#include <linux/audit.h>
#include <linux/syscalls.h>
#include <linux/fcntl.h>
+#include <linux/aio.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
static void pipe_lock_nested(struct pipe_inode_info *pipe, int subclass)
{
- if (pipe->inode)
- mutex_lock_nested(&pipe->inode->i_mutex, subclass);
+ if (pipe->files)
+ mutex_lock_nested(&pipe->mutex, subclass);
}
void pipe_lock(struct pipe_inode_info *pipe)
void pipe_unlock(struct pipe_inode_info *pipe)
{
- if (pipe->inode)
- mutex_unlock(&pipe->inode->i_mutex);
+ if (pipe->files)
+ mutex_unlock(&pipe->mutex);
}
EXPORT_SYMBOL(pipe_unlock);
+static inline void __pipe_lock(struct pipe_inode_info *pipe)
+{
+ mutex_lock_nested(&pipe->mutex, I_MUTEX_PARENT);
+}
+
+static inline void __pipe_unlock(struct pipe_inode_info *pipe)
+{
+ mutex_unlock(&pipe->mutex);
+}
+
void pipe_double_lock(struct pipe_inode_info *pipe1,
struct pipe_inode_info *pipe2)
{
unsigned long nr_segs, loff_t pos)
{
struct file *filp = iocb->ki_filp;
- struct inode *inode = file_inode(filp);
- struct pipe_inode_info *pipe;
+ struct pipe_inode_info *pipe = filp->private_data;
int do_wakeup;
ssize_t ret;
struct iovec *iov = (struct iovec *)_iov;
do_wakeup = 0;
ret = 0;
- mutex_lock(&inode->i_mutex);
- pipe = inode->i_pipe;
+ __pipe_lock(pipe);
for (;;) {
int bufs = pipe->nrbufs;
if (bufs) {
}
pipe_wait(pipe);
}
- mutex_unlock(&inode->i_mutex);
+ __pipe_unlock(pipe);
/* Signal writers asynchronously that there is more room. */
if (do_wakeup) {
unsigned long nr_segs, loff_t ppos)
{
struct file *filp = iocb->ki_filp;
- struct inode *inode = file_inode(filp);
- struct pipe_inode_info *pipe;
+ struct pipe_inode_info *pipe = filp->private_data;
ssize_t ret;
int do_wakeup;
struct iovec *iov = (struct iovec *)_iov;
do_wakeup = 0;
ret = 0;
- mutex_lock(&inode->i_mutex);
- pipe = inode->i_pipe;
+ __pipe_lock(pipe);
if (!pipe->readers) {
send_sig(SIGPIPE, current, 0);
pipe->waiting_writers--;
}
out:
- mutex_unlock(&inode->i_mutex);
+ __pipe_unlock(pipe);
if (do_wakeup) {
wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
return ret;
}
-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)
-{
- return -EBADF;
-}
-
static long pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
- struct inode *inode = file_inode(filp);
- struct pipe_inode_info *pipe;
+ struct pipe_inode_info *pipe = filp->private_data;
int count, buf, nrbufs;
switch (cmd) {
case FIONREAD:
- mutex_lock(&inode->i_mutex);
- pipe = inode->i_pipe;
+ __pipe_lock(pipe);
count = 0;
buf = pipe->curbuf;
nrbufs = pipe->nrbufs;
count += pipe->bufs[buf].len;
buf = (buf+1) & (pipe->buffers - 1);
}
- mutex_unlock(&inode->i_mutex);
+ __pipe_unlock(pipe);
return put_user(count, (int __user *)arg);
default:
pipe_poll(struct file *filp, poll_table *wait)
{
unsigned int mask;
- struct inode *inode = file_inode(filp);
- struct pipe_inode_info *pipe = inode->i_pipe;
+ struct pipe_inode_info *pipe = filp->private_data;
int nrbufs;
poll_wait(filp, &pipe->wait, wait);
}
static int
-pipe_release(struct inode *inode, int decr, int decw)
+pipe_release(struct inode *inode, struct file *file)
{
- struct pipe_inode_info *pipe;
+ struct pipe_inode_info *pipe = inode->i_pipe;
+ int kill = 0;
- mutex_lock(&inode->i_mutex);
- pipe = inode->i_pipe;
