#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 <asm/uaccess.h>
#include <asm/ioctls.h>
*/
/* Drop the inode semaphore and wait for a pipe event, atomically */
-void pipe_wait(struct inode * inode)
+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(*inode), &wait, TASK_INTERRUPTIBLE|TASK_NONINTERACTIVE);
- mutex_unlock(PIPE_MUTEX(*inode));
+ prepare_to_wait(&pipe->wait, &wait, TASK_INTERRUPTIBLE);
+ if (pipe->inode)
+ mutex_unlock(&pipe->inode->i_mutex);
schedule();
- finish_wait(PIPE_WAIT(*inode), &wait);
- mutex_lock(PIPE_MUTEX(*inode));
+ finish_wait(&pipe->wait, &wait);
+ if (pipe->inode)
+ mutex_lock(&pipe->inode->i_mutex);
}
-static inline int
-pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len)
+static int
+pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len,
+ int atomic)
{
unsigned long copy;
iov++;
copy = min_t(unsigned long, len, iov->iov_len);
- if (copy_from_user(to, iov->iov_base, copy))
- return -EFAULT;
+ if (atomic) {
+ if (__copy_from_user_inatomic(to, iov->iov_base, copy))
+ return -EFAULT;
+ } else {
+ if (copy_from_user(to, iov->iov_base, copy))
+ return -EFAULT;
+ }
to += copy;
len -= copy;
iov->iov_base += copy;
return 0;
}
-static inline int
-pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len)
+static int
+pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len,
+ int atomic)
{
unsigned long copy;
iov++;
copy = min_t(unsigned long, len, iov->iov_len);
- if (copy_to_user(iov->iov_base, from, copy))
- return -EFAULT;
+ if (atomic) {
+ if (__copy_to_user_inatomic(iov->iov_base, from, copy))
+ return -EFAULT;
+ } else {
+ if (copy_to_user(iov->iov_base, from, copy))
+ return -EFAULT;
+ }
from += copy;
len -= copy;
iov->iov_base += copy;
return 0;
}
-static void anon_pipe_buf_release(struct pipe_inode_info *info, struct pipe_buffer *buf)
+/*
+ * Attempt to pre-fault in the user memory, so we can use atomic copies.
+ * Returns the number of bytes not faulted in.
+ */
+static int iov_fault_in_pages_write(struct iovec *iov, unsigned long len)
{
- struct page *page = buf->page;
+ while (!iov->iov_len)
+ iov++;
- if (info->tmp_page) {
- __free_page(page);
- return;
+ while (len > 0) {
+ unsigned long this_len;
+
+ this_len = min_t(unsigned long, len, iov->iov_len);
+ if (fault_in_pages_writeable(iov->iov_base, this_len))
+ break;
+
+ len -= this_len;
+ iov++;
}
- info->tmp_page = page;
+
+ return len;
}
-static void *anon_pipe_buf_map(struct file *file, struct pipe_inode_info *info, struct pipe_buffer *buf)
+/*
+ * Pre-fault in the user memory, so we can use atomic copies.
+ */
+static void iov_fault_in_pages_read(struct iovec *iov, unsigned long len)
+{
+ while (!iov->iov_len)
+ iov++;
+
+ while (len > 0) {
+ unsigned long this_len;
+
+ this_len = min_t(unsigned long, len, iov->iov_len);
+ fault_in_pages_readable(iov->iov_base, this_len);
+ len -= this_len;
+ iov++;
+ }
+}
+
+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
+ page_cache_release(page);
+}
+
+/**
+ * generic_pipe_buf_map - virtually map a pipe buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer that should be mapped
+ * @atomic: whether to use an atomic map
+ *
+ * Description:
+ * This function returns a kernel virtual address mapping for the
+ * pipe_buffer passed in @buf. If @atomic is set, an atomic map is provided
+ * and the caller has to be careful not to fault before calling
+ * the unmap function.
+ *
+ * Note that this function occupies KM_USER0 if @atomic != 0.
+ */
+void *generic_pipe_buf_map(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf, int atomic)
+{
+ if (atomic) {
+ buf->flags |= PIPE_BUF_FLAG_ATOMIC;
+ return kmap_atomic(buf->page, KM_USER0);
+ }
+
return kmap(buf->page);
}
-static void anon_pipe_buf_unmap(struct pipe_inode_info *info, struct pipe_buffer *buf)
+/**
+ * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer that should be unmapped
+ * @map_data: the data that the mapping function returned
+ *
+ * Description:
+ * This function undoes the mapping that ->map() provided.
