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#ifdef pr_fmt#undef pr_fmt#endif
#define pr_fmt(fmt) "CacheFiles: " fmt
#include <linux/fscache-cache.h>#include <linux/cred.h>#include <linux/security.h>#include <linux/xarray.h>#include <linux/cachefiles.h>
#define CACHEFILES_DIO_BLOCK_SIZE 4096
struct cachefiles_cache;struct cachefiles_object;
enum cachefiles_content { /* These values are saved on disk */ CACHEFILES_CONTENT_NO_DATA = 0, /* No content stored */ CACHEFILES_CONTENT_SINGLE = 1, /* Content is monolithic, all is present */ CACHEFILES_CONTENT_ALL = 2, /* Content is all present, no map */ CACHEFILES_CONTENT_BACKFS_MAP = 3, /* Content is piecemeal, mapped through backing fs */ CACHEFILES_CONTENT_DIRTY = 4, /* Content is dirty (only seen on disk) */ nr__cachefiles_content};
/* * Cached volume representation. */struct cachefiles_volume { struct cachefiles_cache *cache; struct list_head cache_link; /* Link in cache->volumes */ struct fscache_volume *vcookie; /* The netfs's representation */ struct dentry *dentry; /* The volume dentry */ struct dentry *fanout[256]; /* Fanout subdirs */};
enum cachefiles_object_state { CACHEFILES_ONDEMAND_OBJSTATE_CLOSE, /* Anonymous fd closed by daemon or initial state */ CACHEFILES_ONDEMAND_OBJSTATE_OPEN, /* Anonymous fd associated with object is available */ CACHEFILES_ONDEMAND_OBJSTATE_REOPENING, /* Object that was closed and is being reopened. */ CACHEFILES_ONDEMAND_OBJSTATE_DROPPING, /* Object is being dropped. */};
struct cachefiles_ondemand_info { struct work_struct ondemand_work; int ondemand_id; enum cachefiles_object_state state; struct cachefiles_object *object; spinlock_t lock;};
/* * Backing file state. */struct cachefiles_object { struct fscache_cookie *cookie; /* Netfs data storage object cookie */ struct cachefiles_volume *volume; /* Cache volume that holds this object */ struct list_head cache_link; /* Link in cache->*_list */ struct file *file; /* The file representing this object */ char *d_name; /* Backing file name */ int debug_id; spinlock_t lock; refcount_t ref; enum cachefiles_content content_info:8; /* Info about content presence */ unsigned long flags;#define CACHEFILES_OBJECT_USING_TMPFILE 0 /* Have an unlinked tmpfile */#ifdef CONFIG_CACHEFILES_ONDEMAND struct cachefiles_ondemand_info *ondemand;#endif};
#define CACHEFILES_ONDEMAND_ID_CLOSED -1
/* * Cache files cache definition */struct cachefiles_cache { struct fscache_cache *cache; /* Cache cookie */ struct vfsmount *mnt; /* mountpoint holding the cache */ struct dentry *store; /* Directory into which live objects go */ struct dentry *graveyard; /* directory into which dead objects go */ struct file *cachefilesd; /* manager daemon handle */ struct list_head volumes; /* List of volume objects */ struct list_head object_list; /* List of active objects */ spinlock_t object_list_lock; /* Lock for volumes and object_list */ const struct cred *cache_cred; /* security override for accessing cache */ struct mutex daemon_mutex; /* command serialisation mutex */ wait_queue_head_t daemon_pollwq; /* poll waitqueue for daemon */ atomic_t gravecounter; /* graveyard uniquifier */ atomic_t f_released; /* number of objects released lately */ atomic_long_t b_released; /* number of blocks released lately */ atomic_long_t b_writing; /* Number of blocks being written */ unsigned frun_percent; /* when to stop culling (% files) */ unsigned fcull_percent; /* when to start culling (% files) */ unsigned fstop_percent; /* when to stop allocating (% files) */ unsigned brun_percent; /* when to stop culling (% blocks) */ unsigned bcull_percent; /* when to start culling (% blocks) */ unsigned bstop_percent; /* when to stop allocating (% blocks) */ unsigned bsize; /* cache's block size */ unsigned bshift; /* ilog2(bsize) */ uint64_t frun; /* when to stop culling */ uint64_t fcull; /* when to start culling */ uint64_t fstop; /* when to stop allocating */ 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 */#define CACHEFILES_STATE_CHANGED 3 /* T if state changed (poll trigger) */#define CACHEFILES_ONDEMAND_MODE 4 /* T if in on-demand read mode */ char *rootdirname; /* name of cache root directory */ char *tag; /* cache binding tag */ refcount_t unbind_pincount;/* refcount to do daemon unbind */ struct xarray reqs; /* xarray of pending on-demand requests */ unsigned long req_id_next; struct xarray ondemand_ids; /* xarray for ondemand_id allocation */ u32 ondemand_id_next; u32 msg_id_next; u32 secid; /* LSM security id */ bool have_secid; /* whether "secid" was set */};
