struct exceptional_entry_key key;
};
+/**
+ * enum dax_wake_mode: waitqueue wakeup behaviour
+ * @WAKE_ALL: wake all waiters in the waitqueue
+ * @WAKE_NEXT: wake only the first waiter in the waitqueue
+ */
+enum dax_wake_mode {
+ WAKE_ALL,
+ WAKE_NEXT,
+};
+
static wait_queue_head_t *dax_entry_waitqueue(struct xa_state *xas,
void *entry, struct exceptional_entry_key *key)
{
* The important information it's conveying is whether the entry at
* this index used to be a PMD entry.
*/
-static void dax_wake_entry(struct xa_state *xas, void *entry, bool wake_all)
+static void dax_wake_entry(struct xa_state *xas, void *entry,
+ enum dax_wake_mode mode)
{
struct exceptional_entry_key key;
wait_queue_head_t *wq;
* must be in the waitqueue and the following check will see them.
*/
if (waitqueue_active(wq))
- __wake_up(wq, TASK_NORMAL, wake_all ? 0 : 1, &key);
+ __wake_up(wq, TASK_NORMAL, mode == WAKE_ALL ? 0 : 1, &key);
}
/*
finish_wait(wq, &ewait.wait);
}
-static void put_unlocked_entry(struct xa_state *xas, void *entry)
+static void put_unlocked_entry(struct xa_state *xas, void *entry,
+ enum dax_wake_mode mode)
{
- /* If we were the only waiter woken, wake the next one */
if (entry && !dax_is_conflict(entry))
- dax_wake_entry(xas, entry, false);
+ dax_wake_entry(xas, entry, mode);
}
/*
old = xas_store(xas, entry);
xas_unlock_irq(xas);
BUG_ON(!dax_is_locked(old));
- dax_wake_entry(xas, entry, false);
+ dax_wake_entry(xas, entry, WAKE_NEXT);
}
/*
struct address_space *mapping, unsigned int order)
{
unsigned long index = xas->xa_index;
- bool pmd_downgrade = false; /* splitting PMD entry into PTE entries? */
+ bool pmd_downgrade; /* splitting PMD entry into PTE entries? */
void *entry;
retry:
+ pmd_downgrade = false;
xas_lock_irq(xas);
entry = get_unlocked_entry(xas, order);
dax_disassociate_entry(entry, mapping, false);
xas_store(xas, NULL); /* undo the PMD join */
- dax_wake_entry(xas, entry, true);
+ dax_wake_entry(xas, entry, WAKE_ALL);
mapping->nrexceptional--;
entry = NULL;
xas_set(xas, index);
}
/**
- * dax_layout_busy_page - find first pinned page in @mapping
+ * dax_layout_busy_page_range - find first pinned page in @mapping
* @mapping: address space to scan for a page with ref count > 1
+ * @start: Starting offset. Page containing 'start' is included.
+ * @end: End offset. Page containing 'end' is included. If 'end' is LLONG_MAX,
+ * pages from 'start' till the end of file are included.
*
* DAX requires ZONE_DEVICE mapped pages. These pages are never
* 'onlined' to the page allocator so they are considered idle when
* to be able to run unmap_mapping_range() and subsequently not race
* mapping_mapped() becoming true.
*/
-struct page *dax_layout_busy_page(struct address_space *mapping)
+struct page *dax_layout_busy_page_range(struct address_space *mapping,
+ loff_t start, loff_t end)
{
- XA_STATE(xas, &mapping->i_pages, 0);
void *entry;
unsigned int scanned = 0;
struct page *page = NULL;
+ pgoff_t start_idx = start >> PAGE_SHIFT;
+ pgoff_t end_idx;
+ XA_STATE(xas, &mapping->i_pages, start_idx);
/*
* In the 'limited' case get_user_pages() for dax is disabled.
if (!dax_mapping(mapping) || !mapping_mapped(mapping))
return NULL;
+ /* If end == LLONG_MAX, all pages from start to till end of file */
+ if (end == LLONG_MAX)
+ end_idx = ULONG_MAX;
+ else
+ end_idx = end >> PAGE_SHIFT;
/*
* If we race get_user_pages_fast() here either we'll see the
* elevated page count in the iteration and wait, or
* against is no longer mapped in the page tables and bail to the
* get_user_pages() slow path. The slow path is protected by
* pte_lock() and pmd_lock(). New references are not taken without
- * holding those locks, and unmap_mapping_range() will not zero the
+ * holding those locks, and unmap_mapping_pages() will not zero the
* pte or pmd without holding the respective lock, so we are
* guaranteed to either see new references or prevent new
* references from being established.
