linux-stable/drivers/infiniband/hw/mlx5/mem.c
Yishai Hadas 1f3db16188 IB/mlx5: Generally use the WC auto detection test result
Now that we have direct and reliable detection of WC support by the
system, use is broadly. The only case we have to worry about is when the
WC autodetector cannot run.

For this fringe case generally assume that that WC is available, except in
the well defined case of no PAT support on x86 which is tested by calling
arch_can_pci_mmap_wc().

If WC is wrongly assumed to be available then it causes a small
performance hit on paths in userspace that are tuned to the assumption
that WC is available. There is no functional loss.

It is very unlikely that any platforms exist that lack WC and also care
about the micro optimization of WC in the fringe case where autodetection
does not work.

By removing the fairly bogus CONFIG tests this makes WC work broadly on
all arches and all platforms.

Link: https://lore.kernel.org/r/20200318100323.46659-1-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-03-24 20:22:21 -03:00

392 lines
9.6 KiB
C

/*
* Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* 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.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/module.h>
#include <rdma/ib_umem.h>
#include <rdma/ib_umem_odp.h>
#include "mlx5_ib.h"
#include <linux/jiffies.h>
/* @umem: umem object to scan
* @addr: ib virtual address requested by the user
* @max_page_shift: high limit for page_shift - 0 means no limit
* @count: number of PAGE_SIZE pages covered by umem
* @shift: page shift for the compound pages found in the region
* @ncont: number of compund pages
* @order: log2 of the number of compound pages
*/
void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr,
unsigned long max_page_shift,
int *count, int *shift,
int *ncont, int *order)
{
unsigned long tmp;
unsigned long m;
u64 base = ~0, p = 0;
u64 len, pfn;
int i = 0;
struct scatterlist *sg;
int entry;
addr = addr >> PAGE_SHIFT;
tmp = (unsigned long)addr;
m = find_first_bit(&tmp, BITS_PER_LONG);
if (max_page_shift)
m = min_t(unsigned long, max_page_shift - PAGE_SHIFT, m);
for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
len = sg_dma_len(sg) >> PAGE_SHIFT;
pfn = sg_dma_address(sg) >> PAGE_SHIFT;
if (base + p != pfn) {
/* If either the offset or the new
* base are unaligned update m
*/
tmp = (unsigned long)(pfn | p);
if (!IS_ALIGNED(tmp, 1 << m))
m = find_first_bit(&tmp, BITS_PER_LONG);
base = pfn;
p = 0;
}
p += len;
i += len;
}
if (i) {
m = min_t(unsigned long, ilog2(roundup_pow_of_two(i)), m);
if (order)
*order = ilog2(roundup_pow_of_two(i) >> m);
*ncont = DIV_ROUND_UP(i, (1 << m));
} else {
m = 0;
if (order)
*order = 0;
*ncont = 0;
}
*shift = PAGE_SHIFT + m;
*count = i;
}
/*
* Populate the given array with bus addresses from the umem.
*
* dev - mlx5_ib device
* umem - umem to use to fill the pages
* page_shift - determines the page size used in the resulting array
* offset - offset into the umem to start from,
