On Mon, Jun 01, 2015 at 08:52:49PM +0530, Chandan Rajendra wrote: > In subpagesize-blocksize scenario a page can have more than one block. So > in addition to PagePrivate2 flag, we would have to track the I/O status of > each block of a page to reliably mark the ordered extent as complete. > > Signed-off-by: Chandan Rajendra <chan...@linux.vnet.ibm.com> > --- > fs/btrfs/extent_io.c | 19 +-- > fs/btrfs/extent_io.h | 5 +- > fs/btrfs/inode.c | 346 > +++++++++++++++++++++++++++++++++++------------- > fs/btrfs/ordered-data.c | 17 +++ > fs/btrfs/ordered-data.h | 4 + > 5 files changed, 287 insertions(+), 104 deletions(-) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index 0110abc..55f900a 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -4545,11 +4545,10 @@ int extent_invalidatepage(struct extent_io_tree *tree, > * to drop the page. > */ > static int try_release_extent_state(struct extent_map_tree *map, > - struct extent_io_tree *tree, > - struct page *page, gfp_t mask) > + struct extent_io_tree *tree, > + struct page *page, u64 start, u64 end, > + gfp_t mask) > { > - u64 start = page_offset(page); > - u64 end = start + PAGE_CACHE_SIZE - 1; > int ret = 1; > > if (test_range_bit(tree, start, end, > @@ -4583,12 +4582,12 @@ static int try_release_extent_state(struct > extent_map_tree *map, > * map records are removed > */ > int try_release_extent_mapping(struct extent_map_tree *map, > - struct extent_io_tree *tree, struct page *page, > - gfp_t mask) > + struct extent_io_tree *tree, struct page *page, > + u64 start, u64 end, gfp_t mask) > { > struct extent_map *em; > - u64 start = page_offset(page); > - u64 end = start + PAGE_CACHE_SIZE - 1; > + u64 orig_start = start; > + u64 orig_end = end; > > if ((mask & __GFP_WAIT) && > page->mapping->host->i_size > 16 * 1024 * 1024) { > @@ -4622,7 +4621,9 @@ int try_release_extent_mapping(struct extent_map_tree > *map, > free_extent_map(em); > } > } > - return try_release_extent_state(map, tree, page, mask); > + return try_release_extent_state(map, tree, page, > + orig_start, orig_end, > + mask); > } > > /* > diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h > index 8fe5ac3..c629e53 100644 > --- a/fs/btrfs/extent_io.h > +++ b/fs/btrfs/extent_io.h > @@ -217,8 +217,9 @@ typedef struct extent_map *(get_extent_t)(struct inode > *inode, > void extent_io_tree_init(struct extent_io_tree *tree, > struct address_space *mapping); > int try_release_extent_mapping(struct extent_map_tree *map, > - struct extent_io_tree *tree, struct page *page, > - gfp_t mask); > + struct extent_io_tree *tree, struct page *page, > + u64 start, u64 end, > + gfp_t mask); > int try_release_extent_buffer(struct page *page); > int lock_extent(struct extent_io_tree *tree, u64 start, u64 end); > int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index bff60c6..bfffc62 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -2990,56 +2990,115 @@ static void finish_ordered_fn(struct btrfs_work > *work) > btrfs_finish_ordered_io(ordered_extent); > } > > -static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, > - struct extent_state *state, int uptodate) > +static void mark_blks_io_complete(struct btrfs_ordered_extent *ordered, > + u64 blk, u64 nr_blks, int uptodate) > { > - struct inode *inode = page->mapping->host; > + struct inode *inode = ordered->inode; > struct btrfs_root *root = BTRFS_I(inode)->root; > - struct btrfs_ordered_extent *ordered_extent = NULL; > struct