Re: [dpdk-dev] [PATCH 6/6] eal: Fix interface of pci_map_resource()

[Tetsuya Mukawa <mukawa@igel.co.jp>]

On 2015/03/20 18:53, Iremonger, Bernard wrote:
>> -----Original Message-----
>> From: Tetsuya Mukawa [mailto:mukawa@igel.co.jp]
>> Sent: Tuesday, March 17, 2015 9:31 AM
>> To: dev@dpdk.org
>> Cc: Iremonger, Bernard; Richardson, Bruce; Tetsuya Mukawa
>> Subject: [PATCH 6/6] eal: Fix interface of pci_map_resource()
>>
>> The function is implemented in both linuxapp and bsdapp, but interface is different. The patch fixes
>> the function of bsdapp to do same as linuxapp. After applying it, file descriptor should be opened and
>> closed out of pci_map_resource().
>> Also, remove redundant error messages from linuxapp.
>>
>> Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>
>> ---
>>  lib/librte_eal/bsdapp/eal/eal_pci.c       | 109 ++++++++++++++++++------------
>>  lib/librte_eal/linuxapp/eal/eal_pci_uio.c |  21 +++---
>>  2 files changed, 75 insertions(+), 55 deletions(-)
>>
>> diff --git a/lib/librte_eal/bsdapp/eal/eal_pci.c b/lib/librte_eal/bsdapp/eal/eal_pci.c
>> index 08b91b4..21a3d79 100644
>> --- a/lib/librte_eal/bsdapp/eal/eal_pci.c
>> +++ b/lib/librte_eal/bsdapp/eal/eal_pci.c
>> @@ -100,7 +100,7 @@ struct mapped_pci_resource {
>>
>>  	struct rte_pci_addr pci_addr;
>>  	char path[PATH_MAX];
>> -	size_t nb_maps;
>> +	int nb_maps;
>>  	struct pci_map maps[PCI_MAX_RESOURCE];  };
>>
>> @@ -122,47 +122,30 @@ pci_unbind_kernel_driver(struct rte_pci_device *dev __rte_unused)
>>
>>  /* map a particular resource from a file */  static void * -pci_map_resource(void *requested_addr,
>> const char *devname, off_t offset,
>> -		 size_t size)
>> +pci_map_resource(void *requested_addr, int fd, off_t offset, size_t size,
>> +		 int additional_flags)
>>  {
>> -	int fd;
>>  	void *mapaddr;
>>
>> -	/*
>> -	 * open devname, to mmap it
>> -	 */
>> -	fd = open(devname, O_RDWR);
>> -	if (fd < 0) {
>> -		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
>> -			devname, strerror(errno));
>> -		goto fail;
>> -	}
>> -
>>  	/* Map the PCI memory resource of device */
>>  	mapaddr = mmap(requested_addr, size, PROT_READ | PROT_WRITE,
>> -			MAP_SHARED, fd, offset);
>> -	close(fd);
>> -	if (mapaddr == MAP_FAILED ||
>> -			(requested_addr != NULL && mapaddr != requested_addr)) {
>> -		RTE_LOG(ERR, EAL, "%s(): cannot mmap(%s(%d), %p, 0x%lx, 0x%lx):"
>> -			" %s (%p)\n", __func__, devname, fd, requested_addr,
>> +			MAP_SHARED | additional_flags, fd, offset);
>> +	if (mapaddr == MAP_FAILED) {
>> +		RTE_LOG(ERR, EAL,
>> +			"%s(): cannot mmap(%d, %p, 0x%lx, 0x%lx): %s (%p)\n",
>> +			__func__, fd, requested_addr,
>>  			(unsigned long)size, (unsigned long)offset,
>>  			strerror(errno), mapaddr);
>> -		goto fail;
> Hi Tetsuya,
>
> Previously pci_map_resource() returned NULL  when MAP_FAILED occurred.
> It now returns MAP_FAILED.
> Where pci_map_resource() is called it should now check for MAP_FAILED instead of NULL, or else the return value of NULL should be restored.
> There is another comment below.

Hi Bernard,

I appreciate for your comment.
Yes it should be. I will fix it.

