diff mbox series

[v2] scsi: ibmvscsi: Use dma_alloc_noncoherent() instead of get_zeroed_page/dma_map_single()

Message ID 20211012032317.2360-1-caihuoqing@baidu.com (mailing list archive)
State Changes Requested
Headers show
Series [v2] scsi: ibmvscsi: Use dma_alloc_noncoherent() instead of get_zeroed_page/dma_map_single() | expand

Commit Message

Cai,Huoqing Oct. 12, 2021, 3:23 a.m. UTC
Replacing get_zeroed_page/free_page/dma_map_single/dma_unmap_single()
with dma_alloc_noncoherent/dma_free_noncoherent() helps to reduce
code size, and simplify the code, and the hardware can keeep DMA
coherent itself.

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
---
v1->v2:
	*Change to dma_alloc/free_noncoherent from dma_alloc/free_coherent.
	*Update changelog.

 drivers/scsi/ibmvscsi/ibmvfc.c   | 16 ++++------------
 drivers/scsi/ibmvscsi/ibmvscsi.c | 29 +++++++++--------------------
 2 files changed, 13 insertions(+), 32 deletions(-)

Comments

Nathan Lynch Oct. 14, 2021, 7:25 p.m. UTC | #1
Cai Huoqing <caihuoqing@baidu.com> writes:
> @@ -331,18 +329,12 @@ static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
>  	int retrc;
>  	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
>  
> -	queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
> -
> -	if (!queue->msgs)
> -		goto malloc_failed;
>  	queue->size = PAGE_SIZE / sizeof(*queue->msgs);
> -
> -	queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
> -					  queue->size * sizeof(*queue->msgs),
> -					  DMA_BIDIRECTIONAL);
> -
> -	if (dma_mapping_error(hostdata->dev, queue->msg_token))
> -		goto map_failed;
> +	queue->msgs = dma_alloc_noncoherent(hostdata->dev,
> +					    PAGE_SIZE, &queue->msg_token,
> +					    DMA_BIDIRECTIONAL, GFP_KERNEL);
> +	if (!queue->msg)
> +		goto malloc_failed;


This version appears to retain the build breakage from v1 which was
reported here:

https://lore.kernel.org/linuxppc-dev/202110121452.nWPHZeZg-lkp@intel.com/

   drivers/scsi/ibmvscsi/ibmvscsi.c: In function 'ibmvscsi_init_crq_queue':
>> drivers/scsi/ibmvscsi/ibmvscsi.c:334:21: error: 'struct crq_queue' has no member named 'msg'; did you mean 'msgs'?
     334 |         if (!queue->msg)
         |                     ^~~
         |                     msgs
   drivers/scsi/ibmvscsi/ibmvscsi.c:388:60: error: 'struct crq_queue' has no member named 'msg'; did you mean 'msgs'?
     388 |         dma_free_coherent(hostdata->dev, PAGE_SIZE, queue->msg, queue->msg_token);
         |                                                            ^~~
         |                                                            msgs
Tyrel Datwyler Oct. 14, 2021, 10:07 p.m. UTC | #2
On 10/11/21 8:23 PM, Cai Huoqing wrote:
> Replacing get_zeroed_page/free_page/dma_map_single/dma_unmap_single()
> with dma_alloc_noncoherent/dma_free_noncoherent() helps to reduce
> code size, and simplify the code, and the hardware can keeep DMA
> coherent itsel
Not sure why the switch from coherent in v1 to noncoherent in v2. I think that
was unnecessary and I believe requires explicit synchronization via
dma_sync_single_{for_device|for_cpu} calls.

Further, as both kernel-bot and Nathan have already pointed out this doesn't
even compile.