* only implemented for ODP umems
* num_pages - total number of pages to fill
* pas - bus addresses array to fill
* access_flags - access flags to set on all present pages.
use enum mlx5_ib_mtt_access_flags for this.
*/
void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
int page_shift, size_t offset, size_t num_pages,
__be64 *pas, int access_flags)
{
int shift = page_shift - PAGE_SHIFT;
int mask = (1 << shift) - 1;
int i, k, idx;
u64 cur = 0;
u64 base;
int len;
struct scatterlist *sg;
int entry;
i = 0;
for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
len = sg_dma_len(sg) >> PAGE_SHIFT;
base = sg_dma_address(sg);
/* Skip elements below offset */
if (i + len < offset << shift) {
i += len;
continue;
}
/* Skip pages below offset */
if (i < offset << shift) {
k = (offset << shift) - i;
i = offset << shift;
} else {
k = 0;
}
for (; k < len; k++) {
if (!(i & mask)) {
cur = base + (k << PAGE_SHIFT);
cur |= access_flags;
idx = (i >> shift) - offset;
pas[idx] = cpu_to_be64(cur);
mlx5_ib_dbg(dev, "pas[%d] 0x%llx\n",
i >> shift, be64_to_cpu(pas[idx]));
}
i++;
/* Stop after num_pages reached */
if (i >> shift >= offset + num_pages)
return;
}
}
}
void mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
int page_shift, __be64 *pas, int access_flags)
{
return __mlx5_ib_populate_pas(dev, umem, page_shift, 0,
ib_umem_num_pages(umem), pas,
access_flags);
}
int mlx5_ib_get_buf_offset(u64 addr, int page_shift, u32 *offset)
{
u64 page_size;
u64 page_mask;
u64 off_size;
u64 off_mask;
u64 buf_off;
page_size = (u64)1 << page_shift;
page_mask = page_size - 1;
buf_off = addr & page_mask;
off_size = page_size >> 6;
off_mask = off_size - 1;
if (buf_off & off_mask)
return -EINVAL;
*offset = buf_off >> ilog2(off_size);
return 0;
}
#define WR_ID_BF 0xBF
#define WR_ID_END 0xBAD
#define TEST_WC_NUM_WQES 255
#define TEST_WC_POLLING_MAX_TIME_JIFFIES msecs_to_jiffies(100)
static int post_send_nop(struct mlx5_ib_dev *dev, struct ib_qp *ibqp, u64 wr_id,
bool signaled)
{
struct mlx5_ib_qp *qp = to_mqp(ibqp);
struct mlx5_wqe_ctrl_seg *ctrl;
struct mlx5_bf *bf = &qp->bf;
__be32 mmio_wqe[16] = {};
unsigned long flags;
unsigned int idx;
int i;
if (unlikely(dev->mdev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR))
return -EIO;
spin_lock_irqsave(&qp->sq.lock, flags);
idx = qp->sq.cur_post & (qp->sq.wqe_cnt - 1);
ctrl = mlx5_frag_buf_get_wqe(&qp->sq.fbc, idx);
memset(ctrl, 0, sizeof(struct mlx5_wqe_ctrl_seg));
ctrl->fm_ce_se = signaled ? MLX5_WQE_CTRL_CQ_UPDATE : 0;
ctrl->opmod_idx_opcode =
cpu_to_be32(((u32)(qp->sq.cur_post) << 8) | MLX5_OPCODE_NOP);
ctrl->qpn_ds = cpu_to_be32((sizeof(struct mlx5_wqe_ctrl_seg) / 16) |
(qp->trans_qp.base.mqp.qpn << 8));
qp->sq.wrid[idx] = wr_id;
qp->sq.w_list[idx].opcode = MLX5_OPCODE_NOP;
qp->sq.wqe_head[idx] = qp->sq.head + 1;
qp->sq.cur_post += DIV_ROUND_UP(sizeof(struct mlx5_wqe_ctrl_seg),
MLX5_SEND_WQE_BB);
qp->sq.w_list[idx].next = qp->sq.cur_post;
qp->sq.head++;
memcpy(mmio_wqe, ctrl, sizeof(*ctrl));
((struct mlx5_wqe_ctrl_seg *)&mmio_wqe)->fm_ce_se |=
