per file lock list

From: Igor Shmukler (igor.shmukler_at_gmail.com)
Date: 07/21/05

  • Next message: Sam Pierson: "Re: Atheros, hardware access layer, collisions" 
    Date: Thu, 21 Jul 2005 15:10:30 -0400
To: fs@freebsd.org, hackers@freebsd.org, dillon@apollo.backplane.com

    Hi,

    We have a question: how to get all POSIX locks for a given file?

    As far as I know, existing API does not allow to retrieve all file
    locks. Therefore, we need to use kernel internal structures to get all
    applied locks. Unfortunately, a head of list with file locks is
    attached to inode rather then vnode. As result, it is much harder to
    get the lock list head due to the need to know exact inode type that
    is hidden behind the vnode.

    Of course, the problem could be resolved in a hackish way: we may get
    the address of VOP_ADVLOCK() method and compare it with all known FS
    methods, that handles this VOP operation: (ufs_advlock, etc.) and
    therefore apply a proper type cast to vnode->v_data to get valid
    inode. However, this would be a last resort.

    So the question: is there an elegant way to get the lock list for a given file?

    Thank you in advance.
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  • Next message: Sam Pierson: "Re: Atheros, hardware access layer, collisions"

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