I've replaced simple_select in v4l1-compat.c: the current implementation
is just way to ugly to remain in the kernel.
Unfortunately I don't have a test setup.
Could someone test that the patch doesn't break the compatibility layer?
The patch is against 2.5.58.
Thanks,
--
Manfred
--- 2.5/drivers/media/video/v4l1-compat.c 2003-01-15 20:30:20.000000000 +0100
+++ build-2.5/drivers/media/video/v4l1-compat.c 2003-01-16 23:50:26.000000000 +0100
@@ -199,66 +199,33 @@
return palette;
}
-/* Do an 'in' (wait for input) select on a single file descriptor */
-/* This stuff plaigarized from linux/fs/select.c */
-#define __FD_IN(fds, n) (fds->in + n)
-#define BIT(i) (1UL << ((i)&(__NFDBITS-1)))
-#define SET(i,m) (*(m) |= (i))
-extern int do_select(int n, fd_set_bits *fds, long *timeout);
-
-
static int
simple_select(struct file *file)
{
- fd_set_bits fds;
- char *bits;
- long timeout;
- int i, fd, n, ret, size;
-
- for (i = 0; i < current->files->max_fds; ++i)
- if (file == current->files->fd[i])
- break;
- if (i == current->files->max_fds)
- return -EINVAL;
- fd = i;
- n = fd + 1;
-
- timeout = MAX_SCHEDULE_TIMEOUT;
- /*
- * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
- * since we used fdset we need to allocate memory in units of
- * long-words.
- */
- ret = -ENOMEM;
- size = FDS_BYTES(n);
- bits = kmalloc(6 * size, GFP_KERNEL);
- if (!bits)
- goto out_nofds;
- fds.in = (unsigned long *) bits;
- fds.out = (unsigned long *) (bits + size);
- fds.ex = (unsigned long *) (bits + 2*size);
- fds.res_in = (unsigned long *) (bits + 3*size);
- fds.res_out = (unsigned long *) (bits + 4*size);
- fds.res_ex = (unsigned long *) (bits + 5*size);
-
- /* All zero except our one file descriptor bit, for input */
- memset(bits, 0, 6 * size);
- SET(BIT(fd), __FD_IN((&fds), fd / __NFDBITS));
-
- ret = do_select(n, &fds, &timeout);
-
- if (ret < 0)
- goto out;
- if (!ret) {
- ret = -ERESTARTNOHAND;
- if (signal_pending(current))
- goto out;
- ret = 0;
- }
-out:
- kfree(bits);
-out_nofds:
- return ret;
+ int retval = 1;
+ struct poll_wqueues wait_table;
+ poll_table *table;
+
+ poll_initwait(&wait_table);
+ table = &wait_table.pt;
+ for (;;) {
+ int mask;
+ set_current_state(TASK_INTERRUPTIBLE);
+ mask = POLLIN;
+ if (file->f_op && file->f_op->poll)
+ mask = file->f_op->poll(file, table);
+ if (mask & POLLIN)
+ break;
+ table = NULL;
+ if (signal_pending(current)) {
+ retval = -ERESTARTSYS;
+ break;
+ }
+ schedule();
+ }
+ current->state = TASK_RUNNING;
+ poll_freewait(&wait_table);
+ return retval;
}
static int count_inputs(struct inode *inode,
