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>

3 files changed, 10 insertions, 12 deletions

diff --git a/drivers/scsi/esas2r/esas2r.h b/drivers/scsi/esas2r/esas2r.h
index 858c3b33db78..7f43b95f4e94 100644
--- a/drivers/scsi/esas2r/esas2r.h
+++ b/drivers/scsi/esas2r/esas2r.h
@@ -965,8 +965,8 @@ struct esas2r_adapter {
 const char *esas2r_info(struct Scsi_Host *);
 int esas2r_write_params(struct esas2r_adapter *a, struct esas2r_request *rq,
 			struct esas2r_sas_nvram *data);
-int esas2r_ioctl_handler(void *hostdata, int cmd, void __user *arg);
-int esas2r_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
+int esas2r_ioctl_handler(void *hostdata, unsigned int cmd, void __user *arg);
+int esas2r_ioctl(struct scsi_device *dev, unsigned int cmd, void __user *arg);
 u8 handle_hba_ioctl(struct esas2r_adapter *a,
 		    struct atto_ioctl *ioctl_hba);
 int esas2r_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd);
diff --git a/drivers/scsi/esas2r/esas2r_ioctl.c b/drivers/scsi/esas2r/esas2r_ioctl.c
index 34bcc8c04ff4..3d130523c288 100644
--- a/drivers/scsi/esas2r/esas2r_ioctl.c
+++ b/drivers/scsi/esas2r/esas2r_ioctl.c
@@ -1274,7 +1274,7 @@ int esas2r_write_params(struct esas2r_adapter *a, struct esas2r_request *rq,
 
 
 /* This function only cares about ATTO-specific ioctls (atto_express_ioctl) */
-int esas2r_ioctl_handler(void *hostdata, int cmd, void __user *arg)
+int esas2r_ioctl_handler(void *hostdata, unsigned int cmd, void __user *arg)
 {
 	struct atto_express_ioctl *ioctl = NULL;
 	struct esas2r_adapter *a;
@@ -1292,9 +1292,8 @@ int esas2r_ioctl_handler(void *hostdata, int cmd, void __user *arg)
 	ioctl = memdup_user(arg, sizeof(struct atto_express_ioctl));
 	if (IS_ERR(ioctl)) {
 		esas2r_log(ESAS2R_LOG_WARN,
-			   "ioctl_handler access_ok failed for cmd %d, "
-			   "address %p", cmd,
-			   arg);
+			   "ioctl_handler access_ok failed for cmd %u, address %p",
+			   cmd, arg);
 		return PTR_ERR(ioctl);
 	}
 
@@ -1493,7 +1492,7 @@ int esas2r_ioctl_handler(void *hostdata, int cmd, void __user *arg)
 ioctl_done:
 
 	if (err < 0) {
-		esas2r_log(ESAS2R_LOG_WARN, "err %d on ioctl cmd %d", err,
+		esas2r_log(ESAS2R_LOG_WARN, "err %d on ioctl cmd %u", err,
 			   cmd);
 
 		switch (err) {
@@ -1518,9 +1517,8 @@ ioctl_done:
 	err = __copy_to_user(arg, ioctl, sizeof(struct atto_express_ioctl));
 	if (err != 0) {
 		esas2r_log(ESAS2R_LOG_WARN,
-			   "ioctl_handler copy_to_user didn't copy "
-			   "everything (err %d, cmd %d)", err,
-			   cmd);
+			   "ioctl_handler copy_to_user didn't copy everything (err %d, cmd %u)",
+			   err, cmd);
 		kfree(ioctl);
 
 		return -EFAULT;
@@ -1531,7 +1529,7 @@ ioctl_done:
 	return 0;
 }
 
-int esas2r_ioctl(struct scsi_device *sd, int cmd, void __user *arg)
+int esas2r_ioctl(struct scsi_device *sd, unsigned int cmd, void __user *arg)
 {
 	return esas2r_ioctl_handler(sd->host->hostdata, cmd, arg);
 }
diff --git a/drivers/scsi/esas2r/esas2r_main.c b/drivers/scsi/esas2r/esas2r_main.c
index 64397d441bae..fdbda5c05aa0 100644
--- a/drivers/scsi/esas2r/esas2r_main.c
+++ b/drivers/scsi/esas2r/esas2r_main.c
@@ -623,7 +623,7 @@ static int esas2r_proc_major;
 long esas2r_proc_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 {
 	return esas2r_ioctl_handler(esas2r_proc_host->hostdata,
-				    (int)cmd, (void __user *)arg);
+				    cmd, (void __user *)arg);
 }
 
 static void __exit esas2r_exit(void)