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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * zfcp device driver4 *5 * Header file for zfcp qdio interface6 *7 * Copyright IBM Corp. 20108 */9 10#ifndef ZFCP_QDIO_H11#define ZFCP_QDIO_H12 13#include <linux/interrupt.h>14#include <asm/qdio.h>15 16#define ZFCP_QDIO_SBALE_LEN PAGE_SIZE17 18/* Max SBALS for chaining */19#define ZFCP_QDIO_MAX_SBALS_PER_REQ 3620 21/**22 * struct zfcp_qdio - basic qdio data structure23 * @res_q: response queue24 * @req_q: request queue25 * @req_q_idx: index of next free buffer26 * @req_q_free: number of free buffers in queue27 * @stat_lock: lock to protect req_q_util and req_q_time28 * @req_q_lock: lock to serialize access to request queue29 * @req_q_time: time of last fill level change30 * @req_q_util: used for accounting31 * @req_q_full: queue full incidents32 * @req_q_wq: used to wait for SBAL availability33 * @irq_tasklet: used for QDIO interrupt processing34 * @request_tasklet: used for Request Queue completion processing35 * @request_timer: used to trigger the Request Queue completion processing36 * @adapter: adapter used in conjunction with this qdio structure37 * @max_sbale_per_sbal: qdio limit per sbal38 * @max_sbale_per_req: qdio limit per request39 */40struct zfcp_qdio {41 struct qdio_buffer *res_q[QDIO_MAX_BUFFERS_PER_Q];42 struct qdio_buffer *req_q[QDIO_MAX_BUFFERS_PER_Q];43 u8 req_q_idx;44 atomic_t req_q_free;45 spinlock_t stat_lock;46 spinlock_t req_q_lock;47 unsigned long long req_q_time;48 u64 req_q_util;49 atomic_t req_q_full;50 wait_queue_head_t req_q_wq;51 struct tasklet_struct irq_tasklet;52 struct tasklet_struct request_tasklet;53 struct timer_list request_timer;54 struct zfcp_adapter *adapter;55 u16 max_sbale_per_sbal;56 u16 max_sbale_per_req;57};58 59/**60 * struct zfcp_qdio_req - qdio queue related values for a request61 * @sbtype: sbal type flags for sbale 062 * @sbal_number: number of free sbals63 * @sbal_first: first sbal for this request64 * @sbal_last: last sbal for this request65 * @sbal_limit: last possible sbal for this request66 * @sbale_curr: current sbale at creation of this request67 * @qdio_outb_usage: usage of outbound queue68 */69struct zfcp_qdio_req {70 u8 sbtype;71 u8 sbal_number;72 u8 sbal_first;73 u8 sbal_last;74 u8 sbal_limit;75 u8 sbale_curr;76 u16 qdio_outb_usage;77};78 79/**80 * zfcp_qdio_sbale_req - return pointer to sbale on req_q for a request81 * @qdio: pointer to struct zfcp_qdio82 * @q_req: pointer to struct zfcp_qdio_req83 * Returns: pointer to qdio_buffer_element (sbale) structure84 */85static inline struct qdio_buffer_element *86zfcp_qdio_sbale_req(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)87{88 return &qdio->req_q[q_req->sbal_last]->element[0];89}90 91/**92 * zfcp_qdio_sbale_curr - return current sbale on req_q for a request93 * @qdio: pointer to struct zfcp_qdio94 * @q_req: pointer to struct zfcp_qdio_req95 * Returns: pointer to qdio_buffer_element (sbale) structure96 */97static inline struct qdio_buffer_element *98zfcp_qdio_sbale_curr(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)99{100 return &qdio->req_q[q_req->sbal_last]->element[q_req->sbale_curr];101}102 103/**104 * zfcp_qdio_req_init - initialize qdio request105 * @qdio: request queue where to start putting the request106 * @q_req: the qdio request to start107 * @req_id: The request id108 * @sbtype: type flags to set for all sbals109 * @data: First data block110 * @len: Length of first data block111 *112 * This is the start of putting the request into the queue, the last113 * step is passing the request to zfcp_qdio_send. The request queue114 * lock must be held during the whole process from init to send.115 */116static inline117void zfcp_qdio_req_init(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,118 u64 req_id, u8 sbtype, void *data, u32 len)119{120 struct qdio_buffer_element *sbale;121 int count = min(atomic_read(&qdio->req_q_free),122 ZFCP_QDIO_MAX_SBALS_PER_REQ);123 124 