MLX5_WQE_CTRL_CQ_UPDATE;
/* Make sure that descriptors are written before
* updating doorbell record and ringing the doorbell
*/
wmb();
qp->db.db[MLX5_SND_DBR] = cpu_to_be32(qp->sq.cur_post);
/* Make sure doorbell record is visible to the HCA before
* we hit doorbell
*/
wmb();
for (i = 0; i < 8; i++)
mlx5_write64(&mmio_wqe[i * 2],
bf->bfreg->map + bf->offset + i * 8);
bf->offset ^= bf->buf_size;
spin_unlock_irqrestore(&qp->sq.lock, flags);
return 0;
}
static int test_wc_poll_cq_result(struct mlx5_ib_dev *dev, struct ib_cq *cq)
{
int ret;
struct ib_wc wc = {};
unsigned long end = jiffies + TEST_WC_POLLING_MAX_TIME_JIFFIES;
do {
ret = ib_poll_cq(cq, 1, &wc);
if (ret < 0 || wc.status)
return ret < 0 ? ret : -EINVAL;
if (ret)
break;
} while (!time_after(jiffies, end));
if (!ret)
return -ETIMEDOUT;
if (wc.wr_id != WR_ID_BF)
ret = 0;
return ret;
}
static int test_wc_do_send(struct mlx5_ib_dev *dev, struct ib_qp *qp)
{
int err, i;
for (i = 0; i < TEST_WC_NUM_WQES; i++) {
err = post_send_nop(dev, qp, WR_ID_BF, false);
if (err)
return err;
}
return post_send_nop(dev, qp, WR_ID_END, true);
}
int mlx5_ib_test_wc(struct mlx5_ib_dev *dev)
{
struct ib_cq_init_attr cq_attr = { .cqe = TEST_WC_NUM_WQES + 1 };
int port_type_cap = MLX5_CAP_GEN(dev->mdev, port_type);
struct ib_qp_init_attr qp_init_attr = {
.cap = { .max_send_wr = TEST_WC_NUM_WQES },
.qp_type = IB_QPT_UD,
.sq_sig_type = IB_SIGNAL_REQ_WR,
.create_flags = MLX5_IB_QP_CREATE_WC_TEST,
};
struct ib_qp_attr qp_attr = { .port_num = 1 };
struct ib_device *ibdev = &dev->ib_dev;
struct ib_qp *qp;
struct ib_cq *cq;
struct ib_pd *pd;
int ret;
if (!MLX5_CAP_GEN(dev->mdev, bf))
return 0;
if (!dev->mdev->roce.roce_en &&
port_type_cap == MLX5_CAP_PORT_TYPE_ETH) {
if (mlx5_core_is_pf(dev->mdev))
dev->wc_support = arch_can_pci_mmap_wc();
return 0;
}
ret = mlx5_alloc_bfreg(dev->mdev, &dev->wc_bfreg, true, false);
if (ret)
goto print_err;
if (!dev->wc_bfreg.wc)
goto out1;
pd = ib_alloc_pd(ibdev, 0);
if (IS_ERR(pd)) {
ret = PTR_ERR(pd);
goto out1;
}
cq = ib_create_cq(ibdev, NULL, NULL, NULL, &cq_attr);
if (IS_ERR(cq)) {
ret = PTR_ERR(cq);
goto out2;
}
qp_init_attr.recv_cq = cq;
qp_init_attr.send_cq = cq;
qp = ib_create_qp(pd, &qp_init_attr);
if (IS_ERR(qp)) {
ret = PTR_ERR(qp);
goto out3;
}
qp_attr.qp_state = IB_QPS_INIT;
ret = ib_modify_qp(qp, &qp_attr,
IB_QP_STATE | IB_QP_PORT | IB_QP_PKEY_INDEX |
IB_QP_QKEY);
if (ret)
goto out4;
qp_attr.qp_state = IB_QPS_RTR;
ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
if (ret)
goto out4;
qp_attr.qp_state = IB_QPS_RTS;
ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE | IB_QP_SQ_PSN);
if (ret)
goto out4;
ret = test_wc_do_send(dev, qp);
if (ret < 0)
goto out4;
ret = test_wc_poll_cq_result(dev, cq);
if (ret > 0) {
dev->wc_support = true;
ret = 0;
}
out4:
ib_destroy_qp(qp);
out3:
ib_destroy_cq(cq);
out2:
ib_dealloc_pd(pd);
out1:
mlx5_free_bfreg(dev->mdev, &dev->wc_bfreg);
print_err:
if (ret)
mlx5_ib_err(
dev,
"Error %d while trying to test write-combining support\n",
ret);
return ret;
}