From: Tao Ma Subject: [PATCH V4 04/22] ext4: Add read support for inline data. Date: Mon, 20 Feb 2012 15:01:38 +0800 Message-ID: <1329721316-4955-4-git-send-email-tm@tao.ma> References: <4F41EF95.2000909@tao.ma> <1329721316-4955-1-git-send-email-tm@tao.ma> Cc: linux-fsdevel@vger.kernel.org To: linux-ext4@vger.kernel.org Return-path: Received: from oproxy9.bluehost.com ([69.89.24.6]:53841 "HELO oproxy9.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751506Ab2BTHCe (ORCPT ); Mon, 20 Feb 2012 02:02:34 -0500 In-Reply-To: <1329721316-4955-1-git-send-email-tm@tao.ma> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Tao Ma Let readpage and readpages handle the case when we want to read an inlined file. Signed-off-by: Tao Ma index); + + if (!EXT4_I(inode)->i_inline_off) { + ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.", + inode->i_ino); + goto out; + } + + ret = ext4_get_inode_loc(inode, &iloc); + if (ret) + goto out; + + len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode)); + kaddr = kmap_atomic(page, KM_USER0); + ret = ext4_read_inline_data(inode, kaddr, len, &iloc); + flush_dcache_page(page); + kunmap_atomic(kaddr, KM_USER0); + zero_user_segment(page, len, PAGE_CACHE_SIZE); + SetPageUptodate(page); + brelse(iloc.bh); + +out: + return ret; +} + +int ext4_readpage_inline(struct inode *inode, struct page *page) +{ + int ret = 0; + + down_read(&EXT4_I(inode)->xattr_sem); + if (!ext4_has_inline_data(inode)) { + up_read(&EXT4_I(inode)->xattr_sem); + return -EAGAIN; + } + + /* + * Current inline data can only exist in the 1st page, + * So for all the other pages, just set them uptodate. + */ + if (!page->index) + ret = ext4_read_inline_page(inode, page); + else if (!PageUptodate(page)) { + zero_user_segment(page, 0, PAGE_CACHE_SIZE); + SetPageUptodate(page); + } + + up_read(&EXT4_I(inode)->xattr_sem); + + unlock_page(page); + return ret >= 0 ? 0 : ret; +} + int ext4_destroy_inline_data(handle_t *handle, struct inode *inode) { int ret; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b94a388..f631070 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -594,6 +594,9 @@ static int _ext4_get_block(struct inode *inode, sector_t iblock, int ret = 0, started = 0; int dio_credits; + if (ext4_has_inline_data(inode)) + return -ERANGE; + map.m_lblk = iblock; map.m_len = bh->b_size >> inode->i_blkbits; @@ -2620,6 +2623,12 @@ static sector_t ext4_bmap(struct address_space *mapping, sector_t block) journal_t *journal; int err; + /* + * XXX: Can we arrive here for a inline file? Maybe not. + */ + if (ext4_has_inline_data(inode)) + return 0; + if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && test_opt(inode->i_sb, DELALLOC)) { /* @@ -2665,14 +2674,30 @@ static sector_t ext4_bmap(struct address_space *mapping, sector_t block) static int ext4_readpage(struct file *file, struct page *page) { + int ret = -EAGAIN; + struct inode *inode = page->mapping->host; + trace_ext4_readpage(page); - return mpage_readpage(page, ext4_get_block); + + if (ext4_has_inline_data(inode)) + ret = ext4_readpage_inline(inode, page); + + if (ret == -EAGAIN) + return mpage_readpage(page, ext4_get_block); + + return ret; } static int ext4_readpages(struct file *file, struct address_space *mapping, struct list_head *pages, unsigned nr_pages) { + struct inode *inode = mapping->host; + + /* If the file has inline data, no need to do readpages. */ + if (ext4_has_inline_data(inode)) + return 0; + return mpage_readpages(mapping, pages, nr_pages, ext4_get_block); } @@ -2994,6 +3019,10 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb, if (ext4_should_journal_data(inode)) return 0; + /* Let buffer I/O handle the inline data case. */ + if (ext4_has_inline_data(inode)) + return 0; + trace_ext4_direct_IO_enter(inode, offset, iov_length(iov, nr_segs), rw); if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) ret = ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs); diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h index 2fe373f..8971d06 100644 --- a/fs/ext4/xattr.h +++ b/fs/ext4/xattr.h @@ -137,6 +137,8 @@ extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode, extern int ext4_init_inline_data(handle_t *handle, struct inode *inode, unsigned int len); extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode); + +extern int ext4_readpage_inline(struct inode *inode, struct page *page); # else /* CONFIG_EXT4_FS_XATTR */ static inline int @@ -252,6 +254,11 @@ static inline int ext4_destroy_inline_data(handle_t *handle, { return 0; } + +static inline int ext4_readpage_inline(struct inode *inode, struct page *page) +{ + return 0; +} # endif /* CONFIG_EXT4_FS_XATTR */ #ifdef CONFIG_EXT4_FS_SECURITY -- 1.7.0.4