* Contains functions related to writing back dirty pages at the
* address_space level.
*
- * 10Apr2002 akpm@zip.com.au
+ * 10Apr2002 Andrew Morton
* Initial version
*/
int dirty_background_ratio = 5;
/*
+ * free highmem will not be subtracted from the total free memory
+ * for calculating free ratios if vm_highmem_is_dirtyable is true
+ */
+int vm_highmem_is_dirtyable;
+
+/*
* The generator of dirty data starts writeback at this percentage
*/
int vm_dirty_ratio = 10;
static struct prop_descriptor vm_completions;
static struct prop_descriptor vm_dirties;
-static unsigned long determine_dirtyable_memory(void);
-
/*
* couple the period to the dirty_ratio:
*
*/
static inline void __bdi_writeout_inc(struct backing_dev_info *bdi)
{
- __prop_inc_percpu(&vm_completions, &bdi->completions);
+ __prop_inc_percpu_max(&vm_completions, &bdi->completions,
+ bdi->max_prop_frac);
}
+void bdi_writeout_inc(struct backing_dev_info *bdi)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __bdi_writeout_inc(bdi);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(bdi_writeout_inc);
+
static inline void task_dirty_inc(struct task_struct *tsk)
{
prop_inc_single(&vm_dirties, &tsk->dirties);
avail_dirty = dirty -
(global_page_state(NR_FILE_DIRTY) +
global_page_state(NR_WRITEBACK) +
- global_page_state(NR_UNSTABLE_NFS));
+ global_page_state(NR_UNSTABLE_NFS) +
+ global_page_state(NR_WRITEBACK_TEMP));
if (avail_dirty < 0)
avail_dirty = 0;
*
* dirty -= (dirty/8) * p_{t}
*/
-void task_dirty_limit(struct task_struct *tsk, long *pdirty)
+static void task_dirty_limit(struct task_struct *tsk, long *pdirty)
{
long numerator, denominator;
long dirty = *pdirty;
}
/*
+ *
+ */
+static DEFINE_SPINLOCK(bdi_lock);
+static unsigned int bdi_min_ratio;
+
+int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio)
+{
+ int ret = 0;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bdi_lock, flags);
+ if (min_ratio > bdi->max_ratio) {
+ ret = -EINVAL;
+ } else {
+ min_ratio -= bdi->min_ratio;
+ if (bdi_min_ratio + min_ratio < 100) {
+ bdi_min_ratio += min_ratio;
+ bdi->min_ratio += min_ratio;
+ } else {
+ ret = -EINVAL;
+ }
+ }
+ spin_unlock_irqrestore(&bdi_lock, flags);
+
+ return ret;
+}
+
+int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned max_ratio)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ if (max_ratio > 100)
+ return -EINVAL;
+
+ spin_lock_irqsave(&bdi_lock, flags);
+ if (bdi->min_ratio > max_ratio) {
+ ret = -EINVAL;
+ } else {
+ bdi->max_ratio = max_ratio;
+ bdi->max_prop_frac = (PROP_FRAC_BASE * max_ratio) / 100;
+ }
+ spin_unlock_irqrestore(&bdi_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(bdi_set_max_ratio);
+
+/*
* Work out the current dirty-memory clamping and background writeout
* thresholds.
*
struct zone *z =
&NODE_DATA(node)->node_zones[ZONE_HIGHMEM];
- x += zone_page_state(z, NR_FREE_PAGES)
- + zone_page_state(z, NR_INACTIVE)
- + zone_page_state(z, NR_ACTIVE);
+ x += zone_page_state(z, NR_FREE_PAGES) + zone_lru_pages(z);
}
/*
* Make sure that the number of highmem pages is never larger
#endif
}
-static unsigned long determine_dirtyable_memory(void)
+/**
+ * determine_dirtyable_memory - amount of memory that may be used
+ *
+ * Returns the numebr of pages that can currently be freed and used
+ * by the kernel for direct mappings.
