linux/net/smc/smc_cdc.h

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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
*
* Connection Data Control (CDC)
*
* Copyright IBM Corp. 2016
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
*/
#ifndef SMC_CDC_H
#define SMC_CDC_H
#include <linux/kernel.h> /* max_t */
#include <linux/atomic.h>
#include <linux/in.h>
#include <linux/compiler.h>
#include "smc.h"
#include "smc_core.h"
#include "smc_wr.h"
#define SMC_CDC_MSG_TYPE 0xFE
/* in network byte order */
union smc_cdc_cursor { /* SMC cursor */
struct {
__be16 reserved;
__be16 wrap;
__be32 count;
};
#ifdef KERNEL_HAS_ATOMIC64
atomic64_t acurs; /* for atomic processing */
#else
u64 acurs; /* for atomic processing */
#endif
} __aligned(8);
/* in network byte order */
struct smc_cdc_msg {
struct smc_wr_rx_hdr common; /* .type = 0xFE */
u8 len; /* 44 */
__be16 seqno;
__be32 token;
union smc_cdc_cursor prod;
union smc_cdc_cursor cons; /* piggy backed "ack" */
struct smc_cdc_producer_flags prod_flags;
struct smc_cdc_conn_state_flags conn_state_flags;
u8 reserved[18];
};
/* SMC-D cursor format */
union smcd_cdc_cursor {
struct {
u16 wrap;
u32 count;
struct smc_cdc_producer_flags prod_flags;
struct smc_cdc_conn_state_flags conn_state_flags;
} __packed;
#ifdef KERNEL_HAS_ATOMIC64
atomic64_t acurs; /* for atomic processing */
#else
u64 acurs; /* for atomic processing */
#endif
} __aligned(8);
/* CDC message for SMC-D */
struct smcd_cdc_msg {
struct smc_wr_rx_hdr common; /* Type = 0xFE */
u8 res1[7];
union smcd_cdc_cursor prod;
union smcd_cdc_cursor cons;
u8 res3[8];
} __aligned(8);
static inline bool smc_cdc_rxed_any_close(struct smc_connection *conn)
{
return conn->local_rx_ctrl.conn_state_flags.peer_conn_abort ||
conn->local_rx_ctrl.conn_state_flags.peer_conn_closed;
}
static inline bool smc_cdc_rxed_any_close_or_senddone(
struct smc_connection *conn)
{
return smc_cdc_rxed_any_close(conn) ||
conn->local_rx_ctrl.conn_state_flags.peer_done_writing;
}
static inline void smc_curs_add(int size, union smc_host_cursor *curs,
int value)
{
curs->count += value;
if (curs->count >= size) {
curs->wrap++;
curs->count -= size;
}
}
/* Copy cursor src into tgt */
static inline void smc_curs_copy(union smc_host_cursor *tgt,
union smc_host_cursor *src,
struct smc_connection *conn)
{
#ifndef KERNEL_HAS_ATOMIC64
unsigned long flags;
spin_lock_irqsave(&conn->acurs_lock, flags);
tgt->acurs = src->acurs;
spin_unlock_irqrestore(&conn->acurs_lock, flags);
#else
atomic64_set(&tgt->acurs, atomic64_read(&src->acurs));
#endif
}
static inline void smc_curs_copy_net(union smc_cdc_cursor *tgt,
union smc_cdc_cursor *src,
struct smc_connection *conn)
{
#ifndef KERNEL_HAS_ATOMIC64
unsigned long flags;
spin_lock_irqsave(&conn->acurs_lock, flags);
tgt->acurs = src->acurs;
spin_unlock_irqrestore(&conn->acurs_lock, flags);
#else
atomic64_set(&tgt->acurs, atomic64_read(&src->acurs));
#endif
}
static inline void smcd_curs_copy(union smcd_cdc_cursor *tgt,
union smcd_cdc_cursor *src,
struct smc_connection *conn)
{
#ifndef KERNEL_HAS_ATOMIC64
unsigned long flags;
spin_lock_irqsave(&conn->acurs_lock, flags);
tgt->acurs = src->acurs;
spin_unlock_irqrestore(&conn->acurs_lock, flags);
#else
atomic64_set(&tgt->acurs, atomic64_read(&src->acurs));
#endif
}
/* calculate cursor difference between old and new, where old <= new and
* difference cannot exceed size
*/
static inline int smc_curs_diff(unsigned int size,
union smc_host_cursor *old,
union smc_host_cursor *new)
{
if (old->wrap != new->wrap)
return max_t(int, 0,
((size - old->count) + new->count));
