[mirror_ubuntu-bionic-kernel.git] / include / rdma / rdmavt_mr.h

#ifndef DEF_RDMAVT_INCMR_H
#define DEF_RDMAVT_INCMR_H

/*
 * Copyright(c) 2016 Intel Corporation.
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * BSD LICENSE
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  - Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  - Neither the name of Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/*
 * For Memory Regions. This stuff should probably be moved into rdmavt/mr.h once
 * drivers no longer need access to the MR directly.
 */
#include <linux/percpu-refcount.h>

/*
 * A segment is a linear region of low physical memory.
 * Used by the verbs layer.
 */
struct rvt_seg {
	void *vaddr;
	size_t length;
};

/* The number of rvt_segs that fit in a page. */
#define RVT_SEGSZ     (PAGE_SIZE / sizeof(struct rvt_seg))

struct rvt_segarray {
	struct rvt_seg segs[RVT_SEGSZ];
};

struct rvt_mregion {
	struct ib_pd *pd;       /* shares refcnt of ibmr.pd */
	u64 user_base;          /* User's address for this region */
	u64 iova;               /* IB start address of this region */
	size_t length;
	u32 lkey;
	u32 offset;             /* offset (bytes) to start of region */
	int access_flags;
	u32 max_segs;           /* number of rvt_segs in all the arrays */
	u32 mapsz;              /* size of the map array */
	atomic_t lkey_invalid;	/* true if current lkey is invalid */
	u8  page_shift;         /* 0 - non unform/non powerof2 sizes */
	u8  lkey_published;     /* in global table */
	struct percpu_ref refcount;
	struct completion comp; /* complete when refcount goes to zero */
	struct rvt_segarray *map[0];    /* the segments */
};

#define RVT_MAX_LKEY_TABLE_BITS 23

struct rvt_lkey_table {
	/* read mostly fields */
	u32 max;                /* size of the table */
	u32 shift;              /* lkey/rkey shift */
	struct rvt_mregion __rcu **table;
	/* writeable fields */
	/* protect changes in this struct */
	spinlock_t lock ____cacheline_aligned_in_smp;
	u32 next;               /* next unused index (speeds search) */
	u32 gen;                /* generation count */
};

/*
 * These keep track of the copy progress within a memory region.
 * Used by the verbs layer.
 */
struct rvt_sge {
	struct rvt_mregion *mr;
	void *vaddr;            /* kernel virtual address of segment */
	u32 sge_length;         /* length of the SGE */
	u32 length;             /* remaining length of the segment */
	u16 m;                  /* current index: mr->map[m] */
	u16 n;                  /* current index: mr->map[m]->segs[n] */
};

struct rvt_sge_state {
	struct rvt_sge *sg_list;      /* next SGE to be used if any */
	struct rvt_sge sge;   /* progress state for the current SGE */
	u32 total_len;
	u8 num_sge;
};

static inline void rvt_put_mr(struct rvt_mregion *mr)
{
	percpu_ref_put(&mr->refcount);
}

static inline void rvt_get_mr(struct rvt_mregion *mr)
{
	percpu_ref_get(&mr->refcount);
}

static inline void rvt_put_ss(struct rvt_sge_state *ss)
{
	while (ss->num_sge) {
		rvt_put_mr(ss->sge.mr);
		if (--ss->num_sge)
			ss->sge = *ss->sg_list++;
	}
}

static inline u32 rvt_get_sge_length(struct rvt_sge *sge, u32 length)
{
	u32 len = sge->length;

	if (len > length)
		len = length;
	if (len > sge->sge_length)
		len = sge->sge_length;

	return len;
}

static inline void rvt_update_sge(struct rvt_sge_state *ss, u32 length,
				  bool release)
{
	struct rvt_sge *sge = &ss->sge;

	sge->vaddr += length;
	sge->length -= length;
	sge->sge_length -= length;
	if (sge->sge_length == 0) {
		if (release)
			rvt_put_mr(sge->mr);
		if (--ss->num_sge)
			*sge = *ss->sg_list++;
	} else if (sge->length == 0 && sge->mr->lkey) {
		if (++sge->n >= RVT_SEGSZ) {
			if (++sge->m >= sge->mr->mapsz)
				return;
			sge->n = 0;
		}
		sge->vaddr = sge->mr->map[sge->m]->segs[sge->n].vaddr;
		sge->length = sge->mr->map[sge->m]->segs[sge->n].length;
	}
}

static inline void rvt_skip_sge(struct rvt_sge_state *ss, u32 length,
				bool release)
{
	struct rvt_sge *sge = &ss->sge;

	while (length) {
		u32 len = rvt_get_sge_length(sge, length);

