[PATCH] scsi: sd: Make protection lookup tables static

From: John Garry
Date: Mon Jan 07 2019 - 09:41:18 EST


Currently the protection lookup tables in sd_prot_flag_mask() and
sd_prot_op() are declared non-static. As such, they will be rebuilt for
each respective function call.

Optimise by making them static.

This saves ~100B object code for sd.c:

Before:
text data bss dec hex filename
25403 1024 16 26443 674b drivers/scsi/sd.o

After:
text data bss dec hex filename
25299 1024 16 26339 66e3 drivers/scsi/sd.o

Signed-off-by: John Garry <john.garry@xxxxxxxxxx>

diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index 1d63f3a..89e6d42 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -195,15 +195,15 @@ static inline sector_t sectors_to_logical(struct scsi_device *sdev, sector_t sec
static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
{
/* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
- const unsigned int ops[] = { /* wrt dix dif */
- SCSI_PROT_NORMAL, /* 0 0 0 */
- SCSI_PROT_READ_STRIP, /* 0 0 1 */
- SCSI_PROT_READ_INSERT, /* 0 1 0 */
- SCSI_PROT_READ_PASS, /* 0 1 1 */
- SCSI_PROT_NORMAL, /* 1 0 0 */
- SCSI_PROT_WRITE_INSERT, /* 1 0 1 */
- SCSI_PROT_WRITE_STRIP, /* 1 1 0 */
- SCSI_PROT_WRITE_PASS, /* 1 1 1 */
+ static const unsigned int ops[] = { /* wrt dix dif */
+ SCSI_PROT_NORMAL, /* 0 0 0 */
+ SCSI_PROT_READ_STRIP, /* 0 0 1 */
+ SCSI_PROT_READ_INSERT, /* 0 1 0 */
+ SCSI_PROT_READ_PASS, /* 0 1 1 */
+ SCSI_PROT_NORMAL, /* 1 0 0 */
+ SCSI_PROT_WRITE_INSERT, /* 1 0 1 */
+ SCSI_PROT_WRITE_STRIP, /* 1 1 0 */
+ SCSI_PROT_WRITE_PASS, /* 1 1 1 */
};

return ops[write << 2 | dix << 1 | dif];
@@ -215,7 +215,7 @@ static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
*/
static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
{
- const unsigned int flag_mask[] = {
+ static const unsigned int flag_mask[] = {
[SCSI_PROT_NORMAL] = 0,

[SCSI_PROT_READ_STRIP] = SCSI_PROT_TRANSFER_PI |
--
1.9.1