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authorAl Viro <viro@zeniv.linux.org.uk>2013-03-12 09:58:10 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2013-04-09 14:12:58 -0400
commit599a0ac14e065b7c08471ef2e75a504b7dec9267 (patch)
tree21f9caef768eb84dad3ce19f76e646af0a5e4dfa /fs/pipe.c
parentf776c738883bc949e654568a565aee5a7d3fe133 (diff)
downloadop-kernel-dev-599a0ac14e065b7c08471ef2e75a504b7dec9267.zip
op-kernel-dev-599a0ac14e065b7c08471ef2e75a504b7dec9267.tar.gz
pipe: fold file_operations instances in one
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/pipe.c')
-rw-r--r--fs/pipe.c221
1 files changed, 32 insertions, 189 deletions
diff --git a/fs/pipe.c b/fs/pipe.c
index aed80c2..099ac3b 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -25,6 +25,8 @@
#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
@@ -662,19 +664,6 @@ out:
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);
@@ -734,14 +723,16 @@ pipe_poll(struct file *filp, poll_table *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;
mutex_lock(&inode->i_mutex);
pipe = inode->i_pipe;
- pipe->readers -= decr;
- pipe->writers -= decw;
+ 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);
@@ -756,174 +747,25 @@ pipe_release(struct inode *inode, int decr, int decw)
}
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;
-
- mutex_lock(&inode->i_mutex);
- retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_writers);
- mutex_unlock(&inode->i_mutex);
-
- return retval;
-}
-
-
-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;
+ int retval = 0;
mutex_lock(&inode->i_mutex);
- retval = fasync_helper(fd, filp, on, &pipe->fasync_readers);
- if (retval >= 0) {
+ 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);
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 *pipe;
@@ -996,7 +838,7 @@ static struct inode * get_pipe_inode(void)
inode->i_pipe = pipe;
pipe->readers = pipe->writers = 1;
- inode->i_fop = &rdwr_pipefifo_fops;
+ inode->i_fop = &pipefifo_fops;
/*
* Mark the inode dirty from the very beginning,
@@ -1039,13 +881,13 @@ int create_pipe_files(struct file **res, int flags)
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));
- 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;
@@ -1164,6 +1006,7 @@ static void wake_up_partner(struct inode* inode)
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 ret;
mutex_lock(&inode->i_mutex);
@@ -1187,12 +1030,11 @@ static int fifo_open(struct inode *inode, struct file *filp)
* POSIX.1 says that O_NONBLOCK means return with the FIFO
* opened, even when there is no process writing the FIFO.
*/
- filp->f_op = &read_pipefifo_fops;
pipe->r_counter++;
if (pipe->readers++ == 0)
wake_up_partner(inode);
- if (!pipe->writers) {
+ if (!is_pipe && !pipe->writers) {
if ((filp->f_flags & O_NONBLOCK)) {
/* suppress POLLHUP until we have
* seen a writer */
@@ -1211,15 +1053,14 @@ static int fifo_open(struct inode *inode, struct file *filp)
* errno=ENXIO when there is no process reading the FIFO.
*/
ret = -ENXIO;
- if ((filp->f_flags & O_NONBLOCK) && !pipe->readers)
+ if (!is_pipe && (filp->f_flags & O_NONBLOCK) && !pipe->readers)
goto err;
- filp->f_op = &write_pipefifo_fops;
pipe->w_counter++;
if (!pipe->writers++)
wake_up_partner(inode);
- if (!pipe->readers) {
+ if (!is_pipe && !pipe->readers) {
if (wait_for_partner(inode, &pipe->r_counter))
goto err_wr;
}
@@ -1232,7 +1073,6 @@ static int fifo_open(struct inode *inode, struct file *filp)
* This implementation will NEVER block on a O_RDWR open, since
* the process can at least talk to itself.
*/
- filp->f_op = &rdwr_pipefifo_fops;
pipe->readers++;
pipe->writers++;
@@ -1272,14 +1112,17 @@ err_nocleanup:
return ret;
}
-/*
- * Dummy default file-operations: the only thing this does
- * is contain the open that then fills in the correct operations
- * depending on the access mode of the file...
- */
-const struct file_operations def_fifo_fops = {
- .open = fifo_open, /* will set read_ or write_pipefifo_fops */
- .llseek = noop_llseek,
+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,
};
/*
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