Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache: (41 commits) NFS: Add mount options to enable local caching on NFS NFS: Display local caching state NFS: Store pages from an NFS inode into a local cache NFS: Read pages from FS-Cache into an NFS inode NFS: nfs_readpage_async() needs to be accessible as a fallback for local caching NFS: Add read context retention for FS-Cache to call back with NFS: FS-Cache page management NFS: Add some new I/O counters for FS-Cache doing things for NFS NFS: Invalidate FsCache page flags when cache removed NFS: Use local disk inode cache NFS: Define and create inode-level cache objects NFS: Define and create superblock-level objects NFS: Define and create server-level objects NFS: Register NFS for caching and retrieve the top-level index NFS: Permit local filesystem caching to be enabled for NFS NFS: Add FS-Cache option bit and debug bit NFS: Add comment banners to some NFS functions FS-Cache: Make kAFS use FS-Cache CacheFiles: A cache that backs onto a mounted filesystem CacheFiles: Export things for CacheFiles ...
This commit is contained in:
Linus Torvalds
@@ -0,0 +1,505 @@
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/* General filesystem caching backing cache interface
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*
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* Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* NOTE!!! See:
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*
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* Documentation/filesystems/caching/backend-api.txt
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*
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* for a description of the cache backend interface declared here.
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*/
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#ifndef _LINUX_FSCACHE_CACHE_H
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#define _LINUX_FSCACHE_CACHE_H
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#include <linux/fscache.h>
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#include <linux/sched.h>
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#include <linux/slow-work.h>
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#define NR_MAXCACHES BITS_PER_LONG
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struct fscache_cache;
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struct fscache_cache_ops;
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struct fscache_object;
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struct fscache_operation;
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/*
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* cache tag definition
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*/
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struct fscache_cache_tag {
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struct list_head link;
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struct fscache_cache *cache; /* cache referred to by this tag */
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unsigned long flags;
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#define FSCACHE_TAG_RESERVED 0 /* T if tag is reserved for a cache */
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atomic_t usage;
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char name[0]; /* tag name */
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};
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/*
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* cache definition
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*/
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struct fscache_cache {
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const struct fscache_cache_ops *ops;
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struct fscache_cache_tag *tag; /* tag representing this cache */
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struct kobject *kobj; /* system representation of this cache */
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struct list_head link; /* link in list of caches */
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size_t max_index_size; /* maximum size of index data */
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char identifier[36]; /* cache label */
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/* node management */
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struct work_struct op_gc; /* operation garbage collector */
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struct list_head object_list; /* list of data/index objects */
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struct list_head op_gc_list; /* list of ops to be deleted */
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spinlock_t object_list_lock;
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spinlock_t op_gc_list_lock;
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atomic_t object_count; /* no. of live objects in this cache */
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struct fscache_object *fsdef; /* object for the fsdef index */
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unsigned long flags;
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#define FSCACHE_IOERROR 0 /* cache stopped on I/O error */
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#define FSCACHE_CACHE_WITHDRAWN 1 /* cache has been withdrawn */
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};
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extern wait_queue_head_t fscache_cache_cleared_wq;
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/*
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* operation to be applied to a cache object
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* - retrieval initiation operations are done in the context of the process
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* that issued them, and not in an async thread pool
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*/
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typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
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typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
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struct fscache_operation {
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union {
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struct work_struct fast_work; /* record for fast ops */
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struct slow_work slow_work; /* record for (very) slow ops */
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};
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struct list_head pend_link; /* link in object->pending_ops */
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struct fscache_object *object; /* object to be operated upon */
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unsigned long flags;
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#define FSCACHE_OP_TYPE 0x000f /* operation type */
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#define FSCACHE_OP_FAST 0x0001 /* - fast op, processor may not sleep for disk */
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#define FSCACHE_OP_SLOW 0x0002 /* - (very) slow op, processor may sleep for disk */
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#define FSCACHE_OP_MYTHREAD 0x0003 /* - processing is done be issuing thread, not pool */
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#define FSCACHE_OP_WAITING 4 /* cleared when op is woken */
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#define FSCACHE_OP_EXCLUSIVE 5 /* exclusive op, other ops must wait */
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#define FSCACHE_OP_DEAD 6 /* op is now dead */
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atomic_t usage;
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unsigned debug_id; /* debugging ID */
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/* operation processor callback
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* - can be NULL if FSCACHE_OP_WAITING is going to be used to perform
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* the op in a non-pool thread */
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fscache_operation_processor_t processor;
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/* operation releaser */
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fscache_operation_release_t release;
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};
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extern atomic_t fscache_op_debug_id;
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extern const struct slow_work_ops fscache_op_slow_work_ops;
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extern void fscache_enqueue_operation(struct fscache_operation *);
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extern void fscache_put_operation(struct fscache_operation *);
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/**
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* fscache_operation_init - Do basic initialisation of an operation
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* @op: The operation to initialise
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* @release: The release function to assign
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*
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* Do basic initialisation of an operation. The caller must still set flags,
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* object, either fast_work or slow_work if necessary, and processor if needed.
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*/
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static inline void fscache_operation_init(struct fscache_operation *op,
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fscache_operation_release_t release)
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{
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atomic_set(&op->usage, 1);
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op->debug_id = atomic_inc_return(&fscache_op_debug_id);
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op->release = release;
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INIT_LIST_HEAD(&op->pend_link);
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}
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/**
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* fscache_operation_init_slow - Do additional initialisation of a slow op
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* @op: The operation to initialise
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* @processor: The processor function to assign
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*
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* Do additional initialisation of an operation as required for slow work.
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*/
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static inline
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void fscache_operation_init_slow(struct fscache_operation *op,
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fscache_operation_processor_t processor)
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{
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op->processor = processor;
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slow_work_init(&op->slow_work, &fscache_op_slow_work_ops);
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}
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/*
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* data read operation
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*/
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struct fscache_retrieval {
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struct fscache_operation op;
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struct address_space *mapping; /* netfs pages */
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fscache_rw_complete_t end_io_func; /* function to call on I/O completion */
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void *context; /* netfs read context (pinned) */
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struct list_head to_do; /* list of things to be done by the backend */
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unsigned long start_time; /* time at which retrieval started */
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};
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typedef int (*fscache_page_retrieval_func_t)(struct fscache_retrieval *op,
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struct page *page,
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gfp_t gfp);
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typedef int (*fscache_pages_retrieval_func_t)(struct fscache_retrieval *op,
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struct list_head *pages,
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unsigned *nr_pages,
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gfp_t gfp);
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/**
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* fscache_get_retrieval - Get an extra reference on a retrieval operation
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* @op: The retrieval operation to get a reference on
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*
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* Get an extra reference on a retrieval operation.
