June 2007 - Darwin-kernel - lists.apple.com

Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4
by Michael Smith 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On Jun 7, 2007, at 3:51 AM, Ratheesh Ramachandran wrote: Thanks Terry and Michael. Combining both your responses: There are, to the best of my recollection, no vnop_* functions of note. = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… - Kernel programs should not perform file operations using vop_* functions/structures (which is not possible on 10.4 anyway). - Kernel programs should perform file operations using the vnode_* functions (KPI) defined in sys/vnode.h Kernel code (there are no 'kernel programs' in the jargon) should as a general rule not perform "file operations" at all. Typically you will be operating on a vnode, which has previously been looked up by another function. - vnop_* functions are to be implemented by Filesystems, and the vnode_* functions (KPI) in turn call these. The VNOP_* functions are immediate wrappers around the functions implemented by filesystems, and exported by those filesystems in their VNOP export tables. This email sent to site_archiver(a)lists.apple.com

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Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4
by Ratheesh Ramachandran 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:Cc:MIME-Version:Content-Type:Message-ID; b=hdjnVVlhCZlo1lh4ZTtaAW2N5IOQzXNR0czyzFHq/W41ExelbV8EpGxfszszNp3tBj6SEgG+SehmLHZlPLCiMQ2ZECN4FoIc8Bwm/NYG1N/EG8ob1HvNSDV2kdC3/fV0hnpf8vcBTqnVA1aYVcUmaoyedGfajNtru/D6Q/61WLQ=; _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4
by Terry Lambert 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com -- Terry Is there a sample for the new usage available somewhere ? Thanks ! On Jun 6, 2007, at 11:59 AM, Ratheesh Ramachandran wrote: > Hi, > > I need to port some programs from an older version of Mac OS X to > 10.4. > > These programs use the "vop*" structures/functions from sys/vnode.h. > These are apparently no longer available in sys/vnode.h. > > Could anybody provide pointers/information on what has changed in > this area in 10.4 ? You need to include the kernel framework in your KEXT, and #include <sys/vnode_if.h>. -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… Those are for you to write an FS that gets called, not for you to make calls into an FS from kernel mode. The vfs_context_t is a contet on which the call may block, without fear of the credential reference inside it going away. It's effectively a credential reference and unreference, only automatically on your behalf, plus something that sits in the scheduler queue for any sleep or mutex acquisitions to happen on (you MUST treat a vfs_context_t as opaque!!!! This means you can't declare your own, and it means that if you do, some operation on the stace or in the name cache may take it as a promise that the data won't go out of scope, so if it does, you've instantly introduced a stack-smashing bug). If you are trying to do file I/O in the kernel using direct vop calls - don't! You're not going to get the VFS layer locking right. If you are being called by someone in user space, and you are legitimately consuming the VFS layer (e.g. you are a CODAFS implementaiton or something similar), then you will have a context because you will be the reference instance from a user space call into you (and you should look at the NFS server source code in the kernel for examples). On Jun 6, 2007, at 9:34 PM, Ratheesh Ramachandran wrote: So, are the vop*s now to be replaced by vnop*s ? The vnop* functions seem to require an additional argument -- vfs_context_t. ----- Original Message ---- From: Terry Lambert <tlambert(a)apple.com> To: Ratheesh Ramachandran <ratheesh_jakarta(a)yahoo.com> Cc: darwin-kernel(a)lists.apple.com Sent: Thursday, June 7, 2007 9:22:39 AM Subject: Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4 See /System/Library/Frameworks/Kernel.framework/Headers/sys/ vnode_if.h. Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for today's economy) at Yahoo! Games. This email sent to site_archiver(a)lists.apple.com

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Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4
by Michael Smith 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On Jun 6, 2007, at 9:34 PM, Ratheesh Ramachandran wrote: = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… So, are the vop*s now to be replaced by vnop*s ? The vnop* functions seem to require an additional argument -- vfs_context_t. Is there a sample for the new usage available somewhere ? As a general rule, you should not be calling the VNOP interfaces directly. Use the KPI interfaces in <sys/vnode.h> to operate on vnode_t's. The vfs_context_t encapsulates the identity and credential of the client of an operation. Typically you will be supplied with one by a higher layer in the kernel; if you don't have one *AND* the operation you are performing is on behalf of the current process, you can obtain one with vfs_context_create(NULL) - you must release it with vfs_context_rele() when you are done. Please note that the VFS KPI changes significantly in 10.4; you will not be able to just replace one set of calls with another - your code will probably require more in-depth changes, especially if you were doing file I/O by making direct VFS calls. This email sent to site_archiver(a)lists.apple.com

