diff options
| author | Xi Wang <xi.wang@gmail.com> | 2012-11-16 14:40:03 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-01-17 08:50:44 -0800 |
| commit | 3814b31a89b1fbb5c6f92c11c8371a2e4c97d2f1 (patch) | |
| tree | 6d9e245958e29c1b91b6c5ff1cb970069679c7ee /drivers/scsi | |
| parent | 8f735b2774f5e200a65c5fe9143fb431023a5267 (diff) | |
SCSI: mvsas: fix undefined bit shift
commit beecadea1b8d67f591b13f7099559f32f3fd601d upstream.
The macro bit(n) is defined as ((u32)1 << n), and thus it doesn't work
with n >= 32, such as in mvs_94xx_assign_reg_set():
if (i >= 32) {
mvi->sata_reg_set |= bit(i);
...
}
The shift ((u32)1 << n) with n >= 32 also leads to undefined behavior.
The result varies depending on the architecture.
This patch changes bit(n) to do a 64-bit shift. It also simplifies
mv_ffc64() using __ffs64(), since invoking ffz() with ~0 is undefined.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Acked-by: Xiangliang Yu <yuxiangl@marvell.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/mvsas/mv_94xx.h | 14 | ||||
| -rw-r--r-- | drivers/scsi/mvsas/mv_sas.h | 2 |
2 files changed, 3 insertions, 13 deletions
diff --git a/drivers/scsi/mvsas/mv_94xx.h b/drivers/scsi/mvsas/mv_94xx.h index 8f7eb4f2114..487aa6f9741 100644 --- a/drivers/scsi/mvsas/mv_94xx.h +++ b/drivers/scsi/mvsas/mv_94xx.h @@ -258,21 +258,11 @@ enum sas_sata_phy_regs { #define SPI_ADDR_VLD_94XX (1U << 1) #define SPI_CTRL_SpiStart_94XX (1U << 0) -#define mv_ffc(x) ffz(x) - static inline int mv_ffc64(u64 v) { - int i; - i = mv_ffc((u32)v); - if (i >= 0) - return i; - i = mv_ffc((u32)(v>>32)); - - if (i != 0) - return 32 + i; - - return -1; + u64 x = ~v; + return x ? __ffs64(x) : -1; } #define r_reg_set_enable(i) \ diff --git a/drivers/scsi/mvsas/mv_sas.h b/drivers/scsi/mvsas/mv_sas.h index c04a4f5b597..da249553858 100644 --- a/drivers/scsi/mvsas/mv_sas.h +++ b/drivers/scsi/mvsas/mv_sas.h @@ -69,7 +69,7 @@ extern struct kmem_cache *mvs_task_list_cache; #define DEV_IS_EXPANDER(type) \ ((type == EDGE_DEV) || (type == FANOUT_DEV)) -#define bit(n) ((u32)1 << n) +#define bit(n) ((u64)1 << n) #define for_each_phy(__lseq_mask, __mc, __lseq) \ for ((__mc) = (__lseq_mask), (__lseq) = 0; \ |