[for-next,v11,04/13] nvme: refactor nvme_alloc_request

Commit Message

Anuj Gupta Sept. 29, 2022, 12:06 p.m. UTC

From: Kanchan Joshi <[e-mail]>

nvme_alloc_request expects a large number of parameters.
Split this out into two functions to reduce number of parameters.
First one retains the name nvme_alloc_request, while second one is
named nvme_map_user_request.

Signed-off-by: Kanchan Joshi <[e-mail]>
Signed-off-by: Anuj Gupta <[e-mail]>
---
 drivers/nvme/host/ioctl.c | 120 ++++++++++++++++++++++----------------
 1 file changed, 69 insertions(+), 51 deletions(-)

Comments

Christoph Hellwig Sept. 29, 2022, 1:25 p.m. UTC | #1

On Thu, Sep 29, 2022 at 05:36:23PM +0530, Anuj Gupta wrote:
> From: Kanchan Joshi <[e-mail]>
> 
> nvme_alloc_request expects a large number of parameters.
> Split this out into two functions to reduce number of parameters.
> First one retains the name nvme_alloc_request, while second one is
> named nvme_map_user_request.

Looks good:

Reviewed-by: Christoph Hellwig <[e-mail]>

kernel test robot Sept. 29, 2022, 7:48 p.m. UTC | #2

Hi Anuj,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on axboe-block/for-next]
[also build test WARNING on next-20220929]
[cannot apply to mkp-scsi/for-next jejb-scsi/for-next linus/master v6.0-rc7]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Anuj-Gupta/io_uring-add-io_uring_cmd_import_fixed/20220929-210700
base:   https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next
config: arm-randconfig-r034-20220928
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 791a7ae1ba3efd6bca96338e10ffde557ba83920)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://github.com/intel-lab-lkp/linux/commit/9190651f70aa4ccfea762e702f762849ecefa7c5
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Anuj-Gupta/io_uring-add-io_uring_cmd_import_fixed/20220929-210700
        git checkout 9190651f70aa4ccfea762e702f762849ecefa7c5
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/nvme/host/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[e-mail]>

All warnings (new ones prefixed by >>):

>> drivers/nvme/host/ioctl.c:158:7: warning: variable 'effects' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
                   if (ret)
                       ^~~
   drivers/nvme/host/ioctl.c:177:6: note: uninitialized use occurs here
           if (effects)
               ^~~~~~~
   drivers/nvme/host/ioctl.c:158:3: note: remove the 'if' if its condition is always false
                   if (ret)
                   ^~~~~~~~
   drivers/nvme/host/ioctl.c:147:13: note: initialize the variable 'effects' to silence this warning
           u32 effects;
                      ^
                       = 0
   1 warning generated.


vim +158 drivers/nvme/host/ioctl.c

   137	
   138	static int nvme_submit_user_cmd(struct request_queue *q,
   139			struct nvme_command *cmd, void __user *ubuffer,
   140			unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
   141			u32 meta_seed, u64 *result, unsigned timeout, bool vec)
   142	{
   143		struct nvme_ctrl *ctrl;
   144		struct request *req;
   145		void *meta = NULL;
   146		struct bio *bio;
   147		u32 effects;
   148		int ret;
   149	
   150		req = nvme_alloc_user_request(q, cmd, 0, 0);
   151		if (IS_ERR(req))
   152			return PTR_ERR(req);
   153	
   154		req->timeout = timeout;
   155		if (ubuffer && bufflen) {
   156			ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
   157					meta_len, meta_seed, &meta, vec);
 > 158			if (ret)
   159				goto out;
   160		}
   161	
   162		bio = req->bio;
   163		ctrl = nvme_req(req)->ctrl;
   164	
   165		ret = nvme_execute_passthru_rq(req, &effects);
   166	
   167		if (result)
   168			*result = le64_to_cpu(nvme_req(req)->result.u64);
   169		if (meta)
   170			ret = nvme_finish_user_metadata(req, meta_buffer, meta,
   171							meta_len, ret);
   172		if (bio)
   173			blk_rq_unmap_user(bio);
   174	out:
   175		blk_mq_free_request(req);
   176	
   177		if (effects)
   178			nvme_passthru_end(ctrl, effects, cmd, ret);
   179	
   180		return ret;
   181	}
   182

Patch

diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 749f588a1228..0143f62b27c2 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -70,68 +70,69 @@  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,
-		blk_opf_t rq_flags, blk_mq_req_flags_t blk_flags)
+		struct nvme_command *cmd, blk_opf_t rq_flags,
+		blk_mq_req_flags_t blk_flags)
 {
-	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))
 		return req;
 	nvme_init_request(req, cmd);
-
-	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 (!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(req, meta_buffer,
-					meta_len, meta_seed);
-			if (IS_ERR(meta)) {
-				ret = PTR_ERR(meta);
-				goto out_unmap;
-			}
-			*metap = meta;
+
+		ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL);
+		kfree(iov);
+	}
+	if (ret)
+		goto out;
+	bio = req->bio;
+	if (bdev)
+		bio_set_dev(bio, bdev);
+
+	if (bdev && meta_buffer && meta_len) {
+		meta = nvme_add_user_metadata(req, meta_buffer, meta_len,
+				meta_seed);
+		if (IS_ERR(meta)) {
+			ret = PTR_ERR(meta);
+			goto out_unmap;
 		}
+		*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,
@@ -146,11 +147,18 @@  static int nvme_submit_user_cmd(struct request_queue *q,
 	u32 effects;
 	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, 0, 0);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
+	req->timeout = timeout;
+	if (ubuffer && bufflen) {
+		ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
+				meta_len, meta_seed, &meta, vec);
+		if (ret)
+			goto out;
+	}
+
 	bio = req->bio;
 	ctrl = nvme_req(req)->ctrl;
 
@@ -163,6 +171,7 @@  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);
 
 	if (effects)
@@ -470,6 +479,7 @@  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;
@@ -509,13 +519,18 @@  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, rq_flags, blk_flags);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
+	req->timeout = d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0;
+
+	if (d.addr && d.data_len) {
+		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;
+	}
 
 	if (issue_flags & IO_URING_F_IOPOLL && rq_flags & REQ_POLLED) {
 		if (unlikely(!req->bio)) {
@@ -541,6 +556,9 @@  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)