linux-brain/net/smc/smc_rx.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 23:07:57 +09:00
// SPDX-License-Identifier: GPL-2.0
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* Manage RMBE
* copy new RMBE data into user space
*
* Copyright IBM Corp. 2016
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
*/
#include <linux/net.h>
#include <linux/rcupdate.h>
sched/headers: Move task_struct::signal and task_struct::sighand types and accessors into <linux/sched/signal.h> task_struct::signal and task_struct::sighand are pointers, which would normally make it straightforward to not define those types in sched.h. That is not so, because the types are accompanied by a myriad of APIs (macros and inline functions) that dereference them. Split the types and the APIs out of sched.h and move them into a new header, <linux/sched/signal.h>. With this change sched.h does not know about 'struct signal' and 'struct sighand' anymore, trying to put accessors into sched.h as a test fails the following way: ./include/linux/sched.h: In function ‘test_signal_types’: ./include/linux/sched.h:2461:18: error: dereferencing pointer to incomplete type ‘struct signal_struct’ ^ This reduces the size and complexity of sched.h significantly. Update all headers and .c code that relied on getting the signal handling functionality from <linux/sched.h> to include <linux/sched/signal.h>. The list of affected files in the preparatory patch was partly generated by grepping for the APIs, and partly by doing coverage build testing, both all[yes|mod|def|no]config builds on 64-bit and 32-bit x86, and an array of cross-architecture builds. Nevertheless some (trivial) build breakage is still expected related to rare Kconfig combinations and in-flight patches to various kernel code, but most of it should be handled by this patch. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-02 16:35:14 +09:00
#include <linux/sched/signal.h>
#include <net/sock.h>
#include "smc.h"
#include "smc_core.h"
#include "smc_cdc.h"
#include "smc_tx.h" /* smc_tx_consumer_update() */
#include "smc_rx.h"
/* callback implementation to wakeup consumers blocked with smc_rx_wait().
* indirectly called by smc_cdc_msg_recv_action().
*/
static void smc_rx_wake_up(struct sock *sk)
{
struct socket_wq *wq;
/* derived from sock_def_readable() */
/* called already in smc_listen_work() */
rcu_read_lock();
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
EPOLLRDNORM | EPOLLRDBAND);
sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
(sk->sk_state == SMC_CLOSED))
sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP);
rcu_read_unlock();
}
/* Update consumer cursor
* @conn connection to update
* @cons consumer cursor
* @len number of Bytes consumed
* Returns:
* 1 if we should end our receive, 0 otherwise
*/
static int smc_rx_update_consumer(struct smc_sock *smc,
union smc_host_cursor cons, size_t len)
{
struct smc_connection *conn = &smc->conn;
struct sock *sk = &smc->sk;
bool force = false;
int diff, rc = 0;
smc_curs_add(conn->rmb_desc->len, &cons, len);
/* did we process urgent data? */
if (conn->urg_state == SMC_URG_VALID || conn->urg_rx_skip_pend) {
diff = smc_curs_comp(conn->rmb_desc->len, &cons,
&conn->urg_curs);
if (sock_flag(sk, SOCK_URGINLINE)) {
if (diff == 0) {
force = true;
rc = 1;
conn->urg_state = SMC_URG_READ;
}
} else {
if (diff == 1) {
/* skip urgent byte */
force = true;
smc_curs_add(conn->rmb_desc->len, &cons, 1);
conn->urg_rx_skip_pend = false;
} else if (diff < -1)
/* we read past urgent byte */
conn->urg_state = SMC_URG_READ;
}
}
smc_curs_copy(&conn->local_tx_ctrl.cons, &cons, conn);
/* send consumer cursor update if required */
/* similar to advertising new TCP rcv_wnd if required */
smc_tx_consumer_update(conn, force);
return rc;
}
static void smc_rx_update_cons(struct smc_sock *smc, size_t len)
{
struct smc_connection *conn = &smc->conn;
union smc_host_cursor cons;
smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
smc_rx_update_consumer(smc, cons, len);
}
struct smc_spd_priv {
struct smc_sock *smc;
size_t len;
};
static void smc_rx_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct smc_spd_priv *priv = (struct smc_spd_priv *)buf->private;
