/*
* Copyright (c) 2016 HGST, a Western Digital Company.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*/
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/pci-p2pdma.h>
#include <rdma/mr_pool.h>
#include <rdma/rw.h>
enum {
RDMA_RW_SINGLE_WR,
RDMA_RW_MULTI_WR,
RDMA_RW_MR,
RDMA_RW_SIG_MR,
};
static bool rdma_rw_force_mr;
module_param_named(force_mr, rdma_rw_force_mr, bool, 0);
MODULE_PARM_DESC(force_mr, "Force usage of MRs for RDMA READ/WRITE operations");
/*
* Check if the device might use memory registration. This is currently only
* true for iWarp devices. In the future we can hopefully fine tune this based
* on HCA driver input.
*/
static inline bool rdma_rw_can_use_mr(struct ib_device *dev, u8 port_num)
{
if (rdma_protocol_iwarp(dev, port_num))
return true;
if (unlikely(rdma_rw_force_mr))
return true;
return false;
}
/*
* Check if the device will use memory registration for this RW operation.
* We currently always use memory registrations for iWarp RDMA READs, and
* have a debug option to force usage of MRs.
*
* XXX: In the future we can hopefully fine tune this based on HCA driver
* input.
*/
static inline bool rdma_rw_io_needs_mr(struct ib_device *dev, u8 port_num,
enum dma_data_direction dir, int dma_nents)
{
if (rdma_protocol_iwarp(dev, port_num) && dir == DMA_FROM_DEVICE)
return true;
if (unlikely(rdma_rw_force_mr))
return true;
return false;
}
static inline u32 rdma_rw_fr_page_list_len(struct ib_device *dev)
{
/* arbitrary limit to avoid allocating gigantic resources */
return min_t(u32, dev->attrs.max_fast_reg_page_list_len, 256);
}
/* Caller must have zero-initialized *reg. */
static int rdma_rw_init_one_mr(struct ib_qp *qp, u8 port_num,
struct rdma_rw_reg_ctx *reg, struct scatterlist *sg,
u32 sg_cnt, u32 offset)
{
u32 pages_per_mr = rdma_rw_fr_page_list_len(qp->pd->device);
u32 nents = min(sg_cnt, pages_per_mr);
int count = 0, ret;
reg->mr = ib_mr_pool_get(qp, &qp->rdma_mrs);
if (!reg->mr)
return -EAGAIN;
if (reg->mr->need_inval) {
reg->inv_wr.opcode = IB_WR_LOCAL_INV;
reg->inv_wr.ex.invalidate_rkey = reg->mr->lkey;
reg->inv_wr.next = ®->reg_wr.wr;
count++;
} else {
reg->inv_wr.next = NULL;
}
ret = ib_map_mr_sg(reg->mr, sg, nents, &offset, PAGE_SIZE);
if (ret < 0 || ret < nents) {
ib_mr_pool_put(qp, &qp->rdma_mrs, reg->mr);
return -EINVAL;
}
reg->reg_wr.wr.opcode = IB_WR_REG_MR;
reg->reg_wr.mr = reg->mr;
reg->reg_wr.access = IB_ACCESS_LOCAL_WRITE;
if (rdma_protocol_iwarp(qp->device, port_num))
reg->reg_wr.access |= IB_ACCESS_REMOTE_WRITE;
count++;
reg->sge.addr = reg->mr->iova;
reg->sge.length = reg->mr->length;
return count;
}
static int rdma_rw_init_mr_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp,
