1a63143dc1
A programmer who is trying to implement calling the btrfs SEARCH or SEARCH_V2 ioctl will probably soon end up reading this struct definition. Properly document the input fields to prevent common misconceptions: 1. The search space is linear, not 3 dimensional. The invidual min/max values for objectid, type and offset cannot be used to filter the result, they only define the endpoints of an interval. 2. The transaction id (a.k.a. generation) filter applies only on transaction id of the last COW operation on a whole metadata page, not on individual items. Ad 1. The first misunderstanding was helped by the previous misleading comments on min/max type and offset: "keys returned will be >= min and <= max". Ad 2. For example, running btrfs balance will happily cause rewriting of metadata pages that contain a filesystem tree of a read only subvolume, causing transids to be increased. Also, improve descriptions of tree_id and nr_items and add in/out annotations. Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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| drivers | ||
| firmware | ||
| fs | ||
| include | ||
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| ipc | ||
| kernel | ||
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| samples | ||
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| .cocciconfig | ||
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| README | ||
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.