/**
* zfcp_qdio_sbal_chain - chain SBALs if more than one SBAL is needed for a
* request
* @fsf_req: zfcp_fsf_req to be processed
* @sbtype: SBAL flags which have to be set in first SBALE of new SBAL
*
* This function changes sbal_curr, sbale_curr, sbal_number of fsf_req.
*/
static inline volatile struct qdio_buffer_element *
zfcp_qdio_sbal_chain(struct zfcp_fsf_req *fsf_req, unsigned long sbtype)
{
volatile struct qdio_buffer_element *sbale;
/* set last entry flag in current SBALE of current SBAL */
sbale = zfcp_qdio_sbale_curr(fsf_req);
sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
/* don't exceed last allowed SBAL */
if (fsf_req->sbal_curr == fsf_req->sbal_last)
return NULL;
/* set chaining flag in first SBALE of current SBAL */
sbale = zfcp_qdio_sbale_req(fsf_req, fsf_req->sbal_curr, 0);
sbale->flags |= SBAL_FLAGS0_MORE_SBALS;
/* calculate index of next SBAL */
fsf_req->sbal_curr++;
fsf_req->sbal_curr %= QDIO_MAX_BUFFERS_PER_Q;
/* keep this requests number of SBALs up-to-date */
fsf_req->sbal_number++;
/* start at first SBALE of new SBAL */
fsf_req->sbale_curr = 0;
/* set storage-block type for new SBAL */
sbale = zfcp_qdio_sbale_curr(fsf_req);
sbale->flags |= sbtype;
return sbale;
}
static struct qdio_buffer_element *
zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
struct qdio_buffer_element *sbale;
/* set last entry flag in current SBALE of current SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;
/* don't exceed last allowed SBAL */
if (q_req->sbal_last == q_req->sbal_limit)
return NULL;
/* set chaining flag in first SBALE of current SBAL */
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS;
/* calculate index of next SBAL */
q_req->sbal_last++;
q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
/* keep this requests number of SBALs up-to-date */
q_req->sbal_number++;
BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);
/* start at first SBALE of new SBAL */
q_req->sbale_curr = 0;
/* set storage-block type for new SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->sflags |= q_req->sbtype;
return sbale;
}
/**
* zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
* @fsf_req: request to be processed
* @sbtype: SBALE flags
* @sg: scatter-gather list
* @max_sbals: upper bound for number of SBALs to be used
* Returns: number of bytes, or error (negativ)
*/
int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio,
struct zfcp_queue_req *q_req,
unsigned long sbtype, struct scatterlist *sg,
int max_sbals)
{
struct qdio_buffer_element *sbale;
int retval, bytes = 0;
/* figure out last allowed SBAL */
zfcp_qdio_sbal_limit(qdio, q_req, max_sbals);
/* set storage-block type for this request */
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->flags |= sbtype;
for (; sg; sg = sg_next(sg)) {
retval = zfcp_qdio_fill_sbals(qdio, q_req, sbtype,
sg_virt(sg), sg->length);
if (retval < 0)
return retval;
bytes += sg->length;
}
/* assume that no other SBALEs are to follow in the same SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
return bytes;
}
static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)
return zfcp_qdio_sbal_chain(qdio, q_req);
q_req->sbale_curr++;
return zfcp_qdio_sbale_curr(qdio, q_req);
}
static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
if (q_req->sbale_curr == ZFCP_QDIO_LAST_SBALE_PER_SBAL)
return zfcp_qdio_sbal_chain(qdio, q_req);
q_req->sbale_curr++;
return zfcp_qdio_sbale_curr(qdio, q_req);
}
static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_fsf_req *fsf_req, unsigned long sbtype)
{
if (fsf_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