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*/
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static inline
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struct fscache_retrieval *fscache_get_retrieval(struct fscache_retrieval *op)
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{
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atomic_inc(&op->op.usage);
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return op;
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}
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/**
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* fscache_enqueue_retrieval - Enqueue a retrieval operation for processing
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* @op: The retrieval operation affected
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*
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* Enqueue a retrieval operation for processing by the FS-Cache thread pool.
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*/
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static inline void fscache_enqueue_retrieval(struct fscache_retrieval *op)
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{
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fscache_enqueue_operation(&op->op);
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}
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/**
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* fscache_put_retrieval - Drop a reference to a retrieval operation
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* @op: The retrieval operation affected
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*
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* Drop a reference to a retrieval operation.
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*/
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static inline void fscache_put_retrieval(struct fscache_retrieval *op)
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{
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fscache_put_operation(&op->op);
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}
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/*
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* cached page storage work item
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* - used to do three things:
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* - batch writes to the cache
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* - do cache writes asynchronously
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* - defer writes until cache object lookup completion
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*/
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struct fscache_storage {
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struct fscache_operation op;
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pgoff_t store_limit; /* don't write more than this */
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};
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/*
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* cache operations
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*/
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struct fscache_cache_ops {
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/* name of cache provider */
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const char *name;
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/* allocate an object record for a cookie */
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struct fscache_object *(*alloc_object)(struct fscache_cache *cache,
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struct fscache_cookie *cookie);
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/* look up the object for a cookie */
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void (*lookup_object)(struct fscache_object *object);
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/* finished looking up */
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void (*lookup_complete)(struct fscache_object *object);
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/* increment the usage count on this object (may fail if unmounting) */
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struct fscache_object *(*grab_object)(struct fscache_object *object);
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/* pin an object in the cache */
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int (*pin_object)(struct fscache_object *object);
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/* unpin an object in the cache */
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void (*unpin_object)(struct fscache_object *object);
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/* store the updated auxilliary data on an object */
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void (*update_object)(struct fscache_object *object);
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/* discard the resources pinned by an object and effect retirement if
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* necessary */
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void (*drop_object)(struct fscache_object *object);
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/* dispose of a reference to an object */
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void (*put_object)(struct fscache_object *object);
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/* sync a cache */
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void (*sync_cache)(struct fscache_cache *cache);
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/* notification that the attributes of a non-index object (such as
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* i_size) have changed */
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int (*attr_changed)(struct fscache_object *object);
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/* reserve space for an object's data and associated metadata */
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int (*reserve_space)(struct fscache_object *object, loff_t i_size);
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/* request a backing block for a page be read or allocated in the
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* cache */
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fscache_page_retrieval_func_t read_or_alloc_page;
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/* request backing blocks for a list of pages be read or allocated in
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* the cache */
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fscache_pages_retrieval_func_t read_or_alloc_pages;
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/* request a backing block for a page be allocated in the cache so that
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* it can be written directly */
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fscache_page_retrieval_func_t allocate_page;
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/* request backing blocks for pages be allocated in the cache so that
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* they can be written directly */
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fscache_pages_retrieval_func_t allocate_pages;
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/* write a page to its backing block in the cache */
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int (*write_page)(struct fscache_storage *op, struct page *page);
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/* detach backing block from a page (optional)
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* - must release the cookie lock before returning
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* - may sleep
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*/
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void (*uncache_page)(struct fscache_object *object,
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struct page *page);
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/* dissociate a cache from all the pages it was backing */
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void (*dissociate_pages)(struct fscache_cache *cache);
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};
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/*
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* data file or index object cookie
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* - a file will only appear in one cache
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* - a request to cache a file may or may not be honoured, subject to
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* constraints such as disk space
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* - indices are created on disk just-in-time
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*/
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struct fscache_cookie {
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atomic_t usage; /* number of users of this cookie */
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atomic_t n_children; /* number of children of this cookie */
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spinlock_t lock;
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struct hlist_head backing_objects; /* object(s) backing this file/index */
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const struct fscache_cookie_def *def; /* definition */
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struct fscache_cookie *parent; /* parent of this entry */
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void *netfs_data; /* back pointer to netfs */
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struct radix_tree_root stores; /* pages to be stored on this cookie */
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#define FSCACHE_COOKIE_PENDING_TAG 0 /* pages tag: pending write to cache */
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unsigned long flags;
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#define FSCACHE_COOKIE_LOOKING_UP 0 /* T if non-index cookie being looked up still */
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#define FSCACHE_COOKIE_CREATING 1 /* T if non-index object being created still */
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#define FSCACHE_COOKIE_NO_DATA_YET 2 /* T if new object with no cached data yet */
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#define FSCACHE_COOKIE_PENDING_FILL 3 /* T if pending initial fill on object */
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#define FSCACHE_COOKIE_FILLING 4 /* T if filling object incrementally */
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#define FSCACHE_COOKIE_UNAVAILABLE 5 /* T if cookie is unavailable (error, etc) */
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};
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extern struct fscache_cookie fscache_fsdef_index;
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/*
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* on-disk cache file or index handle
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*/
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struct fscache_object {
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enum fscache_object_state {
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FSCACHE_OBJECT_INIT, /* object in initial unbound state */
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FSCACHE_OBJECT_LOOKING_UP, /* looking up object */
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FSCACHE_OBJECT_CREATING, /* creating object */
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/* active states */
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FSCACHE_OBJECT_AVAILABLE, /* cleaning up object after creation */
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FSCACHE_OBJECT_ACTIVE, /* object is usable */
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FSCACHE_OBJECT_UPDATING, /* object is updating */
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/* terminal states */
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FSCACHE_OBJECT_DYING, /* object waiting for accessors to finish */
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FSCACHE_OBJECT_LC_DYING, /* object cleaning up after lookup/create */
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FSCACHE_OBJECT_ABORT_INIT, /* abort the init state */
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FSCACHE_OBJECT_RELEASING, /* releasing object */
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FSCACHE_OBJECT_RECYCLING, /* retiring object */
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FSCACHE_OBJECT_WITHDRAWING, /* withdrawing object */
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FSCACHE_OBJECT_DEAD, /* object is now dead */
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} state;
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int debug_id; /* debugging ID */
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int n_children; /* number of child objects */
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int n_ops; /* number of ops outstanding on object */
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int n_obj_ops; /* number of object ops outstanding on object */
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int n_in_progress; /* number of ops in progress */
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int n_exclusive; /* number of exclusive ops queued */
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spinlock_t lock; /* state and operations lock */
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unsigned long lookup_jif; /* time at which lookup started */
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unsigned long event_mask; /* events this object is interested in */
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unsigned long events; /* events to be processed by this object
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* (order is important - using fls) */
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#define FSCACHE_OBJECT_EV_REQUEUE 0 /* T if object should be requeued */
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#define FSCACHE_OBJECT_EV_UPDATE 1 /* T if object should be updated */
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#define FSCACHE_OBJECT_EV_CLEARED 2 /* T if accessors all gone */
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#define FSCACHE_OBJECT_EV_ERROR 3 /* T if fatal error occurred during processing */
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#define FSCACHE_OBJECT_EV_RELEASE 4 /* T if netfs requested object release */
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#define FSCACHE_OBJECT_EV_RETIRE 5 /* T if netfs requested object retirement */
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#define FSCACHE_OBJECT_EV_WITHDRAW 6 /* T if cache requested object withdrawal */
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unsigned long flags;
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#define FSCACHE_OBJECT_LOCK 0 /* T if object is busy being processed */
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#define FSCACHE_OBJECT_PENDING_WRITE 1 /* T if object has pending write */
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#define FSCACHE_OBJECT_WAITING 2 /* T if object is waiting on its parent */
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struct list_head cache_link; /* link in cache->object_list */
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struct hlist_node cookie_link; /* link in cookie->backing_objects */
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struct fscache_cache *cache; /* cache that supplied this object */
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struct fscache_cookie *cookie; /* netfs's file/index object */
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struct fscache_object *parent; /* parent object */
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struct slow_work work; /* attention scheduling record */
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struct list_head dependents; /* FIFO of dependent objects */
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struct list_head dep_link; /* link in parent's dependents list */
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struct list_head pending_ops; /* unstarted operations on this object */
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pgoff_t store_limit; /* current storage limit */
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};
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extern const char *fscache_object_states[];
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#define fscache_object_is_active(obj) \
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(!test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) && \
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(obj)->state >= FSCACHE_OBJECT_AVAILABLE && \
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(obj)->state < FSCACHE_OBJECT_DYING)
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extern const struct slow_work_ops fscache_object_slow_work_ops;
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/**
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* fscache_object_init - Initialise a cache object description
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* @object: Object description
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*
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* Initialise a cache object description to its basic values.