+ */
+void generic_pipe_buf_unmap(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf, void *map_data)
+{
+ if (buf->flags & PIPE_BUF_FLAG_ATOMIC) {
+ buf->flags &= ~PIPE_BUF_FLAG_ATOMIC;
+ kunmap_atomic(map_data, KM_USER0);
+ } else
+ kunmap(buf->page);
+}
+
+/**
+ * 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)
{
- kunmap(buf->page);
+ 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;
}
-static struct pipe_buf_operations anon_pipe_buf_ops = {
+/**
+ * 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)
+{
+ page_cache_get(buf->page);
+}
+
+/**
+ * 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;
+}
+
+static const struct pipe_buf_operations anon_pipe_buf_ops = {
.can_merge = 1,
- .map = anon_pipe_buf_map,
- .unmap = anon_pipe_buf_unmap,
+ .map = generic_pipe_buf_map,
+ .unmap = generic_pipe_buf_unmap,
+ .confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
+ .steal = generic_pipe_buf_steal,
+ .get = generic_pipe_buf_get,
};
static ssize_t
-pipe_readv(struct file *filp, const struct iovec *_iov,
- unsigned long nr_segs, loff_t *ppos)
+pipe_read(struct kiocb *iocb, const struct iovec *_iov,
+ unsigned long nr_segs, loff_t pos)
{
- struct inode *inode = filp->f_dentry->d_inode;
- struct pipe_inode_info *info;
+ struct file *filp = iocb->ki_filp;
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct pipe_inode_info *pipe;
int do_wakeup;
ssize_t ret;
struct iovec *iov = (struct iovec *)_iov;
do_wakeup = 0;
ret = 0;
- mutex_lock(PIPE_MUTEX(*inode));
- info = inode->i_pipe;
+ mutex_lock(&inode->i_mutex);
+ pipe = inode->i_pipe;
for (;;) {
- int bufs = info->nrbufs;
+ int bufs = pipe->nrbufs;
if (bufs) {
- int curbuf = info->curbuf;
- struct pipe_buffer *buf = info->bufs + curbuf;
- struct pipe_buf_operations *ops = buf->ops;
+ int curbuf = pipe->curbuf;
+ struct pipe_buffer *buf = pipe->bufs + curbuf;
+ const struct pipe_buf_operations *ops = buf->ops;
void *addr;
size_t chars = buf->len;
- int error;
+ int error, atomic;
if (chars > total_len)
chars = total_len;
- addr = ops->map(filp, info, buf);
- error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars);
- ops->unmap(info, buf);
+ error = ops->confirm(pipe, buf);
+ if (error) {
+ if (!ret)
+ error = ret;
+ break;
+ }
+
+ atomic = !iov_fault_in_pages_write(iov, chars);
+redo:
+ addr = ops->map(pipe, buf, atomic);
+ error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic);
+ ops->unmap(pipe, buf, addr);
if (unlikely(error)) {
- if (!ret) ret = -EFAULT;
+ /*
+ * Just retry with the slow path if we failed.
+ */
+ if (atomic) {
+ atomic = 0;
+ goto redo;
+ }
+ if (!ret)
+ ret = error;
break;
}
ret += chars;
buf->len -= chars;
if (!buf->len) {
buf->ops = NULL;
- ops->release(info, buf);
+ ops->release(pipe, buf);
curbuf = (curbuf + 1) & (PIPE_BUFFERS-1);
- info->curbuf = curbuf;
- info->nrbufs = --bufs;
+ pipe->curbuf = curbuf;
+ pipe->nrbufs = --bufs;
do_wakeup = 1;
}
total_len -= chars;
}
if (bufs) /* More to do? */
continue;
- if (!PIPE_WRITERS(*inode))
+ if (!pipe->writers)
break;
- if (!PIPE_WAITING_WRITERS(*inode)) {
+ 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
}
}
if (signal_pending(current)) {
- if (!ret) ret = -ERESTARTSYS;
+ if (!ret)
+ ret = -ERESTARTSYS;
break;
}
if (do_wakeup) {
