[PATCH 5/14] multiple device *read* opens support

Michael Hunold
2003-10-08T13:35:58Z

- [DVB] allow multiple read device opens
diff -uNrwB --new-file xx-linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.h linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.h
--- xx-linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.h 2003-09-10 11:28:41.000000000 +0200
+++ linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.h 2003-08-25 12:16:12.000000000 +0200
@@ -55,12 +58,18 @@
struct dvb_device {
struct list_head list_head;
struct file_operations *fops;
+
+
+
struct dvb_adapter *adapter;
int type;
u32 id;

- int users;
+ /* in theory, 'users' can vanish now,
+ but I don't want to change too much now... */
+ int readers;
int writers;
+ int users;

/* don't really need those !? -- FIXME: use video_usercopy */
int (*kernel_ioctl)(struct inode *inode, struct file *file,
diff -uNrwB --new-file xx-linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.c linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.c
--- xx-linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.c 2003-09-10 11:29:20.000000000 +0200
+++ linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvbdev.c 2003-08-21 10:53:19.000000000 +0200
@@ -112,7 +121,11 @@
if (!dvbdev->users)
return -EBUSY;

- if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
+ if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
+ if (!dvbdev->readers)
+ return -EBUSY;
+ dvbdev->readers--;
+ } else {
if (!dvbdev->writers)
return -EBUSY;
dvbdev->writers--;
@@ -130,8 +143,11 @@
if (!dvbdev)
return -ENODEV;

- if ((file->f_flags & O_ACCMODE) != O_RDONLY)
+ if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
+ dvbdev->readers++;
+ } else {
dvbdev->writers++;
+ }

dvbdev->users++;
return 0;
diff -uNrwB --new-file xx-linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvb_frontend.c linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvb_frontend.c
--- xx-linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvb_frontend.c 2003-09-10 11:28:54.000000000 +0200
+++ linux-2.6.0-test5/drivers/media/dvb/dvb-core/dvb_frontend.c 2003-09-09 09:24:21.000000000 +0200
@@ -870,6 +886,7 @@
static const struct dvb_device dvbdev_template = {
.users = ~0,
.writers = 1,
+ .readers = (~0)-1,
.fops = &dvb_frontend_fops,
.kernel_ioctl = dvb_frontend_ioctl
};