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*
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* See Documentation/filesystems/caching/backend-api.txt for a complete
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* description.
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||||
*/
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static inline
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void fscache_object_init(struct fscache_object *object,
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struct fscache_cookie *cookie,
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struct fscache_cache *cache)
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{
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atomic_inc(&cache->object_count);
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object->state = FSCACHE_OBJECT_INIT;
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spin_lock_init(&object->lock);
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INIT_LIST_HEAD(&object->cache_link);
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INIT_HLIST_NODE(&object->cookie_link);
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vslow_work_init(&object->work, &fscache_object_slow_work_ops);
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INIT_LIST_HEAD(&object->dependents);
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INIT_LIST_HEAD(&object->dep_link);
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INIT_LIST_HEAD(&object->pending_ops);
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object->n_children = 0;
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object->n_ops = object->n_in_progress = object->n_exclusive = 0;
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object->events = object->event_mask = 0;
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object->flags = 0;
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object->store_limit = 0;
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object->cache = cache;
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object->cookie = cookie;
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object->parent = NULL;
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}
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extern void fscache_object_lookup_negative(struct fscache_object *object);
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extern void fscache_obtained_object(struct fscache_object *object);
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/**
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* fscache_object_destroyed - Note destruction of an object in a cache
|
||||
* @cache: The cache from which the object came
|
||||
*
|
||||
* Note the destruction and deallocation of an object record in a cache.
|
||||
*/
|
||||
static inline void fscache_object_destroyed(struct fscache_cache *cache)
|
||||
{
|
||||
if (atomic_dec_and_test(&cache->object_count))
|
||||
wake_up_all(&fscache_cache_cleared_wq);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_object_lookup_error - Note an object encountered an error
|
||||
* @object: The object on which the error was encountered
|
||||
*
|
||||
* Note that an object encountered a fatal error (usually an I/O error) and
|
||||
* that it should be withdrawn as soon as possible.
|
||||
*/
|
||||
static inline void fscache_object_lookup_error(struct fscache_object *object)
|
||||
{
|
||||
set_bit(FSCACHE_OBJECT_EV_ERROR, &object->events);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_set_store_limit - Set the maximum size to be stored in an object
|
||||
* @object: The object to set the maximum on
|
||||
* @i_size: The limit to set in bytes
|
||||
*
|
||||
* Set the maximum size an object is permitted to reach, implying the highest
|
||||
* byte that may be written. Intended to be called by the attr_changed() op.
|
||||
*
|
||||
* See Documentation/filesystems/caching/backend-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_set_store_limit(struct fscache_object *object, loff_t i_size)
|
||||
{
|
||||
object->store_limit = i_size >> PAGE_SHIFT;
|
||||
if (i_size & ~PAGE_MASK)
|
||||
object->store_limit++;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_end_io - End a retrieval operation on a page
|
||||
* @op: The FS-Cache operation covering the retrieval
|
||||
* @page: The page that was to be fetched
|
||||
* @error: The error code (0 if successful)
|
||||
*
|
||||
* Note the end of an operation to retrieve a page, as covered by a particular
|
||||
* operation record.
|
||||
*/
|
||||
static inline void fscache_end_io(struct fscache_retrieval *op,
|
||||
struct page *page, int error)
|
||||
{
|
||||
op->end_io_func(page, op->context, error);
|
||||
}
|
||||
|
||||
/*
|
||||
* out-of-line cache backend functions
|
||||
*/
|
||||
extern void fscache_init_cache(struct fscache_cache *cache,
|
||||
const struct fscache_cache_ops *ops,
|
||||
const char *idfmt,
|
||||
...) __attribute__ ((format (printf, 3, 4)));
|
||||
|
||||
extern int fscache_add_cache(struct fscache_cache *cache,
|
||||
struct fscache_object *fsdef,
|
||||
const char *tagname);
|
||||
extern void fscache_withdraw_cache(struct fscache_cache *cache);
|
||||
|
||||
extern void fscache_io_error(struct fscache_cache *cache);
|
||||
|
||||
extern void fscache_mark_pages_cached(struct fscache_retrieval *op,
|
||||
struct pagevec *pagevec);
|
||||
|
||||
extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
|
||||
const void *data,
|
||||
uint16_t datalen);
|
||||
|
||||
#endif /* _LINUX_FSCACHE_CACHE_H */
|
||||
@@ -0,0 +1,618 @@
|
||||
/* General filesystem caching interface
|
||||
*
|
||||
* 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.
|
||||
*
|
||||
* NOTE!!! See:
|
||||
*
|
||||
* Documentation/filesystems/caching/netfs-api.txt
|
||||
*
|
||||
* for a description of the network filesystem interface declared here.