- wake_up_interruptible_sync(PIPE_WAIT(*inode));
- kill_fasync(PIPE_FASYNC_WRITERS(*inode), SIGIO, POLL_OUT);
+ wake_up_interruptible_sync(&pipe->wait);
+ kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}
- pipe_wait(inode);
+ pipe_wait(pipe);
}
- mutex_unlock(PIPE_MUTEX(*inode));
- /* Signal writers asynchronously that there is more room. */
+ mutex_unlock(&inode->i_mutex);
+
+ /* Signal writers asynchronously that there is more room. */
if (do_wakeup) {
- wake_up_interruptible(PIPE_WAIT(*inode));
- kill_fasync(PIPE_FASYNC_WRITERS(*inode), SIGIO, POLL_OUT);
+ wake_up_interruptible_sync(&pipe->wait);
+ kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}
if (ret > 0)
file_accessed(filp);
}
static ssize_t
-pipe_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos)
-{
- struct iovec iov = { .iov_base = buf, .iov_len = count };
- return pipe_readv(filp, &iov, 1, ppos);
-}
-
-static ssize_t
-pipe_writev(struct file *filp, const struct iovec *_iov,
- unsigned long nr_segs, loff_t *ppos)
+pipe_write(struct kiocb *iocb, const struct iovec *_iov,
+ unsigned long nr_segs, loff_t ppos)
{
- struct inode *inode = filp->f_dentry->d_inode;
- struct pipe_inode_info *info;
+ struct file *filp = iocb->ki_filp;
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct pipe_inode_info *pipe;
ssize_t ret;
int do_wakeup;
struct iovec *iov = (struct iovec *)_iov;
do_wakeup = 0;
ret = 0;
- mutex_lock(PIPE_MUTEX(*inode));
- info = inode->i_pipe;
+ mutex_lock(&inode->i_mutex);
+ pipe = inode->i_pipe;
- if (!PIPE_READERS(*inode)) {
+ 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 (info->nrbufs && chars != 0) {
- int lastbuf = (info->curbuf + info->nrbufs - 1) & (PIPE_BUFFERS-1);
- struct pipe_buffer *buf = info->bufs + lastbuf;
- struct pipe_buf_operations *ops = buf->ops;
+ 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) {
- void *addr = ops->map(filp, info, buf);
- int error = pipe_iov_copy_from_user(offset + addr, iov, chars);
- ops->unmap(info, buf);
+ int error, atomic = 1;
+ void *addr;
+
+ error = ops->confirm(pipe, buf);
+ if (error)
+ goto out;
+
+ iov_fault_in_pages_read(iov, chars);
+redo1:
+ addr = ops->map(pipe, buf, atomic);
+ error = pipe_iov_copy_from_user(offset + addr, iov,
+ chars, atomic);
+ ops->unmap(pipe, buf, addr);
ret = error;
do_wakeup = 1;
- if (error)
+ if (error) {
+ if (atomic) {
+ atomic = 0;
+ goto redo1;
+ }
goto out;
+ }
buf->len += chars;
total_len -= chars;
ret = chars;
for (;;) {
int bufs;
- if (!PIPE_READERS(*inode)) {
+
+ if (!pipe->readers) {
send_sig(SIGPIPE, current, 0);
- if (!ret) ret = -EPIPE;
+ if (!ret)
+ ret = -EPIPE;
break;
}
- bufs = info->nrbufs;
+ bufs = pipe->nrbufs;
if (bufs < PIPE_BUFFERS) {
- int newbuf = (info->curbuf + bufs) & (PIPE_BUFFERS-1);
- struct pipe_buffer *buf = info->bufs + newbuf;
- struct page *page = info->tmp_page;
- int error;
+ int newbuf = (pipe->curbuf + bufs) & (PIPE_BUFFERS-1);
+ struct pipe_buffer *buf = pipe->bufs + newbuf;
+ struct page *page = pipe->tmp_page;
+ char *src;
+ int error, atomic = 1;
if (!page) {
page = alloc_page(GFP_HIGHUSER);
ret = ret ? : -ENOMEM;
break;
}
- info->tmp_page = page;
+ pipe->tmp_page = page;
}
- /* Always wakeup, even if the copy fails. Otherwise
+ /* 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?
