#include <linux/list.h>
#include "ldlm_internal.h"
-int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
- void *data, int flag);
-
/**
* list_for_remaining_safe - iterate over the remaining entries in a list
* and safeguard against removal of a list entry.
lock->l_policy_data.l_flock.start));
}
-static inline void ldlm_flock_blocking_link(struct ldlm_lock *req,
- struct ldlm_lock *lock)
-{
- /* For server only */
- if (req->l_export == NULL)
- return;
-
- LASSERT(hlist_unhashed(&req->l_exp_flock_hash));
-
- req->l_policy_data.l_flock.blocking_owner =
- lock->l_policy_data.l_flock.owner;
- req->l_policy_data.l_flock.blocking_export =
- lock->l_export;
- req->l_policy_data.l_flock.blocking_refs = 0;
-
- cfs_hash_add(req->l_export->exp_flock_hash,
- &req->l_policy_data.l_flock.owner,
- &req->l_exp_flock_hash);
-}
-
-static inline void ldlm_flock_blocking_unlink(struct ldlm_lock *req)
-{
- /* For server only */
- if (req->l_export == NULL)
- return;
-
- check_res_locked(req->l_resource);
- if (req->l_export->exp_flock_hash != NULL &&
- !hlist_unhashed(&req->l_exp_flock_hash))
- cfs_hash_del(req->l_export->exp_flock_hash,
- &req->l_policy_data.l_flock.owner,
- &req->l_exp_flock_hash);
-}
-
static inline void
ldlm_flock_destroy(struct ldlm_lock *lock, ldlm_mode_t mode, __u64 flags)
{
ldlm_lock_destroy_nolock(lock);
}
-/**
- * POSIX locks deadlock detection code.
- *
- * Given a new lock \a req and an existing lock \a bl_lock it conflicts
- * with, we need to iterate through all blocked POSIX locks for this
- * export and see if there is a deadlock condition arising. (i.e. when
- * one client holds a lock on something and want a lock on something
- * else and at the same time another client has the opposite situation).
- */
-static int
-ldlm_flock_deadlock(struct ldlm_lock *req, struct ldlm_lock *bl_lock)
-{
- struct obd_export *req_exp = req->l_export;
- struct obd_export *bl_exp = bl_lock->l_export;
- __u64 req_owner = req->l_policy_data.l_flock.owner;
- __u64 bl_owner = bl_lock->l_policy_data.l_flock.owner;
-
- /* For server only */
- if (req_exp == NULL)
- return 0;
-
- class_export_get(bl_exp);
- while (1) {
- struct obd_export *bl_exp_new;
- struct ldlm_lock *lock = NULL;
- struct ldlm_flock *flock;
-
- if (bl_exp->exp_flock_hash != NULL)
- lock = cfs_hash_lookup(bl_exp->exp_flock_hash,
- &bl_owner);
- if (lock == NULL)
- break;
-
- LASSERT(req != lock);
- flock = &lock->l_policy_data.l_flock;
- LASSERT(flock->owner == bl_owner);
- bl_owner = flock->blocking_owner;
- bl_exp_new = class_export_get(flock->blocking_export);
- class_export_put(bl_exp);
-
- cfs_hash_put(bl_exp->exp_flock_hash, &lock->l_exp_flock_hash);
- bl_exp = bl_exp_new;
-
- if (bl_owner == req_owner && bl_exp == req_exp) {
- class_export_put(bl_exp);
- return 1;
- }
- }
- class_export_put(bl_exp);
-
- return 0;
-}
-
-static void ldlm_flock_cancel_on_deadlock(struct ldlm_lock *lock,
- struct list_head *work_list)
-{
- CDEBUG(D_INFO, "reprocess deadlock req=%p\n", lock);
-
- if ((exp_connect_flags(lock->l_export) &
- OBD_CONNECT_FLOCK_DEAD) == 0) {
- CERROR(
- "deadlock found, but client doesn't support flock canceliation\n");
- } else {
- LASSERT(lock->l_completion_ast);
- LASSERT((lock->l_flags & LDLM_FL_AST_SENT) == 0);
- lock->l_flags |= LDLM_FL_AST_SENT | LDLM_FL_CANCEL_ON_BLOCK |
- LDLM_FL_FLOCK_DEADLOCK;
- ldlm_flock_blocking_unlink(lock);
- ldlm_resource_unlink_lock(lock);
- ldlm_add_ast_work_item(lock, NULL, work_list);
- }
-}
-
/**
* Process a granting attempt for flock lock.
