diff options
| -rw-r--r-- | fs/dax.c | 130 |
1 files changed, 62 insertions, 68 deletions
@@ -997,11 +997,9 @@ unlock_pte: i_mmap_unlock_read(mapping); } -static int dax_writeback_one(struct dax_device *dax_dev, - struct address_space *mapping, pgoff_t index, void *entry) +static int dax_writeback_one(struct xa_state *xas, struct dax_device *dax_dev, + struct address_space *mapping, void *entry) { - struct radix_tree_root *pages = &mapping->i_pages; - void *entry2, **slot; unsigned long pfn; long ret = 0; size_t size; @@ -1013,29 +1011,35 @@ static int dax_writeback_one(struct dax_device *dax_dev, if (WARN_ON(!xa_is_value(entry))) return -EIO; - xa_lock_irq(pages); - entry2 = get_unlocked_mapping_entry(mapping, index, &slot); - /* Entry got punched out / reallocated? */ - if (!entry2 || WARN_ON_ONCE(!xa_is_value(entry2))) - goto put_unlocked; - /* - * Entry got reallocated elsewhere? No need to writeback. We have to - * compare pfns as we must not bail out due to difference in lockbit - * or entry type. - */ - if (dax_to_pfn(entry2) != dax_to_pfn(entry)) - goto put_unlocked; - if (WARN_ON_ONCE(dax_is_empty_entry(entry) || - dax_is_zero_entry(entry))) { - ret = -EIO; - goto put_unlocked; + if (unlikely(dax_is_locked(entry))) { + void *old_entry = entry; + + entry = get_unlocked_entry(xas); + + /* Entry got punched out / reallocated? */ + if (!entry || WARN_ON_ONCE(!xa_is_value(entry))) + goto put_unlocked; + /* + * Entry got reallocated elsewhere? No need to writeback. + * We have to compare pfns as we must not bail out due to + * difference in lockbit or entry type. + */ + if (dax_to_pfn(old_entry) != dax_to_pfn(entry)) + goto put_unlocked; + if (WARN_ON_ONCE(dax_is_empty_entry(entry) || + dax_is_zero_entry(entry))) { + ret = -EIO; + goto put_unlocked; + } + + /* Another fsync thread may have already done this entry */ + if (!xas_get_mark(xas, PAGECACHE_TAG_TOWRITE)) + goto put_unlocked; } - /* Another fsync thread may have already written back this entry */ - if (!radix_tree_tag_get(pages, index, PAGECACHE_TAG_TOWRITE)) - goto put_unlocked; /* Lock the entry to serialize with page faults */ - entry = lock_slot(mapping, slot); + dax_lock_entry(xas, entry); + /* * We can clear the tag now but we have to be careful so that concurrent * dax_writeback_one() calls for the same index cannot finish before we @@ -1043,8 +1047,8 @@ static int dax_writeback_one(struct dax_device *dax_dev, * at the entry only under the i_pages lock and once they do that * they will see the entry locked and wait for it to unlock. */ - radix_tree_tag_clear(pages, index, PAGECACHE_TAG_TOWRITE); - xa_unlock_irq(pages); + xas_clear_mark(xas, PAGECACHE_TAG_TOWRITE); + xas_unlock_irq(xas); /* * Even if dax_writeback_mapping_range() was given a wbc->range_start @@ -1056,7 +1060,7 @@ static int dax_writeback_one(struct dax_device *dax_dev, pfn = dax_to_pfn(entry); size = PAGE_SIZE << dax_entry_order(entry); - dax_entry_mkclean(mapping, index, pfn); + dax_entry_mkclean(mapping, xas->xa_index, pfn); dax_flush(dax_dev, page_address(pfn_to_page(pfn)), size); /* * After we have flushed the cache, we can clear the dirty tag. There @@ -1064,16 +1068,18 @@ static int dax_writeback_one(struct dax_device *dax_dev, * the pfn mappings are writeprotected and fault waits for mapping * entry lock. */ - xa_lock_irq(pages); - radix_tree_tag_clear(pages, index, PAGECACHE_TAG_DIRTY); - xa_unlock_irq(pages); - trace_dax_writeback_one(mapping->host, index, size >> PAGE_SHIFT); - put_locked_mapping_entry(mapping, index); + xas_reset(xas); + xas_lock_irq(xas); + xas_store(xas, entry); + xas_clear_mark(xas, PAGECACHE_TAG_DIRTY); + dax_wake_entry(xas, entry, false); + + trace_dax_writeback_one(mapping->host, xas->xa_index, + size >> PAGE_SHIFT); return ret; put_unlocked: - put_unlocked_mapping_entry(mapping, index, entry2); - xa_unlock_irq(pages); + put_unlocked_entry(xas, entry); return ret; } @@ -1085,13 +1091,13 @@ static int dax_writeback_one(struct dax_device *dax_dev, int dax_writeback_mapping_range(struct address_space *mapping, struct block_device *bdev, struct writeback_control *wbc) { + XA_STATE(xas, &mapping->i_pages, wbc->range_start >> PAGE_SHIFT); struct inode *inode = mapping->host; - pgoff_t start_index, end_index; - pgoff_t indices[PAGEVEC_SIZE]; + pgoff_t end_index = wbc->range_end >> PAGE_SHIFT; struct dax_device *dax_dev; - struct pagevec pvec; - bool done = false; - int i, ret = 0; + void *entry; + int ret = 0; + unsigned int scanned = 0; if (WARN_ON_ONCE(inode->i_blkbits != PAGE_SHIFT)) return -EIO; @@ -1103,41 +1109,29 @@ int dax_writeback_mapping_range(struct address_space *mapping, if (!dax_dev) return -EIO; - start_index = wbc->range_start >> PAGE_SHIFT; - end_index = wbc->range_end >> PAGE_SHIFT; - - trace_dax_writeback_range(inode, start_index, end_index); - - tag_pages_for_writeback(mapping, start_index, end_index); + trace_dax_writeback_range(inode, xas.xa_index, end_index); - pagevec_init(&pvec); - while (!done) { - pvec.nr = find_get_entries_tag(mapping, start_index, - PAGECACHE_TAG_TOWRITE, PAGEVEC_SIZE, - pvec.pages, indices); + tag_pages_for_writeback(mapping, xas.xa_index, end_index); - if (pvec.nr == 0) + xas_lock_irq(&xas); + xas_for_each_marked(&xas, entry, end_index, PAGECACHE_TAG_TOWRITE) { + ret = dax_writeback_one(&xas, dax_dev, mapping, entry); + if (ret < 0) { + mapping_set_error(mapping, ret); break; - - for (i = 0; i < pvec.nr; i++) { - if (indices[i] > end_index) { - done = true; - break; - } - - ret = dax_writeback_one(dax_dev, mapping, indices[i], - pvec.pages[i]); - if (ret < 0) { - mapping_set_error(mapping, ret); - goto out; - } } - start_index = indices[pvec.nr - 1] + 1; + if (++scanned % XA_CHECK_SCHED) + continue; + + xas_pause(&xas); + xas_unlock_irq(&xas); + cond_resched(); + xas_lock_irq(&xas); } -out: + xas_unlock_irq(&xas); put_dax(dax_dev); - trace_dax_writeback_range_done(inode, start_index, end_index); - return (ret < 0 ? ret : 0); + trace_dax_writeback_range_done(inode, xas.xa_index, end_index); + return ret; } EXPORT_SYMBOL_GPL(dax_writeback_mapping_range); |