linux/net/smc/smc_core.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* Basic Transport Functions exploiting Infiniband API
*
* Copyright IBM Corp. 2016
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
*/
#include <linux/socket.h>
#include <linux/if_vlan.h>
#include <linux/random.h>
#include <linux/workqueue.h>
#include <net/tcp.h>
#include <net/sock.h>
#include <rdma/ib_verbs.h>
#include "smc.h"
#include "smc_clc.h"
#include "smc_core.h"
#include "smc_ib.h"
#include "smc_wr.h"
#include "smc_llc.h"
#include "smc_cdc.h"
#include "smc_close.h"
#define SMC_LGR_NUM_INCR 256
#define SMC_LGR_FREE_DELAY_SERV (600 * HZ)
#define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10)
static u32 smc_lgr_num; /* unique link group number */
/* Register connection's alert token in our lookup structure.
* To use rbtrees we have to implement our own insert core.
* Requires @conns_lock
* @smc connection to register
* Returns 0 on success, != otherwise.
*/
static void smc_lgr_add_alert_token(struct smc_connection *conn)
{
struct rb_node **link, *parent = NULL;
u32 token = conn->alert_token_local;
link = &conn->lgr->conns_all.rb_node;
while (*link) {
struct smc_connection *cur = rb_entry(*link,
struct smc_connection, alert_node);
parent = *link;
if (cur->alert_token_local > token)
link = &parent->rb_left;
else
link = &parent->rb_right;
}
/* Put the new node there */
rb_link_node(&conn->alert_node, parent, link);
rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
}
/* Register connection in link group by assigning an alert token
* registered in a search tree.
* Requires @conns_lock
* Note that '0' is a reserved value and not assigned.
*/
static void smc_lgr_register_conn(struct smc_connection *conn)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
static atomic_t nexttoken = ATOMIC_INIT(0);
/* find a new alert_token_local value not yet used by some connection
* in this link group
*/
sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
while (!conn->alert_token_local) {
conn->alert_token_local = atomic_inc_return(&nexttoken);
if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
conn->alert_token_local = 0;
}
smc_lgr_add_alert_token(conn);
conn->lgr->conns_num++;
}
/* Unregister connection and reset the alert token of the given connection<
*/
static void __smc_lgr_unregister_conn(struct smc_connection *conn)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
struct smc_link_group *lgr = conn->lgr;
rb_erase(&conn->alert_node, &lgr->conns_all);
lgr->conns_num--;
conn->alert_token_local = 0;
conn->lgr = NULL;
sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
}
/* Unregister connection and trigger lgr freeing if applicable
*/
static void smc_lgr_unregister_conn(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
int reduced = 0;
write_lock_bh(&lgr->conns_lock);
if (conn->alert_token_local) {
reduced = 1;
__smc_lgr_unregister_conn(conn);
}
write_unlock_bh(&lgr->conns_lock);
if (!reduced || lgr->conns_num)
return;
/* client link group creation always follows the server link group
* creation. For client use a somewhat higher removal delay time,
* otherwise there is a risk of out-of-sync link groups.