u8 port_num, struct scatterlist *sg, u32 sg_cnt, u32 offset,
u64 remote_addr, u32 rkey, enum dma_data_direction dir)
{
struct rdma_rw_reg_ctx *prev = NULL;
u32 pages_per_mr = rdma_rw_fr_page_list_len(qp->pd->device);
int i, j, ret = 0, count = 0;
ctx->nr_ops = (sg_cnt + pages_per_mr - 1) / pages_per_mr;
ctx->reg = kcalloc(ctx->nr_ops, sizeof(*ctx->reg), GFP_KERNEL);
if (!ctx->reg) {
ret = -ENOMEM;
goto out;
}
for (i = 0; i < ctx->nr_ops; i++) {
struct rdma_rw_reg_ctx *reg = &ctx->reg[i];
u32 nents = min(sg_cnt, pages_per_mr);
ret = rdma_rw_init_one_mr(qp, port_num, reg, sg, sg_cnt,
offset);
if (ret < 0)
goto out_free;
count += ret;
if (prev) {
if (reg->mr->need_inval)
prev->wr.wr.next = ®->inv_wr;
else
prev->wr.wr.next = ®->reg_wr.wr;
}
reg->reg_wr.wr.next = ®->wr.wr;
reg->wr.wr.sg_list = ®->sge;
reg->wr.wr.num_sge = 1;
reg->wr.remote_addr = remote_addr;
reg->wr.rkey = rkey;
if (dir == DMA_TO_DEVICE) {
reg->wr.wr.opcode = IB_WR_RDMA_WRITE;
} else if (!rdma_cap_read_inv(qp->device, port_num)) {
reg->wr.wr.opcode = IB_WR_RDMA_READ;
} else {
reg->wr.wr.opcode = IB_WR_RDMA_READ_WITH_INV;
reg->wr.wr.ex.invalidate_rkey = reg->mr->lkey;
}
count++;
remote_addr += reg->sge.length;
sg_cnt -= nents;
for (j = 0; j < nents; j++)
sg = sg_next(sg);
prev = reg;
offset = 0;
}
if (prev)
prev->wr.wr.next = NULL;
ctx->type = RDMA_RW_MR;
return count;
out_free:
while (--i >= 0)
ib_mr_pool_put(qp, &qp->rdma_mrs, ctx->reg[i].mr);
kfree(ctx->reg);
out:
return ret;
}
static int rdma_rw_init_map_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp,
struct scatterlist *sg, u32 sg_cnt, u32 offset,
u64 remote_addr, u32 rkey, enum dma_data_direction dir)
{
struct ib_device *dev = qp->pd->device;
u32 max_sge = dir == DMA_TO_DEVICE ? qp->max_write_sge :
qp->max_read_sge;
struct ib_sge *sge;
u32 total_len = 0, i, j;
ctx->nr_ops = DIV_ROUND_UP(sg_cnt, max_sge);
ctx->map.sges = sge = kcalloc(sg_cnt, sizeof(*sge), GFP_KERNEL);
if (!ctx->map.sges)
goto out;
ctx->map.wrs = kcalloc(ctx->nr_ops, sizeof(*ctx->map.wrs), GFP_KERNEL);
if (!ctx->map.wrs)
goto out_free_sges;
for (i = 0; i < ctx->nr_ops; i++) {
struct ib_rdma_wr *rdma_wr = &ctx->map.wrs[i];
u32 nr_sge = min(sg_cnt, max_sge);
if (dir == DMA_TO_DEVICE)
rdma_wr->wr.opcode = IB_WR_RDMA_WRITE;
else
rdma_wr->wr.opcode = IB_WR_RDMA_READ;
rdma_wr->remote_addr = remote_addr + total_len;
rdma_wr->rkey = rkey;
rdma_wr->wr.num_sge = nr_sge;
rdma_wr->wr.sg_list = sge;
for (j = 0; j < nr_sge; j++, sg = sg_next(sg)) {
sge->addr = ib_sg_dma_address(dev, sg) + offset;
sge->length = ib_sg_dma_len(dev, sg) - offset;
sge->lkey = qp->pd->local_dma_lkey;
total_len += sge->length;
sge++;
sg_cnt--;
offset = 0;
}
rdma_wr->wr.next = i + 1 < ctx->nr_ops ?
