pcmcia: CompactFlash driver for PA Semi Electra boards
[pv_ops_mirror.git] / drivers / scsi / arm / scsi.h
blob21ba57155beacd1617440b4e9b0506c708f72d01
1 /*
2 * linux/drivers/acorn/scsi/scsi.h
4 * Copyright (C) 2002 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * Commonly used scsi driver functions.
13 #include <linux/scatterlist.h>
15 #define BELT_AND_BRACES
18 * The scatter-gather list handling. This contains all
19 * the yucky stuff that needs to be fixed properly.
21 static inline int copy_SCp_to_sg(struct scatterlist *sg, struct scsi_pointer *SCp, int max)
23 int bufs = SCp->buffers_residual;
25 BUG_ON(bufs + 1 > max);
27 sg_set_buf(sg, SCp->ptr, SCp->this_residual);
29 if (bufs)
30 memcpy(sg + 1, SCp->buffer + 1,
31 sizeof(struct scatterlist) * bufs);
32 return bufs + 1;
35 static inline int next_SCp(struct scsi_pointer *SCp)
37 int ret = SCp->buffers_residual;
38 if (ret) {
39 SCp->buffer++;
40 SCp->buffers_residual--;
41 SCp->ptr = (char *)
42 (page_address(SCp->buffer->page) +
43 SCp->buffer->offset);
44 SCp->this_residual = SCp->buffer->length;
45 } else {
46 SCp->ptr = NULL;
47 SCp->this_residual = 0;
49 return ret;
52 static inline unsigned char get_next_SCp_byte(struct scsi_pointer *SCp)
54 char c = *SCp->ptr;
56 SCp->ptr += 1;
57 SCp->this_residual -= 1;
59 return c;
62 static inline void put_next_SCp_byte(struct scsi_pointer *SCp, unsigned char c)
64 *SCp->ptr = c;
65 SCp->ptr += 1;
66 SCp->this_residual -= 1;
69 static inline void init_SCp(struct scsi_cmnd *SCpnt)
71 memset(&SCpnt->SCp, 0, sizeof(struct scsi_pointer));
73 if (SCpnt->use_sg) {
74 unsigned long len = 0;
75 int buf;
77 SCpnt->SCp.buffer = (struct scatterlist *) SCpnt->request_buffer;
78 SCpnt->SCp.buffers_residual = SCpnt->use_sg - 1;
79 SCpnt->SCp.ptr = (char *)
80 (page_address(SCpnt->SCp.buffer->page) +
81 SCpnt->SCp.buffer->offset);
82 SCpnt->SCp.this_residual = SCpnt->SCp.buffer->length;
83 SCpnt->SCp.phase = SCpnt->request_bufflen;
85 #ifdef BELT_AND_BRACES
87 * Calculate correct buffer length. Some commands
88 * come in with the wrong request_bufflen.
90 for (buf = 0; buf <= SCpnt->SCp.buffers_residual; buf++)
91 len += SCpnt->SCp.buffer[buf].length;
93 if (SCpnt->request_bufflen != len)
94 printk(KERN_WARNING "scsi%d.%c: bad request buffer "
95 "length %d, should be %ld\n", SCpnt->device->host->host_no,
96 '0' + SCpnt->device->id, SCpnt->request_bufflen, len);
97 SCpnt->request_bufflen = len;
98 #endif
99 } else {
100 SCpnt->SCp.ptr = (unsigned char *)SCpnt->request_buffer;
101 SCpnt->SCp.this_residual = SCpnt->request_bufflen;
102 SCpnt->SCp.phase = SCpnt->request_bufflen;
106 * If the upper SCSI layers pass a buffer, but zero length,
107 * we aren't interested in the buffer pointer.
109 if (SCpnt->SCp.this_residual == 0 && SCpnt->SCp.ptr) {
110 #if 0 //def BELT_AND_BRACES
111 printk(KERN_WARNING "scsi%d.%c: zero length buffer passed for "
112 "command ", SCpnt->host->host_no, '0' + SCpnt->target);
113 __scsi_print_command(SCpnt->cmnd);
114 #endif
115 SCpnt->SCp.ptr = NULL;