Archived
14
0
Fork 0
This repository has been archived on 2022-02-17. You can view files and clone it, but cannot push or open issues or pull requests.
linux-2.6/drivers/s390/scsi/zfcp_qdio.h
Jan Glauber 3ec90878ba [S390] qdio: Split SBAL entry flags
The qdio SBAL entry flag is made-up of four different values that are
independent of one another. Some of the bits are reserved by the
hardware and should not be changed by qdio. Currently all four values
are overwritten since the SBAL entry flag is defined as an u32.

Split the SBAL entry flag into four u8's as defined by the hardware
and don't touch the reserved bits.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-06-06 14:14:56 +02:00

236 lines
6.6 KiB
C

/*
* zfcp device driver
*
* Header file for zfcp qdio interface
*
* Copyright IBM Corporation 2010
*/
#ifndef ZFCP_QDIO_H
#define ZFCP_QDIO_H
#include <asm/qdio.h>
#define ZFCP_QDIO_SBALE_LEN PAGE_SIZE
/* DMQ bug workaround: don't use last SBALE */
#define ZFCP_QDIO_MAX_SBALES_PER_SBAL (QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
/* index of last SBALE (with respect to DMQ bug workaround) */
#define ZFCP_QDIO_LAST_SBALE_PER_SBAL (ZFCP_QDIO_MAX_SBALES_PER_SBAL - 1)
/* Max SBALS for chaining */
#define ZFCP_QDIO_MAX_SBALS_PER_REQ 36
/* max. number of (data buffer) SBALEs in largest SBAL chain
* request ID + QTCB in SBALE 0 + 1 of first SBAL in chain */
#define ZFCP_QDIO_MAX_SBALES_PER_REQ \
(ZFCP_QDIO_MAX_SBALS_PER_REQ * ZFCP_QDIO_MAX_SBALES_PER_SBAL - 2)
/**
* struct zfcp_qdio - basic qdio data structure
* @res_q: response queue
* @req_q: request queue
* @req_q_idx: index of next free buffer
* @req_q_free: number of free buffers in queue
* @stat_lock: lock to protect req_q_util and req_q_time
* @req_q_lock: lock to serialize access to request queue
* @req_q_time: time of last fill level change
* @req_q_util: used for accounting
* @req_q_full: queue full incidents
* @req_q_wq: used to wait for SBAL availability
* @adapter: adapter used in conjunction with this qdio structure
*/
struct zfcp_qdio {
struct qdio_buffer *res_q[QDIO_MAX_BUFFERS_PER_Q];
struct qdio_buffer *req_q[QDIO_MAX_BUFFERS_PER_Q];
u8 req_q_idx;
atomic_t req_q_free;
spinlock_t stat_lock;
spinlock_t req_q_lock;
unsigned long long req_q_time;
u64 req_q_util;
atomic_t req_q_full;
wait_queue_head_t req_q_wq;
struct zfcp_adapter *adapter;
};
/**
* struct zfcp_qdio_req - qdio queue related values for a request
* @sbtype: sbal type flags for sbale 0
* @sbal_number: number of free sbals
* @sbal_first: first sbal for this request
* @sbal_last: last sbal for this request
* @sbal_limit: last possible sbal for this request
* @sbale_curr: current sbale at creation of this request
* @sbal_response: sbal used in interrupt
* @qdio_outb_usage: usage of outbound queue
*/
struct zfcp_qdio_req {
u8 sbtype;
u8 sbal_number;
u8 sbal_first;
u8 sbal_last;
u8 sbal_limit;
u8 sbale_curr;
u8 sbal_response;
u16 qdio_outb_usage;
};
/**
* zfcp_qdio_sbale_req - return pointer to sbale on req_q for a request
* @qdio: pointer to struct zfcp_qdio
* @q_rec: pointer to struct zfcp_qdio_req
* Returns: pointer to qdio_buffer_element (sbale) structure
*/
static inline struct qdio_buffer_element *
zfcp_qdio_sbale_req(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
return &qdio->req_q[q_req->sbal_last]->element[0];
}
/**
* zfcp_qdio_sbale_curr - return current sbale on req_q for a request
* @qdio: pointer to struct zfcp_qdio
* @fsf_req: pointer to struct zfcp_fsf_req
* Returns: pointer to qdio_buffer_element (sbale) structure
*/
static inline struct qdio_buffer_element *
zfcp_qdio_sbale_curr(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
