revert broken select optimizations

Cset exclude: torvalds@penguin.transmeta.com|ChangeSet|20020619003306|07760
Cset exclude: ak@muc.de|ChangeSet|20020618172743|19150

include/linux/poll.h

@@ -10,32 +10,13 @@
 #include <linux/mm.h>
 #include <asm/uaccess.h>
 
-#define POLL_INLINE_BYTES 256
-#define FAST_SELECT_MAX  128
-#define FAST_POLL_MAX    128
-#define POLL_INLINE_ENTRIES (1+(POLL_INLINE_BYTES / sizeof(struct poll_table_entry)))
-
-struct poll_table_entry {
-	struct file * filp;
-	wait_queue_t wait;
-	wait_queue_head_t * wait_address;
-};
-
-struct poll_table_page {
-	struct poll_table_page * next;
-	struct poll_table_entry * entry;
-	struct poll_table_entry entries[0];
-};
+struct poll_table_page;
 
 typedef struct poll_table_struct {
 	int error;
 	struct poll_table_page * table;
-	struct poll_table_page inline_page; 
-	struct poll_table_entry inline_table[POLL_INLINE_ENTRIES]; 
 } poll_table;
 
-#define POLL_INLINE_TABLE_LEN (sizeof(poll_table) - offsetof(poll_table, inline_page))
-
 extern void __pollwait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p);
 
 static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
@@ -49,7 +30,6 @@ static inline void poll_initwait(poll_table* pt)
 	pt->error = 0;
 	pt->table = NULL;
 }
-
 extern void poll_freewait(poll_table* pt);
 
 
@@ -69,6 +49,27 @@ typedef struct {
 #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 *ufdset, unsigned long *fdset)
+{
+	nr = FDS_BYTES(nr);
+	if (ufdset) {
+		int error;
+		error = verify_area(VERIFY_WRITE, ufdset, nr);
+		if (!error && __copy_from_user(fdset, ufdset, nr))
+			error = -EFAULT;
+		return error;
+	}
+	memset(fdset, 0, nr);
+	return 0;
+}
+
 static inline
 void set_fd_set(unsigned long nr, void *ufdset, unsigned long *fdset)
 {
@@ -76,6 +77,12 @@ void set_fd_set(unsigned long nr, void *ufdset, unsigned long *fdset)
 		__copy_to_user(ufdset, fdset, FDS_BYTES(nr));
 }
 
+static inline
+void zero_fd_set(unsigned long nr, unsigned long *fdset)
+{
+	memset(fdset, 0, FDS_BYTES(nr));
+}
+
 extern int do_select(int n, fd_set_bits *fds, long *timeout);
 
 #endif /* KERNEL */