|
||||
*/
|
||||
|
||||
#ifndef _LINUX_FSCACHE_H
|
||||
#define _LINUX_FSCACHE_H
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/list.h>
|
||||
#include <linux/pagemap.h>
|
||||
#include <linux/pagevec.h>
|
||||
|
||||
#if defined(CONFIG_FSCACHE) || defined(CONFIG_FSCACHE_MODULE)
|
||||
#define fscache_available() (1)
|
||||
#define fscache_cookie_valid(cookie) (cookie)
|
||||
#else
|
||||
#define fscache_available() (0)
|
||||
#define fscache_cookie_valid(cookie) (0)
|
||||
#endif
|
||||
|
||||
|
||||
/*
|
||||
* overload PG_private_2 to give us PG_fscache - this is used to indicate that
|
||||
* a page is currently backed by a local disk cache
|
||||
*/
|
||||
#define PageFsCache(page) PagePrivate2((page))
|
||||
#define SetPageFsCache(page) SetPagePrivate2((page))
|
||||
#define ClearPageFsCache(page) ClearPagePrivate2((page))
|
||||
#define TestSetPageFsCache(page) TestSetPagePrivate2((page))
|
||||
#define TestClearPageFsCache(page) TestClearPagePrivate2((page))
|
||||
|
||||
/* pattern used to fill dead space in an index entry */
|
||||
#define FSCACHE_INDEX_DEADFILL_PATTERN 0x79
|
||||
|
||||
struct pagevec;
|
||||
struct fscache_cache_tag;
|
||||
struct fscache_cookie;
|
||||
struct fscache_netfs;
|
||||
|
||||
typedef void (*fscache_rw_complete_t)(struct page *page,
|
||||
void *context,
|
||||
int error);
|
||||
|
||||
/* result of index entry consultation */
|
||||
enum fscache_checkaux {
|
||||
FSCACHE_CHECKAUX_OKAY, /* entry okay as is */
|
||||
FSCACHE_CHECKAUX_NEEDS_UPDATE, /* entry requires update */
|
||||
FSCACHE_CHECKAUX_OBSOLETE, /* entry requires deletion */
|
||||
};
|
||||
|
||||
/*
|
||||
* fscache cookie definition
|
||||
*/
|
||||
struct fscache_cookie_def {
|
||||
/* name of cookie type */
|
||||
char name[16];
|
||||
|
||||
/* cookie type */
|
||||
uint8_t type;
|
||||
#define FSCACHE_COOKIE_TYPE_INDEX 0
|
||||
#define FSCACHE_COOKIE_TYPE_DATAFILE 1
|
||||
|
||||
/* select the cache into which to insert an entry in this index
|
||||
* - optional
|
||||
* - should return a cache identifier or NULL to cause the cache to be
|
||||
* inherited from the parent if possible or the first cache picked
|
||||
* for a non-index file if not
|
||||
*/
|
||||
struct fscache_cache_tag *(*select_cache)(
|
||||
const void *parent_netfs_data,
|
||||
const void *cookie_netfs_data);
|
||||
|
||||
/* get an index key
|
||||
* - should store the key data in the buffer
|
||||
* - should return the amount of amount stored
|
||||
* - not permitted to return an error
|
||||
* - the netfs data from the cookie being used as the source is
|
||||
* presented
|
||||
*/
|
||||
uint16_t (*get_key)(const void *cookie_netfs_data,
|
||||
void *buffer,
|
||||
uint16_t bufmax);
|
||||
|
||||
/* get certain file attributes from the netfs data
|
||||
* - this function can be absent for an index
|
||||
* - not permitted to return an error
|
||||
* - the netfs data from the cookie being used as the source is
|
||||
* presented
|
||||
*/
|
||||
void (*get_attr)(const void *cookie_netfs_data, uint64_t *size);
|
||||
|
||||
/* get the auxilliary data from netfs data
|
||||
* - this function can be absent if the index carries no state data
|
||||
* - should store the auxilliary data in the buffer
|
||||
* - should return the amount of amount stored
|
||||
* - not permitted to return an error
|
||||
* - the netfs data from the cookie being used as the source is
|
||||
* presented
|
||||
*/
|
||||
uint16_t (*get_aux)(const void *cookie_netfs_data,
|
||||
void *buffer,
|
||||
uint16_t bufmax);
|
||||
|
||||
/* consult the netfs about the state of an object
|
||||
* - this function can be absent if the index carries no state data
|
||||
* - the netfs data from the cookie being used as the target is
|
||||
* presented, as is the auxilliary data
|
||||
*/
|
||||
enum fscache_checkaux (*check_aux)(void *cookie_netfs_data,
|
||||
const void *data,
|
||||
uint16_t datalen);
|
||||
|
||||
/* get an extra reference on a read context
|
||||
* - this function can be absent if the completion function doesn't
|
||||
* require a context
|
||||
*/
|
||||
void (*get_context)(void *cookie_netfs_data, void *context);
|
||||
|
||||
/* release an extra reference on a read context
|
||||
* - this function can be absent if the completion function doesn't
|
||||
* require a context
|
||||
*/
|
||||
void (*put_context)(void *cookie_netfs_data, void *context);
|
||||
|
||||
/* indicate pages that now have cache metadata retained
|
||||
* - this function should mark the specified pages as now being cached
|
||||
* - the pages will have been marked with PG_fscache before this is
|
||||
* called, so this is optional
|
||||
*/
|
||||
void (*mark_pages_cached)(void *cookie_netfs_data,
|
||||
struct address_space *mapping,
|
||||
struct pagevec *cached_pvec);
|
||||
|
||||
/* indicate the cookie is no longer cached
|
||||
* - this function is called when the backing store currently caching
|
||||
* a cookie is removed
|
||||
* - the netfs should use this to clean up any markers indicating
|
||||
* cached pages
|
||||
* - this is mandatory for any object that may have data
|
||||
*/
|
||||
void (*now_uncached)(void *cookie_netfs_data);
|
||||
};
|
||||
|
||||
/*
|
||||
* fscache cached network filesystem type
|
||||
* - name, version and ops must be filled in before registration
|
||||
* - all other fields will be set during registration
|
||||
*/
|
||||
struct fscache_netfs {
|
||||
uint32_t version; /* indexing version */
|
||||
const char *name; /* filesystem name */
|
||||
struct fscache_cookie *primary_index;
|
||||
struct list_head link; /* internal link */
|
||||
};
|
||||
|
||||
/*
|
||||
* slow-path functions for when there is actually caching available, and the
|
||||
* netfs does actually have a valid token
|
||||
* - these are not to be called directly
|
||||
* - these are undefined symbols when FS-Cache is not configured and the
|
||||
* optimiser takes care of not using them
|
||||
*/
|
||||
extern int __fscache_register_netfs(struct fscache_netfs *);
|
||||
extern void __fscache_unregister_netfs(struct fscache_netfs *);
|
||||
extern struct fscache_cache_tag *__fscache_lookup_cache_tag(const char *);
|
||||
extern void __fscache_release_cache_tag(struct fscache_cache_tag *);
|
||||
|
||||
extern struct fscache_cookie *__fscache_acquire_cookie(
|
||||
struct fscache_cookie *,
|
||||
const struct fscache_cookie_def *,
|
||||
void *);
|
||||
extern void __fscache_relinquish_cookie(struct fscache_cookie *, int);
|
||||
extern void __fscache_update_cookie(struct fscache_cookie *);
|
||||
extern int __fscache_attr_changed(struct fscache_cookie *);
|
||||
extern int __fscache_read_or_alloc_page(struct fscache_cookie *,
|
||||
struct page *,
|
||||
fscache_rw_complete_t,
|
||||
void *,
|
||||
gfp_t);
|
||||
extern int __fscache_read_or_alloc_pages(struct fscache_cookie *,
|
||||
struct address_space *,
|
||||
struct list_head *,
|
||||
unsigned *,
