#include <trace/events/dlm.h>
#include "dlm_internal.h"
+#include "memory.h"
#include "lock.h"
#include "user.h"
#include "ast.h"
-static uint64_t dlm_cb_seq;
-static DEFINE_SPINLOCK(dlm_cb_seq_spin);
+void dlm_release_callback(struct kref *ref)
+{
+ struct dlm_callback *cb = container_of(ref, struct dlm_callback, ref);
+
+ dlm_free_cb(cb);
+}
+
+void dlm_callback_set_last_ptr(struct dlm_callback **from,
+ struct dlm_callback *to)
+{
+ if (*from)
+ kref_put(&(*from)->ref, dlm_release_callback);
+
+ if (to)
+ kref_get(&to->ref);
+
+ *from = to;
+}
-static void dlm_dump_lkb_callbacks(struct dlm_lkb *lkb)
+void dlm_purge_lkb_callbacks(struct dlm_lkb *lkb)
{
- int i;
-
- log_print("last_bast %x %llu flags %x mode %d sb %d %x",
- lkb->lkb_id,
- (unsigned long long)lkb->lkb_last_bast.seq,
- lkb->lkb_last_bast.flags,
- lkb->lkb_last_bast.mode,
- lkb->lkb_last_bast.sb_status,
- lkb->lkb_last_bast.sb_flags);
-
- log_print("last_cast %x %llu flags %x mode %d sb %d %x",
- lkb->lkb_id,
- (unsigned long long)lkb->lkb_last_cast.seq,
- lkb->lkb_last_cast.flags,
- lkb->lkb_last_cast.mode,
- lkb->lkb_last_cast.sb_status,
- lkb->lkb_last_cast.sb_flags);
-
- for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
- log_print("cb %x %llu flags %x mode %d sb %d %x",
- lkb->lkb_id,
- (unsigned long long)lkb->lkb_callbacks[i].seq,
- lkb->lkb_callbacks[i].flags,
- lkb->lkb_callbacks[i].mode,
- lkb->lkb_callbacks[i].sb_status,
- lkb->lkb_callbacks[i].sb_flags);
+ struct dlm_callback *cb, *safe;
+
+ list_for_each_entry_safe(cb, safe, &lkb->lkb_callbacks, list) {
+ list_del(&cb->list);
+ kref_put(&cb->ref, dlm_release_callback);
}
+
+ /* TODO */
+ lkb->lkb_flags &= ~DLM_IFL_NEED_SCHED;
+
+ /* invalidate */
+ dlm_callback_set_last_ptr(&lkb->lkb_last_cast, NULL);
+ dlm_callback_set_last_ptr(&lkb->lkb_last_cb, NULL);
+ lkb->lkb_last_bast_mode = -1;
}
-int dlm_add_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
- int status, uint32_t sbflags, uint64_t seq)
+int dlm_enqueue_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
+ int status, uint32_t sbflags)
{
struct dlm_ls *ls = lkb->lkb_resource->res_ls;
- uint64_t prev_seq;
+ int rv = DLM_ENQUEUE_CALLBACK_SUCCESS;
+ struct dlm_callback *cb;
int prev_mode;
- int i, rv;
- for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
- if (lkb->lkb_callbacks[i].seq)
- continue;
+ if (flags & DLM_CB_BAST) {
+ /* if cb is a bast, it should be skipped if the blocking mode is
+ * compatible with the last granted mode
+ */
+ if (lkb->lkb_last_cast) {
+ if (dlm_modes_compat(mode, lkb->lkb_last_cast->mode)) {
+ log_debug(ls, "skip %x bast mode %d for cast mode %d",
+ lkb->lkb_id, mode,
+ lkb->lkb_last_cast->mode);
+ goto out;
+ }
+ }
/*
* Suppress some redundant basts here, do more on removal.
* is a bast for the same mode or a more restrictive mode.
