From fa5d11133b07053270e18fa9c18560e66e79217e Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Mon, 2 Nov 2009 18:50:49 -0500 Subject: ext4: discard preallocation when restarting a transaction during truncate When restart a transaction during a truncate operation, we drop and reacquire i_data_sem. After reacquiring i_data_sem, we need to discard any inode-based preallocation that might have been grabbed while we released i_data_sem (for example, if pdflush is allocating blocks and racing against the truncate). Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/ext4/inode.c') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 5c5bc5dafff8..d1ec698a91d1 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -193,7 +193,7 @@ static int try_to_extend_transaction(handle_t *handle, struct inode *inode) * so before we call here everything must be consistently dirtied against * this transaction. */ - int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode, +int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode, int nblocks) { int ret; @@ -209,6 +209,7 @@ static int try_to_extend_transaction(handle_t *handle, struct inode *inode) up_write(&EXT4_I(inode)->i_data_sem); ret = ext4_journal_restart(handle, blocks_for_truncate(inode)); down_write(&EXT4_I(inode)->i_data_sem); + ext4_discard_preallocations(inode); return ret; } -- cgit v1.2.1 From 109f55651954def97fa41ee71c464d268c512ab0 Mon Sep 17 00:00:00 2001 From: Mingming Date: Tue, 10 Nov 2009 10:48:08 -0500 Subject: ext4: fix ext4_ext_direct_IO()'s return value after converting uninit extents After a direct I/O request covering an uninitalized extent (i.e., created using the fallocate system call) or a hole in a file, ext4 will convert the uninitialized extent so it is marked as initialized by calling ext4_convert_unwritten_extents(). This function returns zero on success. This return value was getting returned by ext4_direct_IO(); however the file system's direct_IO function is supposed to return the number of bytes read or written on a success. By returning zero, it confused the direct I/O code into falling back to buffered I/O unnecessarily. Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'fs/ext4/inode.c') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index d1ec698a91d1..12d727f8fedf 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3772,13 +3772,17 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) { ext4_free_io_end(iocb->private); iocb->private = NULL; - } else if (ret > 0) + } else if (ret > 0) { + int err; /* * for non AIO case, since the IO is already * completed, we could do the convertion right here */ - ret = ext4_convert_unwritten_extents(inode, - offset, ret); + err = ext4_convert_unwritten_extents(inode, + offset, ret); + if (err < 0) + ret = err; + } return ret; } -- cgit v1.2.1 From 5f5249507e4b5c4fc0f9c93f33d133d8c95f47e1 Mon Sep 17 00:00:00 2001 From: Mingming Date: Tue, 10 Nov 2009 10:48:04 -0500 Subject: ext4: skip conversion of uninit extents after direct IO if there isn't any At the end of direct I/O operation, ext4_ext_direct_IO() always called ext4_convert_unwritten_extents(), regardless of whether there were any unwritten extents involved in the I/O or not. This commit adds a state flag so that ext4_ext_direct_IO() only calls ext4_convert_unwritten_extents() when necessary. Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs/ext4/inode.c') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 12d727f8fedf..a9ed2bce74d1 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3772,7 +3772,8 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) { ext4_free_io_end(iocb->private); iocb->private = NULL; - } else if (ret > 0) { + } else if (ret > 0 && (EXT4_I(inode)->i_state & + EXT4_STATE_DIO_UNWRITTEN)) { int err; /* * for non AIO case, since the IO is already @@ -3782,6 +3783,7 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, offset, ret); if (err < 0) ret = err; + EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN; } return ret; } -- cgit v1.2.1 From 4b70df181611012a3556f017b57dfcef7e1d279f Mon Sep 17 00:00:00 2001 From: Mingming Date: Tue, 3 Nov 2009 14:44:54 -0500 Subject: ext4: code clean up for dio fallocate handling The ext4_debug() call in ext4_end_io_dio() should be moved after the check to make sure that io_end is non-NULL. The comment above ext4_get_block_dio_write() ("Maximum number of blocks...") is a duplicate; the original and correct comment is above the #define DIO_MAX_BLOCKS up above. Based on review comments from Curt Wohlgemuth. Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'fs/ext4/inode.c') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index a9ed2bce74d1..2c8caa51addb 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3446,8 +3446,6 @@ out: return ret; } -/* Maximum number of blocks we map for direct IO at once. */ - static int ext4_get_block_dio_write(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -3655,13 +3653,14 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset, ext4_io_end_t *io_end = iocb->private; struct workqueue_struct *wq; + /* if not async direct IO or dio with 0 bytes write, just return */ + if (!io_end || !size) + return; + ext_debug("ext4_end_io_dio(): io_end 0x%p" "for inode %lu, iocb 0x%p, offset %llu, size %llu\n", iocb->private, io_end->inode->i_ino, iocb, offset, size); - /* if not async direct IO or dio with 0 bytes write, just return */ - if (!io_end || !size) - return; /* if not aio dio with unwritten extents, just free io and return */ if (io_end->flag != DIO_AIO_UNWRITTEN){ -- cgit v1.2.1