--- /dev/null
+/* internal.h: general netfs cache on cache files internal defs
+ *
+ * Copyright (C) 2006 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.
+ *
+ *
+ * CacheFiles layout:
+ *
+ * /..../CacheDir/
+ * index
+ * 0/
+ * 1/
+ * 2/
+ * index
+ * 0/
+ * 1/
+ * 2/
+ * index
+ * 0
+ * 1
+ * 2
+ */
+
+#include <linux/fscache-cache.h>
+#include <linux/timer.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+struct cachefiles_cache;
+struct cachefiles_object;
+
+extern unsigned long cachefiles_debug;
+#define CACHEFILES_DEBUG_KENTER 1
+#define CACHEFILES_DEBUG_KLEAVE 2
+#define CACHEFILES_DEBUG_KDEBUG 4
+
+extern struct fscache_cache_ops cachefiles_cache_ops;
+extern struct proc_dir_entry *cachefiles_proc;
+extern struct file_operations cachefiles_proc_fops;
+
+/*****************************************************************************/
+/*
+ * node records
+ */
+struct cachefiles_object {
+ struct fscache_object fscache; /* fscache handle */
+ struct dentry *dentry; /* the file/dir representing this object */
+ struct dentry *backer; /* backing file */
+ loff_t i_size; /* object size */
+ atomic_t usage; /* basic object usage count */
+ atomic_t fscache_usage; /* FSDEF object usage count */
+ uint8_t type; /* object type */
+ uint8_t new; /* T if object new */
+ spinlock_t work_lock;
+ struct rw_semaphore sem;
+ struct work_struct read_work; /* read page copier */
+ struct list_head read_list; /* pages to copy */
+ struct list_head read_pend_list; /* pages to pending read from backer */
+ struct work_struct write_work; /* page writer */
+ struct list_head write_list; /* pages to store */
+ struct rb_node active_node; /* link in active tree (dentry is key) */
+};
+
+extern kmem_cache_t *cachefiles_object_jar;
+
+/*****************************************************************************/
+/*
+ * Cache files cache definition
+ */
+struct cachefiles_cache {
+ struct fscache_cache cache; /* FS-Cache record */
+ struct vfsmount *mnt; /* mountpoint holding the cache */
+ struct dentry *graveyard; /* directory into which dead objects go */
+ struct file *cachefilesd; /* manager daemon handle */
+ struct rb_root active_nodes; /* active nodes (can't be culled) */
+ rwlock_t active_lock; /* lock for active_nodes */
+ atomic_t gravecounter; /* graveyard uniquifier */
+ unsigned brun_percent; /* when to stop culling (%) */
+ unsigned bcull_percent; /* when to start culling (%) */
+ unsigned bstop_percent; /* when to stop allocating (%) */
+ unsigned bsize; /* cache's block size */
+ unsigned bshift; /* min(log2 (PAGE_SIZE / bsize), 0) */
+ sector_t brun; /* when to stop culling */
+ sector_t bcull; /* when to start culling */
+ sector_t bstop; /* when to stop allocating */
+ unsigned long flags;
+#define CACHEFILES_READY 0 /* T if cache prepared */
+#define CACHEFILES_DEAD 1 /* T if cache dead */
+#define CACHEFILES_CULLING 2 /* T if cull engaged */
+ char *rootdirname; /* name of cache root directory */
+ char *tag; /* cache binding tag */
+};
+
+/*****************************************************************************/
+/*
+ * backing file read tracking
+ */
+struct cachefiles_one_read {
+ wait_queue_t monitor; /* link into monitored waitqueue */
+ struct page *back_page; /* backing file page we're waiting for */
+ struct page *netfs_page; /* netfs page we're going to fill */
+ struct cachefiles_object *object;
+ struct list_head obj_link; /* link in object's lists */
+ fscache_rw_complete_t end_io_func;
+ void *context;
+};
+
+/*****************************************************************************/
+/*
+ * backing file write tracking
+ */
+struct cachefiles_one_write {
+ struct page *netfs_page; /* netfs page to copy */
+ struct cachefiles_object *object;
+ struct list_head obj_link; /* link in object's lists */
+ fscache_rw_complete_t end_io_func;
+ void *context;
+};
+
+/*****************************************************************************/
+/*
+ * auxiliary data xattr buffer
+ */
+struct cachefiles_xattr {
+ uint16_t len;
+ uint8_t type;
+ uint8_t data[];
+};
+
+
+/* cf-bind.c */
+extern int cachefiles_proc_bind(struct cachefiles_cache *cache, char *args);
+extern void cachefiles_proc_unbind(struct cachefiles_cache *cache);
+
+/* cf-interface.c */
+extern void cachefiles_read_copier_work(void *_object);
+extern void cachefiles_write_work(void *_object);
+extern int cachefiles_has_space(struct cachefiles_cache *cache, unsigned nr);
+
+/* cf-key.c */