-Tyrel

> 
> Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
> ---
> v1->v2:
> 	*Change to dma_alloc/free_noncoherent from dma_alloc/free_coherent.
> 	*Update changelog.
> 
>  drivers/scsi/ibmvscsi/ibmvfc.c   | 16 ++++------------
>  drivers/scsi/ibmvscsi/ibmvscsi.c | 29 +++++++++--------------------
>  2 files changed, 13 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
> index 1f1586ad48fe..6e95fd02fd25 100644
> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c
> @@ -869,8 +869,8 @@ static void ibmvfc_free_queue(struct ibmvfc_host *vhost,
>  {
>  	struct device *dev = vhost->dev;
>  
> -	dma_unmap_single(dev, queue->msg_token, PAGE_SIZE, DMA_BIDIRECTIONAL);
> -	free_page((unsigned long)queue->msgs.handle);
> +	dma_free_noncoherent(dev, PAGE_SIZE, queue->msgs.handle,
> +			     queue->msg_token, DMA_BIDIRECTIONAL);
>  	queue->msgs.handle = NULL;
>  
>  	ibmvfc_free_event_pool(vhost, queue);
> @@ -5663,19 +5663,11 @@ static int ibmvfc_alloc_queue(struct ibmvfc_host *vhost,
>  		return -ENOMEM;
>  	}
>  
> -	queue->msgs.handle = (void *)get_zeroed_page(GFP_KERNEL);
> +	queue->msgs.handle = dma_alloc_noncoherent(dev, PAGE_SIZE, &queue->msg_token,
> +						   DMA_BIDIRECTIONAL, GFP_KERNEL);
>  	if (!queue->msgs.handle)
>  		return -ENOMEM;
>  
> -	queue->msg_token = dma_map_single(dev, queue->msgs.handle, PAGE_SIZE,
> -					  DMA_BIDIRECTIONAL);
> -
> -	if (dma_mapping_error(dev, queue->msg_token)) {
> -		free_page((unsigned long)queue->msgs.handle);
> -		queue->msgs.handle = NULL;
> -		return -ENOMEM;
> -	}
> -
>  	queue->cur = 0;
>  	queue->fmt = fmt;
>  	queue->size = PAGE_SIZE / fmt_size;
> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
> index ea8e01f49cba..68409c298c74 100644
> --- a/drivers/scsi/ibmvscsi/ibmvscsi.c
> +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
> @@ -151,10 +151,8 @@ static void ibmvscsi_release_crq_queue(struct crq_queue *queue,
>  			msleep(100);
>  		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
>  	} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
> -	dma_unmap_single(hostdata->dev,
> -			 queue->msg_token,
> -			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
> -	free_page((unsigned long)queue->msgs);
> +	dma_free_noncoherent(hostdata->dev, PAGE_SIZE,
> +			     queue->msgs, queue->msg_token, DMA_BIDIRECTIONAL);
>  }
>  
>  /**
> @@ -331,18 +329,12 @@ static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
>  	int retrc;
>  	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
>  
> -	queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
> -
> -	if (!queue->msgs)
> -		goto malloc_failed;
>  	queue->size = PAGE_SIZE / sizeof(*queue->msgs);
> -
> -	queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
> -					  queue->size * sizeof(*queue->msgs),
> -					  DMA_BIDIRECTIONAL);
> -
> -	if (dma_mapping_error(hostdata->dev, queue->msg_token))
> -		goto map_failed;
> +	queue->msgs = dma_alloc_noncoherent(hostdata->dev,
> +					    PAGE_SIZE, &queue->msg_token,
> +					    DMA_BIDIRECTIONAL, GFP_KERNEL);
> +	if (!queue->msg)
> +		goto malloc_failed;
>  
>  	gather_partition_info();
>  	set_adapter_info(hostdata);
> @@ -395,11 +387,8 @@ static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
>  		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
>  	} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
>        reg_crq_failed:
> -	dma_unmap_single(hostdata->dev,
> -			 queue->msg_token,
> -			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
> -      map_failed:
> -	free_page((unsigned long)queue->msgs);
> +	dma_free_noncoherent(hostdata->dev, PAGE_SIZE, queue->msg,
> +			     queue->msg_token, DMA_BIDIRECTIONAL);
>        malloc_failed:
>  	return -1;
>  }
>
kernel test robot Nov. 8, 2021, 2:49 p.m. UTC | #3
Hi Cai,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on v5.15 next-20211108]
[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]

