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authorJohn Garry <john.garry@huawei.com>2019-01-08 23:14:52 +0800
committerMartin K. Petersen <martin.petersen@oracle.com>2019-01-08 22:29:32 -0500
commit082c2cd2030e5e9322c835f577fdc9acff41ee5b (patch)
tree98eb52338bc7ddbce55b3a55b17ef122e47d3b98 /drivers/scsi/sd.c
parent1afb4b8524797f95b15480a6654780571cde4e56 (diff)
downloadlinux-082c2cd2030e5e9322c835f577fdc9acff41ee5b.tar.bz2
scsi: sd: Make protection lookup tables static and relocate functions
Currently the protection lookup tables in sd_prot_flag_mask() and sd_prot_op() are declared as 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 In addition, since those same functions are declared in sd.h, but each are only referenced in sd.c, relocate them to that same c file. The inline specifier is dropped also, since gcc should be able to make the decision to inline. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/sd.c')
-rw-r--r--drivers/scsi/sd.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index a1a44f52e0e8..c6ca3d915925 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -659,6 +659,68 @@ static int sd_sec_submit(void *data, u16 spsp, u8 secp, void *buffer,
}
#endif /* CONFIG_BLK_SED_OPAL */
+/*
+ * Look up the DIX operation based on whether the command is read or
+ * write and whether dix and dif are enabled.
+ */
+static unsigned int sd_prot_op(bool write, bool dix, bool dif)
+{
+ /* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
+ 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];
+}
+
+/*
+ * Returns a mask of the protection flags that are valid for a given DIX
+ * operation.
+ */
+static unsigned int sd_prot_flag_mask(unsigned int prot_op)
+{
+ static const unsigned int flag_mask[] = {
+ [SCSI_PROT_NORMAL] = 0,
+
+ [SCSI_PROT_READ_STRIP] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT,
+
+ [SCSI_PROT_READ_INSERT] = SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+
+ [SCSI_PROT_READ_PASS] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+
+ [SCSI_PROT_WRITE_INSERT] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_REF_INCREMENT,
+
+ [SCSI_PROT_WRITE_STRIP] = SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+
+ [SCSI_PROT_WRITE_PASS] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+ };
+
+ return flag_mask[prot_op];
+}
+
static unsigned char sd_setup_protect_cmnd(struct scsi_cmnd *scmd,
unsigned int dix, unsigned int dif)
{