static inline bool cachefiles_in_ondemand_mode(struct cachefiles_cache *cache){ return IS_ENABLED(CONFIG_CACHEFILES_ONDEMAND) && test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags);}
struct cachefiles_req { struct cachefiles_object *object; struct completion done; refcount_t ref; int error; struct cachefiles_msg msg;};
#define CACHEFILES_REQ_NEW XA_MARK_1
#include <trace/events/cachefiles.h>
static inlinestruct file *cachefiles_cres_file(struct netfs_cache_resources *cres){ return cres->cache_priv2;}
static inlinestruct cachefiles_object *cachefiles_cres_object(struct netfs_cache_resources *cres){ return fscache_cres_cookie(cres)->cache_priv;}
/* * note change of state for daemon */static inline void cachefiles_state_changed(struct cachefiles_cache *cache){ set_bit(CACHEFILES_STATE_CHANGED, &cache->flags); wake_up_all(&cache->daemon_pollwq);}
/* * cache.c */extern int cachefiles_add_cache(struct cachefiles_cache *cache);extern void cachefiles_withdraw_cache(struct cachefiles_cache *cache);
enum cachefiles_has_space_for { cachefiles_has_space_check, cachefiles_has_space_for_write, cachefiles_has_space_for_create,};extern int cachefiles_has_space(struct cachefiles_cache *cache, unsigned fnr, unsigned bnr, enum cachefiles_has_space_for reason);
/* * daemon.c */extern const struct file_operations cachefiles_daemon_fops;extern void cachefiles_flush_reqs(struct cachefiles_cache *cache);extern void cachefiles_get_unbind_pincount(struct cachefiles_cache *cache);extern void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache);
/* * error_inject.c */#ifdef CONFIG_CACHEFILES_ERROR_INJECTIONextern unsigned int cachefiles_error_injection_state;extern int cachefiles_register_error_injection(void);extern void cachefiles_unregister_error_injection(void);
#else#define cachefiles_error_injection_state 0
static inline int cachefiles_register_error_injection(void){ return 0;}
static inline void cachefiles_unregister_error_injection(void){}#endif
static inline int cachefiles_inject_read_error(void){ return cachefiles_error_injection_state & 2 ? -EIO : 0;}
static inline int cachefiles_inject_write_error(void){ return cachefiles_error_injection_state & 2 ? -EIO : cachefiles_error_injection_state & 1 ? -ENOSPC : 0;}
static inline int cachefiles_inject_remove_error(void){ return cachefiles_error_injection_state & 2 ? -EIO : 0;}
/* * interface.c */extern const struct fscache_cache_ops cachefiles_cache_ops;extern void cachefiles_see_object(struct cachefiles_object *object, enum cachefiles_obj_ref_trace why);extern struct cachefiles_object *cachefiles_grab_object(struct cachefiles_object *object, enum cachefiles_obj_ref_trace why);extern void cachefiles_put_object(struct cachefiles_object *object, enum cachefiles_obj_ref_trace why);
/* * io.c */extern bool cachefiles_begin_operation(struct netfs_cache_resources *cres, enum fscache_want_state want_state);extern int __cachefiles_prepare_write(struct cachefiles_object *object, struct file *file, loff_t *_start, size_t *_len, size_t upper_len, bool no_space_allocated_yet);extern int __cachefiles_write(struct cachefiles_object *object, struct file *file, loff_t start_pos, struct iov_iter *iter, netfs_io_terminated_t term_func, void *term_func_priv);
/* * key.c */extern bool cachefiles_cook_key(struct cachefiles_object *object);
/* * main.c */extern struct kmem_cache *cachefiles_object_jar;
/* * namei.c */extern void cachefiles_unmark_inode_in_use(struct cachefiles_object *object, struct file *file);extern int cachefiles_bury_object(struct cachefiles_cache *cache, struct cachefiles_object *object, struct dentry *dir, struct dentry *rep, enum fscache_why_object_killed why);extern int cachefiles_delete_object(struct cachefiles_object *object, enum fscache_why_object_killed why);extern bool cachefiles_look_up_object(struct cachefiles_object *object);extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, struct dentry *dir, const char *name, bool *_is_new);extern void cachefiles_put_directory(struct dentry *dir);
extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir, char *filename);
extern int cachefiles_check_in_use(struct cachefiles_cache *cache, struct dentry *dir, char *filename);extern struct file *cachefiles_create_tmpfile(struct cachefiles_object *object);extern bool cachefiles_commit_tmpfile(struct cachefiles_cache *cache, struct cachefiles_object *object);
/* * ondemand.c */#ifdef CONFIG_CACHEFILES_ONDEMANDextern ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, char __user *_buffer, size_t buflen);
extern int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args);
extern int cachefiles_ondemand_restore(struct cachefiles_cache *cache, char *args);
