|  | /* | 
|  | * 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 | 
|  |  | 
|  | /* Max SBALS for chaining */ | 
|  | #define ZFCP_QDIO_MAX_SBALS_PER_REQ	36 | 
|  |  | 
|  | /** | 
|  | * 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; | 
|  | u16			max_sbale_per_sbal; | 
|  | u16			max_sbale_per_req; | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * 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 == qdio->max_sbale_per_sbal - 1); | 
|  | 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 *qdio, | 
|  | struct zfcp_qdio_req *q_req) | 
|  | { | 
|  | q_req->sbale_curr = qdio->max_sbale_per_sbal - 1; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * 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; | 
|  | sbale->length = count; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * zfcp_qdio_sbale_count - count sbale used | 
|  | * @sg: pointer to struct scatterlist | 
|  | */ | 
|  | static inline | 
|  | unsigned int zfcp_qdio_sbale_count(struct scatterlist *sg) | 
|  | { | 
|  | unsigned int count = 0; | 
|  |  | 
|  | for (; sg; sg = sg_next(sg)) | 
|  | count++; | 
|  |  | 
|  | return count; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * zfcp_qdio_real_bytes - count bytes used | 
|  | * @sg: pointer to struct scatterlist | 
|  | */ | 
|  | static inline | 
|  | unsigned int zfcp_qdio_real_bytes(struct scatterlist *sg) | 
|  | { | 
|  | unsigned int real_bytes = 0; | 
|  |  | 
|  | for (; sg; sg = sg_next(sg)) | 
|  | real_bytes += sg->length; | 
|  |  | 
|  | return real_bytes; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * zfcp_qdio_set_scount - set SBAL count value | 
|  | * @qdio: pointer to struct zfcp_qdio | 
|  | * @q_req: The current zfcp_qdio_req | 
|  | */ | 
|  | static inline | 
|  | void zfcp_qdio_set_scount(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) | 
|  | { | 
|  | struct qdio_buffer_element *sbale; | 
|  |  | 
|  | sbale = qdio->req_q[q_req->sbal_first]->element; | 
|  | sbale->scount = q_req->sbal_number - 1; | 
|  | } | 
|  |  | 
|  | #endif /* ZFCP_QDIO_H */ |