Re: [dpdk-dev] [PATCH v3 2/8] eal: Add pci_uio_map_uio_resource_by_index()

["Iremonger, Bernard" <bernard.iremonger@intel.com>]

> -----Original Message-----
> From: Tetsuya Mukawa [mailto:mukawa@igel.co.jp]
> Sent: Monday, June 29, 2015 3:57 AM
> To: dev@dpdk.org
> Cc: Iremonger, Bernard; david.marchand@6wind.com; Tetsuya.Mukawa
> Subject: [PATCH v3 2/8] eal: Add pci_uio_map_uio_resource_by_index()
> 
> From: "Tetsuya.Mukawa" <mukawa@igel.co.jp>
> 
> This patch adds a new function called pci_uio_map_resource_by_index().
> The function hides how to map uio resource in linuxapp and bsdapp.
> With the function, pci_uio_map_resource() will be more abstracted.
> 
> Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>

Hi Tetsuya,

There are two comments inline below.

> ---
>  lib/librte_eal/bsdapp/eal/eal_pci.c       | 107 +++++++++++++++-----------
>  lib/librte_eal/linuxapp/eal/eal_pci_uio.c | 124 +++++++++++++++++---------
> ----
>  2 files changed, 133 insertions(+), 98 deletions(-)
> 
> diff --git a/lib/librte_eal/bsdapp/eal/eal_pci.c
> b/lib/librte_eal/bsdapp/eal/eal_pci.c
> index 2d9f3a5..61d1fe5 100644
> --- a/lib/librte_eal/bsdapp/eal/eal_pci.c
> +++ b/lib/librte_eal/bsdapp/eal/eal_pci.c
> @@ -240,20 +240,73 @@ close_fd:
>  	return -1;
>  }
> 
> +static int
> +pci_uio_map_uio_resource_by_index(struct rte_pci_device *dev, int
> res_idx,
> +		struct mapped_pci_resource *uio_res, int map_idx) {

The name of this function is a bit long winded, pci_uio_map_resource_by_index() might be better.

