diff --git a/fs/netfs/buffered_read.c b/fs/netfs/buffered_read.c index a8c0d86118c5..a27ed501b6d4 100644 --- a/fs/netfs/buffered_read.c +++ b/fs/netfs/buffered_read.c @@ -156,9 +156,8 @@ static void netfs_read_cache_to_pagecache(struct netfs_io_request *rreq, netfs_cache_read_terminated, subreq); } -static void netfs_queue_read(struct netfs_io_request *rreq, - struct netfs_io_subrequest *subreq, - bool last_subreq) +void netfs_queue_read(struct netfs_io_request *rreq, + struct netfs_io_subrequest *subreq) { struct netfs_io_stream *stream = &rreq->io_streams[0]; @@ -178,11 +177,6 @@ static void netfs_queue_read(struct netfs_io_request *rreq, } } - if (last_subreq) { - smp_wmb(); /* Write lists before ALL_QUEUED. */ - set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); - } - spin_unlock(&rreq->lock); } @@ -233,6 +227,8 @@ static void netfs_read_to_pagecache(struct netfs_io_request *rreq, subreq->start = start; subreq->len = size; + netfs_queue_read(rreq, subreq); + source = netfs_cache_prepare_read(rreq, subreq, rreq->i_size); subreq->source = source; if (source == NETFS_DOWNLOAD_FROM_SERVER) { @@ -253,6 +249,7 @@ static void netfs_read_to_pagecache(struct netfs_io_request *rreq, rreq->debug_id, subreq->debug_index, subreq->len, size, subreq->start, ictx->zero_point, rreq->i_size); + netfs_cancel_read(subreq, ret); break; } subreq->len = len; @@ -261,12 +258,7 @@ static void netfs_read_to_pagecache(struct netfs_io_request *rreq, if (rreq->netfs_ops->prepare_read) { ret = rreq->netfs_ops->prepare_read(subreq); if (ret < 0) { - subreq->error = ret; - /* Not queued - release both refs. */ - netfs_put_subrequest(subreq, - netfs_sreq_trace_put_cancel); - netfs_put_subrequest(subreq, - netfs_sreq_trace_put_cancel); + netfs_cancel_read(subreq, ret); break; } trace_netfs_sreq(subreq, netfs_sreq_trace_prepare); @@ -289,23 +281,23 @@ static void netfs_read_to_pagecache(struct netfs_io_request *rreq, pr_err("Unexpected read source %u\n", source); WARN_ON_ONCE(1); + netfs_cancel_read(subreq, ret); break; issue: slice = netfs_prepare_read_iterator(subreq, ractl); if (slice < 0) { ret = slice; - subreq->error = ret; - trace_netfs_sreq(subreq, netfs_sreq_trace_cancel); - /* Not queued - release both refs. */ - netfs_put_subrequest(subreq, netfs_sreq_trace_put_cancel); - netfs_put_subrequest(subreq, netfs_sreq_trace_put_cancel); + netfs_cancel_read(subreq, ret); break; } - size -= slice; start += slice; + size -= slice; + if (size <= 0) { + smp_wmb(); /* Write lists before ALL_QUEUED. */ + set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); + } - netfs_queue_read(rreq, subreq, size <= 0); netfs_issue_read(rreq, subreq); cond_resched(); } while (size > 0); diff --git a/fs/netfs/direct_read.c b/fs/netfs/direct_read.c index f72e6da88cca..6a8fb0d55e04 100644 --- a/fs/netfs/direct_read.c +++ b/fs/netfs/direct_read.c @@ -45,12 +45,11 @@ static void netfs_prepare_dio_read_iterator(struct netfs_io_subrequest *subreq) * Perform a read to a buffer from the server, slicing up the region to be read * according to the network rsize. */ -static int netfs_dispatch_unbuffered_reads(struct netfs_io_request *rreq) +static void netfs_dispatch_unbuffered_reads(struct netfs_io_request *rreq) { - struct netfs_io_stream *stream = &rreq->io_streams[0]; unsigned long long start = rreq->start; ssize_t size = rreq->len; - int ret = 0; + int ret; do { struct netfs_io_subrequest *subreq; @@ -58,7 +57,10 @@ static int netfs_dispatch_unbuffered_reads(struct netfs_io_request *rreq) subreq = netfs_alloc_subrequest(rreq); if (!subreq) { - ret = -ENOMEM; + /* Stash the error in the request if there's not + * already an error set. + */ + cmpxchg(&rreq->error, 0, -ENOMEM); break; } @@ -66,25 +68,13 @@ static int netfs_dispatch_unbuffered_reads(struct netfs_io_request *rreq) subreq->start = start; subreq->len = size; - __set_bit(NETFS_SREQ_IN_PROGRESS, &subreq->flags); - - spin_lock(&rreq->lock); - list_add_tail(&subreq->rreq_link, &stream->subrequests); - if (list_is_first(&subreq->rreq_link, &stream->subrequests)) { - if (!stream->active) { - stream->collected_to = subreq->start; - /* Store list pointers before active flag */ - smp_store_release(&stream->active, true); - } - } - trace_netfs_sreq(subreq, netfs_sreq_trace_added); - spin_unlock(&rreq->lock); + netfs_queue_read(rreq, subreq); netfs_stat(&netfs_n_rh_download); if (rreq->netfs_ops->prepare_read) { ret = rreq->netfs_ops->prepare_read(subreq); if (ret < 0) { - netfs_put_subrequest(subreq, netfs_sreq_trace_put_cancel); + netfs_cancel_read(subreq, ret); break; } } @@ -113,8 +103,6 @@ static int netfs_dispatch_unbuffered_reads(struct netfs_io_request *rreq) set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); netfs_wake_collector(rreq); } - - return ret; } /* @@ -137,21 +125,17 @@ static ssize_t netfs_unbuffered_read(struct netfs_io_request *rreq, bool sync) // TODO: Use bounce buffer if requested inode_dio_begin(rreq->inode); + netfs_dispatch_unbuffered_reads(rreq); - ret = netfs_dispatch_unbuffered_reads(rreq); - - if (!rreq->submitted) { - netfs_put_request(rreq, netfs_rreq_trace_put_no_submit); - inode_dio_end(rreq->inode); - ret = 0; - goto out; - } + /* The collector will get run, even if we don't manage to submit any + * subreqs, so we shouldn't call inode_dio_end() here. + */ if (sync) ret = netfs_wait_for_read(rreq); else ret = -EIOCBQUEUED; -out: + _leave(" = %zd", ret); return ret; } diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h index d436e20d3418..645996ecfc80 100644 --- a/fs/netfs/internal.h +++ b/fs/netfs/internal.h @@ -23,6 +23,8 @@ /* * buffered_read.c */ +void netfs_queue_read(struct netfs_io_request *rreq, + struct netfs_io_subrequest *subreq); void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error); int netfs_prefetch_for_write(struct file *file, struct folio *folio, size_t offset, size_t len); @@ -108,6 +110,7 @@ static inline void netfs_see_subrequest(struct netfs_io_subrequest *subreq, */ bool netfs_read_collection(struct netfs_io_request *rreq); void netfs_read_collection_worker(struct work_struct *work); +void netfs_cancel_read(struct netfs_io_subrequest *subreq, int error); void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error); /* diff --git a/fs/netfs/read_collect.c b/fs/netfs/read_collect.c index e5f6665b3341..d2d902f46627 100644 --- a/fs/netfs/read_collect.c +++ b/fs/netfs/read_collect.c @@ -575,6 +575,17 @@ void netfs_read_subreq_terminated(struct netfs_io_subrequest *subreq) } EXPORT_SYMBOL(netfs_read_subreq_terminated); +/* + * Cancel a read subrequest due to preparation failure. + */ +void netfs_cancel_read(struct netfs_io_subrequest *subreq, int error) +{ + trace_netfs_sreq(subreq, netfs_sreq_trace_cancel); + subreq->error = error; + __set_bit(NETFS_SREQ_FAILED, &subreq->flags); + netfs_read_subreq_terminated(subreq); +} + /* * Handle termination of a read from the cache. */ diff --git a/fs/netfs/read_single.c b/fs/netfs/read_single.c index d0e23bc42445..8833550d2eb6 100644 --- a/fs/netfs/read_single.c +++ b/fs/netfs/read_single.c @@ -89,7 +89,6 @@ static void netfs_single_read_cache(struct netfs_io_request *rreq, */ static int netfs_single_dispatch_read(struct netfs_io_request *rreq) { - struct netfs_io_stream *stream = &rreq->io_streams[0]; struct netfs_io_subrequest *subreq; int ret = 0; @@ -102,14 +101,7 @@ static int netfs_single_dispatch_read(struct netfs_io_request *rreq) subreq->len = rreq->len; subreq->io_iter = rreq->buffer.iter; - __set_bit(NETFS_SREQ_IN_PROGRESS, &subreq->flags); - - spin_lock(&rreq->lock); - list_add_tail(&subreq->rreq_link, &stream->subrequests); - trace_netfs_sreq(subreq, netfs_sreq_trace_added); - /* Store list pointers before active flag */ - smp_store_release(&stream->active, true); - spin_unlock(&rreq->lock); + netfs_queue_read(rreq, subreq); netfs_single_cache_prepare_read(rreq, subreq); switch (subreq->source) { @@ -121,10 +113,14 @@ static int netfs_single_dispatch_read(struct netfs_io_request *rreq) goto cancel; } + smp_wmb(); /* Write lists before ALL_QUEUED. */ + set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); rreq->netfs_ops->issue_read(subreq); rreq->submitted += subreq->len; break; case NETFS_READ_FROM_CACHE: + smp_wmb(); /* Write lists before ALL_QUEUED. */ + set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); trace_netfs_sreq(subreq, netfs_sreq_trace_submit); netfs_single_read_cache(rreq, subreq); rreq->submitted += subreq->len; @@ -134,14 +130,15 @@ static int netfs_single_dispatch_read(struct netfs_io_request *rreq) pr_warn("Unexpected single-read source %u\n", subreq->source); WARN_ON_ONCE(true); ret = -EIO; - break; + goto cancel; } - smp_wmb(); /* Write lists before ALL_QUEUED. */ - set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); return ret; cancel: - netfs_put_subrequest(subreq, netfs_sreq_trace_put_cancel); + netfs_cancel_read(subreq, ret); + smp_wmb(); /* Write lists before ALL_QUEUED. */ + set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags); + netfs_wake_collector(rreq); return ret; }