return &qdio->req_q[q_req->sbal_last]->element[q_req->sbale_curr];
}
/**
* zfcp_qdio_req_init - initialize qdio request
* @qdio: request queue where to start putting the request
* @q_req: the qdio request to start
* @req_id: The request id
* @sbtype: type flags to set for all sbals
* @data: First data block
* @len: Length of first data block
*
* This is the start of putting the request into the queue, the last
* step is passing the request to zfcp_qdio_send. The request queue
* lock must be held during the whole process from init to send.
*/
static inline
void zfcp_qdio_req_init(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
unsigned long req_id, u8 sbtype, void *data, u32 len)
{
struct qdio_buffer_element *sbale;
int count = min(atomic_read(&qdio->req_q_free),
ZFCP_QDIO_MAX_SBALS_PER_REQ);
q_req->sbal_first = q_req->sbal_last = qdio->req_q_idx;
q_req->sbal_number = 1;
q_req->sbtype = sbtype;
q_req->sbale_curr = 1;
q_req->sbal_limit = (q_req->sbal_first + count - 1)
% QDIO_MAX_BUFFERS_PER_Q;
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->addr = (void *) req_id;
sbale->eflags = 0;
sbale->sflags = SBAL_SFLAGS0_COMMAND | sbtype;
if (unlikely(!data))
return;
sbale++;
sbale->addr = data;
sbale->length = len;
}
/**
* zfcp_qdio_fill_next - Fill next sbale, only for single sbal requests
* @qdio: pointer to struct zfcp_qdio
* @q_req: pointer to struct zfcp_queue_req
*
* This is only required for single sbal requests, calling it when
* wrapping around to the next sbal is a bug.
*/
static inline
void zfcp_qdio_fill_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
void *data, u32 len)
{
struct qdio_buffer_element *sbale;
BUG_ON(q_req->sbale_curr == ZFCP_QDIO_LAST_SBALE_PER_SBAL);
q_req->sbale_curr++;
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->addr = data;
sbale->length = len;
}
/**
* zfcp_qdio_set_sbale_last - set last entry flag in current sbale
* @qdio: pointer to struct zfcp_qdio
* @q_req: pointer to struct zfcp_queue_req
*/
static inline
void zfcp_qdio_set_sbale_last(struct zfcp_qdio *qdio,
struct zfcp_qdio_req *q_req)
{
struct qdio_buffer_element *sbale;
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;
}
/**
* zfcp_qdio_sg_one_sbal - check if one sbale is enough for sg data
* @sg: The scatterlist where to check the data size
*
* Returns: 1 when one sbale is enough for the data in the scatterlist,
* 0 if not.
*/
static inline
int zfcp_qdio_sg_one_sbale(struct scatterlist *sg)
{
return sg_is_last(sg) && sg->length <= ZFCP_QDIO_SBALE_LEN;
}
/**
* zfcp_qdio_skip_to_last_sbale - skip to last sbale in sbal
* @q_req: The current zfcp_qdio_req
*/
static inline
void zfcp_qdio_skip_to_last_sbale(struct zfcp_qdio_req *q_req)
{
q_req->sbale_curr = ZFCP_QDIO_LAST_SBALE_PER_SBAL;
}
/**
* zfcp_qdio_sbal_limit - set the sbal limit for a request in q_req
* @qdio: pointer to struct zfcp_qdio
* @q_req: The current zfcp_qdio_req
* @max_sbals: maximum number of SBALs allowed
*/
static inline
void zfcp_qdio_sbal_limit(struct zfcp_qdio *qdio,
struct zfcp_qdio_req *q_req, int max_sbals)
{
int count = min(atomic_read(&qdio->req_q_free), max_sbals);
q_req->sbal_limit = (q_req->sbal_first + count - 1) %
QDIO_MAX_BUFFERS_PER_Q;
}
/**
* zfcp_qdio_set_data_div - set data division count
* @qdio: pointer to struct zfcp_qdio
* @q_req: The current zfcp_qdio_req
* @count: The data division count
*/
static inline
void zfcp_qdio_set_data_div(struct zfcp_qdio *qdio,
struct zfcp_qdio_req *q_req, u32 count)
{
struct qdio_buffer_element *sbale;
sbale = &qdio->req_q[q_req->sbal_first]->element[0];
sbale->length = count;
}
#endif /* ZFCP_QDIO_H */