|
||||
fscache_rw_complete_t,
|
||||
void *,
|
||||
gfp_t);
|
||||
extern int __fscache_alloc_page(struct fscache_cookie *, struct page *, gfp_t);
|
||||
extern int __fscache_write_page(struct fscache_cookie *, struct page *, gfp_t);
|
||||
extern void __fscache_uncache_page(struct fscache_cookie *, struct page *);
|
||||
extern bool __fscache_check_page_write(struct fscache_cookie *, struct page *);
|
||||
extern void __fscache_wait_on_page_write(struct fscache_cookie *, struct page *);
|
||||
|
||||
/**
|
||||
* fscache_register_netfs - Register a filesystem as desiring caching services
|
||||
* @netfs: The description of the filesystem
|
||||
*
|
||||
* Register a filesystem as desiring caching services if they're available.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_register_netfs(struct fscache_netfs *netfs)
|
||||
{
|
||||
if (fscache_available())
|
||||
return __fscache_register_netfs(netfs);
|
||||
else
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_unregister_netfs - Indicate that a filesystem no longer desires
|
||||
* caching services
|
||||
* @netfs: The description of the filesystem
|
||||
*
|
||||
* Indicate that a filesystem no longer desires caching services for the
|
||||
* moment.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_unregister_netfs(struct fscache_netfs *netfs)
|
||||
{
|
||||
if (fscache_available())
|
||||
__fscache_unregister_netfs(netfs);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_lookup_cache_tag - Look up a cache tag
|
||||
* @name: The name of the tag to search for
|
||||
*
|
||||
* Acquire a specific cache referral tag that can be used to select a specific
|
||||
* cache in which to cache an index.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
struct fscache_cache_tag *fscache_lookup_cache_tag(const char *name)
|
||||
{
|
||||
if (fscache_available())
|
||||
return __fscache_lookup_cache_tag(name);
|
||||
else
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_release_cache_tag - Release a cache tag
|
||||
* @tag: The tag to release
|
||||
*
|
||||
* Release a reference to a cache referral tag previously looked up.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_release_cache_tag(struct fscache_cache_tag *tag)
|
||||
{
|
||||
if (fscache_available())
|
||||
__fscache_release_cache_tag(tag);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_acquire_cookie - Acquire a cookie to represent a cache object
|
||||
* @parent: The cookie that's to be the parent of this one
|
||||
* @def: A description of the cache object, including callback operations
|
||||
* @netfs_data: An arbitrary piece of data to be kept in the cookie to
|
||||
* represent the cache object to the netfs
|
||||
*
|
||||
* This function is used to inform FS-Cache about part of an index hierarchy
|
||||
* that can be used to locate files. This is done by requesting a cookie for
|
||||
* each index in the path to the file.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
struct fscache_cookie *fscache_acquire_cookie(
|
||||
struct fscache_cookie *parent,
|
||||
const struct fscache_cookie_def *def,
|
||||
void *netfs_data)
|
||||
{
|
||||
if (fscache_cookie_valid(parent))
|
||||
return __fscache_acquire_cookie(parent, def, netfs_data);
|
||||
else
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_relinquish_cookie - Return the cookie to the cache, maybe discarding
|
||||
* it
|
||||
* @cookie: The cookie being returned
|
||||
* @retire: True if the cache object the cookie represents is to be discarded
|
||||
*
|
||||
* This function returns a cookie to the cache, forcibly discarding the
|
||||
* associated cache object if retire is set to true.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
__fscache_relinquish_cookie(cookie, retire);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_update_cookie - Request that a cache object be updated
|
||||
* @cookie: The cookie representing the cache object
|
||||
*
|
||||
* Request an update of the index data for the cache object associated with the
|
||||
* cookie.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_update_cookie(struct fscache_cookie *cookie)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
__fscache_update_cookie(cookie);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_pin_cookie - Pin a data-storage cache object in its cache
|
||||
* @cookie: The cookie representing the cache object
|
||||
*
|
||||
* Permit data-storage cache objects to be pinned in the cache.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_pin_cookie(struct fscache_cookie *cookie)
|
||||
{
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_pin_cookie - Unpin a data-storage cache object in its cache
|
||||
* @cookie: The cookie representing the cache object
|
||||
*
|
||||
* Permit data-storage cache objects to be unpinned from the cache.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_unpin_cookie(struct fscache_cookie *cookie)
|
||||
{
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_attr_changed - Notify cache that an object's attributes changed
|
||||
* @cookie: The cookie representing the cache object
|
||||
*
|
||||
* Send a notification to the cache indicating that an object's attributes have
|
||||
* changed. This includes the data size. These attributes will be obtained
|
||||
* through the get_attr() cookie definition op.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_attr_changed(struct fscache_cookie *cookie)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
return __fscache_attr_changed(cookie);
|
||||
else
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_reserve_space - Reserve data space for a cached object
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @i_size: The amount of space to be reserved
|
||||
*
|
||||
* Reserve an amount of space in the cache for the cache object attached to a
|
||||
* cookie so that a write to that object within the space can always be
|
||||
* honoured.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_reserve_space(struct fscache_cookie *cookie, loff_t size)
|
||||
{
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_read_or_alloc_page - Read a page from the cache or allocate a block
|
||||
* in which to store it
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @page: The netfs page to fill if possible
|
||||
* @end_io_func: The callback to invoke when and if the page is filled
|
||||
* @context: An arbitrary piece of data to pass on to end_io_func()
|
||||
* @gfp: The conditions under which memory allocation should be made
|
||||
*
|
||||
* Read a page from the cache, or if that's not possible make a potential
|
||||
* one-block reservation in the cache into which the page may be stored once
|
||||
* fetched from the server.
|
||||
*
|
||||
* If the page is not backed by the cache object, or if it there's some reason
|
||||
* it can't be, -ENOBUFS will be returned and nothing more will be done for
|
||||
* that page.
