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21b6ad2124
This is to document operations and to also list their in/out arguments. This list was auto generated and only partly verified, use with care. Not all operations are supported by libfuse yet. |
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| .. | ||
| .gitignore | ||
| Doxyfile | ||
| fast17-vangoor.pdf | ||
| fusermount3.1 | ||
| kernel.txt | ||
| libfuse-operations.txt | ||
| mainpage.dox | ||
| meson.build | ||
| mount.fuse3.8 | ||
| README.NFS | ||
NFS exporting is supported in Linux kernels 2.6.27 or later. You need to add an fsid=NNN option to /etc/exports to make exporting a FUSE directory work. Filesystem support ------------------ NFS exporting works to some extent on all fuse filesystems, but not perfectly. This is due to the stateless nature of the protocol, the server has no way of knowing whether the client is keeping a reference to a file or not, and hence that file may be removed from the server's cache. In that case there has to be a way to look up that object using the inode number, otherwise an ESTALE error will be returned. 1) low-level interface Filesystems need to set FUSE_CAP_EXPORT_SUPPORT in conn->wants and implement special lookups for the names "." and "..". The former may be requested on any inode, including non-directories, while the latter is only requested for directories. Otherwise these special lookups should behave identically to ordinary lookups. Furthermore, setting FUSE_CAP_EXPORT_SUPPORT requires the file system to handle node-ids (fuse_ino_t) that the file system may does not know about - e.g. a fuse FORGET request might have been received or the node-id was used in a previous instance of the file system daemon. The node-id might not be valid at all when an invalid handle is passed to open_by_handle_at(). This implies that the filesystem *must not* reuse node-ids even if generation numbers are set correctly. This is because generation numbers are not provided by the kernel to e.g. the getattr() handler, so the handler would be unable to tell if the provided node-id refers to the "known" current one, or a previous one that has been forgotten and re-used. 2) high-level interface Because the high-level interface is path based, it is not possible to delegate looking up by inode to the filesystem. To work around this, currently a "noforget" option is provided, which makes the library remember nodes forever. This will make the NFS server happy, but also results in an ever growing memory footprint for the filesystem. For this reason if the filesystem is large (or the memory is small), then this option is not recommended.