linux_dsm_epyc7002/drivers/infiniband/hw/mlx5/mem.c
Ilya Lesokhin d67bc5d4e3 IB/mlx5: Simplify mlx5_ib_cont_pages
The patch simplifies mlx5_ib_cont_pages and fixes the following
issues in the original implementation:

First issues is related to alignment of the PFNs. After the check
base + p != PFN, the alignment of the PFN wasn't checked. So the PFN
sequence 0, 1, 1, 2 would result in a page_shift of 13 even though
the 3rd PFN is not 8KB aligned.

This wasn't actually a bug because it was supported by all the
existing mlx5 compatible device, but we don't want to require
this support in all future devices.

Another issue is because the inner loop didn't advance PFN so
the test "if (base + p != pfn)" always failed for SGE with
len > (1<<page_shift).

Fixes: e126ba97db ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Reviewed-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-09-25 11:47:24 -04:00

235 lines
6.1 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"
/* @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;
unsigned long page_shift = umem->page_shift;
if (umem->odp_data) {
*ncont = ib_umem_page_count(umem);
*count = *ncont << (page_shift - PAGE_SHIFT);
*shift = page_shift;
if (order)
*order = ilog2(roundup_pow_of_two(*ncont));
return;
}
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;
}
#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
{
u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
if (umem_dma & ODP_READ_ALLOWED_BIT)
mtt_entry |= MLX5_IB_MTT_READ;
if (umem_dma & ODP_WRITE_ALLOWED_BIT)
mtt_entry |= MLX5_IB_MTT_WRITE;
return mtt_entry;
}
#endif
/*
* 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)
{
unsigned long umem_page_shift = umem->page_shift;
int shift = page_shift - umem_page_shift;
int mask = (1 << shift) - 1;
int i, k, idx;
u64 cur = 0;
u64 base;
int len;
struct scatterlist *sg;
int entry;
#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
const bool odp = umem->odp_data != NULL;
if (odp) {
WARN_ON(shift != 0);
WARN_ON(access_flags != (MLX5_IB_MTT_READ | MLX5_IB_MTT_WRITE));
for (i = 0; i < num_pages; ++i) {
dma_addr_t pa = umem->odp_data->dma_list[offset + i];
pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
}
return;
}
#endif
i = 0;
for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
len = sg_dma_len(sg) >> umem_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 << umem_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;
}