|
||||
*
|
||||
* Else, if that page is backed by the cache, a read will be initiated directly
|
||||
* to the netfs's page and 0 will be returned by this function. The
|
||||
* end_io_func() callback will be invoked when the operation terminates on a
|
||||
* completion or failure. Note that the callback may be invoked before the
|
||||
* return.
|
||||
*
|
||||
* Else, if the page is unbacked, -ENODATA is returned and a block may have
|
||||
* been allocated in the cache.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_read_or_alloc_page(struct fscache_cookie *cookie,
|
||||
struct page *page,
|
||||
fscache_rw_complete_t end_io_func,
|
||||
void *context,
|
||||
gfp_t gfp)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
return __fscache_read_or_alloc_page(cookie, page, end_io_func,
|
||||
context, gfp);
|
||||
else
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_read_or_alloc_pages - Read pages from the cache and/or allocate
|
||||
* blocks in which to store them
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @mapping: The netfs inode mapping to which the pages will be attached
|
||||
* @pages: A list of potential netfs pages to be filled
|
||||
* @end_io_func: The callback to invoke when and if each page is filled
|
||||
* @context: An arbitrary piece of data to pass on to end_io_func()
|
||||
* @gfp: The conditions under which memory allocation should be made
|
||||
*
|
||||
* Read a set of pages from the cache, or if that's not possible, attempt to
|
||||
* make a potential one-block reservation for each page in the cache into which
|
||||
* that page may be stored once fetched from the server.
|
||||
*
|
||||
* If some pages are not backed by the cache object, or if it there's some
|
||||
* reason they can't be, -ENOBUFS will be returned and nothing more will be
|
||||
* done for that pages.
|
||||
*
|
||||
* Else, if some of the pages are backed by the cache, a read will be initiated
|
||||
* directly to the netfs's page and 0 will be returned by this function. The
|
||||
* end_io_func() callback will be invoked when the operation terminates on a
|
||||
* completion or failure. Note that the callback may be invoked before the
|
||||
* return.
|
||||
*
|
||||
* Else, if a page is unbacked, -ENODATA is returned and a block may have
|
||||
* been allocated in the cache.
|
||||
*
|
||||
* Because the function may want to return all of -ENOBUFS, -ENODATA and 0 in
|
||||
* regard to different pages, the return values are prioritised in that order.
|
||||
* Any pages submitted for reading are removed from the pages list.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
|
||||
struct address_space *mapping,
|
||||
struct list_head *pages,
|
||||
unsigned *nr_pages,
|
||||
fscache_rw_complete_t end_io_func,
|
||||
void *context,
|
||||
gfp_t gfp)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
return __fscache_read_or_alloc_pages(cookie, mapping, pages,
|
||||
nr_pages, end_io_func,
|
||||
context, gfp);
|
||||
else
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_alloc_page - Allocate a block in which to store a page
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @page: The netfs page to allocate a page for
|
||||
* @gfp: The conditions under which memory allocation should be made
|
||||
*
|
||||
* Request Allocation a block in the cache in which to store a netfs page
|
||||
* without retrieving any contents from the cache.
|
||||
*
|
||||
* If the page is not backed by a file then -ENOBUFS will be returned and
|
||||
* nothing more will be done, and no reservation will be made.
|
||||
*
|
||||
* Else, a block will be allocated if one wasn't already, and 0 will be
|
||||
* returned
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_alloc_page(struct fscache_cookie *cookie,
|
||||
struct page *page,
|
||||
gfp_t gfp)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
return __fscache_alloc_page(cookie, page, gfp);
|
||||
else
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_write_page - Request storage of a page in the cache
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @page: The netfs page to store
|
||||
* @gfp: The conditions under which memory allocation should be made
|
||||
*
|
||||
* Request the contents of the netfs page be written into the cache. This
|
||||
* request may be ignored if no cache block is currently allocated, in which
|
||||
* case it will return -ENOBUFS.
|
||||
*
|
||||
* If a cache block was already allocated, a write will be initiated and 0 will
|
||||
* be returned. The PG_fscache_write page bit is set immediately and will then
|
||||
* be cleared at the completion of the write to indicate the success or failure
|
||||
* of the operation. Note that the completion may happen before the return.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
int fscache_write_page(struct fscache_cookie *cookie,
|
||||
struct page *page,
|
||||
gfp_t gfp)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
return __fscache_write_page(cookie, page, gfp);
|
||||
else
|
||||
return -ENOBUFS;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_uncache_page - Indicate that caching is no longer required on a page
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @page: The netfs page that was being cached.
|
||||
*
|
||||
* Tell the cache that we no longer want a page to be cached and that it should
|
||||
* remove any knowledge of the netfs page it may have.
|
||||
*
|
||||
* Note that this cannot cancel any outstanding I/O operations between this
|
||||
* page and the cache.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_uncache_page(struct fscache_cookie *cookie,
|
||||
struct page *page)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
__fscache_uncache_page(cookie, page);
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_check_page_write - Ask if a page is being writing to the cache
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @page: The netfs page that is being cached.
|
||||
*
|
||||
* Ask the cache if a page is being written to the cache.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
bool fscache_check_page_write(struct fscache_cookie *cookie,
|
||||
struct page *page)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
return __fscache_check_page_write(cookie, page);
|
||||
return false;
|
||||
}
|
||||
|
||||
/**
|
||||
* fscache_wait_on_page_write - Wait for a page to complete writing to the cache
|
||||
* @cookie: The cookie representing the cache object
|
||||
* @page: The netfs page that is being cached.
|
||||
*
|
||||
* Ask the cache to wake us up when a page is no longer being written to the
|
||||
* cache.
|
||||
*
|
||||
* See Documentation/filesystems/caching/netfs-api.txt for a complete
|
||||
* description.