+extern char *cachefiles_cook_key(const u8 *raw, int keylen, uint8_t type);
+
+/* cf-namei.c */
+extern int cachefiles_delete_object(struct cachefiles_cache *cache,
+ struct cachefiles_object *object);
+extern int cachefiles_walk_to_object(struct cachefiles_object *parent,
+ struct cachefiles_object *object,
+ char *key,
+ struct cachefiles_xattr *auxdata);
+extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
+ struct dentry *dir,
+ const char *name);
+
+extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir,
+ char *filename);
+
+/* cf-sysctl.c */
+extern int __init cachefiles_sysctl_init(void);
+extern void __exit cachefiles_sysctl_cleanup(void);
+
+/* cf-xattr.c */
+extern int cachefiles_check_object_type(struct cachefiles_object *object);
+extern int cachefiles_set_object_xattr(struct cachefiles_object *object,
+ struct cachefiles_xattr *auxdata);
+extern int cachefiles_check_object_xattr(struct cachefiles_object *object,
+ struct cachefiles_xattr *auxdata);
+extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
+ struct dentry *dentry);
+
+
+/*****************************************************************************/
+/*
+ * error handling
+ */
+#define kerror(FMT,...) printk(KERN_ERR "CacheFiles: "FMT"\n" ,##__VA_ARGS__);
+
+#define cachefiles_io_error(___cache, FMT, ...) \
+do { \
+ kerror("I/O Error: " FMT ,##__VA_ARGS__); \
+ fscache_io_error(&(___cache)->cache); \
+ set_bit(CACHEFILES_DEAD, &(___cache)->flags); \
+} while(0)
+
+#define cachefiles_io_error_obj(object, FMT, ...) \
+do { \
+ struct cachefiles_cache *___cache; \
+ \
+ ___cache = container_of((object)->fscache.cache, \
+ struct cachefiles_cache, cache); \
+ cachefiles_io_error(___cache, FMT ,##__VA_ARGS__); \
+} while(0)
+
+
+/*****************************************************************************/
+/*
+ * debug tracing
+ */
+#define dbgprintk(FMT,...) \
+ printk("[%-6.6s] "FMT"\n",current->comm ,##__VA_ARGS__)
+
+/* make sure we maintain the format strings, even when debugging is disabled */
+static inline void _dbprintk(const char *fmt, ...)
+ __attribute__((format(printf,1,2)));
+static inline void _dbprintk(const char *fmt, ...)
+{
+}
+
+#define kenter(FMT,...) dbgprintk("==> %s("FMT")",__FUNCTION__ ,##__VA_ARGS__)
+#define kleave(FMT,...) dbgprintk("<== %s()"FMT"",__FUNCTION__ ,##__VA_ARGS__)
+#define kdebug(FMT,...) dbgprintk(FMT ,##__VA_ARGS__)
+
+
+#if defined(__KDEBUG)
+#define _enter(FMT,...) kenter(FMT,##__VA_ARGS__)
+#define _leave(FMT,...) kleave(FMT,##__VA_ARGS__)
+#define _debug(FMT,...) kdebug(FMT,##__VA_ARGS__)
+
+#elif defined(CONFIG_CACHEFILES_DEBUG)
+#define _enter(FMT,...) \
+do { \
+ if (cachefiles_debug & CACHEFILES_DEBUG_KENTER) \
+ kenter(FMT,##__VA_ARGS__); \
+} while (0)
+
+#define _leave(FMT,...) \
+do { \
+ if (cachefiles_debug & CACHEFILES_DEBUG_KLEAVE) \
+ kleave(FMT,##__VA_ARGS__); \
+} while (0)
+
+#define _debug(FMT,...) \
+do { \
+ if (cachefiles_debug & CACHEFILES_DEBUG_KDEBUG) \
+ kdebug(FMT,##__VA_ARGS__); \
+} while (0)
+
+#else
+#define _enter(FMT,...) _dbprintk("==> %s("FMT")",__FUNCTION__ ,##__VA_ARGS__)
+#define _leave(FMT,...) _dbprintk("<== %s()"FMT"",__FUNCTION__ ,##__VA_ARGS__)
+#define _debug(FMT,...) _dbprintk(FMT ,##__VA_ARGS__)
+#endif
+
+#if 1 // defined(__KDEBUGALL)
+
+#define ASSERT(X) \
+do { \
+ if (unlikely(!(X))) { \
+ printk(KERN_ERR "\n"); \
+ printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
+ BUG(); \
+ } \
+} while(0)
+
+#define ASSERTCMP(X, OP, Y) \
+do { \
+ if (unlikely(!((X) OP (Y)))) { \
+ printk(KERN_ERR "\n"); \
+ printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
+ printk(KERN_ERR "%lx " #OP " %lx is false\n", \
+ (unsigned long)(X), (unsigned long)(Y)); \
+ BUG(); \
+ } \
+} while(0)
+
+#define ASSERTIF(C, X) \
+do { \
+ if (unlikely((C) && !(X))) { \
+ printk(KERN_ERR "\n"); \
+ printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
+ BUG(); \
+ } \
+} while(0)
+
+#define ASSERTIFCMP(C, X, OP, Y) \
+do { \
+ if (unlikely((C) && !((X) OP (Y)))) { \
+ printk(KERN_ERR "\n"); \
+ printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
+ printk(KERN_ERR "%lx " #OP " %lx is false\n", \
+ (unsigned long)(X), (unsigned long)(Y)); \
+ BUG(); \
+ } \
+} while(0)
+
+#else
+
+#define ASSERT(X) \
+do { \
+} while(0)
+
+#define ASSERTCMP(X, OP, Y) \
+do { \
+} while(0)
+
+#define ASSERTIF(C, X) \
+do { \
+} while(0)
+
+#define ASSERTIFCMP(C, X, OP, Y) \
+do { \
+} while(0)
+
+#endif
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