extern int cachefiles_ondemand_init_object(struct cachefiles_object *object);extern void cachefiles_ondemand_clean_object(struct cachefiles_object *object);
extern int cachefiles_ondemand_read(struct cachefiles_object *object, loff_t pos, size_t len);
extern int cachefiles_ondemand_init_obj_info(struct cachefiles_object *obj, struct cachefiles_volume *volume);extern void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *obj);
#define CACHEFILES_OBJECT_STATE_FUNCS(_state, _STATE) \static inline bool \cachefiles_ondemand_object_is_##_state(const struct cachefiles_object *object) \{ \ return object->ondemand->state == CACHEFILES_ONDEMAND_OBJSTATE_##_STATE; \} \ \static inline void \cachefiles_ondemand_set_object_##_state(struct cachefiles_object *object) \{ \ object->ondemand->state = CACHEFILES_ONDEMAND_OBJSTATE_##_STATE; \}
CACHEFILES_OBJECT_STATE_FUNCS(open, OPEN);CACHEFILES_OBJECT_STATE_FUNCS(close, CLOSE);CACHEFILES_OBJECT_STATE_FUNCS(reopening, REOPENING);CACHEFILES_OBJECT_STATE_FUNCS(dropping, DROPPING);
static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req){ return cachefiles_ondemand_object_is_reopening(req->object) && req->msg.opcode == CACHEFILES_OP_READ;}
#elsestatic inline ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, char __user *_buffer, size_t buflen){ return -EOPNOTSUPP;}
static inline int cachefiles_ondemand_init_object(struct cachefiles_object *object){ return 0;}
static inline void cachefiles_ondemand_clean_object(struct cachefiles_object *object){}
static inline int cachefiles_ondemand_read(struct cachefiles_object *object, loff_t pos, size_t len){ return -EOPNOTSUPP;}
static inline int cachefiles_ondemand_init_obj_info(struct cachefiles_object *obj, struct cachefiles_volume *volume){ return 0;}static inline void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *obj){}
static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req){ return false;}#endif
/* * security.c */extern int cachefiles_get_security_ID(struct cachefiles_cache *cache);extern int cachefiles_determine_cache_security(struct cachefiles_cache *cache, struct dentry *root, const struct cred **_saved_cred);
static inline void cachefiles_begin_secure(struct cachefiles_cache *cache, const struct cred **_saved_cred){ *_saved_cred = override_creds(cache->cache_cred);}
static inline void cachefiles_end_secure(struct cachefiles_cache *cache, const struct cred *saved_cred){ revert_creds(saved_cred);}
/* * volume.c */void cachefiles_acquire_volume(struct fscache_volume *volume);void cachefiles_free_volume(struct fscache_volume *volume);void cachefiles_withdraw_volume(struct cachefiles_volume *volume);
/* * xattr.c */extern int cachefiles_set_object_xattr(struct cachefiles_object *object);extern int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file);extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, struct cachefiles_object *object, struct dentry *dentry);extern void cachefiles_prepare_to_write(struct fscache_cookie *cookie);extern bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume);extern int cachefiles_check_volume_xattr(struct cachefiles_volume *volume);
/* * Error handling */#define cachefiles_io_error(___cache, FMT, ...) \do { \ pr_err("I/O Error: " FMT"\n", ##__VA_ARGS__); \ fscache_io_error((___cache)->cache); \ set_bit(CACHEFILES_DEAD, &(___cache)->flags); \ if (cachefiles_in_ondemand_mode(___cache)) \ cachefiles_flush_reqs(___cache); \} while (0)
#define cachefiles_io_error_obj(object, FMT, ...) \do { \ struct cachefiles_cache *___cache; \ \ ___cache = (object)->volume->cache; \ cachefiles_io_error(___cache, FMT " [o=%08x]", ##__VA_ARGS__, \ (object)->debug_id); \} while (0)
/* * Debug tracing */extern unsigned cachefiles_debug;#define CACHEFILES_DEBUG_KENTER 1#define CACHEFILES_DEBUG_KLEAVE 2#define CACHEFILES_DEBUG_KDEBUG 4
#define dbgprintk(FMT, ...) \ printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__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, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)#endif
#if 1 /* defined(__KDEBUGALL) */
#define ASSERT(X) \do { \ if (unlikely(!(X))) { \ pr_err("\n"); \ pr_err("Assertion failed\n"); \ BUG(); \ } \} while (0)
#define ASSERTCMP(X, OP, Y) \do { \ if (unlikely(!((X) OP (Y)))) { \ pr_err("\n"); \ pr_err("Assertion failed\n"); \ pr_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))) { \ pr_err("\n"); \ pr_err("Assertion failed\n"); \ BUG(); \ } \} while (0)
#define ASSERTIFCMP(C, X, OP, Y) \do { \ if (unlikely((C) && !((X) OP (Y)))) { \ pr_err("\n"); \ pr_err("Assertion failed\n"); \ pr_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