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-rw-r--r--include/linux/pipe_fs_i.h59
1 files changed, 59 insertions, 0 deletions
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
new file mode 100644
index 00000000000..36725e7c02c
--- /dev/null
+++ b/include/linux/pipe_fs_i.h
@@ -0,0 +1,59 @@
+#ifndef _LINUX_PIPE_FS_I_H
+#define _LINUX_PIPE_FS_I_H
+
+#define PIPEFS_MAGIC 0x50495045
+
+#define PIPE_BUFFERS (16)
+
+struct pipe_buffer {
+ struct page *page;
+ unsigned int offset, len;
+ struct pipe_buf_operations *ops;
+};
+
+struct pipe_buf_operations {
+ int can_merge;
+ void * (*map)(struct file *, struct pipe_inode_info *, struct pipe_buffer *);
+ void (*unmap)(struct pipe_inode_info *, struct pipe_buffer *);
+ void (*release)(struct pipe_inode_info *, struct pipe_buffer *);
+};
+
+struct pipe_inode_info {
+ wait_queue_head_t wait;
+ unsigned int nrbufs, curbuf;
+ struct pipe_buffer bufs[PIPE_BUFFERS];
+ struct page *tmp_page;
+ unsigned int start;
+ unsigned int readers;
+ unsigned int writers;
+ unsigned int waiting_writers;
+ unsigned int r_counter;
+ unsigned int w_counter;
+ struct fasync_struct *fasync_readers;
+ struct fasync_struct *fasync_writers;
+};
+
+/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
+ memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
+#define PIPE_SIZE PAGE_SIZE
+
+#define PIPE_SEM(inode) (&(inode).i_sem)
+#define PIPE_WAIT(inode) (&(inode).i_pipe->wait)
+#define PIPE_BASE(inode) ((inode).i_pipe->base)
+#define PIPE_START(inode) ((inode).i_pipe->start)
+#define PIPE_LEN(inode) ((inode).i_pipe->len)
+#define PIPE_READERS(inode) ((inode).i_pipe->readers)
+#define PIPE_WRITERS(inode) ((inode).i_pipe->writers)
+#define PIPE_WAITING_WRITERS(inode) ((inode).i_pipe->waiting_writers)
+#define PIPE_RCOUNTER(inode) ((inode).i_pipe->r_counter)
+#define PIPE_WCOUNTER(inode) ((inode).i_pipe->w_counter)
+#define PIPE_FASYNC_READERS(inode) (&((inode).i_pipe->fasync_readers))
+#define PIPE_FASYNC_WRITERS(inode) (&((inode).i_pipe->fasync_writers))
+
+/* Drop the inode semaphore and wait for a pipe event, atomically */
+void pipe_wait(struct inode * inode);
+
+struct inode* pipe_new(struct inode* inode);
+void free_pipe_info(struct inode* inode);
+
+#endif