&ctx->map.wrs[i + 1].wr : NULL;
}
ctx->type = RDMA_RW_MULTI_WR;
return ctx->nr_ops;
out_free_sges:
kfree(ctx->map.sges);
out:
return -ENOMEM;
}
static int rdma_rw_init_single_wr(struct rdma_rw_ctx *ctx, struct ib_qp *qp,
struct scatterlist *sg, u32 offset, u64 remote_addr, u32 rkey,
enum dma_data_direction dir)
{
struct ib_device *dev = qp->pd->device;
struct ib_rdma_wr *rdma_wr = &ctx->single.wr;
ctx->nr_ops = 1;
ctx->single.sge.lkey = qp->pd->local_dma_lkey;
ctx->single.sge.addr = ib_sg_dma_address(dev, sg) + offset;
ctx->single.sge.length = ib_sg_dma_len(dev, sg) - offset;
memset(rdma_wr, 0, sizeof(*rdma_wr));
if (dir == DMA_TO_DEVICE)
rdma_wr->wr.opcode = IB_WR_RDMA_WRITE;
else
rdma_wr->wr.opcode = IB_WR_RDMA_READ;
rdma_wr->wr.sg_list = &ctx->single.sge;
rdma_wr->wr.num_sge = 1;
rdma_wr->remote_addr = remote_addr;
rdma_wr->rkey = rkey;
ctx->type = RDMA_RW_SINGLE_WR;
return 1;
}
/**
* rdma_rw_ctx_init - initialize a RDMA READ/WRITE context
* @ctx: context to initialize
* @qp: queue pair to operate on
* @port_num: port num to which the connection is bound
* @sg: scatterlist to READ/WRITE from/to
* @sg_cnt: number of entries in @sg
* @sg_offset: current byte offset into @sg
* @remote_addr:remote address to read/write (relative to @rkey)
* @rkey: remote key to operate on
* @dir: %DMA_TO_DEVICE for RDMA WRITE, %DMA_FROM_DEVICE for RDMA READ
*
* Returns the number of WQEs that will be needed on the workqueue if
* successful, or a negative error code.
*/
int rdma_rw_ctx_init(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u8 port_num,
struct scatterlist *sg, u32 sg_cnt, u32 sg_offset,
u64 remote_addr, u32 rkey, enum dma_data_direction dir)
{
struct ib_device *dev = qp->pd->device;
int ret;
if (is_pci_p2pdma_page(sg_page(sg)))
ret = pci_p2pdma_map_sg(dev->dma_device, sg, sg_cnt, dir);
else
ret = ib_dma_map_sg(dev, sg, sg_cnt, dir);
if (!ret)
return -ENOMEM;
sg_cnt = ret;
/*
* Skip to the S/G entry that sg_offset falls into:
*/
for (;;) {
u32 len = ib_sg_dma_len(dev, sg);
if (sg_offset < len)
break;
sg = sg_next(sg);
sg_offset -= len;
sg_cnt--;
}
ret = -EIO;
if (WARN_ON_ONCE(sg_cnt == 0))
goto out_unmap_sg;
if (rdma_rw_io_needs_mr(qp->device, port_num, dir, sg_cnt)) {
ret = rdma_rw_init_mr_wrs(ctx, qp, port_num, sg, sg_cnt,
sg_offset, remote_addr, rkey, dir);
} else if (sg_cnt > 1) {
ret = rdma_rw_init_map_wrs(ctx, qp, sg, sg_cnt, sg_offset,
remote_addr, rkey, dir);
} else {
ret = rdma_rw_init_single_wr(ctx, qp, sg, sg_offset,
remote_addr, rkey, dir);
}
if (ret < 0)
goto out_unmap_sg;
return ret;
out_unmap_sg:
ib_dma_unmap_sg(dev, sg, sg_cnt, dir);
return ret;
}
EXPORT_SYMBOL(rdma_rw_ctx_init);
/**
* rdma_rw_ctx_signature_init - initialize a RW context with signature offload
* @ctx: context to initialize
* @qp: queue pair to operate on
* @port_num: port num to which the connection is bound
* @sg: scatterlist to READ/WRITE from/to
* @sg_cnt: number of entries in @sg
* @prot_sg: scatterlist to READ/WRITE protection information from/to
* @prot_sg_cnt: number of entries in @prot_sg
* @sig_attrs: signature offloading algorithms
* @remote_addr:remote address to read/write (relative to @rkey)
* @rkey: remote key to operate on
* @dir: %DMA_TO_DEVICE for RDMA WRITE, %DMA_FROM_DEVICE for RDMA READ
*
* Returns the number of WQEs that will be needed on the workqueue if
* successful, or a negative error code.