* (the addional > PR check is needed for PR/CW inversion)
*/
-
- if ((i > 0) && (flags & DLM_CB_BAST) &&
- (lkb->lkb_callbacks[i-1].flags & DLM_CB_BAST)) {
-
- prev_seq = lkb->lkb_callbacks[i-1].seq;
- prev_mode = lkb->lkb_callbacks[i-1].mode;
+ if (lkb->lkb_last_cb && lkb->lkb_last_cb->flags & DLM_CB_BAST) {
+ prev_mode = lkb->lkb_last_cb->mode;
if ((prev_mode == mode) ||
(prev_mode > mode && prev_mode > DLM_LOCK_PR)) {
-
- log_debug(ls, "skip %x add bast %llu mode %d "
- "for bast %llu mode %d",
- lkb->lkb_id,
- (unsigned long long)seq,
- mode,
- (unsigned long long)prev_seq,
- prev_mode);
- rv = 0;
+ log_debug(ls, "skip %x add bast mode %d for bast mode %d",
+ lkb->lkb_id, mode, prev_mode);
goto out;
}
}
-
- lkb->lkb_callbacks[i].seq = seq;
- lkb->lkb_callbacks[i].flags = flags;
- lkb->lkb_callbacks[i].mode = mode;
- lkb->lkb_callbacks[i].sb_status = status;
- lkb->lkb_callbacks[i].sb_flags = (sbflags & 0x000000FF);
- rv = 0;
- break;
}
- if (i == DLM_CALLBACKS_SIZE) {
- log_error(ls, "no callbacks %x %llu flags %x mode %d sb %d %x",
- lkb->lkb_id, (unsigned long long)seq,
- flags, mode, status, sbflags);
- dlm_dump_lkb_callbacks(lkb);
- rv = -1;
+ cb = dlm_allocate_cb();
+ if (!cb) {
+ rv = DLM_ENQUEUE_CALLBACK_FAILURE;
goto out;
}
- out:
- return rv;
-}
-
-int dlm_rem_lkb_callback(struct dlm_ls *ls, struct dlm_lkb *lkb,
- struct dlm_callback *cb, int *resid)
-{
- int i, rv;
-
- *resid = 0;
-
- if (!lkb->lkb_callbacks[0].seq) {
- rv = -ENOENT;
- goto out;
- }
-
- /* oldest undelivered cb is callbacks[0] */
-
- memcpy(cb, &lkb->lkb_callbacks[0], sizeof(struct dlm_callback));
- memset(&lkb->lkb_callbacks[0], 0, sizeof(struct dlm_callback));
- /* shift others down */
-
- for (i = 1; i < DLM_CALLBACKS_SIZE; i++) {
- if (!lkb->lkb_callbacks[i].seq)
- break;
- memcpy(&lkb->lkb_callbacks[i-1], &lkb->lkb_callbacks[i],
- sizeof(struct dlm_callback));
- memset(&lkb->lkb_callbacks[i], 0, sizeof(struct dlm_callback));
- (*resid)++;
+ cb->flags = flags;
+ cb->mode = mode;
+ cb->sb_status = status;
+ cb->sb_flags = (sbflags & 0x000000FF);
+ kref_init(&cb->ref);
+ if (!(lkb->lkb_flags & DLM_IFL_NEED_SCHED)) {
+ lkb->lkb_flags |= DLM_IFL_NEED_SCHED;
+ rv = DLM_ENQUEUE_CALLBACK_NEED_SCHED;
}
+ list_add_tail(&cb->list, &lkb->lkb_callbacks);
- /* if cb is a bast, it should be skipped if the blocking mode is
- compatible with the last granted mode */
-
- if ((cb->flags & DLM_CB_BAST) && lkb->lkb_last_cast.seq) {
- if (dlm_modes_compat(cb->mode, lkb->lkb_last_cast.mode)) {
- cb->flags |= DLM_CB_SKIP;
-
- log_debug(ls, "skip %x bast %llu mode %d "
- "for cast %llu mode %d",
- lkb->lkb_id,
- (unsigned long long)cb->seq,