		WARN_ON_ONCE(len == 0);
		rvt_update_sge(ss, len, release);
		length -= len;
	}
}

bool rvt_ss_has_lkey(struct rvt_sge_state *ss, u32 lkey);
bool rvt_mr_has_lkey(struct rvt_mregion *mr, u32 lkey);

#endif          /* DEF_RDMAVT_INCMRH */
Commit	Line	Data
b4e64397 DD	1	#ifndef DEF_RDMAVT_INCMR_H
	2	#define DEF_RDMAVT_INCMR_H
	3
	4	/*
fe314195	5	* Copyright(c) 2016 Intel Corporation.
b4e64397 DD	6	*
	7	* This file is provided under a dual BSD/GPLv2 license. When using or
	8	* redistributing this file, you may do so under either license.
	9	*
	10	* GPL LICENSE SUMMARY
	11	*
	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of version 2 of the GNU General Public License as
	14	* published by the Free Software Foundation.
	15	*
	16	* This program is distributed in the hope that it will be useful, but
	17	* WITHOUT ANY WARRANTY; without even the implied warranty of
	18	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	19	* General Public License for more details.
	20	*
	21	* BSD LICENSE
	22	*
	23	* Redistribution and use in source and binary forms, with or without
	24	* modification, are permitted provided that the following conditions
	25	* are met:
	26	*
	27	* - Redistributions of source code must retain the above copyright
	28	* notice, this list of conditions and the following disclaimer.
	29	* - Redistributions in binary form must reproduce the above copyright
	30	* notice, this list of conditions and the following disclaimer in
	31	* the documentation and/or other materials provided with the
	32	* distribution.
	33	* - Neither the name of Intel Corporation nor the names of its
	34	* contributors may be used to endorse or promote products derived
	35	* from this software without specific prior written permission.
	36	*
	37	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	38	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	39	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	40	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	41	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	42	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	43	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	44	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	45	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	46	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	47	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	48	*
	49	*/
	50
	51	/*
	52	* For Memory Regions. This stuff should probably be moved into rdmavt/mr.h once
	53	* drivers no longer need access to the MR directly.
	54	*/
338adfdd	55	#include <linux/percpu-refcount.h>
b4e64397 DD	56
	57	/*
	58	* A segment is a linear region of low physical memory.
	59	* Used by the verbs layer.
	60	*/
	61	struct rvt_seg {
	62	void *vaddr;
	63	size_t length;
	64	};
	65
	66	/* The number of rvt_segs that fit in a page. */
	67	#define RVT_SEGSZ (PAGE_SIZE / sizeof(struct rvt_seg))
	68
	69	struct rvt_segarray {
	70	struct rvt_seg segs[RVT_SEGSZ];
	71	};
	72
	73	struct rvt_mregion {
	74	struct ib_pd pd; / shares refcnt of ibmr.pd */
	75	u64 user_base; /* User's address for this region */
	76	u64 iova; /* IB start address of this region */
	77	size_t length;
	78	u32 lkey;
	79	u32 offset; /* offset (bytes) to start of region */
	80	int access_flags;
	81	u32 max_segs; /* number of rvt_segs in all the arrays */
	82	u32 mapsz; /* size of the map array */
