May 2005 - Darwin-kernel - lists.apple.com

mbuf_outbound_finalize and TCP_SUM16 hardware checksum
by Anton Kuzmin 03 May '05

03 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com User-agent: Mozilla Thunderbird 1.0 (Windows/20041206) Hello, Regards, Anton _______________________________________________ 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.… I wonder if this is a known problem (or me missing something obvious) - outgoing TCP packets to be sent via the built-in ethernet device (GMace) appear to have only MBUF_CSUM_REQ_SUM16 hardware checksum request flag set as seen by an output KPI interface filter, which needs to modify the packet and therefore calls mbuf_outbound_finalize to do the delayed checksums. But from the xnu source it seems that this function has no knowledge of this flag and does nothing to calculate the checksum. This email sent to site_archiver(a)lists.apple.com

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Re: blocking writes and tiger update
by Nicolas Berloquin 03 May '05

03 May '05

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: syscall implementation
by Bijoy Thomas 03 May '05

03 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Regards, Bijoy Thomas. On May 2, 2005, at 10:00 PM, Justin Walker wrote: On May 2, 2005, at 18:45, Bijoy Thomas wrote: Use 'cscope' on the kernel and look for "syscall" as a "C symbol". Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large Institute for General Semantics -------- It's not whether you win or lose... It's whether *I* win or lose. -------- This email sent to bijoyjth(a)bluebottle.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.… Thanks for the reply. I just came across an article on it. http://dom.neopoleon.com/permalink.aspx/4e48d9dd-4c28-4b89-a8e5 -8cb158da44c3 How are system calls implemented in Mac OS X? Are they implemented as software interrupts as in Linux? How does the argument passing from user space to kernel space take place? Any info/docs/links would be greatly appreciated. _______________________________________________ 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/ bijoyjth%40bluebottle.com This email sent to site_archiver(a)lists.apple.com

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Re: syscall implementation
by Justin Walker 03 May '05

03 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On May 2, 2005, at 18:45, Bijoy Thomas wrote: Use 'cscope' on the kernel and look for "syscall" as a "C symbol". Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large Institute for General Semantics -------- It's not whether you win or lose... It's whether *I* win or lose. -------- _______________________________________________ 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.… How are system calls implemented in Mac OS X? Are they implemented as software interrupts as in Linux? How does the argument passing from user space to kernel space take place? Any info/docs/links would be greatly appreciated. This email sent to site_archiver(a)lists.apple.com

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syscall implementation
by Bijoy Thomas 03 May '05

03 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Hi, Thanks, Bijoy Thomas. _______________________________________________ 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.… How are system calls implemented in Mac OS X? Are they implemented as software interrupts as in Linux? How does the argument passing from user space to kernel space take place? Any info/docs/links would be greatly appreciated. This email sent to site_archiver(a)lists.apple.com

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Re: tracing the mount syscall
by Bijoy Thomas 03 May '05

03 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Regards, Bijoy Thomas. On May 1, 2005, at 6:43 PM, Bijoy Thomas wrote: Hi, Thanks in advance, Bijoy Thomas. This email sent to bijoyjth(a)bluebottle.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.… Finally figured out what the problem was ... it seems the xxxfs_mount call was getting path variable that had nothing in it. This was causing copyinstr to fail resulting in the kernel panic .. and .. yeah .. the mount syscall just calls xxxfs_mount. I don't know why the path variable was empty. When i made the mount syscall, i had provided a path. I'm trying to write a new filesystem kext for the kernel. I just want to fill in the necessary vfsops to get the mount to succeed. After going through the mount source in vfs_syscalls.c, it seems that only the xxxfs_mount function is called. I wrote a dummy xxxfs_mount function to return 0, but my kernel panics when i run mount. I guess there is more to mount than just xxxfs_mount. I'm guessing that xxxfs_root and xxxfs_vget are called somewhere. Can anyone provide any info on what functions are called and when during a mount? _______________________________________________ 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/ bijoyjth%40bluebottle.com This email sent to site_archiver(a)lists.apple.com

