)]}'
{
  "commit": "6328650bb4d854a7dc1498d1c0048b838b0d340c",
  "tree": "0e265dc86f7c4451647c1e227843cdd1530f9651",
  "parents": [
    "70d327198a434edb95b3d858bc8010b8add28e3e"
  ],
  "author": {
    "name": "Hugh Dickins",
    "email": "hughd@google.com",
    "time": "Wed Aug 03 16:21:18 2011 -0700"
  },
  "committer": {
    "name": "Linus Torvalds",
    "email": "torvalds@linux-foundation.org",
    "time": "Wed Aug 03 14:25:22 2011 -1000"
  },
  "message": "radix_tree: exceptional entries and indices\n\nA patchset to extend tmpfs to MAX_LFS_FILESIZE by abandoning its\npeculiar swap vector, instead keeping a file\u0027s swap entries in the same\nradix tree as its struct page pointers: thus saving memory, and\nsimplifying its code and locking.\n\nThis patch:\n\nThe radix_tree is used by several subsystems for different purposes.  A\nmajor use is to store the struct page pointers of a file\u0027s pagecache for\nmemory management.  But what if mm wanted to store something other than\npage pointers there too?\n\nThe low bit of a radix_tree entry is already used to denote an indirect\npointer, for internal use, and the unlikely radix_tree_deref_retry()\ncase.\n\nDefine the next bit as denoting an exceptional entry, and supply inline\nfunctions radix_tree_exception() to return non-0 in either unlikely\ncase, and radix_tree_exceptional_entry() to return non-0 in the second\ncase.\n\nIf a subsystem already uses radix_tree with that bit set, no problem: it\ndoes not affect internal workings at all, but is defined for the\nconvenience of those storing well-aligned pointers in the radix_tree.\n\nThe radix_tree_gang_lookups have an implicit assumption that the caller\ncan deduce the offset of each entry returned e.g.  by the page-\u003eindex of\na struct page.  But that may not be feasible for some kinds of item to\nbe stored there.\n\nradix_tree_gang_lookup_slot() allow for an optional indices argument,\noutput array in which to return those offsets.  The same could be added\nto other radix_tree_gang_lookups, but for now keep it to the only one\nfor which we need it.\n\nSigned-off-by: Hugh Dickins \u003chughd@google.com\u003e\nAcked-by: Rik van Riel \u003criel@redhat.com\u003e\nSigned-off-by: Andrew Morton \u003cakpm@linux-foundation.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@linux-foundation.org\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "23241c2feccee7b542ac1e984c91b13a02be0541",
      "old_mode": 33188,
      "old_path": "include/linux/radix-tree.h",
      "new_id": "b7edf8251455153de9bdeb19be3fa9bd50753765",
      "new_mode": 33188,
      "new_path": "include/linux/radix-tree.h"
    },
    {
      "type": "modify",
      "old_id": "7ea2e033d7153ad23de9dc02c0c0786abc1e11e2",
      "old_mode": 33188,
      "old_path": "lib/radix-tree.c",
      "new_id": "348eaefbed74c38b7cc2554f4a7a111280f65f2e",
      "new_mode": 33188,
      "new_path": "lib/radix-tree.c"
    },
    {
      "type": "modify",
      "old_id": "867d40222ec798ce99a8332b991e8d7c4bdfb8ec",
      "old_mode": 33188,
      "old_path": "mm/filemap.c",
      "new_id": "b83aebfd0a00e688e54cbc71abc644870942a902",
      "new_mode": 33188,
      "new_path": "mm/filemap.c"
    }
  ]
}