fscache: Pass object size in rather than calling back for it
Pass the object size in to fscache_acquire_cookie() and
fscache_write_page() rather than the netfs providing a callback by which it
can be received. This makes it easier to update the size of the object
when a new page is written that extends the object.
The current object size is also passed by fscache to the check_aux
function, obviating the need to store it in the aux data.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
diff --git a/include/linux/fscache.h b/include/linux/fscache.h
index a2d3a21..eb38f39 100644
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -83,22 +83,15 @@ struct fscache_cookie_def {
const void *parent_netfs_data,
const void *cookie_netfs_data);
- /* 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);
-
/* 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
@@ -200,7 +193,7 @@ extern struct fscache_cookie *__fscache_acquire_cookie(
const struct fscache_cookie_def *,
const void *, size_t,
const void *, size_t,
- void *, bool);
+ 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 *);
@@ -220,7 +213,7 @@ 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 *);
@@ -231,7 +224,7 @@ extern void __fscache_uncache_all_inode_pages(struct fscache_cookie *,
extern void __fscache_readpages_cancel(struct fscache_cookie *cookie,
struct list_head *pages);
extern void __fscache_disable_cookie(struct fscache_cookie *, const void *, bool);
-extern void __fscache_enable_cookie(struct fscache_cookie *, const void *,
+extern void __fscache_enable_cookie(struct fscache_cookie *, const void *, loff_t,
bool (*)(void *), void *);
/**
@@ -315,6 +308,7 @@ void fscache_release_cache_tag(struct fscache_cache_tag *tag)
* @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
@@ -333,13 +327,14 @@ struct fscache_cookie *fscache_acquire_cookie(
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,
index_key, index_key_len,
aux_data, aux_data_len,
- netfs_data, enable);
+ netfs_data, object_size, enable);
else
return NULL;
}
@@ -660,6 +655,7 @@ 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
@@ -677,10 +673,11 @@ 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;
}
@@ -819,6 +816,7 @@ void fscache_disable_cookie(struct fscache_cookie *cookie,
* 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()
*
@@ -833,11 +831,13 @@ void fscache_disable_cookie(struct fscache_cookie *cookie,
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, aux_data, can_enable, data);
+ __fscache_enable_cookie(cookie, aux_data, object_size,
+ can_enable, data);
}
#endif /* _LINUX_FSCACHE_H */