Cc: linux-ext4@vger.kernel.org Cc: Linux Filesystems Convert ext4 to use write_begin()/write_end() methods. Signed-off-by: Badari Pulavarty fs/ext4/inode.c | 147 +++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 93 insertions(+), 54 deletions(-) Index: linux-2.6/fs/ext4/inode.c =================================================================== --- linux-2.6.orig/fs/ext4/inode.c +++ linux-2.6/fs/ext4/inode.c @@ -1146,34 +1146,50 @@ static int do_journal_get_write_access(h return ext4_journal_get_write_access(handle, bh); } -static int ext4_prepare_write(struct file *file, struct page *page, - unsigned from, unsigned to) +static int ext4_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) { - struct inode *inode = page->mapping->host; + struct inode *inode = mapping->host; int ret, needed_blocks = ext4_writepage_trans_blocks(inode); handle_t *handle; int retries = 0; + struct page *page; + pgoff_t index; + unsigned from, to; + + index = pos >> PAGE_CACHE_SHIFT; + from = pos & (PAGE_CACHE_SIZE - 1); + to = from + len; retry: - handle = ext4_journal_start(inode, needed_blocks); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto out; + page = __grab_cache_page(mapping, index); + if (!page) + return -ENOMEM; + *pagep = page; + + handle = ext4_journal_start(inode, needed_blocks); + if (IS_ERR(handle)) { + unlock_page(page); + page_cache_release(page); + ret = PTR_ERR(handle); + goto out; } - if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) - ret = nobh_prepare_write(page, from, to, ext4_get_block); - else - ret = block_prepare_write(page, from, to, ext4_get_block); - if (ret) - goto prepare_write_failed; - if (ext4_should_journal_data(inode)) { + ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, + ext4_get_block); + + if (!ret && ext4_should_journal_data(inode)) { ret = walk_page_buffers(handle, page_buffers(page), from, to, NULL, do_journal_get_write_access); } -prepare_write_failed: - if (ret) + + if (ret) { ext4_journal_stop(handle); + unlock_page(page); + page_cache_release(page); + } + if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) goto retry; out: @@ -1185,12 +1201,12 @@ int ext4_journal_dirty_data(handle_t *ha int err = jbd2_journal_dirty_data(handle, bh); if (err) ext4_journal_abort_handle(__FUNCTION__, __FUNCTION__, - bh, handle,err); + bh, handle, err); return err; } -/* For commit_write() in data=journal mode */ -static int commit_write_fn(handle_t *handle, struct buffer_head *bh) +/* For write_end() in data=journal mode */ +static int write_end_fn(handle_t *handle, struct buffer_head *bh) { if (!buffer_mapped(bh) || buffer_freed(bh)) return 0; @@ -1205,78 +1221,100 @@ static int commit_write_fn(handle_t *han * ext4 never places buffers on inode->i_mapping->private_list. metadata * buffers are managed internally. */ -static int ext4_ordered_commit_write(struct file *file, struct page *page, - unsigned from, unsigned to) +static int ext4_ordered_write_end(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) { handle_t *handle = ext4_journal_current_handle(); - struct inode *inode = page->mapping->host; + struct inode *inode = file->f_mapping->host; + unsigned from, to; int ret = 0, ret2; + from = pos & (PAGE_CACHE_SIZE - 1); + to = from + len; + ret = walk_page_buffers(handle, page_buffers(page), from, to, NULL, ext4_journal_dirty_data); if (ret == 0) { /* - * generic_commit_write() will run mark_inode_dirty() if i_size + * generic_write_end() will run mark_inode_dirty() if i_size * changes. So let's piggyback the i_disksize mark_inode_dirty * into that. */ loff_t new_i_size; - new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; + new_i_size = pos + copied; if (new_i_size > EXT4_I(inode)->i_disksize) EXT4_I(inode)->i_disksize = new_i_size; - ret = generic_commit_write(file, page, from, to); + copied = generic_write_end(file, mapping, pos, len, copied, + page, fsdata); + if (copied < 0) + ret = copied; + } else { + unlock_page(page); + page_cache_release(page); } ret2 = ext4_journal_stop(handle); if (!ret) ret = ret2; - return ret; + return ret ? ret : copied; } -static int ext4_writeback_commit_write(struct file *file, struct page *page, - unsigned from, unsigned to) +static int ext4_writeback_write_end(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) { handle_t *handle = ext4_journal_current_handle(); - struct inode *inode = page->mapping->host; + struct inode *inode = file->f_mapping->host; int ret = 0, ret2; loff_t new_i_size; - new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; + new_i_size = pos + copied; if (new_i_size > EXT4_I(inode)->i_disksize) EXT4_I(inode)->i_disksize = new_i_size; - if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) - ret = nobh_commit_write(file, page, from, to); - else - ret = generic_commit_write(file, page, from, to); + copied = generic_write_end(file, mapping, pos, len, copied, + page, fsdata); + if (copied < 0) + ret = copied; ret2 = ext4_journal_stop(handle); if (!ret) ret = ret2; - return ret; + return ret ? ret : copied; } -static int ext4_journalled_commit_write(struct file *file, - struct page *page, unsigned from, unsigned to) +static int ext4_journalled_write_end(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) { handle_t *handle = ext4_journal_current_handle(); - struct inode *inode = page->mapping->host; + struct inode *inode = mapping->host; int ret = 0, ret2; int partial = 0; - loff_t pos; + unsigned from, to; - /* - * Here we duplicate the generic_commit_write() functionality - */ - pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; + from = pos & (PAGE_CACHE_SIZE - 1); + to = from + len; + + if (copied < len) { + if (!PageUptodate(page)) + copied = 0; + page_zero_new_buffers(page, from+copied, to); + } ret = walk_page_buffers(handle, page_buffers(page), from, - to, &partial, commit_write_fn); + to, &partial, write_end_fn); if (!partial) SetPageUptodate(page); - if (pos > inode->i_size) - i_size_write(inode, pos); + unlock_page(page); + page_cache_release(page); + if (pos+copied > inode->i_size) + i_size_write(inode, pos+copied); EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; if (inode->i_size > EXT4_I(inode)->i_disksize) { EXT4_I(inode)->i_disksize = inode->i_size; @@ -1284,10 +1322,11 @@ static int ext4_journalled_commit_write( if (!ret) ret = ret2; } + ret2 = ext4_journal_stop(handle); if (!ret) ret = ret2; - return ret; + return ret ? ret : copied; } /* @@ -1545,7 +1584,7 @@ static int ext4_journalled_writepage(str PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); err = walk_page_buffers(handle, page_buffers(page), 0, - PAGE_CACHE_SIZE, NULL, commit_write_fn); + PAGE_CACHE_SIZE, NULL, write_end_fn); if (ret == 0) ret = err; EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; @@ -1705,8 +1744,8 @@ static const struct address_space_operat .readpages = ext4_readpages, .writepage = ext4_ordered_writepage, .sync_page = block_sync_page, - .prepare_write = ext4_prepare_write, - .commit_write = ext4_ordered_commit_write, + .write_begin = ext4_write_begin, + .write_end = ext4_ordered_write_end, .bmap = ext4_bmap, .invalidatepage = ext4_invalidatepage, .releasepage = ext4_releasepage, @@ -1719,8 +1758,8 @@ static const struct address_space_operat .readpages = ext4_readpages, .writepage = ext4_writeback_writepage, .sync_page = block_sync_page, - .prepare_write = ext4_prepare_write, - .commit_write = ext4_writeback_commit_write, + .write_begin = ext4_write_begin, + .write_end = ext4_writeback_write_end, .bmap = ext4_bmap, .invalidatepage = ext4_invalidatepage, .releasepage = ext4_releasepage, @@ -1733,8 +1772,8 @@ static const struct address_space_operat .readpages = ext4_readpages, .writepage = ext4_journalled_writepage, .sync_page = block_sync_page, - .prepare_write = ext4_prepare_write, - .commit_write = ext4_journalled_commit_write, + .write_begin = ext4_write_begin, + .write_end = ext4_journalled_write_end, .set_page_dirty = ext4_journalled_set_page_dirty, .bmap = ext4_bmap, .invalidatepage = ext4_invalidatepage, -- - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html