|
||||
*/
|
||||
static inline
|
||||
void fscache_wait_on_page_write(struct fscache_cookie *cookie,
|
||||
struct page *page)
|
||||
{
|
||||
if (fscache_cookie_valid(cookie))
|
||||
__fscache_wait_on_page_write(cookie, page);
|
||||
}
|
||||
|
||||
#endif /* _LINUX_FSCACHE_H */
|
||||
@@ -185,6 +185,9 @@ struct nfs_inode {
|
||||
fmode_t delegation_state;
|
||||
struct rw_semaphore rwsem;
|
||||
#endif /* CONFIG_NFS_V4*/
|
||||
#ifdef CONFIG_NFS_FSCACHE
|
||||
struct fscache_cookie *fscache;
|
||||
#endif
|
||||
struct inode vfs_inode;
|
||||
};
|
||||
|
||||
@@ -207,6 +210,8 @@ struct nfs_inode {
|
||||
#define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */
|
||||
#define NFS_INO_MOUNTPOINT (3) /* inode is remote mountpoint */
|
||||
#define NFS_INO_FLUSHING (4) /* inode is flushing out data */
|
||||
#define NFS_INO_FSCACHE (5) /* inode can be cached by FS-Cache */
|
||||
#define NFS_INO_FSCACHE_LOCK (6) /* FS-Cache cookie management lock */
|
||||
|
||||
static inline struct nfs_inode *NFS_I(const struct inode *inode)
|
||||
{
|
||||
@@ -260,6 +265,11 @@ static inline int NFS_STALE(const struct inode *inode)
|
||||
return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
|
||||
}
|
||||
|
||||
static inline int NFS_FSCACHE(const struct inode *inode)
|
||||
{
|
||||
return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
|
||||
}
|
||||
|
||||
static inline __u64 NFS_FILEID(const struct inode *inode)
|
||||
{
|
||||
return NFS_I(inode)->fileid;
|
||||
@@ -506,6 +516,8 @@ extern int nfs_readpages(struct file *, struct address_space *,
|
||||
struct list_head *, unsigned);
|
||||
extern int nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
|
||||
extern void nfs_readdata_release(void *data);
|
||||
extern int nfs_readpage_async(struct nfs_open_context *, struct inode *,
|
||||
struct page *);
|
||||
|
||||
/*
|
||||
* Allocate nfs_read_data structures
|
||||
@@ -583,6 +595,7 @@ extern void * nfs_root_data(void);
|
||||
#define NFSDBG_CALLBACK 0x0100
|
||||
#define NFSDBG_CLIENT 0x0200
|
||||
#define NFSDBG_MOUNT 0x0400
|
||||
#define NFSDBG_FSCACHE 0x0800
|
||||
#define NFSDBG_ALL 0xFFFF
|
||||
|
||||
#ifdef __KERNEL__
|
||||
|
||||
@@ -64,6 +64,10 @@ struct nfs_client {
|
||||
char cl_ipaddr[48];
|
||||
unsigned char cl_id_uniquifier;
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_NFS_FSCACHE
|
||||
struct fscache_cookie *fscache; /* client index cache cookie */
|
||||
#endif
|
||||
};
|
||||
|
||||
/*
|
||||
@@ -96,12 +100,19 @@ struct nfs_server {
|
||||
unsigned int acdirmin;
|
||||
unsigned int acdirmax;
|
||||
unsigned int namelen;
|
||||
unsigned int options; /* extra options enabled by mount */
|
||||
#define NFS_OPTION_FSCACHE 0x00000001 /* - local caching enabled */
|
||||
|
||||
struct nfs_fsid fsid;
|
||||
__u64 maxfilesize; /* maximum file size */
|
||||
unsigned long mount_time; /* when this fs was mounted */
|
||||
dev_t s_dev; /* superblock dev numbers */
|
||||
|
||||
#ifdef CONFIG_NFS_FSCACHE
|
||||
struct nfs_fscache_key *fscache_key; /* unique key for superblock */
|
||||
struct fscache_cookie *fscache; /* superblock cookie */
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_NFS_V4
|
||||
u32 attr_bitmask[2];/* V4 bitmask representing the set
|
||||
of attributes supported on this
|
||||
|
||||
@@ -116,4 +116,16 @@ enum nfs_stat_eventcounters {
|
||||
__NFSIOS_COUNTSMAX,
|
||||
};
|
||||
|
||||
/*
|
||||
* NFS local caching servicing counters
|
||||
*/
|
||||
enum nfs_stat_fscachecounters {
|
||||
NFSIOS_FSCACHE_PAGES_READ_OK,
|
||||
NFSIOS_FSCACHE_PAGES_READ_FAIL,
|
||||
NFSIOS_FSCACHE_PAGES_WRITTEN_OK,
|
||||
NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL,
|
||||
NFSIOS_FSCACHE_PAGES_UNCACHED,
|
||||
__NFSIOS_FSCACHEMAX,
|
||||
};
|
||||
|
||||
#endif /* _LINUX_NFS_IOSTAT */
|
||||
|
||||
@@ -82,6 +82,7 @@ enum pageflags {
|
||||
PG_arch_1,
|
||||
PG_reserved,
|
||||
PG_private, /* If pagecache, has fs-private data */
|
||||
PG_private_2, /* If pagecache, has fs aux data */
|
||||
PG_writeback, /* Page is under writeback */
|
||||
#ifdef CONFIG_PAGEFLAGS_EXTENDED
|
||||
PG_head, /* A head page */
|
||||
@@ -108,6 +109,12 @@ enum pageflags {
|
||||
/* Filesystems */
|
||||
PG_checked = PG_owner_priv_1,
|
||||
|
||||
/* Two page bits are conscripted by FS-Cache to maintain local caching
|
||||
* state. These bits are set on pages belonging to the netfs's inodes
|
||||
* when those inodes are being locally cached.
|
||||
*/
|
||||
PG_fscache = PG_private_2, /* page backed by cache */
|
||||
|
||||
/* XEN */
|
||||
PG_pinned = PG_owner_priv_1,
|
||||
PG_savepinned = PG_dirty,
|
||||
@@ -182,7 +189,7 @@ static inline int TestClearPage##uname(struct page *page) { return 0; }
|
||||
|
||||
struct page; /* forward declaration */
|
||||
|
||||
TESTPAGEFLAG(Locked, locked)
|
||||
TESTPAGEFLAG(Locked, locked) TESTSETFLAG(Locked, locked)
|
||||
PAGEFLAG(Error, error)
|
||||
PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(Referenced, referenced)
|
||||
PAGEFLAG(Dirty, dirty) TESTSCFLAG(Dirty, dirty) __CLEARPAGEFLAG(Dirty, dirty)
|
||||
@@ -194,8 +201,6 @@ PAGEFLAG(Checked, checked) /* Used by some filesystems */
|
||||
PAGEFLAG(Pinned, pinned) TESTSCFLAG(Pinned, pinned) /* Xen */
|
||||
PAGEFLAG(SavePinned, savepinned); /* Xen */
|
||||
PAGEFLAG(Reserved, reserved) __CLEARPAGEFLAG(Reserved, reserved)
|
||||
PAGEFLAG(Private, private) __CLEARPAGEFLAG(Private, private)
|
||||
__SETPAGEFLAG(Private, private)
|
||||
PAGEFLAG(SwapBacked, swapbacked) __CLEARPAGEFLAG(SwapBacked, swapbacked)
|
||||
|
||||
__PAGEFLAG(SlobPage, slob_page)
|
||||
@@ -204,6 +209,16 @@ __PAGEFLAG(SlobFree, slob_free)
|
||||
__PAGEFLAG(SlubFrozen, slub_frozen)
|
||||
__PAGEFLAG(SlubDebug, slub_debug)
|
||||
|
||||
/*
|
||||
* Private page markings that may be used by the filesystem that owns the page
|
||||
* for its own purposes.
