diff options
| -rw-r--r-- | fs/nfs/localio.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c index 647fa19b0479..9c205f8b5e59 100644 --- a/fs/nfs/localio.c +++ b/fs/nfs/localio.c @@ -414,7 +414,7 @@ nfs_local_iters_setup_dio(struct nfs_local_kiocb *iocb, int rw, /* Setup misaligned end? * If so, the end is purposely setup to be issued using buffered IO * before the middle (which will use DIO, if DIO-aligned, with AIO). - * This creates problems if/when the end results in a partial write. + * This creates problems if/when the end results in short read or write. * So must save index and length of end to handle this corner case. */ if (local_dio->end_len) { @@ -580,8 +580,9 @@ static void nfs_local_read_done(struct nfs_local_kiocb *iocb) */ hdr->res.replen = 0; - if (hdr->res.count != hdr->args.count || - hdr->args.offset + hdr->res.count >= i_size_read(file_inode(filp))) + /* nfs_readpage_result() handles short read */ + + if (hdr->args.offset + hdr->res.count >= i_size_read(file_inode(filp))) hdr->res.eof = true; dprintk("%s: read %ld bytes eof %d.\n", __func__, @@ -620,6 +621,7 @@ static void nfs_local_call_read(struct work_struct *work) container_of(work, struct nfs_local_kiocb, work); struct file *filp = iocb->kiocb.ki_filp; const struct cred *save_cred; + bool force_done = false; ssize_t status; int n_iters; @@ -637,7 +639,21 @@ static void nfs_local_call_read(struct work_struct *work) iocb->kiocb.ki_pos = iocb->offset[i]; status = filp->f_op->read_iter(&iocb->kiocb, &iocb->iters[i]); if (status != -EIOCBQUEUED) { - if (nfs_local_pgio_done(iocb, status, false)) { + if (unlikely(status >= 0 && status < iocb->iters[i].count)) { + /* partial read */ + if (i == iocb->end_iter_index) { + /* Must not account DIO partial end, otherwise (due + * to end being issued before middle): the partial + * read accounting in nfs_local_read_done() + * would incorrectly advance hdr->args.offset + */ + status = 0; + } else { + /* Partial read at start or middle, force done */ + force_done = true; + } + } + if (nfs_local_pgio_done(iocb, status, force_done)) { nfs_local_read_iocb_done(iocb); break; } |