*/
mod_delayed_work(system_wq, &lgr->free_work,
lgr->role == SMC_CLNT ? SMC_LGR_FREE_DELAY_CLNT :
SMC_LGR_FREE_DELAY_SERV);
}
static void smc_lgr_free_work(struct work_struct *work)
{
struct smc_link_group *lgr = container_of(to_delayed_work(work),
struct smc_link_group,
free_work);
bool conns;
spin_lock_bh(&smc_lgr_list.lock);
read_lock_bh(&lgr->conns_lock);
conns = RB_EMPTY_ROOT(&lgr->conns_all);
read_unlock_bh(&lgr->conns_lock);
if (!conns) { /* number of lgr connections is no longer zero */
spin_unlock_bh(&smc_lgr_list.lock);
return;
}
list_del_init(&lgr->list); /* remove from smc_lgr_list */
spin_unlock_bh(&smc_lgr_list.lock);
smc_lgr_free(lgr);
}
/* create a new SMC link group */
static int smc_lgr_create(struct smc_sock *smc, __be32 peer_in_addr,
struct smc_ib_device *smcibdev, u8 ibport,
char *peer_systemid, unsigned short vlan_id)
{
struct smc_link_group *lgr;
struct smc_link *lnk;
u8 rndvec[3];
int rc = 0;
int i;
lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
if (!lgr) {
rc = -ENOMEM;
goto out;
}
lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
lgr->sync_err = false;
lgr->daddr = peer_in_addr;
memcpy(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN);
lgr->vlan_id = vlan_id;
rwlock_init(&lgr->sndbufs_lock);
rwlock_init(&lgr->rmbs_lock);
for (i = 0; i < SMC_RMBE_SIZES; i++) {
INIT_LIST_HEAD(&lgr->sndbufs[i]);
INIT_LIST_HEAD(&lgr->rmbs[i]);
}
smc_lgr_num += SMC_LGR_NUM_INCR;
memcpy(&lgr->id, (u8 *)&smc_lgr_num, SMC_LGR_ID_SIZE);
INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
lgr->conns_all = RB_ROOT;
lnk = &lgr->lnk[SMC_SINGLE_LINK];
/* initialize link */
lnk->smcibdev = smcibdev;
lnk->ibport = ibport;
lnk->path_mtu = smcibdev->pattr[ibport - 1].active_mtu;
if (!smcibdev->initialized)
smc_ib_setup_per_ibdev(smcibdev);
get_random_bytes(rndvec, sizeof(rndvec));
lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + (rndvec[2] << 16);
rc = smc_wr_alloc_link_mem(lnk);
if (rc)
goto free_lgr;
rc = smc_ib_create_protection_domain(lnk);
if (rc)
goto free_link_mem;
rc = smc_ib_create_queue_pair(lnk);
if (rc)
goto dealloc_pd;
rc = smc_wr_create_link(lnk);
if (rc)
goto destroy_qp;
init_completion(&lnk->llc_confirm);
init_completion(&lnk->llc_confirm_resp);
smc->conn.lgr = lgr;
rwlock_init(&lgr->conns_lock);
spin_lock_bh(&smc_lgr_list.lock);
list_add(&lgr->list, &smc_lgr_list.list);
spin_unlock_bh(&smc_lgr_list.lock);
return 0;
destroy_qp:
smc_ib_destroy_queue_pair(lnk);
dealloc_pd:
smc_ib_dealloc_protection_domain(lnk);
free_link_mem:
smc_wr_free_link_mem(lnk);
free_lgr:
kfree(lgr);
out:
return rc;
}
static void smc_buf_unuse(struct smc_connection *conn)
{
if (conn->sndbuf_desc) {
conn->sndbuf_desc->used = 0;
conn->sndbuf_size = 0;
}
if (conn->rmb_desc) {
conn->rmb_desc->reused = true;
conn->rmb_desc->used = 0;
conn->rmbe_size = 0;
}
}
/* remove a finished connection from its link group */
void smc_conn_free(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
if (!lgr)
return;
smc_cdc_tx_dismiss_slots(conn);
smc_lgr_unregister_conn(conn);
smc_buf_unuse(conn);
}
static void smc_link_clear(struct smc_link *lnk)
{
lnk->peer_qpn = 0;
smc_ib_modify_qp_reset(lnk);
smc_wr_free_link(lnk);
smc_ib_destroy_queue_pair(lnk);
smc_ib_dealloc_protection_domain(lnk);
smc_wr_free_link_mem(lnk);
}
static void smc_buf_free(struct smc_buf_desc *buf_desc, struct smc_link *lnk,
bool is_rmb)
{
if (is_rmb) {
if (buf_desc->mr_rx[SMC_SINGLE_LINK])
smc_ib_put_memory_region(
buf_desc->mr_rx[SMC_SINGLE_LINK]);
smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc,
DMA_FROM_DEVICE);
} else {
smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc,
DMA_TO_DEVICE);
}
sg_free_table(&buf_desc->sgt[SMC_SINGLE_LINK]);
if (buf_desc->cpu_addr)
