From: Harvey Harrison <harvey.harrison@gmail.com>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Matthew Wilcox <matthew@wil.cx>,
Andrew Morton <akpm@linux-foundation.org>,
linux-scsi <linux-scsi@vger.kernel.org>
Subject: [RFC PATCH-mm] scsi: use unaligned endian helpers rather than byteshifting
Date: Wed, 03 Dec 2008 11:37:23 -0800 [thread overview]
Message-ID: <1228333043.5412.35.camel@brick> (raw)
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
---
Depends on the unaligned access work in -mm. Just so you can see what the
transition would look like. See in particular the READ/WRITE6 bits
as just reading the full 32 bits and masking ends up being better on
lots of arches. (x86/powerpc/SH at least)
drivers/scsi/aacraid/aachba.c | 126 +++++++++-------------------------------
1 files changed, 29 insertions(+), 97 deletions(-)
diff --git a/drivers/scsi/aacraid/aachba.c b/drivers/scsi/aacraid/aachba.c
index 90d1d08..5cdbc7d 100644
--- a/drivers/scsi/aacraid/aachba.c
+++ b/drivers/scsi/aacraid/aachba.c
@@ -33,6 +33,7 @@
#include <linux/blkdev.h>
#include <asm/uaccess.h>
#include <linux/highmem.h> /* For flush_kernel_dcache_page */
+#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
@@ -1479,29 +1480,18 @@ static void io_callback(void *context, struct fib * fibptr)
switch (scsicmd->cmnd[0]) {
case WRITE_6:
case READ_6:
- lba = ((scsicmd->cmnd[1] & 0x1F) << 16) |
- (scsicmd->cmnd[2] << 8) | scsicmd->cmnd[3];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[0]) & 0x1fffff;
break;
case WRITE_16:
case READ_16:
- lba = ((u64)scsicmd->cmnd[2] << 56) |
- ((u64)scsicmd->cmnd[3] << 48) |
- ((u64)scsicmd->cmnd[4] << 40) |
- ((u64)scsicmd->cmnd[5] << 32) |
- ((u64)scsicmd->cmnd[6] << 24) |
- (scsicmd->cmnd[7] << 16) |
- (scsicmd->cmnd[8] << 8) | scsicmd->cmnd[9];
+ lba = load_be64_noalign((__be64 *)&scsicmd->cmnd[2]);
break;
case WRITE_12:
case READ_12:
- lba = ((u64)scsicmd->cmnd[2] << 24) |
- (scsicmd->cmnd[3] << 16) |
- (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
break;
default:
- lba = ((u64)scsicmd->cmnd[2] << 24) |
- (scsicmd->cmnd[3] << 16) |
- (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
break;
}
printk(KERN_DEBUG
@@ -1576,34 +1566,20 @@ static int aac_read(struct scsi_cmnd * scsicmd)
case READ_16:
dprintk((KERN_DEBUG "aachba: received a read(16) command on id %d.\n", scmd_id(scsicmd)));
- lba = ((u64)scsicmd->cmnd[2] << 56) |
- ((u64)scsicmd->cmnd[3] << 48) |
- ((u64)scsicmd->cmnd[4] << 40) |
- ((u64)scsicmd->cmnd[5] << 32) |
- ((u64)scsicmd->cmnd[6] << 24) |
- (scsicmd->cmnd[7] << 16) |
- (scsicmd->cmnd[8] << 8) | scsicmd->cmnd[9];
- count = (scsicmd->cmnd[10] << 24) |
- (scsicmd->cmnd[11] << 16) |
- (scsicmd->cmnd[12] << 8) | scsicmd->cmnd[13];
+ lba = load_be64_noalign((__be64 *)&scsicmd->cmnd[2]);
+ count = load_be32_noalign((__be32 *)&scsicmd->cmnd[10]);
break;
case READ_12:
dprintk((KERN_DEBUG "aachba: received a read(12) command on id %d.\n", scmd_id(scsicmd)));
- lba = ((u64)scsicmd->cmnd[2] << 24) |
- (scsicmd->cmnd[3] << 16) |
- (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