struct smc_sock *smc = priv->smc;
struct smc_connection *conn;
struct sock *sk = &smc->sk;
if (sk->sk_state == SMC_CLOSED ||
sk->sk_state == SMC_PEERFINCLOSEWAIT ||
sk->sk_state == SMC_APPFINCLOSEWAIT)
goto out;
conn = &smc->conn;
lock_sock(sk);
smc_rx_update_cons(smc, priv->len);
release_sock(sk);
if (atomic_sub_and_test(priv->len, &conn->splice_pending))
smc_rx_wake_up(sk);
out:
kfree(priv);
put_page(buf->page);
sock_put(sk);
}
static int smc_rx_pipe_buf_nosteal(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
return 1;
}
static const struct pipe_buf_operations smc_pipe_ops = {
.confirm = generic_pipe_buf_confirm,
.release = smc_rx_pipe_buf_release,
.steal = smc_rx_pipe_buf_nosteal,
.get = generic_pipe_buf_get
};
static void smc_rx_spd_release(struct splice_pipe_desc *spd,
unsigned int i)
{
put_page(spd->pages[i]);
}
static int smc_rx_splice(struct pipe_inode_info *pipe, char *src, size_t len,
struct smc_sock *smc)
{
struct splice_pipe_desc spd;
struct partial_page partial;
struct smc_spd_priv *priv;
int bytes;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->len = len;
priv->smc = smc;
partial.offset = src - (char *)smc->conn.rmb_desc->cpu_addr;
partial.len = len;
partial.private = (unsigned long)priv;
spd.nr_pages_max = 1;
spd.nr_pages = 1;
spd.pages = &smc->conn.rmb_desc->pages;
spd.partial = &partial;
spd.ops = &smc_pipe_ops;
spd.spd_release = smc_rx_spd_release;
bytes = splice_to_pipe(pipe, &spd);
if (bytes > 0) {
sock_hold(&smc->sk);
get_page(smc->conn.rmb_desc->pages);
atomic_add(bytes, &smc->conn.splice_pending);
}
return bytes;
}
static int smc_rx_data_available_and_no_splice_pend(struct smc_connection *conn)
{
return atomic_read(&conn->bytes_to_rcv) &&
!atomic_read(&conn->splice_pending);
}
/* blocks rcvbuf consumer until >=len bytes available or timeout or interrupted
* @smc smc socket
* @timeo pointer to max seconds to wait, pointer to value 0 for no timeout
* @fcrit add'l criterion to evaluate as function pointer
* Returns:
* 1 if at least 1 byte available in rcvbuf or if socket error/shutdown.
* 0 otherwise (nothing in rcvbuf nor timeout, e.g. interrupted).
*/
int smc_rx_wait(struct smc_sock *smc, long *timeo,
int (*fcrit)(struct smc_connection *conn))
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct smc_connection *conn = &smc->conn;
struct sock *sk = &smc->sk;
int rc;
if (fcrit(conn))
return 1;
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
add_wait_queue(sk_sleep(sk), &wait);
rc = sk_wait_event(sk, timeo,
sk->sk_err ||
sk->sk_shutdown & RCV_SHUTDOWN ||
fcrit(conn),
&wait);
remove_wait_queue(sk_sleep(sk), &wait);
sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
return rc;
}
static int smc_rx_recv_urg(struct smc_sock *smc, struct msghdr *msg, int len,
int flags)
{
struct smc_connection *conn = &smc->conn;
union smc_host_cursor cons;
struct sock *sk = &smc->sk;
int rc = 0;
if (sock_flag(sk, SOCK_URGINLINE) ||
!(conn->urg_state == SMC_URG_VALID) ||
conn->urg_state == SMC_URG_READ)
return -EINVAL;
if (conn->urg_state == SMC_URG_VALID) {
if (!(flags & MSG_PEEK))
smc->conn.urg_state = SMC_URG_READ;
msg->msg_flags |= MSG_OOB;
if (len > 0) {
if (!(flags & MSG_TRUNC))
rc = memcpy_to_msg(msg, &conn->urg_rx_byte, 1);
len = 1;
smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
if (smc_curs_diff(conn->rmb_desc->len, &cons,
&conn->urg_curs) > 1)
conn->urg_rx_skip_pend = true;
/* Urgent Byte was already accounted for, but trigger
* skipping the urgent byte in non-inline case
*/
if (!(flags & MSG_PEEK))
smc_rx_update_consumer(smc, cons, 0);
} else {
msg->msg_flags |= MSG_TRUNC;
}
return rc ? -EFAULT : len;
}
if (sk->sk_state == SMC_CLOSED || sk->sk_shutdown & RCV_SHUTDOWN)
return 0;
return -EAGAIN;
}
static bool smc_rx_recvmsg_data_available(struct smc_sock *smc)
{
struct smc_connection *conn = &smc->conn;
if (smc_rx_data_available(conn))
return true;
else if (conn->urg_state == SMC_URG_VALID)
/* we received a single urgent Byte - skip */
smc_rx_update_cons(smc, 0);
return false;
}
/* smc_rx_recvmsg - receive data from RMBE
* @msg: copy data to receive buffer
* @pipe: copy data to pipe if set - indicates splice() call
*
* rcvbuf consumer: main API called by socket layer.
* Called under sk lock.
