X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fext4%2Finode.c;h=a08ec795995f3b50800e050c13dcc4f3a7d7bfaa;hb=a42afc5f56f319107e987aa6adf2f65d93d527c7;hp=4b8debeb39652fa0e10bcf36d397d6125c750d1a;hpb=c206d44ffdd539f5f4553e1a92cc7711084c1d3c;p=pandora-kernel.git

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4b8debeb3965..a08ec795995f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -60,6 +60,7 @@ static inline int ext4_begin_ordered_truncate(struct inode *inode,
 }
 
 static void ext4_invalidatepage(struct page *page, unsigned long offset);
+static int ext4_writepage(struct page *page, struct writeback_control *wbc);
 
 /*
  * Test whether an inode is a fast symlink.
@@ -1207,8 +1208,10 @@ static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
 				break;
 			idx++;
 			num++;
-			if (num >= max_pages)
+			if (num >= max_pages) {
+				done = 1;
 				break;
+			}
 		}
 		pagevec_release(&pvec);
 	}
@@ -2031,7 +2034,7 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd)
 			BUG_ON(PageWriteback(page));
 
 			pages_skipped = mpd->wbc->pages_skipped;
-			err = mapping->a_ops->writepage(page, mpd->wbc);
+			err = ext4_writepage(page, mpd->wbc);
 			if (!err && (pages_skipped == mpd->wbc->pages_skipped))
 				/*
 				 * have successfully written the page
@@ -2103,7 +2106,7 @@ static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd,
 			} while ((bh = bh->b_this_page) != head);
 
 			do {
-				if (cur_logical >= map->m_lblk + blocks)
+				if (cur_logical > map->m_lblk + (blocks - 1))
 					break;
 
 				if (buffer_delay(bh) || buffer_unwritten(bh)) {
@@ -2187,14 +2190,15 @@ static void ext4_print_free_blocks(struct inode *inode)
 }
 
 /*
- * mpage_da_map_blocks - go through given space
+ * mpage_da_map_and_submit - go through given space, map them
+ *       if necessary, and then submit them for I/O
  *
  * @mpd - bh describing space
  *
  * The function skips space we know is already mapped to disk blocks.
  *
  */
-static int mpage_da_map_blocks(struct mpage_da_data *mpd)
+static void mpage_da_map_and_submit(struct mpage_da_data *mpd)
 {
 	int err, blks, get_blocks_flags;
 	struct ext4_map_blocks map;
@@ -2204,18 +2208,14 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 	handle_t *handle = NULL;
 
 	/*
-	 * We consider only non-mapped and non-allocated blocks
-	 */
-	if ((mpd->b_state  & (1 << BH_Mapped)) &&
-		!(mpd->b_state & (1 << BH_Delay)) &&
-		!(mpd->b_state & (1 << BH_Unwritten)))
-		return 0;
-
-	/*
-	 * If we didn't accumulate anything to write simply return
+	 * If the blocks are mapped already, or we couldn't accumulate
+	 * any blocks, then proceed immediately to the submission stage.
 	 */
-	if (!mpd->b_size)
-		return 0;
+	if ((mpd->b_size == 0) ||
+	    ((mpd->b_state  & (1 << BH_Mapped)) &&
+	     !(mpd->b_state & (1 << BH_Delay)) &&
+	     !(mpd->b_state & (1 << BH_Unwritten))))
+		goto submit_io;
 
 	handle = ext4_journal_current_handle();
 	BUG_ON(!handle);
@@ -2252,17 +2252,18 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 
 		err = blks;
 		/*
-		 * If get block returns with error we simply
-		 * return. Later writepage will redirty the page and
-		 * writepages will find the dirty page again
+		 * If get block returns EAGAIN or ENOSPC and there
+		 * appears to be free blocks we will call
+		 * ext4_writepage() for all of the pages which will
+		 * just redirty the pages.
 		 */
 		if (err == -EAGAIN)
-			return 0;
+			goto submit_io;
 
 		if (err == -ENOSPC &&
 		    ext4_count_free_blocks(sb)) {
 			mpd->retval = err;
-			return 0;
+			goto submit_io;
 		}
 
