linux/drivers/scsi/sym53c8xx_2/sym_misc.h

193 lines
5.0 KiB
C
Raw Normal View History

/*
* Device driver for the SYMBIOS/LSILOGIC 53C8XX and 53C1010 family
* of PCI-SCSI IO processors.
*
* Copyright (C) 1999-2001 Gerard Roudier <groudier@free.fr>
*
* This driver is derived from the Linux sym53c8xx driver.
* Copyright (C) 1998-2000 Gerard Roudier
*
* The sym53c8xx driver is derived from the ncr53c8xx driver that had been
* a port of the FreeBSD ncr driver to Linux-1.2.13.
*
* The original ncr driver has been written for 386bsd and FreeBSD by
* Wolfgang Stanglmeier <wolf@cologne.de>
* Stefan Esser <se@mi.Uni-Koeln.de>
* Copyright (C) 1994 Wolfgang Stanglmeier
*
* Other major contributions:
*
* NVRAM detection and reading.
* Copyright (C) 1997 Richard Waltham <dormouse@farsrobt.demon.co.uk>
*
*-----------------------------------------------------------------------------
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef SYM_MISC_H
#define SYM_MISC_H
/*
* A la VMS/CAM-3 queue management.
*/
typedef struct sym_quehead {
struct sym_quehead *flink; /* Forward pointer */
struct sym_quehead *blink; /* Backward pointer */
} SYM_QUEHEAD;
#define sym_que_init(ptr) do { \
(ptr)->flink = (ptr); (ptr)->blink = (ptr); \
} while (0)
static __inline struct sym_quehead *sym_que_first(struct sym_quehead *head)
{
return (head->flink == head) ? 0 : head->flink;
}
static __inline struct sym_quehead *sym_que_last(struct sym_quehead *head)
{
return (head->blink == head) ? 0 : head->blink;
}
static __inline void __sym_que_add(struct sym_quehead * new,
struct sym_quehead * blink,
struct sym_quehead * flink)
{
flink->blink = new;
new->flink = flink;
new->blink = blink;
blink->flink = new;
}
static __inline void __sym_que_del(struct sym_quehead * blink,
struct sym_quehead * flink)
{
flink->blink = blink;
blink->flink = flink;
}
static __inline int sym_que_empty(struct sym_quehead *head)
{
return head->flink == head;
}
static __inline void sym_que_splice(struct sym_quehead *list,
struct sym_quehead *head)
{
struct sym_quehead *first = list->flink;
if (first != list) {
struct sym_quehead *last = list->blink;
struct sym_quehead *at = head->flink;
first->blink = head;
head->flink = first;
last->flink = at;
at->blink = last;
}
}
static __inline void sym_que_move(struct sym_quehead *orig,
struct sym_quehead *dest)
{
struct sym_quehead *first, *last;
first = orig->flink;
if (first != orig) {
first->blink = dest;
dest->flink = first;
last = orig->blink;
last->flink = dest;
dest->blink = last;
orig->flink = orig;
orig->blink = orig;
} else {
dest->flink = dest;
dest->blink = dest;
}
}
#define sym_que_entry(ptr, type, member) \
((type *)((char *)(ptr)-(unsigned int)(&((type *)0)->member)))
#define sym_insque(new, pos) __sym_que_add(new, pos, (pos)->flink)
#define sym_remque(el) __sym_que_del((el)->blink, (el)->flink)
#define sym_insque_head(new, head) __sym_que_add(new, head, (head)->flink)
static __inline struct sym_quehead *sym_remque_head(struct sym_quehead *head)
{
struct sym_quehead *elem = head->flink;
if (elem != head)
__sym_que_del(head, elem->flink);
else
elem = NULL;
return elem;
}
#define sym_insque_tail(new, head) __sym_que_add(new, (head)->blink, head)
static __inline struct sym_quehead *sym_remque_tail(struct sym_quehead *head)
{
struct sym_quehead *elem = head->blink;
if (elem != head)
__sym_que_del(elem->blink, head);
else
elem = 0;
return elem;
}
/*
* This one may be useful.
*/
#define FOR_EACH_QUEUED_ELEMENT(head, qp) \
for (qp = (head)->flink; qp != (head); qp = qp->flink)
/*
* FreeBSD does not offer our kind of queue in the CAM CCB.
* So, we have to cast.
*/
#define sym_qptr(p) ((struct sym_quehead *) (p))
/*
* Simple bitmap operations.
*/
#define sym_set_bit(p, n) (((u32 *)(p))[(n)>>5] |= (1<<((n)&0x1f)))
#define sym_clr_bit(p, n) (((u32 *)(p))[(n)>>5] &= ~(1<<((n)&0x1f)))
#define sym_is_bit(p, n) (((u32 *)(p))[(n)>>5] & (1<<((n)&0x1f)))
/*
* The below round up/down macros are to be used with a constant
* as argument (sizeof(...) for example), for the compiler to
* optimize the whole thing.
*/
#define _U_(a,m) (a)<=(1<<m)?m:
/*
* Round up logarithm to base 2 of a 16 bit constant.
*/
#define _LGRU16_(a) \
( \
_U_(a, 0)_U_(a, 1)_U_(a, 2)_U_(a, 3)_U_(a, 4)_U_(a, 5)_U_(a, 6)_U_(a, 7) \
_U_(a, 8)_U_(a, 9)_U_(a,10)_U_(a,11)_U_(a,12)_U_(a,13)_U_(a,14)_U_(a,15) \
16)
#endif /* SYM_MISC_H */