/*
* Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
* Copyright (c) 2013-2014 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 <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/scatterlist.h>
#include "iscsi_iser.h"
static
int iser_fast_reg_fmr(struct iscsi_iser_task *iser_task,
struct iser_data_buf *mem,
struct iser_reg_resources *rsc,
struct iser_mem_reg *mem_reg);
static
int iser_fast_reg_mr(struct iscsi_iser_task *iser_task,
struct iser_data_buf *mem,
struct iser_reg_resources *rsc,
struct iser_mem_reg *mem_reg);
static struct iser_reg_ops fastreg_ops = {
.alloc_reg_res = iser_alloc_fastreg_pool,
.free_reg_res = iser_free_fastreg_pool,
.reg_mem = iser_fast_reg_mr,
.unreg_mem = iser_unreg_mem_fastreg,
.reg_desc_get = iser_reg_desc_get_fr,
.reg_desc_put = iser_reg_desc_put_fr,
};
static struct iser_reg_ops fmr_ops = {
.alloc_reg_res = iser_alloc_fmr_pool,
.free_reg_res = iser_free_fmr_pool,
.reg_mem = iser_fast_reg_fmr,
.unreg_mem = iser_unreg_mem_fmr,
.reg_desc_get = iser_reg_desc_get_fmr,
.reg_desc_put = iser_reg_desc_put_fmr,
};
int iser_assign_reg_ops(struct iser_device *device)
{
struct ib_device_attr *dev_attr = &device->dev_attr;
/* Assign function handles - based on FMR support */
if (device->ib_device->alloc_fmr && device->ib_device->dealloc_fmr &&
device->ib_device->map_phys_fmr && device->ib_device->unmap_fmr) {
iser_info("FMR supported, using FMR for registration\n");
device->reg_ops = &fmr_ops;
} else
if (dev_attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) {
iser_info("FastReg supported, using FastReg for registration\n");
device->reg_ops = &fastreg_ops;
} else {
iser_err("IB device does not support FMRs nor FastRegs, can't register memory\n");
return -1;
}
return 0;
}
struct iser_fr_desc *
iser_reg_desc_get_fr(struct ib_conn *ib_conn)
{
struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
struct iser_fr_desc *desc;
unsigned long flags;
spin_lock_irqsave(&fr_pool->lock, flags);
desc = list_first_entry(&fr_pool->list,
struct iser_fr_desc, list);
list_del(&desc->list);
spin_unlock_irqrestore(&fr_pool->lock, flags);
return desc;
}
void
iser_reg_desc_put_fr(struct ib_conn *ib_conn,
struct iser_fr_desc *desc)
{
struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
unsigned long flags;
spin_lock_irqsave(&fr_pool->lock, flags);
list_add(&desc->list, &fr_pool->list);
spin_unlock_irqrestore(&fr_pool->lock, flags);
}
struct iser_fr_desc *
iser_reg_desc_get_fmr(struct ib_conn *ib_conn)
{
struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
return list_first_entry(&fr_pool->list,
struct iser_fr_desc, list);
}
void
iser_reg_desc_put_fmr(struct ib_conn *ib_conn,
struct iser_fr_desc *desc)
{
}
#define IS_4K_ALIGNED(addr) ((((unsigned long)addr) & ~MASK_4K) == 0)
/**
* iser_sg_to_page_vec - Translates scatterlist entries to physical addresses
* and returns the length of resulting physical address array (may be less than
* the original due to possible compaction).
*
* we build a "page vec" under the assumption that the SG meets the RDMA
* alignment requirements. Other then the first and last SG elements, all
* the "internal" elements can be compacted into a list whose elements are
* dma addresses of physical pages. The code supports also the weird case
* where --few fragments of the same page-- are present in the SG as
* consecutive elements. Also, it handles one entry SG.
