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-rw-r--r--fs/fscache/main.c230
1 files changed, 0 insertions, 230 deletions
diff --git a/fs/fscache/main.c b/fs/fscache/main.c
deleted file mode 100644
index 4207f98e405f..000000000000
--- a/fs/fscache/main.c
+++ /dev/null
@@ -1,230 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* General filesystem local caching manager
- *
- * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#define FSCACHE_DEBUG_LEVEL CACHE
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/sched.h>
-#include <linux/completion.h>
-#include <linux/slab.h>
-#include <linux/seq_file.h>
-#define CREATE_TRACE_POINTS
-#include "internal.h"
-
-MODULE_DESCRIPTION("FS Cache Manager");
-MODULE_AUTHOR("Red Hat, Inc.");
-MODULE_LICENSE("GPL");
-
-unsigned fscache_defer_lookup = 1;
-module_param_named(defer_lookup, fscache_defer_lookup, uint,
- S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_defer_lookup,
- "Defer cookie lookup to background thread");
-
-unsigned fscache_defer_create = 1;
-module_param_named(defer_create, fscache_defer_create, uint,
- S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_defer_create,
- "Defer cookie creation to background thread");
-
-unsigned fscache_debug;
-module_param_named(debug, fscache_debug, uint,
- S_IWUSR | S_IRUGO);
-MODULE_PARM_DESC(fscache_debug,
- "FS-Cache debugging mask");
-
-struct kobject *fscache_root;
-struct workqueue_struct *fscache_object_wq;
-struct workqueue_struct *fscache_op_wq;
-
-DEFINE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
-
-/* these values serve as lower bounds, will be adjusted in fscache_init() */
-static unsigned fscache_object_max_active = 4;
-static unsigned fscache_op_max_active = 2;
-
-#ifdef CONFIG_SYSCTL
-static struct ctl_table_header *fscache_sysctl_header;
-
-static int fscache_max_active_sysctl(struct ctl_table *table, int write,
- void *buffer, size_t *lenp, loff_t *ppos)
-{
- struct workqueue_struct **wqp = table->extra1;
- unsigned int *datap = table->data;
- int ret;
-
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
- if (ret == 0)
- workqueue_set_max_active(*wqp, *datap);
- return ret;
-}
-
-static struct ctl_table fscache_sysctls[] = {
- {
- .procname = "object_max_active",
- .data = &fscache_object_max_active,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = fscache_max_active_sysctl,
- .extra1 = &fscache_object_wq,
- },
- {
- .procname = "operation_max_active",
- .data = &fscache_op_max_active,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = fscache_max_active_sysctl,
- .extra1 = &fscache_op_wq,
- },
- {}
-};
-
-static struct ctl_table fscache_sysctls_root[] = {
- {
- .procname = "fscache",
- .mode = 0555,
- .child = fscache_sysctls,
- },
- {}
-};
-#endif
-
-/*
- * Mixing scores (in bits) for (7,20):
- * Input delta: 1-bit 2-bit
- * 1 round: 330.3 9201.6
- * 2 rounds: 1246.4 25475.4
- * 3 rounds: 1907.1 31295.1
- * 4 rounds: 2042.3 31718.6
- * Perfect: 2048 31744
- * (32*64) (32*31/2 * 64)
- */
-#define HASH_MIX(x, y, a) \
- ( x ^= (a), \
- y ^= x, x = rol32(x, 7),\
- x += y, y = rol32(y,20),\
- y *= 9 )
-
-static inline unsigned int fold_hash(unsigned long x, unsigned long y)
-{
- /* Use arch-optimized multiply if one exists */
- return __hash_32(y ^ __hash_32(x));
-}
-
-/*
- * Generate a hash. This is derived from full_name_hash(), but we want to be
- * sure it is arch independent and that it doesn't change as bits of the
- * computed hash value might appear on disk. The caller also guarantees that
- * the hashed data will be a series of aligned 32-bit words.
- */
-unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n)
-{
- unsigned int a, x = 0, y = salt;
-
- for (; n; n--) {
- a = *data++;
- HASH_MIX(x, y, a);
- }
- return fold_hash(x, y);
-}
-
-/*
- * initialise the fs caching module
- */
-static int __init fscache_init(void)
-{
- unsigned int nr_cpus = num_possible_cpus();
- unsigned int cpu;
- int ret;
-
- fscache_object_max_active =
- clamp_val(nr_cpus,
- fscache_object_max_active, WQ_UNBOUND_MAX_ACTIVE);
-
- ret = -ENOMEM;
- fscache_object_wq = alloc_workqueue("fscache_object", WQ_UNBOUND,
- fscache_object_max_active);
- if (!fscache_object_wq)
- goto error_object_wq;
-
- fscache_op_max_active =
- clamp_val(fscache_object_max_active / 2,
- fscache_op_max_active, WQ_UNBOUND_MAX_ACTIVE);
-
- ret = -ENOMEM;
- fscache_op_wq = alloc_workqueue("fscache_operation", WQ_UNBOUND,
- fscache_op_max_active);
- if (!fscache_op_wq)
- goto error_op_wq;
-
- for_each_possible_cpu(cpu)
- init_waitqueue_head(&per_cpu(fscache_object_cong_wait, cpu));
-
- ret = fscache_proc_init();
- if (ret < 0)
- goto error_proc;
-
-#ifdef CONFIG_SYSCTL
- ret = -ENOMEM;
- fscache_sysctl_header = register_sysctl_table(fscache_sysctls_root);
- if (!fscache_sysctl_header)
- goto error_sysctl;
-#endif
-
- fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
- sizeof(struct fscache_cookie),
- 0, 0, NULL);
- if (!fscache_cookie_jar) {
- pr_notice("Failed to allocate a cookie jar\n");
- ret = -ENOMEM;
- goto error_cookie_jar;
- }
-
- fscache_root = kobject_create_and_add("fscache", kernel_kobj);
- if (!fscache_root)
- goto error_kobj;
-
- pr_notice("Loaded\n");
- return 0;
-
-error_kobj:
- kmem_cache_destroy(fscache_cookie_jar);
-error_cookie_jar:
-#ifdef CONFIG_SYSCTL
- unregister_sysctl_table(fscache_sysctl_header);
-error_sysctl:
-#endif
- fscache_proc_cleanup();
-error_proc:
- destroy_workqueue(fscache_op_wq);
-error_op_wq:
- destroy_workqueue(fscache_object_wq);
-error_object_wq:
- return ret;
-}
-
-fs_initcall(fscache_init);
-
-/*
- * clean up on module removal
- */
-static void __exit fscache_exit(void)
-{
- _enter("");
-
- kobject_put(fscache_root);
- kmem_cache_destroy(fscache_cookie_jar);
-#ifdef CONFIG_SYSCTL
- unregister_sysctl_table(fscache_sysctl_header);
-#endif
- fscache_proc_cleanup();
- destroy_workqueue(fscache_op_wq);
- destroy_workqueue(fscache_object_wq);
- pr_notice("Unloaded\n");
-}
-
-module_exit(fscache_exit);