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LU-3027 lov: to not modify lov lock when sublock is canceled
[fs/lustre-release.git] / lustre / lov / lov_lock.c
index 563b625..547bdca 100644 (file)
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  * GPL HEADER END
  */
 /*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2013, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -147,7 +147,7 @@ static struct cl_lock *lov_sublock_alloc(const struct lu_env *env,
         LASSERT(idx < lck->lls_nr);
         ENTRY;
 
-        OBD_SLAB_ALLOC_PTR_GFP(link, lov_lock_link_kmem, CFS_ALLOC_IO);
+       OBD_SLAB_ALLOC_PTR_GFP(link, lov_lock_link_kmem, __GFP_IO);
         if (link != NULL) {
                 struct lov_sublock_env *subenv;
                 struct lov_lock_sub  *lls;
@@ -155,7 +155,7 @@ static struct cl_lock *lov_sublock_alloc(const struct lu_env *env,
 
                 parent = lck->lls_cl.cls_lock;
                 lls    = &lck->lls_sub[idx];
-                descr  = &lls->sub_descr;
+                descr  = &lls->sub_got;
 
                 subenv = lov_sublock_env_get(env, parent, lls);
                 if (!IS_ERR(subenv)) {
@@ -267,12 +267,14 @@ static int lov_subresult(int result, int rc)
         int result_rank;
         int rc_rank;
 
-        LASSERT(result <= 0 || result == CLO_REPEAT || result == CLO_WAIT);
-        LASSERT(rc <= 0 || rc == CLO_REPEAT || rc == CLO_WAIT);
-        CLASSERT(CLO_WAIT < CLO_REPEAT);
-
         ENTRY;
 
+       LASSERTF(result <= 0 || result == CLO_REPEAT || result == CLO_WAIT,
+                "result = %d", result);
+       LASSERTF(rc <= 0 || rc == CLO_REPEAT || rc == CLO_WAIT,
+                "rc = %d\n", rc);
+        CLASSERT(CLO_WAIT < CLO_REPEAT);
+
         /* calculate ranks in the ordering above */
         result_rank = result < 0 ? 1 + CLO_REPEAT : result;
         rc_rank = rc < 0 ? 1 + CLO_REPEAT : rc;
@@ -316,12 +318,12 @@ static int lov_lock_sub_init(const struct lu_env *env,
                  * XXX for wide striping smarter algorithm is desirable,
                  * breaking out of the loop, early.
                  */
-                if (lov_stripe_intersects(r0->lo_lsm, i,
+               if (lov_stripe_intersects(loo->lo_lsm, i,
                                           file_start, file_end, &start, &end))
                         nr++;
         }
         LASSERT(nr > 0);
-        OBD_ALLOC(lck->lls_sub, nr * sizeof lck->lls_sub[0]);
+        OBD_ALLOC_LARGE(lck->lls_sub, nr * sizeof lck->lls_sub[0]);
         if (lck->lls_sub == NULL)
                 RETURN(-ENOMEM);
 
@@ -334,7 +336,7 @@ static int lov_lock_sub_init(const struct lu_env *env,
          * top-lock.
          */
         for (i = 0, nr = 0; i < r0->lo_nr; ++i) {
-                if (lov_stripe_intersects(r0->lo_lsm, i,
+               if (lov_stripe_intersects(loo->lo_lsm, i,
                                           file_start, file_end, &start, &end)) {
                         struct cl_lock_descr *descr;
 
@@ -485,56 +487,27 @@ static void lov_lock_fini(const struct lu_env *env,
                          * a reference on its parent.
                          */
                         LASSERT(lck->lls_sub[i].sub_lock == NULL);
-                OBD_FREE(lck->lls_sub, lck->lls_nr * sizeof lck->lls_sub[0]);
+                OBD_FREE_LARGE(lck->lls_sub,
+                               lck->lls_nr * sizeof lck->lls_sub[0]);
         }
         OBD_SLAB_FREE_PTR(lck, lov_lock_kmem);
         EXIT;
 }
 
-/**
- *
- * \retval 0 if state-transition can proceed
- * \retval -ve otherwise.
- */
 static int lov_lock_enqueue_wait(const struct lu_env *env,
                                  struct lov_lock *lck,
                                  struct cl_lock *sublock)
 {
-        struct cl_lock *lock     = lck->lls_cl.cls_lock;
-        struct cl_lock *conflict = sublock->cll_conflict;
-        int result = CLO_REPEAT;
+        struct cl_lock *lock = lck->lls_cl.cls_lock;
+        int             result;
         ENTRY;
 
         LASSERT(cl_lock_is_mutexed(lock));
-        LASSERT(cl_lock_is_mutexed(sublock));
-        LASSERT(sublock->cll_state == CLS_QUEUING);
-        LASSERT(conflict != NULL);
 
