From: Steven Whitehouse Date: Fri, 28 Sep 2007 12:49:05 +0000 (+0100) Subject: [GFS2] Split gfs2_writepage into three cases X-Git-Tag: v2.6.25-rc1~1241^2~48 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=9ff8ec32e58875022447af619bec6e5aee7c77e4;p=linux-2.6-omap-h63xx.git [GFS2] Split gfs2_writepage into three cases This patch splits gfs2_writepage into separate functions for each of the three cases: writeback, ordered and journalled. As a result it becomes a lot easier to see what each one is doing. The common code is moved into gfs2_writepage_common. This fixes a performance bug where we were doing more work than strictly required in the ordered write case. Signed-off-by: Steven Whitehouse --- diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index 6c27cea761c..e901f8f7d65 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -556,17 +556,20 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) lock_buffer(bd->bd_bh); gfs2_log_lock(sdp); - if (!list_empty(&bd->bd_list_tr)) - goto out; - tr->tr_touched = 1; - if (gfs2_is_jdata(ip)) { - tr->tr_num_buf++; - list_add(&bd->bd_list_tr, &tr->tr_list_buf); + if (tr) { + if (!list_empty(&bd->bd_list_tr)) + goto out; + tr->tr_touched = 1; + if (gfs2_is_jdata(ip)) { + tr->tr_num_buf++; + list_add(&bd->bd_list_tr, &tr->tr_list_buf); + } } if (!list_empty(&le->le_list)) goto out; - __glock_lo_add(sdp, &bd->bd_gl->gl_le); + if (tr) + __glock_lo_add(sdp, &bd->bd_gl->gl_le); if (gfs2_is_jdata(ip)) { gfs2_pin(sdp, bd->bd_bh); tr->tr_num_databuf_new++; diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c index 207014f363d..4bf73ed945a 100644 --- a/fs/gfs2/ops_address.c +++ b/fs/gfs2/ops_address.c @@ -103,16 +103,15 @@ static int gfs2_get_block_direct(struct inode *inode, sector_t lblock, } /** - * gfs2_writepage - Write complete page - * @page: Page to write - * - * Returns: errno + * gfs2_writepage_common - Common bits of writepage + * @page: The page to be written + * @wbc: The writeback control * - * Some of this is copied from block_write_full_page() although we still - * call it to do most of the work. + * Returns: 1 if writepage is ok, otherwise an error code or zero if no error. */ -static int gfs2_writepage(struct page *page, struct writeback_control *wbc) +static int gfs2_writepage_common(struct page *page, + struct writeback_control *wbc) { struct inode *inode = page->mapping->host; struct gfs2_inode *ip = GFS2_I(inode); @@ -120,23 +119,94 @@ static int gfs2_writepage(struct page *page, struct writeback_control *wbc) loff_t i_size = i_size_read(inode); pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; unsigned offset; - int error; - int done_trans = 0; + int ret = -EIO; - if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) { - unlock_page(page); - return -EIO; - } + if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) + goto out; + ret = 0; if (current->journal_info) - goto out_ignore; - + goto redirty; /* Is the page fully outside i_size? (truncate in progress) */ - offset = i_size & (PAGE_CACHE_SIZE-1); + offset = i_size & (PAGE_CACHE_SIZE-1); if (page->index > end_index || (page->index == end_index && !offset)) { page->mapping->a_ops->invalidatepage(page, 0); - unlock_page(page); - return 0; /* don't care */ + goto out; } + return 1; +redirty: + redirty_page_for_writepage(wbc, page); +out: + unlock_page(page); + return 0; +} + +/** + * gfs2_writeback_writepage - Write page for writeback mappings + * @page: The page + * @wbc: The writeback control + * + */ + +static int gfs2_writeback_writepage(struct page *page, + struct writeback_control *wbc) +{ + int ret; + + ret = gfs2_writepage_common(page, wbc); + if (ret <= 0) + return ret; + + ret = mpage_writepage(page, gfs2_get_block_noalloc, wbc); + if (ret == -EAGAIN) + ret = block_write_full_page(page, gfs2_get_block_noalloc, wbc); + return ret; +} + +/** + * gfs2_ordered_writepage - Write page for ordered data files + * @page: The page to write + * @wbc: The writeback control + * + */ + +static int gfs2_ordered_writepage(struct page *page, + struct writeback_control *wbc) +{ + struct inode *inode = page->mapping->host; + struct gfs2_inode *ip = GFS2_I(inode); + int ret; + + ret = gfs2_writepage_common(page, wbc); + if (ret <= 0) + return ret; + + if (!page_has_buffers(page)) { + create_empty_buffers(page, inode->i_sb->s_blocksize, + (1 << BH_Dirty)|(1 << BH_Uptodate)); + } + gfs2_page_add_databufs(ip, page, 0, inode->i_sb->s_blocksize-1); + return block_write_full_page(page, gfs2_get_block_noalloc, wbc); +} + +/** + * gfs2_jdata_writepage - Write complete page + * @page: Page to write + * + * Returns: errno + * + */ + +static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc) +{ + struct inode *inode = page->mapping->host; + struct gfs2_inode *ip = GFS2_I(inode); + struct gfs2_sbd *sdp = GFS2_SB(inode); + int error; + int done_trans = 0; + + error = gfs2_writepage_common(page, wbc); + if (error <= 0) + return error; if (PageChecked(page)) { error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0); @@ -838,7 +908,7 @@ cannot_release: } static const struct address_space_operations gfs2_writeback_aops = { - .writepage = gfs2_writepage, + .writepage = gfs2_writeback_writepage, .writepages = gfs2_writeback_writepages, .readpage = gfs2_readpage, .readpages = gfs2_readpages, @@ -852,7 +922,7 @@ static const struct address_space_operations gfs2_writeback_aops = { }; static const struct address_space_operations gfs2_ordered_aops = { - .writepage = gfs2_writepage, + .writepage = gfs2_ordered_writepage, .readpage = gfs2_readpage, .readpages = gfs2_readpages, .sync_page = block_sync_page, @@ -866,7 +936,7 @@ static const struct address_space_operations gfs2_ordered_aops = { }; static const struct address_space_operations gfs2_jdata_aops = { - .writepage = gfs2_writepage, + .writepage = gfs2_jdata_writepage, .readpage = gfs2_readpage, .readpages = gfs2_readpages, .sync_page = block_sync_page,