[v3,11/32] cxlflash: Refine host/device attributes

Implement the following suggestions and add two new attributes
to allow for debugging the port LUN table.

 - use scnprintf() instead of snprintf()
 - use DEVICE_ATTR_RO and DEVICE_ATTR_RW

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 180 +++++++++++++++++++++++++++++++++----------
 1 file changed, 138 insertions(+), 42 deletions(-)

Somehow the Suggested-by tag was dropped from this one. Adding it back.

-matt

> On Sep 24, 2015, at 2:39 PM, Matthew R. Ochs <mrochs@linux.vnet.ibm.com> wrote:
> 
> Implement the following suggestions and add two new attributes
> to allow for debugging the port LUN table.
> 
> - use scnprintf() instead of snprintf()
> - use DEVICE_ATTR_RO and DEVICE_ATTR_RW
> 
> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Suggested-by: Shane Seymour <shane.seymour@hp.com>

> ---
> drivers/scsi/cxlflash/main.c | 180 +++++++++++++++++++++++++++++++++----------
> 1 file changed, 138 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
> index 226cefe..b44212b 100644
> --- a/drivers/scsi/cxlflash/main.c
> +++ b/drivers/scsi/cxlflash/main.c
> @@ -1995,33 +1995,24 @@ static int cxlflash_change_queue_depth(struct scsi_device *sdev, int qdepth)
> 
> /**
>  * cxlflash_show_port_status() - queries and presents the current port status
> - * @dev:	Generic device associated with the host owning the port.
> - * @attr:	Device attribute representing the port.
> + * @port:	Desired port for status reporting.
> + * @afu:	AFU owning the specified port.
>  * @buf:	Buffer of length PAGE_SIZE to report back port status in ASCII.
>  *
>  * Return: The size of the ASCII string returned in @buf.
>  */
> -static ssize_t cxlflash_show_port_status(struct device *dev,
> -					 struct device_attribute *attr,
> -					 char *buf)
> +static ssize_t cxlflash_show_port_status(u32 port, struct afu *afu, char *buf)
> {
> -	struct Scsi_Host *shost = class_to_shost(dev);
> -	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> -	struct afu *afu = cfg->afu;
> -
> 	char *disp_status;
> -	int rc;
> -	u32 port;
> 	u64 status;
> -	u64 *fc_regs;
> +	__be64 __iomem *fc_regs;
> 
> -	rc = kstrtouint((attr->attr.name + 4), 10, &port);
> -	if (rc || (port >= NUM_FC_PORTS))
> +	if (port >= NUM_FC_PORTS)
> 		return 0;
> 
> 	fc_regs = &afu->afu_map->global.fc_regs[port][0];
> -	status =
> -	    (readq_be(&fc_regs[FC_MTIP_STATUS / 8]) & FC_MTIP_STATUS_MASK);
> +	status = readq_be(&fc_regs[FC_MTIP_STATUS / 8]);
> +	status &= FC_MTIP_STATUS_MASK;
> 
> 	if (status == FC_MTIP_STATUS_ONLINE)
> 		disp_status = "online";
> @@ -2030,31 +2021,69 @@ static ssize_t cxlflash_show_port_status(struct device *dev,
> 	else
> 		disp_status = "unknown";
> 
> -	return snprintf(buf, PAGE_SIZE, "%s\n", disp_status);
> +	return scnprintf(buf, PAGE_SIZE, "%s\n", disp_status);
> +}
> +
> +/**
> + * port0_show() - queries and presents the current status of port 0
> + * @dev:	Generic device associated with the host owning the port.
> + * @attr:	Device attribute representing the port.
> + * @buf:	Buffer of length PAGE_SIZE to report back port status in ASCII.
> + *
> + * Return: The size of the ASCII string returned in @buf.
> + */
> +static ssize_t port0_show(struct device *dev,
> +			  struct device_attribute *attr,
> +			  char *buf)
> +{
> +	struct Scsi_Host *shost = class_to_shost(dev);
> +	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> +	struct afu *afu = cfg->afu;
> +
> +	return cxlflash_show_port_status(0, afu, buf);
> }
> 
> /**
> - * cxlflash_show_lun_mode() - presents the current LUN mode of the host
> + * port1_show() - queries and presents the current status of port 1
> + * @dev:	Generic device associated with the host owning the port.
