linux/drivers/infiniband/sw/siw/siw_mem.c

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause

/* Authors: Bernard Metzler <[email protected]> */
/* Copyright (c) 2008-2019, IBM Corporation */

#include <linux/gfp.h>
#include <rdma/ib_verbs.h>
#include <rdma/ib_umem.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/sched/mm.h>
#include <linux/resource.h>

#include "siw.h"
#include "siw_mem.h"

/* Stag lookup is based on its index part only (24 bits). */
#define SIW_STAG_MAX_INDEX …

/*
 * The code avoids special Stag of zero and tries to randomize
 * STag values between 1 and SIW_STAG_MAX_INDEX.
 */
int siw_mem_add(struct siw_device *sdev, struct siw_mem *m)
{ … }

/*
 * siw_mem_id2obj()
 *
 * resolves memory from stag given by id. might be called from:
 * o process context before sending out of sgl, or
 * o in softirq when resolving target memory
 */
struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index)
{ … }

void siw_umem_release(struct siw_umem *umem)
{ … }

int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj,
		   u64 start, u64 len, int rights)
{ … }

void siw_mr_drop_mem(struct siw_mr *mr)
{ … }

void siw_free_mem(struct kref *ref)
{ … }

/*
 * siw_check_mem()
 *
 * Check protection domain, STAG state, access permissions and
 * address range for memory object.
 *
 * @pd:		Protection Domain memory should belong to
 * @mem:	memory to be checked
 * @addr:	starting addr of mem
 * @perms:	requested access permissions
 * @len:	len of memory interval to be checked
 *
 */
int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
		  enum ib_access_flags perms, int len)
{ … }

/*
 * siw_check_sge()
 *
 * Check SGE for access rights in given interval
 *
 * @pd:		Protection Domain memory should belong to
 * @sge:	SGE to be checked
 * @mem:	location of memory reference within array
 * @perms:	requested access permissions
 * @off:	starting offset in SGE
 * @len:	len of memory interval to be checked
 *
 * NOTE: Function references SGE's memory object (mem->obj)
 * if not yet done. New reference is kept if check went ok and
 * released if check failed. If mem->obj is already valid, no new
 * lookup is being done and mem is not released it check fails.
 */
int siw_check_sge(struct ib_pd *pd, struct siw_sge *sge, struct siw_mem *mem[],
		  enum ib_access_flags perms, u32 off, int len)
{ … }

void siw_wqe_put_mem(struct siw_wqe *wqe, enum siw_opcode op)
{ … }

int siw_invalidate_stag(struct ib_pd *pd, u32 stag)
{ … }

/*
 * Gets physical address backed by PBL element. Address is referenced
 * by linear byte offset into list of variably sized PB elements.
 * Optionally, provides remaining len within current element, and
 * current PBL index for later resume at same element.
 */
dma_addr_t siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx)
{ … }

struct siw_pbl *siw_pbl_alloc(u32 num_buf)
{ … }

struct siw_umem *siw_umem_get(struct ib_device *base_dev, u64 start,
			      u64 len, int rights)
{ … }