> +	int fd;
> +	char *devname;
> +	void *mapaddr;
> +	uint64_t offset;
> +	uint64_t pagesz;
> +	struct pci_map *maps;
> +
> +	if ((dev == NULL) || (uio_res == NULL) || (uio_res->path == NULL))
> +		return -1;
> +
> +	maps = uio_res->maps;
> +	devname = uio_res->path;
> +	pagesz = sysconf(_SC_PAGESIZE);
> +
> +	/* 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));
> +		return -1;
> +	}
> +
> +	/*
> +	 * 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 fail;
> +	}
> +
> +	/* if matching map is found, then use it */
> +	offset = res_idx * pagesz;
> +	mapaddr = pci_map_resource(NULL, fd, (off_t)offset,
> +			(size_t)dev->mem_resource[res_idx].len, 0);
> +	close(fd);
> +	if (mapaddr == MAP_FAILED)
> +		goto fail;
> +
> +	maps[map_idx].phaddr = dev->mem_resource[res_idx].phys_addr;
> +	maps[map_idx].size = dev->mem_resource[res_idx].len;
> +	maps[map_idx].addr = mapaddr;
> +	maps[map_idx].offset = offset;
> +	strcpy(maps[map_idx].path, devname);
> +	dev->mem_resource[res_idx].addr = mapaddr;
> +
> +	return 0;
> +
> +fail:
> +	rte_free(maps[map_idx].path);
> +	return -1;
> +}
> +
>  /* map the PCI resource of a PCI device in virtual memory */  static int
> pci_uio_map_resource(struct rte_pci_device *dev)  {
>  	int i, map_idx, ret;
> -	char *devname;
> -	void *mapaddr;
>  	uint64_t phaddr;
> -	uint64_t offset;
> -	uint64_t pagesz;
>  	struct mapped_pci_resource *uio_res = NULL;
>  	struct mapped_pci_res_list *uio_res_list =
>  		RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);
> -	struct pci_map *maps;
> 
>  	dev->intr_handle.fd = -1;
>  	dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN; @@ -
> 268,53 +321,17 @@ pci_uio_map_resource(struct rte_pci_device *dev)
>  		return ret;
> 
>  	/* Map all BARs */
> -	pagesz = sysconf(_SC_PAGESIZE);
> -	devname = uio_res->path;
> -
> -	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));
> +		ret = pci_uio_map_uio_resource_by_index(dev, i,
> +				uio_res, map_idx);
> +		if (ret != 0)
>  			goto free_uio_res;
> -		}
> 
> -		/*
> -		 * 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));
> -			rte_free(maps[map_idx].path);
> -			goto free_uio_res;
> -		}
> -
> -		/* if matching map is found, then use it */
> -		offset = i * pagesz;
> -		mapaddr = pci_map_resource(NULL, fd, (off_t)offset,
> -					(size_t)dev->mem_resource[i].len,
> 0);
> -		close(fd);
> -		if (mapaddr == MAP_FAILED) {
> -			rte_free(maps[map_idx].path);
> -			goto free_uio_res;
> -		}
> -
> -		maps[map_idx].phaddr = dev->mem_resource[i].phys_addr;
> -		maps[map_idx].size = dev->mem_resource[i].len;
> -		maps[map_idx].addr = mapaddr;
> -		maps[map_idx].offset = offset;
> -		strcpy(maps[map_idx].path, devname);
>  		map_idx++;
> -		dev->mem_resource[i].addr = mapaddr;
>  	}
> 
>  	uio_res->nb_maps = map_idx;
> @@ -325,7 +342,7 @@ pci_uio_map_resource(struct rte_pci_device *dev)
> 
>  free_uio_res:
>  	for (i = 0; i < map_idx; i++)
> -		rte_free(maps[i].path);
> +		rte_free(uio_res->maps[i].path);
>  	rte_free(uio_res);
> 
>  	/* close fd opened by pci_uio_alloc_uio_resource() */ diff --git
> a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
> b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
> index 9e0b617..7da4543 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c
> @@ -333,19 +333,82 @@ close_fd:
>  	return -1;
>  }
> 
> +static int
> +pci_uio_map_uio_resource_by_index(struct rte_pci_device *dev, int
> res_idx,
> +		struct mapped_pci_resource *uio_res, int map_idx) {

The name of this function is a bit long winded, pci_uio_map_resource_by_index() might be better.

Regards,

Bernard.


