--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+#ifndef CEPH_MDS_FLOCK_H
+#define CEPH_MDS_FLOCK_H
+
+#include <errno.h>
+
+#include "common/debug.h"
+#include "mdstypes.h"
+
+
+inline ostream& operator<<(ostream& out, const ceph_filelock& l) {
+ out << "start: " << l.start << ", length: " << l.length
+ << ", client: " << l.client << ", owner: " << l.owner
+ << ", pid: " << l.pid << ", type: " << (int)l.type
+ << std::endl;
+ return out;
+}
+
+inline bool ceph_filelock_owner_equal(const ceph_filelock& l, const ceph_filelock& r)
+{
+ if (l.client != r.client || l.owner != r.owner)
+ return false;
+ // The file lock is from old client if the most significant bit of
+ // 'owner' is not set. Old clients use both 'owner' and 'pid' to
+ // identify the owner of lock.
+ if (l.owner & (1ULL << 63))
+ return true;
+ return l.pid == r.pid;
+}
+
+inline int ceph_filelock_owner_compare(const ceph_filelock& l, const ceph_filelock& r)
+{
+ if (l.client != r.client)
+ return l.client > r.client ? 1 : -1;
+ if (l.owner != r.owner)
+ return l.owner > r.owner ? 1 : -1;
+ if (l.owner & (1ULL << 63))
+ return 0;
+ if (l.pid != r.pid)
+ return l.pid > r.pid ? 1 : -1;
+ return 0;
+}
+
+inline int ceph_filelock_compare(const ceph_filelock& l, const ceph_filelock& r)
+{
+ int ret = ceph_filelock_owner_compare(l, r);
+ if (ret)
+ return ret;
+ if (l.start != r.start)
+ return l.start > r.start ? 1 : -1;
+ if (l.length != r.length)
+ return l.length > r.length ? 1 : -1;
+ if (l.type != r.type)
+ return l.type > r.type ? 1 : -1;
+ return 0;
+}
+
+inline bool operator<(const ceph_filelock& l, const ceph_filelock& r)
+{
+ return ceph_filelock_compare(l, r) < 0;
+}
+
+inline bool operator==(const ceph_filelock& l, const ceph_filelock& r) {
+ return ceph_filelock_compare(l, r) == 0;
+}
+
+inline bool operator!=(const ceph_filelock& l, const ceph_filelock& r) {
+ return ceph_filelock_compare(l, r) != 0;
+}
+
+class ceph_lock_state_t {
+ CephContext *cct;
+ int type;
+public:
+ explicit ceph_lock_state_t(CephContext *cct_, int type_) : cct(cct_), type(type_) {}
+ ~ceph_lock_state_t();
+ multimap<uint64_t, ceph_filelock> held_locks; // current locks
+ multimap<uint64_t, ceph_filelock> waiting_locks; // locks waiting for other locks
+ // both of the above are keyed by starting offset
+ map<client_t, int> client_held_lock_counts;
+ map<client_t, int> client_waiting_lock_counts;
+
+ /**
+ * Check if a lock is on the waiting_locks list.
+ *
+ * @param fl The filelock to check for
+ * @returns True if the lock is waiting, false otherwise
+ */
+ bool is_waiting(const ceph_filelock &fl) const;
+ /**
+ * Remove a lock from the waiting_locks list
+ *
+ * @param fl The filelock to remove
+ */
+ void remove_waiting(const ceph_filelock& fl);
+ /*
+ * Try to set a new lock. If it's blocked and wait_on_fail is true,
+ * add the lock to waiting_locks.
+ * The lock needs to be of type CEPH_LOCK_EXCL or CEPH_LOCK_SHARED.
+ * This may merge previous locks, or convert the type of already-owned
+ * locks.
+ *
+ * @param new_lock The lock to set
+ * @param wait_on_fail whether to wait until the lock can be set.
+ * Otherwise it fails immediately when blocked.
+ *
+ * @returns true if set, false if not set.
+ */
+ bool add_lock(ceph_filelock& new_lock, bool wait_on_fail, bool replay,
+ bool *deadlock);
+ /**
+ * See if a lock is blocked by existing locks. If the lock is blocked,
+ * it will be set to the value of the first blocking lock. Otherwise,
+ * it will be returned unchanged, except for setting the type field
+ * to CEPH_LOCK_UNLOCK.
+ *
+ * @param testing_lock The lock to check for conflicts on.
+ */
+ void look_for_lock(ceph_filelock& testing_lock);
+
+ /*
+ * Remove lock(s) described in old_lock. This may involve splitting a
+ * previous lock or making a previous lock smaller.
+ *
+ * @param removal_lock The lock to remove
+ * @param activated_locks A return parameter, holding activated wait locks.
+ */
+ void remove_lock(const ceph_filelock removal_lock,
+ list<ceph_filelock>& activated_locks);
+
+ bool remove_all_from(client_t client);
+private:
+ static const unsigned MAX_DEADLK_DEPTH = 5;
+
+ /**
+ * Check if adding the lock causes deadlock
+ *
+ * @param fl The blocking filelock
+ * @param overlapping_locks list of all overlapping locks
+ * @param first_fl
+ * @depth recursion call depth
+ */
+ bool is_deadlock(const ceph_filelock& fl,
+ list<multimap<uint64_t, ceph_filelock>::iterator>&
+ overlapping_locks,
+ const ceph_filelock *first_fl=NULL, unsigned depth=0) const;
+
+ /**
+ * Add a lock to the waiting_locks list
+ *
+ * @param fl The filelock to add
+ */
+ void add_waiting(const ceph_filelock& fl);
+
+ /**
+ * Adjust old locks owned by a single process so that process can set
+ * a new lock of different type. Handle any changes needed to the old locks
+ * (and the new lock) so that once the new lock is inserted into the
+ * held_locks list the process has a coherent, non-fragmented set of lock
+ * ranges. Make sure any overlapping locks are combined, trimmed, and removed
+ * as needed.
