[PATCH] epoll bits 0.59 ...

- Finalized the interface by :

        * Having an epoll_event structure instead of using the pollfd
        * Adding a 64 bit opaque data member to the epoll_event structure
        * Removing the "fd" member from the epoll_event structure
        * Removing the "revents" member to leave space for a unique 32 bit
                "events" member

- Fixes the problem where, due the new callback'd wake_up() mechanism
        loops might be generated by bringing deadlock or stack blow ups.
        In fact a user could create a cycle by adding epoll fds inside
        other epoll fds. The patch solves the problem by either :

        * Moving the wake_up() call done on the poll wait queue head,
                outside the locked region
        * Implementing a new safe wake up function for the poll wait queue
                head

- Some variable renaming

- Changed __NR_sys_epoll_* to __NR_epoll_* ( Hanna Linder )

- Blocked the add operation of an epoll file descriptor inside itself

- Comments added/fixed

arch/um/kernel/sys_call_table.c

@@ -485,9 +485,9 @@ syscall_handler_t *sys_call_table[] = {
 	[ __NR_free_hugepages ] = sys_ni_syscall,
 	[ __NR_exit_group ] = sys_exit_group,
 	[ __NR_lookup_dcookie ] = sys_lookup_dcookie,
-	[ __NR_sys_epoll_create ] = sys_epoll_create,
-	[ __NR_sys_epoll_ctl ] = sys_epoll_ctl,
-	[ __NR_sys_epoll_wait ] = sys_epoll_wait,
+	[ __NR_epoll_create ] = sys_epoll_create,
+	[ __NR_epoll_ctl ] = sys_epoll_ctl,
+	[ __NR_epoll_wait ] = sys_epoll_wait,
         [ __NR_remap_file_pages ] = sys_remap_file_pages,
 
 	ARCH_SYSCALLS

include/asm-i386/unistd.h

@@ -259,9 +259,9 @@
 #define __NR_free_hugepages	251
 #define __NR_exit_group		252
 #define __NR_lookup_dcookie	253
-#define __NR_sys_epoll_create	254
-#define __NR_sys_epoll_ctl	255
-#define __NR_sys_epoll_wait	256
+#define __NR_epoll_create	254
+#define __NR_epoll_ctl		255
+#define __NR_epoll_wait		256
 #define __NR_remap_file_pages	257
 #define __NR_set_tid_address	258
 

include/asm-ppc/unistd.h

@@ -240,9 +240,9 @@
 #define __NR_free_hugepages	233
 #define __NR_exit_group		234
 #define __NR_lookup_dcookie	235
-#define __NR_sys_epoll_create	236
-#define __NR_sys_epoll_ctl	237
-#define __NR_sys_epoll_wait	238
+#define __NR_epoll_create	236
+#define __NR_epoll_ctl		237
+#define __NR_epoll_wait		238
 #define __NR_remap_file_pages	239
 
 #define __NR(n)	#n

include/linux/eventpoll.h

@@ -16,22 +16,25 @@
 
 
 /* Valid opcodes to issue to sys_epoll_ctl() */
-#define EP_CTL_ADD 1
-#define EP_CTL_DEL 2
-#define EP_CTL_MOD 3
+#define EPOLL_CTL_ADD 1
+#define EPOLL_CTL_DEL 2
+#define EPOLL_CTL_MOD 3
 
+struct epoll_event {
+	__u32 events;
+	__u64 data;
+};
 
 #ifdef __KERNEL__
 
 /* Forward declarations to avoid compiler errors */
 struct file;
-struct pollfd;
 
 
 /* Kernel space functions implementing the user space "epoll" API */
 asmlinkage int sys_epoll_create(int size);
-asmlinkage int sys_epoll_ctl(int epfd, int op, int fd, unsigned int events);
-asmlinkage int sys_epoll_wait(int epfd, struct pollfd *events, int maxevents,
+asmlinkage int sys_epoll_ctl(int epfd, int op, int fd, struct epoll_event *event);
+asmlinkage int sys_epoll_wait(int epfd, struct epoll_event *events, int maxevents,
 			      int timeout);
 
 /* Used to initialize the epoll bits inside the "struct file" */