- pipe->readers -= decr;
- pipe->writers -= decw;
+ __pipe_lock(pipe);
+ if (file->f_mode & FMODE_READ)
+ pipe->readers--;
+ if (file->f_mode & FMODE_WRITE)
+ pipe->writers--;
- if (!pipe->readers && !pipe->writers) {
- free_pipe_info(inode);
- } else {
+ 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);
}
- mutex_unlock(&inode->i_mutex);
-
- return 0;
-}
-
-static int
-pipe_read_fasync(int fd, struct file *filp, int on)
-{
- struct inode *inode = file_inode(filp);
- int retval;
-
- mutex_lock(&inode->i_mutex);
- retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_readers);
- mutex_unlock(&inode->i_mutex);
-
- return retval;
-}
-
-
-static int
-pipe_write_fasync(int fd, struct file *filp, int on)
-{
- struct inode *inode = file_inode(filp);
- int retval;
+ spin_lock(&inode->i_lock);
+ if (!--pipe->files) {
+ inode->i_pipe = NULL;
+ kill = 1;
+ }
+ spin_unlock(&inode->i_lock);
+ __pipe_unlock(pipe);
- mutex_lock(&inode->i_mutex);
- retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_writers);
- mutex_unlock(&inode->i_mutex);
+ if (kill)
+ free_pipe_info(pipe);
- return retval;
+ return 0;
}
-
static int
-pipe_rdwr_fasync(int fd, struct file *filp, int on)
+pipe_fasync(int fd, struct file *filp, int on)
{
- struct inode *inode = file_inode(filp);
- struct pipe_inode_info *pipe = inode->i_pipe;
- int retval;
+ struct pipe_inode_info *pipe = filp->private_data;
+ int retval = 0;
- mutex_lock(&inode->i_mutex);
- retval = fasync_helper(fd, filp, on, &pipe->fasync_readers);
- if (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) /* this can happen only if on == T */
+ if (retval < 0 && (filp->f_mode & FMODE_READ))
+ /* this can happen only if on == T */
fasync_helper(-1, filp, 0, &pipe->fasync_readers);
}
- mutex_unlock(&inode->i_mutex);
+ __pipe_unlock(pipe);
return retval;
}
-
-static int
-pipe_read_release(struct inode *inode, struct file *filp)
-{
- return pipe_release(inode, 1, 0);
-}
-
-static int
-pipe_write_release(struct inode *inode, struct file *filp)
-{
- return pipe_release(inode, 0, 1);
-}
-
-static int
-pipe_rdwr_release(struct inode *inode, struct file *filp)
-{
- int decr, decw;
-
- decr = (filp->f_mode & FMODE_READ) != 0;
- decw = (filp->f_mode & FMODE_WRITE) != 0;
- return pipe_release(inode, decr, decw);
-}
-
-static int
-pipe_read_open(struct inode *inode, struct file *filp)
-{
- int ret = -ENOENT;
-
- mutex_lock(&inode->i_mutex);
-
- if (inode->i_pipe) {
- ret = 0;
- inode->i_pipe->readers++;
- }
-
- mutex_unlock(&inode->i_mutex);
-
- return ret;
-}
-
-static int
-pipe_write_open(struct inode *inode, struct file *filp)
-{
- int ret = -ENOENT;
-
- mutex_lock(&inode->i_mutex);
-
- if (inode->i_pipe) {
- ret = 0;
- inode->i_pipe->writers++;
- }
-
- mutex_unlock(&inode->i_mutex);
-
- return ret;
-}
-
-static int
-pipe_rdwr_open(struct inode *inode, struct file *filp)
-{
- int ret = -ENOENT;
-
- if (!(filp->f_mode & (FMODE_READ|FMODE_WRITE)))
- return -EINVAL;
-
- mutex_lock(&inode->i_mutex);
-
- if (inode->i_pipe) {
- ret = 0;
- if (filp->f_mode & FMODE_READ)
- inode->i_pipe->readers++;
- if (filp->f_mode & FMODE_WRITE)
- inode->i_pipe->writers++;
- }
-
- mutex_unlock(&inode->i_mutex);
-
- return ret;
-}
-
-/*
- * 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.
