By
- rearranging the elements of the scsi_pointer
- shrinking and moving the eh_eflags element
- turning sc_data_direction into an unsigned char
- moving tag
we achieve a size reduction in scsi_cmnd of 376 to 352 bytes on x86-64
and from 272 to 260 bytes on i386.
Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>
---
include/scsi/scsi_cmnd.h | 19 ++++++++-----------
1 files changed, 8 insertions(+), 11 deletions(-)
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index 047ffe6..04fe0d8 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -13,22 +13,21 @@ struct Scsi_Host;
struct scsi_device;
struct scsi_data_buffer {
+ struct scatterlist* sglist;
unsigned length;
int resid;
unsigned short sg_count;
unsigned short alloc_sg_count;
- struct scatterlist* sglist;
};
/* embedded in scsi_cmnd */
struct scsi_pointer {
char *ptr; /* data pointer */
- int this_residual; /* left in this buffer */
struct scatterlist *buffer; /* which buffer */
+ dma_addr_t dma_handle;
+ int this_residual; /* left in this buffer */
int buffers_residual; /* how many buffers left */
- dma_addr_t dma_handle;
-
volatile int Status;
volatile int Message;
volatile int have_data_in;
@@ -40,7 +39,6 @@ struct scsi_cmnd {
struct scsi_device *device;
struct list_head list; /* scsi_cmnd participates in queue lists */
struct list_head eh_entry; /* entry for the host eh_cmd_q */
- int eh_eflags; /* Used by error handlr */
/*
* A SCSI Command is assigned a nonzero serial_number before passed
@@ -64,7 +62,9 @@ struct scsi_cmnd {
int timeout_per_command;
unsigned char cmd_len;
- enum dma_data_direction sc_data_direction;
+ unsigned char eh_eflags; /* Used by error handler */
+ unsigned char sc_data_direction; /* enum dma_data_direction */
+ unsigned char tag; /* SCSI-II queued command tag */
/* These elements define the operation we are about to perform */
#define MAX_COMMAND_SIZE 16
@@ -82,8 +82,7 @@ struct scsi_cmnd {
reconnects. Probably == sector
size */
- struct request *request; /* The command we are
- working on */
+ struct request *request; /* The command we are working on */
#define SCSI_SENSE_BUFFERSIZE 96
unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE];
@@ -111,8 +110,6 @@ struct scsi_cmnd {
int result; /* Status code from lower level driver */
- unsigned char tag; /* SCSI-II queued command tag */
-
union {
struct scsi_data_buffer sdb;
/*
@@ -121,11 +118,11 @@ struct scsi_cmnd {
* of struct scsi_data_buffer members.
*/
struct {
+ void __deprecated *request_buffer;
unsigned __deprecated request_bufflen;
int __deprecated resid;
unsigned short __deprecated use_sg;
unsigned short __deprecated place_holder_sg_alloc;
- void __deprecated *request_buffer;
};
};
};
--
1.4.4.2
-
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