return max_t(int, 0, (new->count - old->count));
}
/* calculate cursor difference between old and new - returns negative
* value in case old > new
*/
static inline int smc_curs_comp(unsigned int size,
union smc_host_cursor *old,
union smc_host_cursor *new)
{
if (old->wrap > new->wrap ||
(old->wrap == new->wrap && old->count > new->count))
return -smc_curs_diff(size, new, old);
return smc_curs_diff(size, old, new);
}
/* calculate cursor difference between old and new, where old <= new and
* difference may exceed size
*/
static inline int smc_curs_diff_large(unsigned int size,
union smc_host_cursor *old,
union smc_host_cursor *new)
{
if (old->wrap < new->wrap)
return min_t(int,
(size - old->count) + new->count +
(new->wrap - old->wrap - 1) * size,
size);
if (old->wrap > new->wrap) /* wrap has switched from 0xffff to 0x0000 */
return min_t(int,
(size - old->count) + new->count +
(new->wrap + 0xffff - old->wrap) * size,
size);
return max_t(int, 0, (new->count - old->count));
}
static inline void smc_host_cursor_to_cdc(union smc_cdc_cursor *peer,
union smc_host_cursor *local,
union smc_host_cursor *save,
struct smc_connection *conn)
{
smc_curs_copy(save, local, conn);
peer->count = htonl(save->count);
peer->wrap = htons(save->wrap);
/* peer->reserved = htons(0); must be ensured by caller */
}
static inline void smc_host_msg_to_cdc(struct smc_cdc_msg *peer,
struct smc_connection *conn,
union smc_host_cursor *save)
{
struct smc_host_cdc_msg *local = &conn->local_tx_ctrl;
peer->common.type = local->common.type;
peer->len = local->len;
peer->seqno = htons(local->seqno);
peer->token = htonl(local->token);
smc_host_cursor_to_cdc(&peer->prod, &local->prod, save, conn);
smc_host_cursor_to_cdc(&peer->cons, &local->cons, save, conn);
peer->prod_flags = local->prod_flags;
peer->conn_state_flags = local->conn_state_flags;
}
static inline void smc_cdc_cursor_to_host(union smc_host_cursor *local,
union smc_cdc_cursor *peer,
struct smc_connection *conn)
{
union smc_host_cursor temp, old;
union smc_cdc_cursor net;
smc_curs_copy(&old, local, conn);
smc_curs_copy_net(&net, peer, conn);
temp.count = ntohl(net.count);
temp.wrap = ntohs(net.wrap);
if ((old.wrap > temp.wrap) && temp.wrap)
return;
if ((old.wrap == temp.wrap) &&
(old.count > temp.count))
return;
smc_curs_copy(local, &temp, conn);
}
static inline void smcr_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smc_cdc_msg *peer,
struct smc_connection *conn)
{
local->common.type = peer->common.type;
local->len = peer->len;
local->seqno = ntohs(peer->seqno);
local->token = ntohl(peer->token);
smc_cdc_cursor_to_host(&local->prod, &peer->prod, conn);
smc_cdc_cursor_to_host(&local->cons, &peer->cons, conn);
local->prod_flags = peer->prod_flags;
local->conn_state_flags = peer->conn_state_flags;
}
static inline void smcd_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smcd_cdc_msg *peer,
struct smc_connection *conn)
{
union smc_host_cursor temp;
temp.wrap = peer->prod.wrap;
temp.count = peer->prod.count;
smc_curs_copy(&local->prod, &temp, conn);
temp.wrap = peer->cons.wrap;
temp.count = peer->cons.count;
smc_curs_copy(&local->cons, &temp, conn);
local->prod_flags = peer->cons.prod_flags;
local->conn_state_flags = peer->cons.conn_state_flags;
}
static inline void smc_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smc_cdc_msg *peer,
struct smc_connection *conn)
{
if (conn->lgr->is_smcd)
smcd_cdc_msg_to_host(local, (struct smcd_cdc_msg *)peer, conn);
else
smcr_cdc_msg_to_host(local, peer, conn);
}
struct smc_cdc_tx_pend {