* Must be called under ns lock held.
* - blocking ASTs have not been sent yet, so list of conflicting locks
* would be collected and ASTs sent.
*/
-int
-ldlm_process_flock_lock(struct ldlm_lock *req, __u64 *flags, int first_enq,
- ldlm_error_t *err, struct list_head *work_list)
+static int ldlm_process_flock_lock(struct ldlm_lock *req, __u64 *flags,
+ int first_enq, ldlm_error_t *err,
+ struct list_head *work_list)
{
struct ldlm_resource *res = req->l_resource;
struct ldlm_namespace *ns = ldlm_res_to_ns(res);
struct ldlm_lock *new = req;
struct ldlm_lock *new2 = NULL;
ldlm_mode_t mode = req->l_req_mode;
- int local = ns_is_client(ns);
int added = (mode == LCK_NL);
int overlaps = 0;
int splitted = 0;
*err = ELDLM_OK;
- if (local) {
- /* No blocking ASTs are sent to the clients for
- * Posix file & record locks */
- req->l_blocking_ast = NULL;
- } else {
- /* Called on the server for lock cancels. */
- req->l_blocking_ast = ldlm_flock_blocking_ast;
- }
+ /* No blocking ASTs are sent to the clients for
+ * Posix file & record locks */
+ req->l_blocking_ast = NULL;
reprocess:
if ((*flags == LDLM_FL_WAIT_NOREPROC) || (mode == LCK_NL)) {
if (!first_enq) {
reprocess_failed = 1;
- if (ldlm_flock_deadlock(req, lock)) {
- ldlm_flock_cancel_on_deadlock(req,
- work_list);
- return LDLM_ITER_CONTINUE;
- }
continue;
}
return LDLM_ITER_STOP;
}
- /* add lock to blocking list before deadlock
- * check to prevent race */
- ldlm_flock_blocking_link(req, lock);
-
- if (ldlm_flock_deadlock(req, lock)) {
- ldlm_flock_blocking_unlink(req);
- ldlm_flock_destroy(req, mode, *flags);
- *err = -EDEADLK;
- return LDLM_ITER_STOP;
- }
-
ldlm_resource_add_lock(res, &res->lr_waiting, req);
*flags |= LDLM_FL_BLOCK_GRANTED;
return LDLM_ITER_STOP;
return LDLM_ITER_STOP;
}
- /* In case we had slept on this lock request take it off of the
- * deadlock detection hash list. */
- ldlm_flock_blocking_unlink(req);
-
/* Scan the locks owned by this process that overlap this request.
* We may have to merge or split existing locks. */
/* At this point we're granting the lock request. */
req->l_granted_mode = req->l_req_mode;
- /* Add req to the granted queue before calling ldlm_reprocess_all(). */
if (!added) {
list_del_init(&req->l_res_link);
/* insert new lock before ownlocks in list. */
lock = ((struct ldlm_flock_wait_data *)data)->fwd_lock;
- /* take lock off the deadlock detection hash list. */
lock_res_and_lock(lock);
- ldlm_flock_blocking_unlink(lock);
/* client side - set flag to prevent lock from being put on LRU list */
lock->l_flags |= LDLM_FL_CBPENDING;
(LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) {
if (lock->l_req_mode == lock->l_granted_mode &&
lock->l_granted_mode != LCK_NL &&
- NULL == data)
+ data == NULL)
ldlm_lock_decref_internal(lock, lock->l_req_mode);
/* Need to wake up the waiter if we were evicted */
if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
LDLM_FL_BLOCK_CONV))) {
- if (NULL == data)
+ if (data == NULL)
/* mds granted the lock in the reply */
goto granted;
/* CP AST RPC: lock get granted, wake it up */
obd = class_exp2obd(lock->l_conn_export);
/* if this is a local lock, there is no import */
- if (NULL != obd)
+ if (obd != NULL)
imp = obd->u.cli.cl_import;
- if (NULL != imp) {
+ if (imp != NULL) {
spin_lock(&imp->imp_lock);
fwd.fwd_generation = imp->imp_generation;
spin_unlock(&imp->imp_lock);
lock_res_and_lock(lock);
- /* take lock off the deadlock detection hash list. */
- ldlm_flock_blocking_unlink(lock);
-
/* ldlm_lock_enqueue() has already placed lock on the granted list. */
list_del_init(&lock->l_res_link);
}
EXPORT_SYMBOL(ldlm_flock_completion_ast);
-int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
- void *data, int flag)
-{
- LASSERT(lock);
- LASSERT(flag == LDLM_CB_CANCELING);
-
- /* take lock off the deadlock detection hash list. */
- lock_res_and_lock(lock);
- ldlm_flock_blocking_unlink(lock);
- unlock_res_and_lock(lock);
- return 0;
-}
-
void ldlm_flock_policy_wire18_to_local(const ldlm_wire_policy_data_t *wpolicy,
ldlm_policy_data_t *lpolicy)
{
lpolicy->l_flock.owner = wpolicy->l_flock.lfw_pid;
}
-
void ldlm_flock_policy_wire21_to_local(const ldlm_wire_policy_data_t *wpolicy,
ldlm_policy_data_t *lpolicy)
{
wpolicy->l_flock.lfw_pid = lpolicy->l_flock.pid;
wpolicy->l_flock.lfw_owner = lpolicy->l_flock.owner;
}
-
-/*
- * Export handle<->flock hash operations.