*/
int rdma_rw_ctx_signature_init(struct rdma_rw_ctx *ctx, struct ib_qp *qp,
u8 port_num, struct scatterlist *sg, u32 sg_cnt,
struct scatterlist *prot_sg, u32 prot_sg_cnt,
struct ib_sig_attrs *sig_attrs,
u64 remote_addr, u32 rkey, enum dma_data_direction dir)
{
struct ib_device *dev = qp->pd->device;
u32 pages_per_mr = rdma_rw_fr_page_list_len(qp->pd->device);
struct ib_rdma_wr *rdma_wr;
struct ib_send_wr *prev_wr = NULL;
int count = 0, ret;
if (sg_cnt > pages_per_mr || prot_sg_cnt > pages_per_mr) {
pr_err("SG count too large\n");
return -EINVAL;
}
ret = ib_dma_map_sg(dev, sg, sg_cnt, dir);
if (!ret)
return -ENOMEM;
sg_cnt = ret;
ret = ib_dma_map_sg(dev, prot_sg, prot_sg_cnt, dir);
if (!ret) {
ret = -ENOMEM;
goto out_unmap_sg;
}
prot_sg_cnt = ret;
ctx->type = RDMA_RW_SIG_MR;
ctx->nr_ops = 1;
ctx->sig = kcalloc(1, sizeof(*ctx->sig), GFP_KERNEL);
if (!ctx->sig) {
ret = -ENOMEM;
goto out_unmap_prot_sg;
}
ret = rdma_rw_init_one_mr(qp, port_num, &ctx->sig->data, sg, sg_cnt, 0);
if (ret < 0)
goto out_free_ctx;
count += ret;
prev_wr = &ctx->sig->data.reg_wr.wr;
ret = rdma_rw_init_one_mr(qp, port_num, &ctx->sig->prot,
prot_sg, prot_sg_cnt, 0);
if (ret < 0)
goto out_destroy_data_mr;
count += ret;
if (ctx->sig->prot.inv_wr.next)
prev_wr->next = &ctx->sig->prot.inv_wr;
else
prev_wr->next = &ctx->sig->prot.reg_wr.wr;
prev_wr = &ctx->sig->prot.reg_wr.wr;
ctx->sig->sig_mr = ib_mr_pool_get(qp, &qp->sig_mrs);
if (!ctx->sig->sig_mr) {
ret = -EAGAIN;
goto out_destroy_prot_mr;
}
if (ctx->sig->sig_mr->need_inval) {
memset(&ctx->sig->sig_inv_wr, 0, sizeof(ctx->sig->sig_inv_wr));
ctx->sig->sig_inv_wr.opcode = IB_WR_LOCAL_INV;
ctx->sig->sig_inv_wr.ex.invalidate_rkey = ctx->sig->sig_mr->rkey;
prev_wr->next = &ctx->sig->sig_inv_wr;
prev_wr = &ctx->sig->sig_inv_wr;
}
ctx->sig->sig_wr.wr.opcode = IB_WR_REG_SIG_MR;
ctx->sig->sig_wr.wr.wr_cqe = NULL;
ctx->sig->sig_wr.wr.sg_list = &ctx->sig->data.sge;
ctx->sig->sig_wr.wr.num_sge = 1;
ctx->sig->sig_wr.access_flags = IB_ACCESS_LOCAL_WRITE;
ctx->sig->sig_wr.sig_attrs = sig_attrs;
ctx->sig->sig_wr.sig_mr = ctx->sig->sig_mr;
if (prot_sg_cnt)
ctx->sig->sig_wr.prot = &ctx->sig->prot.sge;
prev_wr->next = &ctx->sig->sig_wr.wr;
prev_wr = &ctx->sig->sig_wr.wr;
count++;
ctx->sig->sig_sge.addr = 0;
ctx->sig->sig_sge.length = ctx->sig->data.sge.length;
if (sig_attrs->wire.sig_type != IB_SIG_TYPE_NONE)
ctx->sig->sig_sge.length += ctx->sig->prot.sge.length;
rdma_wr = &ctx->sig->data.wr;
rdma_wr->wr.sg_list = &ctx->sig->sig_sge;
rdma_wr->wr.num_sge = 1;
rdma_wr->remote_addr = remote_addr;
rdma_wr->rkey = rkey;
if (dir == DMA_TO_DEVICE)
rdma_wr->wr.opcode = IB_WR_RDMA_WRITE;
else
rdma_wr->wr.opcode = IB_WR_RDMA_READ;
prev_wr->next = &rdma_wr->wr;
prev_wr = &rdma_wr->wr;
count++;
return count;
out_destroy_prot_mr:
if (prot_sg_cnt)
ib_mr_pool_put(qp, &qp->rdma_mrs, ctx->sig->prot.mr);
out_destroy_data_mr:
ib_mr_pool_put(qp, &qp->rdma_mrs, ctx->sig->data.mr);
out_free_ctx:
kfree(ctx->sig);
out_unmap_prot_sg:
ib_dma_unmap_sg(dev, prot_sg, prot_sg_cnt, dir);
out_unmap_sg:
ib_dma_unmap_sg(dev, sg, sg_cnt, dir);
return ret;
