/*
* libcxgb_ppm.c: Chelsio common library for T3/T4/T5 iSCSI PagePod Manager
*
* Copyright (c) 2016 Chelsio Communications, Inc. 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.
*
* Written by: Karen Xie ([email protected])
*/
#define DRV_NAME "libcxgb"
#define pr_fmt(fmt) DRV_NAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/debugfs.h>
#include <linux/export.h>
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/pci.h>
#include <linux/scatterlist.h>
#include "libcxgb_ppm.h"
/* Direct Data Placement -
* Directly place the iSCSI Data-In or Data-Out PDU's payload into
* pre-posted final destination host-memory buffers based on the
* Initiator Task Tag (ITT) in Data-In or Target Task Tag (TTT)
* in Data-Out PDUs. The host memory address is programmed into
* h/w in the format of pagepod entries. The location of the
* pagepod entry is encoded into ddp tag which is used as the base
* for ITT/TTT.
*/
/* Direct-Data Placement page size adjustment
*/
int cxgbi_ppm_find_page_index(struct cxgbi_ppm *ppm, unsigned long pgsz)
{
struct cxgbi_tag_format *tformat = &ppm->tformat;
int i;
for (i = 0; i < DDP_PGIDX_MAX; i++) {
if (pgsz == 1UL << (DDP_PGSZ_BASE_SHIFT +
tformat->pgsz_order[i])) {
pr_debug("%s: %s ppm, pgsz %lu -> idx %d.\n",
__func__, ppm->ndev->name, pgsz, i);
return i;
}
}
pr_info("ippm: ddp page size %lu not supported.\n", pgsz);
return DDP_PGIDX_MAX;
}
/* DDP setup & teardown
*/
static int ppm_find_unused_entries(unsigned long *bmap,
unsigned int max_ppods,
unsigned int start,
unsigned int nr,
unsigned int align_mask)
{
unsigned long i;
i = bitmap_find_next_zero_area(bmap, max_ppods, start, nr, align_mask);
if (unlikely(i >= max_ppods) && (start > nr))
i = bitmap_find_next_zero_area(bmap, max_ppods, 0, start - 1,
align_mask);
if (unlikely(i >= max_ppods))
return -ENOSPC;
bitmap_set(bmap, i, nr);
return (int)i;
}
static void ppm_mark_entries(struct cxgbi_ppm *ppm, int i, int count,
unsigned long caller_data)
{
struct cxgbi_ppod_data *pdata = ppm->ppod_data + i;
pdata->caller_data = caller_data;
pdata->npods = count;
if (pdata->color == ((1 << PPOD_IDX_SHIFT) - 1))
pdata->color = 0;
else
pdata->color++;
}
static int ppm_get_cpu_entries(struct cxgbi_ppm *ppm, unsigned int count,
unsigned long caller_data)
{
struct cxgbi_ppm_pool *pool;
unsigned int cpu;
int i;
if (!ppm->pool)
return -EINVAL;
cpu = get_cpu();
pool = per_cpu_ptr(ppm->pool, cpu);
spin_lock_bh(&pool->lock);
put_cpu();
i = ppm_find_unused_entries(pool->bmap, ppm->pool_index_max,
pool->next, count, 0);
if (i < 0) {
pool->next = 0;
spin_unlock_bh(&pool->lock);
return -ENOSPC;
}
pool->next = i + count;
if (pool->next >= ppm->pool_index_max)
pool->next = 0;
spin_unlock_bh(&pool->lock);
pr_debug("%s: cpu %u, idx %d + %d (%d), next %u.\n",
__func__, cpu, i, count, i + cpu * ppm->pool_index_max,
pool->next);
i += cpu * ppm->pool_index_max;
ppm_mark_entries(ppm, i, count, caller_data);
return i;
}
static int ppm_get_entries(struct cxgbi_ppm *ppm, unsigned int count,
unsigned long caller_data)
{
int i;
spin_lock_bh(&ppm->map_lock);
