1 #ifndef _LINUX_POLL_H 2 #define _LINUX_POLL_H 3 4 #include <asm/poll.h> 5 6 #ifdef __KERNEL__ 7 8 #include <linux/compiler.h> 9 #include <linux/wait.h> 10 #include <linux/string.h> 11 #include <linux/fs.h> 12 #include <linux/sched.h> 13 #include <asm/uaccess.h> 14 15 /* ~832 bytes of stack space used max in sys_select/sys_poll before allocating 16 additional memory. */ 17 #define MAX_STACK_ALLOC 832 18 #define FRONTEND_STACK_ALLOC 256 19 #define SELECT_STACK_ALLOC FRONTEND_STACK_ALLOC 20 #define POLL_STACK_ALLOC FRONTEND_STACK_ALLOC 21 #define WQUEUES_STACK_ALLOC (MAX_STACK_ALLOC - FRONTEND_STACK_ALLOC) 22 #define N_INLINE_POLL_ENTRIES (WQUEUES_STACK_ALLOC / sizeof(struct poll_table_entry)) 23 24 #define DEFAULT_POLLMASK (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM) 25 26 struct poll_table_struct; 27 28 /* 29 * structures and helpers for f_op->poll implementations 30 */ 31 typedef void (*poll_queue_proc)(struct file *, wait_queue_head_t *, struct poll_table_struct *); 32 33 typedef struct poll_table_struct { 34 poll_queue_proc qproc; 35 } poll_table; 36 37 static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p) 38 { 39 if (p && wait_address) 40 p->qproc(filp, wait_address, p); 41 } 42 43 static inline void init_poll_funcptr(poll_table *pt, poll_queue_proc qproc) 44 { 45 pt->qproc = qproc; 46 } 47 48 struct poll_table_entry { 49 struct file *filp; 50 wait_queue_t wait; 51 wait_queue_head_t *wait_address; 52 }; 53 54 /* 55 * Structures and helpers for sys_poll/sys_poll 56 */ 57 struct poll_wqueues { 58 poll_table pt; 59 struct poll_table_page *table; 60 struct task_struct *polling_task; 61 int triggered; 62 int error; 63 int inline_index; 64 struct poll_table_entry inline_entries[N_INLINE_POLL_ENTRIES]; 65 }; 66 67 extern void poll_initwait(struct poll_wqueues *pwq); 68 extern void poll_freewait(struct poll_wqueues *pwq); 69 extern int poll_schedule_timeout(struct poll_wqueues *pwq, int state, 70 ktime_t *expires, unsigned long slack); 71 72 static inline int poll_schedule(struct poll_wqueues *pwq, int state) 73 { 74 return poll_schedule_timeout(pwq, state, NULL, 0); 75 } 76 77 /* 78 * Scaleable version of the fd_set. 79 */ 80 81 typedef struct { 82 unsigned long *in, *out, *ex; 83 unsigned long *res_in, *res_out, *res_ex; 84 } fd_set_bits; 85 86 /* 87 * How many longwords for "nr" bits? 88 */ 89 #define FDS_BITPERLONG (8*sizeof(long)) 90 #define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG) 91 #define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long)) 92 93 /* 94 * We do a VERIFY_WRITE here even though we are only reading this time: 95 * we'll write to it eventually.. 96 * 97 * Use "unsigned long" accesses to let user-mode fd_set's be long-aligned. 98 */ 99 static inline 100 int get_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset) 101 { 102 nr = FDS_BYTES(nr); 103 if (ufdset) 104 return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0; 105 106 memset(fdset, 0, nr); 107 return 0; 108 } 109 110 static inline unsigned long __must_check 111 set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset) 112 { 113 if (ufdset) 114 return __copy_to_user(ufdset, fdset, FDS_BYTES(nr)); 115 return 0; 116 } 117 118 static inline 119 void zero_fd_set(unsigned long nr, unsigned long *fdset) 120 { 121 memset(fdset, 0, FDS_BYTES(nr)); 122 } 123 124 #define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1) 125 126 extern int do_select(int n, fd_set_bits *fds, struct timespec *end_time); 127 extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds, 128 struct timespec *end_time); 129 extern int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, 130 fd_set __user *exp, struct timespec *end_time); 131 132 extern int poll_select_set_timeout(struct timespec *to, long sec, long nsec); 133 134 #endif /* KERNEL */ 135 136 #endif /* _LINUX_POLL_H */ 137