*/
int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg,
struct pipe_inode_info *pipe, size_t len, int flags)
{
size_t copylen, read_done = 0, read_remaining = len;
size_t chunk_len, chunk_off, chunk_len_sum;
struct smc_connection *conn = &smc->conn;
int (*func)(struct smc_connection *conn);
union smc_host_cursor cons;
int readable, chunk;
char *rcvbuf_base;
struct sock *sk;
int splbytes;
long timeo;
int target; /* Read at least these many bytes */
int rc;
if (unlikely(flags & MSG_ERRQUEUE))
return -EINVAL; /* future work for sk.sk_family == AF_SMC */
sk = &smc->sk;
if (sk->sk_state == SMC_LISTEN)
return -ENOTCONN;
if (flags & MSG_OOB)
return smc_rx_recv_urg(smc, msg, len, flags);
timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
/* we currently use 1 RMBE per RMB, so RMBE == RMB base addr */
rcvbuf_base = conn->rx_off + conn->rmb_desc->cpu_addr;
do { /* while (read_remaining) */
if (read_done >= target || (pipe && read_done))
break;
if (smc_rx_recvmsg_data_available(smc))
goto copy;
if (sk->sk_shutdown & RCV_SHUTDOWN ||
conn->local_tx_ctrl.conn_state_flags.peer_conn_abort) {
/* smc_cdc_msg_recv_action() could have run after
* above smc_rx_recvmsg_data_available()
*/
if (smc_rx_recvmsg_data_available(smc))
goto copy;
break;
}
if (read_done) {
if (sk->sk_err ||
sk->sk_state == SMC_CLOSED ||
!timeo ||
signal_pending(current))
break;
} else {
if (sk->sk_err) {
read_done = sock_error(sk);
break;
}
if (sk->sk_state == SMC_CLOSED) {
if (!sock_flag(sk, SOCK_DONE)) {
/* This occurs when user tries to read
* from never connected socket.
*/
read_done = -ENOTCONN;
break;
}
break;
}
if (signal_pending(current)) {
read_done = sock_intr_errno(timeo);
break;
}
if (!timeo)
return -EAGAIN;
}
if (!smc_rx_data_available(conn)) {
smc_rx_wait(smc, &timeo, smc_rx_data_available);
continue;
}
copy:
/* initialize variables for 1st iteration of subsequent loop */
/* could be just 1 byte, even after waiting on data above */
readable = atomic_read(&conn->bytes_to_rcv);
splbytes = atomic_read(&conn->splice_pending);
if (!readable || (msg && splbytes)) {
if (splbytes)
func = smc_rx_data_available_and_no_splice_pend;
else
func = smc_rx_data_available;
smc_rx_wait(smc, &timeo, func);
continue;
}
smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
/* subsequent splice() calls pick up where previous left */
if (splbytes)
smc_curs_add(conn->rmb_desc->len, &cons, splbytes);
if (conn->urg_state == SMC_URG_VALID &&
sock_flag(&smc->sk, SOCK_URGINLINE) &&
readable > 1)
readable--; /* always stop at urgent Byte */
/* not more than what user space asked for */
copylen = min_t(size_t, read_remaining, readable);
/* determine chunks where to read from rcvbuf */
/* either unwrapped case, or 1st chunk of wrapped case */
chunk_len = min_t(size_t, copylen, conn->rmb_desc->len -
cons.count);
chunk_len_sum = chunk_len;
chunk_off = cons.count;
smc_rmb_sync_sg_for_cpu(conn);
for (chunk = 0; chunk < 2; chunk++) {
if (!(flags & MSG_TRUNC)) {
if (msg) {
rc = memcpy_to_msg(msg, rcvbuf_base +
chunk_off,
chunk_len);
} else {
rc = smc_rx_splice(pipe, rcvbuf_base +
chunk_off, chunk_len,
smc);
}
if (rc < 0) {
if (!read_done)
read_done = -EFAULT;
smc_rmb_sync_sg_for_device(conn);
goto out;
}
}
read_remaining -= chunk_len;
read_done += chunk_len;
if (chunk_len_sum == copylen)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
chunk_len = copylen - chunk_len; /* remainder */
chunk_len_sum += chunk_len;
chunk_off = 0; /* modulo offset in recv ring buffer */
}
smc_rmb_sync_sg_for_device(conn);
/* update cursors */
if (!(flags & MSG_PEEK)) {
/* increased in recv tasklet smc_cdc_msg_rcv() */
smp_mb__before_atomic();
atomic_sub(copylen, &conn->bytes_to_rcv);
/* guarantee 0 <= bytes_to_rcv <= rmb_desc->len */
smp_mb__after_atomic();
if (msg && smc_rx_update_consumer(smc, cons, copylen))
goto out;
}
} while (read_remaining);
out:
return read_done;
}
/* Initialize receive properties on connection establishment. NB: not __init! */
void smc_rx_init(struct smc_sock *smc)
{
smc->sk.sk_data_ready = smc_rx_wake_up;
atomic_set(&smc->conn.splice_pending, 0);
smc->conn.urg_state = SMC_URG_READ;
}