1 files changed, 56 insertions, 79 deletions

diff --git a/include/linux/poll.h b/include/linux/poll.h
index c08386fb3e08..12bb18e8b978 100644
--- a/include/linux/poll.h
+++ b/include/linux/poll.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LINUX_POLL_H
 #define _LINUX_POLL_H
 
@@ -7,11 +8,10 @@
 #include <linux/wait.h>
 #include <linux/string.h>
 #include <linux/fs.h>
-#include <linux/sysctl.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 #include <uapi/linux/poll.h>
+#include <uapi/linux/eventpoll.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
@@ -21,38 +21,36 @@ extern struct ctl_table epoll_table[]; /* for sysctl */
 #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)
+#define DEFAULT_POLLMASK (EPOLLIN | EPOLLOUT | EPOLLRDNORM | EPOLLWRNORM)
 
 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.
+ * Do not touch the structure directly, use the access function
+ * poll_requested_events() instead.
  */
 typedef struct poll_table_struct {
 	poll_queue_proc _qproc;
-	unsigned long _key;
+	__poll_t _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)
+	if (p && p->_qproc) {
 		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;
+		/*
+		 * This memory barrier is paired in the wq_has_sleeper().
+		 * See the comment above prepare_to_wait(), we need to
+		 * ensure that subsequent tests in this thread can't be
+		 * reordered with __add_wait_queue() in _qproc() paths.
+		 */
+		smp_mb();
+	}
 }
 
 /*
@@ -61,21 +59,33 @@ static inline bool poll_does_not_wait(const poll_table *p)
  * 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)
+static inline __poll_t poll_requested_events(const poll_table *p)
 {
-	return p ? p->_key : ~0UL;
+	return p ? p->_key : ~(__poll_t)0;
 }
 
 static inline void init_poll_funcptr(poll_table *pt, poll_queue_proc qproc)
 {
 	pt->_qproc = qproc;
-	pt->_key   = ~0UL; /* all events enabled */
+	pt->_key   = ~(__poll_t)0; /* all events enabled */
+}
+
+static inline bool file_can_poll(struct file *file)
+{
+	return file->f_op->poll;
+}
+
+static inline __poll_t vfs_poll(struct file *file, struct poll_table_struct *pt)
+{
+	if (unlikely(!file->f_op->poll))
+		return DEFAULT_POLLMASK;
+	return file->f_op->poll(file, pt);
 }
 
 struct poll_table_entry {
 	struct file *filp;
-	unsigned long key;
-	wait_queue_t wait;
+	__poll_t key;
+	wait_queue_entry_t wait;
 	wait_queue_head_t *wait_address;
 };
 
@@ -94,71 +104,38 @@ struct poll_wqueues {
 
 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);
-}
+extern u64 select_estimate_accuracy(struct timespec64 *tv);
 
-/*
- * Scalable version of the fd_set.
- */
+#define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1)
 
-typedef struct {
-	unsigned long *in, *out, *ex;
-	unsigned long *res_in, *res_out, *res_ex;
-} fd_set_bits;
+extern int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
+			   fd_set __user *exp, struct timespec64 *end_time);
 
-/*
- * 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))
+extern int poll_select_set_timeout(struct timespec64 *to, time64_t sec,
+				   long nsec);
 
-/*
- * 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;
-}
+#define __MAP(v, from, to) \
+	(from < to ? (v & from) * (to/from) : (v & from) / (from/to))
 
-static inline unsigned long __must_check
-set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
+static inline __u16 mangle_poll(__poll_t val)
 {
-	if (ufdset)
-		return __copy_to_user(ufdset, fdset, FDS_BYTES(nr));
-	return 0;
+	__u16 v = (__force __u16)val;
+#define M(X) __MAP(v, (__force __u16)EPOLL##X, POLL##X)
+	return M(IN) | M(OUT) | M(PRI) | M(ERR) | M(NVAL) |
+		M(RDNORM) | M(RDBAND) | M(WRNORM) | M(WRBAND) |
+		M(HUP) | M(RDHUP) | M(MSG);
+#undef M
 }
 
-static inline
-void zero_fd_set(unsigned long nr, unsigned long *fdset)
+static inline __poll_t demangle_poll(u16 val)
 {
-	memset(fdset, 0, FDS_BYTES(nr));
+#define M(X) (__force __poll_t)__MAP(val, POLL##X, (__force __u16)EPOLL##X)
+	return M(IN) | M(OUT) | M(PRI) | M(ERR) | M(NVAL) |
+		M(RDNORM) | M(RDBAND) | M(WRNORM) | M(WRBAND) |
+		M(HUP) | M(RDHUP) | M(MSG);
+#undef M
 }
+#undef __MAP
 
-#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 */