Date: Wed, 21 Sep 2011 10:05:25 +0400 From: =?UTF-8?B?Z2VvZmZyZXkgbGV2YW5k?= <geoffrey.levand@mail.ru> To: =?UTF-8?B?SGFucyBQZXR0ZXIgU2VsYXNreQ==?= <hselasky@c2i.net> Cc: freebsd-hackers@freebsd.org Subject: Re[2]: Sharing device driver between kernel and user space Message-ID: <E1R6Fvx-0005sO-00.geoffrey-levand-mail-ru@f177.mail.ru> In-Reply-To: <201109202202.19481.hselasky@c2i.net> References: <E1R65Aj-0003Fj-00.geoffrey-levand-mail-ru@f57.mail.ru> <201109202202.19481.hselasky@c2i.net>
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I think you misunderstood what i need. If i got it right then cuse4bsd allows user applications to create char devices, right ? I do not want to create character devices from user space. My VUART kernel module should provide the character device for user space. What i need is a way to synchronize access to VUART data between kernel and user space. The kernel device driver should provide 2 interfaces: one for user space (through char dev) and the other for kernel land. The problem is how to synchronize the access to VUART data between 2 lands because VUART cannot be shared by both simultaneously. 21 сентября 2011, 00:05 от Hans Petter Selasky <hselasky@c2i.net>: > On Tuesday 20 September 2011 20:35:57 geoffrey levand wrote: > > Currently i'm developing VUART device drivers for PS3 architecture. VUART > > is bi-directional FIFO queue between 2 logical partitions on PS3. I want > > to use the device in the kernel and user space. During system boot PS3 > > system has to read/write some data from/to the VUART devices and sometimes > > i want to access the device from user space , e.g. with character device > > driver by using read/write syscalls. The quuestion is what is the best > > solution to share the device between kernel and user lands. One solution i > > found would be to porohibit kernel access to the device as soon as a user > > application opens the corresponding character device. And allow it again > > when the application calls close syscall. The user space should have > > higher priority then the kernel. Are there any better solutions for this > > problem ? Forgot to mention that a VUART device cannot be accessed > > simultaneously by user land and the kernel. The VUART devices are used by > > PS3 management logical partition to provide different request/response > > services and event notification to other logical partitions. E.g. setting > > video mode or configuring audio outputs. > > > > Have you looked at cuse4bsd in ports/multimedia/cuse4bsd-kmod ? > > --HPS > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" >
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