staging/lustre/clio: generalize cl_sync_io

To make cl_sync_io interfaces not just wait for pages, but to be
a generic synchronization mechanism.

Also remove cl_io_cancel that became not used.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-on: http://review.whamcloud.com/8656
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4198
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lustre/include/cl_object.h b/drivers/staging/lustre/lustre/include/cl_object.h
index 69b40f5..91261b1 100644 (file)
--- a/drivers/staging/lustre/lustre/include/cl_object.h
+++ b/drivers/staging/lustre/lustre/include/cl_object.h
@@ -3125,13 +3125,18 @@ struct cl_sync_io {
        atomic_t                csi_barrier;
        /** completion to be signaled when transfer is complete. */
        wait_queue_head_t               csi_waitq;
+       /** callback to invoke when this IO is finished */
+       void                    (*csi_end_io)(const struct lu_env *,
+                                             struct cl_sync_io *);
 };
 
-void cl_sync_io_init(struct cl_sync_io *anchor, int nrpages);
-int  cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
-                    struct cl_page_list *queue, struct cl_sync_io *anchor,
+void cl_sync_io_init(struct cl_sync_io *anchor, int nr,
+                    void (*end)(const struct lu_env *, struct cl_sync_io *));
+int  cl_sync_io_wait(const struct lu_env *env, struct cl_sync_io *anchor,
                     long timeout);
-void cl_sync_io_note(struct cl_sync_io *anchor, int ioret);
+void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
+                    int ioret);
+void cl_sync_io_end(const struct lu_env *env, struct cl_sync_io *anchor);
 
 /** @} cl_sync_io */
 

diff --git a/drivers/staging/lustre/lustre/obdclass/cl_io.c b/drivers/staging/lustre/lustre/obdclass/cl_io.c
index 65d6cee..6a8dd9f 100644 (file)
--- a/drivers/staging/lustre/lustre/obdclass/cl_io.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_io.c
@@ -800,6 +800,9 @@ int cl_io_submit_rw(const struct lu_env *env, struct cl_io *io,
 }
 EXPORT_SYMBOL(cl_io_submit_rw);
 
+static void cl_page_list_assume(const struct lu_env *env,
+                               struct cl_io *io, struct cl_page_list *plist);
+
 /**
  * Submit a sync_io and wait for the IO to be finished, or error happens.
  * If \a timeout is zero, it means to wait for the IO unconditionally.
@@ -817,7 +820,7 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
                pg->cp_sync_io = anchor;
        }
 
-       cl_sync_io_init(anchor, queue->c2_qin.pl_nr);
+       cl_sync_io_init(anchor, queue->c2_qin.pl_nr, &cl_sync_io_end);
        rc = cl_io_submit_rw(env, io, iot, queue);
        if (rc == 0) {
                /*
@@ -828,12 +831,12 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
                 */
                cl_page_list_for_each(pg, &queue->c2_qin) {
                        pg->cp_sync_io = NULL;
-                       cl_sync_io_note(anchor, 1);
+                       cl_sync_io_note(env, anchor, 1);
                }
 
                /* wait for the IO to be finished. */
-               rc = cl_sync_io_wait(env, io, &queue->c2_qout,
-                                    anchor, timeout);
+               rc = cl_sync_io_wait(env, anchor, timeout);
+               cl_page_list_assume(env, io, &queue->c2_qout);
        } else {
                LASSERT(list_empty(&queue->c2_qout.pl_pages));
                cl_page_list_for_each(pg, &queue->c2_qin)
@@ -844,25 +847,6 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
 EXPORT_SYMBOL(cl_io_submit_sync);
 
 /**
- * Cancel an IO which has been submitted by cl_io_submit_rw.
- */
-static int cl_io_cancel(const struct lu_env *env, struct cl_io *io,
-                       struct cl_page_list *queue)
-{
-       struct cl_page *page;
-       int result = 0;
-
-       CERROR("Canceling ongoing page transmission\n");
-       cl_page_list_for_each(page, queue) {
-               int rc;
-
-               rc = cl_page_cancel(env, page);
-               result = result ?: rc;
-       }
-       return result;
-}
-
-/**
  * Main io loop.
  *
  * Pumps io through iterations calling
@@ -1433,25 +1417,38 @@ void cl_req_attr_set(const struct lu_env *env, struct cl_req *req,
 }
 EXPORT_SYMBOL(cl_req_attr_set);
 