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Re: IODelay function
by Dan Markarian 02 May '05

02 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Hi Imran, Dan On 2 May 2005, at 10:14 AM, Imran Kazi wrote: Hi folks, I had written media filter scheme driver. I have implemented read/write routine in the driver. I am able to successfully write on the disk using this driver. Thanks in advance. Imran _______________________________________________ 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.… IODelay() as a synchronization technique is a bit worrisome. Why not issue the read to your driver asynchronously, and once it completes and your callback is called, then issue the write, which is, of course, asynchronous to begin with? You can read a bit more about the concept of Completion Chaining in I/ O Kit Fundamentals. http://developer.apple.com/documentation/DeviceDrivers/Conceptual/ IOKitFundamentals/HandlingEvents/chapter_8_section_3.html#//apple_ref/ doc/uid/TP0000018-DontLinkElementID_180587 Actually i have to hold the write routine for a small time interval say (few seconds),so that i call the read routine of my driver and read the data on the disk and then call the write routine. I am doing this to read the data on the disk and copy it to some other disk before my original write routine modifies the data on the disk. I am using IODelay routine to delay my driver write routine for a few seconds. But because of IODelay function my read routine also gets delay as i am specifying IODelay before calling read routine. Is it possible to delay only write call and not the read call, so that I call my driver read routine to get the data on the disk and then call write routine??? This email sent to site_archiver(a)lists.apple.com

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Re: VNODE sample under Tiger
by Justin Walker 02 May '05

02 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On May 2, 2005, at 11:57, Pezeshgi, Shahriar wrote: Hi all Can someone help me with this question? Where can I find information regarding vnode_open, vnode_close and etc function in Tiger? They should be in kernel source code but I haven't find them, I need exact file or project name. Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large Institute for General Semantics -------- If you're not confused, You're not paying attention -------- _______________________________________________ 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.… cd to the top-level directory (xnu-xxx), and execute "make cscope". Then use cscope(1) (see the man page); it will help you find what you want. This email sent to site_archiver(a)lists.apple.com

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Re: blocking writes and tiger update
by Markus Hitter 02 May '05

02 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Am 02.05.2005 um 20:17 schrieb Nicolas Berloquin: What's wrong with mounting the thing read-only? Why are you mounting it at all? Markus (Not a driver expert) - - - - - - - - - - - - - - - - - - - Dipl. Ing. Markus Hitter http://www.jump-ing.de/ _______________________________________________ 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.… I've searched the archives about blocking writes (or other accesses) This email sent to site_archiver(a)lists.apple.com

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Re: blocking writes and tiger update
by Shawn Erickson 02 May '05

02 May '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On May 2, 2005, at 11:17 AM, Nicolas Berloquin wrote: Hello ! You seen the following (note the VFS section)...? -Shawn _______________________________________________ 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 I'm new to the list, but I saw a few familiar names posting here ;D I've searched the archives about blocking writes (or other accesses) on a storage device and found some suggestions like : 1 - use a stacked nullfs-like driver and call the 'super' methods. 2 - never use a stacked driver... ever 3 - the docs on vfs say that vfs are going to change, so don't use that. (even at todays' date, ie after tiger release.) Since the docs on developer.apple.com haven't been updated for tiger, I'm wondering what the current state of affair is about all that. Is is still verboten to use nullfs-like techniques ? Will apple implement an NKE type of API, FSKE with usable hooks ? thanks for any pointers or hints ^_^ <http://developer.apple.com/documentation/Darwin/Reference/ KPI_Reference/kpi_reference.html> Also on Apple ADC downloads (log into ADC account, may require a seed key) you can find a set of file system plugin samples. Anyway what exactly do mean by blocking writes? What are you trying to achieve? smime.p7s

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