[PATCH 11/45] staging/lustre/osc: Remove commented out osc_page_protected()

green
2016-02-16T06:01:25Z

The complicated version of osc_page_protected and osc_page_is_dlocked
are unsafe and were commented out for ages, so probably no point in
carrying them on.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
---
drivers/staging/lustre/lustre/osc/osc_page.c | 99 ----------------------------
1 file changed, 99 deletions(-)

diff --git a/drivers/staging/lustre/lustre/osc/osc_page.c b/drivers/staging/lustre/lustre/osc/osc_page.c
index 8943f0a..99d5b56 100644
--- a/drivers/staging/lustre/lustre/osc/osc_page.c
+++ b/drivers/staging/lustre/lustre/osc/osc_page.c
@@ -51,111 +51,12 @@ static int osc_lru_reserve(const struct lu_env *env, struct osc_object *obj,
* @{
*/

-/*
- * Comment out osc_page_protected because it may sleep inside the
- * the client_obd_list_lock.
- * client_obd_list_lock -> osc_ap_completion -> osc_completion ->
- * -> osc_page_protected -> osc_page_is_dlocked -> osc_match_base
- * -> ldlm_lock_match -> sptlrpc_import_check_ctx -> sleep.
- */
-#if 0
-static int osc_page_is_dlocked(const struct lu_env *env,
- const struct osc_page *opg,
- enum cl_lock_mode mode, int pending, int unref)
-{
- struct cl_page *page;
- struct osc_object *obj;
- struct osc_thread_info *info;
- struct ldlm_res_id *resname;
- struct lustre_handle *lockh;
- ldlm_policy_data_t *policy;
- ldlm_mode_t dlmmode;
- __u64 flags;
-
- might_sleep();
-
- info = osc_env_info(env);
- resname = &info->oti_resname;
- policy = &info->oti_policy;
- lockh = &info->oti_handle;
- page = opg->ops_cl.cpl_page;
- obj = cl2osc(opg->ops_cl.cpl_obj);
-
- flags = LDLM_FL_TEST_LOCK | LDLM_FL_BLOCK_GRANTED;
- if (pending)
- flags |= LDLM_FL_CBPENDING;
-
- dlmmode = osc_cl_lock2ldlm(mode) | LCK_PW;
- osc_lock_build_res(env, obj, resname);
- osc_index2policy(policy, page->cp_obj, page->cp_index, page->cp_index);
- return osc_match_base(osc_export(obj), resname, LDLM_EXTENT, policy,
- dlmmode, &flags, NULL, lockh, unref);
-}
-
-/**
- * Checks an invariant that a page in the cache is covered by a lock, as
- * needed.
- */
-static int osc_page_protected(const struct lu_env *env,
- const struct osc_page *opg,
- enum cl_lock_mode mode, int unref)
-{
- struct cl_object_header *hdr;
- struct cl_lock *scan;
- struct cl_page *page;
- struct cl_lock_descr *descr;
- int result;
-
- LINVRNT(!opg->ops_temp);
-
- page = opg->ops_cl.cpl_page;
- if (page->cp_owner != NULL &&
- cl_io_top(page->cp_owner)->ci_lockreq == CILR_NEVER)
- /*
- * If IO is done without locks (liblustre, or lloop), lock is
- * not required.
- */
- result = 1;
- else
- /* otherwise check for a DLM lock */
- result = osc_page_is_dlocked(env, opg, mode, 1, unref);
- if (result == 0) {
- /* maybe this page is a part of a lockless io? */
- hdr = cl_object_header(opg->ops_cl.cpl_obj);
- descr = &osc_env_info(env)->oti_descr;
- descr->cld_mode = mode;
- descr->cld_start = page->cp_index;
- descr->cld_end = page->cp_index;
- spin_lock(&hdr->coh_lock_guard);
- list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) {
- /*
- * Lock-less sub-lock has to be either in HELD state
- * (when io is actively going on), or in CACHED state,
- * when top-lock is being unlocked:
- * cl_io_unlock()->cl_unuse()->...->lov_lock_unuse().
- */
- if ((scan->cll_state == CLS_HELD ||
- scan->cll_state == CLS_CACHED) &&
- cl_lock_ext_match(&scan->cll_descr, descr)) {
- struct osc_lock *olck;
-
- olck = osc_lock_at(scan);
- result = osc_lock_is_lockless(olck);
- break;
- }
- }
- spin_unlock(&hdr->coh_lock_guard);
- }
- return result;
-}
-#else
static int osc_page_protected(const struct lu_env *env,
const struct osc_page *opg,
enum cl_lock_mode mode, int unref)
{
return 1;
}
-#endif

/*****************************************************************************
*
--
2.1.0