os/FuseStore: use offset for readdir

This allows us to list large directories.

Signed-off-by: Sage Weil <sage@redhat.com>

diff --git a/src/os/FuseStore.cc b/src/os/FuseStore.cc
index 37a22af11510c8dbb731a94e9f48f4ff60815bd5..5d8303b7372a9ff65d02709debd8585fca60857a 100644 (file)
--- a/src/os/FuseStore.cc
+++ b/src/os/FuseStore.cc
@@ -359,6 +359,9 @@ static int os_readdir(const char *path,
   fuse_context *fc = fuse_get_context();
   FuseStore *fs = static_cast<FuseStore*>(fc->private_data);
 
+  // we can't shift 32 bits or else off_t will go negative
+  const int hash_shift = 31;
+
   switch (t) {
   case FN_ROOT:
     {
@@ -400,38 +403,36 @@ static int os_readdir(const char *path,
     }
     break;
 
-  case FN_ALL:
-    {
-      ghobject_t next;
-      while (true) {
-       vector<ghobject_t> ls;
-       int r = fs->store->collection_list(
-         cid, next, ghobject_t::get_max(), true, 1000, &ls, &next);
-       if (r < 0)
-         break;
-       for (auto p : ls) {
-         string s = stringify(p);
-         filler(buf, s.c_str(), NULL, 0);
-       }
-       if (next == ghobject_t::get_max())
-         break;
-      }
-    }
-    break;
-
   case FN_HASH_VAL:
+  case FN_ALL:
     {
+      uint32_t bitwise_hash = (offset >> hash_shift) & 0xffffffff;
+      uint32_t hashoff = offset - (bitwise_hash << hash_shift);
+      int skip = hashoff;
       ghobject_t next = cid.get_min_hobj();
-      next.hobj.set_hash(hobject_t::_reverse_bits(hash_value));
-      ghobject_t last = next;
-      uint64_t rev_end = (hash_value | (0xffffffff >> hash_bits)) + 1;
-      if (rev_end >= 0x100000000)
+      if (offset) {
+       // obey the offset
+       next.hobj.set_hash(hobject_t::_reverse_bits(bitwise_hash));
+      } else if (t == FN_HASH_VAL) {
+       next.hobj.set_hash(hobject_t::_reverse_bits(hash_value));
+      }
+      ghobject_t last;
+      if (t == FN_HASH_VAL) {
+       last = next;
+       uint64_t rev_end = (hash_value | (0xffffffff >> hash_bits)) + 1;
+       if (rev_end >= 0x100000000)
+         last = ghobject_t::get_max();
+       else
+         last.hobj.set_hash(hobject_t::_reverse_bits(rev_end));
+      } else {
        last = ghobject_t::get_max();
-      else
-       last.hobj.set_hash(hobject_t::_reverse_bits(rev_end));
-      dout(10) << __func__ << " hash " << std::hex
-              << hobject_t::_reverse_bits(hash_value) << std::dec
-              << "/" << hash_bits << " first " << next << " last " << last
+      }
+      dout(10) << __func__ << std::hex
+              << " offset " << offset << " hash "
+              << hobject_t::_reverse_bits(hash_value)
+              << std::dec
+              << "/" << hash_bits
+              << " first " << next << " last " << last
               << dendl;
       while (true) {
        vector<ghobject_t> ls;
@@ -440,9 +441,25 @@ static int os_readdir(const char *path,
        if (r < 0)
          break;
        for (auto p : ls) {
+         if (skip) {
+           --skip;
+           continue;
+         }
+         uint32_t cur_bitwise_hash = p.hobj.get_bitwise_key_u32();
+         if (cur_bitwise_hash != bitwise_hash) {
+           bitwise_hash = cur_bitwise_hash;
+           hashoff = 0;
+         }
+         ++hashoff;
+         uint64_t cur_off = ((uint64_t)bitwise_hash << hash_shift) |
+           (uint64_t)hashoff;
          string s = stringify(p);
-         filler(buf, s.c_str(), NULL, 0);
+         r = filler(buf, s.c_str(), NULL, cur_off);
+         if (r)
+           break;
        }
+       if (r)
+         break;
        if (next == ghobject_t::get_max() || next == last)
          break;
       }