q_req->sbal_first = q_req->sbal_last = qdio->req_q_idx;125 q_req->sbal_number = 1;126 q_req->sbtype = sbtype;127 q_req->sbale_curr = 1;128 q_req->sbal_limit = (q_req->sbal_first + count - 1)129 % QDIO_MAX_BUFFERS_PER_Q;130 131 sbale = zfcp_qdio_sbale_req(qdio, q_req);132 sbale->addr = u64_to_dma64(req_id);133 sbale->eflags = 0;134 sbale->sflags = SBAL_SFLAGS0_COMMAND | sbtype;135 136 if (unlikely(!data))137 return;138 sbale++;139 sbale->addr = virt_to_dma64(data);140 sbale->length = len;141}142 143/**144 * zfcp_qdio_fill_next - Fill next sbale, only for single sbal requests145 * @qdio: pointer to struct zfcp_qdio146 * @q_req: pointer to struct zfcp_queue_req147 * @data: pointer to data148 * @len: length of data149 *150 * This is only required for single sbal requests, calling it when151 * wrapping around to the next sbal is a bug.152 */153static inline154void zfcp_qdio_fill_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,155 void *data, u32 len)156{157 struct qdio_buffer_element *sbale;158 159 BUG_ON(q_req->sbale_curr == qdio->max_sbale_per_sbal - 1);160 q_req->sbale_curr++;161 sbale = zfcp_qdio_sbale_curr(qdio, q_req);162 sbale->addr = virt_to_dma64(data);163 sbale->length = len;164}165 166/**167 * zfcp_qdio_set_sbale_last - set last entry flag in current sbale168 * @qdio: pointer to struct zfcp_qdio169 * @q_req: pointer to struct zfcp_queue_req170 */171static inline172void zfcp_qdio_set_sbale_last(struct zfcp_qdio *qdio,173 struct zfcp_qdio_req *q_req)174{175 struct qdio_buffer_element *sbale;176 177 sbale = zfcp_qdio_sbale_curr(qdio, q_req);178 sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;179}180 181/**182 * zfcp_qdio_sg_one_sbal - check if one sbale is enough for sg data183 * @sg: The scatterlist where to check the data size184 *185 * Returns: 1 when one sbale is enough for the data in the scatterlist,186 * 0 if not.187 */188static inline189int zfcp_qdio_sg_one_sbale(struct scatterlist *sg)190{191 return sg_is_last(sg) && sg->length <= ZFCP_QDIO_SBALE_LEN;192}193 194/**195 * zfcp_qdio_skip_to_last_sbale - skip to last sbale in sbal196 * @qdio: pointer to struct zfcp_qdio197 * @q_req: The current zfcp_qdio_req198 */199static inline200void zfcp_qdio_skip_to_last_sbale(struct zfcp_qdio *qdio,201 struct zfcp_qdio_req *q_req)202{203 q_req->sbale_curr = qdio->max_sbale_per_sbal - 1;204}205 206/**207 * zfcp_qdio_sbal_limit - set the sbal limit for a request in q_req208 * @qdio: pointer to struct zfcp_qdio209 * @q_req: The current zfcp_qdio_req210 * @max_sbals: maximum number of SBALs allowed211 */212static inline213void zfcp_qdio_sbal_limit(struct zfcp_qdio *qdio,214 struct zfcp_qdio_req *q_req, int max_sbals)215{216 int count = min(atomic_read(&qdio->req_q_free), max_sbals);217 218 q_req->sbal_limit = (q_req->sbal_first + count - 1) %219 QDIO_MAX_BUFFERS_PER_Q;220}221 222/**223 * zfcp_qdio_set_data_div - set data division count224 * @qdio: pointer to struct zfcp_qdio225 * @q_req: The current zfcp_qdio_req226 * @count: The data division count227 */228static inline229void zfcp_qdio_set_data_div(struct zfcp_qdio *qdio,230 struct zfcp_qdio_req *q_req, u32 count)231{232 struct qdio_buffer_element *sbale;233 234 sbale = qdio->req_q[q_req->sbal_first]->element;235 sbale->length = count;236}237 238/**239 * zfcp_qdio_real_bytes - count bytes used240 * @sg: pointer to struct scatterlist241 */242static inline243unsigned int zfcp_qdio_real_bytes(struct scatterlist *sg)244{245 unsigned int real_bytes = 0;246 247 for (; sg; sg = sg_next(sg))248 real_bytes += sg->length;249 250 return real_bytes;251}252 253/**254 * zfcp_qdio_set_scount - set SBAL count value255 * @qdio: pointer to struct zfcp_qdio256 * @q_req: The current zfcp_qdio_req257 */258static inline259void zfcp_qdio_set_scount(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)260{261 struct qdio_buffer_element *sbale;262 263 sbale = qdio->req_q[q_req->sbal_first]->element;264 sbale->scount = q_req->sbal_number - 1;265}266 267#endif /* ZFCP_QDIO_H */268