> + * @attr:	Device attribute representing the port.
> + * @buf:	Buffer of length PAGE_SIZE to report back port status in ASCII.
> + *
> + * Return: The size of the ASCII string returned in @buf.
> + */
> +static ssize_t port1_show(struct device *dev,
> +			  struct device_attribute *attr,
> +			  char *buf)
> +{
> +	struct Scsi_Host *shost = class_to_shost(dev);
> +	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> +	struct afu *afu = cfg->afu;
> +
> +	return cxlflash_show_port_status(1, afu, buf);
> +}
> +
> +/**
> + * lun_mode_show() - presents the current LUN mode of the host
>  * @dev:	Generic device associated with the host.
> - * @attr:	Device attribute representing the lun mode.
> + * @attr:	Device attribute representing the LUN mode.
>  * @buf:	Buffer of length PAGE_SIZE to report back the LUN mode in ASCII.
>  *
>  * Return: The size of the ASCII string returned in @buf.
>  */
> -static ssize_t cxlflash_show_lun_mode(struct device *dev,
> -				      struct device_attribute *attr, char *buf)
> +static ssize_t lun_mode_show(struct device *dev,
> +			     struct device_attribute *attr, char *buf)
> {
> 	struct Scsi_Host *shost = class_to_shost(dev);
> 	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> 	struct afu *afu = cfg->afu;
> 
> -	return snprintf(buf, PAGE_SIZE, "%u\n", afu->internal_lun);
> +	return scnprintf(buf, PAGE_SIZE, "%u\n", afu->internal_lun);
> }
> 
> /**
> - * cxlflash_store_lun_mode() - sets the LUN mode of the host
> + * lun_mode_store() - sets the LUN mode of the host
>  * @dev:	Generic device associated with the host.
> - * @attr:	Device attribute representing the lun mode.
> + * @attr:	Device attribute representing the LUN mode.
>  * @buf:	Buffer of length PAGE_SIZE containing the LUN mode in ASCII.
>  * @count:	Length of data resizing in @buf.
>  *
> @@ -2073,9 +2102,9 @@ static ssize_t cxlflash_show_lun_mode(struct device *dev,
>  *
>  * Return: The size of the ASCII string returned in @buf.
>  */
> -static ssize_t cxlflash_store_lun_mode(struct device *dev,
> -				       struct device_attribute *attr,
> -				       const char *buf, size_t count)
> +static ssize_t lun_mode_store(struct device *dev,
> +			      struct device_attribute *attr,
> +			      const char *buf, size_t count)
> {
> 	struct Scsi_Host *shost = class_to_shost(dev);
> 	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> @@ -2094,58 +2123,125 @@ static ssize_t cxlflash_store_lun_mode(struct device *dev,
> }
> 
> /**
> - * cxlflash_show_ioctl_version() - presents the hosts current ioctl version
> + * ioctl_version_show() - presents the current ioctl version of the host
>  * @dev:	Generic device associated with the host.
>  * @attr:	Device attribute representing the ioctl version.
>  * @buf:	Buffer of length PAGE_SIZE to report back the ioctl version.
>  *
>  * Return: The size of the ASCII string returned in @buf.
>  */
> -static ssize_t cxlflash_show_ioctl_version(struct device *dev,
> -					   struct device_attribute *attr,
> -					   char *buf)
> +static ssize_t ioctl_version_show(struct device *dev,
> +				  struct device_attribute *attr, char *buf)
> {
> 	return scnprintf(buf, PAGE_SIZE, "%u\n", DK_CXLFLASH_VERSION_0);
> }
> 
> /**
> - * cxlflash_show_dev_mode() - presents the current mode of the device
> + * cxlflash_show_port_lun_table() - queries and presents the port LUN table
> + * @port:	Desired port for status reporting.
> + * @afu:	AFU owning the specified port.
> + * @buf:	Buffer of length PAGE_SIZE to report back port status in ASCII.
> + *
> + * Return: The size of the ASCII string returned in @buf.
> + */
> +static ssize_t cxlflash_show_port_lun_table(u32 port,
> +					    struct afu *afu,
