[PATCH 08/13] hpsa: get rid of type/attribute/direction bit field where possible

Don Brace
2014-11-14T23:25:29Z

From: Stephen M. Cameron <stephenmcameron@gmail.com>

Using bit fields for hardware command fields isn't portable and
relies on assumptions about how the compiler lays out the bits.
We can fix this in the driver's internal command structure, but the
ioctl interface we can't change because it is part of the
userland ABI.

Signed-off-by: Don Brace <don.brace@pmcs.com>
Reviewed-by: Webb Scales <webb.scales@hp.com>
---
drivers/scsi/hpsa.c | 58 ++++++++++++++++++++++++-----------------------
drivers/scsi/hpsa_cmd.h | 18 +++++++++++----
2 files changed, 42 insertions(+), 34 deletions(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index fe1b589..95c34a5 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -4019,17 +4019,18 @@ static int hpsa_scsi_queue_command_lck(struct scsi_cmnd *cmd,
BUG_ON(cmd->cmd_len > sizeof(c->Request.CDB));
c->Request.CDBLen = cmd->cmd_len;
memcpy(c->Request.CDB, cmd->cmnd, cmd->cmd_len);
- c->Request.Type.Type = TYPE_CMD;
- c->Request.Type.Attribute = ATTR_SIMPLE;
switch (cmd->sc_data_direction) {
case DMA_TO_DEVICE:
- c->Request.Type.Direction = XFER_WRITE;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(TYPE_CMD, ATTR_SIMPLE, XFER_WRITE);
break;
case DMA_FROM_DEVICE:
- c->Request.Type.Direction = XFER_READ;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(TYPE_CMD, ATTR_SIMPLE, XFER_READ);
break;
case DMA_NONE:
- c->Request.Type.Direction = XFER_NONE;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(TYPE_CMD, ATTR_SIMPLE, XFER_NONE);
break;
case DMA_BIDIRECTIONAL:
/* This can happen if a buggy application does a scsi passthru
@@ -4037,7 +4038,8 @@ static int hpsa_scsi_queue_command_lck(struct scsi_cmnd *cmd,
* ../scsi/scsi_ioctl.c:scsi_ioctl_send_command() )
*/

- c->Request.Type.Direction = XFER_RSVD;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(TYPE_CMD, ATTR_SIMPLE, XFER_RSVD);
/* This is technically wrong, and hpsa controllers should
* reject it with CMD_INVALID, which is the most correct
* response, but non-fibre backends appear to let it
@@ -5257,7 +5259,6 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
c->Header.tag = c->busaddr;
memcpy(c->Header.LUN.LunAddrBytes, scsi3addr, 8);

- c->Request.Type.Type = cmd_type;
if (cmd_type == TYPE_CMD) {
switch (cmd) {
case HPSA_INQUIRY:
@@ -5267,8 +5268,8 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
c->Request.CDB[2] = (page_code & 0xff);
}
c->Request.CDBLen = 6;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_READ;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type, ATTR_SIMPLE, XFER_READ);
c->Request.Timeout = 0;
c->Request.CDB[0] = HPSA_INQUIRY;
c->Request.CDB[4] = size & 0xFF;
@@ -5279,8 +5280,8 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
mode = 00 target = 0. Nothing to write.
*/
c->Request.CDBLen = 12;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_READ;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type, ATTR_SIMPLE, XFER_READ);
c->Request.Timeout = 0;
c->Request.CDB[0] = cmd;
c->Request.CDB[6] = (size >> 24) & 0xFF; /* MSB */
@@ -5290,8 +5291,9 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
break;
case HPSA_CACHE_FLUSH:
c->Request.CDBLen = 12;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_WRITE;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type,
+ ATTR_SIMPLE, XFER_WRITE);
c->Request.Timeout = 0;
c->Request.CDB[0] = BMIC_WRITE;
c->Request.CDB[6] = BMIC_CACHE_FLUSH;
@@ -5300,14 +5302,14 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
break;
case TEST_UNIT_READY:
c->Request.CDBLen = 6;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_NONE;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type, ATTR_SIMPLE, XFER_NONE);
c->Request.Timeout = 0;
break;
case HPSA_GET_RAID_MAP:
c->Request.CDBLen = 12;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_READ;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type, ATTR_SIMPLE, XFER_READ);
c->Request.Timeout = 0;
c->Request.CDB[0] = HPSA_CISS_READ;
c->Request.CDB[1] = cmd;
@@ -5318,8 +5320,8 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
break;
case BMIC_SENSE_CONTROLLER_PARAMETERS:
c->Request.CDBLen = 10;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_READ;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type, ATTR_SIMPLE, XFER_READ);
c->Request.Timeout = 0;
c->Request.CDB[0] = BMIC_READ;
c->Request.CDB[6] = BMIC_SENSE_CONTROLLER_PARAMETERS;
@@ -5336,9 +5338,8 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,

