diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 4eb308aa3234..a6abbae8a278 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -569,6 +569,40 @@ static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync) return ret; } +/** + * gfs2_file_aio_write - Perform a write to a file + * @iocb: The io context + * @iov: The data to write + * @nr_segs: Number of @iov segments + * @pos: The file position + * + * We have to do a lock/unlock here to refresh the inode size for + * O_APPEND writes, otherwise we can land up writing at the wrong + * offset. There is still a race, but provided the app is using its + * own file locking, this will make O_APPEND work as expected. + * + */ + +static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + struct file *file = iocb->ki_filp; + + if (file->f_flags & O_APPEND) { + struct dentry *dentry = file->f_dentry; + struct gfs2_inode *ip = GFS2_I(dentry->d_inode); + struct gfs2_holder gh; + int ret; + + ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); + if (ret) + return ret; + gfs2_glock_dq_uninit(&gh); + } + + return generic_file_aio_write(iocb, iov, nr_segs, pos); +} + #ifdef CONFIG_GFS2_FS_LOCKING_DLM /** @@ -711,7 +745,7 @@ const struct file_operations gfs2_file_fops = { .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, - .aio_write = generic_file_aio_write, + .aio_write = gfs2_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open, @@ -741,7 +775,7 @@ const struct file_operations gfs2_file_fops_nolock = { .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, - .aio_write = generic_file_aio_write, + .aio_write = gfs2_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open,