Regards,
Tetsuya

>
>
>> -	}
>> -
>> -	RTE_LOG(DEBUG, EAL, "  PCI memory mapped at %p\n", mapaddr);
>> +	} else
>> +		RTE_LOG(DEBUG, EAL, "  PCI memory mapped at %p\n", mapaddr);
>>
>>  	return mapaddr;
>> -
>> -fail:
>> -	return NULL;
>>  }
>>
>>  static int
>>  pci_uio_map_secondary(struct rte_pci_device *dev)  {
>> -	size_t i;
>> +	int i, fd;
>>  	struct mapped_pci_resource *uio_res;
>>  	struct mapped_pci_res_list *uio_res_list =
>>  			RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list); @@ -170,19
>> +153,34 @@ pci_uio_map_secondary(struct rte_pci_device *dev)
>>  	TAILQ_FOREACH(uio_res, uio_res_list, next) {
>>
>>  		/* skip this element if it doesn't match our PCI address */
>> -		if (memcmp(&uio_res->pci_addr, &dev->addr, sizeof(dev->addr)))
>> +		if (rte_eal_compare_pci_addr(&uio_res->pci_addr, &dev->addr))
>>  			continue;
>>
>>  		for (i = 0; i != uio_res->nb_maps; i++) {
>> -			if (pci_map_resource(uio_res->maps[i].addr,
>> -					     uio_res->path,
>> -					     (off_t)uio_res->maps[i].offset,
>> -					     (size_t)uio_res->maps[i].size)
>> -			    != uio_res->maps[i].addr) {
>> +			/*
>> +			 * open devname, to mmap it
>> +			 */
>> +			fd = open(uio_res->maps[i].path, O_RDWR);
>> +			if (fd < 0) {
>> +				RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
>> +					uio_res->maps[i].path, strerror(errno));
>> +				return -1;
>> +			}
>> +
>> +			void *mapaddr = pci_map_resource(uio_res->maps[i].addr,
>> +					fd, (off_t)uio_res->maps[i].offset,
>> +					(size_t)uio_res->maps[i].size, 0);
>> +			if (mapaddr != uio_res->maps[i].addr) {
>>  				RTE_LOG(ERR, EAL,
>> -					"Cannot mmap device resource\n");
>> +						"Cannot mmap device resource "
>> +						"file %s to address: %p\n",
>> +						uio_res->maps[i].path,
>> +						uio_res->maps[i].addr);
>> +				close(fd);
>>  				return -1;
>>  			}
>> +			/* fd is not needed in slave process, close it */
>> +			close(fd);
>>  		}
>>  		return 0;
>>  	}
>> @@ -248,24 +246,43 @@ pci_uio_map_resource(struct rte_pci_device *dev)
>>
>>  	maps = uio_res->maps;
>>  	for (i = 0, map_idx = 0; i != PCI_MAX_RESOURCE; i++) {
>> +		int fd;
>>
>>  		/* skip empty BAR */
>>  		if ((phaddr = dev->mem_resource[i].phys_addr) == 0)
>>  			continue;
>>
>> +		/* allocate memory to keep path */
>> +		maps[map_idx].path = rte_malloc(NULL, strlen(devname) + 1, 0);
>> +		if (maps[map_idx].path == NULL) {
>> +			RTE_LOG(ERR, EAL, "Cannot allocate memory for "
>> +					"path: %s\n", strerror(errno));
>> +			goto fail0;
>> +		}
>> +
>> +		/*
>> +		 * open resource file, to mmap it
>> +		 */
>> +		fd = open(devname, O_RDWR);
>> +		if (fd < 0) {
>> +			RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
>> +					devname, strerror(errno));
>> +			goto fail1;
>> +		}
>> +
>>  		/* if matching map is found, then use it */
>>  		offset = i * pagesz;
>> -		maps[map_idx].offset = offset;
>> +		mapaddr = pci_map_resource(NULL, fd, (off_t)offset,
>> +					(size_t)dev->mem_resource[i].len, 0);
>> +		close(fd);
>> +		if (mapaddr == NULL)
> The check here should be for MAP_FAILED instead of NULL.
>
> Regards,
> Bernard.
>
>
>> +			goto fail1;
>> +
>>  		maps[map_idx].phaddr = dev->mem_resource[i].phys_addr;
>>  		maps[map_idx].size = dev->mem_resource[i].len;
>> -		mapaddr = pci_map_resource(NULL, devname, (off_t)offset,
>> -					(size_t)maps[map_idx].size);
>> -		if ((maps[map_idx].addr != NULL) || (mapaddr == NULL)) {
>> -			rte_free(uio_res);
>> -			return -1;
>> -		}
>> -
>>  		maps[map_idx].addr = mapaddr;
>> +		maps[map_idx].offset = offset;
>> +		strcpy(maps[map_idx].path, devname);
>>  		map_idx++;
>>  		dev->mem_resource[i].addr = mapaddr;
>>  	}
>> @@ -275,6 +292,12 @@ pci_uio_map_resource(struct rte_pci_device *dev)
>>  	TAILQ_INSERT_TAIL(uio_res_list, uio_res, next);
>>
>>  	return 0;
>> +
>> +fail1:
>> +	rte_free(maps[map_idx].path);
>> +fail0:
>> +	rte_free(uio_res);
>> +	return -1;
>>  }
>>
>>  /* Scan one pci sysfs entry, and fill the devices list from it. */ diff --git
>> a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
>> index 5044884..9eeaebb 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
>> @@ -116,17 +116,11 @@ pci_uio_map_secondary(struct rte_pci_device *dev)
>>  					fd, (off_t)uio_res->maps[i].offset,
>>  					(size_t)uio_res->maps[i].size, 0);
>>  			if (mapaddr != uio_res->maps[i].addr) {
>> -				if (mapaddr == MAP_FAILED)
>> -					RTE_LOG(ERR, EAL,
>> -							"Cannot mmap device resource file %s: %s\n",
>> -							uio_res->maps[i].path,
>> -							strerror(errno));
>> -				else
>> -					RTE_LOG(ERR, EAL,
>> -							"Cannot mmap device resource file %s to
>> address: %p\n",
>> -							uio_res->maps[i].path,
>> -							uio_res->maps[i].addr);
>> -
>> +				RTE_LOG(ERR, EAL,
>> +						"Cannot mmap device resource "
>> +						"file %s to address: %p\n",
>> +						uio_res->maps[i].path,
>> +						uio_res->maps[i].addr);
>>  				close(fd);
>>  				return -1;
>>  			}
>> @@ -348,8 +342,11 @@ pci_uio_map_resource(struct rte_pci_device *dev)
>>
>>  		/* allocate memory to keep path */
>>  		maps[map_idx].path = rte_malloc(NULL, strlen(devname) + 1, 0);
>> -		if (maps[map_idx].path == NULL)
>> +		if (maps[map_idx].path == NULL) {
>> +			RTE_LOG(ERR, EAL, "Cannot allocate memory for "
>> +					"path: %s\n", strerror(errno));
>>  			goto fail0;
>> +		}
>>
>>  		/*
>>  		 * open resource file, to mmap it
>> --
>> 1.9.1