> +					    char *buf)
> +{
> +	int i;
> +	ssize_t bytes = 0;
> +	__be64 __iomem *fc_port;
> +
> +	if (port >= NUM_FC_PORTS)
> +		return 0;
> +
> +	fc_port = &afu->afu_map->global.fc_port[port][0];
> +
> +	for (i = 0; i < CXLFLASH_NUM_VLUNS; i++)
> +		bytes += scnprintf(buf + bytes, PAGE_SIZE - bytes,
> +				   "%03d: %016llX\n", i, readq_be(&fc_port[i]));
> +	return bytes;
> +}
> +
> +/**
> + * port0_lun_table_show() - presents the current LUN table of port 0
> + * @dev:	Generic device associated with the host owning the port.
> + * @attr:	Device attribute representing the port.
> + * @buf:	Buffer of length PAGE_SIZE to report back port status in ASCII.
> + *
> + * Return: The size of the ASCII string returned in @buf.
> + */
> +static ssize_t port0_lun_table_show(struct device *dev,
> +				    struct device_attribute *attr,
> +				    char *buf)
> +{
> +	struct Scsi_Host *shost = class_to_shost(dev);
> +	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> +	struct afu *afu = cfg->afu;
> +
> +	return cxlflash_show_port_lun_table(0, afu, buf);
> +}
> +
> +/**
> + * port1_lun_table_show() - presents the current LUN table of port 1
> + * @dev:	Generic device associated with the host owning the port.
> + * @attr:	Device attribute representing the port.
> + * @buf:	Buffer of length PAGE_SIZE to report back port status in ASCII.
> + *
> + * Return: The size of the ASCII string returned in @buf.
> + */
> +static ssize_t port1_lun_table_show(struct device *dev,
> +				    struct device_attribute *attr,
> +				    char *buf)
> +{
> +	struct Scsi_Host *shost = class_to_shost(dev);
> +	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata;
> +	struct afu *afu = cfg->afu;
> +
> +	return cxlflash_show_port_lun_table(1, afu, buf);
> +}
> +
> +/**
> + * mode_show() - presents the current mode of the device
>  * @dev:	Generic device associated with the device.
>  * @attr:	Device attribute representing the device mode.
>  * @buf:	Buffer of length PAGE_SIZE to report back the dev mode in ASCII.
>  *
>  * Return: The size of the ASCII string returned in @buf.
>  */
> -static ssize_t cxlflash_show_dev_mode(struct device *dev,
> -				      struct device_attribute *attr, char *buf)
> +static ssize_t mode_show(struct device *dev,
> +			 struct device_attribute *attr, char *buf)
> {
> 	struct scsi_device *sdev = to_scsi_device(dev);
> 
> -	return snprintf(buf, PAGE_SIZE, "%s\n",
> -			sdev->hostdata ? "superpipe" : "legacy");
> +	return scnprintf(buf, PAGE_SIZE, "%s\n",
> +			 sdev->hostdata ? "superpipe" : "legacy");
> }
> 
> /*
>  * Host attributes
>  */
> -static DEVICE_ATTR(port0, S_IRUGO, cxlflash_show_port_status, NULL);
> -static DEVICE_ATTR(port1, S_IRUGO, cxlflash_show_port_status, NULL);
> -static DEVICE_ATTR(lun_mode, S_IRUGO | S_IWUSR, cxlflash_show_lun_mode,
> -		   cxlflash_store_lun_mode);
> -static DEVICE_ATTR(ioctl_version, S_IRUGO, cxlflash_show_ioctl_version, NULL);
> +static DEVICE_ATTR_RO(port0);
> +static DEVICE_ATTR_RO(port1);
> +static DEVICE_ATTR_RW(lun_mode);
> +static DEVICE_ATTR_RO(ioctl_version);
> +static DEVICE_ATTR_RO(port0_lun_table);
> +static DEVICE_ATTR_RO(port1_lun_table);
> 
> static struct device_attribute *cxlflash_host_attrs[] = {
> 	&dev_attr_port0,
> 	&dev_attr_port1,
> 	&dev_attr_lun_mode,
> 	&dev_attr_ioctl_version,
> +	&dev_attr_port0_lun_table,
> +	&dev_attr_port1_lun_table,
> 	NULL
> };
> 
> /*
>  * Device attributes
>  */
> -static DEVICE_ATTR(mode, S_IRUGO, cxlflash_show_dev_mode, NULL);
> +static DEVICE_ATTR_RO(mode);
> 
> static struct device_attribute *cxlflash_dev_attrs[] = {
> 	&dev_attr_mode,
> -- 
> 2.1.0
> 
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Reviewed-by: Brian King <brking@linux.vnet.ibm.com>