-        sublock->cll_conflict = NULL;
         cl_lock_mutex_put(env, lock);
-        cl_lock_mutex_put(env, sublock);
-
-        LASSERT(cl_lock_nr_mutexed(env) == 0);
-
-        cl_lock_mutex_get(env, conflict);
-        cl_lock_cancel(env, conflict);
-        cl_lock_delete(env, conflict);
-        while (conflict->cll_state != CLS_FREEING) {
-                int rc = 0;
-
-                rc = cl_lock_state_wait(env, conflict);
-                if (rc == 0)
-                        continue;
-
-                result = lov_subresult(result, rc);
-                break;
-        }
-        cl_lock_mutex_put(env, conflict);
-        lu_ref_del(&conflict->cll_reference, "cancel-wait", sublock);
-        cl_lock_put(env, conflict);
-
+        result = cl_lock_enqueue_wait(env, sublock, 0);
         cl_lock_mutex_get(env, lock);
-        RETURN(result);
+        RETURN(result ?: CLO_REPEAT);
 }
 
 /**
@@ -553,17 +526,20 @@ static int lov_lock_enqueue_one(const struct lu_env *env, struct lov_lock *lck,
 
         /* first, try to enqueue a sub-lock ... */
         result = cl_enqueue_try(env, sublock, io, enqflags);
-        if (sublock->cll_state == CLS_ENQUEUED)
-                /* if it is enqueued, try to `wait' on it---maybe it's already
-                 * granted */
-                result = cl_wait_try(env, sublock);
+       if ((sublock->cll_state == CLS_ENQUEUED) && !(enqflags & CEF_AGL)) {
+               /* if it is enqueued, try to `wait' on it---maybe it's already
+                * granted */
+               result = cl_wait_try(env, sublock);
+               if (result == CLO_REENQUEUED)
+                       result = CLO_WAIT;
+       }
         /*
          * If CEF_ASYNC flag is set, then all sub-locks can be enqueued in
          * parallel, otherwise---enqueue has to wait until sub-lock is granted
          * before proceeding to the next one.
          */
-        if (result == CLO_WAIT && sublock->cll_state <= CLS_HELD &&
-            enqflags & CEF_ASYNC && !last)
+        if ((result == CLO_WAIT) && (sublock->cll_state <= CLS_HELD) &&
+            (enqflags & CEF_ASYNC) && (!last || (enqflags & CEF_AGL)))
                 result = 0;
         RETURN(result);
 }
@@ -676,8 +652,19 @@ static int lov_lock_enqueue(const struct lu_env *env,
                                                                    sublock);
                                         break;
                                 case CLS_CACHED:
+                                       cl_lock_get(sublock);
+                                        /* take recursive mutex of sublock */
+                                        cl_lock_mutex_get(env, sublock);
+                                       /* need to release all locks in closure
+                                        * otherwise it may deadlock. LU-2683.*/
+                                        lov_sublock_unlock(env, sub, closure,
+                                                           subenv);
+                                       /* sublock and parent are held. */
                                         rc = lov_sublock_release(env, lck, i,
                                                                  1, rc);
+                                       cl_lock_mutex_put(env, sublock);
+                                       cl_lock_put(env, sublock);
+                                       break;
                                 default:
                                         lov_sublock_unlock(env, sub, closure,
                                                            subenv);
@@ -726,7 +713,8 @@ static int lov_lock_unuse(const struct lu_env *env,
                 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
                 if (rc == 0) {
                         if (lls->sub_flags & LSF_HELD) {
-                                LASSERT(sublock->cll_state == CLS_HELD);
+                                LASSERT(sublock->cll_state == CLS_HELD ||
+                                        sublock->cll_state == CLS_ENQUEUED);
                                 rc = cl_unuse_try(subenv->lse_env, sublock);
                                 rc = lov_sublock_release(env, lck, i, 0, rc);
                         }
@@ -779,17 +767,9 @@ static void lov_lock_cancel(const struct lu_env *env,
 
                         switch(sublock->cll_state) {
                         case CLS_HELD:
-                                rc = cl_unuse_try(subenv->lse_env,
-                                                  sublock);
+                               rc = cl_unuse_try(subenv->lse_env, sublock);
                                 lov_sublock_release(env, lck, i, 0, 0);
                                 break;
-                        case CLS_ENQUEUED:
-                                /* TODO: it's not a good idea to cancel this
-                                 * lock because it's innocent. But it's
-                                 * acceptable. The better way would be to
-                                 * define a new lock method to unhold the
-                                 * dlm lock. */
-                                cl_lock_cancel(env, sublock);
                         default:
                                 lov_sublock_release(env, lck, i, 1, 0);
                                 break;
@@ -818,12 +798,15 @@ static int lov_lock_wait(const struct lu_env *env,
         struct lov_lock        *lck     = cl2lov_lock(slice);
         struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
         enum cl_lock_state      minstate;
+        int                     reenqueued;
         int                     result;
         int                     i;
 