}
EXPORT_SYMBOL(rdma_rw_ctx_signature_init);
/*
* Now that we are going to post the WRs we can update the lkey and need_inval
* state on the MRs. If we were doing this at init time, we would get double
* or missing invalidations if a context was initialized but not actually
* posted.
*/
static void rdma_rw_update_lkey(struct rdma_rw_reg_ctx *reg, bool need_inval)
{
reg->mr->need_inval = need_inval;
ib_update_fast_reg_key(reg->mr, ib_inc_rkey(reg->mr->lkey));
reg->reg_wr.key = reg->mr->lkey;
reg->sge.lkey = reg->mr->lkey;
}
/**
* rdma_rw_ctx_wrs - return chain of WRs for a RDMA READ or WRITE operation
* @ctx: context to operate on
* @qp: queue pair to operate on
* @port_num: port num to which the connection is bound
* @cqe: completion queue entry for the last WR
* @chain_wr: WR to append to the posted chain
*
* Return the WR chain for the set of RDMA READ/WRITE operations described by
* @ctx, as well as any memory registration operations needed. If @chain_wr
* is non-NULL the WR it points to will be appended to the chain of WRs posted.
* If @chain_wr is not set @cqe must be set so that the caller gets a
* completion notification.
*/
struct ib_send_wr *rdma_rw_ctx_wrs(struct rdma_rw_ctx *ctx, struct ib_qp *qp,
u8 port_num, struct ib_cqe *cqe, struct ib_send_wr *chain_wr)
{
struct ib_send_wr *first_wr, *last_wr;
int i;
switch (ctx->type) {
case RDMA_RW_SIG_MR:
rdma_rw_update_lkey(&ctx->sig->data, true);
if (ctx->sig->prot.mr)
rdma_rw_update_lkey(&ctx->sig->prot, true);
ctx->sig->sig_mr->need_inval = true;
ib_update_fast_reg_key(ctx->sig->sig_mr,
ib_inc_rkey(ctx->sig->sig_mr->lkey));
ctx->sig->sig_sge.lkey = ctx->sig->sig_mr->lkey;
if (ctx->sig->data.inv_wr.next)
first_wr = &ctx->sig->data.inv_wr;
else
first_wr = &ctx->sig->data.reg_wr.wr;
last_wr = &ctx->sig->data.wr.wr;
break;
case RDMA_RW_MR:
for (i = 0; i < ctx->nr_ops; i++) {
rdma_rw_update_lkey(&ctx->reg[i],
ctx->reg[i].wr.wr.opcode !=
IB_WR_RDMA_READ_WITH_INV);
}
if (ctx->reg[0].inv_wr.next)
first_wr = &ctx->reg[0].inv_wr;
else
first_wr = &ctx->reg[0].reg_wr.wr;
last_wr = &ctx->reg[ctx->nr_ops - 1].wr.wr;
break;
case RDMA_RW_MULTI_WR:
first_wr = &ctx->map.wrs[0].wr;
last_wr = &ctx->map.wrs[ctx->nr_ops - 1].wr;
break;
case RDMA_RW_SINGLE_WR:
first_wr = &ctx->single.wr.wr;
last_wr = &ctx->single.wr.wr;
break;
default:
BUG();
}
if (chain_wr) {
last_wr->next = chain_wr;
} else {
last_wr->wr_cqe = cqe;
last_wr->send_flags |= IB_SEND_SIGNALED;
}
return first_wr;
}
EXPORT_SYMBOL(rdma_rw_ctx_wrs);
/**
* rdma_rw_ctx_post - post a RDMA READ or RDMA WRITE operation
* @ctx: context to operate on
* @qp: queue pair to operate on
* @port_num: port num to which the connection is bound
* @cqe: completion queue entry for the last WR
* @chain_wr: WR to append to the posted chain
*
* Post the set of RDMA READ/WRITE operations described by @ctx, as well as
* any memory registration operations needed. If @chain_wr is non-NULL the
* WR it points to will be appended to the chain of WRs posted. If @chain_wr
* is not set @cqe must be set so that the caller gets a completion
* notification.
