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scsi: ata: Use unsigned int for cmd's type in ioctls in scsi_host_template

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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>
This commit is contained in:
Nathan Chancellor
2019-02-07 09:07:20 -07:00
committed by Martin K. Petersen
parent 42fb055a57
commit 6f4e626fb0
19 changed files with 54 additions and 44 deletions
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5
include/linux/libata.h
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@@ -1122,10 +1122,11 @@ extern int ata_host_activate(struct ata_host *host, int irq,
extern void ata_host_detach(struct ata_host *host);
extern void ata_host_init(struct ata_host *, struct device *, struct ata_port_operations *);
extern int ata_scsi_detect(struct scsi_host_template *sht);
extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
extern int ata_scsi_ioctl(struct scsi_device *dev, unsigned int cmd,
void __user *arg);
extern int ata_scsi_queuecmd(struct Scsi_Host *h, struct scsi_cmnd *cmd);
extern int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *dev,
int cmd, void __user *arg);
unsigned int cmd, void __user *arg);
extern void ata_sas_port_destroy(struct ata_port *);
extern struct ata_port *ata_sas_port_alloc(struct ata_host *,
struct ata_port_info *, struct Scsi_Host *);