         ENTRY;
 
-        for (result = 0, minstate = CLS_FREEING, i = 0; i < lck->lls_nr; ++i) {
+again:
+        for (result = 0, minstate = CLS_FREEING, i = 0, reenqueued = 0;
+             i < lck->lls_nr; ++i) {
                 int rc;
                 struct lovsub_lock     *sub;
                 struct cl_lock         *sublock;
@@ -843,10 +826,18 @@ static int lov_lock_wait(const struct lu_env *env,
                         minstate = min(minstate, sublock->cll_state);
                         lov_sublock_unlock(env, sub, closure, subenv);
                 }
+                if (rc == CLO_REENQUEUED) {
+                        reenqueued++;
+                        rc = 0;
+                }
                 result = lov_subresult(result, rc);
                 if (result != 0)
                         break;
         }
+        /* Each sublock only can be reenqueued once, so will not loop for
+         * ever. */
+        if (result == 0 && reenqueued != 0)
+                goto again;
         cl_lock_closure_fini(closure);
         RETURN(result ?: minstate >= CLS_HELD ? 0 : CLO_WAIT);
 }
@@ -892,6 +883,11 @@ static int lov_lock_use(const struct lu_env *env,
                                 if (rc != 0)
                                         rc = lov_sublock_release(env, lck,
                                                                  i, 1, rc);
+                        } else if (sublock->cll_state == CLS_NEW) {
+                                /* Sub-lock might have been canceled, while
+                                 * top-lock was cached. */
+                                result = -ESTALE;
+                                lov_sublock_release(env, lck, i, 1, result);
                         }
                         lov_sublock_unlock(env, sub, closure, subenv);
                 }
@@ -939,7 +935,7 @@ static int lock_lock_multi_match()
                 if (sub->sub_lock == NULL)
                         continue;
                 subobj = sub->sub_descr.cld_obj;
-                if (!lov_stripe_intersects(r0->lo_lsm, sub->sub_stripe,
+               if (!lov_stripe_intersects(loo->lo_lsm, sub->sub_stripe,
                                            fstart, fend, &start, &end))
                         continue;
                 subneed->cld_start = cl_index(subobj, start);
@@ -963,7 +959,7 @@ static int lov_lock_stripe_is_matching(const struct lu_env *env,
                                        const struct cl_lock_descr *child,
                                        const struct cl_lock_descr *descr)
 {
-        struct lov_stripe_md *lsm = lov_r0(lov)->lo_lsm;
+       struct lov_stripe_md *lsm = lov->lo_lsm;
         obd_off start;
         obd_off end;
         int result;
@@ -1022,6 +1018,14 @@ static int lov_lock_fits_into(const struct lu_env *env,
 
         ENTRY;
 
+       /* for top lock, it's necessary to match enq flags otherwise it will
+        * run into problem if a sublock is missing and reenqueue. */
+       if (need->cld_enq_flags != lov->lls_orig.cld_enq_flags)
+               return 0;
+
+       if (lov->lls_ever_canceled)
+               return 0;
+
         if (need->cld_mode == CLM_GROUP)
                 /*
                  * always allow to match group lock.
@@ -1033,7 +1037,7 @@ static int lov_lock_fits_into(const struct lu_env *env,
                                                      cl2lov(slice->cls_obj),
                                                      lov->lls_sub[0].sub_stripe,
                                                      got, need);
-        } else if (io->ci_type != CIT_TRUNC && io->ci_type != CIT_MISC &&
+        } else if (io->ci_type != CIT_SETATTR && io->ci_type != CIT_MISC &&
                    !cl_io_is_append(io) && need->cld_mode != CLM_PHANTOM)
                 /*
                  * Multi-stripe locks are only suitable for `quick' IO and for
@@ -1050,7 +1054,7 @@ static int lov_lock_fits_into(const struct lu_env *env,
                  * match against original lock extent.
                  */
                 result = cl_lock_ext_match(&lov->lls_orig, need);
-        CDEBUG(D_DLMTRACE, DDESCR"/"DDESCR" %i %i/%i: %i\n",
+        CDEBUG(D_DLMTRACE, DDESCR"/"DDESCR" %d %d/%d: %d\n",
                PDESCR(&lov->lls_orig), PDESCR(&lov->lls_sub[0].sub_got),
                lov->lls_sub[0].sub_stripe, lov->lls_nr, lov_r0(obj)->lo_nr,
                result);
@@ -1114,44 +1118,40 @@ static void lov_lock_delete(const struct lu_env *env,
 {
         struct lov_lock        *lck     = cl2lov_lock(slice);
         struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
-        int i;
+        struct lov_lock_link   *link;
+        int                     rc;
+        int                     i;
 