 		/*
@@ -2287,7 +2288,7 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 		/* invalidate all the pages */
 		ext4_da_block_invalidatepages(mpd, next,
 				mpd->b_size >> mpd->inode->i_blkbits);
-		return err;
+		return;
 	}
 	BUG_ON(blks == 0);
 
@@ -2310,7 +2311,8 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 	if (ext4_should_order_data(mpd->inode)) {
 		err = ext4_jbd2_file_inode(handle, mpd->inode);
 		if (err)
-			return err;
+			/* This only happens if the journal is aborted */
+			return;
 	}
 
 	/*
@@ -2321,10 +2323,16 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 		disksize = i_size_read(mpd->inode);
 	if (disksize > EXT4_I(mpd->inode)->i_disksize) {
 		ext4_update_i_disksize(mpd->inode, disksize);
-		return ext4_mark_inode_dirty(handle, mpd->inode);
+		err = ext4_mark_inode_dirty(handle, mpd->inode);
+		if (err)
+			ext4_error(mpd->inode->i_sb,
+				   "Failed to mark inode %lu dirty",
+				   mpd->inode->i_ino);
 	}
 
-	return 0;
+submit_io:
+	mpage_da_submit_io(mpd);
+	mpd->io_done = 1;
 }
 
 #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
@@ -2401,9 +2409,7 @@ flush_it:
 	 * We couldn't merge the block to our extent, so we
 	 * need to flush current  extent and start new one
 	 */
-	if (mpage_da_map_blocks(mpd) == 0)
-		mpage_da_submit_io(mpd);
-	mpd->io_done = 1;
+	mpage_da_map_and_submit(mpd);
 	return;
 }
 
@@ -2435,15 +2441,13 @@ static int __mpage_da_writepage(struct page *page,
 	if (mpd->next_page != page->index) {
 		/*
 		 * Nope, we can't. So, we map non-allocated blocks
-		 * and start IO on them using writepage()
+		 * and start IO on them
 		 */
 		if (mpd->next_page != mpd->first_page) {
-			if (mpage_da_map_blocks(mpd) == 0)
-				mpage_da_submit_io(mpd);
+			mpage_da_map_and_submit(mpd);
 			/*
 			 * skip rest of the page in the page_vec
 			 */
-			mpd->io_done = 1;
 			redirty_page_for_writepage(wbc, page);
 			unlock_page(page);
 			return MPAGE_DA_EXTENT_TAIL;
@@ -2700,7 +2704,7 @@ static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate);
 static int ext4_writepage(struct page *page,
 			  struct writeback_control *wbc)
 {
-	int ret = 0;
+	int ret = 0, commit_write = 0;
 	loff_t size;
 	unsigned int len;
 	struct buffer_head *page_bufs = NULL;
@@ -2713,60 +2717,37 @@ static int ext4_writepage(struct page *page,
 	else
 		len = PAGE_CACHE_SIZE;
 
