Return-Path: Date: Mon, 17 Feb 2014 16:01:25 -0300 From: Lucas De Marchi To: Marcel Holtmann CC: Lucas De Marchi , "bluez mailin list (linux-bluetooth@vger.kernel.org)" , , Subject: Re: [PATCH] Bluetooth: allocate static minor for vhci Message-ID: <20140217190125.GA1851@intel.com> References: <1392649945-2338-1-git-send-email-lucas.demarchi@intel.com> <6D43DF5A-CFA0-4867-8518-ECDA167BDB71@holtmann.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" In-Reply-To: <6D43DF5A-CFA0-4867-8518-ECDA167BDB71@holtmann.org> List-ID: [ CC'ing Kay and Greg ] On Mon, Feb 17, 2014 at 08:34:32AM -0800, Marcel Holtmann wrote: > Hi Lucas, > > > Commit bfacbb9 (Bluetooth: Use devname:vhci module alias for virtual HCI > > driver) added the module alias to hci_vhci module so it's possible to > > create the /dev/vhci node. However creating an alias without > > specifying the minor doesn't allow us to create the node ahead, > > triggerring module auto-load when it's first accessed. > > > > Starting with depmod from kmod 16 we started to warn if there's a > > devname alias without specifying the major and minor. > > > > Let's do the same done for uhid, kvm, fuse and others, specifying a > > fixed minor. In systems with systemd as the init the following will > > happen: on early boot systemd will call "kmod static-nodes" to read > > /lib/modules/$(uname -r)/modules.devname and then create the nodes. When > > first accessed these "dead" nodes will trigger the module loading. > > > > Signed-off-by: Lucas De Marchi > > --- > > drivers/bluetooth/hci_vhci.c | 3 ++- > > include/linux/miscdevice.h | 1 + > > 2 files changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/bluetooth/hci_vhci.c b/drivers/bluetooth/hci_vhci.c > > index 1ef6990..add1c6a 100644 > > --- a/drivers/bluetooth/hci_vhci.c > > +++ b/drivers/bluetooth/hci_vhci.c > > @@ -359,7 +359,7 @@ static const struct file_operations vhci_fops = { > > static struct miscdevice vhci_miscdev= { > > .name = "vhci", > > .fops = &vhci_fops, > > - .minor = MISC_DYNAMIC_MINOR, > > + .minor = VHCI_MINOR, > > }; > > > > static int __init vhci_init(void) > > @@ -385,3 +385,4 @@ MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION); > > MODULE_VERSION(VERSION); > > MODULE_LICENSE("GPL"); > > MODULE_ALIAS("devname:vhci"); > > +MODULE_ALIAS_MISCDEV(VHCI_MINOR); > > diff --git a/include/linux/miscdevice.h b/include/linux/miscdevice.h > > index 3737f72..846a317 100644 > > --- a/include/linux/miscdevice.h > > +++ b/include/linux/miscdevice.h > > @@ -48,6 +48,7 @@ > > #define LOOP_CTRL_MINOR 237 > > #define VHOST_NET_MINOR 238 > > #define UHID_MINOR 239 > > +#define VHCI_MINOR 240 > > #define MISC_DYNAMIC_MINOR 255 > > you have read Documentation/devices.txt where it states that 240-254 is reserved for local use. I haven't seen that. So, are we out of minors or.. can I use e.g. 142, 129 or the ones below 128? Kay? Greg? -- Lucas De Marchi