*/
int rdma_rw_ctx_post(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u8 port_num,
struct ib_cqe *cqe, struct ib_send_wr *chain_wr)
{
struct ib_send_wr *first_wr;
first_wr = rdma_rw_ctx_wrs(ctx, qp, port_num, cqe, chain_wr);
return ib_post_send(qp, first_wr, NULL);
}
EXPORT_SYMBOL(rdma_rw_ctx_post);
/**
* rdma_rw_ctx_destroy - release all resources allocated by rdma_rw_ctx_init
* @ctx: context to release
* @qp: queue pair to operate on
* @port_num: port num to which the connection is bound
* @sg: scatterlist that was used for the READ/WRITE
* @sg_cnt: number of entries in @sg
* @dir: %DMA_TO_DEVICE for RDMA WRITE, %DMA_FROM_DEVICE for RDMA READ
*/
void rdma_rw_ctx_destroy(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u8 port_num,
struct scatterlist *sg, u32 sg_cnt, enum dma_data_direction dir)
{
int i;
switch (ctx->type) {
case RDMA_RW_MR:
for (i = 0; i < ctx->nr_ops; i++)
ib_mr_pool_put(qp, &qp->rdma_mrs, ctx->reg[i].mr);
kfree(ctx->reg);
break;
case RDMA_RW_MULTI_WR:
kfree(ctx->map.wrs);
kfree(ctx->map.sges);
break;
case RDMA_RW_SINGLE_WR:
break;
default:
BUG();
break;
}
/* P2PDMA contexts do not need to be unmapped */
if (!is_pci_p2pdma_page(sg_page(sg)))
ib_dma_unmap_sg(qp->pd->device, sg, sg_cnt, dir);
}
EXPORT_SYMBOL(rdma_rw_ctx_destroy);
/**
* rdma_rw_ctx_destroy_signature - release all resources allocated by
* rdma_rw_ctx_init_signature
* @ctx: context to release
* @qp: queue pair to operate on
* @port_num: port num to which the connection is bound
* @sg: scatterlist that was used for the READ/WRITE
* @sg_cnt: number of entries in @sg
* @prot_sg: scatterlist that was used for the READ/WRITE of the PI
* @prot_sg_cnt: number of entries in @prot_sg
* @dir: %DMA_TO_DEVICE for RDMA WRITE, %DMA_FROM_DEVICE for RDMA READ
*/
void rdma_rw_ctx_destroy_signature(struct rdma_rw_ctx *ctx, struct ib_qp *qp,
u8 port_num, struct scatterlist *sg, u32 sg_cnt,
struct scatterlist *prot_sg, u32 prot_sg_cnt,
enum dma_data_direction dir)
{
if (WARN_ON_ONCE(ctx->type != RDMA_RW_SIG_MR))
return;
ib_mr_pool_put(qp, &qp->rdma_mrs, ctx->sig->data.mr);
ib_dma_unmap_sg(qp->pd->device, sg, sg_cnt, dir);
if (ctx->sig->prot.mr) {
ib_mr_pool_put(qp, &qp->rdma_mrs, ctx->sig->prot.mr);
ib_dma_unmap_sg(qp->pd->device, prot_sg, prot_sg_cnt, dir);
}
ib_mr_pool_put(qp, &qp->sig_mrs, ctx->sig->sig_mr);
kfree(ctx->sig);
}
EXPORT_SYMBOL(rdma_rw_ctx_destroy_signature);
/**
* rdma_rw_mr_factor - return number of MRs required for a payload
* @device: device handling the connection
* @port_num: port num to which the connection is bound
* @maxpages: maximum payload pages per rdma_rw_ctx
*
* Returns the number of MRs the device requires to move @maxpayload
* bytes. The returned value is used during transport creation to
* compute max_rdma_ctxts and the size of the transport's Send and
* Send Completion Queues.
