diff options
Diffstat (limited to 'fs/netfs/io.c')
-rw-r--r-- | fs/netfs/io.c | 83 |
1 files changed, 75 insertions, 8 deletions
diff --git a/fs/netfs/io.c b/fs/netfs/io.c index 774aef6ea4cb..c972415c8aad 100644 --- a/fs/netfs/io.c +++ b/fs/netfs/io.c @@ -78,7 +78,9 @@ static void netfs_read_from_server(struct netfs_io_request *rreq, struct netfs_io_subrequest *subreq) { netfs_stat(&netfs_n_rh_download); - if (iov_iter_count(&subreq->io_iter) != subreq->len - subreq->transferred) + + if (rreq->origin != NETFS_DIO_READ && + iov_iter_count(&subreq->io_iter) != subreq->len - subreq->transferred) pr_warn("R=%08x[%u] ITER PRE-MISMATCH %zx != %zx-%zx %lx\n", rreq->debug_id, subreq->debug_index, iov_iter_count(&subreq->io_iter), subreq->len, @@ -342,6 +344,43 @@ static void netfs_rreq_is_still_valid(struct netfs_io_request *rreq) } /* + * Determine how much we can admit to having read from a DIO read. + */ +static void netfs_rreq_assess_dio(struct netfs_io_request *rreq) +{ + struct netfs_io_subrequest *subreq; + unsigned int i; + size_t transferred = 0; + + for (i = 0; i < rreq->direct_bv_count; i++) + flush_dcache_page(rreq->direct_bv[i].bv_page); + + list_for_each_entry(subreq, &rreq->subrequests, rreq_link) { + if (subreq->error || subreq->transferred == 0) + break; + transferred += subreq->transferred; + if (subreq->transferred < subreq->len) + break; + } + + for (i = 0; i < rreq->direct_bv_count; i++) + flush_dcache_page(rreq->direct_bv[i].bv_page); + + rreq->transferred = transferred; + task_io_account_read(transferred); + + if (rreq->iocb) { + rreq->iocb->ki_pos += transferred; + if (rreq->iocb->ki_complete) + rreq->iocb->ki_complete( + rreq->iocb, rreq->error ? rreq->error : transferred); + } + if (rreq->netfs_ops->done) + rreq->netfs_ops->done(rreq); + inode_dio_end(rreq->inode); +} + +/* * Assess the state of a read request and decide what to do next. * * Note that we could be in an ordinary kernel thread, on a workqueue or in @@ -361,7 +400,10 @@ again: return; } - netfs_rreq_unlock_folios(rreq); + if (rreq->origin != NETFS_DIO_READ) + netfs_rreq_unlock_folios(rreq); + else + netfs_rreq_assess_dio(rreq); trace_netfs_rreq(rreq, netfs_rreq_trace_wake_ip); clear_bit_unlock(NETFS_RREQ_IN_PROGRESS, &rreq->flags); @@ -526,14 +568,16 @@ netfs_rreq_prepare_read(struct netfs_io_request *rreq, struct netfs_io_subrequest *subreq, struct iov_iter *io_iter) { - enum netfs_io_source source; + enum netfs_io_source source = NETFS_DOWNLOAD_FROM_SERVER; size_t lsize; _enter("%llx-%llx,%llx", subreq->start, subreq->start + subreq->len, rreq->i_size); - source = netfs_cache_prepare_read(subreq, rreq->i_size); - if (source == NETFS_INVALID_READ) - goto out; + if (rreq->origin != NETFS_DIO_READ) { + source = netfs_cache_prepare_read(subreq, rreq->i_size); + if (source == NETFS_INVALID_READ) + goto out; + } if (source == NETFS_DOWNLOAD_FROM_SERVER) { /* Call out to the netfs to let it shrink the request to fit @@ -544,6 +588,8 @@ netfs_rreq_prepare_read(struct netfs_io_request *rreq, */ if (subreq->len > rreq->i_size - subreq->start) subreq->len = rreq->i_size - subreq->start; + if (rreq->rsize && subreq->len > rreq->rsize) + subreq->len = rreq->rsize; if (rreq->netfs_ops->clamp_length && !rreq->netfs_ops->clamp_length(subreq)) { @@ -662,6 +708,10 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) return -EIO; } + if (rreq->origin == NETFS_DIO_READ) + inode_dio_begin(rreq->inode); + + // TODO: Use bounce buffer if requested rreq->io_iter = rreq->iter; INIT_WORK(&rreq->work, netfs_rreq_work); @@ -673,11 +723,25 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) atomic_set(&rreq->nr_outstanding, 1); io_iter = rreq->io_iter; do { + _debug("submit %llx + %zx >= %llx", + rreq->start, rreq->submitted, rreq->i_size); + if (rreq->origin == NETFS_DIO_READ && + rreq->start + rreq->submitted >= rreq->i_size) + break; if (!netfs_rreq_submit_slice(rreq, &io_iter, &debug_index)) break; + if (test_bit(NETFS_RREQ_BLOCKED, &rreq->flags) && + test_bit(NETFS_RREQ_NONBLOCK, &rreq->flags)) + break; } while (rreq->submitted < rreq->len); + if (!rreq->submitted) { + netfs_put_request(rreq, false, netfs_rreq_trace_put_no_submit); + ret = 0; + goto out; + } + if (sync) { /* Keep nr_outstanding incremented so that the ref always * belongs to us, and the service code isn't punted off to a @@ -694,7 +758,8 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) TASK_UNINTERRUPTIBLE); ret = rreq->error; - if (ret == 0 && rreq->submitted < rreq->len) { + if (ret == 0 && rreq->submitted < rreq->len && + rreq->origin != NETFS_DIO_READ) { trace_netfs_failure(rreq, NULL, ret, netfs_fail_short_read); ret = -EIO; } @@ -702,7 +767,9 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) /* If we decrement nr_outstanding to 0, the ref belongs to us. */ if (atomic_dec_and_test(&rreq->nr_outstanding)) netfs_rreq_assess(rreq, false); - ret = 0; + ret = -EIOCBQUEUED; } + +out: return ret; } |