free_pages((unsigned long)buf_desc->cpu_addr, buf_desc->order);
kfree(buf_desc);
}
static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
{
struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
struct smc_buf_desc *buf_desc, *bf_desc;
struct list_head *buf_list;
int i;
for (i = 0; i < SMC_RMBE_SIZES; i++) {
if (is_rmb)
buf_list = &lgr->rmbs[i];
else
buf_list = &lgr->sndbufs[i];
list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
list) {
list_del(&buf_desc->list);
smc_buf_free(buf_desc, lnk, is_rmb);
}
}
}
static void smc_lgr_free_bufs(struct smc_link_group *lgr)
{
/* free send buffers */
__smc_lgr_free_bufs(lgr, false);
/* free rmbs */
__smc_lgr_free_bufs(lgr, true);
}
/* remove a link group */
void smc_lgr_free(struct smc_link_group *lgr)
{
smc_lgr_free_bufs(lgr);
smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]);
kfree(lgr);
}
/* terminate linkgroup abnormally */
void smc_lgr_terminate(struct smc_link_group *lgr)
{
struct smc_connection *conn;
struct smc_sock *smc;
struct rb_node *node;
spin_lock_bh(&smc_lgr_list.lock);
if (list_empty(&lgr->list)) {
/* termination already triggered */
spin_unlock_bh(&smc_lgr_list.lock);
return;
}
/* do not use this link group for new connections */
list_del_init(&lgr->list);
spin_unlock_bh(&smc_lgr_list.lock);
write_lock_bh(&lgr->conns_lock);
node = rb_first(&lgr->conns_all);
while (node) {
conn = rb_entry(node, struct smc_connection, alert_node);
smc = container_of(conn, struct smc_sock, conn);
sock_hold(&smc->sk);
__smc_lgr_unregister_conn(conn);
schedule_work(&conn->close_work);
sock_put(&smc->sk);
node = rb_first(&lgr->conns_all);
}
write_unlock_bh(&lgr->conns_lock);
}
/* Determine vlan of internal TCP socket.
* @vlan_id: address to store the determined vlan id into
*/
static int smc_vlan_by_tcpsk(struct socket *clcsock, unsigned short *vlan_id)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
int rc = 0;
*vlan_id = 0;
if (!dst) {
rc = -ENOTCONN;
goto out;
}
if (!dst->dev) {
rc = -ENODEV;
goto out_rel;
}
if (is_vlan_dev(dst->dev))
*vlan_id = vlan_dev_vlan_id(dst->dev);
out_rel:
dst_release(dst);
out:
return rc;
}
/* determine the link gid matching the vlan id of the link group */
static int smc_link_determine_gid(struct smc_link_group *lgr)
{
struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
struct ib_gid_attr gattr;
union ib_gid gid;
int i;
if (!lgr->vlan_id) {
lnk->gid = lnk->smcibdev->gid[lnk->ibport - 1];
return 0;
}
for (i = 0; i < lnk->smcibdev->pattr[lnk->ibport - 1].gid_tbl_len;
i++) {
if (ib_query_gid(lnk->smcibdev->ibdev, lnk->ibport, i, &gid,
&gattr))
continue;
if (gattr.ndev) {
if (is_vlan_dev(gattr.ndev) &&
vlan_dev_vlan_id(gattr.ndev) == lgr->vlan_id) {
lnk->gid = gid;
dev_put(gattr.ndev);
return 0;
}
dev_put(gattr.ndev);
}
}
return -ENODEV;
}
/* create a new SMC connection (and a new link group if necessary) */
int smc_conn_create(struct smc_sock *smc, __be32 peer_in_addr,
struct smc_ib_device *smcibdev, u8 ibport,
struct smc_clc_msg_local *lcl, int srv_first_contact)
{
struct smc_connection *conn = &smc->conn;
struct smc_link_group *lgr;
unsigned short vlan_id;
enum smc_lgr_role role;
int local_contact = SMC_FIRST_CONTACT;
int rc = 0;
role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
rc = smc_vlan_by_tcpsk(smc->clcsock, &vlan_id);
if (rc)
return rc;
if ((role == SMC_CLNT) && srv_first_contact)
/* create new link group as well */
goto create;
/* determine if an existing link group can be reused */
spin_lock_bh(&smc_lgr_list.lock);
list_for_each_entry(lgr, &smc_lgr_list.list, list) {
write_lock_bh(&lgr->conns_lock);
if (!memcmp(lgr->peer_systemid, lcl->id_for_peer,
SMC_SYSTEMID_LEN) &&
!memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_gid, &lcl->gid,