- count = (scsicmd->cmnd[6] << 24) |
- (scsicmd->cmnd[7] << 16) |
- (scsicmd->cmnd[8] << 8) | scsicmd->cmnd[9];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
+ count = load_be32_noalign((__be32 *)&scsicmd->cmnd[6]);
break;
default:
dprintk((KERN_DEBUG "aachba: received a read(10) command on id %d.\n", scmd_id(scsicmd)));
- lba = ((u64)scsicmd->cmnd[2] << 24) |
- (scsicmd->cmnd[3] << 16) |
- (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
- count = (scsicmd->cmnd[7] << 8) | scsicmd->cmnd[8];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
+ count = load_be16_noalign((__be16 *)&scsicmd->cmnd[7]);
break;
}
dprintk((KERN_DEBUG "aac_read[cpu %d]: lba = %llu, t = %ld.\n",
@@ -1661,28 +1637,19 @@ static int aac_write(struct scsi_cmnd * scsicmd)
} else if (scsicmd->cmnd[0] == WRITE_16) { /* 16 byte command */
dprintk((KERN_DEBUG "aachba: received a write(16) command on id %d.\n", scmd_id(scsicmd)));
- lba = ((u64)scsicmd->cmnd[2] << 56) |
- ((u64)scsicmd->cmnd[3] << 48) |
- ((u64)scsicmd->cmnd[4] << 40) |
- ((u64)scsicmd->cmnd[5] << 32) |
- ((u64)scsicmd->cmnd[6] << 24) |
- (scsicmd->cmnd[7] << 16) |
- (scsicmd->cmnd[8] << 8) | scsicmd->cmnd[9];
- count = (scsicmd->cmnd[10] << 24) | (scsicmd->cmnd[11] << 16) |
- (scsicmd->cmnd[12] << 8) | scsicmd->cmnd[13];
+ lba = load_be64_noalign((__be64 *)&scsicmd->cmnd[2]);
+ count = load_be32_noalign((__be32 *)&scsicmd->cmnd[10]);
fua = scsicmd->cmnd[1] & 0x8;
} else if (scsicmd->cmnd[0] == WRITE_12) { /* 12 byte command */
dprintk((KERN_DEBUG "aachba: received a write(12) command on id %d.\n", scmd_id(scsicmd)));
- lba = ((u64)scsicmd->cmnd[2] << 24) | (scsicmd->cmnd[3] << 16)
- | (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
- count = (scsicmd->cmnd[6] << 24) | (scsicmd->cmnd[7] << 16)
- | (scsicmd->cmnd[8] << 8) | scsicmd->cmnd[9];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
+ count = load_be32_noalign((__be32 *)&scsicmd->cmnd[6]);
fua = scsicmd->cmnd[1] & 0x8;
} else {
dprintk((KERN_DEBUG "aachba: received a write(10) command on id %d.\n", scmd_id(scsicmd)));
- lba = ((u64)scsicmd->cmnd[2] << 24) | (scsicmd->cmnd[3] << 16) | (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
- count = (scsicmd->cmnd[7] << 8) | scsicmd->cmnd[8];
+ lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
+ count = load_be16_noalign((__be16 *)&scsicmd->cmnd[7]);
fua = scsicmd->cmnd[1] & 0x8;
}
dprintk((KERN_DEBUG "aac_write[cpu %d]: lba = %llu, t = %ld.\n",
@@ -1770,9 +1737,8 @@ static int aac_synchronize(struct scsi_cmnd *scsicmd)
struct scsi_device *sdev = scsicmd->device;
int active = 0;
struct aac_dev *aac;
- u64 lba = ((u64)scsicmd->cmnd[2] << 24) | (scsicmd->cmnd[3] << 16) |
- (scsicmd->cmnd[4] << 8) | scsicmd->cmnd[5];
- u32 count = (scsicmd->cmnd[7] << 8) | scsicmd->cmnd[8];
+ u64 lba = load_be32_noalign((__be32 *)&scsicmd->cmnd[2]);
+ u32 count = load_be16_noalign((__be16 *)&scsicmd->cmnd[7]);
unsigned long flags;
/*
@@ -1786,41 +1752,19 @@ static int aac_synchronize(struct scsi_cmnd *scsicmd)
u32 cmnd_count;