btrfs_workqueue *wq; > btrfs_work_func_t func; > - u64 ordered_start, ordered_end; > int done; > > - trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); > + while (nr_blks--) { > + if (test_and_set_bit(blk, ordered->blocks_done)) { > + blk++; > + continue; > + } > > - ClearPagePrivate2(page); > -loop: > - ordered_extent = btrfs_lookup_ordered_range(inode, start, > - end - start + 1); > - if (!ordered_extent) > - goto out; > + done = btrfs_dec_test_ordered_pending(inode, &ordered, > + ordered->file_offset > + + (blk << > inode->i_sb->s_blocksize_bits), > + root->sectorsize, > + uptodate); > + if (done) { > + if (btrfs_is_free_space_inode(inode)) { > + wq = root->fs_info->endio_freespace_worker; > + func = btrfs_freespace_write_helper; > + } else { > + wq = root->fs_info->endio_write_workers; > + func = btrfs_endio_write_helper; > + } > > - ordered_start = max_t(u64, start, ordered_extent->file_offset); > - ordered_end = min_t(u64, end, > - ordered_extent->file_offset + ordered_extent->len - 1); > - > - done = btrfs_dec_test_ordered_pending(inode, &ordered_extent, > - ordered_start, > - ordered_end - ordered_start + 1, > - uptodate); > - if (done) { > - if (btrfs_is_free_space_inode(inode)) { > - wq = root->fs_info->endio_freespace_worker; > - func = btrfs_freespace_write_helper; > - } else { > - wq = root->fs_info->endio_write_workers; > - func = btrfs_endio_write_helper; > + btrfs_init_work(&ordered->work, func, > + finish_ordered_fn, NULL, NULL); > + btrfs_queue_work(wq, &ordered->work); > } > > - btrfs_init_work(&ordered_extent->work, func, > - finish_ordered_fn, NULL, NULL); > - btrfs_queue_work(wq, &ordered_extent->work); > + blk++; > } > +} > > - btrfs_put_ordered_extent(ordered_extent); > +int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, > + struct extent_state *state, int uptodate) > +{ > + struct inode *inode = page->mapping->host; > + struct btrfs_root *root = BTRFS_I(inode)->root; > + struct btrfs_ordered_extent *ordered_extent = NULL; > + u64 blk, nr_blks; > + int clear; > > - start = ordered_end + 1; > + trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); > > - if (start < end) > - goto loop; > + while (start < end) { > + ordered_extent = btrfs_lookup_ordered_extent(inode, start); > + if (!ordered_extent) { > + start += root->sectorsize; > + continue; > + } > + > + blk = (start - ordered_extent->file_offset) > + >> inode->i_sb->s_blocksize_bits; > + > + nr_blks = (min(end, ordered_extent->file_offset + > ordered_extent->len - 1) > + + 1 - start) >> inode->i_sb->s_blocksize_bits; > + > + BUG_ON(!nr_blks); > + > + mark_blks_io_complete(ordered_extent, blk, nr_blks, uptodate);
Range [start, end] is surely contiguous, so why are we processing blocks one by one in mark_blks_io_complete()? Same question for invalidatepage(). Thanks, -liubo > + > + start = ordered_extent->file_offset + ordered_extent->len; > + > + btrfs_put_ordered_extent(ordered_extent); > + } > + > + start = page_offset(page); > + end = start + PAGE_CACHE_SIZE - 1; > + clear = 1; > + > + while (start < end) { > + ordered_extent = btrfs_lookup_ordered_extent(inode, start); > + if (!ordered_extent) { > + start += root->sectorsize; > + continue; > + } > + > + blk = (start - ordered_extent->file_offset) > + >> inode->i_sb->s_blocksize_bits; > + nr_blks = (min(end, ordered_extent->file_offset + > ordered_extent->len - 1) > + + 1 - start) >> inode->i_sb->s_blocksize_bits; > + > + BUG_ON(!nr_blks); > + > + while (nr_blks--) { > + if (!test_bit(blk++, ordered_extent->blocks_done)) { > + clear = 0; > + break; > + } > + } > + > + if (!clear) { > + btrfs_put_ordered_extent(ordered_extent); > + break; > + } > + > + start += ordered_extent->len; > + > + btrfs_put_ordered_extent(ordered_extent); > + } > + > + if (clear) > + ClearPagePrivate2(page); > > -out: > return 0; > } > > @@ -8472,7 +8531,9 @@ btrfs_readpages(struct file *file, struct address_space > *mapping, > return extent_readpages(tree, mapping, pages, nr_pages, > btrfs_get_extent); > } > -static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) > + > +static int __btrfs_releasepage(struct page *page, u64 start, u64 end, > + gfp_t gfp_flags) > { > struct extent_io_tree *tree; > struct extent_map_tree *map; > @@ -8480,31 +8541,149 @@ static int __btrfs_releasepage(struct page *page, > gfp_t gfp_flags) > > tree = &BTRFS_I(page->mapping->host)->io_tree; > map = &BTRFS_I(page->mapping->host)->extent_tree; > - ret = try_release_extent_mapping(map, tree, page, gfp_flags); > - if (ret == 1) > + > + ret = try_release_extent_mapping(map, tree, page, start, end, > + gfp_flags); > + if ((ret == 1) && ((end - start + 1) == PAGE_CACHE_SIZE)) { > clear_page_extent_mapped(page); > + } else { > + ret = 0; > + } > > return ret; > } > > static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) > { > + u64 start = page_offset(page); > + u64 end = start + PAGE_CACHE_SIZE - 1; > + > if (PageWriteback(page) || PageDirty(page)) > return 0; > - return __btrfs_releasepage(page, gfp_flags & GFP_NOFS); > + > + return __btrfs_releasepage(page, start, end, gfp_flags & GFP_NOFS); > +} > + > +static void invalidate_ordered_extent_blocks(struct inode *inode, > + struct btrfs_ordered_extent *ordered, > + u64 locked_start, u64 locked_end, > + u64 cur, > + int inode_evicting) > +{ > + struct btrfs_root *root = BTRFS_I(inode)->root; > + struct btrfs_ordered_inode_tree *ordered_tree; > + struct extent_io_tree *tree; > + u64 blk, blk_done, nr_blks; > + u64 end; > + u64 new_len; > + > + tree = &BTRFS_I(inode)->io_tree; > + > + end = min(locked_end, ordered->file_offset + ordered->len - 1); > + > + if (!inode_evicting) { > + clear_extent_bit(tree, cur, end, > + EXTENT_DIRTY | EXTENT_DELALLOC | > + EXTENT_DO_ACCOUNTING | > + EXTENT_DEFRAG, 1, 0, NULL, > + GFP_NOFS); > + unlock_extent(tree, locked_start, locked_end); > + } > + > + > + ordered_tree = &BTRFS_I(inode)->ordered_tree; > + spin_lock_irq(&ordered_tree->lock); > + set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); > + new_len = cur - ordered->file_offset; > + if (new_len < ordered->truncated_len) > + ordered->truncated_len = new_len; > + > + blk = (cur - ordered->file_offset) >> inode->i_sb->s_blocksize_bits; > + nr_blks = (end + 1 - cur) >> inode->i_sb->s_blocksize_bits; > + > + while (nr_blks--) { > + blk_done = !test_and_set_bit(blk, ordered->blocks_done); > + if (blk_done) { > + spin_unlock_irq(&ordered_tree->lock); > + if (btrfs_dec_test_ordered_pending(inode, &ordered, > + > ordered->file_offset + (blk << inode->i_sb->s_blocksize_bits), > + > root->sectorsize, > + 1)) > + btrfs_finish_ordered_io(ordered); > + > + spin_lock_irq(&ordered_tree->lock); > + } > + blk++; > + } > + > + spin_unlock_irq(&ordered_tree->lock); > + > + if (!inode_evicting) > + lock_extent_bits(tree, locked_start, locked_end, 0, NULL); > +} > + > +static int page_blocks_written(struct page *page) > +{ > + struct