SMC_GID_SIZE) &&
!memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_mac, lcl->mac,
sizeof(lcl->mac)) &&
!lgr->sync_err &&
(lgr->role == role) &&
(lgr->vlan_id == vlan_id) &&
((role == SMC_CLNT) ||
(lgr->conns_num < SMC_RMBS_PER_LGR_MAX))) {
/* link group found */
local_contact = SMC_REUSE_CONTACT;
conn->lgr = lgr;
smc_lgr_register_conn(conn); /* add smc conn to lgr */
write_unlock_bh(&lgr->conns_lock);
break;
}
write_unlock_bh(&lgr->conns_lock);
}
spin_unlock_bh(&smc_lgr_list.lock);
if (role == SMC_CLNT && !srv_first_contact &&
(local_contact == SMC_FIRST_CONTACT)) {
/* Server reuses a link group, but Client wants to start
* a new one
* send out_of_sync decline, reason synchr. error
*/
return -ENOLINK;
}
create:
if (local_contact == SMC_FIRST_CONTACT) {
rc = smc_lgr_create(smc, peer_in_addr, smcibdev, ibport,
lcl->id_for_peer, vlan_id);
if (rc)
goto out;
smc_lgr_register_conn(conn); /* add smc conn to lgr */
rc = smc_link_determine_gid(conn->lgr);
}
conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
conn->local_tx_ctrl.len = sizeof(struct smc_cdc_msg);
#ifndef KERNEL_HAS_ATOMIC64
spin_lock_init(&conn->acurs_lock);
#endif
out:
return rc ? rc : local_contact;
}
/* try to reuse a sndbuf or rmb description slot for a certain
* buffer size; if not available, return NULL
*/
static inline
struct smc_buf_desc *smc_buf_get_slot(struct smc_link_group *lgr,
int compressed_bufsize,
rwlock_t *lock,
struct list_head *buf_list)
{
struct smc_buf_desc *buf_slot;
read_lock_bh(lock);
list_for_each_entry(buf_slot, buf_list, list) {
if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
read_unlock_bh(lock);
return buf_slot;
}
}
read_unlock_bh(lock);
return NULL;
}
/* one of the conditions for announcing a receiver's current window size is
* that it "results in a minimum increase in the window size of 10% of the
* receive buffer space" [RFC7609]
*/
static inline int smc_rmb_wnd_update_limit(int rmbe_size)
{
return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
}
static struct smc_buf_desc *smc_new_buf_create(struct smc_link_group *lgr,
bool is_rmb, int bufsize)
{
struct smc_buf_desc *buf_desc;
struct smc_link *lnk;
int rc;
/* try to alloc a new buffer */
buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
if (!buf_desc)
return ERR_PTR(-ENOMEM);
buf_desc->cpu_addr =
(void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN |
__GFP_NOMEMALLOC |
__GFP_NORETRY | __GFP_ZERO,
get_order(bufsize));
if (!buf_desc->cpu_addr) {
kfree(buf_desc);
return ERR_PTR(-EAGAIN);
}
buf_desc->order = get_order(bufsize);
/* build the sg table from the pages */
lnk = &lgr->lnk[SMC_SINGLE_LINK];
rc = sg_alloc_table(&buf_desc->sgt[SMC_SINGLE_LINK], 1,
GFP_KERNEL);
if (rc) {
smc_buf_free(buf_desc, lnk, is_rmb);
return ERR_PTR(rc);
}
sg_set_buf(buf_desc->sgt[SMC_SINGLE_LINK].sgl,
buf_desc->cpu_addr, bufsize);
/* map sg table to DMA address */
rc = smc_ib_buf_map_sg(lnk->smcibdev, buf_desc,
is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
/* SMC protocol depends on mapping to one DMA address only */
if (rc != 1) {
smc_buf_free(buf_desc, lnk, is_rmb);
return ERR_PTR(-EAGAIN);
}
/* create a new memory region for the RMB */
if (is_rmb) {
rc = smc_ib_get_memory_region(lnk->roce_pd,
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_LOCAL_WRITE,
buf_desc);
if (rc) {
smc_buf_free(buf_desc, lnk, is_rmb);
return ERR_PTR(rc);
}
}
return buf_desc;
}
static int __smc_buf_create(struct smc_sock *smc, bool is_rmb)
{
struct smc_connection *conn = &smc->conn;
struct smc_link_group *lgr = conn->lgr;
struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
struct list_head *buf_list;
int bufsize, bufsize_short;
int sk_buf_size;
rwlock_t *lock;
if (is_rmb)
