/**
* Internal version of cl_page_top, it should be called with page referenced,
- * or coh_page_guard held.
+ * or cp_lock held.
*/
static struct cl_page *cl_page_top_trusted(struct cl_page *page)
{
const struct cl_page_slice *slice;
#ifdef INVARIANT_CHECK
- struct cl_object_header *ch = cl_object_header(page->cp_obj);
-
if (!cfs_atomic_read(&page->cp_ref))
- LASSERT_SPIN_LOCKED(&ch->coh_page_guard);
+ LASSERT_SPIN_LOCKED(&page->cp_lock);
#endif
ENTRY;
"cl_page", page);
page->cp_index = ind;
cl_page_state_set_trust(page, CPS_CACHED);
+ cfs_spin_lock_init(&page->cp_lock);
page->cp_type = type;
CFS_INIT_LIST_HEAD(&page->cp_layers);
CFS_INIT_LIST_HEAD(&page->cp_batch);
idx, PFID(&hdr->coh_lu.loh_fid), vmpage, vmpage->private, type);
/* fast path. */
if (type == CPT_CACHEABLE) {
+ /* cl_page::cp_lock is used to protect the page state and
+ * refcount, but need an external lock to protect the
+ * child/parent relationship, so vmpage lock must be held for
+ * this purpose. */
+ KLASSERT(PageLocked(vmpage));
/*
* cl_vmpage_page() can be called here without any locks as
*
*/
void cl_page_put(const struct lu_env *env, struct cl_page *page)
{
- struct cl_object_header *hdr;
struct cl_site *site = cl_object_site(page->cp_obj);
PASSERT(env, page, cfs_atomic_read(&page->cp_ref) > !!page->cp_parent);
CL_PAGE_HEADER(D_TRACE, env, page, "%d\n",
cfs_atomic_read(&page->cp_ref));
- hdr = cl_object_header(cl_object_top(page->cp_obj));
- if (cfs_atomic_dec_and_lock(&page->cp_ref, &hdr->coh_page_guard)) {
+ if (cfs_atomic_dec_and_lock(&page->cp_ref, &page->cp_lock)) {
cfs_atomic_dec(&site->cs_pages.cs_busy);
/* We're going to access the page w/o a reference, but it's
- * ok because we have grabbed the lock coh_page_guard, which
+ * ok because we have grabbed the lock cp_lock, which
* means nobody is able to free this page behind us.
*/
if (page->cp_state == CPS_FREEING) {
/* We drop the page reference and check the page state
- * inside the coh_page_guard. So that if it gets here,
+ * inside the cp_lock. So that if it gets here,
* it is the REALLY last reference to this page.
*/
- cfs_spin_unlock(&hdr->coh_page_guard);
+ cfs_spin_unlock(&page->cp_lock);
LASSERT(cfs_atomic_read(&page->cp_ref) == 0);
PASSERT(env, page, page->cp_owner == NULL);
EXIT;
return;
}
- cfs_spin_unlock(&hdr->coh_page_guard);
+ cfs_spin_unlock(&page->cp_lock);
}
EXIT;
*/
struct cl_page *cl_vmpage_page(cfs_page_t *vmpage, struct cl_object *obj)
{
- struct cl_page *page;
- struct cl_object_header *hdr;
+ struct cl_page *top;
+ struct cl_page *page;
ENTRY;
KLASSERT(PageLocked(vmpage));
* This loop assumes that ->private points to the top-most page. This
* can be rectified easily.
*/
- hdr = cl_object_header(cl_object_top(obj));
- cfs_spin_lock(&hdr->coh_page_guard);
- for (page = (void *)vmpage->private;
- page != NULL; page = page->cp_child) {
+ top = (struct cl_page *)vmpage->private;
+ if (top == NULL)
+ RETURN(NULL);
+
+ cfs_spin_lock(&top->cp_lock);
+ for (page = top; page != NULL; page = page->cp_child) {
if (cl_object_same(page->cp_obj, obj)) {
cl_page_get_trust(page);
break;
}
}
- cfs_spin_unlock(&hdr->coh_page_guard);
+ cfs_spin_unlock(&top->cp_lock);
LASSERT(ergo(page, page->cp_type == CPT_CACHEABLE));
RETURN(page);
}