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Re: Compiling Darwin for MacBook Pro
by Michael Smith 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Are there any drivers required for the machine that are not part of the open source Darwin project? Yes. Having looked over the Darwin download page, I'm guessing that the network and hard disk drivers are kernel level modules, and the video driver for Darwin is a user-space component of the X11 distribution, correct? Drivers are not part of the kernel, per se. They, and their supporting libraries ("Families") are handled as loadable modules. = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… On Jun 6, 2007, at 12:12 PM, John Criswell wrote: Has anyone compiled a Darwin kernel and successfully run it on an Intel Mac laptop Yes. I should have been more explicit in my question. I assume this includes the Macbook Pro with Intel Core 2 Duo processor, correct? You can generally safely assume that a Darwin source release that post-dates the release date of your hardware will work. Yes. I assume that this is also true for the desktop machines. Correct? IONetworkingFamily, IOStorageFamily and their respective hardware- specific drivers are all built as kernel extensions, yes. I'm not familiar with X11 for Darwin. MacOS X video drivers are supplied in binary-only form and typically comprise several kernel extensions. Our project requires being able to do compiler analysis of the entire kernel source. I see. That may be a problem, but I imagine we can work around it. The Darwin kernel we build from the open source sources should be able to load and use these drivers, correct? Yes, that's correct. You will want to be careful about applying software updates to your system, as interface versions do occasionally get bumped, but for the most part you should not have any problems here. This email sent to site_archiver(a)lists.apple.com

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Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4
by Ratheesh Ramachandran 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:Cc:MIME-Version:Content-Type:Message-ID; b=Vr0ALAKg7uzJQHFfNmVbN8VpPHDL0sWaJHMqWUE9G2cKjXXILXo38hS21cQHhNBYquhUAkfhe5z0CzWWtVw6kBcEfH65mMIC3zbkHkjOMAWuHkwSJJhDHuFpWlSUnTxSmJy65AP61TiRHNdpDtY23TGJUgTsFa5t0vLMZiU8eqA=; _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Newbie question - missing vop* structures/functions in sys/vnode.h on 10.4
by Terry Lambert 07 Jun '07

07 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Hi, See /System/Library/Frameworks/Kernel.framework/Headers/sys/vnode_if.h. -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… On Jun 6, 2007, at 11:59 AM, Ratheesh Ramachandran wrote: I need to port some programs from an older version of Mac OS X to 10.4. These programs use the "vop*" structures/functions from sys/vnode.h. These are apparently no longer available in sys/vnode.h. Could anybody provide pointers/information on what has changed in this area in 10.4 ? You need to include the kernel framework in your KEXT, and #include <sys/vnode_if.h>. This email sent to site_archiver(a)lists.apple.com

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Re: Compiling Darwin for MacBook Pro
by Rick Macklem 06 Jun '07

06 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On Wed, 6 Jun 2007, John Criswell wrote: I assume that this is also true for the desktop machines. Correct? Good luck with it, rick _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… [good stuff snipped] I currently have a lab of 25 iMacs (Core 2 duo) running a kernel built from sources. The notes on what I do to build a kernel are in: ftp://ftp.cis.uoguelph.ca/pub/nfsv4/darwin-port/xnu-client.tar.gz in case you might find them useful. This email sent to site_archiver(a)lists.apple.com

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Re: Compiling Darwin for MacBook Pro
by Andreas Fink 06 Jun '07

06 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: Compiling Darwin for MacBook Pro
by John Criswell 06 Jun '07

06 Jun '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Organization: University of Illinois User-agent: Thunderbird 1.5.0.10 (X11/20070221) Michael Smith wrote: Thanks for your answers. I still have a few more questions below: > > On Jun 6, 2007, at 7:31 AM, John Criswell wrote: > >> Our research group is looking to buy a Macbook Pro (2.16 GHz Intel Core >> 2 Duo) for some research that we are doing. Our work involves >> modifications to the Darwin kernel. >> >> I'd like to gain some confidence that if we buy this machine, we can >> expect to compile our own kernels and have them work on the machine. > > Modulo the complexity of building the open-source kernel releases, > yes, this generally works. > >> Has anyone compiled a Darwin kernel and successfully run it on an Intel >> Mac laptop > > Yes. I should have been more explicit in my question. I assume this includes the Macbook Pro with Intel Core 2 Duo processor, correct? > >> Are there any drivers required for the machine that are not part of >> the open source >> Darwin project? > > Yes. I assume that this is also true for the desktop machines. Correct? Having looked over the Darwin download page, I'm guessing that the network and hard disk drivers are kernel level modules, and the video driver for Darwin is a user-space component of the X11 distribution, correct? > >> Our project requires being able to do compiler analysis of the entire >> kernel source. > > Drivers are not part of the kernel, per se. They, and their > supporting libraries ("Families") are handled as loadable modules. I see. That may be a problem, but I imagine we can work around it. The Darwin kernel we build from the open source sources should be able to load and use these drivers, correct? > > = Mike > > > -- John Criswell _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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