|
||||
* - PG_private and PG_private_2 cause releasepage() and co to be invoked
|
||||
*/
|
||||
PAGEFLAG(Private, private) __SETPAGEFLAG(Private, private)
|
||||
__CLEARPAGEFLAG(Private, private)
|
||||
PAGEFLAG(Private2, private_2) TESTSCFLAG(Private2, private_2)
|
||||
PAGEFLAG(OwnerPriv1, owner_priv_1) TESTCLEARFLAG(OwnerPriv1, owner_priv_1)
|
||||
|
||||
/*
|
||||
* Only test-and-set exist for PG_writeback. The unconditional operators are
|
||||
* risky: they bypass page accounting.
|
||||
@@ -384,9 +399,10 @@ static inline void __ClearPageTail(struct page *page)
|
||||
* these flags set. It they are, there is a problem.
|
||||
*/
|
||||
#define PAGE_FLAGS_CHECK_AT_FREE \
|
||||
(1 << PG_lru | 1 << PG_private | 1 << PG_locked | \
|
||||
1 << PG_buddy | 1 << PG_writeback | 1 << PG_reserved | \
|
||||
1 << PG_slab | 1 << PG_swapcache | 1 << PG_active | \
|
||||
(1 << PG_lru | 1 << PG_locked | \
|
||||
1 << PG_private | 1 << PG_private_2 | \
|
||||
1 << PG_buddy | 1 << PG_writeback | 1 << PG_reserved | \
|
||||
1 << PG_slab | 1 << PG_swapcache | 1 << PG_active | \
|
||||
__PG_UNEVICTABLE | __PG_MLOCKED)
|
||||
|
||||
/*
|
||||
@@ -397,4 +413,16 @@ static inline void __ClearPageTail(struct page *page)
|
||||
#define PAGE_FLAGS_CHECK_AT_PREP ((1 << NR_PAGEFLAGS) - 1)
|
||||
|
||||
#endif /* !__GENERATING_BOUNDS_H */
|
||||
|
||||
/**
|
||||
* page_has_private - Determine if page has private stuff
|
||||
* @page: The page to be checked
|
||||
*
|
||||
* Determine if a page has private stuff, indicating that release routines
|
||||
* should be invoked upon it.
|
||||
*/
|
||||
#define page_has_private(page) \
|
||||
((page)->flags & ((1 << PG_private) | \
|
||||
(1 << PG_private_2)))
|
||||
|
||||
#endif /* PAGE_FLAGS_H */
|
||||
|
||||
@@ -383,6 +383,11 @@ static inline void wait_on_page_writeback(struct page *page)
|
||||
|
||||
extern void end_page_writeback(struct page *page);
|
||||
|
||||
/*
|
||||
* Add an arbitrary waiter to a page's wait queue
|
||||
*/
|
||||
extern void add_page_wait_queue(struct page *page, wait_queue_t *waiter);
|
||||
|
||||
/*
|
||||
* Fault a userspace page into pagetables. Return non-zero on a fault.
|
||||
*
|
||||
|
||||
@@ -0,0 +1,95 @@
|
||||
/* Worker thread pool for slow items, such as filesystem lookups or mkdirs
|
||||
*
|
||||
* Copyright (C) 2008 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 Licence
|
||||
* as published by the Free Software Foundation; either version
|
||||
* 2 of the Licence, or (at your option) any later version.
|
||||
*
|
||||
* See Documentation/slow-work.txt
|
||||
*/
|
||||
|
||||
#ifndef _LINUX_SLOW_WORK_H
|
||||
#define _LINUX_SLOW_WORK_H
|
||||
|
||||
#ifdef CONFIG_SLOW_WORK
|
||||
|
||||
#include <linux/sysctl.h>
|
||||
|
||||
struct slow_work;
|
||||
|
||||
/*
|
||||
* The operations used to support slow work items
|
||||
*/
|
||||
struct slow_work_ops {
|
||||
/* get a ref on a work item
|
||||
* - return 0 if successful, -ve if not
|
||||
*/
|
||||
int (*get_ref)(struct slow_work *work);
|
||||
|
||||
/* discard a ref to a work item */
|
||||
void (*put_ref)(struct slow_work *work);
|
||||
|
||||
/* execute a work item */
|
||||
void (*execute)(struct slow_work *work);
|
||||
};
|
||||
|
||||
/*
|
||||
* A slow work item
|
||||
* - A reference is held on the parent object by the thread pool when it is
|
||||
* queued
|
||||
*/
|
||||
struct slow_work {
|
||||
unsigned long flags;
|
||||
#define SLOW_WORK_PENDING 0 /* item pending (further) execution */
|
||||
#define SLOW_WORK_EXECUTING 1 /* item currently executing */
|
||||
#define SLOW_WORK_ENQ_DEFERRED 2 /* item enqueue deferred */
|
||||
#define SLOW_WORK_VERY_SLOW 3 /* item is very slow */
|
||||
const struct slow_work_ops *ops; /* operations table for this item */
|
||||
struct list_head link; /* link in queue */
|
||||
};
|
||||
|
||||
/**
|
||||
* slow_work_init - Initialise a slow work item
|
||||
* @work: The work item to initialise
|
||||
* @ops: The operations to use to handle the slow work item
|
||||
*
|
||||
* Initialise a slow work item.
|
||||
*/
|
||||
static inline void slow_work_init(struct slow_work *work,
|
||||
const struct slow_work_ops *ops)
|
||||
{
|
||||
work->flags = 0;
|
||||
work->ops = ops;
|
||||
INIT_LIST_HEAD(&work->link);
|
||||
}
|
||||
|
||||
/**
|
||||
* slow_work_init - Initialise a very slow work item
|
||||
* @work: The work item to initialise
|
||||
* @ops: The operations to use to handle the slow work item
|
||||
*
|
||||
* Initialise a very slow work item. This item will be restricted such that
|
||||
* only a certain number of the pool threads will be able to execute items of
|
||||
* this type.
|
||||
*/
|
||||
static inline void vslow_work_init(struct slow_work *work,
|
||||
const struct slow_work_ops *ops)
|
||||
{
|
||||
work->flags = 1 << SLOW_WORK_VERY_SLOW;
|
||||
work->ops = ops;
|
||||
INIT_LIST_HEAD(&work->link);
|
||||
}
|
||||
|
||||
extern int slow_work_enqueue(struct slow_work *work);
|
||||
extern int slow_work_register_user(void);
|
||||
extern void slow_work_unregister_user(void);
|
||||
|
||||
#ifdef CONFIG_SYSCTL
|
||||
extern ctl_table slow_work_sysctls[];
|
||||
#endif
|
||||
|
||||
#endif /* CONFIG_SLOW_WORK */
|
||||
#endif /* _LINUX_SLOW_WORK_H */
|
||||
Reference in New Issue
Block a user