i = ppm_find_unused_entries(ppm->ppod_bmap, ppm->bmap_index_max,
ppm->next, count, 0);
if (i < 0) {
ppm->next = 0;
spin_unlock_bh(&ppm->map_lock);
pr_debug("ippm: NO suitable entries %u available.\n",
count);
return -ENOSPC;
}
ppm->next = i + count;
if (ppm->max_index_in_edram && (ppm->next >= ppm->max_index_in_edram))
ppm->next = 0;
else if (ppm->next >= ppm->bmap_index_max)
ppm->next = 0;
spin_unlock_bh(&ppm->map_lock);
pr_debug("%s: idx %d + %d (%d), next %u, caller_data 0x%lx.\n",
__func__, i, count, i + ppm->pool_rsvd, ppm->next,
caller_data);
i += ppm->pool_rsvd;
ppm_mark_entries(ppm, i, count, caller_data);
return i;
}
static void ppm_unmark_entries(struct cxgbi_ppm *ppm, int i, int count)
{
pr_debug("%s: idx %d + %d.\n", __func__, i, count);
if (i < ppm->pool_rsvd) {
unsigned int cpu;
struct cxgbi_ppm_pool *pool;
cpu = i / ppm->pool_index_max;
i %= ppm->pool_index_max;
pool = per_cpu_ptr(ppm->pool, cpu);
spin_lock_bh(&pool->lock);
bitmap_clear(pool->bmap, i, count);
if (i < pool->next)
pool->next = i;
spin_unlock_bh(&pool->lock);
pr_debug("%s: cpu %u, idx %d, next %u.\n",
__func__, cpu, i, pool->next);
} else {
spin_lock_bh(&ppm->map_lock);
i -= ppm->pool_rsvd;
bitmap_clear(ppm->ppod_bmap, i, count);
if (i < ppm->next)
ppm->next = i;
spin_unlock_bh(&ppm->map_lock);
pr_debug("%s: idx %d, next %u.\n", __func__, i, ppm->next);
}
}
void cxgbi_ppm_ppod_release(struct cxgbi_ppm *ppm, u32 idx)
{
struct cxgbi_ppod_data *pdata;
if (idx >= ppm->ppmax) {
pr_warn("ippm: idx too big %u > %u.\n", idx, ppm->ppmax);
return;
}
pdata = ppm->ppod_data + idx;
if (!pdata->npods) {
pr_warn("ippm: idx %u, npods 0.\n", idx);
return;
}
pr_debug("release idx %u, npods %u.\n", idx, pdata->npods);
ppm_unmark_entries(ppm, idx, pdata->npods);
}
EXPORT_SYMBOL(cxgbi_ppm_ppod_release);
int cxgbi_ppm_ppods_reserve(struct cxgbi_ppm *ppm, unsigned short nr_pages,
u32 per_tag_pg_idx, u32 *ppod_idx,
u32 *ddp_tag, unsigned long caller_data)
{
struct cxgbi_ppod_data *pdata;
unsigned int npods;
int idx = -1;
unsigned int hwidx;
u32 tag;
npods = (nr_pages + PPOD_PAGES_MAX - 1) >> PPOD_PAGES_SHIFT;
if (!npods) {
pr_warn("%s: pages %u -> npods %u, full.\n",
__func__, nr_pages, npods);
return -EINVAL;
}
/* grab from cpu pool first */
idx = ppm_get_cpu_entries(ppm, npods, caller_data);
/* try the general pool */
if (idx < 0)
idx = ppm_get_entries(ppm, npods, caller_data);
if (idx < 0) {
pr_debug("ippm: pages %u, nospc %u, nxt %u, 0x%lx.\n",
nr_pages, npods, ppm->next, caller_data);
return idx;
}
pdata = ppm->ppod_data + idx;
hwidx = ppm->base_idx + idx;
tag = cxgbi_ppm_make_ddp_tag(hwidx, pdata->color);
if (per_tag_pg_idx)
tag |= (per_tag_pg_idx << 30) & 0xC0000000;
*ppod_idx = idx;
*ddp_tag = tag;
pr_debug("ippm: sg %u, tag 0x%x(%u,%u), data 0x%lx.\n",
nr_pages, tag, idx, npods, caller_data);
return npods;
}
EXPORT_SYMBOL(cxgbi_ppm_ppods_reserve);
void cxgbi_ppm_make_ppod_hdr(struct cxgbi_ppm *ppm, u32 tag,
unsigned int tid, unsigned int offset,
unsigned int length,
struct cxgbi_pagepod_hdr *hdr)
{
/* The ddp tag in pagepod should be with bit 31:30 set to 0.