if (cmd->cmnd[0] == WRITE_6) {
- cmnd_lba = ((cmd->cmnd[1] & 0x1F) << 16) |
- (cmd->cmnd[2] << 8) |
- cmd->cmnd[3];
+ cmnd_lba = load_be32_noalign((__be32 *)&cmd->cmnd[0]) & 0x1fffff;
cmnd_count = cmd->cmnd[4];
if (cmnd_count == 0)
cmnd_count = 256;
} else if (cmd->cmnd[0] == WRITE_16) {
- cmnd_lba = ((u64)cmd->cmnd[2] << 56) |
- ((u64)cmd->cmnd[3] << 48) |
- ((u64)cmd->cmnd[4] << 40) |
- ((u64)cmd->cmnd[5] << 32) |
- ((u64)cmd->cmnd[6] << 24) |
- (cmd->cmnd[7] << 16) |
- (cmd->cmnd[8] << 8) |
- cmd->cmnd[9];
- cmnd_count = (cmd->cmnd[10] << 24) |
- (cmd->cmnd[11] << 16) |
- (cmd->cmnd[12] << 8) |
- cmd->cmnd[13];
+ cmnd_lba = load_be64_noalign((__be64 *)&cmd->cmnd[2]);
+ cmnd_count = load_be32_noalign((__be32 *)&cmd->cmnd[10]);
} else if (cmd->cmnd[0] == WRITE_12) {
- cmnd_lba = ((u64)cmd->cmnd[2] << 24) |
- (cmd->cmnd[3] << 16) |
- (cmd->cmnd[4] << 8) |
- cmd->cmnd[5];
- cmnd_count = (cmd->cmnd[6] << 24) |
- (cmd->cmnd[7] << 16) |
- (cmd->cmnd[8] << 8) |
- cmd->cmnd[9];
+ cmnd_lba = load_be32_noalign((__be32 *)&cmd->cmnd[2]);
+ cmnd_count = load_be32_noalign((__be32 *)&cmd->cmnd[6]);
} else if (cmd->cmnd[0] == WRITE_10) {
- cmnd_lba = ((u64)cmd->cmnd[2] << 24) |
- (cmd->cmnd[3] << 16) |
- (cmd->cmnd[4] << 8) |
- cmd->cmnd[5];
- cmnd_count = (cmd->cmnd[7] << 8) |
- cmd->cmnd[8];
+ cmnd_lba = load_be32_noalign((__be32 *)&cmd->cmnd[2]);
+ cmnd_count = load_be16_noalign((__be16 *)&cmd->cmnd[7]);
} else
continue;
if (((cmnd_lba + cmnd_count) < lba) ||
@@ -2136,23 +2080,14 @@ int aac_scsi_cmd(struct scsi_cmnd * scsicmd)
dprintk((KERN_DEBUG "READ CAPACITY_16 command.\n"));
capacity = fsa_dev_ptr[cid].size - 1;
- cp[0] = (capacity >> 56) & 0xff;
- cp[1] = (capacity >> 48) & 0xff;
- cp[2] = (capacity >> 40) & 0xff;
- cp[3] = (capacity >> 32) & 0xff;
- cp[4] = (capacity >> 24) & 0xff;
- cp[5] = (capacity >> 16) & 0xff;
- cp[6] = (capacity >> 8) & 0xff;
- cp[7] = (capacity >> 0) & 0xff;
+ store_be64_noalign((__be64 *)&cp[0], capacity);
cp[8] = 0;
cp[9] = 0;
cp[10] = 2;
cp[11] = 0;
cp[12] = 0;
- alloc_len = ((scsicmd->cmnd[10] << 24)
- + (scsicmd->cmnd[11] << 16)
- + (scsicmd->cmnd[12] << 8) + scsicmd->cmnd[13]);
+ alloc_len = load_be32_noalign((__be32 *)&scsicmd->cmnd[10]);
alloc_len = min_t(size_t, alloc_len, sizeof(cp));
scsi_sg_copy_from_buffer(scsicmd, cp, alloc_len);
@@ -2180,10 +2115,7 @@ int aac_scsi_cmd(struct scsi_cmnd * scsicmd)
else
capacity = (u32)-1;
- cp[0] = (capacity >> 24) & 0xff;
- cp[1] = (capacity >> 16) & 0xff;
- cp[2] = (capacity >> 8) & 0xff;
- cp[3] = (capacity >> 0) & 0xff;
+ store_be32_noalign((__be32 *)&cp[0], capacity);
cp[4] = 0;
cp[5] = 0;
cp[6] = 2;
--
1.6.1.rc1.262.gb6810
next reply other threads:[~2008-12-03 19:38 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-12-03 19:37 Harvey Harrison [this message]
2008-12-03 20:15 ` [RFC PATCH-mm] scsi: use unaligned endian helpers rather than byteshifting Matthew Wilcox
2008-12-03 20:27 ` Harvey Harrison
2008-12-03 20:33 ` James Bottomley
2008-12-05 9:07 ` Harvey Harrison
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