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 --- include/scsi/libsas.h | 3 ++- include/scsi/scsi_host.h | 6 ++++-- 2 files changed, 6 insertions(+), 3 deletions(-) (limited to 'include/scsi') diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h index 857086cf7ebf..56b2dba7d911 100644 --- a/include/scsi/libsas.h +++ b/include/scsi/libsas.h @@ -707,7 +707,8 @@ int sas_eh_target_reset_handler(struct scsi_cmnd *cmd); extern void sas_target_destroy(struct scsi_target *); extern int sas_slave_alloc(struct scsi_device *); -extern int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg); +extern int sas_ioctl(struct scsi_device *sdev, unsigned int cmd, + void __user *arg); extern int sas_drain_work(struct sas_ha_struct *ha); extern void sas_ssp_task_response(struct device *dev, struct sas_task *task, diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 6ca954e9f752..4047d68d1b08 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -60,7 +60,8 @@ struct scsi_host_template { * * Status: OPTIONAL */ - int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg); + int (*ioctl)(struct scsi_device *dev, unsigned int cmd, + void __user *arg); #ifdef CONFIG_COMPAT @@ -70,7 +71,8 @@ struct scsi_host_template { * * Status: OPTIONAL */ - int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg); + int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd, + void __user *arg); #endif /* -- cgit v1.2.3-55-g7522