338adfdd	83	atomic_t lkey_invalid; /* true if current lkey is invalid */
b4e64397 DD	84	u8 page_shift; /* 0 - non unform/non powerof2 sizes */
b4e64397 DD	85	u8 lkey_published; /* in global table */
338adfdd	86	struct percpu_ref refcount;
b4e64397	87	struct completion comp; /* complete when refcount goes to zero */
b4e64397 DD	88	struct rvt_segarray map[0]; / the segments */
	89	};
	90
	91	#define RVT_MAX_LKEY_TABLE_BITS 23
	92
	93	struct rvt_lkey_table {
99f80d2f	94	/* read mostly fields */
b4e64397	95	u32 max; /* size of the table */
99f80d2f	96	u32 shift; /* lkey/rkey shift */
b4e64397	97	struct rvt_mregion __rcu **table;
99f80d2f MM	98	/* writeable fields */
	99	/* protect changes in this struct */
	100	spinlock_t lock ____cacheline_aligned_in_smp;
	101	u32 next; /* next unused index (speeds search) */
	102	u32 gen; /* generation count */
b4e64397 DD	103	};
	104
	105	/*
	106	* These keep track of the copy progress within a memory region.
	107	* Used by the verbs layer.
	108	*/
	109	struct rvt_sge {
	110	struct rvt_mregion *mr;
	111	void vaddr; / kernel virtual address of segment */
	112	u32 sge_length; /* length of the SGE */
	113	u32 length; /* remaining length of the segment */
	114	u16 m; /* current index: mr->map[m] */
	115	u16 n; /* current index: mr->map[m]->segs[n] */
	116	};
	117
	118	struct rvt_sge_state {
	119	struct rvt_sge sg_list; / next SGE to be used if any */
	120	struct rvt_sge sge; /* progress state for the current SGE */
	121	u32 total_len;
	122	u8 num_sge;
	123	};
	124
	125	static inline void rvt_put_mr(struct rvt_mregion *mr)
	126	{
338adfdd	127	percpu_ref_put(&mr->refcount);
b4e64397 DD	128	}
	129
	130	static inline void rvt_get_mr(struct rvt_mregion *mr)
	131	{
338adfdd	132	percpu_ref_get(&mr->refcount);
b4e64397 DD	133	}
b4e64397 DD	134
3b0b3fb3 DD	135	static inline void rvt_put_ss(struct rvt_sge_state *ss)
	136	{
	137	while (ss->num_sge) {
	138	rvt_put_mr(ss->sge.mr);
	139	if (--ss->num_sge)
	140	ss->sge = *ss->sg_list++;
	141	}
	142	}
	143
1198fcea BW	144	static inline u32 rvt_get_sge_length(struct rvt_sge *sge, u32 length)
	145	{
	146	u32 len = sge->length;
	147
	148	if (len > length)
	149	len = length;
	150	if (len > sge->sge_length)
	151	len = sge->sge_length;
	152
	153	return len;
	154	}
	155
	156	static inline void rvt_update_sge(struct rvt_sge_state *ss, u32 length,
	157	bool release)
	158	{
	159	struct rvt_sge *sge = &ss->sge;
	160
	161	sge->vaddr += length;
	162	sge->length -= length;
	163	sge->sge_length -= length;
	164	if (sge->sge_length == 0) {
	165	if (release)
	166	rvt_put_mr(sge->mr);
	167	if (--ss->num_sge)
	168	sge = ss->sg_list++;
	169	} else if (sge->length == 0 && sge->mr->lkey) {
	170	if (++sge->n >= RVT_SEGSZ) {
	171	if (++sge->m >= sge->mr->mapsz)
	172	return;
	173	sge->n = 0;
	174	}
	175	sge->vaddr = sge->mr->map[sge->m]->segs[sge->n].vaddr;
	176	sge->length = sge->mr->map[sge->m]->segs[sge->n].length;
	177	}
	178	}
	179
	180	static inline void rvt_skip_sge(struct rvt_sge_state *ss, u32 length,
	181	bool release)
	182	{
	183	struct rvt_sge *sge = &ss->sge;
	184
	185	while (length) {
	186	u32 len = rvt_get_sge_length(sge, length);
	187
	188	WARN_ON_ONCE(len == 0);
	189	rvt_update_sge(ss, len, release);
	190	length -= len;
	191	}
	192	}
	193
0208da90 MM	194	bool rvt_ss_has_lkey(struct rvt_sge_state *ss, u32 lkey);
	195	bool rvt_mr_has_lkey(struct rvt_mregion *mr, u32 lkey);
	196
b4e64397	197	#endif /* DEF_RDMAVT_INCMRH */