+/* cl_sync_io_callback assumes the caller must call cl_sync_io_wait() to
+ * wait for the IO to finish.
+ */
+void cl_sync_io_end(const struct lu_env *env, struct cl_sync_io *anchor)
+{
+       wake_up_all(&anchor->csi_waitq);
+
+       /* it's safe to nuke or reuse anchor now */
+       atomic_set(&anchor->csi_barrier, 0);
+}
+EXPORT_SYMBOL(cl_sync_io_end);
 
 /**
- * Initialize synchronous io wait anchor, for transfer of \a nrpages pages.
+ * Initialize synchronous io wait anchor
  */
-void cl_sync_io_init(struct cl_sync_io *anchor, int nrpages)
+void cl_sync_io_init(struct cl_sync_io *anchor, int nr,
+                    void (*end)(const struct lu_env *, struct cl_sync_io *))
 {
        init_waitqueue_head(&anchor->csi_waitq);
-       atomic_set(&anchor->csi_sync_nr, nrpages);
-       atomic_set(&anchor->csi_barrier, nrpages > 0);
+       atomic_set(&anchor->csi_sync_nr, nr);
+       atomic_set(&anchor->csi_barrier, nr > 0);
        anchor->csi_sync_rc = 0;
+       anchor->csi_end_io = end;
+       LASSERT(end);
 }
 EXPORT_SYMBOL(cl_sync_io_init);
 
 /**
- * Wait until all transfer completes. Transfer completion routine has to call
- * cl_sync_io_note() for every page.
+ * Wait until all IO completes. Transfer completion routine has to call
+ * cl_sync_io_note() for every entity.
  */
-int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
-                   struct cl_page_list *queue, struct cl_sync_io *anchor,
+int cl_sync_io_wait(const struct lu_env *env, struct cl_sync_io *anchor,
                    long timeout)
 {
        struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(timeout),
@@ -1464,11 +1461,9 @@ int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
                          atomic_read(&anchor->csi_sync_nr) == 0,
                          &lwi);
        if (rc < 0) {
-               CERROR("SYNC IO failed with error: %d, try to cancel %d remaining pages\n",
+               CERROR("IO failed: %d, still wait for %d remaining entries\n",
                       rc, atomic_read(&anchor->csi_sync_nr));
 
-               (void)cl_io_cancel(env, io, queue);
-
                lwi = (struct l_wait_info) { 0 };
                (void)l_wait_event(anchor->csi_waitq,
                                   atomic_read(&anchor->csi_sync_nr) == 0,
@@ -1477,14 +1472,12 @@ int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
                rc = anchor->csi_sync_rc;
        }
        LASSERT(atomic_read(&anchor->csi_sync_nr) == 0);
-       cl_page_list_assume(env, io, queue);
 
        /* wait until cl_sync_io_note() has done wakeup */
        while (unlikely(atomic_read(&anchor->csi_barrier) != 0)) {
                cpu_relax();
        }
 
-       POISON(anchor, 0x5a, sizeof(*anchor));
        return rc;
 }
 EXPORT_SYMBOL(cl_sync_io_wait);
@@ -1492,7 +1485,8 @@ EXPORT_SYMBOL(cl_sync_io_wait);
 /**
  * Indicate that transfer of a single page completed.
  */
-void cl_sync_io_note(struct cl_sync_io *anchor, int ioret)
+void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
+                    int ioret)
 {
        if (anchor->csi_sync_rc == 0 && ioret < 0)
                anchor->csi_sync_rc = ioret;
@@ -1503,9 +1497,9 @@ void cl_sync_io_note(struct cl_sync_io *anchor, int ioret)
         */
        LASSERT(atomic_read(&anchor->csi_sync_nr) > 0);
        if (atomic_dec_and_test(&anchor->csi_sync_nr)) {
-               wake_up_all(&anchor->csi_waitq);
-               /* it's safe to nuke or reuse anchor now */
-               atomic_set(&anchor->csi_barrier, 0);
+               LASSERT(anchor->csi_end_io);
+               anchor->csi_end_io(env, anchor);
+               /* Can't access anchor any more */
        }
 }
 EXPORT_SYMBOL(cl_sync_io_note);

diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c
index 506a9f9..ad7f0ae 100644 (file)
--- a/drivers/staging/lustre/lustre/obdclass/cl_page.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_page.c
@@ -887,7 +887,7 @@ void cl_page_completion(const struct lu_env *env,
        cl_page_put(env, pg);
 
        if (anchor)
-               cl_sync_io_note(anchor, ioret);
+               cl_sync_io_note(env, anchor, ioret);
 }
 EXPORT_SYMBOL(cl_page_completion);