- cb->mode,
- (unsigned long long)lkb->lkb_last_cast.seq,
- lkb->lkb_last_cast.mode);
- rv = 0;
- goto out;
- }
- }
+ if (flags & DLM_CB_CAST)
+ dlm_callback_set_last_ptr(&lkb->lkb_last_cast, cb);
- if (cb->flags & DLM_CB_CAST)
- memcpy(&lkb->lkb_last_cast, cb, sizeof(struct dlm_callback));
+ dlm_callback_set_last_ptr(&lkb->lkb_last_cb, cb);
- if (cb->flags & DLM_CB_BAST)
- memcpy(&lkb->lkb_last_bast, cb, sizeof(struct dlm_callback));
- rv = 0;
out:
return rv;
}
+int dlm_dequeue_lkb_callback(struct dlm_lkb *lkb, struct dlm_callback **cb)
+{
+ /* oldest undelivered cb is callbacks first entry */
+ *cb = list_first_entry_or_null(&lkb->lkb_callbacks,
+ struct dlm_callback, list);
+ if (!*cb)
+ return DLM_DEQUEUE_CALLBACK_EMPTY;
+
+ /* remove it from callbacks so shift others down */
+ list_del(&(*cb)->list);
+ if (list_empty(&lkb->lkb_callbacks))
+ return DLM_DEQUEUE_CALLBACK_LAST;
+
+ return DLM_DEQUEUE_CALLBACK_SUCCESS;
+}
+
void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
uint32_t sbflags)
{
struct dlm_ls *ls = lkb->lkb_resource->res_ls;
- uint64_t new_seq, prev_seq;
int rv;
- spin_lock(&dlm_cb_seq_spin);
- new_seq = ++dlm_cb_seq;
- if (!dlm_cb_seq)
- new_seq = ++dlm_cb_seq;
- spin_unlock(&dlm_cb_seq_spin);
-
if (lkb->lkb_flags & DLM_IFL_USER) {
- dlm_user_add_ast(lkb, flags, mode, status, sbflags, new_seq);
+ dlm_user_add_ast(lkb, flags, mode, status, sbflags);
return;
}
spin_lock(&lkb->lkb_cb_lock);
- prev_seq = lkb->lkb_callbacks[0].seq;
-
- rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, new_seq);
- if (rv < 0)
- goto out;
-
- if (!prev_seq) {
+ rv = dlm_enqueue_lkb_callback(lkb, flags, mode, status, sbflags);
+ switch (rv) {
+ case DLM_ENQUEUE_CALLBACK_NEED_SCHED:
kref_get(&lkb->lkb_ref);
spin_lock(&ls->ls_cb_lock);
queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
}
spin_unlock(&ls->ls_cb_lock);
+ break;
+ case DLM_ENQUEUE_CALLBACK_FAILURE:
+ WARN_ON(1);
+ break;
+ case DLM_ENQUEUE_CALLBACK_SUCCESS:
+ break;
+ default:
+ WARN_ON(1);
+ break;
}
- out:
spin_unlock(&lkb->lkb_cb_lock);
}
struct dlm_ls *ls = lkb->lkb_resource->res_ls;
void (*castfn) (void *astparam);
void (*bastfn) (void *astparam, int mode);
- struct dlm_callback callbacks[DLM_CALLBACKS_SIZE];
- int i, rv, resid;
-
- memset(&callbacks, 0, sizeof(callbacks));
+ struct dlm_callback *cb;
+ int rv;
spin_lock(&lkb->lkb_cb_lock);
- if (!lkb->lkb_callbacks[0].seq) {
- /* no callback work exists, shouldn't happen */
- log_error(ls, "dlm_callback_work %x no work", lkb->lkb_id);
- dlm_print_lkb(lkb);
- dlm_dump_lkb_callbacks(lkb);
- }
-
- for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