case HPSA_DEVICE_RESET_MSG:
c->Request.CDBLen = 16;
- c->Request.Type.Type = 1; /* It is a MSG not a CMD */
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_NONE;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type, ATTR_SIMPLE, XFER_NONE);
c->Request.Timeout = 0; /* Don't time out */
memset(&c->Request.CDB[0], 0, sizeof(c->Request.CDB));
c->Request.CDB[0] = cmd;
@@ -5357,9 +5358,9 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
tlower = (u32) (a->Header.tag >> 32);
tupper = (u32) (a->Header.tag & 0x0ffffffffULL);
c->Request.CDBLen = 16;
- c->Request.Type.Type = TYPE_MSG;
- c->Request.Type.Attribute = ATTR_SIMPLE;
- c->Request.Type.Direction = XFER_WRITE;
+ c->Request.type_attr_dir =
+ TYPE_ATTR_DIR(cmd_type,
+ ATTR_SIMPLE, XFER_WRITE);
c->Request.Timeout = 0; /* Don't time out */
c->Request.CDB[0] = HPSA_TASK_MANAGEMENT;
c->Request.CDB[1] = HPSA_TMF_ABORT_TASK;
@@ -5389,7 +5390,7 @@ static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
BUG();
}

- switch (c->Request.Type.Direction) {
+ switch (GET_DIR(c->Request.type_attr_dir)) {
case XFER_READ:
pci_dir = PCI_DMA_FROMDEVICE;
break;
@@ -5747,9 +5748,8 @@ static int hpsa_message(struct pci_dev *pdev, unsigned char opcode,
memset(&cmd->CommandHeader.LUN.LunAddrBytes, 0, 8);

cmd->Request.CDBLen = 16;
- cmd->Request.Type.Type = TYPE_MSG;
- cmd->Request.Type.Attribute = ATTR_HEADOFQUEUE;
- cmd->Request.Type.Direction = XFER_NONE;
+ cmd->Request.type_attr_dir =
+ TYPE_ATTR_DIR(TYPE_MSG, ATTR_HEADOFQUEUE, XFER_NONE);
cmd->Request.Timeout = 0; /* Don't time out */
cmd->Request.CDB[0] = opcode;
cmd->Request.CDB[1] = type;
diff --git a/drivers/scsi/hpsa_cmd.h b/drivers/scsi/hpsa_cmd.h
index 575eda8..cb988c4 100644
--- a/drivers/scsi/hpsa_cmd.h
+++ b/drivers/scsi/hpsa_cmd.h
@@ -320,11 +320,19 @@ struct CommandListHeader {

struct RequestBlock {
u8 CDBLen;
- struct {
- u8 Type:3;
- u8 Attribute:3;
- u8 Direction:2;
- } Type;
+ /*
+ * type_attr_dir:
+ * type: low 3 bits
+ * attr: middle 3 bits
+ * dir: high 2 bits
+ */
+ u8 type_attr_dir;
+#define TYPE_ATTR_DIR(t, a, d) ((((d) & 0x03) << 6) |\
+ (((a) & 0x07) << 3) |\
+ ((t) & 0x07))
+#define GET_TYPE(tad) ((tad) & 0x07)
+#define GET_ATTR(tad) (((tad) >> 3) & 0x07)
+#define GET_DIR(tad) (((tad) >> 6) & 0x03)
u16 Timeout;
u8 CDB[16];
};