#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;
}
}
#endif /* DEF_RDMAVT_INCMRH */
