diff options
| author | neal <neal> | 2007-12-12 17:49:55 +0000 |
|---|---|---|
| committer | neal <neal> | 2007-12-12 17:49:55 +0000 |
| commit | 8eb5ea7006b2d9f37ce753bb10e0a1efcd5e76d3 (patch) | |
| tree | 1d7cbb522638f6b3cabe0b1732f4da6b2d95ad8b /viengoos/as.c | |
| parent | 88e93a2eaca6b06556eb7438f91d8f4841c422f9 (diff) | |
2007-12-12 Neal H. Walfield <neal@gnu.org>
* as.c (as_build_internal): If the required capability slot is not
cap_void but MAY_OVERWRITE is true, return that slot.
Diffstat (limited to 'viengoos/as.c')
| -rw-r--r-- | viengoos/as.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/viengoos/as.c b/viengoos/as.c index d6b68f8..717b344 100644 --- a/viengoos/as.c +++ b/viengoos/as.c @@ -80,6 +80,7 @@ as_build_internal (activity_t activity, l4_uint64_t root_guard = CAP_GUARD (root); int root_gbits = CAP_GUARD_BITS (root); + if (root->type != cap_void && remaining >= root_gbits && root_guard == extract_bits64_inv (addr, @@ -87,14 +88,28 @@ as_build_internal (activity_t activity, /* ROOT's (possibly zero-width) guard matches and thus translates part of the address. */ { + if (remaining == root_gbits && may_overwrite) + { + debug (0, "Overwriting " ADDR_FMT " with " ADDR_FMT + " (at " ADDR_FMT ")", + ADDR_PRINTF (addr_extend (addr_chop (a, remaining), + root_guard, root_gbits)), + ADDR_PRINTF (a), + ADDR_PRINTF (addr_chop (a, remaining))); + /* XXX: Free any data associated with the capability + (e.g., shadow pages). */ + break; + } + /* Subtract the number of bits the guard translates. */ remaining -= root_gbits; assert (remaining >= 0); if (remaining == 0) /* ROOT is not a void capability yet the guard translates - all of the bits. This means that ROOT references an - object at ADDR. This is a problem: we want to insert a + all of the bits and we may not overwrite the + capability. This means that ROOT references an object + at ADDR. This is a problem: we want to insert a capability at ADDR. */ { AS_DUMP; |