diff options
Diffstat (limited to 'fs/netfs/objects.c')
| -rw-r--r-- | fs/netfs/objects.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c new file mode 100644 index 000000000..e17cdf53f --- /dev/null +++ b/fs/netfs/objects.c @@ -0,0 +1,160 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Object lifetime handling and tracing. + * + * Copyright (C) 2022 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <linux/slab.h> +#include "internal.h" + +/* + * Allocate an I/O request and initialise it. + */ +struct netfs_io_request *netfs_alloc_request(struct address_space *mapping, + struct file *file, + loff_t start, size_t len, + enum netfs_io_origin origin) +{ + static atomic_t debug_ids; + struct inode *inode = file ? file_inode(file) : mapping->host; + struct netfs_inode *ctx = netfs_inode(inode); + struct netfs_io_request *rreq; + int ret; + + rreq = kzalloc(sizeof(struct netfs_io_request), GFP_KERNEL); + if (!rreq) + return ERR_PTR(-ENOMEM); + + rreq->start = start; + rreq->len = len; + rreq->origin = origin; + rreq->netfs_ops = ctx->ops; + rreq->mapping = mapping; + rreq->inode = inode; + rreq->i_size = i_size_read(inode); + rreq->debug_id = atomic_inc_return(&debug_ids); + INIT_LIST_HEAD(&rreq->subrequests); + refcount_set(&rreq->ref, 1); + __set_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags); + if (rreq->netfs_ops->init_request) { + ret = rreq->netfs_ops->init_request(rreq, file); + if (ret < 0) { + kfree(rreq); + return ERR_PTR(ret); + } + } + + netfs_stat(&netfs_n_rh_rreq); + return rreq; +} + +void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what) +{ + int r; + + __refcount_inc(&rreq->ref, &r); + trace_netfs_rreq_ref(rreq->debug_id, r + 1, what); +} + +void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async) +{ + struct netfs_io_subrequest *subreq; + + while (!list_empty(&rreq->subrequests)) { + subreq = list_first_entry(&rreq->subrequests, + struct netfs_io_subrequest, rreq_link); + list_del(&subreq->rreq_link); + netfs_put_subrequest(subreq, was_async, + netfs_sreq_trace_put_clear); + } +} + +static void netfs_free_request(struct work_struct *work) +{ + struct netfs_io_request *rreq = + container_of(work, struct netfs_io_request, work); + + trace_netfs_rreq(rreq, netfs_rreq_trace_free); + netfs_clear_subrequests(rreq, false); + if (rreq->netfs_ops->free_request) + rreq->netfs_ops->free_request(rreq); + if (rreq->cache_resources.ops) + rreq->cache_resources.ops->end_operation(&rreq->cache_resources); + kfree(rreq); + netfs_stat_d(&netfs_n_rh_rreq); +} + +void netfs_put_request(struct netfs_io_request *rreq, bool was_async, + enum netfs_rreq_ref_trace what) +{ + unsigned int debug_id = rreq->debug_id; + bool dead; + int r; + + dead = __refcount_dec_and_test(&rreq->ref, &r); + trace_netfs_rreq_ref(debug_id, r - 1, what); + if (dead) { + if (was_async) { + rreq->work.func = netfs_free_request; + if (!queue_work(system_unbound_wq, &rreq->work)) + BUG(); + } else { + netfs_free_request(&rreq->work); + } + } +} + +/* + * Allocate and partially initialise an I/O request structure. + */ +struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq) +{ + struct netfs_io_subrequest *subreq; + + subreq = kzalloc(sizeof(struct netfs_io_subrequest), GFP_KERNEL); + if (subreq) { + INIT_LIST_HEAD(&subreq->rreq_link); + refcount_set(&subreq->ref, 2); + subreq->rreq = rreq; + netfs_get_request(rreq, netfs_rreq_trace_get_subreq); + netfs_stat(&netfs_n_rh_sreq); + } + + return subreq; +} + +void netfs_get_subrequest(struct netfs_io_subrequest *subreq, + enum netfs_sreq_ref_trace what) +{ + int r; + + __refcount_inc(&subreq->ref, &r); + trace_netfs_sreq_ref(subreq->rreq->debug_id, subreq->debug_index, r + 1, + what); +} + +static void netfs_free_subrequest(struct netfs_io_subrequest *subreq, + bool was_async) +{ + struct netfs_io_request *rreq = subreq->rreq; + + trace_netfs_sreq(subreq, netfs_sreq_trace_free); + kfree(subreq); + netfs_stat_d(&netfs_n_rh_sreq); + netfs_put_request(rreq, was_async, netfs_rreq_trace_put_subreq); +} + +void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async, + enum netfs_sreq_ref_trace what) +{ + unsigned int debug_index = subreq->debug_index; + unsigned int debug_id = subreq->rreq->debug_id; + bool dead; + int r; + + dead = __refcount_dec_and_test(&subreq->ref, &r); + trace_netfs_sreq_ref(debug_id, debug_index, r - 1, what); + if (dead) + netfs_free_subrequest(subreq, was_async); +} |