diff options
Diffstat (limited to 'fs/netfs/io.c')
-rw-r--r-- | fs/netfs/io.c | 69 |
1 files changed, 50 insertions, 19 deletions
diff --git a/fs/netfs/io.c b/fs/netfs/io.c index 7f753380e047..e9d408e211b8 100644 --- a/fs/netfs/io.c +++ b/fs/netfs/io.c @@ -21,12 +21,7 @@ */ static void netfs_clear_unread(struct netfs_io_subrequest *subreq) { - struct iov_iter iter; - - iov_iter_xarray(&iter, ITER_DEST, &subreq->rreq->mapping->i_pages, - subreq->start + subreq->transferred, - subreq->len - subreq->transferred); - iov_iter_zero(iov_iter_count(&iter), &iter); + iov_iter_zero(iov_iter_count(&subreq->io_iter), &subreq->io_iter); } static void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error, @@ -46,14 +41,9 @@ static void netfs_read_from_cache(struct netfs_io_request *rreq, enum netfs_read_from_hole read_hole) { struct netfs_cache_resources *cres = &rreq->cache_resources; - struct iov_iter iter; netfs_stat(&netfs_n_rh_read); - iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages, - subreq->start + subreq->transferred, - subreq->len - subreq->transferred); - - cres->ops->read(cres, subreq->start, &iter, read_hole, + cres->ops->read(cres, subreq->start, &subreq->io_iter, read_hole, netfs_cache_read_terminated, subreq); } @@ -88,6 +78,11 @@ 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) + 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, + subreq->transferred, subreq->flags); rreq->netfs_ops->issue_read(subreq); } @@ -260,6 +255,30 @@ static void netfs_rreq_short_read(struct netfs_io_request *rreq, } /* + * Reset the subrequest iterator prior to resubmission. + */ +static void netfs_reset_subreq_iter(struct netfs_io_request *rreq, + struct netfs_io_subrequest *subreq) +{ + size_t remaining = subreq->len - subreq->transferred; + size_t count = iov_iter_count(&subreq->io_iter); + + if (count == remaining) + return; + + _debug("R=%08x[%u] ITER RESUB-MISMATCH %zx != %zx-%zx-%llx %x\n", + rreq->debug_id, subreq->debug_index, + iov_iter_count(&subreq->io_iter), subreq->transferred, + subreq->len, rreq->i_size, + subreq->io_iter.iter_type); + + if (count < remaining) + iov_iter_revert(&subreq->io_iter, remaining - count); + else + iov_iter_advance(&subreq->io_iter, count - remaining); +} + +/* * Resubmit any short or failed operations. Returns true if we got the rreq * ref back. */ @@ -287,6 +306,7 @@ static bool netfs_rreq_perform_resubmissions(struct netfs_io_request *rreq) trace_netfs_sreq(subreq, netfs_sreq_trace_download_instead); netfs_get_subrequest(subreq, netfs_sreq_trace_get_resubmit); atomic_inc(&rreq->nr_outstanding); + netfs_reset_subreq_iter(rreq, subreq); netfs_read_from_server(rreq, subreq); } else if (test_bit(NETFS_SREQ_SHORT_IO, &subreq->flags)) { netfs_rreq_short_read(rreq, subreq); @@ -399,9 +419,9 @@ void netfs_subreq_terminated(struct netfs_io_subrequest *subreq, struct netfs_io_request *rreq = subreq->rreq; int u; - _enter("[%u]{%llx,%lx},%zd", - subreq->debug_index, subreq->start, subreq->flags, - transferred_or_error); + _enter("R=%x[%x]{%llx,%lx},%zd", + rreq->debug_id, subreq->debug_index, + subreq->start, subreq->flags, transferred_or_error); switch (subreq->source) { case NETFS_READ_FROM_CACHE: @@ -501,7 +521,8 @@ static enum netfs_io_source netfs_cache_prepare_read(struct netfs_io_subrequest */ static enum netfs_io_source netfs_rreq_prepare_read(struct netfs_io_request *rreq, - struct netfs_io_subrequest *subreq) + struct netfs_io_subrequest *subreq, + struct iov_iter *io_iter) { enum netfs_io_source source; @@ -528,9 +549,14 @@ netfs_rreq_prepare_read(struct netfs_io_request *rreq, } } - if (WARN_ON(subreq->len == 0)) + if (WARN_ON(subreq->len == 0)) { source = NETFS_INVALID_READ; + goto out; + } + subreq->io_iter = *io_iter; + iov_iter_truncate(&subreq->io_iter, subreq->len); + iov_iter_advance(io_iter, subreq->len); out: subreq->source = source; trace_netfs_sreq(subreq, netfs_sreq_trace_prepare); @@ -541,6 +567,7 @@ out: * Slice off a piece of a read request and submit an I/O request for it. */ static bool netfs_rreq_submit_slice(struct netfs_io_request *rreq, + struct iov_iter *io_iter, unsigned int *_debug_index) { struct netfs_io_subrequest *subreq; @@ -565,7 +592,7 @@ static bool netfs_rreq_submit_slice(struct netfs_io_request *rreq, * (the starts must coincide), in which case, we go around the loop * again and ask it to download the next piece. */ - source = netfs_rreq_prepare_read(rreq, subreq); + source = netfs_rreq_prepare_read(rreq, subreq, io_iter); if (source == NETFS_INVALID_READ) goto subreq_failed; @@ -603,6 +630,7 @@ subreq_failed: */ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) { + struct iov_iter io_iter; unsigned int debug_index = 0; int ret; @@ -615,6 +643,8 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) return -EIO; } + rreq->io_iter = rreq->iter; + INIT_WORK(&rreq->work, netfs_rreq_work); if (sync) @@ -624,8 +654,9 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool sync) * want and submit each one. */ atomic_set(&rreq->nr_outstanding, 1); + io_iter = rreq->io_iter; do { - if (!netfs_rreq_submit_slice(rreq, &debug_index)) + if (!netfs_rreq_submit_slice(rreq, &io_iter, &debug_index)) break; } while (rreq->submitted < rreq->len); |