- */
-static unsigned
-ldlm_export_flock_hash(struct cfs_hash *hs, const void *key, unsigned mask)
-{
- return cfs_hash_u64_hash(*(__u64 *)key, mask);
-}
-
-static void *
-ldlm_export_flock_key(struct hlist_node *hnode)
-{
- struct ldlm_lock *lock;
-
- lock = hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash);
- return &lock->l_policy_data.l_flock.owner;
-}
-
-static int
-ldlm_export_flock_keycmp(const void *key, struct hlist_node *hnode)
-{
- return !memcmp(ldlm_export_flock_key(hnode), key, sizeof(__u64));
-}
-
-static void *
-ldlm_export_flock_object(struct hlist_node *hnode)
-{
- return hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash);
-}
-
-static void
-ldlm_export_flock_get(struct cfs_hash *hs, struct hlist_node *hnode)
-{
- struct ldlm_lock *lock;
- struct ldlm_flock *flock;
-
- lock = hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash);
- LDLM_LOCK_GET(lock);
-
- flock = &lock->l_policy_data.l_flock;
- LASSERT(flock->blocking_export != NULL);
- class_export_get(flock->blocking_export);
- flock->blocking_refs++;
-}
-
-static void
-ldlm_export_flock_put(struct cfs_hash *hs, struct hlist_node *hnode)
-{
- struct ldlm_lock *lock;
- struct ldlm_flock *flock;
-
- lock = hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash);
- LDLM_LOCK_RELEASE(lock);
-
- flock = &lock->l_policy_data.l_flock;
- LASSERT(flock->blocking_export != NULL);
- class_export_put(flock->blocking_export);
- if (--flock->blocking_refs == 0) {
- flock->blocking_owner = 0;
- flock->blocking_export = NULL;
- }
-}
-
-static cfs_hash_ops_t ldlm_export_flock_ops = {
- .hs_hash = ldlm_export_flock_hash,
- .hs_key = ldlm_export_flock_key,
- .hs_keycmp = ldlm_export_flock_keycmp,
- .hs_object = ldlm_export_flock_object,
- .hs_get = ldlm_export_flock_get,
- .hs_put = ldlm_export_flock_put,
- .hs_put_locked = ldlm_export_flock_put,
-};
-
-int ldlm_init_flock_export(struct obd_export *exp)
-{
- if (strcmp(exp->exp_obd->obd_type->typ_name, LUSTRE_MDT_NAME) != 0)
- return 0;
-
- exp->exp_flock_hash =
- cfs_hash_create(obd_uuid2str(&exp->exp_client_uuid),
- HASH_EXP_LOCK_CUR_BITS,
- HASH_EXP_LOCK_MAX_BITS,
- HASH_EXP_LOCK_BKT_BITS, 0,
- CFS_HASH_MIN_THETA, CFS_HASH_MAX_THETA,
- &ldlm_export_flock_ops,
- CFS_HASH_DEFAULT | CFS_HASH_NBLK_CHANGE);
- if (!exp->exp_flock_hash)
- return -ENOMEM;
-
- return 0;
-}
-EXPORT_SYMBOL(ldlm_init_flock_export);
-
-void ldlm_destroy_flock_export(struct obd_export *exp)
-{
- if (exp->exp_flock_hash) {
- cfs_hash_putref(exp->exp_flock_hash);
- exp->exp_flock_hash = NULL;
- }
-}
-EXPORT_SYMBOL(ldlm_destroy_flock_export);
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