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 <natechancellor@gmail.com>
Acked-by: Bradley Grove <bgrove@attotech.com>
Acked-by: Don Brace <don.brace@microsemi.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
index dd701d5243b1..22ecacffeca6 100644
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -616,7 +616,8 @@ static struct device_attribute *aac_dev_attrs[] = {
 	NULL,
 };
 
-static int aac_ioctl(struct scsi_device *sdev, int cmd, void __user * arg)
+static int aac_ioctl(struct scsi_device *sdev, unsigned int cmd,
+		     void __user *arg)
 {
 	struct aac_dev *dev = (struct aac_dev *)sdev->host->hostdata;
 	if (!capable(CAP_SYS_RAWIO))
@@ -1205,7 +1206,8 @@ static long aac_compat_do_ioctl(struct aac_dev *dev, unsigned cmd, unsigned long
 	return ret;
 }
 
-static int aac_compat_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
+static int aac_compat_ioctl(struct scsi_device *sdev, unsigned int cmd,
+			    void __user *arg)
 {
 	struct aac_dev *dev = (struct aac_dev *)sdev->host->hostdata;
 	if (!capable(CAP_SYS_RAWIO))