On Wed, Sep 07, 2022 at 02:51:31PM +0000, Chaitanya Kulkarni wrote: > >> req = nvme_alloc_user_request(q, cmd, ubuffer, bufflen, meta_buffer, >> - meta_len, meta_seed, &meta, timeout, vec, 0, 0); >> + meta_len, meta_seed, &meta, timeout, vec, 0, 0, NULL, 0); >> if (IS_ERR(req)) >> return PTR_ERR(req); > >14 Arguments to the function! > >Kanchan, I'm not pointing out to this patch it has happened over >the years, I think it is high time we find a way to trim this >down. > >Least we can do is to pass a structure member than 14 different >arguments, is everyone okay with it ? > Maybe it's just me, but there is something (unrelatedness) about these fields which makes packing all these into a single container feel bit unnatural (or do you already have a good name for such struct?). So how about we split the nvme_alloc_user_request into two. That will also serve the purpose. Here is a patch that creates - new nvme_alloc_user_request with 5 parameters - new nvme_map_user_request with 8 parameters diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c index 548aca8b5b9f..cb2fa4db50dd 100644 --- a/drivers/nvme/host/ioctl.c +++ b/drivers/nvme/host/ioctl.c @@ -65,18 +65,10 @@ static int nvme_finish_user_metadata(struct request *req, void __user *ubuf, } static struct request *nvme_alloc_user_request(struct request_queue *q, - struct nvme_command *cmd, void __user *ubuffer, - unsigned bufflen, void __user *meta_buffer, unsigned meta_len, - u32 meta_seed, void **metap, unsigned timeout, bool vec, + struct nvme_command *cmd, unsigned timeout, blk_opf_t rq_flags, blk_mq_req_flags_t blk_flags) { - bool write = nvme_is_write(cmd); - struct nvme_ns *ns = q->queuedata; - struct block_device *bdev = ns ? ns->disk->part0 : NULL; struct request *req; - struct bio *bio = NULL; - void *meta = NULL; - int ret; req = blk_mq_alloc_request(q, nvme_req_op(cmd) | rq_flags, blk_flags); if (IS_ERR(req)) @@ -86,49 +78,61 @@ static struct request *nvme_alloc_user_request(struct request_queue *q, if (timeout) req->timeout = timeout; nvme_req(req)->flags |= NVME_REQ_USERCMD; + return req; +} - if (ubuffer && bufflen) { - if (!vec) - ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen, - GFP_KERNEL); - else { - struct iovec fast_iov[UIO_FASTIOV]; - struct iovec *iov = fast_iov; - struct iov_iter iter; - - ret = import_iovec(rq_data_dir(req), ubuffer, bufflen, - UIO_FASTIOV, &iov, &iter); - if (ret < 0) - goto out; - ret = blk_rq_map_user_iov(q, req, NULL, &iter, - GFP_KERNEL); - kfree(iov); - } - if (ret) +static int nvme_map_user_request(struct request *req, void __user *ubuffer, + unsigned bufflen, void __user *meta_buffer, unsigned meta_len, + u32 meta_seed, void **metap, bool vec) +{ + struct request_queue *q = req->q; + struct nvme_ns *ns = q->queuedata; + struct block_device *bdev = ns ? ns->disk->part0 : NULL; + struct bio *bio = NULL; + void *meta = NULL; + int ret; + + if (!ubuffer || !bufflen) + return 0; + + if (!vec) + ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen, + GFP_KERNEL); + else { + struct iovec fast_iov[UIO_FASTIOV]; + struct iovec *iov = fast_iov; + struct iov_iter iter; + + ret = import_iovec(rq_data_dir(req), ubuffer, bufflen, + UIO_FASTIOV, &iov, &iter); + if (ret < 0) goto out; - bio = req->bio; - if (bdev) - bio_set_dev(bio, bdev); - if (bdev && meta_buffer && meta_len) { - meta = nvme_add_user_metadata(bio, meta_buffer, meta_len, - meta_seed, write); - if (IS_ERR(meta)) { - ret = PTR_ERR(meta); - goto out_unmap; - } - req->cmd_flags |= REQ_INTEGRITY; - *metap = meta; + ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL); + kfree(iov); + } + bio = req->bio; + if (ret) + goto out_unmap; + if (bdev) + bio_set_dev(bio, bdev); + if (bdev && meta_buffer && meta_len) { + meta = nvme_add_user_metadata(bio, meta_buffer, meta_len, + meta_seed, req_op(req) == REQ_OP_DRV_OUT); + if (IS_ERR(meta)) { + ret = PTR_ERR(meta); + goto out_unmap; } + req->cmd_flags |= REQ_INTEGRITY; + *metap = meta; } - return req; + return ret; out_unmap: if (bio) blk_rq_unmap_user(bio); out: - blk_mq_free_request(req); - return ERR_PTR(ret); + return ret; } static int nvme_submit_user_cmd(struct request_queue *q, @@ -141,13 +145,16 @@ static int nvme_submit_user_cmd(struct request_queue *q, struct bio *bio; int ret; - req = nvme_alloc_user_request(q, cmd, ubuffer, bufflen, meta_buffer, - meta_len, meta_seed, &meta, timeout, vec, 0, 0); + req = nvme_alloc_user_request(q, cmd, timeout, 0, 0); if (IS_ERR(req)) return PTR_ERR(req); - bio = req->bio; + ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer, + meta_len, meta_seed, &meta, vec); + if (ret) + goto out; + bio = req->bio; ret = nvme_execute_passthru_rq(req); if (result) @@ -157,6 +164,7 @@ static int nvme_submit_user_cmd(struct request_queue *q, meta_len, ret); if (bio) blk_rq_unmap_user(bio); +out: blk_mq_free_request(req); return ret; } @@ -418,6 +426,7 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns, blk_opf_t rq_flags = 0; blk_mq_req_flags_t blk_flags = 0; void *meta = NULL; + int ret; if (!capable(CAP_SYS_ADMIN)) return -EACCES; @@ -457,13 +466,17 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns, rq_flags |= REQ_POLLED; retry: - req = nvme_alloc_user_request(q, &c, nvme_to_user_ptr(d.addr), - d.data_len, nvme_to_user_ptr(d.metadata), - d.metadata_len, 0, &meta, d.timeout_ms ? - msecs_to_jiffies(d.timeout_ms) : 0, vec, rq_flags, - blk_flags); + req = nvme_alloc_user_request(q, &c, + d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0, + rq_flags, blk_flags); if (IS_ERR(req)) return PTR_ERR(req); + + ret = nvme_map_user_request(req, nvme_to_user_ptr(d.addr), + d.data_len, nvme_to_user_ptr(d.metadata), + d.metadata_len, 0, &meta, vec); + if (ret) + goto out_err; req->end_io = nvme_uring_cmd_end_io; req->end_io_data = ioucmd; @@ -486,6 +499,9 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns, blk_execute_rq_nowait(req, false); return -EIOCBQUEUED; +out_err: + blk_mq_free_request(req); + return ret; } static bool is_ctrl_ioctl(unsigned int cmd)