*/
static int iser_sg_to_page_vec(struct iser_data_buf *data,
struct ib_device *ibdev, u64 *pages,
int *offset, int *data_size)
{
struct scatterlist *sg, *sgl = data->sg;
u64 start_addr, end_addr, page, chunk_start = 0;
unsigned long total_sz = 0;
unsigned int dma_len;
int i, new_chunk, cur_page, last_ent = data->dma_nents - 1;
/* compute the offset of first element */
*offset = (u64) sgl[0].offset & ~MASK_4K;
new_chunk = 1;
cur_page = 0;
for_each_sg(sgl, sg, data->dma_nents, i) {
start_addr = ib_sg_dma_address(ibdev, sg);
if (new_chunk)
chunk_start = start_addr;
dma_len = ib_sg_dma_len(ibdev, sg);
end_addr = start_addr + dma_len;
total_sz += dma_len;
/* collect page fragments until aligned or end of SG list */
if (!IS_4K_ALIGNED(end_addr) && i < last_ent) {
new_chunk = 0;
continue;
}
new_chunk = 1;
/* address of the first page in the contiguous chunk;
masking relevant for the very first SG entry,
which might be unaligned */
page = chunk_start & MASK_4K;
do {
pages[cur_page++] = page;
page += SIZE_4K;
} while (page < end_addr);
}
*data_size = total_sz;
iser_dbg("page_vec->data_size:%d cur_page %d\n",
*data_size, cur_page);
return cur_page;
}
static void iser_data_buf_dump(struct iser_data_buf *data,
struct ib_device *ibdev)
{
struct scatterlist *sg;
int i;
for_each_sg(data->sg, sg, data->dma_nents, i)
iser_dbg("sg[%d] dma_addr:0x%lX page:0x%p "
"off:0x%x sz:0x%x dma_len:0x%x\n",
i, (unsigned long)ib_sg_dma_address(ibdev, sg),
sg_page(sg), sg->offset,
sg->length, ib_sg_dma_len(ibdev, sg));
}
static void iser_dump_page_vec(struct iser_page_vec *page_vec)
{
int i;
iser_err("page vec length %d data size %d\n",
page_vec->length, page_vec->data_size);
for (i = 0; i < page_vec->length; i++)
iser_err("%d %lx\n",i,(unsigned long)page_vec->pages[i]);
}
int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
struct iser_data_buf *data,
enum iser_data_dir iser_dir,
enum dma_data_direction dma_dir)
{
struct ib_device *dev;
iser_task->dir[iser_dir] = 1;
dev = iser_task->iser_conn->ib_conn.device->ib_device;
data->dma_nents = ib_dma_map_sg(dev, data->sg, data->size, dma_dir);
if (data->dma_nents == 0) {
iser_err("dma_map_sg failed!!!\n");
return -EINVAL;
}
return 0;
}
void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task,
struct iser_data_buf *data,
enum dma_data_direction dir)
{
struct ib_device *dev;
dev = iser_task->iser_conn->ib_conn.device->ib_device;
ib_dma_unmap_sg(dev, data->sg, data->size, dir);
}
static int
iser_reg_dma(struct iser_device *device, struct iser_data_buf *mem,
struct iser_mem_reg *reg)
{
struct scatterlist *sg = mem->sg;
reg->sge.lkey = device->pd->local_dma_lkey;
reg->rkey = device->mr->rkey;
reg->sge.addr = ib_sg_dma_address(device->ib_device, &sg[0]);
reg->sge.length = ib_sg_dma_len(device->ib_device, &sg[0]);
iser_dbg("Single DMA entry: lkey=0x%x, rkey=0x%x, addr=0x%llx,"
" length=0x%x\n", reg->sge.lkey, reg->rkey,
reg->sge.addr, reg->sge.length);
return 0;
}
/**
* iser_reg_page_vec - Register physical memory
*
* returns: 0 on success, errno code on failure
*/
static
int iser_fast_reg_fmr(struct iscsi_iser_task *iser_task,
