Nfs readdir

From Linux NFS

nfs_readdir()

• fs/nfs/dir.c
• dentry defined in include/linux/dcache.h
• file defined in include/linux/fs.h
• path defined in include/linux/path.h
• nfs_entry defined in /include/linux/nfs_xdr.h

• make a new dentry: my_entry
  • set the cookie to the previous file, allocate a file handle and attribute struct, mark that we are not at the end of the file
  • If allocations failed, goto out_alloc_failed to free memory and print a warning

• call nfs_revalidate_mapping (fs/nfs/inode.c) to validate the page cache
  • if there is an error revalidating the cache, goto out to allow silly renames and free fattr / filehandle structs

• Begin a loop over directory entries

• while we have not reached the end of the directory file:
  • Search the page cache for the requested page (dir.c: readdir_search_pagecache)
  • if searching results in a bad cookie, it could mean that we are at the end of the directory or that the file has been deleted
    • ask the server fore the next file and add to the page cache using filldir (dir.c: uncached_readdir)
    • if the response is good, go to the beginning of the while loop and look up the next entry, otherwise break out of the loop and return