- rv = dlm_rem_lkb_callback(ls, lkb, &callbacks[i], &resid);
- if (rv < 0)
- break;
- }
-
- if (resid) {
- /* cbs remain, loop should have removed all, shouldn't happen */
- log_error(ls, "dlm_callback_work %x resid %d", lkb->lkb_id,
- resid);
- dlm_print_lkb(lkb);
- dlm_dump_lkb_callbacks(lkb);
- }
+ rv = dlm_dequeue_lkb_callback(lkb, &cb);
spin_unlock(&lkb->lkb_cb_lock);
- castfn = lkb->lkb_astfn;
- bastfn = lkb->lkb_bastfn;
+ if (WARN_ON(rv == DLM_DEQUEUE_CALLBACK_EMPTY))
+ return;
- for (i = 0; i < DLM_CALLBACKS_SIZE; i++) {
- if (!callbacks[i].seq)
- break;
- if (callbacks[i].flags & DLM_CB_SKIP) {
- continue;
- } else if (callbacks[i].flags & DLM_CB_BAST) {
- trace_dlm_bast(ls, lkb, callbacks[i].mode);
+ for (;;) {
+ castfn = lkb->lkb_astfn;
+ bastfn = lkb->lkb_bastfn;
+
+ if (cb->flags & DLM_CB_BAST) {
+ trace_dlm_bast(ls, lkb, cb->mode);
lkb->lkb_last_bast_time = ktime_get();
- bastfn(lkb->lkb_astparam, callbacks[i].mode);
- } else if (callbacks[i].flags & DLM_CB_CAST) {
- lkb->lkb_lksb->sb_status = callbacks[i].sb_status;
- lkb->lkb_lksb->sb_flags = callbacks[i].sb_flags;
+ lkb->lkb_last_bast_mode = cb->mode;
+ bastfn(lkb->lkb_astparam, cb->mode);
+ } else if (cb->flags & DLM_CB_CAST) {
+ lkb->lkb_lksb->sb_status = cb->sb_status;
+ lkb->lkb_lksb->sb_flags = cb->sb_flags;
trace_dlm_ast(ls, lkb);
lkb->lkb_last_cast_time = ktime_get();
castfn(lkb->lkb_astparam);
}
+
+ kref_put(&cb->ref, dlm_release_callback);
+
+ spin_lock(&lkb->lkb_cb_lock);
+ rv = dlm_dequeue_lkb_callback(lkb, &cb);
+ if (rv == DLM_DEQUEUE_CALLBACK_EMPTY) {
+ lkb->lkb_flags &= ~DLM_IFL_NEED_SCHED;
+ spin_unlock(&lkb->lkb_cb_lock);
+ break;
+ }
+ spin_unlock(&lkb->lkb_cb_lock);
}
/* undo kref_get from dlm_add_callback, may cause lkb to be freed */
#include "user.h"
#include "ast.h"
#include "config.h"
+#include "memory.h"
static const char name_prefix[] = "dlm";
static const struct file_operations device_fops;
being removed and then remove that lkb from the orphans list and free it */
void dlm_user_add_ast(struct dlm_lkb *lkb, uint32_t flags, int mode,
- int status, uint32_t sbflags, uint64_t seq)
+ int status, uint32_t sbflags)
{
struct dlm_ls *ls;
struct dlm_user_args *ua;
spin_lock(&proc->asts_spin);
- rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, seq);
- if (rv < 0) {
+ rv = dlm_enqueue_lkb_callback(lkb, flags, mode, status, sbflags);
+ switch (rv) {
+ case DLM_ENQUEUE_CALLBACK_FAILURE:
spin_unlock(&proc->asts_spin);
+ WARN_ON(1);
goto out;
- }
-
- if (list_empty(&lkb->lkb_cb_list)) {
+ case DLM_ENQUEUE_CALLBACK_NEED_SCHED:
kref_get(&lkb->lkb_ref);
list_add_tail(&lkb->lkb_cb_list, &proc->asts);
wake_up_interruptible(&proc->wait);
+ break;
