From 6f4e626fb0cc93d50b49b79c2ee33bd769ee57f0 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 7 Feb 2019 09:07:20 -0700 Subject: scsi: ata: Use unsigned int for cmd's type in ioctls in scsi_host_template Clang warns several times in the scsi subsystem (trimmed for brevity): drivers/scsi/hpsa.c:6209:7: warning: overflow converting case value to switch condition type (2147762695 to 18446744071562347015) [-Wswitch] case CCISS_GETBUSTYPES: ^ drivers/scsi/hpsa.c:6208:7: warning: overflow converting case value to switch condition type (2147762694 to 18446744071562347014) [-Wswitch] case CCISS_GETHEARTBEAT: ^ The root cause is that the _IOC macro can generate really large numbers, which don't fit into type 'int', which is used for the cmd parameter in the ioctls in scsi_host_template. My research into how GCC and Clang are handling this at a low level didn't prove fruitful. However, looking at the rest of the kernel tree, all ioctls use an 'unsigned int' for the cmd parameter, which will fit all of the _IOC values in the scsi/ata subsystems. Make that change because none of the ioctls expect a negative value for any command, it brings the ioctls inline with the reset of the kernel, and it removes ambiguity, which is never good when dealing with compilers. Link: https://github.com/ClangBuiltLinux/linux/issues/85 Link: https://github.com/ClangBuiltLinux/linux/issues/154 Link: https://github.com/ClangBuiltLinux/linux/issues/157 Signed-off-by: Nathan Chancellor Acked-by: Bradley Grove Acked-by: Don Brace Reviewed-by: Bart Van Assche Tested-by: Nick Desaulniers Reviewed-by: Christoph Hellwig Signed-off-by: Martin K. Petersen --- drivers/ata/libata-scsi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/ata') diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 3d4887d0e84a..6291f1dbf342 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -778,7 +778,7 @@ static int ata_ioc32(struct ata_port *ap) } int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev, - int cmd, void __user *arg) + unsigned int cmd, void __user *arg) { unsigned long val; int rc = -EINVAL; @@ -829,7 +829,8 @@ int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev, } EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl); -int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg) +int ata_scsi_ioctl(struct scsi_device *scsidev, unsigned int cmd, + void __user *arg) { return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host), scsidev, cmd, arg); -- cgit v1.2.3