* The ddp Tag on the wire should be with non-zero 31:30 to the peer
*/
tag &= 0x3FFFFFFF;
hdr->vld_tid = htonl(PPOD_VALID_FLAG | PPOD_TID(tid));
hdr->rsvd = 0;
hdr->pgsz_tag_clr = htonl(tag & ppm->tformat.idx_clr_mask);
hdr->max_offset = htonl(length);
hdr->page_offset = htonl(offset);
pr_debug("ippm: tag 0x%x, tid 0x%x, xfer %u, off %u.\n",
tag, tid, length, offset);
}
EXPORT_SYMBOL(cxgbi_ppm_make_ppod_hdr);
static void ppm_free(struct cxgbi_ppm *ppm)
{
vfree(ppm);
}
static void ppm_destroy(struct kref *kref)
{
struct cxgbi_ppm *ppm = container_of(kref,
struct cxgbi_ppm,
refcnt);
pr_info("ippm: kref 0, destroy %s ppm 0x%p.\n",
ppm->ndev->name, ppm);
*ppm->ppm_pp = NULL;
free_percpu(ppm->pool);
ppm_free(ppm);
}
int cxgbi_ppm_release(struct cxgbi_ppm *ppm)
{
if (ppm) {
int rv;
rv = kref_put(&ppm->refcnt, ppm_destroy);
return rv;
}
return 1;
}
EXPORT_SYMBOL(cxgbi_ppm_release);
static struct cxgbi_ppm_pool __percpu *
ppm_alloc_cpu_pool(unsigned int *total, unsigned int *pcpu_ppmax)
{
struct cxgbi_ppm_pool __percpu *pools;
unsigned int ppmax = (*total) / num_possible_cpus();
unsigned int max = (PCPU_MIN_UNIT_SIZE - sizeof(*pools)) << 3;
unsigned int bmap;
unsigned int alloc_sz;
unsigned int count = 0;
unsigned int cpu;
/* make sure per cpu pool fits into PCPU_MIN_UNIT_SIZE */
if (ppmax > max)
ppmax = max;
/* pool size must be multiple of unsigned long */
bmap = ppmax / BITS_PER_TYPE(unsigned long);
if (!bmap)
return NULL;
ppmax = (bmap * sizeof(unsigned long)) << 3;
alloc_sz = sizeof(*pools) + sizeof(unsigned long) * bmap;
pools = __alloc_percpu(alloc_sz, __alignof__(struct cxgbi_ppm_pool));
if (!pools)
return NULL;
for_each_possible_cpu(cpu) {
struct cxgbi_ppm_pool *ppool = per_cpu_ptr(pools, cpu);
memset(ppool, 0, alloc_sz);
spin_lock_init(&ppool->lock);
count += ppmax;
}
*total = count;
*pcpu_ppmax = ppmax;
return pools;
}
int cxgbi_ppm_init(void **ppm_pp, struct net_device *ndev,
struct pci_dev *pdev, void *lldev,
struct cxgbi_tag_format *tformat, unsigned int iscsi_size,
unsigned int llimit, unsigned int start,
unsigned int reserve_factor, unsigned int iscsi_edram_start,
unsigned int iscsi_edram_size)
{
struct cxgbi_ppm *ppm = (struct cxgbi_ppm *)(*ppm_pp);
struct cxgbi_ppm_pool __percpu *pool = NULL;
unsigned int pool_index_max = 0;
unsigned int ppmax_pool = 0;
unsigned int ppod_bmap_size;
unsigned int alloc_sz;
unsigned int ppmax;
if (!iscsi_edram_start)
iscsi_edram_size = 0;
if (iscsi_edram_size &&
((iscsi_edram_start + iscsi_edram_size) != start)) {
pr_err("iscsi ppod region not contiguous: EDRAM start 0x%x "
"size 0x%x DDR start 0x%x\n",
iscsi_edram_start, iscsi_edram_size, start);
return -EINVAL;
}
if (iscsi_edram_size) {
reserve_factor = 0;
start = iscsi_edram_start;
}
ppmax = (iscsi_edram_size + iscsi_size) >> PPOD_SIZE_SHIFT;
if (ppm) {
