obj-y := open.o read_write.o file_table.o super.o \
char_dev.o stat.o exec.o pipe.o namei.o fcntl.o \
- ioctl.o readdir.o select.o fifo.o dcache.o inode.o \
+ ioctl.o readdir.o select.o dcache.o inode.o \
attr.o bad_inode.o file.o filesystems.o namespace.o \
seq_file.o xattr.o libfs.o fs-writeback.o \
pnode.o drop_caches.o splice.o sync.o utimes.o \
+++ /dev/null
-/*
- * linux/fs/fifo.c
- *
- * written by Paul H. Hargrove
- *
- * Fixes:
- * 10-06-1999, AV: fixed OOM handling in fifo_open(), moved
- * initialization there, switched to external
- * allocation of pipe_inode_info.
- */
-
-#include <linux/mm.h>
-#include <linux/fs.h>
-#include <linux/sched.h>
-#include <linux/pipe_fs_i.h>
-
-static int wait_for_partner(struct inode* inode, unsigned int *cnt)
-{
- int cur = *cnt;
-
- while (cur == *cnt) {
- pipe_wait(inode->i_pipe);
- if (signal_pending(current))
- break;
- }
- return cur == *cnt ? -ERESTARTSYS : 0;
-}
-
-static void wake_up_partner(struct inode* inode)
-{
- wake_up_interruptible(&inode->i_pipe->wait);
-}
-
-static int fifo_open(struct inode *inode, struct file *filp)
-{
- struct pipe_inode_info *pipe;
- int ret;
-
- mutex_lock(&inode->i_mutex);
- pipe = inode->i_pipe;
- if (!pipe) {
- ret = -ENOMEM;
- pipe = alloc_pipe_info(inode);
- if (!pipe)
- goto err_nocleanup;
- inode->i_pipe = pipe;
- }
- filp->f_version = 0;
-
- /* 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.
- */
- filp->f_op = &read_pipefifo_fops;
- pipe->r_counter++;
- if (pipe->readers++ == 0)
- wake_up_partner(inode);
-
- if (!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(inode, &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 ((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 (wait_for_partner(inode, &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.
- */
- filp->f_op = &rdwr_pipefifo_fops;
-
- pipe->readers++;
- pipe->writers++;
- pipe->r_counter++;
- pipe->w_counter++;
- if (pipe->readers == 1 || pipe->writers == 1)
- wake_up_partner(inode);
- break;
-
- default:
- ret = -EINVAL;
- goto err;
- }
-
- /* Ok! */
- mutex_unlock(&inode->i_mutex);
- 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:
- if (!pipe->readers && !pipe->writers)
- free_pipe_info(inode);
-
-err_nocleanup:
- mutex_unlock(&inode->i_mutex);
- 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,
-};
return sys_pipe2(fildes, 0);
}
+static int wait_for_partner(struct inode* inode, unsigned int *cnt)
+{
+ int cur = *cnt;
+
+ while (cur == *cnt) {
+ pipe_wait(inode->i_pipe);
+ if (signal_pending(current))
+ break;
+ }
+ return cur == *cnt ? -ERESTARTSYS : 0;
+}
+
+static void wake_up_partner(struct inode* inode)
+{
+ wake_up_interruptible(&inode->i_pipe->wait);
+}
+
+static int fifo_open(struct inode *inode, struct file *filp)
+{
+ struct pipe_inode_info *pipe;
+ int ret;
+
+ mutex_lock(&inode->i_mutex);
+ pipe = inode->i_pipe;
+ if (!pipe) {
+ ret = -ENOMEM;
+ pipe = alloc_pipe_info(inode);
+ if (!pipe)
+ goto err_nocleanup;
+ inode->i_pipe = pipe;
+ }
+ filp->f_version = 0;
+
+ /* 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.
+ */
+ filp->f_op = &read_pipefifo_fops;
+ pipe->r_counter++;
+ if (pipe->readers++ == 0)
+ wake_up_partner(inode);
+
+ if (!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(inode, &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 ((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 (wait_for_partner(inode, &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.
+ */
+ filp->f_op = &rdwr_pipefifo_fops;
+
+ pipe->readers++;
+ pipe->writers++;
+ pipe->r_counter++;
+ pipe->w_counter++;
+ if (pipe->readers == 1 || pipe->writers == 1)
+ wake_up_partner(inode);
+ break;
+
+ default:
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /* Ok! */
+ mutex_unlock(&inode->i_mutex);
+ 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:
+ if (!pipe->readers && !pipe->writers)
+ free_pipe_info(inode);
+
+err_nocleanup:
+ mutex_unlock(&inode->i_mutex);
+ 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,
+};
+
/*
* Allocate a new array of pipe buffers and copy the info over. Returns the
* pipe size if successful, or return -ERROR on error.
projects / platform / kernel / linux-stable.git / commitdiff