From 06b3db1b9bccdc8c2c743122a89745279e5ecc46 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:36 +0100 Subject: FS-Cache: Add main configuration option, module entry points and debugging Add the main configuration option, allowing FS-Cache to be selected; the module entry and exit functions and the debugging stuff used by these patches. The two configuration options added are: CONFIG_FSCACHE CONFIG_FSCACHE_DEBUG The first enables the facility, and the second makes the debugging statements enableable through the "debug" module parameter. The value of this parameter is a bitmask as described in: Documentation/filesystems/caching/fscache.txt The module can be loaded at this point, but all it will do at this point in the patch series is to start up the slow work facility and shut it down again. Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- fs/fscache/main.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 fs/fscache/main.c (limited to 'fs/fscache/main.c') diff --git a/fs/fscache/main.c b/fs/fscache/main.c new file mode 100644 index 000000000000..76f7c69079c0 --- /dev/null +++ b/fs/fscache/main.c @@ -0,0 +1,75 @@ +/* General filesystem local caching manager + * + * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#define FSCACHE_DEBUG_LEVEL CACHE +#include +#include +#include +#include +#include +#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; + +/* + * initialise the fs caching module + */ +static int __init fscache_init(void) +{ + int ret; + + ret = slow_work_register_user(); + if (ret < 0) + goto error_slow_work; + + printk(KERN_NOTICE "FS-Cache: Loaded\n"); + return 0; + +error_slow_work: + return ret; +} + +fs_initcall(fscache_init); + +/* + * clean up on module removal + */ +static void __exit fscache_exit(void) +{ + _enter(""); + + slow_work_unregister_user(); + printk(KERN_NOTICE "FS-Cache: Unloaded\n"); +} + +module_exit(fscache_exit); -- cgit v1.2.2 From 7394daa8c61dfda4baa687f133748fa0b599b017 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:37 +0100 Subject: FS-Cache: Add use of /proc and presentation of statistics Make FS-Cache create its /proc interface and present various statistical information through it. Also provide the functions for updating this information. These features are enabled by: CONFIG_FSCACHE_PROC CONFIG_FSCACHE_STATS CONFIG_FSCACHE_HISTOGRAM The /proc directory for FS-Cache is also exported so that caching modules can add their own statistics there too. The FS-Cache module is loadable at this point, and the statistics files can be examined by userspace: cat /proc/fs/fscache/stats cat /proc/fs/fscache/histogram Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- fs/fscache/main.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs/fscache/main.c') diff --git a/fs/fscache/main.c b/fs/fscache/main.c index 76f7c69079c0..7c734b7fb18e 100644 --- a/fs/fscache/main.c +++ b/fs/fscache/main.c @@ -52,9 +52,15 @@ static int __init fscache_init(void) if (ret < 0) goto error_slow_work; + ret = fscache_proc_init(); + if (ret < 0) + goto error_proc; + printk(KERN_NOTICE "FS-Cache: Loaded\n"); return 0; +error_proc: + slow_work_unregister_user(); error_slow_work: return ret; } @@ -68,6 +74,7 @@ static void __exit fscache_exit(void) { _enter(""); + fscache_proc_cleanup(); slow_work_unregister_user(); printk(KERN_NOTICE "FS-Cache: Unloaded\n"); } -- cgit v1.2.2 From 4c515dd47ab41be3f89e757d441661795470b376 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:37 +0100 Subject: FS-Cache: Add cache management Implement the entry points by which a cache backend may initialise, add, declare an error upon and withdraw a cache. Further, an object is created in sysfs under which each cache added will get an object created: /sys/fs/fscache// All of this is described in Documentation/filesystems/caching/backend-api.txt added by a previous patch. Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- fs/fscache/main.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs/fscache/main.c') diff --git a/fs/fscache/main.c b/fs/fscache/main.c index 7c734b7fb18e..c2f3e637725d 100644 --- a/fs/fscache/main.c +++ b/fs/fscache/main.c @@ -56,9 +56,15 @@ static int __init fscache_init(void) if (ret < 0) goto error_proc; + fscache_root = kobject_create_and_add("fscache", kernel_kobj); + if (!fscache_root) + goto error_kobj; + printk(KERN_NOTICE "FS-Cache: Loaded\n"); return 0; +error_kobj: + fscache_proc_cleanup(); error_proc: slow_work_unregister_user(); error_slow_work: @@ -74,6 +80,7 @@ static void __exit fscache_exit(void) { _enter(""); + kobject_put(fscache_root); fscache_proc_cleanup(); slow_work_unregister_user(); printk(KERN_NOTICE "FS-Cache: Unloaded\n"); -- cgit v1.2.2 From 955d00917f0c094e0f2fb88df967e980ab66b8ca Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:38 +0100 Subject: FS-Cache: Provide a slab for cookie allocation Provide a slab from which can be allocated the FS-Cache cookies that will be presented to the netfs. Also provide a slab constructor and a function to recursively discard a cookie and its ancestor chain. Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- fs/fscache/main.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'fs/fscache/main.c') diff --git a/fs/fscache/main.c b/fs/fscache/main.c index c2f3e637725d..48b79d2deac1 100644 --- a/fs/fscache/main.c +++ b/fs/fscache/main.c @@ -56,6 +56,18 @@ static int __init fscache_init(void) if (ret < 0) goto error_proc; + fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar", + sizeof(struct fscache_cookie), + 0, + 0, + fscache_cookie_init_once); + if (!fscache_cookie_jar) { + printk(KERN_NOTICE + "FS-Cache: 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; @@ -64,6 +76,8 @@ static int __init fscache_init(void) return 0; error_kobj: + kmem_cache_destroy(fscache_cookie_jar); +error_cookie_jar: fscache_proc_cleanup(); error_proc: slow_work_unregister_user(); @@ -81,6 +95,7 @@ static void __exit fscache_exit(void) _enter(""); kobject_put(fscache_root); + kmem_cache_destroy(fscache_cookie_jar); fscache_proc_cleanup(); slow_work_unregister_user(); printk(KERN_NOTICE "FS-Cache: Unloaded\n"); -- cgit v1.2.2 From 2868cbea72dc89ae0eb17693596b1dedaafff1c5 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:38 +0100 Subject: FS-Cache: Bit waiting helpers Add helpers for use with wait_on_bit(). Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- fs/fscache/main.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'fs/fscache/main.c') diff --git a/fs/fscache/main.c b/fs/fscache/main.c index 48b79d2deac1..4de41b597499 100644 --- a/fs/fscache/main.c +++ b/fs/fscache/main.c @@ -102,3 +102,23 @@ static void __exit fscache_exit(void) } module_exit(fscache_exit); + +/* + * wait_on_bit() sleep function for uninterruptible waiting + */ +int fscache_wait_bit(void *flags) +{ + schedule(); + return 0; +} +EXPORT_SYMBOL(fscache_wait_bit); + +/* + * wait_on_bit() sleep function for interruptible waiting + */ +int fscache_wait_bit_interruptible(void *flags) +{ + schedule(); + return signal_pending(current); +} +EXPORT_SYMBOL(fscache_wait_bit_interruptible); -- cgit v1.2.2