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, 9 insertions, 6 deletions

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 5284444fdd10..f044e7d10d63 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -251,10 +251,11 @@ static int number_of_controllers;
 
 static irqreturn_t do_hpsa_intr_intx(int irq, void *dev_id);
 static irqreturn_t do_hpsa_intr_msi(int irq, void *dev_id);
-static int hpsa_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
+static int hpsa_ioctl(struct scsi_device *dev, unsigned int cmd,
+		      void __user *arg);
 
 #ifdef CONFIG_COMPAT
-static int hpsa_compat_ioctl(struct scsi_device *dev, int cmd,
+static int hpsa_compat_ioctl(struct scsi_device *dev, unsigned int cmd,
 	void __user *arg);
 #endif
 
@@ -6127,7 +6128,7 @@ static void cmd_free(struct ctlr_info *h, struct CommandList *c)
 
 #ifdef CONFIG_COMPAT
 
-static int hpsa_ioctl32_passthru(struct scsi_device *dev, int cmd,
+static int hpsa_ioctl32_passthru(struct scsi_device *dev, unsigned int cmd,
 	void __user *arg)
 {
 	IOCTL32_Command_struct __user *arg32 =
@@ -6164,7 +6165,7 @@ static int hpsa_ioctl32_passthru(struct scsi_device *dev, int cmd,
 }
 
 static int hpsa_ioctl32_big_passthru(struct scsi_device *dev,
-	int cmd, void __user *arg)
+	unsigned int cmd, void __user *arg)
 {
 	BIG_IOCTL32_Command_struct __user *arg32 =
 	    (BIG_IOCTL32_Command_struct __user *) arg;
@@ -6201,7 +6202,8 @@ static int hpsa_ioctl32_big_passthru(struct scsi_device *dev,
 	return err;
 }
 
-static int hpsa_compat_ioctl(struct scsi_device *dev, int cmd, void __user *arg)
+static int hpsa_compat_ioctl(struct scsi_device *dev, unsigned int cmd,
+			     void __user *arg)
 {
 	switch (cmd) {
 	case CCISS_GETPCIINFO:
@@ -6521,7 +6523,8 @@ static void check_ioctl_unit_attention(struct ctlr_info *h,
 /*
  * ioctl
  */
-static int hpsa_ioctl(struct scsi_device *dev, int cmd, void __user *arg)
+static int hpsa_ioctl(struct scsi_device *dev, unsigned int cmd,
+		      void __user *arg)
 {
 	struct ctlr_info *h;
 	void __user *argp = (void __user *)arg;