-	if (page_has_buffers(page)) {
-		page_bufs = page_buffers(page);
-		if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
-					ext4_bh_delay_or_unwritten)) {
-			/*
-			 * We don't want to do  block allocation
-			 * So redirty the page and return
-			 * We may reach here when we do a journal commit
-			 * via journal_submit_inode_data_buffers.
-			 * If we don't have mapping block we just ignore
-			 * them. We can also reach here via shrink_page_list
-			 */
+	/*
+	 * If the page does not have buffers (for whatever reason),
+	 * try to create them using block_prepare_write.  If this
+	 * fails, redirty the page and move on.
+	 */
+	if (!page_buffers(page)) {
+		if (block_prepare_write(page, 0, len,
+					noalloc_get_block_write)) {
+		redirty_page:
 			redirty_page_for_writepage(wbc, page);
 			unlock_page(page);
 			return 0;
 		}
-	} else {
+		commit_write = 1;
+	}
+	page_bufs = page_buffers(page);
+	if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+			      ext4_bh_delay_or_unwritten)) {
 		/*
-		 * The test for page_has_buffers() is subtle:
-		 * We know the page is dirty but it lost buffers. That means
-		 * that at some moment in time after write_begin()/write_end()
-		 * has been called all buffers have been clean and thus they
-		 * must have been written at least once. So they are all
-		 * mapped and we can happily proceed with mapping them
-		 * and writing the page.
-		 *
-		 * Try to initialize the buffer_heads and check whether
-		 * all are mapped and non delay. We don't want to
-		 * do block allocation here.
+		 * We don't want to do block allocation So redirty the
+		 * page and return We may reach here when we do a
+		 * journal commit via
+		 * journal_submit_inode_data_buffers.  If we don't
+		 * have mapping block we just ignore them. We can also
+		 * reach here via shrink_page_list
 		 */
-		ret = block_prepare_write(page, 0, len,
-					  noalloc_get_block_write);
-		if (!ret) {
-			page_bufs = page_buffers(page);
-			/* check whether all are mapped and non delay */
-			if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
-						ext4_bh_delay_or_unwritten)) {
-				redirty_page_for_writepage(wbc, page);
-				unlock_page(page);
-				return 0;
-			}
-		} else {
-			/*
-			 * We can't do block allocation here
-			 * so just redity the page and unlock
-			 * and return
-			 */
-			redirty_page_for_writepage(wbc, page);
-			unlock_page(page);
-			return 0;
-		}
+		goto redirty_page;
+	}
+	if (commit_write)
 		/* now mark the buffer_heads as dirty and uptodate */
 		block_commit_write(page, 0, len);
-	}
 
 	if (PageChecked(page) && ext4_should_journal_data(inode)) {
 		/*
@@ -2777,7 +2758,7 @@ static int ext4_writepage(struct page *page,
 		return __ext4_journalled_writepage(page, len);
 	}
 
-	if (page_bufs && buffer_uninit(page_bufs)) {
+	if (buffer_uninit(page_bufs)) {
 		ext4_set_bh_endio(page_bufs, inode);
 		ret = block_write_full_page_endio(page, noalloc_get_block_write,
 					    wbc, ext4_end_io_buffer_write);
@@ -3002,9 +2983,12 @@ static int ext4_da_writepages(struct address_space *mapping,
 	 * sbi->max_writeback_mb_bump whichever is smaller.
 	 */
 	max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT);
-	if (!range_cyclic && range_whole)
-		desired_nr_to_write = wbc->nr_to_write * 8;
-	else
+	if (!range_cyclic && range_whole) {
+		if (wbc->nr_to_write == LONG_MAX)
+			desired_nr_to_write = wbc->nr_to_write;
+		else
+			desired_nr_to_write = wbc->nr_to_write * 8;
+	} else
 		desired_nr_to_write = ext4_num_dirty_pages(inode, index,
 							   max_pages);
 	if (desired_nr_to_write > max_pages)
@@ -3066,9 +3050,7 @@ retry:
 		 * them for I/O.
 		 */
 		if (!mpd.io_done && mpd.next_page != mpd.first_page) {
-			if (mpage_da_map_blocks(&mpd) == 0)
-				mpage_da_submit_io(&mpd);
-			mpd.io_done = 1;
+			mpage_da_map_and_submit(&mpd);
 			ret = MPAGE_DA_EXTENT_TAIL;
 		}
 		trace_ext4_da_write_pages(inode, &mpd);
@@ -3845,14 +3827,14 @@ out:
 	}
 	wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
 
-	/* queue the work to convert unwritten extents to written */
-	queue_work(wq, &io_end->work);
-
 	/* Add the io_end to per-inode completed aio dio list*/
 	ei = EXT4_I(io_end->inode);
 	spin_lock_irqsave(&ei->i_completed_io_lock, flags);
 	list_add_tail(&io_end->list, &ei->i_completed_io_list);
 	spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
+
+	/* queue the work to convert unwritten extents to written */
+	queue_work(wq, &io_end->work);
 	iocb->private = NULL;
 }