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1/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */2/*3 * Copyright(c) 2016 Intel Corporation.4 */5 6#ifndef DEF_RDMAVT_INCMR_H7#define DEF_RDMAVT_INCMR_H8 9/*10 * For Memory Regions. This stuff should probably be moved into rdmavt/mr.h once11 * drivers no longer need access to the MR directly.12 */13#include <linux/percpu-refcount.h>14 15/*16 * A segment is a linear region of low physical memory.17 * Used by the verbs layer.18 */19struct rvt_seg {20	void *vaddr;21	size_t length;22};23 24/* The number of rvt_segs that fit in a page. */25#define RVT_SEGSZ     (PAGE_SIZE / sizeof(struct rvt_seg))26 27struct rvt_segarray {28	struct rvt_seg segs[RVT_SEGSZ];29};30 31struct rvt_mregion {32	struct ib_pd *pd;       /* shares refcnt of ibmr.pd */33	u64 user_base;          /* User's address for this region */34	u64 iova;               /* IB start address of this region */35	size_t length;36	u32 lkey;37	u32 offset;             /* offset (bytes) to start of region */38	int access_flags;39	u32 max_segs;           /* number of rvt_segs in all the arrays */40	u32 mapsz;              /* size of the map array */41	atomic_t lkey_invalid;	/* true if current lkey is invalid */42	u8  page_shift;         /* 0 - non unform/non powerof2 sizes */43	u8  lkey_published;     /* in global table */44	struct percpu_ref refcount;45	struct completion comp; /* complete when refcount goes to zero */46	struct rvt_segarray *map[];    /* the segments */47};48 49#define RVT_MAX_LKEY_TABLE_BITS 2350 51struct rvt_lkey_table {52	/* read mostly fields */53	u32 max;                /* size of the table */54	u32 shift;              /* lkey/rkey shift */55	struct rvt_mregion __rcu **table;56	/* writeable fields */57	/* protect changes in this struct */58	spinlock_t lock ____cacheline_aligned_in_smp;59	u32 next;               /* next unused index (speeds search) */60	u32 gen;                /* generation count */61};62 63/*64 * These keep track of the copy progress within a memory region.65 * Used by the verbs layer.66 */67struct rvt_sge {68	struct rvt_mregion *mr;69	void *vaddr;            /* kernel virtual address of segment */70	u32 sge_length;         /* length of the SGE */71	u32 length;             /* remaining length of the segment */72	u16 m;                  /* current index: mr->map[m] */73	u16 n;                  /* current index: mr->map[m]->segs[n] */74};75 76struct rvt_sge_state {77	struct rvt_sge *sg_list;      /* next SGE to be used if any */78	struct rvt_sge sge;   /* progress state for the current SGE */79	u32 total_len;80	u8 num_sge;81};82 83static inline void rvt_put_mr(struct rvt_mregion *mr)84{85	percpu_ref_put(&mr->refcount);86}87 88static inline void rvt_get_mr(struct rvt_mregion *mr)89{90	percpu_ref_get(&mr->refcount);91}92 93static inline void rvt_put_ss(struct rvt_sge_state *ss)94{95	while (ss->num_sge) {96		rvt_put_mr(ss->sge.mr);97		if (--ss->num_sge)98			ss->sge = *ss->sg_list++;99	}100}101 102static inline u32 rvt_get_sge_length(struct rvt_sge *sge, u32 length)103{104	u32 len = sge->length;105 106	if (len > length)107		len = length;108	if (len > sge->sge_length)109		len = sge->sge_length;110 111	return len;112}113 114static inline void rvt_update_sge(struct rvt_sge_state *ss, u32 length,115				  bool release)116{117	struct rvt_sge *sge = &ss->sge;118 119	sge->vaddr += length;120	sge->length -= length;121	sge->sge_length -= length;122	if (sge->sge_length == 0) {123		if (release)124			rvt_put_mr(sge->mr);125		if (--ss->num_sge)126			*sge = *ss->sg_list++;127	} else if (sge->length == 0 && sge->mr->lkey) {128		if (++sge->n >= RVT_SEGSZ) {129			if (++sge->m >= sge->mr->mapsz)130				return;131			sge->n = 0;132		}133		sge->vaddr = sge->mr->map[sge->m]->segs[sge->n].vaddr;134		sge->length = sge->mr->map[sge->m]->segs[sge->n].length;135	}136}137 138static inline void rvt_skip_sge(struct rvt_sge_state *ss, u32 length,139				bool release)140{141	struct rvt_sge *sge = &ss->sge;142 143	while (length) {144		u32 len = rvt_get_sge_length(sge, length);145 146		WARN_ON_ONCE(len == 0);147		rvt_update_sge(ss, len, release);148		length -= len;149	}150}151 152bool rvt_ss_has_lkey(struct rvt_sge_state *ss, u32 lkey);153bool rvt_mr_has_lkey(struct rvt_mregion *mr, u32 lkey);154 155#endif          /* DEF_RDMAVT_INCMRH */156