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-rw-r--r--kernel/include/linux/poll.h164
1 files changed, 164 insertions, 0 deletions
diff --git a/kernel/include/linux/poll.h b/kernel/include/linux/poll.h
new file mode 100644
index 000000000..c08386fb3
--- /dev/null
+++ b/kernel/include/linux/poll.h
@@ -0,0 +1,164 @@
+#ifndef _LINUX_POLL_H
+#define _LINUX_POLL_H
+
+
+#include <linux/compiler.h>
+#include <linux/ktime.h>
+#include <linux/wait.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/sysctl.h>
+#include <asm/uaccess.h>
+#include <uapi/linux/poll.h>
+
+extern struct ctl_table epoll_table[]; /* for sysctl */
+/* ~832 bytes of stack space used max in sys_select/sys_poll before allocating
+ additional memory. */
+#define MAX_STACK_ALLOC 832
+#define FRONTEND_STACK_ALLOC 256
+#define SELECT_STACK_ALLOC FRONTEND_STACK_ALLOC
+#define POLL_STACK_ALLOC FRONTEND_STACK_ALLOC
+#define WQUEUES_STACK_ALLOC (MAX_STACK_ALLOC - FRONTEND_STACK_ALLOC)
+#define N_INLINE_POLL_ENTRIES (WQUEUES_STACK_ALLOC / sizeof(struct poll_table_entry))
+
+#define DEFAULT_POLLMASK (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)
+
+struct poll_table_struct;
+
+/*
+ * structures and helpers for f_op->poll implementations
+ */
+typedef void (*poll_queue_proc)(struct file *, wait_queue_head_t *, struct poll_table_struct *);
+
+/*
+ * Do not touch the structure directly, use the access functions
+ * poll_does_not_wait() and poll_requested_events() instead.
+ */
+typedef struct poll_table_struct {
+ poll_queue_proc _qproc;
+ unsigned long _key;
+} poll_table;
+
+static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
+{
+ if (p && p->_qproc && wait_address)
+ p->_qproc(filp, wait_address, p);
+}
+
+/*
+ * Return true if it is guaranteed that poll will not wait. This is the case
+ * if the poll() of another file descriptor in the set got an event, so there
+ * is no need for waiting.
+ */
+static inline bool poll_does_not_wait(const poll_table *p)
+{
+ return p == NULL || p->_qproc == NULL;
+}
+
+/*
+ * Return the set of events that the application wants to poll for.
+ * This is useful for drivers that need to know whether a DMA transfer has
+ * to be started implicitly on poll(). You typically only want to do that
+ * if the application is actually polling for POLLIN and/or POLLOUT.
+ */
+static inline unsigned long poll_requested_events(const poll_table *p)
+{
+ return p ? p->_key : ~0UL;
+}
+
+static inline void init_poll_funcptr(poll_table *pt, poll_queue_proc qproc)
+{
+ pt->_qproc = qproc;
+ pt->_key = ~0UL; /* all events enabled */
+}
+
+struct poll_table_entry {
+ struct file *filp;
+ unsigned long key;
+ wait_queue_t wait;
+ wait_queue_head_t *wait_address;
+};
+
+/*
+ * Structures and helpers for select/poll syscall
+ */
+struct poll_wqueues {
+ poll_table pt;
+ struct poll_table_page *table;
+ struct task_struct *polling_task;
+ int triggered;
+ int error;
+ int inline_index;
+ struct poll_table_entry inline_entries[N_INLINE_POLL_ENTRIES];
+};
+
+extern void poll_initwait(struct poll_wqueues *pwq);
+extern void poll_freewait(struct poll_wqueues *pwq);
+extern int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
+ ktime_t *expires, unsigned long slack);
+extern long select_estimate_accuracy(struct timespec *tv);
+
+
+static inline int poll_schedule(struct poll_wqueues *pwq, int state)
+{
+ return poll_schedule_timeout(pwq, state, NULL, 0);
+}
+
+/*
+ * Scalable version of the fd_set.
+ */
+
+typedef struct {
+ unsigned long *in, *out, *ex;
+ unsigned long *res_in, *res_out, *res_ex;
+} fd_set_bits;
+
+/*
+ * How many longwords for "nr" bits?
+ */
+#define FDS_BITPERLONG (8*sizeof(long))
+#define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG)
+#define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long))
+
+/*
+ * We do a VERIFY_WRITE here even though we are only reading this time:
+ * we'll write to it eventually..
+ *
+ * Use "unsigned long" accesses to let user-mode fd_set's be long-aligned.
+ */
+static inline
+int get_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
+{
+ nr = FDS_BYTES(nr);
+ if (ufdset)
+ return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0;
+
+ memset(fdset, 0, nr);
+ return 0;
+}
+
+static inline unsigned long __must_check
+set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
+{
+ if (ufdset)
+ return __copy_to_user(ufdset, fdset, FDS_BYTES(nr));
+ return 0;
+}
+
+static inline
+void zero_fd_set(unsigned long nr, unsigned long *fdset)
+{
+ memset(fdset, 0, FDS_BYTES(nr));
+}
+
+#define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1)
+
+extern int do_select(int n, fd_set_bits *fds, struct timespec *end_time);
+extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds,
+ struct timespec *end_time);
+extern int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
+ fd_set __user *exp, struct timespec *end_time);
+
+extern int poll_select_set_timeout(struct timespec *to, long sec, long nsec);
+
+#endif /* _LINUX_POLL_H */