diff options
Diffstat (limited to 'include/linux/pipe_fs_i.h')
| -rw-r--r-- | include/linux/pipe_fs_i.h | 59 |
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 |