+ case DLM_ENQUEUE_CALLBACK_SUCCESS:
+ break;
+ default:
+ WARN_ON(1);
+ break;
}
spin_unlock(&proc->asts_spin);
struct dlm_user_proc *proc = file->private_data;
struct dlm_lkb *lkb;
DECLARE_WAITQUEUE(wait, current);
- struct dlm_callback cb;
- int rv, resid, copy_lvb = 0;
+ struct dlm_callback *cb;
+ int rv, copy_lvb = 0;
int old_mode, new_mode;
if (count == sizeof(struct dlm_device_version)) {
lkb = list_first_entry(&proc->asts, struct dlm_lkb, lkb_cb_list);
/* rem_lkb_callback sets a new lkb_last_cast */
- old_mode = lkb->lkb_last_cast.mode;
+ old_mode = lkb->lkb_last_cast->mode;
- rv = dlm_rem_lkb_callback(lkb->lkb_resource->res_ls, lkb, &cb, &resid);
- if (rv < 0) {
+ rv = dlm_dequeue_lkb_callback(lkb, &cb);
+ switch (rv) {
+ case DLM_DEQUEUE_CALLBACK_EMPTY:
/* this shouldn't happen; lkb should have been removed from
- list when resid was zero */
+ * list when last item was dequeued
+ */
log_print("dlm_rem_lkb_callback empty %x", lkb->lkb_id);
list_del_init(&lkb->lkb_cb_list);
spin_unlock(&proc->asts_spin);
/* removes ref for proc->asts, may cause lkb to be freed */
dlm_put_lkb(lkb);
+ WARN_ON(1);
goto try_another;
- }
- if (!resid)
+ case DLM_DEQUEUE_CALLBACK_LAST:
list_del_init(&lkb->lkb_cb_list);
- spin_unlock(&proc->asts_spin);
-
- if (cb.flags & DLM_CB_SKIP) {
- /* removes ref for proc->asts, may cause lkb to be freed */
- if (!resid)
- dlm_put_lkb(lkb);
- goto try_another;
+ /* TODO */
+ lkb->lkb_flags &= ~DLM_IFL_NEED_SCHED;
+ break;
+ case DLM_DEQUEUE_CALLBACK_SUCCESS:
+ break;
+ default:
+ WARN_ON(1);
+ break;
}
+ spin_unlock(&proc->asts_spin);
- if (cb.flags & DLM_CB_BAST) {
- trace_dlm_bast(lkb->lkb_resource->res_ls, lkb, cb.mode);
- } else if (cb.flags & DLM_CB_CAST) {
- new_mode = cb.mode;
+ if (cb->flags & DLM_CB_BAST) {
+ trace_dlm_bast(lkb->lkb_resource->res_ls, lkb, cb->mode);
+ } else if (cb->flags & DLM_CB_CAST) {
+ new_mode = cb->mode;
- if (!cb.sb_status && lkb->lkb_lksb->sb_lvbptr &&
+ if (!cb->sb_status && lkb->lkb_lksb->sb_lvbptr &&
dlm_lvb_operations[old_mode + 1][new_mode + 1])
copy_lvb = 1;
- lkb->lkb_lksb->sb_status = cb.sb_status;
- lkb->lkb_lksb->sb_flags = cb.sb_flags;
+ lkb->lkb_lksb->sb_status = cb->sb_status;
+ lkb->lkb_lksb->sb_flags = cb->sb_flags;
trace_dlm_ast(lkb->lkb_resource->res_ls, lkb);
}
rv = copy_result_to_user(lkb->lkb_ua,
test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags),
- cb.flags, cb.mode, copy_lvb, buf, count);
+ cb->flags, cb->mode, copy_lvb, buf, count);
+
+ kref_put(&cb->ref, dlm_release_callback);
/* removes ref for proc->asts, may cause lkb to be freed */
- if (!resid)
+ if (rv == DLM_DEQUEUE_CALLBACK_LAST)
dlm_put_lkb(lkb);
return rv;