+ * This function should only be called once you know the lock will be
+ * inserted, as it DOES adjust new_lock. You can call this function
+ * on an empty list, in which case it does nothing.
+ * This function does not remove elements from old_locks, so regard the list
+ * as bad information following function invocation.
+ *
+ * @param new_lock The new lock the process has requested.
+ * @param old_locks list of all locks currently held by same
+ * client/process that overlap new_lock.
+ * @param neighbor_locks locks owned by same process that neighbor new_lock on
+ * left or right side.
+ */
+ void adjust_locks(list<multimap<uint64_t, ceph_filelock>::iterator> old_locks,
+ ceph_filelock& new_lock,
+ list<multimap<uint64_t, ceph_filelock>::iterator>
+ neighbor_locks);
+
+ //get last lock prior to start position
+ multimap<uint64_t, ceph_filelock>::iterator
+ get_lower_bound(uint64_t start,
+ multimap<uint64_t, ceph_filelock>& lock_map);
+ //get latest-starting lock that goes over the byte "end"
+ multimap<uint64_t, ceph_filelock>::iterator
+ get_last_before(uint64_t end,
+ multimap<uint64_t, ceph_filelock>& lock_map);
+
+ /*
+ * See if an iterator's lock covers any of the same bounds as a given range
+ * Rules: locks cover "length" bytes from "start", so the last covered
+ * byte is at start + length - 1.
+ * If the length is 0, the lock covers from "start" to the end of the file.
+ */
+ bool share_space(multimap<uint64_t, ceph_filelock>::iterator& iter,
+ uint64_t start, uint64_t end);
+
+ bool share_space(multimap<uint64_t, ceph_filelock>::iterator& iter,
+ const ceph_filelock &lock) {
+ uint64_t end = lock.start;
+ if (lock.length) {
+ end += lock.length - 1;
+ } else { // zero length means end of file
+ end = uint64_t(-1);
+ }
+ return share_space(iter, lock.start, end);
+ }
+ /*
+ *get a list of all locks overlapping with the given lock's range
+ * lock: the lock to compare with.
+ * overlaps: an empty list, to be filled.
+ * Returns: true if at least one lock overlaps.
+ */
+ bool get_overlapping_locks(const ceph_filelock& lock,
+ list<multimap<uint64_t,
+ ceph_filelock>::iterator> & overlaps,
+ list<multimap<uint64_t,
+ ceph_filelock>::iterator> *self_neighbors);
+
+
+ bool get_overlapping_locks(const ceph_filelock& lock,
+ list<multimap<uint64_t, ceph_filelock>::iterator>& overlaps) {
+ return get_overlapping_locks(lock, overlaps, NULL);
+ }
+
+ /**
+ * Get a list of all waiting locks that overlap with the given lock's range.
+ * lock: specifies the range to compare with
+ * overlaps: an empty list, to be filled
+ * Returns: true if at least one waiting_lock overlaps
+ */
+ bool get_waiting_overlaps(const ceph_filelock& lock,
+ list<multimap<uint64_t,
+ ceph_filelock>::iterator>& overlaps);
+ /*
+ * split a list of locks up by whether they're owned by same
+ * process as given lock
+ * owner: the owning lock
+ * locks: the list of locks (obtained from get_overlapping_locks, probably)
+ * Will have all locks owned by owner removed
+ * owned_locks: an empty list, to be filled with the locks owned by owner
+ */
+ void split_by_owner(const ceph_filelock& owner,
+ list<multimap<uint64_t,
+ ceph_filelock>::iterator> & locks,
+ list<multimap<uint64_t,
+ ceph_filelock>::iterator> & owned_locks);
+
+ ceph_filelock *contains_exclusive_lock(list<multimap<uint64_t,
+ ceph_filelock>::iterator>& locks);
+
+public:
+ void encode(bufferlist& bl) const {
+ ::encode(held_locks, bl);
+ ::encode(client_held_lock_counts, bl);
+ }
+ void decode(bufferlist::iterator& bl) {
+ ::decode(held_locks, bl);
+ ::decode(client_held_lock_counts, bl);
+ }
+ bool empty() const {
+ return held_locks.empty() && waiting_locks.empty() &&
+ client_held_lock_counts.empty() &&
+ client_waiting_lock_counts.empty();
+ }
+};
+WRITE_CLASS_ENCODER(ceph_lock_state_t)
+
+
+inline ostream& operator<<(ostream &out, const ceph_lock_state_t &l) {
+ out << "ceph_lock_state_t. held_locks.size()=" << l.held_locks.size()
+ << ", waiting_locks.size()=" << l.waiting_locks.size()
+ << ", client_held_lock_counts -- " << l.client_held_lock_counts
+ << "\n client_waiting_lock_counts -- " << l.client_waiting_lock_counts
+ << "\n held_locks -- ";
+ for (auto iter = l.held_locks.begin();
+ iter != l.held_locks.end();
+ ++iter)
+ out << iter->second;
+ out << "\n waiting_locks -- ";
+ for (auto iter =l.waiting_locks.begin();
+ iter != l.waiting_locks.end();
+ ++iter)
+ out << iter->second << "\n";
+ return out;
+}
+
+#endif
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