| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* Miscellaneous bits for the netfs support library. |
| * |
| * Copyright (C) 2022 Red Hat, Inc. All Rights Reserved. |
| * Written by David Howells (dhowells@redhat.com) |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/export.h> |
| #include <linux/mempool.h> |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| #include "internal.h" |
| #define CREATE_TRACE_POINTS |
| #include <trace/events/netfs.h> |
| |
| MODULE_DESCRIPTION("Network fs support"); |
| MODULE_AUTHOR("Red Hat, Inc."); |
| MODULE_LICENSE("GPL"); |
| |
| EXPORT_TRACEPOINT_SYMBOL(netfs_sreq); |
| |
| unsigned netfs_debug; |
| module_param_named(debug, netfs_debug, uint, S_IWUSR | S_IRUGO); |
| MODULE_PARM_DESC(netfs_debug, "Netfs support debugging mask"); |
| |
| static struct kmem_cache *netfs_request_slab; |
| static struct kmem_cache *netfs_subrequest_slab; |
| mempool_t netfs_request_pool; |
| mempool_t netfs_subrequest_pool; |
| |
| #ifdef CONFIG_PROC_FS |
| LIST_HEAD(netfs_io_requests); |
| DEFINE_SPINLOCK(netfs_proc_lock); |
| |
| static const char *netfs_origins[nr__netfs_io_origin] = { |
| [NETFS_READAHEAD] = "RA", |
| [NETFS_READPAGE] = "RP", |
| [NETFS_READ_FOR_WRITE] = "RW", |
| [NETFS_COPY_TO_CACHE] = "CC", |
| [NETFS_WRITEBACK] = "WB", |
| [NETFS_WRITETHROUGH] = "WT", |
| [NETFS_UNBUFFERED_WRITE] = "UW", |
| [NETFS_DIO_READ] = "DR", |
| [NETFS_DIO_WRITE] = "DW", |
| }; |
| |
| /* |
| * Generate a list of I/O requests in /proc/fs/netfs/requests |
| */ |
| static int netfs_requests_seq_show(struct seq_file *m, void *v) |
| { |
| struct netfs_io_request *rreq; |
| |
| if (v == &netfs_io_requests) { |
| seq_puts(m, |
| "REQUEST OR REF FL ERR OPS COVERAGE\n" |
| "======== == === == ==== === =========\n" |
| ); |
| return 0; |
| } |
| |
| rreq = list_entry(v, struct netfs_io_request, proc_link); |
| seq_printf(m, |
| "%08x %s %3d %2lx %4d %3d @%04llx %llx/%llx", |
| rreq->debug_id, |
| netfs_origins[rreq->origin], |
| refcount_read(&rreq->ref), |
| rreq->flags, |
| rreq->error, |
| atomic_read(&rreq->nr_outstanding), |
| rreq->start, rreq->submitted, rreq->len); |
| seq_putc(m, '\n'); |
| return 0; |
| } |
| |
| static void *netfs_requests_seq_start(struct seq_file *m, loff_t *_pos) |
| __acquires(rcu) |
| { |
| rcu_read_lock(); |
| return seq_list_start_head(&netfs_io_requests, *_pos); |
| } |
| |
| static void *netfs_requests_seq_next(struct seq_file *m, void *v, loff_t *_pos) |
| { |
| return seq_list_next(v, &netfs_io_requests, _pos); |
| } |
| |
| static void netfs_requests_seq_stop(struct seq_file *m, void *v) |
| __releases(rcu) |
| { |
| rcu_read_unlock(); |
| } |
| |
| static const struct seq_operations netfs_requests_seq_ops = { |
| .start = netfs_requests_seq_start, |
| .next = netfs_requests_seq_next, |
| .stop = netfs_requests_seq_stop, |
| .show = netfs_requests_seq_show, |
| }; |
| #endif /* CONFIG_PROC_FS */ |
| |
| static int __init netfs_init(void) |
| { |
| int ret = -ENOMEM; |
| |
| netfs_request_slab = kmem_cache_create("netfs_request", |
| sizeof(struct netfs_io_request), 0, |
| SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, |
| NULL); |
| if (!netfs_request_slab) |
| goto error_req; |
| |
| if (mempool_init_slab_pool(&netfs_request_pool, 100, netfs_request_slab) < 0) |
| goto error_reqpool; |
| |
| netfs_subrequest_slab = kmem_cache_create("netfs_subrequest", |
| sizeof(struct netfs_io_subrequest), 0, |
| SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, |
| NULL); |
| if (!netfs_subrequest_slab) |
| goto error_subreq; |
| |
| if (mempool_init_slab_pool(&netfs_subrequest_pool, 100, netfs_subrequest_slab) < 0) |
| goto error_subreqpool; |
| |
| if (!proc_mkdir("fs/netfs", NULL)) |
| goto error_proc; |
| if (!proc_create_seq("fs/netfs/requests", S_IFREG | 0444, NULL, |
| &netfs_requests_seq_ops)) |
| goto error_procfile; |
| #ifdef CONFIG_FSCACHE_STATS |
| if (!proc_create_single("fs/netfs/stats", S_IFREG | 0444, NULL, |
| netfs_stats_show)) |
| goto error_procfile; |
| #endif |
| |
| ret = fscache_init(); |
| if (ret < 0) |
| goto error_fscache; |
| return 0; |
| |
| error_fscache: |
| error_procfile: |
| remove_proc_entry("fs/netfs", NULL); |
| error_proc: |
| mempool_exit(&netfs_subrequest_pool); |
| error_subreqpool: |
| kmem_cache_destroy(netfs_subrequest_slab); |
| error_subreq: |
| mempool_exit(&netfs_request_pool); |
| error_reqpool: |
| kmem_cache_destroy(netfs_request_slab); |
| error_req: |
| return ret; |
| } |
| fs_initcall(netfs_init); |
| |
| static void __exit netfs_exit(void) |
| { |
| fscache_exit(); |
| remove_proc_entry("fs/netfs", NULL); |
| mempool_exit(&netfs_subrequest_pool); |
| kmem_cache_destroy(netfs_subrequest_slab); |
| mempool_exit(&netfs_request_pool); |
| kmem_cache_destroy(netfs_request_slab); |
| } |
| module_exit(netfs_exit); |