btrfs_ordered_extent *ordered; > + struct btrfs_root *root; > + struct inode *inode; > + unsigned long outstanding_blk; > + u64 page_start, page_end; > + u64 blk, last_blk, nr_blks; > + u64 cur; > + u64 len; > + > + inode = page->mapping->host; > + root = BTRFS_I(inode)->root; > + > + page_start = page_offset(page); > + page_end = page_start + PAGE_CACHE_SIZE - 1; > + > + cur = page_start; > + while (cur < page_end) { > + ordered = btrfs_lookup_ordered_extent(inode, cur); > + if (!ordered) { > + cur += root->sectorsize; > + continue; > + } > + > + blk = (cur - ordered->file_offset) > + >> inode->i_sb->s_blocksize_bits; > + len = min(page_end, ordered->file_offset + ordered->len - 1) > + - cur + 1; > + nr_blks = len >> inode->i_sb->s_blocksize_bits; > + > + last_blk = blk + nr_blks - 1; > + > + outstanding_blk = find_next_zero_bit(ordered->blocks_done, > + ordered->len >> > inode->i_sb->s_blocksize_bits, > + blk); > + if (outstanding_blk <= last_blk) { > + btrfs_put_ordered_extent(ordered); > + return 0; > + } > + > + btrfs_put_ordered_extent(ordered); > + cur += len; > + } > + > + return 1; > } > > static void btrfs_invalidatepage(struct page *page, unsigned int offset, > - unsigned int length) > + unsigned int length) > { > struct inode *inode = page->mapping->host; > + struct btrfs_root *root = BTRFS_I(inode)->root; > struct extent_io_tree *tree; > struct btrfs_ordered_extent *ordered; > - struct extent_state *cached_state = NULL; > - u64 page_start = page_offset(page); > - u64 page_end = page_start + PAGE_CACHE_SIZE - 1; > + u64 start, end, cur; > + u64 page_start, page_end; > int inode_evicting = inode->i_state & I_FREEING; > > + page_start = page_offset(page); > + page_end = page_start + PAGE_CACHE_SIZE - 1; > + > /* > * we have the page locked, so new writeback can't start, > * and the dirty bit won't be cleared while we are here. > @@ -8515,73 +8694,54 @@ static void btrfs_invalidatepage(struct page *page, > unsigned int offset, > wait_on_page_writeback(page); > > tree = &BTRFS_I(inode)->io_tree; > - if (offset) { > + > + start = round_up(offset, root->sectorsize); > + end = round_down(offset + length, root->sectorsize) - 1; > + if (end - start + 1 < root->sectorsize) { > btrfs_releasepage(page, GFP_NOFS); > return; > } > > + start = round_up(page_start + offset, root->sectorsize); > + end = round_down(page_start + offset + length, > + root->sectorsize) - 1; > + > if (!inode_evicting) > - lock_extent_bits(tree, page_start, page_end, 0, &cached_state); > - ordered = btrfs_lookup_ordered_range(inode, page_start, > PAGE_CACHE_SIZE); > - if (ordered) { > - /* > - * IO on this page will never be started, so we need > - * to account for any ordered extents now > - */ > - if (!inode_evicting) > - clear_extent_bit(tree, page_start, page_end, > - EXTENT_DIRTY | EXTENT_DELALLOC | > - EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | > - EXTENT_DEFRAG, 1, 0, &cached_state, > - GFP_NOFS); > - /* > - * whoever cleared the private bit is responsible > - * for the finish_ordered_io > - */ > - if (TestClearPagePrivate2(page)) { > - struct btrfs_ordered_inode_tree *tree; > - u64 new_len; > + lock_extent_bits(tree, start, end, 0, NULL); > > - tree = &BTRFS_I(inode)->ordered_tree; > + cur = start; > + while (cur < end) { > + ordered = btrfs_lookup_ordered_extent(inode, cur); > + if (!ordered) { > + cur += root->sectorsize; > + continue; > + } > > - spin_lock_irq(&tree->lock); > - set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); > - new_len = page_start - ordered->file_offset; > - if (new_len < ordered->truncated_len) > - ordered->truncated_len = new_len; > - spin_unlock_irq(&tree->lock); > + invalidate_ordered_extent_blocks(inode, ordered, > + start, end, cur, > + inode_evicting); > > - if (btrfs_dec_test_ordered_pending(inode, &ordered, > - page_start, > - PAGE_CACHE_SIZE, 1)) > - btrfs_finish_ordered_io(ordered); > - } > + cur = min(end + 1, ordered->file_offset + ordered->len); > btrfs_put_ordered_extent(ordered); > - if (!inode_evicting) { > - cached_state = NULL; > - lock_extent_bits(tree, page_start, page_end, 0, > - &cached_state); > - } > } > > - if (!inode_evicting) { > - clear_extent_bit(tree, page_start, page_end, > - EXTENT_LOCKED | EXTENT_DIRTY | > - EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | > - EXTENT_DEFRAG, 1, 1, > - &cached_state, GFP_NOFS); > + if (page_blocks_written(page)) > + ClearPagePrivate2(page); > > - __btrfs_releasepage(page, GFP_NOFS); > + if (!inode_evicting) { > + clear_extent_bit(tree, start, end, > + EXTENT_LOCKED | EXTENT_DIRTY | > + EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | > + EXTENT_DEFRAG, 1, 1, NULL, GFP_NOFS); > } > > - ClearPageChecked(page); > - if (PagePrivate(page)) { > - ClearPagePrivate(page); > - set_page_private(page, 0); > - page_cache_release(page); > + if (!offset && length == PAGE_CACHE_SIZE) { > + WARN_ON(!__btrfs_releasepage(page, start, end, GFP_NOFS)); > + ClearPageChecked(page); > } > } > > + > /* > * btrfs_page_mkwrite() is not allowed to change the file size as it gets > * called from a page fault handler when a page is first dirtied. Hence we > must > diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c > index 157cc54..8e614ca 100644 > --- a/fs/btrfs/ordered-data.c > +++ b/fs/btrfs/ordered-data.c > @@ -189,12 +189,25 @@ static int __btrfs_add_ordered_extent(struct inode > *inode, u64 file_offset, > struct btrfs_ordered_inode_tree *tree; > struct rb_node *node; > struct btrfs_ordered_extent *entry; > + u64 nr_longs; > > tree = &BTRFS_I(inode)->ordered_tree; > entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS); > if (!entry) > return -ENOMEM; > > + nr_longs = BITS_TO_LONGS(len >> inode->i_sb->s_blocksize_bits); > + if (nr_longs == 1) { > + entry->blocks_done = &entry->blocks_bitmap; > + } else { > + entry->blocks_done = kzalloc(nr_longs * sizeof(unsigned long), > + GFP_NOFS); > + if (!entry->blocks_done) { > + kmem_cache_free(btrfs_ordered_extent_cache, entry); > + return -ENOMEM; > + } > + } > + > entry->file_offset = file_offset; > entry->start = start; > entry->len = len; > @@ -553,6 +566,10 @@ void btrfs_put_ordered_extent(struct > btrfs_ordered_extent *entry) > list_del(&sum->list); > kfree(sum); > } > + > + if (entry->blocks_done != &entry->blocks_bitmap) > + kfree(entry->blocks_done); > + > kmem_cache_free(btrfs_ordered_extent_cache, entry); > } > } > diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h > index e96cd4c..4b3356a 100644 > --- a/fs/btrfs/ordered-data.h > +++ b/fs/btrfs/ordered-data.h > @@ -140,6 +140,10 @@ struct btrfs_ordered_extent { > struct completion completion; > struct btrfs_work flush_work; > struct list_head work_list; > + > + /* bitmap to track the blocks that have been written to disk */ > + unsigned long *blocks_done; > + unsigned long blocks_bitmap; > }; > > /* > -- > 2.1.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html