pr_info("ippm: %s, ppm 0x%p,0x%p already initialized, %u/%u.\n",
ndev->name, ppm_pp, ppm, ppm->ppmax, ppmax);
kref_get(&ppm->refcnt);
return 1;
}
if (reserve_factor) {
ppmax_pool = ppmax / reserve_factor;
pool = ppm_alloc_cpu_pool(&ppmax_pool, &pool_index_max);
if (!pool) {
ppmax_pool = 0;
reserve_factor = 0;
}
pr_debug("%s: ppmax %u, cpu total %u, per cpu %u.\n",
ndev->name, ppmax, ppmax_pool, pool_index_max);
}
ppod_bmap_size = BITS_TO_LONGS(ppmax - ppmax_pool);
alloc_sz = sizeof(struct cxgbi_ppm) +
ppmax * (sizeof(struct cxgbi_ppod_data)) +
ppod_bmap_size * sizeof(unsigned long);
ppm = vzalloc(alloc_sz);
if (!ppm)
goto release_ppm_pool;
ppm->ppod_bmap = (unsigned long *)(&ppm->ppod_data[ppmax]);
if ((ppod_bmap_size >> 3) > (ppmax - ppmax_pool)) {
unsigned int start = ppmax - ppmax_pool;
unsigned int end = ppod_bmap_size >> 3;
bitmap_set(ppm->ppod_bmap, ppmax, end - start);
pr_info("%s: %u - %u < %u * 8, mask extra bits %u, %u.\n",
__func__, ppmax, ppmax_pool, ppod_bmap_size, start,
end);
}
if (iscsi_edram_size) {
unsigned int first_ddr_idx =
iscsi_edram_size >> PPOD_SIZE_SHIFT;
ppm->max_index_in_edram = first_ddr_idx - 1;
bitmap_set(ppm->ppod_bmap, first_ddr_idx, 1);
pr_debug("reserved %u ppod in bitmap\n", first_ddr_idx);
}
spin_lock_init(&ppm->map_lock);
kref_init(&ppm->refcnt);
memcpy(&ppm->tformat, tformat, sizeof(struct cxgbi_tag_format));
ppm->ppm_pp = ppm_pp;
ppm->ndev = ndev;
ppm->pdev = pdev;
ppm->lldev = lldev;
ppm->ppmax = ppmax;
ppm->next = 0;
ppm->llimit = llimit;
ppm->base_idx = start > llimit ?
(start - llimit + 1) >> PPOD_SIZE_SHIFT : 0;
ppm->bmap_index_max = ppmax - ppmax_pool;
ppm->pool = pool;
ppm->pool_rsvd = ppmax_pool;
ppm->pool_index_max = pool_index_max;
/* check one more time */
if (*ppm_pp) {
ppm_free(ppm);
ppm = (struct cxgbi_ppm *)(*ppm_pp);
pr_info("ippm: %s, ppm 0x%p,0x%p already initialized, %u/%u.\n",
ndev->name, ppm_pp, *ppm_pp, ppm->ppmax, ppmax);
kref_get(&ppm->refcnt);
return 1;
}
*ppm_pp = ppm;
ppm->tformat.pgsz_idx_dflt = cxgbi_ppm_find_page_index(ppm, PAGE_SIZE);
pr_info("ippm %s: ppm 0x%p, 0x%p, base %u/%u, pg %lu,%u, rsvd %u,%u.\n",
ndev->name, ppm_pp, ppm, ppm->base_idx, ppm->ppmax, PAGE_SIZE,
ppm->tformat.pgsz_idx_dflt, ppm->pool_rsvd,
ppm->pool_index_max);
return 0;
release_ppm_pool:
free_percpu(pool);
return -ENOMEM;
}
EXPORT_SYMBOL(cxgbi_ppm_init);
unsigned int cxgbi_tagmask_set(unsigned int ppmax)
{
unsigned int bits = fls(ppmax);
if (bits > PPOD_IDX_MAX_SIZE)
bits = PPOD_IDX_MAX_SIZE;
pr_info("ippm: ppmax %u/0x%x -> bits %u, tagmask 0x%x.\n",
ppmax, ppmax, bits, 1 << (bits + PPOD_IDX_SHIFT));
return 1 << (bits + PPOD_IDX_SHIFT);
}
EXPORT_SYMBOL(cxgbi_tagmask_set);
MODULE_AUTHOR("Chelsio Communications");
MODULE_DESCRIPTION("Chelsio common library");
MODULE_LICENSE("Dual BSD/GPL");
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