LU-6179 llite: Implement ladvise lockahead

[fs/lustre-release.git] / lustre / include / cl_object.h

diff --git a/lustre/include/cl_object.h b/lustre/include/cl_object.h
index 78d0926..00bd414 100644 (file)
--- a/lustre/include/cl_object.h
+++ b/lustre/include/cl_object.h
@@ -1607,25 +1607,30 @@ enum cl_enq_flags {
          * -EWOULDBLOCK is returned immediately.
          */
         CEF_NONBLOCK     = 0x00000001,
-        /**
-         * take lock asynchronously (out of order), as it cannot
-         * deadlock. This is for LDLM_FL_HAS_INTENT locks used for glimpsing.
-         */
-        CEF_ASYNC        = 0x00000002,
+       /**
+        * Tell lower layers this is a glimpse request, translated to
+        * LDLM_FL_HAS_INTENT at LDLM layer.
+        *
+        * Also, because glimpse locks never block other locks, we count this
+        * as automatically compatible with other osc locks.
+        * (see osc_lock_compatible)
+        */
+       CEF_GLIMPSE        = 0x00000002,
         /**
          * tell the server to instruct (though a flag in the blocking ast) an
          * owner of the conflicting lock, that it can drop dirty pages
          * protected by this lock, without sending them to the server.
          */
         CEF_DISCARD_DATA = 0x00000004,
-        /**
-         * tell the sub layers that it must be a `real' lock. This is used for
-         * mmapped-buffer locks and glimpse locks that must be never converted
-         * into lockless mode.
-         *
-         * \see vvp_mmap_locks(), cl_glimpse_lock().
-         */
-        CEF_MUST         = 0x00000008,
+       /**
+        * tell the sub layers that it must be a `real' lock. This is used for
+        * mmapped-buffer locks, glimpse locks, manually requested locks
+        * (LU_LADVISE_LOCKAHEAD) that must never be converted into lockless
+        * mode.
+        *
+        * \see vvp_mmap_locks(), cl_glimpse_lock, cl_request_lock().
+        */
+       CEF_MUST         = 0x00000008,
         /**
          * tell the sub layers that never request a `real' lock. This flag is
          * not used currently.
@@ -1638,9 +1643,16 @@ enum cl_enq_flags {
          */
         CEF_NEVER        = 0x00000010,
         /**
-         * for async glimpse lock.
+        * tell the dlm layer this is a speculative lock request
+        * speculative lock requests are locks which are not requested as part
+        * of an I/O operation.  Instead, they are requested because we expect
+        * to use them in the future.  They are requested asynchronously at the
+        * ptlrpc layer.
+        *
+        * Currently used for asynchronous glimpse locks and manually requested
+        * locks (LU_LADVISE_LOCKAHEAD).
          */
-        CEF_AGL          = 0x00000020,
+       CEF_SPECULATIVE          = 0x00000020,
        /**
         * enqueue a lock to test DLM lock existence.
         */
@@ -1651,9 +1663,13 @@ enum cl_enq_flags {
         */
        CEF_LOCK_MATCH  = 0x00000080,
        /**
+        * tell the DLM layer to lock only the requested range
+        */
+       CEF_LOCK_NO_EXPAND    = 0x00000100,
+       /**
         * mask of enq_flags.
         */
-       CEF_MASK         = 0x000000ff,
+       CEF_MASK         = 0x000001ff,
 };
 
 /**
@@ -1871,7 +1887,9 @@ struct cl_io {
         */
                             ci_noatime:1,
        /** Set to 1 if parallel execution is allowed for current I/O? */
-                            ci_pio:1;
+                            ci_pio:1,
+       /* Tell sublayers not to expand LDLM locks requested for this IO */
+                            ci_lock_no_expand:1;
        /**
         * Number of pages owned by this IO. For invariant checking.
         */