Since snprintf() has the documented, but still rather strange trait of returning the length of the data that *would have been* written to the array if space were available, rather than the arguably more useful length of data *actually* written, it is usually considered wise to use something else instead in order to avoid confusion.
In the case of sysfs call-backs, new wrappers exist that do just that. Link: https://lwn.net/Articles/69419/ Link: https://github.com/KSPP/linux/issues/105 Signed-off-by: Lee Jones <[email protected]> --- Cc: "James E.J. Bottomley" <[email protected]> Cc: "Martin K. Petersen" <[email protected]> Cc: [email protected] Cc: [email protected] --- drivers/scsi/arcmsr/arcmsr_attr.c | 40 ++++++++----------------------- 1 file changed, 10 insertions(+), 30 deletions(-) diff --git a/drivers/scsi/arcmsr/arcmsr_attr.c b/drivers/scsi/arcmsr/arcmsr_attr.c index baeb5e7956902..c430c835503be 100644 --- a/drivers/scsi/arcmsr/arcmsr_attr.c +++ b/drivers/scsi/arcmsr/arcmsr_attr.c @@ -258,9 +258,7 @@ static ssize_t arcmsr_attr_host_driver_version(struct device *dev, struct device_attribute *attr, char *buf) { - return snprintf(buf, PAGE_SIZE, - "%s\n", - ARCMSR_DRIVER_VERSION); + return sysfs_emit(buf, "%s\n", ARCMSR_DRIVER_VERSION); } static ssize_t @@ -270,9 +268,7 @@ arcmsr_attr_host_driver_posted_cmd(struct device *dev, struct Scsi_Host *host = class_to_shost(dev); struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - atomic_read(&acb->ccboutstandingcount)); + return sysfs_emit(buf, "%4d\n", atomic_read(&acb->ccboutstandingcount)); } static ssize_t @@ -282,9 +278,7 @@ arcmsr_attr_host_driver_reset(struct device *dev, struct Scsi_Host *host = class_to_shost(dev); struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - acb->num_resets); + return sysfs_emit(buf, "%4d\n", acb->num_resets); } static ssize_t @@ -294,9 +288,7 @@ arcmsr_attr_host_driver_abort(struct device *dev, struct Scsi_Host *host = class_to_shost(dev); struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - acb->num_aborts); + return sysfs_emit(buf, "%4d\n", acb->num_aborts); } static ssize_t @@ -306,9 +298,7 @@ arcmsr_attr_host_fw_model(struct device *dev, struct device_attribute *attr, struct Scsi_Host *host = class_to_shost(dev); struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%s\n", - acb->firm_model); + return sysfs_emit(buf, "%s\n", acb->firm_model); } static ssize_t @@ -319,9 +309,7 @@ arcmsr_attr_host_fw_version(struct device *dev, struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%s\n", - acb->firm_version); + return sysfs_emit(buf, "%s\n", acb->firm_version); } static ssize_t @@ -332,9 +320,7 @@ arcmsr_attr_host_fw_request_len(struct device *dev, struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - acb->firm_request_len); + return sysfs_emit(buf, "%4d\n", acb->firm_request_len); } static ssize_t @@ -345,9 +331,7 @@ arcmsr_attr_host_fw_numbers_queue(struct device *dev, struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - acb->firm_numbers_queue); + return sysfs_emit(buf, "%4d\n", acb->firm_numbers_queue); } static ssize_t @@ -358,9 +342,7 @@ arcmsr_attr_host_fw_sdram_size(struct device *dev, struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - acb->firm_sdram_size); + return sysfs_emit(buf, "%4d\n", acb->firm_sdram_size); } static ssize_t @@ -371,9 +353,7 @@ arcmsr_attr_host_fw_hd_channels(struct device *dev, struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata; - return snprintf(buf, PAGE_SIZE, - "%4d\n", - acb->firm_hd_channels); + return sysfs_emit(buf, "%4d\n", acb->firm_hd_channels); } static DEVICE_ATTR(host_driver_version, S_IRUGO, arcmsr_attr_host_driver_version, NULL); -- 2.43.0.594.gd9cf4e227d-goog