return zfcp_qdio_sbal_chain(fsf_req, sbtype);
fsf_req->sbale_curr++;
return zfcp_qdio_sbale_curr(fsf_req);
}
static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_queue_req *q_req,
unsigned int sbtype)
{
if (q_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
return zfcp_qdio_sbal_chain(qdio, q_req, sbtype);
q_req->sbale_curr++;
return zfcp_qdio_sbale_curr(qdio, q_req);
}
/**
* zfcp_qdio_sbale_fill - set address and lenght in current SBALE
* on request_queue
*/
static inline void
zfcp_qdio_sbale_fill(struct zfcp_fsf_req *fsf_req, unsigned long sbtype,
void *addr, int length)
{
volatile struct qdio_buffer_element *sbale;
sbale = zfcp_qdio_sbale_curr(fsf_req);
sbale->addr = addr;
sbale->length = length;
}
/**
* zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
* @fsf_req: request to be processed
* @sbtype: SBALE flags
* @sg: scatter-gather list
* @sg_count: number of elements in scatter-gather list
* @max_sbals: upper bound for number of SBALs to be used
*/
inline int
zfcp_qdio_sbals_from_sg(struct zfcp_fsf_req *fsf_req, unsigned long sbtype,
struct scatterlist *sg, int sg_count, int max_sbals)
{
int sg_index;
struct scatterlist *sg_segment;
int retval;
volatile struct qdio_buffer_element *sbale;
int bytes = 0;
/* figure out last allowed SBAL */
zfcp_qdio_sbal_limit(fsf_req, max_sbals);
/* set storage-block type for current SBAL */
sbale = zfcp_qdio_sbale_req(fsf_req, fsf_req->sbal_curr, 0);
sbale->flags |= sbtype;
/* process all segements of scatter-gather list */
for (sg_index = 0, sg_segment = sg, bytes = 0;
sg_index < sg_count;
sg_index++, sg_segment++) {
retval = zfcp_qdio_sbals_from_segment(
fsf_req,
sbtype,
zfcp_sg_to_address(sg_segment),
sg_segment->length);
if (retval < 0) {
bytes = retval;
goto out;
} else
bytes += retval;
}
/* assume that no other SBALEs are to follow in the same SBAL */
sbale = zfcp_qdio_sbale_curr(fsf_req);
sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
out:
#ifdef ZFCP_STAT_REQSIZES
if (sbtype == SBAL_FLAGS0_TYPE_READ) {
zfcp_statistics_inc(&zfcp_data.read_sguse_head, sg_count);
zfcp_statistics_inc(&zfcp_data.read_req_head, bytes);
} else {
zfcp_statistics_inc(&zfcp_data.write_sguse_head, sg_count);
zfcp_statistics_inc(&zfcp_data.write_req_head, bytes);
}
#endif
return bytes;
}
/**
* zfcp_qdio_sbale_fill - set address and lenght in current SBALE
* on request_queue
*/
static inline void
zfcp_qdio_sbale_fill(struct zfcp_fsf_req *fsf_req, unsigned long sbtype,
void *addr, int length)
{
volatile struct qdio_buffer_element *sbale;
sbale = zfcp_qdio_sbale_curr(fsf_req);
sbale->addr = addr;
sbale->length = length;
#ifdef ZFCP_STAT_REQSIZES
if (sbtype == SBAL_FLAGS0_TYPE_READ)
zfcp_statistics_inc(&zfcp_data.read_sg_head, length);
else zfcp_statistics_inc(&zfcp_data.write_sg_head, length);
#endif
}
/* process all segements of scatter-gather list */
for_each_sg(sgl, sg_segment, sg_count, sg_index) {
retval = zfcp_qdio_sbals_from_segment(
fsf_req,
sbtype,
zfcp_sg_to_address(sg_segment),
sg_segment->length);
if (retval < 0) {
bytes = retval;
goto out;
} else
bytes += retval;
}
/* assume that no other SBALEs are to follow in the same SBAL */
sbale = zfcp_qdio_sbale_curr(fsf_req);
sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
out:
return bytes;
}
/**
* zfcp_qdio_sbals_from_scsicmnd - fill SBALs from scsi command
* @fsf_req: request to be processed
* @sbtype: SBALE flags
* @scsi_cmnd: either scatter-gather list or buffer contained herein is used
* to fill SBALs
*/
int
zfcp_qdio_sbals_from_scsicmnd(struct zfcp_fsf_req *fsf_req,