- */
-const struct file_operations read_pipefifo_fops = {
- .llseek = no_llseek,
- .read = do_sync_read,
- .aio_read = pipe_read,
- .write = bad_pipe_w,
- .poll = pipe_poll,
- .unlocked_ioctl = pipe_ioctl,
- .open = pipe_read_open,
- .release = pipe_read_release,
- .fasync = pipe_read_fasync,
-};
-
-const struct file_operations write_pipefifo_fops = {
- .llseek = no_llseek,
- .read = bad_pipe_r,
- .write = do_sync_write,
- .aio_write = pipe_write,
- .poll = pipe_poll,
- .unlocked_ioctl = pipe_ioctl,
- .open = pipe_write_open,
- .release = pipe_write_release,
- .fasync = pipe_write_fasync,
-};
-
-const struct file_operations rdwr_pipefifo_fops = {
- .llseek = no_llseek,
- .read = do_sync_read,
- .aio_read = pipe_read,
- .write = do_sync_write,
- .aio_write = pipe_write,
- .poll = pipe_poll,
- .unlocked_ioctl = pipe_ioctl,
- .open = pipe_rdwr_open,
- .release = pipe_rdwr_release,
- .fasync = pipe_rdwr_fasync,
-};
-
-struct pipe_inode_info * alloc_pipe_info(struct inode *inode)
+struct pipe_inode_info *alloc_pipe_info(void)
{
struct pipe_inode_info *pipe;
if (pipe->bufs) {
init_waitqueue_head(&pipe->wait);
pipe->r_counter = pipe->w_counter = 1;
- pipe->inode = inode;
pipe->buffers = PIPE_DEF_BUFFERS;
+ mutex_init(&pipe->mutex);
return pipe;
}
kfree(pipe);
return NULL;
}
-void __free_pipe_info(struct pipe_inode_info *pipe)
+void free_pipe_info(struct pipe_inode_info *pipe)
{
int i;
kfree(pipe);
}
-void free_pipe_info(struct inode *inode)
-{
- __free_pipe_info(inode->i_pipe);
- inode->i_pipe = NULL;
-}
-
static struct vfsmount *pipe_mnt __read_mostly;
/*
inode->i_ino = get_next_ino();
- pipe = alloc_pipe_info(inode);
+ pipe = alloc_pipe_info();
if (!pipe)
goto fail_iput;
- inode->i_pipe = pipe;
+ inode->i_pipe = pipe;
+ pipe->files = 2;
pipe->readers = pipe->writers = 1;
- inode->i_fop = &rdwr_pipefifo_fops;
+ inode->i_fop = &pipefifo_fops;
/*
* Mark the inode dirty from the very beginning,
d_instantiate(path.dentry, inode);
err = -ENFILE;
- f = alloc_file(&path, FMODE_WRITE, &write_pipefifo_fops);
+ f = alloc_file(&path, FMODE_WRITE, &pipefifo_fops);
if (IS_ERR(f))
goto err_dentry;
f->f_flags = O_WRONLY | (flags & (O_NONBLOCK | O_DIRECT));
+ f->private_data = inode->i_pipe;
- res[0] = alloc_file(&path, FMODE_READ, &read_pipefifo_fops);
+ res[0] = alloc_file(&path, FMODE_READ, &pipefifo_fops);
if (IS_ERR(res[0]))
goto err_file;
path_get(&path);
+ res[0]->private_data = inode->i_pipe;
res[0]->f_flags = O_RDONLY | (flags & O_NONBLOCK);
res[1] = f;
return 0;
err_file:
put_filp(f);
err_dentry:
- free_pipe_info(inode);
+ free_pipe_info(inode->i_pipe);
path_put(&path);
return err;
err_inode:
- free_pipe_info(inode);
+ free_pipe_info(inode->i_pipe);
iput(inode);
return err;
}
return sys_pipe2(fildes, 0);
}
+static int wait_for_partner(struct pipe_inode_info *pipe, unsigned int *cnt)
+{
+ int cur = *cnt;
+
+ while (cur == *cnt) {
+ pipe_wait(pipe);
+ if (signal_pending(current))
+ break;
+ }
+ return cur == *cnt ? -ERESTARTSYS : 0;
+}
+
+static void wake_up_partner(struct pipe_inode_info *pipe)
+{
+ wake_up_interruptible(&pipe->wait);
+}
+
+static int fifo_open(struct inode *inode, struct file *filp)
+{
+ struct pipe_inode_info *pipe;
+ bool is_pipe = inode->i_sb->s_magic == PIPEFS_MAGIC;
+ int kill = 0;
+ int ret;
+
+ filp->f_version = 0;
+
+ spin_lock(&inode->i_lock);
+ if (inode->i_pipe) {
+ pipe = inode->i_pipe;
+ pipe->files++;
+ spin_unlock(&inode->i_lock);
+ } else {
+ spin_unlock(&inode->i_lock);
+ pipe = alloc_pipe_info();
+ if (!pipe)
+ return -ENOMEM;
+ pipe->files = 1;
+ spin_lock(&inode->i_lock);
+ if (unlikely(inode->i_pipe)) {
+ inode->i_pipe->files++;
+ spin_unlock(&inode->i_lock);
+ free_pipe_info(pipe);
+ pipe = inode->i_pipe;
+ } else {
+ inode->i_pipe = pipe;
+ spin_unlock(&inode->i_lock);
+ }
+ }
+ filp->private_data = pipe;
+ /* OK, we have a pipe and it's pinned down */
+
+ __pipe_lock(pipe);
+
+ /* We can only do regular read/write on fifos */
+ filp->f_mode &= (FMODE_READ | FMODE_WRITE);
+
+ switch (filp->f_mode) {
+ case FMODE_READ:
+ /*
+ * O_RDONLY
+ * POSIX.1 says that O_NONBLOCK means return with the FIFO
+ * opened, even when there is no process writing the FIFO.