if (chars > total_len)
chars = total_len;
- error = pipe_iov_copy_from_user(kmap(page), iov, chars);
- kunmap(page);
+ iov_fault_in_pages_read(iov, chars);
+redo2:
+ if (atomic)
+ src = kmap_atomic(page, KM_USER0);
+ else
+ src = kmap(page);
+
+ error = pipe_iov_copy_from_user(src, iov, chars,
+ atomic);
+ if (atomic)
+ kunmap_atomic(src, KM_USER0);
+ else
+ kunmap(page);
+
if (unlikely(error)) {
- if (!ret) ret = -EFAULT;
+ if (atomic) {
+ atomic = 0;
+ goto redo2;
+ }
+ if (!ret)
+ ret = error;
break;
}
ret += chars;
buf->ops = &anon_pipe_buf_ops;
buf->offset = 0;
buf->len = chars;
- info->nrbufs = ++bufs;
- info->tmp_page = NULL;
+ pipe->nrbufs = ++bufs;
+ pipe->tmp_page = NULL;
total_len -= chars;
if (!total_len)
if (bufs < PIPE_BUFFERS)
continue;
if (filp->f_flags & O_NONBLOCK) {
- if (!ret) ret = -EAGAIN;
+ if (!ret)
+ ret = -EAGAIN;
break;
}
if (signal_pending(current)) {
- if (!ret) ret = -ERESTARTSYS;
+ if (!ret)
+ ret = -ERESTARTSYS;
break;
}
if (do_wakeup) {
- wake_up_interruptible_sync(PIPE_WAIT(*inode));
- kill_fasync(PIPE_FASYNC_READERS(*inode), SIGIO, POLL_IN);
+ wake_up_interruptible_sync(&pipe->wait);
+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
do_wakeup = 0;
}
- PIPE_WAITING_WRITERS(*inode)++;
- pipe_wait(inode);
- PIPE_WAITING_WRITERS(*inode)--;
+ pipe->waiting_writers++;
+ pipe_wait(pipe);
+ pipe->waiting_writers--;
}
out:
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_unlock(&inode->i_mutex);
if (do_wakeup) {
- wake_up_interruptible(PIPE_WAIT(*inode));
- kill_fasync(PIPE_FASYNC_READERS(*inode), SIGIO, POLL_IN);
+ wake_up_interruptible_sync(&pipe->wait);
+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
}
if (ret > 0)
- inode_update_time(inode, 1); /* mtime and ctime */
+ file_update_time(filp);
return ret;
}
static ssize_t
-pipe_write(struct file *filp, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count };
- return pipe_writev(filp, &iov, 1, ppos);
-}
-
-static ssize_t
bad_pipe_r(struct file *filp, char __user *buf, size_t count, loff_t *ppos)
{
return -EBADF;
}
static ssize_t
-bad_pipe_w(struct file *filp, const char __user *buf, size_t count, loff_t *ppos)
+bad_pipe_w(struct file *filp, const char __user *buf, size_t count,
+ loff_t *ppos)
{
return -EBADF;
}
-static int
-pipe_ioctl(struct inode *pino, struct file *filp,
- unsigned int cmd, unsigned long arg)
+static long pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
- struct inode *inode = filp->f_dentry->d_inode;
- struct pipe_inode_info *info;
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct pipe_inode_info *pipe;
int count, buf, nrbufs;
switch (cmd) {
case FIONREAD:
- mutex_lock(PIPE_MUTEX(*inode));
- info = inode->i_pipe;
+ mutex_lock(&inode->i_mutex);
+ pipe = inode->i_pipe;
count = 0;
- buf = info->curbuf;
- nrbufs = info->nrbufs;
+ buf = pipe->curbuf;
+ nrbufs = pipe->nrbufs;
while (--nrbufs >= 0) {
- count += info->bufs[buf].len;
+ count += pipe->bufs[buf].len;
buf = (buf+1) & (PIPE_BUFFERS-1);
}
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_unlock(&inode->i_mutex);
+
return put_user(count, (int __user *)arg);
default:
return -EINVAL;
pipe_poll(struct file *filp, poll_table *wait)
{
unsigned int mask;
- struct inode *inode = filp->f_dentry->d_inode;
- struct pipe_inode_info *info = inode->i_pipe;
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct pipe_inode_info *pipe = inode->i_pipe;
int nrbufs;
- poll_wait(filp, PIPE_WAIT(*inode), wait);
+ poll_wait(filp, &pipe->wait, wait);
/* Reading only -- no need for acquiring the semaphore. */
- nrbufs = info->nrbufs;
+ nrbufs = pipe->nrbufs;
mask = 0;
if (filp->f_mode & FMODE_READ) {
mask = (nrbufs > 0) ? POLLIN | POLLRDNORM : 0;
- if (!PIPE_WRITERS(*inode) && filp->f_version != PIPE_WCOUNTER(*inode))
+ if (!pipe->writers && filp->f_version != pipe->w_counter)
mask |= POLLHUP;
}
* Most Unices do not set POLLERR for FIFOs but on Linux they
* behave exactly like pipes for poll().