struct smc_connection *conn; /* socket connection */
union smc_host_cursor cursor; /* tx sndbuf cursor sent */
union smc_host_cursor p_cursor; /* rx RMBE cursor produced */
u16 ctrl_seq; /* conn. tx sequence # */
};
int smc_cdc_get_free_slot(struct smc_connection *conn,
struct smc_link *link,
struct smc_wr_buf **wr_buf,
struct smc_rdma_wr **wr_rdma_buf,
struct smc_cdc_tx_pend **pend);
net/smc: fix kernel panic caused by race of smc_sock A crash occurs when smc_cdc_tx_handler() tries to access smc_sock but smc_release() has already freed it. [ 4570.695099] BUG: unable to handle page fault for address: 000000002eae9e88 [ 4570.696048] #PF: supervisor write access in kernel mode [ 4570.696728] #PF: error_code(0x0002) - not-present page [ 4570.697401] PGD 0 P4D 0 [ 4570.697716] Oops: 0002 [#1] PREEMPT SMP NOPTI [ 4570.698228] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.16.0-rc4+ #111 [ 4570.699013] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 8c24b4c 04/0 [ 4570.699933] RIP: 0010:_raw_spin_lock+0x1a/0x30 <...> [ 4570.711446] Call Trace: [ 4570.711746] <IRQ> [ 4570.711992] smc_cdc_tx_handler+0x41/0xc0 [ 4570.712470] smc_wr_tx_tasklet_fn+0x213/0x560 [ 4570.712981] ? smc_cdc_tx_dismisser+0x10/0x10 [ 4570.713489] tasklet_action_common.isra.17+0x66/0x140 [ 4570.714083] __do_softirq+0x123/0x2f4 [ 4570.714521] irq_exit_rcu+0xc4/0xf0 [ 4570.714934] common_interrupt+0xba/0xe0 Though smc_cdc_tx_handler() checked the existence of smc connection, smc_release() may have already dismissed and released the smc socket before smc_cdc_tx_handler() further visits it. smc_cdc_tx_handler() |smc_release() if (!conn) | | |smc_cdc_tx_dismiss_slots() | smc_cdc_tx_dismisser() | |sock_put(&smc->sk) <- last sock_put, | smc_sock freed bh_lock_sock(&smc->sk) (panic) | To make sure we won't receive any CDC messages after we free the smc_sock, add a refcount on the smc_connection for inflight CDC message(posted to the QP but haven't received related CQE), and don't release the smc_connection until all the inflight CDC messages haven been done, for both success or failed ones. Using refcount on CDC messages brings another problem: when the link is going to be destroyed, smcr_link_clear() will reset the QP, which then remove all the pending CQEs related to the QP in the CQ. To make sure all the CQEs will always come back so the refcount on the smc_connection can always reach 0, smc_ib_modify_qp_reset() was replaced by smc_ib_modify_qp_error(). And remove the timeout in smc_wr_tx_wait_no_pending_sends() since we need to wait for all pending WQEs done, or we may encounter use-after- free when handling CQEs. For IB device removal routine, we need to wait for all the QPs on that device been destroyed before we can destroy CQs on the device, or the refcount on smc_connection won't reach 0 and smc_sock cannot be released. Fixes: 5f08318f617b ("smc: connection data control (CDC)") Reported-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: Dust Li <dust.li@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-28 09:03:25 +00:00
void smc_cdc_wait_pend_tx_wr(struct smc_connection *conn);
int smc_cdc_msg_send(struct smc_connection *conn, struct smc_wr_buf *wr_buf,
struct smc_cdc_tx_pend *pend);
int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn);
int smcd_cdc_msg_send(struct smc_connection *conn);
int smcr_cdc_msg_send_validation(struct smc_connection *conn,
struct smc_cdc_tx_pend *pend,
struct smc_wr_buf *wr_buf);
int smc_cdc_init(void) __init;
void smcd_cdc_rx_init(struct smc_connection *conn);
#endif /* SMC_CDC_H */