*/
- unmap_mapping_range(mapping, 0, 0, 0);
+ unmap_mapping_pages(mapping, start_idx, end_idx - start_idx + 1, 0);
xas_lock_irq(&xas);
- xas_for_each(&xas, entry, ULONG_MAX) {
+ xas_for_each(&xas, entry, end_idx) {
if (WARN_ON_ONCE(!xa_is_value(entry)))
continue;
if (unlikely(dax_is_locked(entry)))
entry = get_unlocked_entry(&xas, 0);
if (entry)
page = dax_busy_page(entry);
- put_unlocked_entry(&xas, entry);
+ put_unlocked_entry(&xas, entry, WAKE_NEXT);
if (page)
break;
if (++scanned % XA_CHECK_SCHED)
xas_unlock_irq(&xas);
return page;
}
+EXPORT_SYMBOL_GPL(dax_layout_busy_page_range);
+
+struct page *dax_layout_busy_page(struct address_space *mapping)
+{
+ return dax_layout_busy_page_range(mapping, 0, LLONG_MAX);
+}
EXPORT_SYMBOL_GPL(dax_layout_busy_page);
static int __dax_invalidate_entry(struct address_space *mapping,
mapping->nrexceptional--;
ret = 1;
out:
- put_unlocked_entry(&xas, entry);
+ put_unlocked_entry(&xas, entry, WAKE_ALL);
xas_unlock_irq(&xas);
return ret;
}
address = pgoff_address(index, vma);
/*
- * Note because we provide range to follow_pte_pmd it will
- * call mmu_notifier_invalidate_range_start() on our behalf
- * before taking any lock.
+ * follow_invalidate_pte() will use the range to call
+ * mmu_notifier_invalidate_range_start() on our behalf before
+ * taking any lock.
*/
- if (follow_pte_pmd(vma->vm_mm, address, &range,
- &ptep, &pmdp, &ptl))
+ if (follow_invalidate_pte(vma->vm_mm, address, &range, &ptep,
+ &pmdp, &ptl))
continue;
/*
xas_lock_irq(xas);
xas_store(xas, entry);
xas_clear_mark(xas, PAGECACHE_TAG_DIRTY);
- dax_wake_entry(xas, entry, false);
+ dax_wake_entry(xas, entry, WAKE_NEXT);
trace_dax_writeback_one(mapping->host, index, count);
return ret;
put_unlocked:
- put_unlocked_entry(xas, entry);
+ put_unlocked_entry(xas, entry, WAKE_NEXT);
return ret;
}
return ret;
}
-int dax_iomap_zero(loff_t pos, unsigned offset, unsigned size,
- struct iomap *iomap)
+s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
{
sector_t sector = iomap_sector(iomap, pos & PAGE_MASK);
pgoff_t pgoff;
long rc, id;
void *kaddr;
bool page_aligned = false;
-
+ unsigned offset = offset_in_page(pos);
+ unsigned size = min_t(u64, PAGE_SIZE - offset, length);
if (IS_ALIGNED(sector << SECTOR_SHIFT, PAGE_SIZE) &&
- IS_ALIGNED(size, PAGE_SIZE))
+ (size == PAGE_SIZE))
page_aligned = true;
rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff);
id = dax_read_lock();
if (page_aligned)
- rc = dax_zero_page_range(iomap->dax_dev, pgoff,
- size >> PAGE_SHIFT);
+ rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1);
else
rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL);
if (rc < 0) {
dax_flush(iomap->dax_dev, kaddr + offset, size);
}
dax_read_unlock(id);
- return 0;
+ return size;
}
static loff_t
/* Did we race with someone splitting entry or so? */
if (!entry || dax_is_conflict(entry) ||
(order == 0 && !dax_is_pte_entry(entry))) {
- put_unlocked_entry(&xas, entry);
+ put_unlocked_entry(&xas, entry, WAKE_NEXT);
xas_unlock_irq(&xas);
trace_dax_insert_pfn_mkwrite_no_entry(mapping->host, vmf,
VM_FAULT_NOPAGE);
projects / platform / kernel / linux-rpi.git / blobdiff