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Diffstat (limited to 'fs/cachefiles/internal.h')
| -rw-r--r-- | fs/cachefiles/internal.h | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h new file mode 100644 index 000000000..2ad58c465 --- /dev/null +++ b/fs/cachefiles/internal.h @@ -0,0 +1,477 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* General netfs cache on cache files internal defs + * + * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#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 */ +}; + +/* + * 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; + u8 d_name_len; /* Length of filename */ + 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 + int ondemand_id; +#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 *secctx; /* LSM security context */ + 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; +}; + +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; + int error; + struct cachefiles_msg msg; +}; + +#define CACHEFILES_REQ_NEW XA_MARK_1 + +#include <trace/events/cachefiles.h> + +static inline +struct file *cachefiles_cres_file(struct netfs_cache_resources *cres) +{ + return cres->cache_priv2; +} + +static inline +struct 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_get_unbind_pincount(struct cachefiles_cache *cache); +extern void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache); + +/* + * error_inject.c + */ +#ifdef CONFIG_CACHEFILES_ERROR_INJECTION +extern 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, + 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_ONDEMAND +extern 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_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); + +#else +static 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; +} +#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); \ +} 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 |