/* use socket recv buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_rcvbuf / 2;
else
/* use socket send buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_sndbuf / 2;
for (bufsize_short = smc_compress_bufsize(sk_buf_size);
bufsize_short >= 0; bufsize_short--) {
if (is_rmb) {
lock = &lgr->rmbs_lock;
buf_list = &lgr->rmbs[bufsize_short];
} else {
lock = &lgr->sndbufs_lock;
buf_list = &lgr->sndbufs[bufsize_short];
}
bufsize = smc_uncompress_bufsize(bufsize_short);
if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC)
continue;
/* check for reusable slot in the link group */
buf_desc = smc_buf_get_slot(lgr, bufsize_short, lock, buf_list);
if (buf_desc) {
memset(buf_desc->cpu_addr, 0, bufsize);
break; /* found reusable slot */
}
buf_desc = smc_new_buf_create(lgr, is_rmb, bufsize);
if (PTR_ERR(buf_desc) == -ENOMEM)
break;
if (IS_ERR(buf_desc))
continue;
buf_desc->used = 1;
write_lock_bh(lock);
list_add(&buf_desc->list, buf_list);
write_unlock_bh(lock);
break; /* found */
}
if (IS_ERR(buf_desc))
return -ENOMEM;
if (is_rmb) {
conn->rmb_desc = buf_desc;
conn->rmbe_size = bufsize;
conn->rmbe_size_short = bufsize_short;
smc->sk.sk_rcvbuf = bufsize * 2;
atomic_set(&conn->bytes_to_rcv, 0);
conn->rmbe_update_limit = smc_rmb_wnd_update_limit(bufsize);
} else {
conn->sndbuf_desc = buf_desc;
conn->sndbuf_size = bufsize;
smc->sk.sk_sndbuf = bufsize * 2;
atomic_set(&conn->sndbuf_space, bufsize);
}
return 0;
}
void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
smc_ib_sync_sg_for_cpu(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
conn->sndbuf_desc, DMA_TO_DEVICE);
}
void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
smc_ib_sync_sg_for_device(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
conn->sndbuf_desc, DMA_TO_DEVICE);
}
void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
smc_ib_sync_sg_for_cpu(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
conn->rmb_desc, DMA_FROM_DEVICE);
}
void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
smc_ib_sync_sg_for_device(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
conn->rmb_desc, DMA_FROM_DEVICE);
}
/* create the send and receive buffer for an SMC socket;
* receive buffers are called RMBs;
* (even though the SMC protocol allows more than one RMB-element per RMB,
* the Linux implementation uses just one RMB-element per RMB, i.e. uses an
* extra RMB for every connection in a link group
*/
int smc_buf_create(struct smc_sock *smc)
{
int rc;
/* create send buffer */
rc = __smc_buf_create(smc, false);
if (rc)
return rc;
/* create rmb */
rc = __smc_buf_create(smc, true);
if (rc)
smc_buf_free(smc->conn.sndbuf_desc,
&smc->conn.lgr->lnk[SMC_SINGLE_LINK], false);
return rc;
}
static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
{
int i;
for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
if (!test_and_set_bit(i, lgr->rtokens_used_mask))
return i;
}
return -ENOSPC;
}
/* save rkey and dma_addr received from peer during clc handshake */
int smc_rmb_rtoken_handling(struct smc_connection *conn,
struct smc_clc_msg_accept_confirm *clc)
{
u64 dma_addr = be64_to_cpu(clc->rmb_dma_addr);
struct smc_link_group *lgr = conn->lgr;
u32 rkey = ntohl(clc->rmb_rkey);
int i;
for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
if ((lgr->rtokens[i][SMC_SINGLE_LINK].rkey == rkey) &&
(lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr == dma_addr) &&
test_bit(i, lgr->rtokens_used_mask)) {
conn->rtoken_idx = i;
return 0;
}
}
conn->rtoken_idx = smc_rmb_reserve_rtoken_idx(lgr);
if (conn->rtoken_idx < 0)
return conn->rtoken_idx;
lgr->rtokens[conn->rtoken_idx][SMC_SINGLE_LINK].rkey = rkey;
lgr->rtokens[conn->rtoken_idx][SMC_SINGLE_LINK].dma_addr = dma_addr;
return 0;
}