*/
- if (!PIPE_READERS(*inode))
+ if (!pipe->readers)
mask |= POLLERR;
}
static int
pipe_release(struct inode *inode, int decr, int decw)
{
- mutex_lock(PIPE_MUTEX(*inode));
- PIPE_READERS(*inode) -= decr;
- PIPE_WRITERS(*inode) -= decw;
- if (!PIPE_READERS(*inode) && !PIPE_WRITERS(*inode)) {
+ struct pipe_inode_info *pipe;
+
+ mutex_lock(&inode->i_mutex);
+ pipe = inode->i_pipe;
+ pipe->readers -= decr;
+ pipe->writers -= decw;
+
+ if (!pipe->readers && !pipe->writers) {
free_pipe_info(inode);
} else {
- wake_up_interruptible(PIPE_WAIT(*inode));
- kill_fasync(PIPE_FASYNC_READERS(*inode), SIGIO, POLL_IN);
- kill_fasync(PIPE_FASYNC_WRITERS(*inode), SIGIO, POLL_OUT);
+ wake_up_interruptible_sync(&pipe->wait);
+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
+ kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
}
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_unlock(&inode->i_mutex);
return 0;
}
static int
pipe_read_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
int retval;
- mutex_lock(PIPE_MUTEX(*inode));
- retval = fasync_helper(fd, filp, on, PIPE_FASYNC_READERS(*inode));
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_lock(&inode->i_mutex);
+ retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_readers);
+ mutex_unlock(&inode->i_mutex);
if (retval < 0)
return retval;
static int
pipe_write_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
int retval;
- mutex_lock(PIPE_MUTEX(*inode));
- retval = fasync_helper(fd, filp, on, PIPE_FASYNC_WRITERS(*inode));
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_lock(&inode->i_mutex);
+ retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_writers);
+ mutex_unlock(&inode->i_mutex);
if (retval < 0)
return retval;
static int
pipe_rdwr_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct pipe_inode_info *pipe = inode->i_pipe;
int retval;
- mutex_lock(PIPE_MUTEX(*inode));
-
- retval = fasync_helper(fd, filp, on, PIPE_FASYNC_READERS(*inode));
-
- if (retval >= 0)
- retval = fasync_helper(fd, filp, on, PIPE_FASYNC_WRITERS(*inode));
-
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_lock(&inode->i_mutex);
+ retval = fasync_helper(fd, filp, on, &pipe->fasync_readers);
+ if (retval >= 0) {
+ retval = fasync_helper(fd, filp, on, &pipe->fasync_writers);
+ if (retval < 0) /* this can happen only if on == T */
+ fasync_helper(-1, filp, 0, &pipe->fasync_readers);
+ }
+ mutex_unlock(&inode->i_mutex);
if (retval < 0)
return retval;
static int
pipe_read_release(struct inode *inode, struct file *filp)
{
- pipe_read_fasync(-1, filp, 0);
return pipe_release(inode, 1, 0);
}
static int
pipe_write_release(struct inode *inode, struct file *filp)
{
- pipe_write_fasync(-1, filp, 0);
return pipe_release(inode, 0, 1);
}
{
int decr, decw;
- pipe_rdwr_fasync(-1, filp, 0);
decr = (filp->f_mode & FMODE_READ) != 0;
decw = (filp->f_mode & FMODE_WRITE) != 0;
return pipe_release(inode, decr, decw);
{
/* We could have perhaps used atomic_t, but this and friends
below are the only places. So it doesn't seem worthwhile. */
- mutex_lock(PIPE_MUTEX(*inode));
- PIPE_READERS(*inode)++;
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_lock(&inode->i_mutex);
+ inode->i_pipe->readers++;
+ mutex_unlock(&inode->i_mutex);
return 0;
}
static int
pipe_write_open(struct inode *inode, struct file *filp)
{
- mutex_lock(PIPE_MUTEX(*inode));
- PIPE_WRITERS(*inode)++;
- mutex_unlock(PIPE_MUTEX(*inode));
+ mutex_lock(&inode->i_mutex);
+ inode->i_pipe->writers++;
+ mutex_unlock(&inode->i_mutex);
return 0;
}
static int
pipe_rdwr_open(struct inode *inode, struct file *filp)
{
- mutex_lock(PIPE_MUTEX(*inode));
+ mutex_lock(&inode->i_mutex);
if (filp->f_mode & FMODE_READ)
- PIPE_READERS(*inode)++;
+ inode->i_pipe->readers++;
if (filp->f_mode & FMODE_WRITE)
- PIPE_WRITERS(*inode)++;
- mutex_unlock(PIPE_MUTEX(*inode));
+ inode->i_pipe->writers++;
+ mutex_unlock(&inode->i_mutex);
return 0;
}
/*
* The file_operations structs are not static because they
* are also used in linux/fs/fifo.c to do operations on FIFOs.