struct iser_data_buf *mem,
struct iser_reg_resources *rsc,
struct iser_mem_reg *reg)
{
struct ib_conn *ib_conn = &iser_task->iser_conn->ib_conn;
struct iser_device *device = ib_conn->device;
struct iser_page_vec *page_vec = rsc->page_vec;
struct ib_fmr_pool *fmr_pool = rsc->fmr_pool;
struct ib_pool_fmr *fmr;
int ret, plen;
plen = iser_sg_to_page_vec(mem, device->ib_device,
page_vec->pages,
&page_vec->offset,
&page_vec->data_size);
page_vec->length = plen;
if (plen * SIZE_4K < page_vec->data_size) {
iser_err("page vec too short to hold this SG\n");
iser_data_buf_dump(mem, device->ib_device);
iser_dump_page_vec(page_vec);
return -EINVAL;
}
fmr = ib_fmr_pool_map_phys(fmr_pool,
page_vec->pages,
page_vec->length,
page_vec->pages[0]);
if (IS_ERR(fmr)) {
ret = PTR_ERR(fmr);
iser_err("ib_fmr_pool_map_phys failed: %d\n", ret);
return ret;
}
reg->sge.lkey = fmr->fmr->lkey;
reg->rkey = fmr->fmr->rkey;
reg->sge.addr = page_vec->pages[0] + page_vec->offset;
reg->sge.length = page_vec->data_size;
reg->mem_h = fmr;
iser_dbg("fmr reg: lkey=0x%x, rkey=0x%x, addr=0x%llx,"
" length=0x%x\n", reg->sge.lkey, reg->rkey,
reg->sge.addr, reg->sge.length);
return 0;
}
/**
* Unregister (previosuly registered using FMR) memory.
* If memory is non-FMR does nothing.
*/
void iser_unreg_mem_fmr(struct iscsi_iser_task *iser_task,
enum iser_data_dir cmd_dir)
{
struct iser_mem_reg *reg = &iser_task->rdma_reg[cmd_dir];
int ret;
if (!reg->mem_h)
return;
iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n", reg->mem_h);
ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h);
if (ret)
iser_err("ib_fmr_pool_unmap failed %d\n", ret);
reg->mem_h = NULL;
}
void iser_unreg_mem_fastreg(struct iscsi_iser_task *iser_task,
enum iser_data_dir cmd_dir)
{
struct iser_device *device = iser_task->iser_conn->ib_conn.device;
struct iser_mem_reg *reg = &iser_task->rdma_reg[cmd_dir];
if (!reg->mem_h)
return;
device->reg_ops->reg_desc_put(&iser_task->iser_conn->ib_conn,
reg->mem_h);
reg->mem_h = NULL;
}
static void
iser_set_dif_domain(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs,
struct ib_sig_domain *domain)
{
domain->sig_type = IB_SIG_TYPE_T10_DIF;
domain->sig.dif.pi_interval = scsi_prot_interval(sc);
domain->sig.dif.ref_tag = scsi_prot_ref_tag(sc);
/*
* At the moment we hard code those, but in the future
* we will take them from sc.
*/
domain->sig.dif.apptag_check_mask = 0xffff;
domain->sig.dif.app_escape = true;
domain->sig.dif.ref_escape = true;
if (sc->prot_flags & SCSI_PROT_REF_INCREMENT)
domain->sig.dif.ref_remap = true;
};
static int
iser_set_sig_attrs(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs)
{
switch (scsi_get_prot_op(sc)) {
case SCSI_PROT_WRITE_INSERT:
case SCSI_PROT_READ_STRIP:
sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
iser_set_dif_domain(sc, sig_attrs, &sig_attrs->wire);
sig_attrs->wire.sig.dif.bg_type = IB_T10DIF_CRC;
break;
case SCSI_PROT_READ_INSERT:
case SCSI_PROT_WRITE_STRIP:
sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
iser_set_dif_domain(sc, sig_attrs, &sig_attrs->mem);
sig_attrs->mem.sig.dif.bg_type = sc->prot_flags & SCSI_PROT_IP_CHECKSUM ?
