diff options
Diffstat (limited to 'include/linux/fscache.h')
| -rw-r--r-- | include/linux/fscache.h | 142 |
1 files changed, 83 insertions, 59 deletions
diff --git a/include/linux/fscache.h b/include/linux/fscache.h index fe0c349684fa..84b90a79d75a 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -22,6 +22,7 @@ #include <linux/list.h> #include <linux/pagemap.h> #include <linux/pagevec.h> +#include <linux/list_bl.h> #if defined(CONFIG_FSCACHE) || defined(CONFIG_FSCACHE_MODULE) #define fscache_available() (1) @@ -83,45 +84,15 @@ struct fscache_cookie_def { 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 data 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 auxiliary data from netfs data - * - this function can be absent if the index carries no state data - * - should store the auxiliary 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 auxiliary data + * presented, as is the auxiliary data and the object size */ enum fscache_checkaux (*check_aux)(void *cookie_netfs_data, const void *data, - uint16_t datalen); + uint16_t datalen, + loff_t object_size); /* get an extra reference on a read context * - this function can be absent if the completion function doesn't @@ -154,7 +125,6 @@ struct fscache_netfs { uint32_t version; /* indexing version */ const char *name; /* filesystem name */ struct fscache_cookie *primary_index; - struct list_head link; /* internal link */ }; /* @@ -173,6 +143,7 @@ struct fscache_cookie { struct hlist_head backing_objects; /* object(s) backing this file/index */ const struct fscache_cookie_def *def; /* definition */ struct fscache_cookie *parent; /* parent of this entry */ + struct hlist_bl_node hash_link; /* Link in hash table */ void *netfs_data; /* back pointer to netfs */ struct radix_tree_root stores; /* pages to be stored on this cookie */ #define FSCACHE_COOKIE_PENDING_TAG 0 /* pages tag: pending write to cache */ @@ -186,6 +157,22 @@ struct fscache_cookie { #define FSCACHE_COOKIE_RELINQUISHED 4 /* T if cookie has been relinquished */ #define FSCACHE_COOKIE_ENABLED 5 /* T if cookie is enabled */ #define FSCACHE_COOKIE_ENABLEMENT_LOCK 6 /* T if cookie is being en/disabled */ +#define FSCACHE_COOKIE_AUX_UPDATED 8 /* T if the auxiliary data was updated */ +#define FSCACHE_COOKIE_ACQUIRED 9 /* T if cookie is in use */ +#define FSCACHE_COOKIE_RELINQUISHING 10 /* T if cookie is being relinquished */ + + u8 type; /* Type of object */ + u8 key_len; /* Length of index key */ + u8 aux_len; /* Length of auxiliary data */ + u32 key_hash; /* Hash of parent, type, key, len */ + union { + void *key; /* Index key */ + u8 inline_key[16]; /* - If the key is short enough */ + }; + union { + void *aux; /* Auxiliary data */ + u8 inline_aux[8]; /* - If the aux data is short enough */ + }; }; static inline bool fscache_cookie_enabled(struct fscache_cookie *cookie) @@ -208,10 +195,12 @@ 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 *, bool); -extern void __fscache_relinquish_cookie(struct fscache_cookie *, bool); -extern int __fscache_check_consistency(struct fscache_cookie *); -extern void __fscache_update_cookie(struct fscache_cookie *); + const void *, size_t, + const void *, size_t, + void *, loff_t, bool); +extern void __fscache_relinquish_cookie(struct fscache_cookie *, const void *, bool); +extern int __fscache_check_consistency(struct fscache_cookie *, const void *); +extern void __fscache_update_cookie(struct fscache_cookie *, const void *); extern int __fscache_attr_changed(struct fscache_cookie *); extern void __fscache_invalidate(struct fscache_cookie *); extern void __fscache_wait_on_invalidate(struct fscache_cookie *); @@ -228,7 +217,7 @@ extern int __fscache_read_or_alloc_pages(struct fscache_cookie *, 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 int __fscache_write_page(struct fscache_cookie *, struct page *, loff_t, 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 *); @@ -238,8 +227,8 @@ extern void __fscache_uncache_all_inode_pages(struct fscache_cookie *, struct inode *); extern void __fscache_readpages_cancel(struct fscache_cookie *cookie, struct list_head *pages); -extern void __fscache_disable_cookie(struct fscache_cookie *, bool); -extern void __fscache_enable_cookie(struct fscache_cookie *, +extern void __fscache_disable_cookie(struct fscache_cookie *, const void *, bool); +extern void __fscache_enable_cookie(struct fscache_cookie *, const void *, loff_t, bool (*)(void *), void *); /** @@ -317,8 +306,13 @@ void fscache_release_cache_tag(struct fscache_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 + * @index_key: The index key for this cookie + * @index_key_len: Size of the index key + * @aux_data: The auxiliary data for the cookie (may be NULL) + * @aux_data_len: Size of the auxiliary data buffer * @netfs_data: An arbitrary piece of data to be kept in the cookie to * represent the cache object to the netfs + * @object_size: The initial size of object * @enable: Whether or not to enable a data cookie immediately * * This function is used to inform FS-Cache about part of an index hierarchy @@ -332,12 +326,19 @@ static inline struct fscache_cookie *fscache_acquire_cookie( struct fscache_cookie *parent, const struct fscache_cookie_def *def, + const void *index_key, + size_t index_key_len, + const void *aux_data, + size_t aux_data_len, void *netfs_data, + loff_t object_size, bool enable) { if (fscache_cookie_valid(parent) && fscache_cookie_enabled(parent)) - return __fscache_acquire_cookie(parent, def, netfs_data, - enable); + return __fscache_acquire_cookie(parent, def, + index_key, index_key_len, + aux_data, aux_data_len, + netfs_data, object_size, enable); else return NULL; } @@ -346,36 +347,44 @@ struct fscache_cookie *fscache_acquire_cookie( * fscache_relinquish_cookie - Return the cookie to the cache, maybe discarding * it * @cookie: The cookie being returned + * @aux_data: The updated auxiliary data for the cookie (may be NULL) * @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. + * associated cache object if retire is set to true. The opportunity is + * provided to update the auxiliary data in the cache before the object is + * disconnected. * * See Documentation/filesystems/caching/netfs-api.txt for a complete * description. */ static inline -void fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire) +void fscache_relinquish_cookie(struct fscache_cookie *cookie, + const void *aux_data, + bool retire) { if (fscache_cookie_valid(cookie)) - __fscache_relinquish_cookie(cookie, retire); + __fscache_relinquish_cookie(cookie, aux_data, retire); } /** - * fscache_check_consistency - Request that if the cache is updated + * fscache_check_consistency - Request validation of a cache's auxiliary data * @cookie: The cookie representing the cache object + * @aux_data: The updated auxiliary data for the cookie (may be NULL) * - * Request an consistency check from fscache, which passes the request - * to the backing cache. + * Request an consistency check from fscache, which passes the request to the + * backing cache. The auxiliary data on the cookie will be updated first if + * @aux_data is set. * * Returns 0 if consistent and -ESTALE if inconsistent. May also * return -ENOMEM and -ERESTARTSYS. */ static inline -int fscache_check_consistency(struct fscache_cookie *cookie) +int fscache_check_consistency(struct fscache_cookie *cookie, + const void *aux_data) { if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - return __fscache_check_consistency(cookie); + return __fscache_check_consistency(cookie, aux_data); else return 0; } @@ -383,18 +392,20 @@ int fscache_check_consistency(struct fscache_cookie *cookie) /** * fscache_update_cookie - Request that a cache object be updated * @cookie: The cookie representing the cache object + * @aux_data: The updated auxiliary data for the cookie (may be NULL) * * Request an update of the index data for the cache object associated with the - * cookie. + * cookie. The auxiliary data on the cookie will be updated first if @aux_data + * is set. * * See Documentation/filesystems/caching/netfs-api.txt for a complete * description. */ static inline -void fscache_update_cookie(struct fscache_cookie *cookie) +void fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data) { if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - __fscache_update_cookie(cookie); + __fscache_update_cookie(cookie, aux_data); } /** @@ -648,6 +659,7 @@ void fscache_readpages_cancel(struct fscache_cookie *cookie, * fscache_write_page - Request storage of a page in the cache * @cookie: The cookie representing the cache object * @page: The netfs page to store + * @object_size: Updated size of object * @gfp: The conditions under which memory allocation should be made * * Request the contents of the netfs page be written into the cache. This @@ -665,10 +677,11 @@ void fscache_readpages_cancel(struct fscache_cookie *cookie, static inline int fscache_write_page(struct fscache_cookie *cookie, struct page *page, + loff_t object_size, gfp_t gfp) { if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - return __fscache_write_page(cookie, page, gfp); + return __fscache_write_page(cookie, page, object_size, gfp); else return -ENOBUFS; } @@ -780,6 +793,7 @@ void fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, /** * fscache_disable_cookie - Disable a cookie * @cookie: The cookie representing the cache object + * @aux_data: The updated auxiliary data for the cookie (may be NULL) * @invalidate: Invalidate the backing object * * Disable a cookie from accepting further alloc, read, write, invalidate, @@ -790,34 +804,44 @@ void fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, * * If @invalidate is set, then the backing object will be invalidated and * detached, otherwise it will just be detached. + * + * If @aux_data is set, then auxiliary data will be updated from that. */ static inline -void fscache_disable_cookie(struct fscache_cookie *cookie, bool invalidate) +void fscache_disable_cookie(struct fscache_cookie *cookie, + const void *aux_data, + bool invalidate) { if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - __fscache_disable_cookie(cookie, invalidate); + __fscache_disable_cookie(cookie, aux_data, invalidate); } /** * fscache_enable_cookie - Reenable a cookie * @cookie: The cookie representing the cache object + * @aux_data: The updated auxiliary data for the cookie (may be NULL) + * @object_size: Current size of object * @can_enable: A function to permit enablement once lock is held * @data: Data for can_enable() * * Reenable a previously disabled cookie, allowing it to accept further alloc, * read, write, invalidate, update or acquire operations. An attempt will be - * made to immediately reattach the cookie to a backing object. + * made to immediately reattach the cookie to a backing object. If @aux_data + * is set, the auxiliary data attached to the cookie will be updated. * * The can_enable() function is called (if not NULL) once the enablement lock * is held to rule on whether enablement is still permitted to go ahead. */ static inline void fscache_enable_cookie(struct fscache_cookie *cookie, + const void *aux_data, + loff_t object_size, bool (*can_enable)(void *data), void *data) { if (fscache_cookie_valid(cookie) && !fscache_cookie_enabled(cookie)) - __fscache_enable_cookie(cookie, can_enable, data); + __fscache_enable_cookie(cookie, aux_data, object_size, + can_enable, data); } #endif /* _LINUX_FSCACHE_H */ |