+ */
+ pipe->r_counter++;
+ if (pipe->readers++ == 0)
+ wake_up_partner(pipe);
+
+ if (!is_pipe && !pipe->writers) {
+ if ((filp->f_flags & O_NONBLOCK)) {
+ /* suppress POLLHUP until we have
+ * seen a writer */
+ filp->f_version = pipe->w_counter;
+ } else {
+ if (wait_for_partner(pipe, &pipe->w_counter))
+ goto err_rd;
+ }
+ }
+ break;
+
+ case FMODE_WRITE:
+ /*
+ * O_WRONLY
+ * POSIX.1 says that O_NONBLOCK means return -1 with
+ * errno=ENXIO when there is no process reading the FIFO.
+ */
+ ret = -ENXIO;
+ if (!is_pipe && (filp->f_flags & O_NONBLOCK) && !pipe->readers)
+ goto err;
+
+ pipe->w_counter++;
+ if (!pipe->writers++)
+ wake_up_partner(pipe);
+
+ if (!is_pipe && !pipe->readers) {
+ if (wait_for_partner(pipe, &pipe->r_counter))
+ goto err_wr;
+ }
+ break;
+
+ case FMODE_READ | FMODE_WRITE:
+ /*
+ * O_RDWR
+ * POSIX.1 leaves this case "undefined" when O_NONBLOCK is set.
+ * This implementation will NEVER block on a O_RDWR open, since
+ * the process can at least talk to itself.
+ */
+
+ pipe->readers++;
+ pipe->writers++;
+ pipe->r_counter++;
+ pipe->w_counter++;
+ if (pipe->readers == 1 || pipe->writers == 1)
+ wake_up_partner(pipe);
+ break;
+
+ default:
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /* Ok! */
+ __pipe_unlock(pipe);
+ return 0;
+
+err_rd:
+ if (!--pipe->readers)
+ wake_up_interruptible(&pipe->wait);
+ ret = -ERESTARTSYS;
+ goto err;
+
+err_wr:
+ if (!--pipe->writers)
+ wake_up_interruptible(&pipe->wait);
+ ret = -ERESTARTSYS;
+ goto err;
+
+err:
+ spin_lock(&inode->i_lock);
+ if (!--pipe->files) {
+ inode->i_pipe = NULL;
+ kill = 1;
+ }
+ spin_unlock(&inode->i_lock);
+ __pipe_unlock(pipe);
+ if (kill)
+ free_pipe_info(pipe);
+ return ret;
+}
+
+const struct file_operations pipefifo_fops = {
+ .open = fifo_open,
+ .llseek = no_llseek,
+ .read = do_sync_read,
+ .aio_read = pipe_read,
+ .write = do_sync_write,
+ .aio_write = pipe_write,
+ .poll = pipe_poll,
+ .unlocked_ioctl = pipe_ioctl,
+ .release = pipe_release,
+ .fasync = pipe_fasync,
+};
+
/*
* Allocate a new array of pipe buffers and copy the info over. Returns the
* pipe size if successful, or return -ERROR on error.
*/
struct pipe_inode_info *get_pipe_info(struct file *file)
{
- struct inode *i = file_inode(file);
-
- return S_ISFIFO(i->i_mode) ? i->i_pipe : NULL;
+ return file->f_op == &pipefifo_fops ? file->private_data : NULL;
}
long pipe_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
if (!pipe)
return -EBADF;
- mutex_lock(&pipe->inode->i_mutex);
+ __pipe_lock(pipe);
switch (cmd) {
case F_SETPIPE_SZ: {
}
out:
- mutex_unlock(&pipe->inode->i_mutex);
+ __pipe_unlock(pipe);
return ret;
}
projects / platform / adaptation / renesas_rcar / renesas_kernel.git / blobdiff