IB_T10DIF_CSUM : IB_T10DIF_CRC;
break;
case SCSI_PROT_READ_PASS:
case SCSI_PROT_WRITE_PASS:
iser_set_dif_domain(sc, sig_attrs, &sig_attrs->wire);
sig_attrs->wire.sig.dif.bg_type = IB_T10DIF_CRC;
iser_set_dif_domain(sc, sig_attrs, &sig_attrs->mem);
sig_attrs->mem.sig.dif.bg_type = sc->prot_flags & SCSI_PROT_IP_CHECKSUM ?
IB_T10DIF_CSUM : IB_T10DIF_CRC;
break;
default:
iser_err("Unsupported PI operation %d\n",
scsi_get_prot_op(sc));
return -EINVAL;
}
return 0;
}
static inline void
iser_set_prot_checks(struct scsi_cmnd *sc, u8 *mask)
{
*mask = 0;
if (sc->prot_flags & SCSI_PROT_REF_CHECK)
*mask |= ISER_CHECK_REFTAG;
if (sc->prot_flags & SCSI_PROT_GUARD_CHECK)
*mask |= ISER_CHECK_GUARD;
}
static void
iser_inv_rkey(struct ib_send_wr *inv_wr, struct ib_mr *mr)
{
u32 rkey;
inv_wr->opcode = IB_WR_LOCAL_INV;
inv_wr->wr_id = ISER_FASTREG_LI_WRID;
inv_wr->ex.invalidate_rkey = mr->rkey;
inv_wr->send_flags = 0;
inv_wr->num_sge = 0;
rkey = ib_inc_rkey(mr->rkey);
ib_update_fast_reg_key(mr, rkey);
}
static int
iser_reg_sig_mr(struct iscsi_iser_task *iser_task,
struct iser_pi_context *pi_ctx,
struct iser_mem_reg *data_reg,
struct iser_mem_reg *prot_reg,
struct iser_mem_reg *sig_reg)
{
struct iser_tx_desc *tx_desc = &iser_task->desc;
struct ib_sig_attrs *sig_attrs = &tx_desc->sig_attrs;
struct ib_sig_handover_wr *wr;
int ret;
memset(sig_attrs, 0, sizeof(*sig_attrs));
ret = iser_set_sig_attrs(iser_task->sc, sig_attrs);
if (ret)
goto err;
iser_set_prot_checks(iser_task->sc, &sig_attrs->check_mask);
if (!pi_ctx->sig_mr_valid)
iser_inv_rkey(iser_tx_next_wr(tx_desc), pi_ctx->sig_mr);
wr = sig_handover_wr(iser_tx_next_wr(tx_desc));
wr->wr.opcode = IB_WR_REG_SIG_MR;
wr->wr.wr_id = ISER_FASTREG_LI_WRID;
wr->wr.sg_list = &data_reg->sge;
wr->wr.num_sge = 1;
wr->wr.send_flags = 0;
wr->sig_attrs = sig_attrs;
wr->sig_mr = pi_ctx->sig_mr;
if (scsi_prot_sg_count(iser_task->sc))
wr->prot = &prot_reg->sge;
else
wr->prot = NULL;
wr->access_flags = IB_ACCESS_LOCAL_WRITE |
IB_ACCESS_REMOTE_READ |
IB_ACCESS_REMOTE_WRITE;
pi_ctx->sig_mr_valid = 0;
sig_reg->sge.lkey = pi_ctx->sig_mr->lkey;
sig_reg->rkey = pi_ctx->sig_mr->rkey;
sig_reg->sge.addr = 0;
sig_reg->sge.length = scsi_transfer_length(iser_task->sc);
iser_dbg("lkey=0x%x rkey=0x%x addr=0x%llx length=%u\n",
sig_reg->sge.lkey, sig_reg->rkey, sig_reg->sge.addr,
sig_reg->sge.length);
err:
return ret;
}
static int iser_fast_reg_mr(struct iscsi_iser_task *iser_task,
struct iser_data_buf *mem,
struct iser_reg_resources *rsc,
struct iser_mem_reg *reg)
{
struct iser_tx_desc *tx_desc = &iser_task->desc;
struct ib_mr *mr = rsc->mr;
struct ib_reg_wr *wr;
int n;
if (!rsc->mr_valid)
iser_inv_rkey(iser_tx_next_wr(tx_desc), mr);
n = ib_map_mr_sg(mr, mem->sg, mem->size, SIZE_4K);
if (unlikely(n != mem->size)) {