url:    https://github.com/0day-ci/linux/commits/Cai-Huoqing/scsi-ibmvscsi-Use-dma_alloc_noncoherent-instead-of-get_zeroed_page-dma_map_single/20211012-112447
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc64-defconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 11.2.0
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
        # https://github.com/0day-ci/linux/commit/ff4f34f9b1f3a0f14ed7472b8f4da0e12dc63d56
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Cai-Huoqing/scsi-ibmvscsi-Use-dma_alloc_noncoherent-instead-of-get_zeroed_page-dma_map_single/20211012-112447
        git checkout ff4f34f9b1f3a0f14ed7472b8f4da0e12dc63d56
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=powerpc SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/scsi/ibmvscsi/ibmvscsi.c: In function 'ibmvscsi_init_crq_queue':
>> drivers/scsi/ibmvscsi/ibmvscsi.c:336:21: error: 'struct crq_queue' has no member named 'msg'; did you mean 'msgs'?
     336 |         if (!queue->msg)
         |                     ^~~
         |                     msgs
   drivers/scsi/ibmvscsi/ibmvscsi.c:390:63: error: 'struct crq_queue' has no member named 'msg'; did you mean 'msgs'?
     390 |         dma_free_noncoherent(hostdata->dev, PAGE_SIZE, queue->msg,
         |                                                               ^~~
         |                                                               msgs


vim +336 drivers/scsi/ibmvscsi/ibmvscsi.c

   313	
   314	/**
   315	 * ibmvscsi_init_crq_queue() - Initializes and registers CRQ with hypervisor
   316	 * @queue:		crq_queue to initialize and register
   317	 * @hostdata:		ibmvscsi_host_data of host
   318	 * @max_requests:	maximum requests (unused)
   319	 *
   320	 * Allocates a page for messages, maps it for dma, and registers
   321	 * the crq with the hypervisor.
   322	 * Returns zero on success.
   323	 */
   324	static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
   325					   struct ibmvscsi_host_data *hostdata,
   326					   int max_requests)
   327	{
   328		int rc;
   329		int retrc;
   330		struct vio_dev *vdev = to_vio_dev(hostdata->dev);
   331	
   332		queue->size = PAGE_SIZE / sizeof(*queue->msgs);
   333		queue->msgs = dma_alloc_noncoherent(hostdata->dev,
   334						    PAGE_SIZE, &queue->msg_token,
   335						    DMA_BIDIRECTIONAL, GFP_KERNEL);
 > 336		if (!queue->msg)
   337			goto malloc_failed;
   338	
   339		gather_partition_info();
   340		set_adapter_info(hostdata);
   341	
   342		retrc = rc = plpar_hcall_norets(H_REG_CRQ,
   343					vdev->unit_address,
   344					queue->msg_token, PAGE_SIZE);
   345		if (rc == H_RESOURCE)
   346			/* maybe kexecing and resource is busy. try a reset */
   347			rc = ibmvscsi_reset_crq_queue(queue,
   348						      hostdata);
   349	
   350		if (rc == H_CLOSED) {
   351			/* Adapter is good, but other end is not ready */
   352			dev_warn(hostdata->dev, "Partner adapter not ready\n");
   353			retrc = 0;
   354		} else if (rc != 0) {
   355			dev_warn(hostdata->dev, "Error %d opening adapter\n", rc);
   356			goto reg_crq_failed;
   357		}
   358	
   359		queue->cur = 0;
   360		spin_lock_init(&queue->lock);
   361	
   362		tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
   363			     (unsigned long)hostdata);
   364	
   365		if (request_irq(vdev->irq,
   366				ibmvscsi_handle_event,
   367				0, "ibmvscsi", (void *)hostdata) != 0) {
   368			dev_err(hostdata->dev, "couldn't register irq 0x%x\n",
   369				vdev->irq);
   370			goto req_irq_failed;
   371		}
   372	
   373		rc = vio_enable_interrupts(vdev);
   374		if (rc != 0) {
   375			dev_err(hostdata->dev, "Error %d enabling interrupts!!!\n", rc);
   376			goto req_irq_failed;
   377		}
   378	
   379		return retrc;
   380	
   381	      req_irq_failed:
   382		tasklet_kill(&hostdata->srp_task);
   383		rc = 0;
   384		do {
   385			if (rc)
   386				msleep(100);
   387			rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
   388		} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
   389	      reg_crq_failed:
   390		dma_free_noncoherent(hostdata->dev, PAGE_SIZE, queue->msg,
   391				     queue->msg_token, DMA_BIDIRECTIONAL);
   392	      malloc_failed:
   393		return -1;
   394	}
   395	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 1f1586ad48fe..6e95fd02fd25 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -869,8 +869,8 @@  static void ibmvfc_free_queue(struct ibmvfc_host *vhost,
 {
 	struct device *dev = vhost->dev;
 
-	dma_unmap_single(dev, queue->msg_token, PAGE_SIZE, DMA_BIDIRECTIONAL);
-	free_page((unsigned long)queue->msgs.handle);
+	dma_free_noncoherent(dev, PAGE_SIZE, queue->msgs.handle,
+			     queue->msg_token, DMA_BIDIRECTIONAL);
 	queue->msgs.handle = NULL;
 
 	ibmvfc_free_event_pool(vhost, queue);
@@ -5663,19 +5663,11 @@  static int ibmvfc_alloc_queue(struct ibmvfc_host *vhost,
 		return -ENOMEM;
 	}
 
-	queue->msgs.handle = (void *)get_zeroed_page(GFP_KERNEL);
+	queue->msgs.handle = dma_alloc_noncoherent(dev, PAGE_SIZE, &queue->msg_token,
+						   DMA_BIDIRECTIONAL, GFP_KERNEL);
 	if (!queue->msgs.handle)
 		return -ENOMEM;
 
-	queue->msg_token = dma_map_single(dev, queue->msgs.handle, PAGE_SIZE,
-					  DMA_BIDIRECTIONAL);
-
-	if (dma_mapping_error(dev, queue->msg_token)) {
-		free_page((unsigned long)queue->msgs.handle);
-		queue->msgs.handle = NULL;
-		return -ENOMEM;
-	}
-
 	queue->cur = 0;
 	queue->fmt = fmt;
 	queue->size = PAGE_SIZE / fmt_size;
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index ea8e01f49cba..68409c298c74 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -151,10 +151,8 @@  static void ibmvscsi_release_crq_queue(struct crq_queue *queue,
 			msleep(100);
 		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
 	} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
-	dma_unmap_single(hostdata->dev,
-			 queue->msg_token,
-			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
-	free_page((unsigned long)queue->msgs);
+	dma_free_noncoherent(hostdata->dev, PAGE_SIZE,
+			     queue->msgs, queue->msg_token, DMA_BIDIRECTIONAL);
 }
 
 /**
@@ -331,18 +329,12 @@  static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
 	int retrc;
 	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
 
-	queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
-
-	if (!queue->msgs)
-		goto malloc_failed;
 	queue->size = PAGE_SIZE / sizeof(*queue->msgs);
-
-	queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
-					  queue->size * sizeof(*queue->msgs),
-					  DMA_BIDIRECTIONAL);
-
-	if (dma_mapping_error(hostdata->dev, queue->msg_token))
-		goto map_failed;
+	queue->msgs = dma_alloc_noncoherent(hostdata->dev,
+					    PAGE_SIZE, &queue->msg_token,
+					    DMA_BIDIRECTIONAL, GFP_KERNEL);
+	if (!queue->msg)
+		goto malloc_failed;
 
 	gather_partition_info();
 	set_adapter_info(hostdata);
@@ -395,11 +387,8 @@  static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
 		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
 	} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
       reg_crq_failed:
-	dma_unmap_single(hostdata->dev,
-			 queue->msg_token,
-			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
-      map_failed:
-	free_page((unsigned long)queue->msgs);
+	dma_free_noncoherent(hostdata->dev, PAGE_SIZE, queue->msg,
+			     queue->msg_token, DMA_BIDIRECTIONAL);
       malloc_failed:
 	return -1;
 }