diff options
Diffstat (limited to 'fs/direct-io.c')
| -rw-r--r-- | fs/direct-io.c | 94 |
1 files changed, 42 insertions, 52 deletions
diff --git a/fs/direct-io.c b/fs/direct-io.c index 45d34d8..b57b671 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -210,19 +210,46 @@ static struct page *dio_get_page(struct dio *dio) return dio->pages[dio->head++]; } -/* - * Called when all DIO BIO I/O has been completed - let the filesystem - * know, if it registered an interest earlier via get_block. Pass the - * private field of the map buffer_head so that filesystems can use it - * to hold additional state between get_block calls and dio_complete. +/** + * dio_complete() - called when all DIO BIO I/O has been completed + * @offset: the byte offset in the file of the completed operation + * + * This releases locks as dictated by the locking type, lets interested parties + * know that a DIO operation has completed, and calculates the resulting return + * code for the operation. + * + * It lets the filesystem know if it registered an interest earlier via + * get_block. Pass the private field of the map buffer_head so that + * filesystems can use it to hold additional state between get_block calls and + * dio_complete. */ -static void dio_complete(struct dio *dio, loff_t offset, ssize_t bytes) +static int dio_complete(struct dio *dio, loff_t offset, int ret) { + ssize_t transferred = 0; + + if (dio->result) { + transferred = dio->result; + + /* Check for short read case */ + if ((dio->rw == READ) && ((offset + transferred) > dio->i_size)) + transferred = dio->i_size - offset; + } + if (dio->end_io && dio->result) - dio->end_io(dio->iocb, offset, bytes, dio->map_bh.b_private); + dio->end_io(dio->iocb, offset, transferred, + dio->map_bh.b_private); if (dio->lock_type == DIO_LOCKING) /* lockdep: non-owner release */ up_read_non_owner(&dio->inode->i_alloc_sem); + + if (ret == 0) + ret = dio->page_errors; + if (ret == 0) + ret = dio->io_error; + if (ret == 0) + ret = transferred; + + return ret; } /* @@ -236,8 +263,7 @@ static void finished_one_bio(struct dio *dio) spin_lock_irqsave(&dio->bio_lock, flags); if (dio->bio_count == 1) { if (dio->is_async) { - ssize_t transferred; - loff_t offset; + int ret; /* * Last reference to the dio is going away. @@ -245,24 +271,12 @@ static void finished_one_bio(struct dio *dio) */ spin_unlock_irqrestore(&dio->bio_lock, flags); - /* Check for short read case */ - transferred = dio->result; - offset = dio->iocb->ki_pos; - - if ((dio->rw == READ) && - ((offset + transferred) > dio->i_size)) - transferred = dio->i_size - offset; - - /* check for error in completion path */ - if (dio->io_error) - transferred = dio->io_error; - - dio_complete(dio, offset, transferred); + ret = dio_complete(dio, dio->iocb->ki_pos, 0); /* Complete AIO later if falling back to buffered i/o */ if (dio->result == dio->size || ((dio->rw == READ) && dio->result)) { - aio_complete(dio->iocb, transferred, 0); + aio_complete(dio->iocb, ret, 0); kfree(dio); return; } else { @@ -434,10 +448,8 @@ static int dio_bio_complete(struct dio *dio, struct bio *bio) /* * Wait on and process all in-flight BIOs. */ -static int dio_await_completion(struct dio *dio) +static void dio_await_completion(struct dio *dio) { - int ret = 0; - if (dio->bio) dio_bio_submit(dio); @@ -448,13 +460,9 @@ static int dio_await_completion(struct dio *dio) */ while (dio->bio_count) { struct bio *bio = dio_await_one(dio); - int ret2; - - ret2 = dio_bio_complete(dio, bio); - if (ret == 0) - ret = ret2; + /* io errors are propogated through dio->io_error */ + dio_bio_complete(dio, bio); } - return ret; } /* @@ -1127,28 +1135,10 @@ direct_io_worker(int rw, struct kiocb *iocb, struct inode *inode, kfree(dio); } } else { - ssize_t transferred = 0; - finished_one_bio(dio); - ret2 = dio_await_completion(dio); - if (ret == 0) - ret = ret2; - if (ret == 0) - ret = dio->page_errors; - if (dio->result) { - loff_t i_size = i_size_read(inode); + dio_await_completion(dio); - transferred = dio->result; - /* - * Adjust the return value if the read crossed a - * non-block-aligned EOF. - */ - if (rw == READ && (offset + transferred > i_size)) - transferred = i_size - offset; - } - dio_complete(dio, offset, transferred); - if (ret == 0) - ret = transferred; + ret = dio_complete(dio, offset, ret); /* We could have also come here on an AIO file extend */ if (!is_sync_kiocb(iocb) && (rw & WRITE) && |