         LASSERT(slice->cls_lock->cll_state == CLS_FREEING);
         ENTRY;
 
         for (i = 0; i < lck->lls_nr; ++i) {
-                struct lov_lock_sub *lls;
-                struct lovsub_lock  *lsl;
-                struct cl_lock      *sublock;
-                int rc;
+                struct lov_lock_sub *lls = &lck->lls_sub[i];
+                struct lovsub_lock  *lsl = lls->sub_lock;
 
-                lls = &lck->lls_sub[i];
-                lsl = lls->sub_lock;
-                if (lsl == NULL)
+                if (lsl == NULL) /* already removed */
                         continue;
 
-                sublock = lsl->lss_cl.cls_lock;
                 rc = lov_sublock_lock(env, lck, lls, closure, NULL);
-                if (rc == 0) {
-                        if (lls->sub_flags & LSF_HELD)
-                                lov_sublock_release(env, lck, i, 1, 0);
-                        if (sublock->cll_state < CLS_FREEING) {
-                                struct lov_lock_link *link;
-
-                                link = lov_lock_link_find(env, lck, lsl);
-                                LASSERT(link != NULL);
-                                lov_lock_unlink(env, link, lsl);
-                                LASSERT(lck->lls_sub[i].sub_lock == NULL);
-                        }
-                        lov_sublock_unlock(env, lsl, closure, NULL);
-                } else if (rc == CLO_REPEAT) {
-                        --i; /* repeat with this lock */
-                } else {
-                        CL_LOCK_DEBUG(D_ERROR, env, sublock,
-                                      "Cannot get sub-lock for delete: %i\n",
-                                      rc);
+                if (rc == CLO_REPEAT) {
+                        --i;
+                        continue;
                 }
+
+                LASSERT(rc == 0);
+                LASSERT(lsl->lss_cl.cls_lock->cll_state < CLS_FREEING);
+
+                if (lls->sub_flags & LSF_HELD)
+                        lov_sublock_release(env, lck, i, 1, 0);
+
+                link = lov_lock_link_find(env, lck, lsl);
+                LASSERT(link != NULL);
+                lov_lock_unlink(env, link, lsl);
+                LASSERT(lck->lls_sub[i].sub_lock == NULL);
+
+                lov_sublock_unlock(env, lsl, closure, NULL);
         }
+
         cl_lock_closure_fini(closure);
         EXIT;
 }
@@ -1196,7 +1196,7 @@ int lov_lock_init_raid0(const struct lu_env *env, struct cl_object *obj,
         int result;
 
         ENTRY;
-        OBD_SLAB_ALLOC_PTR_GFP(lck, lov_lock_kmem, CFS_ALLOC_IO);
+       OBD_SLAB_ALLOC_PTR_GFP(lck, lov_lock_kmem, __GFP_IO);
         if (lck != NULL) {
                 cl_lock_slice_add(lock, &lck->lls_cl, obj, &lov_lock_ops);
                 result = lov_lock_sub_init(env, lck, io);
@@ -1205,6 +1205,42 @@ int lov_lock_init_raid0(const struct lu_env *env, struct cl_object *obj,
         RETURN(result);
 }
 
+static void lov_empty_lock_fini(const struct lu_env *env,
+                               struct cl_lock_slice *slice)
+{
+       struct lov_lock *lck = cl2lov_lock(slice);
+       OBD_SLAB_FREE_PTR(lck, lov_lock_kmem);
+}
+
+static int lov_empty_lock_print(const struct lu_env *env, void *cookie,
+                       lu_printer_t p, const struct cl_lock_slice *slice)
+{
+       (*p)(env, cookie, "empty\n");
+       return 0;
+}
+
+/* XXX: more methods will be added later. */
+static const struct cl_lock_operations lov_empty_lock_ops = {
+       .clo_fini  = lov_empty_lock_fini,
+       .clo_print = lov_empty_lock_print
+};
+
+int lov_lock_init_empty(const struct lu_env *env, struct cl_object *obj,
+               struct cl_lock *lock, const struct cl_io *io)
+{
+       struct lov_lock *lck;
+       int result = -ENOMEM;
+
+       ENTRY;
+       OBD_SLAB_ALLOC_PTR_GFP(lck, lov_lock_kmem, __GFP_IO);
+       if (lck != NULL) {
+               cl_lock_slice_add(lock, &lck->lls_cl, obj, &lov_empty_lock_ops);
+               lck->lls_orig = lock->cll_descr;
+               result = 0;
+       }
+       RETURN(result);
+}
+
 static struct cl_lock_closure *lov_closure_get(const struct lu_env *env,
                                                struct cl_lock *parent)
 {