iser_err("failed to map sg (%d/%d)\n",
n, mem->size);
return n < 0 ? n : -EINVAL;
}
wr = reg_wr(iser_tx_next_wr(tx_desc));
wr->wr.opcode = IB_WR_REG_MR;
wr->wr.wr_id = ISER_FASTREG_LI_WRID;
wr->wr.send_flags = 0;
wr->wr.num_sge = 0;
wr->mr = mr;
wr->key = mr->rkey;
wr->access = IB_ACCESS_LOCAL_WRITE |
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_REMOTE_READ;
rsc->mr_valid = 0;
reg->sge.lkey = mr->lkey;
reg->rkey = mr->rkey;
reg->sge.addr = mr->iova;
reg->sge.length = mr->length;
iser_dbg("lkey=0x%x rkey=0x%x addr=0x%llx length=0x%x\n",
reg->sge.lkey, reg->rkey, reg->sge.addr, reg->sge.length);
return 0;
}
static int
iser_reg_prot_sg(struct iscsi_iser_task *task,
struct iser_data_buf *mem,
struct iser_fr_desc *desc,
bool use_dma_key,
struct iser_mem_reg *reg)
{
struct iser_device *device = task->iser_conn->ib_conn.device;
if (use_dma_key)
return iser_reg_dma(device, mem, reg);
return device->reg_ops->reg_mem(task, mem, &desc->pi_ctx->rsc, reg);
}
static int
iser_reg_data_sg(struct iscsi_iser_task *task,
struct iser_data_buf *mem,
struct iser_fr_desc *desc,
bool use_dma_key,
struct iser_mem_reg *reg)
{
struct iser_device *device = task->iser_conn->ib_conn.device;
if (use_dma_key)
return iser_reg_dma(device, mem, reg);
return device->reg_ops->reg_mem(task, mem, &desc->rsc, reg);
}
int iser_reg_rdma_mem(struct iscsi_iser_task *task,
enum iser_data_dir dir)
{
struct ib_conn *ib_conn = &task->iser_conn->ib_conn;
struct iser_device *device = ib_conn->device;
struct iser_data_buf *mem = &task->data[dir];
struct iser_mem_reg *reg = &task->rdma_reg[dir];
struct iser_mem_reg *data_reg;
struct iser_fr_desc *desc = NULL;
bool use_dma_key;
int err;
use_dma_key = (mem->dma_nents == 1 && !iser_always_reg &&
scsi_get_prot_op(task->sc) == SCSI_PROT_NORMAL);
if (!use_dma_key) {
desc = device->reg_ops->reg_desc_get(ib_conn);
reg->mem_h = desc;
}
if (scsi_get_prot_op(task->sc) == SCSI_PROT_NORMAL)
data_reg = reg;
else
data_reg = &task->desc.data_reg;
err = iser_reg_data_sg(task, mem, desc, use_dma_key, data_reg);
if (unlikely(err))
goto err_reg;
if (scsi_get_prot_op(task->sc) != SCSI_PROT_NORMAL) {
struct iser_mem_reg *prot_reg = &task->desc.prot_reg;
if (scsi_prot_sg_count(task->sc)) {
mem = &task->prot[dir];
err = iser_reg_prot_sg(task, mem, desc,
use_dma_key, prot_reg);
if (unlikely(err))
goto err_reg;
}
err = iser_reg_sig_mr(task, desc->pi_ctx, data_reg,
prot_reg, reg);
if (unlikely(err))
goto err_reg;
desc->pi_ctx->sig_protected = 1;
}
return 0;
err_reg:
if (desc)
device->reg_ops->reg_desc_put(ib_conn, desc);
return err;
}
void iser_unreg_rdma_mem(struct iscsi_iser_task *task,
enum iser_data_dir dir)
{
struct iser_device *device = task->iser_conn->ib_conn.device;
device->reg_ops->unreg_mem(task, dir);
}