> +	int fd;
> +	char devname[PATH_MAX]; /* contains the /dev/uioX */
> +	void *mapaddr;
> +	struct rte_pci_addr *loc;
> +	struct pci_map *maps;
> +
> +	if ((dev == NULL) || (uio_res == NULL))
> +		return -1;
> +
> +	loc = &dev->addr;
> +	maps = uio_res->maps;
> +
> +	/* update devname for mmap  */
> +	snprintf(devname, sizeof(devname),
> +			SYSFS_PCI_DEVICES "/" PCI_PRI_FMT
> "/resource%d",
> +			loc->domain, loc->bus, loc->devid,
> +			loc->function, res_idx);
> +
> +	/* 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));
> +		return -1;
> +	}
> +
> +	/*
> +	 * 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 fail;
> +	}
> +
> +	/* try mapping somewhere close to the end of hugepages */
> +	if (pci_map_addr == NULL)
> +		pci_map_addr = pci_find_max_end_va();
> +
> +	mapaddr = pci_map_resource(pci_map_addr, fd, 0,
> +			(size_t)dev->mem_resource[res_idx].len, 0);
> +	close(fd);
> +	if (mapaddr == MAP_FAILED)
> +		goto fail;
> +
> +	pci_map_addr = RTE_PTR_ADD(mapaddr,
> +			(size_t)dev->mem_resource[res_idx].len);
> +
> +	maps[map_idx].phaddr = dev->mem_resource[res_idx].phys_addr;
> +	maps[map_idx].size = dev->mem_resource[res_idx].len;
> +	maps[map_idx].addr = mapaddr;
> +	maps[map_idx].offset = 0;
> +	strcpy(maps[map_idx].path, devname);
> +	dev->mem_resource[res_idx].addr = mapaddr;
> +
> +	return 0;
> +
> +fail:
> +	rte_free(maps[map_idx].path);
> +	return -1;
> +}
> +
>  /* map the PCI resource of a PCI device in virtual memory */  int
> pci_uio_map_resource(struct rte_pci_device *dev)  {
>  	int i, map_idx, ret;
> -	char devname[PATH_MAX]; /* contains the /dev/uioX */
> -	void *mapaddr;
>  	uint64_t phaddr;
> -	struct rte_pci_addr *loc = &dev->addr;
>  	struct mapped_pci_resource *uio_res = NULL;
>  	struct mapped_pci_res_list *uio_res_list =
>  		RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);
> -	struct pci_map *maps;
> 
>  	dev->intr_handle.fd = -1;
>  	dev->intr_handle.uio_cfg_fd = -1;
> @@ -361,63 +424,18 @@ pci_uio_map_resource(struct rte_pci_device *dev)
>  		return ret;
> 
>  	/* Map all BARs */
> -	maps = uio_res->maps;
>  	for (i = 0, map_idx = 0; i != PCI_MAX_RESOURCE; i++) {
> -		int fd;
> -
>  		/* skip empty BAR */
>  		phaddr = dev->mem_resource[i].phys_addr;
>  		if (phaddr == 0)
>  			continue;
> 
> -
> -		/* update devname for mmap  */
> -		snprintf(devname, sizeof(devname),
> -				SYSFS_PCI_DEVICES "/" PCI_PRI_FMT
> "/resource%d",
> -				loc->domain, loc->bus, loc->devid, loc-
> >function,
> -				i);
> -
> -		/* 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 free_uio_res;
> -		}
> -
> -		/*
> -		 * 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));
> -			rte_free(maps[map_idx].path);
> +		ret = pci_uio_map_uio_resource_by_index(dev, i,
> +				uio_res, map_idx);
> +		if (ret != 0)
>  			goto free_uio_res;
> -		}
> -
> -		/* try mapping somewhere close to the end of hugepages */
> -		if (pci_map_addr == NULL)
> -			pci_map_addr = pci_find_max_end_va();
> -
> -		mapaddr = pci_map_resource(pci_map_addr, fd, 0,
> -				(size_t)dev->mem_resource[i].len, 0);
> -		close(fd);
> -		if (mapaddr == MAP_FAILED) {
> -			rte_free(maps[map_idx].path);
> -			goto free_uio_res;
> -		}
> -
> -		pci_map_addr = RTE_PTR_ADD(mapaddr,
> -				(size_t)dev->mem_resource[i].len);
> 
> -		maps[map_idx].phaddr = dev->mem_resource[i].phys_addr;
> -		maps[map_idx].size = dev->mem_resource[i].len;
> -		maps[map_idx].addr = mapaddr;
> -		maps[map_idx].offset = 0;
> -		strcpy(maps[map_idx].path, devname);
>  		map_idx++;
> -		dev->mem_resource[i].addr = mapaddr;
>  	}
> 
>  	uio_res->nb_maps = map_idx;
> @@ -430,7 +448,7 @@ free_uio_res:
>  	for (i = 0; i < map_idx; i++) {
>  		pci_unmap_resource(uio_res->maps[i].addr,
>  				(size_t)uio_res->maps[i].size);
> -		rte_free(maps[i].path);
> +		rte_free(uio_res->maps[i].path);
>  	}
>  	rte_free(uio_res);
> 
> --
> 2.1.4