+ *
+ * Pipes reuse fifos' file_operations structs.
*/
-struct file_operations read_fifo_fops = {
+const struct file_operations read_pipefifo_fops = {
.llseek = no_llseek,
- .read = pipe_read,
- .readv = pipe_readv,
+ .read = do_sync_read,
+ .aio_read = pipe_read,
.write = bad_pipe_w,
.poll = pipe_poll,
- .ioctl = pipe_ioctl,
+ .unlocked_ioctl = pipe_ioctl,
.open = pipe_read_open,
.release = pipe_read_release,
.fasync = pipe_read_fasync,
};
-struct file_operations write_fifo_fops = {
+const struct file_operations write_pipefifo_fops = {
.llseek = no_llseek,
.read = bad_pipe_r,
- .write = pipe_write,
- .writev = pipe_writev,
+ .write = do_sync_write,
+ .aio_write = pipe_write,
.poll = pipe_poll,
- .ioctl = pipe_ioctl,
+ .unlocked_ioctl = pipe_ioctl,
.open = pipe_write_open,
.release = pipe_write_release,
.fasync = pipe_write_fasync,
};
-struct file_operations rdwr_fifo_fops = {
+const struct file_operations rdwr_pipefifo_fops = {
.llseek = no_llseek,
- .read = pipe_read,
- .readv = pipe_readv,
- .write = pipe_write,
- .writev = pipe_writev,
+ .read = do_sync_read,
+ .aio_read = pipe_read,
+ .write = do_sync_write,
+ .aio_write = pipe_write,
.poll = pipe_poll,
- .ioctl = pipe_ioctl,
+ .unlocked_ioctl = pipe_ioctl,
.open = pipe_rdwr_open,
.release = pipe_rdwr_release,
.fasync = pipe_rdwr_fasync,
};
-struct file_operations read_pipe_fops = {
- .llseek = no_llseek,
- .read = pipe_read,
- .readv = pipe_readv,
- .write = bad_pipe_w,
- .poll = pipe_poll,
- .ioctl = pipe_ioctl,
- .open = pipe_read_open,
- .release = pipe_read_release,
- .fasync = pipe_read_fasync,
-};
+struct pipe_inode_info * alloc_pipe_info(struct inode *inode)
+{
+ struct pipe_inode_info *pipe;
-struct file_operations write_pipe_fops = {
- .llseek = no_llseek,
- .read = bad_pipe_r,
- .write = pipe_write,
- .writev = pipe_writev,
- .poll = pipe_poll,
- .ioctl = pipe_ioctl,
- .open = pipe_write_open,
- .release = pipe_write_release,
- .fasync = pipe_write_fasync,
-};
+ pipe = kzalloc(sizeof(struct pipe_inode_info), GFP_KERNEL);
+ if (pipe) {
+ init_waitqueue_head(&pipe->wait);
+ pipe->r_counter = pipe->w_counter = 1;
+ pipe->inode = inode;
+ }
-struct file_operations rdwr_pipe_fops = {
- .llseek = no_llseek,
- .read = pipe_read,
- .readv = pipe_readv,
- .write = pipe_write,
- .writev = pipe_writev,
- .poll = pipe_poll,
- .ioctl = pipe_ioctl,
- .open = pipe_rdwr_open,
- .release = pipe_rdwr_release,
- .fasync = pipe_rdwr_fasync,
-};
+ return pipe;
+}
-void free_pipe_info(struct inode *inode)
+void __free_pipe_info(struct pipe_inode_info *pipe)
{
int i;
- struct pipe_inode_info *info = inode->i_pipe;
- inode->i_pipe = NULL;
for (i = 0; i < PIPE_BUFFERS; i++) {
- struct pipe_buffer *buf = info->bufs + i;
+ struct pipe_buffer *buf = pipe->bufs + i;
if (buf->ops)
- buf->ops->release(info, buf);
+ buf->ops->release(pipe, buf);
}
- if (info->tmp_page)
- __free_page(info->tmp_page);
- kfree(info);
+ if (pipe->tmp_page)
+ __free_page(pipe->tmp_page);
+ kfree(pipe);
}
-struct inode* pipe_new(struct inode* inode)
+void free_pipe_info(struct inode *inode)
{
- struct pipe_inode_info *info;
-
- info = kmalloc(sizeof(struct pipe_inode_info), GFP_KERNEL);
- if (!info)
- goto fail_page;
- memset(info, 0, sizeof(*info));
- inode->i_pipe = info;
-
- init_waitqueue_head(PIPE_WAIT(*inode));
- PIPE_RCOUNTER(*inode) = PIPE_WCOUNTER(*inode) = 1;
-
- return inode;
-fail_page:
- return NULL;
+ __free_pipe_info(inode->i_pipe);
+ inode->i_pipe = NULL;
}
-static struct vfsmount *pipe_mnt;
+static struct vfsmount *pipe_mnt __read_mostly;
static int pipefs_delete_dentry(struct dentry *dentry)
{
- return 1;
+ /*
+ * At creation time, we pretended this dentry was hashed
+ * (by clearing DCACHE_UNHASHED bit in d_flags)
+ * At delete time, we restore the truth : not hashed.
