From: Theodore Ts'o Subject: [PATCH 15/42] ext4: Properly update i_disksize. Date: Thu, 9 Oct 2008 00:05:33 -0400 Message-ID: <1223525160-9887-16-git-send-email-tytso@mit.edu> References: <1223525160-9887-1-git-send-email-tytso@mit.edu> <1223525160-9887-2-git-send-email-tytso@mit.edu> <1223525160-9887-3-git-send-email-tytso@mit.edu> <1223525160-9887-4-git-send-email-tytso@mit.edu> <1223525160-9887-5-git-send-email-tytso@mit.edu> <1223525160-9887-6-git-send-email-tytso@mit.edu> <1223525160-9887-7-git-send-email-tytso@mit.edu> <1223525160-9887-8-git-send-email-tytso@mit.edu> <1223525160-9887-9-git-send-email-tytso@mit.edu> <1223525160-9887-10-git-send-email-tytso@mit.edu> <1223525160-9887-11-git-send-email-tytso@mit.edu> <1223525160-9887-12-git-send-email-tytso@mit.edu> <1223525160-9887-13-git-send-email-tytso@mit.edu> <1223525160-9887-14-git-send-email-tytso@mit.edu> <1223525160-9887-15-git-send-email-tytso@mit.edu> Cc: "Aneesh Kumar K.V" , "Theodore Ts'o" To: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from www.church-of-our-saviour.org ([69.25.196.31]:54528 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756043AbYJIEGN (ORCPT ); Thu, 9 Oct 2008 00:06:13 -0400 In-Reply-To: <1223525160-9887-15-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Aneesh Kumar K.V With delayed allocation we use i_data_sem to update i_disksize. We need to update i_disksize only if the new size specified is greater than the current value and we need to make sure we don't race with other i_disksize update. With delayed allocation we will switch to the write_begin function for non-delayed allocation if we are low on free blocks. This means the write_begin function for non-delayed allocation also needs to use the same locking. We also need to check and update i_disksize even if the new size is less that inode.i_size because of delayed allocation. Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 11 ++++++++++ fs/ext4/extents.c | 9 ++++--- fs/ext4/inode.c | 54 +++++++++++++++++++++++++++++----------------------- 3 files changed, 46 insertions(+), 28 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index e13b9de..3e47b99 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1218,6 +1218,17 @@ do { \ #define EXT4_FREEBLOCKS_WATERMARK 0 #endif +static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize) +{ + /* + * XXX: replace with spinlock if seen contended -bzzz + */ + down_write(&EXT4_I(inode)->i_data_sem); + if (newsize > EXT4_I(inode)->i_disksize) + EXT4_I(inode)->i_disksize = newsize; + up_write(&EXT4_I(inode)->i_data_sem); + return ; +} /* * Inodes and files operations diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 797f060..e8758df 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2878,10 +2878,11 @@ static void ext4_falloc_update_inode(struct inode *inode, * Update only when preallocation was requested beyond * the file size. */ - if (!(mode & FALLOC_FL_KEEP_SIZE) && - new_size > i_size_read(inode)) { - i_size_write(inode, new_size); - EXT4_I(inode)->i_disksize = new_size; + if (!(mode & FALLOC_FL_KEEP_SIZE)) { + if (new_size > i_size_read(inode)) + i_size_write(inode, new_size); + if (new_size > EXT4_I(inode)->i_disksize) + ext4_update_i_disksize(inode, new_size); } } diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 634f0bc..22fcbb6 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1434,16 +1434,18 @@ static int ext4_ordered_write_end(struct file *file, ret = ext4_jbd2_file_inode(handle, inode); if (ret == 0) { - /* - * 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 = pos + copied; - if (new_i_size > EXT4_I(inode)->i_disksize) - EXT4_I(inode)->i_disksize = new_i_size; + if (new_i_size > EXT4_I(inode)->i_disksize) { + ext4_update_i_disksize(inode, new_i_size); + /* We need to mark inode dirty even if + * new_i_size is less that inode->i_size + * bu greater than i_disksize.(hint delalloc) + */ + ext4_mark_inode_dirty(handle, inode); + } + ret2 = generic_write_end(file, mapping, pos, len, copied, page, fsdata); copied = ret2; @@ -1468,8 +1470,14 @@ static int ext4_writeback_write_end(struct file *file, loff_t new_i_size; new_i_size = pos + copied; - if (new_i_size > EXT4_I(inode)->i_disksize) - EXT4_I(inode)->i_disksize = new_i_size; + if (new_i_size > EXT4_I(inode)->i_disksize) { + ext4_update_i_disksize(inode, new_i_size); + /* We need to mark inode dirty even if + * new_i_size is less that inode->i_size + * bu greater than i_disksize.(hint delalloc) + */ + ext4_mark_inode_dirty(handle, inode); + } ret2 = generic_write_end(file, mapping, pos, len, copied, page, fsdata); @@ -1494,6 +1502,7 @@ static int ext4_journalled_write_end(struct file *file, int ret = 0, ret2; int partial = 0; unsigned from, to; + loff_t new_i_size; from = pos & (PAGE_CACHE_SIZE - 1); to = from + len; @@ -1508,11 +1517,12 @@ static int ext4_journalled_write_end(struct file *file, to, &partial, write_end_fn); if (!partial) SetPageUptodate(page); - if (pos+copied > inode->i_size) + new_i_size = pos + copied; + if (new_i_size > 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; + if (new_i_size > EXT4_I(inode)->i_disksize) { + ext4_update_i_disksize(inode, new_i_size); ret2 = ext4_mark_inode_dirty(handle, inode); if (!ret) ret = ret2; @@ -2227,18 +2237,9 @@ static int ext4_da_get_block_write(struct inode *inode, sector_t iblock, if (disksize > i_size_read(inode)) disksize = i_size_read(inode); if (disksize > EXT4_I(inode)->i_disksize) { - /* - * XXX: replace with spinlock if seen contended -bzzz - */ - down_write(&EXT4_I(inode)->i_data_sem); - if (disksize > EXT4_I(inode)->i_disksize) - EXT4_I(inode)->i_disksize = disksize; - up_write(&EXT4_I(inode)->i_data_sem); - - if (EXT4_I(inode)->i_disksize == disksize) { - ret = ext4_mark_inode_dirty(handle, inode); - return ret; - } + ext4_update_i_disksize(inode, disksize); + ret = ext4_mark_inode_dirty(handle, inode); + return ret; } ret = 0; } @@ -2654,6 +2655,11 @@ static int ext4_da_write_end(struct file *file, EXT4_I(inode)->i_disksize = new_i_size; } up_write(&EXT4_I(inode)->i_data_sem); + /* We need to mark inode dirty even if + * new_i_size is less that inode->i_size + * bu greater than i_disksize.(hint delalloc) + */ + ext4_mark_inode_dirty(handle, inode); } } ret2 = generic_write_end(file, mapping, pos, len, copied, -- 1.5.6.1.205.ge2c7.dirty