*/
unsigned int rdma_rw_mr_factor(struct ib_device *device, u8 port_num,
unsigned int maxpages)
{
unsigned int mr_pages;
if (rdma_rw_can_use_mr(device, port_num))
mr_pages = rdma_rw_fr_page_list_len(device);
else
mr_pages = device->attrs.max_sge_rd;
return DIV_ROUND_UP(maxpages, mr_pages);
}
EXPORT_SYMBOL(rdma_rw_mr_factor);
void rdma_rw_init_qp(struct ib_device *dev, struct ib_qp_init_attr *attr)
{
u32 factor;
WARN_ON_ONCE(attr->port_num == 0);
/*
* Each context needs at least one RDMA READ or WRITE WR.
*
* For some hardware we might need more, eventually we should ask the
* HCA driver for a multiplier here.
*/
factor = 1;
/*
* If the devices needs MRs to perform RDMA READ or WRITE operations,
* we'll need two additional MRs for the registrations and the
* invalidation.
*/
if (attr->create_flags & IB_QP_CREATE_SIGNATURE_EN)
factor += 6; /* (inv + reg) * (data + prot + sig) */
else if (rdma_rw_can_use_mr(dev, attr->port_num))
factor += 2; /* inv + reg */
attr->cap.max_send_wr += factor * attr->cap.max_rdma_ctxs;
/*
* But maybe we were just too high in the sky and the device doesn't
* even support all we need, and we'll have to live with what we get..
*/
attr->cap.max_send_wr =
min_t(u32, attr->cap.max_send_wr, dev->attrs.max_qp_wr);
}
int rdma_rw_init_mrs(struct ib_qp *qp, struct ib_qp_init_attr *attr)
{
struct ib_device *dev = qp->pd->device;
u32 nr_mrs = 0, nr_sig_mrs = 0;
int ret = 0;
if (attr->create_flags & IB_QP_CREATE_SIGNATURE_EN) {
nr_sig_mrs = attr->cap.max_rdma_ctxs;
nr_mrs = attr->cap.max_rdma_ctxs * 2;
} else if (rdma_rw_can_use_mr(dev, attr->port_num)) {
nr_mrs = attr->cap.max_rdma_ctxs;
}
if (nr_mrs) {
ret = ib_mr_pool_init(qp, &qp->rdma_mrs, nr_mrs,
IB_MR_TYPE_MEM_REG,
rdma_rw_fr_page_list_len(dev));
if (ret) {
pr_err("%s: failed to allocated %d MRs\n",
__func__, nr_mrs);
return ret;
}
}
if (nr_sig_mrs) {
ret = ib_mr_pool_init(qp, &qp->sig_mrs, nr_sig_mrs,
IB_MR_TYPE_SIGNATURE, 2);
if (ret) {
pr_err("%s: failed to allocated %d SIG MRs\n",
__func__, nr_mrs);
goto out_free_rdma_mrs;
}
}
return 0;
out_free_rdma_mrs:
ib_mr_pool_destroy(qp, &qp->rdma_mrs);
return ret;
}
void rdma_rw_cleanup_mrs(struct ib_qp *qp)
{
ib_mr_pool_destroy(qp, &qp->sig_mrs);
ib_mr_pool_destroy(qp, &qp->rdma_mrs);
}