+ * (so that dput() can proceed correctly)
+ */
+ dentry->d_flags |= DCACHE_UNHASHED;
+ return 0;
+}
+
+/*
+ * 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]",
+ dentry->d_inode->i_ino);
}
+
static struct dentry_operations pipefs_dentry_operations = {
.d_delete = pipefs_delete_dentry,
+ .d_dname = pipefs_dname,
};
static struct inode * get_pipe_inode(void)
{
struct inode *inode = new_inode(pipe_mnt->mnt_sb);
+ struct pipe_inode_info *pipe;
if (!inode)
goto fail_inode;
- if(!pipe_new(inode))
+ pipe = alloc_pipe_info(inode);
+ if (!pipe)
goto fail_iput;
- PIPE_READERS(*inode) = PIPE_WRITERS(*inode) = 1;
- inode->i_fop = &rdwr_pipe_fops;
+ inode->i_pipe = pipe;
+
+ pipe->readers = pipe->writers = 1;
+ inode->i_fop = &rdwr_pipefifo_fops;
/*
* Mark the inode dirty from the very beginning,
*/
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_uid = current_fsuid();
+ inode->i_gid = current_fsgid();
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- inode->i_blksize = PAGE_SIZE;
+
return inode;
fail_iput:
iput(inode);
+
fail_inode:
return NULL;
}
-int do_pipe(int *fd)
+struct file *create_write_pipe(int flags)
{
- struct qstr this;
- char name[32];
+ int err;
+ struct inode *inode;
+ struct file *f;
struct dentry *dentry;
- struct inode * inode;
- struct file *f1, *f2;
- int error;
- int i,j;
-
- error = -ENFILE;
- f1 = get_empty_filp();
- if (!f1)
- goto no_files;
-
- f2 = get_empty_filp();
- if (!f2)
- goto close_f1;
+ struct qstr name = { .name = "" };
+ err = -ENFILE;
inode = get_pipe_inode();
if (!inode)
- goto close_f12;
-
- error = get_unused_fd();
- if (error < 0)
- goto close_f12_inode;
- i = error;
+ goto err;
- error = get_unused_fd();
- if (error < 0)
- goto close_f12_inode_i;
- j = error;
-
- error = -ENOMEM;
- sprintf(name, "[%lu]", inode->i_ino);
- this.name = name;
- this.len = strlen(name);
- this.hash = inode->i_ino; /* will go */
- dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &this);
+ err = -ENOMEM;
+ dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name);
if (!dentry)
- goto close_f12_inode_i_j;
+ goto err_inode;
+
dentry->d_op = &pipefs_dentry_operations;
- d_add(dentry, inode);
- f1->f_vfsmnt = f2->f_vfsmnt = mntget(mntget(pipe_mnt));
- f1->f_dentry = f2->f_dentry = dget(dentry);
- f1->f_mapping = f2->f_mapping = inode->i_mapping;
-
- /* read file */
- f1->f_pos = f2->f_pos = 0;
- f1->f_flags = O_RDONLY;
- f1->f_op = &read_pipe_fops;
- f1->f_mode = FMODE_READ;
- f1->f_version = 0;
-
- /* write file */
- f2->f_flags = O_WRONLY;
- f2->f_op = &write_pipe_fops;
- f2->f_mode = FMODE_WRITE;
- f2->f_version = 0;
-
- fd_install(i, f1);
- fd_install(j, f2);
- fd[0] = i;
- fd[1] = j;
- return 0;
+ /*
+ * We dont want to publish this dentry into global dentry hash table.
+ * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
+ * This permits a working /proc/$pid/fd/XXX on pipes
+ */
+ dentry->d_flags &= ~DCACHE_UNHASHED;
+ d_instantiate(dentry, inode);
+
+ err = -ENFILE;
+ f = alloc_file(pipe_mnt, dentry, FMODE_WRITE, &write_pipefifo_fops);
+ if (!f)
+ goto err_dentry;
+ f->f_mapping = inode->i_mapping;
-close_f12_inode_i_j:
- put_unused_fd(j);
-close_f12_inode_i:
- put_unused_fd(i);
-close_f12_inode:
+ f->f_flags = O_WRONLY | (flags & O_NONBLOCK);
+ f->f_version = 0;
+
+ return f;
+
+ err_dentry:
+ free_pipe_info(inode);
+ dput(dentry);
+ return ERR_PTR(err);
+
+ err_inode:
free_pipe_info(inode);
iput(inode);
-close_f12:
- put_filp(f2);
-close_f1:
- put_filp(f1);
-no_files:
- return error;
+ err:
+ return ERR_PTR(err);
+}
+
+void free_write_pipe(struct file *f)
+{
+ free_pipe_info(f->f_dentry->d_inode);
+ path_put(&f->f_path);
+ put_filp(f);
+}
+
+struct file *create_read_pipe(struct file *wrf, int flags)
+{
+ struct file *f = get_empty_filp();
+ if (!f)
+ return ERR_PTR(-ENFILE);
+
+ /* Grab pipe from the writer */
+ f->f_path = wrf->f_path;
+ path_get(&wrf->f_path);
+ f->f_mapping = wrf->f_path.dentry->d_inode->i_mapping;
+
+ f->f_pos = 0;
+ f->f_flags = O_RDONLY | (flags & O_NONBLOCK);
+ f->f_op = &read_pipefifo_fops;
+ f->f_mode = FMODE_READ;
+ f->f_version = 0;
+
+ return f;
+}
+
+int do_pipe_flags(int *fd, int flags)
+{
+ struct file *fw, *fr;
+ int error;
+ int fdw, fdr;
+
+ if (flags & ~(O_CLOEXEC | O_NONBLOCK))
+ return -EINVAL;
+
+ fw = create_write_pipe(flags);
+ if (IS_ERR(fw))
+ return PTR_ERR(fw);
+ fr = create_read_pipe(fw, flags);
+ error = PTR_ERR(fr);
+ if (IS_ERR(fr))
+ goto err_write_pipe;
+
+ error = get_unused_fd_flags(flags);
+ if (error < 0)
+ goto err_read_pipe;
+ fdr = error;
+
+ error = get_unused_fd_flags(flags);
+ if (error < 0)
+ goto err_fdr;
+ fdw = error;
+
+ audit_fd_pair(fdr, fdw);
+ fd_install(fdr, fr);
+ fd_install(fdw, fw);
+ fd[0] = fdr;
+ fd[1] = fdw;
+
+ return 0;
+
+ err_fdr:
+ put_unused_fd(fdr);
+ err_read_pipe:
+ path_put(&fr->f_path);
+ put_filp(fr);
+ err_write_pipe:
+ free_write_pipe(fw);
+ return error;
+}
+
+int do_pipe(int *fd)
+{
+ return do_pipe_flags(fd, 0);
+}
+
+/*
+ * sys_pipe() is the normal C calling standard for creating
+ * a pipe. It's not the way Unix traditionally does this, though.
+ */
+SYSCALL_DEFINE2(pipe2, int __user *, fildes, int, flags)
+{
+ int fd[2];
+ int error;
+
+ error = do_pipe_flags(fd, flags);
+ if (!error) {
+ if (copy_to_user(fildes, fd, sizeof(fd))) {
+ sys_close(fd[0]);
+ sys_close(fd[1]);
+ error = -EFAULT;
+ }
+ }
+ return error;
+}
+
+SYSCALL_DEFINE1(pipe, int __user *, fildes)
+{
+ return sys_pipe2(fildes, 0);
}
/*
* any operations on the root directory. However, we need a non-trivial
* d_name - pipe: will go nicely and kill the special-casing in procfs.
*/
-
-static struct super_block *pipefs_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int pipefs_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data,
+ struct vfsmount *mnt)
{
- return get_sb_pseudo(fs_type, "pipe:", NULL, PIPEFS_MAGIC);
+ return get_sb_pseudo(fs_type, "pipe:", NULL, PIPEFS_MAGIC, mnt);
}
static struct file_system_type pipe_fs_type = {
static int __init init_pipe_fs(void)
{
int err = register_filesystem(&pipe_fs_type);
+
if (!err) {
pipe_mnt = kern_mount(&pipe_fs_type);
if (IS_ERR(pipe_mnt)) {
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff