Release 4.7 fs/pipe.c
/*
* linux/fs/pipe.c
*
* Copyright (C) 1991, 1992, 1999 Linus Torvalds
*/
#include <linux/mm.h>
#include <linux/file.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/log2.h>
#include <linux/mount.h>
#include <linux/magic.h>
#include <linux/pipe_fs_i.h>
#include <linux/uio.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/audit.h>
#include <linux/syscalls.h>
#include <linux/fcntl.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include "internal.h"
/*
* The max size that a non-root user is allowed to grow the pipe. Can
* be set by root in /proc/sys/fs/pipe-max-size
*/
unsigned int pipe_max_size = 1048576;
/*
* Minimum pipe size, as required by POSIX
*/
unsigned int pipe_min_size = PAGE_SIZE;
/* Maximum allocatable pages per user. Hard limit is unset by default, soft
* matches default values.
*/
unsigned long pipe_user_pages_hard;
unsigned long pipe_user_pages_soft = PIPE_DEF_BUFFERS * INR_OPEN_CUR;
/*
* We use a start+len construction, which provides full use of the
* allocated memory.
* -- Florian Coosmann (FGC)
*
* Reads with count = 0 should always return 0.
* -- Julian Bradfield 1999-06-07.
*
* FIFOs and Pipes now generate SIGIO for both readers and writers.
* -- Jeremy Elson <jelson@circlemud.org> 2001-08-16
*
* pipe_read & write cleanup
* -- Manfred Spraul <manfred@colorfullife.com> 2002-05-09
*/
static void pipe_lock_nested(struct pipe_inode_info *pipe, int subclass)
{
if (pipe->files)
mutex_lock_nested(&pipe->mutex, subclass);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
miklos szeredi | miklos szeredi | 28 | 93.33% | 1 | 33.33% |
al viro | al viro | 2 | 6.67% | 2 | 66.67% |
| Total | 30 | 100.00% | 3 | 100.00% |
void pipe_lock(struct pipe_inode_info *pipe)
{
/*
* pipe_lock() nests non-pipe inode locks (for writing to a file)
*/
pipe_lock_nested(pipe, I_MUTEX_PARENT);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
miklos szeredi | miklos szeredi | 18 | 100.00% | 1 | 100.00% |
| Total | 18 | 100.00% | 1 | 100.00% |
EXPORT_SYMBOL(pipe_lock);
void pipe_unlock(struct pipe_inode_info *pipe)
{
if (pipe->files)
mutex_unlock(&pipe->mutex);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
miklos szeredi | miklos szeredi | 22 | 91.67% | 1 | 33.33% |
al viro | al viro | 2 | 8.33% | 2 | 66.67% |
| Total | 24 | 100.00% | 3 | 100.00% |
EXPORT_SYMBOL(pipe_unlock);
static inline void __pipe_lock(struct pipe_inode_info *pipe)
{
mutex_lock_nested(&pipe->mutex, I_MUTEX_PARENT);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
al viro | al viro | 22 | 100.00% | 1 | 100.00% |
| Total | 22 | 100.00% | 1 | 100.00% |
static inline void __pipe_unlock(struct pipe_inode_info *pipe)
{
mutex_unlock(&pipe->mutex);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
al viro | al viro | 20 | 100.00% | 1 | 100.00% |
| Total | 20 | 100.00% | 1 | 100.00% |
void pipe_double_lock(struct pipe_inode_info *pipe1,
struct pipe_inode_info *pipe2)
{
BUG_ON(pipe1 == pipe2);
if (pipe1 < pipe2) {
pipe_lock_nested(pipe1, I_MUTEX_PARENT);
pipe_lock_nested(pipe2, I_MUTEX_CHILD);
} else {
pipe_lock_nested(pipe2, I_MUTEX_PARENT);
pipe_lock_nested(pipe1, I_MUTEX_CHILD);
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
miklos szeredi | miklos szeredi | 59 | 96.72% | 1 | 50.00% |
peter zijlstra | peter zijlstra | 2 | 3.28% | 1 | 50.00% |
| Total | 61 | 100.00% | 2 | 100.00% |
/* Drop the inode semaphore and wait for a pipe event, atomically */
void pipe_wait(struct pipe_inode_info *pipe)
{
DEFINE_WAIT(wait);
/*
* Pipes are system-local resources, so sleeping on them
* is considered a noninteractive wait:
*/
prepare_to_wait(&pipe->wait, &wait, TASK_INTERRUPTIBLE);
pipe_unlock(pipe);
schedule();
finish_wait(&pipe->wait, &wait);
pipe_lock(pipe);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
pre-git | pre-git | 33 | 62.26% | 2 | 33.33% |
ingo molnar | ingo molnar | 13 | 24.53% | 2 | 33.33% |
andrew morton | andrew morton | 5 | 9.43% | 1 | 16.67% |
miklos szeredi | miklos szeredi | 2 | 3.77% | 1 | 16.67% |
| Total | 53 | 100.00% | 6 | 100.00% |
static void anon_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct page *page = buf->page;
/*
* If nobody else uses this page, and we don't already have a
* temporary page, let's keep track of it as a one-deep
* allocation cache. (Otherwise just release our reference to it)
*/
if (page_count(page) == 1 && !pipe->tmp_page)
pipe->tmp_page = page;
else
put_page(page);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 34 | 65.38% | 2 | 33.33% |
jens axboe | jens axboe | 12 | 23.08% | 1 | 16.67% |
ingo molnar | ingo molnar | 5 | 9.62% | 2 | 33.33% |
kirill a. shutemov | kirill a. shutemov | 1 | 1.92% | 1 | 16.67% |
| Total | 52 | 100.00% | 6 | 100.00% |
/**
* generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer
* @pipe: the pipe that the buffer belongs to
* @buf: the buffer to attempt to steal
*
* Description:
* This function attempts to steal the &struct page attached to
* @buf. If successful, this function returns 0 and returns with
* the page locked. The caller may then reuse the page for whatever
* he wishes; the typical use is insertion into a different file
* page cache.
*/
int generic_pipe_buf_steal(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct page *page = buf->page;
/*
* A reference of one is golden, that means that the owner of this
* page is the only one holding a reference to it. lock the page
* and return OK.
*/
if (page_count(page) == 1) {
lock_page(page);
return 0;
}
return 1;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
jens axboe | jens axboe | 46 | 97.87% | 4 | 80.00% |
ingo molnar | ingo molnar | 1 | 2.13% | 1 | 20.00% |
| Total | 47 | 100.00% | 5 | 100.00% |
EXPORT_SYMBOL(generic_pipe_buf_steal);
/**
* generic_pipe_buf_get - get a reference to a &struct pipe_buffer
* @pipe: the pipe that the buffer belongs to
* @buf: the buffer to get a reference to
*
* Description:
* This function grabs an extra reference to @buf. It's used in
* in the tee() system call, when we duplicate the buffers in one
* pipe into another.
*/
void generic_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf)
{
get_page(buf->page);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
jens axboe | jens axboe | 21 | 95.45% | 3 | 75.00% |
kirill a. shutemov | kirill a. shutemov | 1 | 4.55% | 1 | 25.00% |
| Total | 22 | 100.00% | 4 | 100.00% |
EXPORT_SYMBOL(generic_pipe_buf_get);
/**
* generic_pipe_buf_confirm - verify contents of the pipe buffer
* @info: the pipe that the buffer belongs to
* @buf: the buffer to confirm
*
* Description:
* This function does nothing, because the generic pipe code uses
* pages that are always good when inserted into the pipe.
*/
int generic_pipe_buf_confirm(struct pipe_inode_info *info,
struct pipe_buffer *buf)
{
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
jens axboe | jens axboe | 18 | 100.00% | 2 | 100.00% |
| Total | 18 | 100.00% | 2 | 100.00% |
EXPORT_SYMBOL(generic_pipe_buf_confirm);
/**
* generic_pipe_buf_release - put a reference to a &struct pipe_buffer
* @pipe: the pipe that the buffer belongs to
* @buf: the buffer to put a reference to
*
* Description:
* This function releases a reference to @buf.
*/
void generic_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
put_page(buf->page);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
miklos szeredi | miklos szeredi | 21 | 95.45% | 1 | 50.00% |
kirill a. shutemov | kirill a. shutemov | 1 | 4.55% | 1 | 50.00% |
| Total | 22 | 100.00% | 2 | 100.00% |
EXPORT_SYMBOL(generic_pipe_buf_release);
static const struct pipe_buf_operations anon_pipe_buf_ops = {
.can_merge = 1,
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = generic_pipe_buf_steal,
.get = generic_pipe_buf_get,
};
static const struct pipe_buf_operations packet_pipe_buf_ops = {
.can_merge = 0,
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = generic_pipe_buf_steal,
.get = generic_pipe_buf_get,
};
static ssize_t
pipe_read(struct kiocb *iocb, struct iov_iter *to)
{
size_t total_len = iov_iter_count(to);
struct file *filp = iocb->ki_filp;
struct pipe_inode_info *pipe = filp->private_data;
int do_wakeup;
ssize_t ret;
/* Null read succeeds. */
if (unlikely(total_len == 0))
return 0;
do_wakeup = 0;
ret = 0;
__pipe_lock(pipe);
for (;;) {
int bufs = pipe->nrbufs;
if (bufs) {
int curbuf = pipe->curbuf;
struct pipe_buffer *buf = pipe->bufs + curbuf;
const struct pipe_buf_operations *ops = buf->ops;
size_t chars = buf->len;
size_t written;
int error;
if (chars > total_len)
chars = total_len;
error = ops->confirm(pipe, buf);
if (error) {
if (!ret)
ret = error;
break;
}
written = copy_page_to_iter(buf->page, buf->offset, chars, to);
if (unlikely(written < chars)) {
if (!ret)
ret = -EFAULT;
break;
}
ret += chars;
buf->offset += chars;
buf->len -= chars;
/* Was it a packet buffer? Clean up and exit */
if (buf->flags & PIPE_BUF_FLAG_PACKET) {
total_len = chars;
buf->len = 0;
}
if (!buf->len) {
buf->ops = NULL;
ops->release(pipe, buf);
curbuf = (curbuf + 1) & (pipe->buffers - 1);
pipe->curbuf = curbuf;
pipe->nrbufs = --bufs;
do_wakeup = 1;
}
total_len -= chars;
if (!total_len)
break; /* common path: read succeeded */
}
if (bufs) /* More to do? */
continue;
if (!pipe->writers)
break;
if (!pipe->waiting_writers) {
/* syscall merging: Usually we must not sleep
* if O_NONBLOCK is set, or if we got some data.
* But if a writer sleeps in kernel space, then
* we can wait for that data without violating POSIX.
*/
if (ret)
break;
if (filp->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
break;
}
}
if (signal_pending(current)) {
if (!ret)
ret = -ERESTARTSYS;
break;
}
if (do_wakeup) {
wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}
pipe_wait(pipe);
}
__pipe_unlock(pipe);
/* Signal writers asynchronously that there is more room. */
if (do_wakeup) {
wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}
if (ret > 0)
file_accessed(filp);
return ret;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 128 | 27.47% | 5 | 12.50% |
manfred spraul | manfred spraul | 103 | 22.10% | 1 | 2.50% |
pre-git | pre-git | 101 | 21.67% | 13 | 32.50% |
al viro | al viro | 36 | 7.73% | 7 | 17.50% |
ingo molnar | ingo molnar | 32 | 6.87% | 3 | 7.50% |
jens axboe | jens axboe | 22 | 4.72% | 5 | 12.50% |
dave jones | dave jones | 16 | 3.43% | 1 | 2.50% |
badari pulavarty | badari pulavarty | 12 | 2.58% | 1 | 2.50% |
andrew morton | andrew morton | 7 | 1.50% | 1 | 2.50% |
davide libenzi | davide libenzi | 6 | 1.29% | 1 | 2.50% |
nicolas kaiser | nicolas kaiser | 2 | 0.43% | 1 | 2.50% |
eric dumazet | eric dumazet | 1 | 0.21% | 1 | 2.50% |
| Total | 466 | 100.00% | 40 | 100.00% |
static inline int is_packetized(struct file *file)
{
return (file->f_flags & O_DIRECT) != 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 23 | 100.00% | 1 | 100.00% |
| Total | 23 | 100.00% | 1 | 100.00% |
static ssize_t
pipe_write(struct kiocb *iocb, struct iov_iter *from)
{
struct file *filp = iocb->ki_filp;
struct pipe_inode_info *pipe = filp->private_data;
ssize_t ret = 0;
int do_wakeup = 0;
size_t total_len = iov_iter_count(from);
ssize_t chars;
/* Null write succeeds. */
if (unlikely(total_len == 0))
return 0;
__pipe_lock(pipe);
if (!pipe->readers) {
send_sig(SIGPIPE, current, 0);
ret = -EPIPE;
goto out;
}
/* We try to merge small writes */
chars = total_len & (PAGE_SIZE-1); /* size of the last buffer */
if (pipe->nrbufs && chars != 0) {
int lastbuf = (pipe->curbuf + pipe->nrbufs - 1) &
(pipe->buffers - 1);
struct pipe_buffer *buf = pipe->bufs + lastbuf;
const struct pipe_buf_operations *ops = buf->ops;
int offset = buf->offset + buf->len;
if (ops->can_merge && offset + chars <= PAGE_SIZE) {
ret = ops->confirm(pipe, buf);
if (ret)
goto out;
ret = copy_page_from_iter(buf->page, offset, chars, from);
if (unlikely(ret < chars)) {
ret = -EFAULT;
goto out;
}
do_wakeup = 1;
buf->len += ret;
if (!iov_iter_count(from))
goto out;
}
}
for (;;) {
int bufs;
if (!pipe->readers) {
send_sig(SIGPIPE, current, 0);
if (!ret)
ret = -EPIPE;
break;
}
bufs = pipe->nrbufs;
if (bufs < pipe->buffers) {
int newbuf = (pipe->curbuf + bufs) & (pipe->buffers-1);
struct pipe_buffer *buf = pipe->bufs + newbuf;
struct page *page = pipe->tmp_page;
int copied;
if (!page) {
page = alloc_page(GFP_HIGHUSER);
if (unlikely(!page)) {
ret = ret ? : -ENOMEM;
break;
}
pipe->tmp_page = page;
}
/* Always wake up, even if the copy fails. Otherwise
* we lock up (O_NONBLOCK-)readers that sleep due to
* syscall merging.
* FIXME! Is this really true?
*/
do_wakeup = 1;
copied = copy_page_from_iter(page, 0, PAGE_SIZE, from);
if (unlikely(copied < PAGE_SIZE && iov_iter_count(from))) {
if (!ret)
ret = -EFAULT;
break;
}
ret += copied;
/* Insert it into the buffer array */
buf->page = page;
buf->ops = &anon_pipe_buf_ops;
buf->offset = 0;
buf->len = copied;
buf->flags = 0;
if (is_packetized(filp)) {
buf->ops = &packet_pipe_buf_ops;
buf->flags = PIPE_BUF_FLAG_PACKET;
}
pipe->nrbufs = ++bufs;
pipe->tmp_page = NULL;
if (!iov_iter_count(from))
break;
}
if (bufs < pipe->buffers)
continue;
if (filp->f_flags & O_NONBLOCK) {
if (!ret)
ret = -EAGAIN;
break;
}
if (signal_pending(current)) {
if (!ret)
ret = -ERESTARTSYS;
break;
}
if (do_wakeup) {
wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
do_wakeup = 0;
}
pipe->waiting_writers++;
pipe_wait(pipe);
pipe->waiting_writers--;
}
out:
__pipe_unlock(pipe);
if (do_wakeup) {
wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
}
if (ret > 0 && sb_start_write_trylock(file_inode(filp)->i_sb)) {
int err = file_update_time(filp);
if (err)
ret = err;
sb_end_write(file_inode(filp)->i_sb);
}
return ret;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 240 | 33.85% | 6 | 13.64% |
manfred spraul | manfred spraul | 116 | 16.36% | 1 | 2.27% |
pre-git | pre-git | 74 | 10.44% | 13 | 29.55% |
al viro | al viro | 63 | 8.89% | 5 | 11.36% |
ingo molnar | ingo molnar | 43 | 6.06% | 3 | 6.82% |
jens axboe | jens axboe | 36 | 5.08% | 5 | 11.36% |
prasanna meda | prasanna meda | 23 | 3.24% | 1 | 2.27% |
andrea arcangeli | andrea arcangeli | 23 | 3.24% | 1 | 2.27% |
dmitriy monakhov | dmitriy monakhov | 20 | 2.82% | 1 | 2.27% |
andrew morton | andrew morton | 16 | 2.26% | 1 | 2.27% |
dave jones | dave jones | 16 | 2.26% | 1 | 2.27% |
josef bacik | josef bacik | 13 | 1.83% | 1 | 2.27% |
badari pulavarty | badari pulavarty | 12 | 1.69% | 1 | 2.27% |
davide libenzi | davide libenzi | 6 | 0.85% | 1 | 2.27% |
eric biggers | eric biggers | 5 | 0.71% | 1 | 2.27% |
christoph hellwig | christoph hellwig | 2 | 0.28% | 1 | 2.27% |
eric dumazet | eric dumazet | 1 | 0.14% | 1 | 2.27% |
| Total | 709 | 100.00% | 44 | 100.00% |
static long pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct pipe_inode_info *pipe = filp->private_data;
int count, buf, nrbufs;
switch (cmd) {
case FIONREAD:
__pipe_lock(pipe);
count = 0;
buf = pipe->curbuf;
nrbufs = pipe->nrbufs;
while (--nrbufs >= 0) {
count += pipe->bufs[buf].len;
buf = (buf+1) & (pipe->buffers - 1);
}
__pipe_unlock(pipe);
return put_user(count, (int __user *)arg);
default:
return -ENOIOCTLCMD;
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 67 | 54.03% | 2 | 16.67% |
pre-git | pre-git | 39 | 31.45% | 3 | 25.00% |
al viro | al viro | 8 | 6.45% | 3 | 25.00% |
ingo molnar | ingo molnar | 4 | 3.23% | 1 | 8.33% |
jens axboe | jens axboe | 3 | 2.42% | 1 | 8.33% |
andi kleen | andi kleen | 2 | 1.61% | 1 | 8.33% |
will deacon | will deacon | 1 | 0.81% | 1 | 8.33% |
| Total | 124 | 100.00% | 12 | 100.00% |
/* No kernel lock held - fine */
static unsigned int
pipe_poll(struct file *filp, poll_table *wait)
{
unsigned int mask;
struct pipe_inode_info *pipe = filp->private_data;
int nrbufs;
poll_wait(filp, &pipe->wait, wait);
/* Reading only -- no need for acquiring the semaphore. */
nrbufs = pipe->nrbufs;
mask = 0;
if (filp->f_mode & FMODE_READ) {
mask = (nrbufs > 0) ? POLLIN | POLLRDNORM : 0;
if (!pipe->writers && filp->f_version != pipe->w_counter)
mask |= POLLHUP;
}
if (filp->f_mode & FMODE_WRITE) {
mask |= (nrbufs < pipe->buffers) ? POLLOUT | POLLWRNORM : 0;
/*
* Most Unices do not set POLLERR for FIFOs but on Linux they
* behave exactly like pipes for poll().
*/
if (!pipe->readers)
mask |= POLLERR;
}
return mask;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
pre-git | pre-git | 63 | 45.32% | 8 | 50.00% |
linus torvalds | linus torvalds | 55 | 39.57% | 2 | 12.50% |
ingo molnar | ingo molnar | 14 | 10.07% | 2 | 12.50% |
jens axboe | jens axboe | 3 | 2.16% | 1 | 6.25% |
al viro | al viro | 3 | 2.16% | 2 | 12.50% |
pekka j enberg | pekka j enberg | 1 | 0.72% | 1 | 6.25% |
| Total | 139 | 100.00% | 16 | 100.00% |
static void put_pipe_info(struct inode *inode, struct pipe_inode_info *pipe)
{
int kill = 0;
spin_lock(&inode->i_lock);
if (!--pipe->files) {
inode->i_pipe = NULL;
kill = 1;
}
spin_unlock(&inode->i_lock);
if (kill)
free_pipe_info(pipe);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 66 | 100.00% | 1 | 100.00% |
| Total | 66 | 100.00% | 1 | 100.00% |
static int
pipe_release(struct inode *inode, struct file *file)
{
struct pipe_inode_info *pipe = file->private_data;
__pipe_lock(pipe);
if (file->f_mode & FMODE_READ)
pipe->readers--;
if (file->f_mode & FMODE_WRITE)
pipe->writers--;
if (pipe->readers || pipe->writers) {
wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM | POLLERR | POLLHUP);
kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}
__pipe_unlock(pipe);
put_pipe_info(inode, pipe);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
al viro | al viro | 36 | 28.35% | 3 | 23.08% |
ingo molnar | ingo molnar | 30 | 23.62% | 2 | 15.38% |
dave jones | dave jones | 23 | 18.11% | 1 | 7.69% |
pre-git | pre-git | 20 | 15.75% | 4 | 30.77% |
linus torvalds | linus torvalds | 13 | 10.24% | 2 | 15.38% |
davide libenzi | davide libenzi | 5 | 3.94% | 1 | 7.69% |
| Total | 127 | 100.00% | 13 | 100.00% |
static int
pipe_fasync(int fd, struct file *filp, int on)
{
struct pipe_inode_info *pipe = filp->private_data;
int retval = 0;
__pipe_lock(pipe);
if (filp->f_mode & FMODE_READ)
retval = fasync_helper(fd, filp, on, &pipe->fasync_readers);
if ((filp->f_mode & FMODE_WRITE) && retval >= 0) {
retval = fasync_helper(fd, filp, on, &pipe->fasync_writers);
if (retval < 0 && (filp->f_mode & FMODE_READ))
/* this can happen only if on == T */
fasync_helper(-1, filp, 0, &pipe->fasync_readers);
}
__pipe_unlock(pipe);
return retval;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
dave jones | dave jones | 58 | 44.62% | 1 | 10.00% |
al viro | al viro | 34 | 26.15% | 4 | 40.00% |
oleg nesterov | oleg nesterov | 24 | 18.46% | 1 | 10.00% |
ingo molnar | ingo molnar | 10 | 7.69% | 2 | 20.00% |
pre-git | pre-git | 4 | 3.08% | 2 | 20.00% |
| Total | 130 | 100.00% | 10 | 100.00% |
static void account_pipe_buffers(struct pipe_inode_info *pipe,
unsigned long old, unsigned long new)
{
atomic_long_add(new - old, &pipe->user->pipe_bufs);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
willy tarreau | willy tarreau | 33 | 100.00% | 1 | 100.00% |
| Total | 33 | 100.00% | 1 | 100.00% |
static bool too_many_pipe_buffers_soft(struct user_struct *user)
{
return pipe_user_pages_soft &&
atomic_long_read(&user->pipe_bufs) >= pipe_user_pages_soft;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
willy tarreau | willy tarreau | 24 | 100.00% | 1 | 100.00% |
| Total | 24 | 100.00% | 1 | 100.00% |
static bool too_many_pipe_buffers_hard(struct user_struct *user)
{
return pipe_user_pages_hard &&
atomic_long_read(&user->pipe_bufs) >= pipe_user_pages_hard;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
willy tarreau | willy tarreau | 24 | 100.00% | 1 | 100.00% |
| Total | 24 | 100.00% | 1 | 100.00% |
struct pipe_inode_info *alloc_pipe_info(void)
{
struct pipe_inode_info *pipe;
pipe = kzalloc(sizeof(struct pipe_inode_info), GFP_KERNEL);
if (pipe) {
unsigned long pipe_bufs = PIPE_DEF_BUFFERS;
struct user_struct *user = get_current_user();
if (!too_many_pipe_buffers_hard(user)) {
if (too_many_pipe_buffers_soft(user))
pipe_bufs = 1;
pipe->bufs = kzalloc(sizeof(struct pipe_buffer) * pipe_bufs, GFP_KERNEL);
}
if (pipe->bufs) {
init_waitqueue_head(&pipe->wait);
pipe->r_counter = pipe->w_counter = 1;
pipe->buffers = pipe_bufs;
pipe->user = user;
account_pipe_buffers(pipe, 0, pipe_bufs);
mutex_init(&pipe->mutex);
return pipe;
}
free_uid(user);
kfree(pipe);
}
return NULL;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
willy tarreau | willy tarreau | 57 | 36.54% | 1 | 14.29% |
ingo molnar | ingo molnar | 50 | 32.05% | 2 | 28.57% |
jens axboe | jens axboe | 36 | 23.08% | 1 | 14.29% |
al viro | al viro | 13 | 8.33% | 3 | 42.86% |
| Total | 156 | 100.00% | 7 | 100.00% |
void free_pipe_info(struct pipe_inode_info *pipe)
{
int i;
account_pipe_buffers(pipe, pipe->buffers, 0);
free_uid(pipe->user);
for (i = 0; i < pipe->buffers; i++) {
struct pipe_buffer *buf = pipe->bufs + i;
if (buf->ops)
buf->ops->release(pipe, buf);
}
if (pipe->tmp_page)
__free_page(pipe->tmp_page);
kfree(pipe->bufs);
kfree(pipe);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
linus torvalds | linus torvalds | 65 | 64.36% | 5 | 50.00% |
willy tarreau | willy tarreau | 18 | 17.82% | 1 | 10.00% |
jens axboe | jens axboe | 11 | 10.89% | 2 | 20.00% |
ingo molnar | ingo molnar | 6 | 5.94% | 1 | 10.00% |
al viro | al viro | 1 | 0.99% | 1 | 10.00% |
| Total | 101 | 100.00% | 10 | 100.00% |
static struct vfsmount *pipe_mnt __read_mostly;
/*
* pipefs_dname() is called from d_path().
*/
static char *pipefs_dname(struct dentry *dentry, char *buffer, int buflen)
{
return dynamic_dname(dentry, buffer, buflen, "pipe:[%lu]",
d_inode(dentry)->i_ino);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
eric dumazet | eric dumazet | 35 | 92.11% | 1 | 50.00% |
david howells | david howells | 3 | 7.89% | 1 | 50.00% |
| Total | 38 | 100.00% | 2 | 100.00% |
static const struct dentry_operations pipefs_dentry_operations = {
.d_dname = pipefs_dname,
};
static struct inode * get_pipe_inode(void)
{
struct inode *inode = new_inode_pseudo(pipe_mnt->mnt_sb);
struct pipe_inode_info *pipe;
if (!inode)
goto fail_inode;
inode->i_ino = get_next_ino();
pipe = alloc_pipe_info();
if (!pipe)
goto fail_iput;
inode->i_pipe = pipe;
pipe->files = 2;
pipe->readers = pipe->writers = 1;
inode->i_fop = &pipefifo_fops;
/*
* Mark the inode dirty from the very beginning,
* that way it will never be moved to the dirty
* list because "mark_inode_dirty()" will think
* that it already _is_ on the dirty list.
*/
inode->i_state = I_DIRTY;
inode->i_mode = S_IFIFO | S_IRUSR | S_IWUSR;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;