*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
*
* GPL HEADER END
*/
* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
*
- * Copyright (c) 2011, 2014, Intel Corporation.
+ * Copyright (c) 2011, 2017, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
* Lustre is a trademark of Sun Microsystems, Inc.
*
- * glimpse code shared between vvp and liblustre (and other Lustre clients in
- * the future).
+ * glimpse code used by vvp (and other Lustre clients in the future).
*
* Author: Nikita Danilov <nikita.danilov@sun.com>
* Author: Oleg Drokin <oleg.drokin@sun.com>
CDEBUG(D_DLMTRACE, "Glimpsing inode "DFID"\n", PFID(fid));
/* NOTE: this looks like DLM lock request, but it may
- * not be one. Due to CEF_ASYNC flag (translated
+ * not be one. Due to CEF_GLIMPSE flag (translated
* to LDLM_FL_HAS_INTENT by osc), this is
* glimpse request, that won't revoke any
* conflicting DLM locks held. Instead,
*descr = whole_file;
descr->cld_obj = clob;
descr->cld_mode = CLM_READ;
- descr->cld_enq_flags = CEF_ASYNC | CEF_MUST;
+ descr->cld_enq_flags = CEF_GLIMPSE | CEF_MUST;
if (agl)
- descr->cld_enq_flags |= CEF_AGL;
+ descr->cld_enq_flags |= CEF_SPECULATIVE | CEF_NONBLOCK;
/*
- * CEF_ASYNC is used because glimpse sub-locks cannot
- * deadlock (because they never conflict with other
- * locks) and, hence, can be enqueued out-of-order.
- *
* CEF_MUST protects glimpse lock from conversion into
* a lockless mode.
*/
RETURN(result);
}
-static int cl_io_get(struct inode *inode, struct lu_env **envout,
- struct cl_io **ioout, int *refcheck)
+/**
+ * Get an IO environment for special operations such as glimpse locks and
+ * manually requested locks (ladvise lockahead)
+ *
+ * \param[in] inode inode the operation is being performed on
+ * \param[out] envout thread specific execution environment
+ * \param[out] ioout client io description
+ * \param[out] refcheck reference check
+ *
+ * \retval 1 on success
+ * \retval 0 not a regular file, cannot get environment
+ * \retval negative negative errno on error
+ */
+int cl_io_get(struct inode *inode, struct lu_env **envout,
+ struct cl_io **ioout, __u16 *refcheck)
{
struct lu_env *env;
struct cl_io *io;
*/
struct lu_env *env = NULL;
struct cl_io *io = NULL;
- int result;
- int refcheck;
-
- ENTRY;
-
- result = cl_io_get(inode, &env, &io, &refcheck);
- if (result > 0) {
- again:
- io->ci_verify_layout = 1;
- result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
- if (result > 0)
- /*
- * nothing to do for this io. This currently happens
- * when stripe sub-object's are not yet created.
- */
- result = io->ci_result;
- else if (result == 0)
- result = cl_glimpse_lock(env, io, inode, io->ci_obj,
- agl);
+ __u16 refcheck;
+ int retried = 0;
+ int result;
+
+ ENTRY;
+
+ result = cl_io_get(inode, &env, &io, &refcheck);
+ if (result <= 0)
+ RETURN(result);
+
+ do {
+ io->ci_ndelay_tried = retried++;
+ io->ci_ndelay = io->ci_verify_layout = 1;
+ result = cl_io_init(env, io, CIT_GLIMPSE, io->ci_obj);
+ if (result > 0) {
+ /*
+ * nothing to do for this io. This currently happens
+ * when stripe sub-object's are not yet created.
+ */
+ result = io->ci_result;
+ } else if (result == 0) {
+ result = cl_glimpse_lock(env, io, inode, io->ci_obj,
+ agl);
+ if (!agl && result == -EWOULDBLOCK)
+ io->ci_need_restart = 1;
+ }
OBD_FAIL_TIMEOUT(OBD_FAIL_GLIMPSE_DELAY, 2);
- cl_io_fini(env, io);
- if (unlikely(io->ci_need_restart))
- goto again;
- cl_env_put(env, &refcheck);
- }
+ cl_io_fini(env, io);
+ } while (unlikely(io->ci_need_restart));
+
+ cl_env_put(env, &refcheck);
RETURN(result);
}