+ */
+unsigned long determine_dirtyable_memory(void)
{
unsigned long x;
- x = global_page_state(NR_FREE_PAGES)
- + global_page_state(NR_INACTIVE)
- + global_page_state(NR_ACTIVE);
- x -= highmem_dirtyable_memory(x);
+ x = global_page_state(NR_FREE_PAGES) + global_lru_pages();
+
+ if (!vm_highmem_is_dirtyable)
+ x -= highmem_dirtyable_memory(x);
+
return x + 1; /* Ensure that we never return 0 */
}
-static void
+void
get_dirty_limits(long *pbackground, long *pdirty, long *pbdi_dirty,
struct backing_dev_info *bdi)
{
int background_ratio; /* Percentages */
int dirty_ratio;
- int unmapped_ratio;
long background;
long dirty;
unsigned long available_memory = determine_dirtyable_memory();
struct task_struct *tsk;
- unmapped_ratio = 100 - ((global_page_state(NR_FILE_MAPPED) +
- global_page_state(NR_ANON_PAGES)) * 100) /
- available_memory;
-
dirty_ratio = vm_dirty_ratio;
- if (dirty_ratio > unmapped_ratio / 2)
- dirty_ratio = unmapped_ratio / 2;
-
if (dirty_ratio < 5)
dirty_ratio = 5;
*pdirty = dirty;
if (bdi) {
- u64 bdi_dirty = dirty;
+ u64 bdi_dirty;
long numerator, denominator;
/*
*/
bdi_writeout_fraction(bdi, &numerator, &denominator);
+ bdi_dirty = (dirty * (100 - bdi_min_ratio)) / 100;
bdi_dirty *= numerator;
do_div(bdi_dirty, denominator);
+ bdi_dirty += (dirty * bdi->min_ratio) / 100;
+ if (bdi_dirty > (dirty * bdi->max_ratio) / 100)
+ bdi_dirty = dirty * bdi->max_ratio / 100;
*pbdi_dirty = bdi_dirty;
clip_bdi_dirty_limit(bdi, dirty, pbdi_dirty);
pgoff_t end; /* Inclusive */
int scanned = 0;
int range_whole = 0;
+ long nr_to_write = wbc->nr_to_write;
if (wbc->nonblocking && bdi_write_congested(bdi)) {
wbc->encountered_congestion = 1;
unlock_page(page);
ret = 0;
}
- if (ret || (--(wbc->nr_to_write) <= 0))
+ if (ret || (--nr_to_write <= 0))
done = 1;
if (wbc->nonblocking && bdi_write_congested(bdi)) {
wbc->encountered_congestion = 1;
index = 0;
goto retry;
}
- if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
- mapping->writeback_index = index;
+ if (!wbc->no_nrwrite_index_update) {
+ if (wbc->range_cyclic || (range_whole && nr_to_write > 0))
+ mapping->writeback_index = index;
+ wbc->nr_to_write = nr_to_write;
+ }
+
return ret;
}
EXPORT_SYMBOL(write_cache_pages);
if (!mapping)
return 1;
- write_lock_irq(&mapping->tree_lock);
+ spin_lock_irq(&mapping->tree_lock);
mapping2 = page_mapping(page);
if (mapping2) { /* Race with truncate? */
BUG_ON(mapping2 != mapping);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
- write_unlock_irq(&mapping->tree_lock);
+ spin_unlock_irq(&mapping->tree_lock);
if (mapping->host) {
/* !PageAnon && !swapper_space */
__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
return 0;
}
-int fastcall set_page_dirty(struct page *page)
+int set_page_dirty(struct page *page)
{
int ret = __set_page_dirty(page);
if (ret)
struct backing_dev_info *bdi = mapping->backing_dev_info;
unsigned long flags;
- write_lock_irqsave(&mapping->tree_lock, flags);
+ spin_lock_irqsave(&mapping->tree_lock, flags);
ret = TestClearPageWriteback(page);
if (ret) {
radix_tree_tag_clear(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_WRITEBACK);
- if (bdi_cap_writeback_dirty(bdi)) {
+ if (bdi_cap_account_writeback(bdi)) {
__dec_bdi_stat(bdi, BDI_WRITEBACK);
__bdi_writeout_inc(bdi);
}
}
- write_unlock_irqrestore(&mapping->tree_lock, flags);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
} else {
ret = TestClearPageWriteback(page);
}
struct backing_dev_info *bdi = mapping->backing_dev_info;
unsigned long flags;
- write_lock_irqsave(&mapping->tree_lock, flags);
+ spin_lock_irqsave(&mapping->tree_lock, flags);
ret = TestSetPageWriteback(page);
if (!ret) {
radix_tree_tag_set(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_WRITEBACK);
- if (bdi_cap_writeback_dirty(bdi))
+ if (bdi_cap_account_writeback(bdi))
__inc_bdi_stat(bdi, BDI_WRITEBACK);
}
if (!PageDirty(page))
radix_tree_tag_clear(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_DIRTY);
- write_unlock_irqrestore(&mapping->tree_lock, flags);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
} else {
ret = TestSetPageWriteback(page);
}