + __u16 buf_index; + /* for grouped buffer selection */ + __u16 buf_group; + } __attribute__((packed)); /* personality to use, if used */ __u16 personality; __s32 splice_fd_in; @@ -119,6 +124,7 @@ enum { IORING_OP_OPENAT2, IORING_OP_EPOLL_CTL, IORING_OP_SPLICE, + IORING_OP_PROVIDE_BUFFERS, /* this goes last, obviously */ IORING_OP_LAST, |