1 files changed, 58 insertions, 13 deletions

diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index ce31408b1e47..5dfa0aa216b6 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -75,6 +75,16 @@ extern wait_queue_head_t fscache_cache_cleared_wq;
 typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
 typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
 
+enum fscache_operation_state {
+        FSCACHE_OP_ST_BLANK,            /* Op is not yet submitted */
+        FSCACHE_OP_ST_INITIALISED,      /* Op is initialised */
+        FSCACHE_OP_ST_PENDING,          /* Op is blocked from running */
+        FSCACHE_OP_ST_IN_PROGRESS,      /* Op is in progress */
+        FSCACHE_OP_ST_COMPLETE,         /* Op is complete */
+        FSCACHE_OP_ST_CANCELLED,        /* Op has been cancelled */
+        FSCACHE_OP_ST_DEAD              /* Op is now dead */
+};
+
 struct fscache_operation {
         struct work_struct      work;           /* record for async ops */
         struct list_head        pend_link;      /* link in object->pending_ops */
@@ -86,10 +96,10 @@ struct fscache_operation {
 #define FSCACHE_OP_MYTHREAD     0x0002  /* - processing is done be issuing thread, not pool */
 #define FSCACHE_OP_WAITING      4       /* cleared when op is woken */
 #define FSCACHE_OP_EXCLUSIVE    5       /* exclusive op, other ops must wait */
-#define FSCACHE_OP_DEAD         6       /* op is now dead */
-#define FSCACHE_OP_DEC_READ_CNT 7       /* decrement object->n_reads on destruction */
-#define FSCACHE_OP_KEEP_FLAGS   0xc0    /* flags to keep when repurposing an op */
+#define FSCACHE_OP_DEC_READ_CNT 6       /* decrement object->n_reads on destruction */
+#define FSCACHE_OP_KEEP_FLAGS   0x0070  /* flags to keep when repurposing an op */
 
+        enum fscache_operation_state state;
         atomic_t                usage;
         unsigned                debug_id;       /* debugging ID */
 
@@ -106,6 +116,7 @@ extern atomic_t fscache_op_debug_id;
 extern void fscache_op_work_func(struct work_struct *work);
 
 extern void fscache_enqueue_operation(struct fscache_operation *);
+extern void fscache_op_complete(struct fscache_operation *, bool);
 extern void fscache_put_operation(struct fscache_operation *);
 
 /**
@@ -122,6 +133,7 @@ static inline void fscache_operation_init(struct fscache_operation *op,
 {
         INIT_WORK(&op->work, fscache_op_work_func);
         atomic_set(&op->usage, 1);
+        op->state = FSCACHE_OP_ST_INITIALISED;
         op->debug_id = atomic_inc_return(&fscache_op_debug_id);
         op->processor = processor;
         op->release = release;
@@ -138,6 +150,7 @@ struct fscache_retrieval {
         void                    *context;       /* netfs read context (pinned) */
         struct list_head        to_do;          /* list of things to be done by the backend */
         unsigned long           start_time;     /* time at which retrieval started */
+        unsigned                n_pages;        /* number of pages to be retrieved */
 };
 
 typedef int (*fscache_page_retrieval_func_t)(struct fscache_retrieval *op,
@@ -174,8 +187,22 @@ static inline void fscache_enqueue_retrieval(struct fscache_retrieval *op)
 }
 
 /**
+ * fscache_retrieval_complete - Record (partial) completion of a retrieval
+ * @op: The retrieval operation affected
+ * @n_pages: The number of pages to account for
+ */
+static inline void fscache_retrieval_complete(struct fscache_retrieval *op,
+                                              int n_pages)
+{
+        op->n_pages -= n_pages;
+        if (op->n_pages <= 0)
+                fscache_op_complete(&op->op, true);
+}
+
+/**
  * fscache_put_retrieval - Drop a reference to a retrieval operation
  * @op: The retrieval operation affected
+ * @n_pages: The number of pages to account for
  *
  * Drop a reference to a retrieval operation.
  */
@@ -227,6 +254,9 @@ struct fscache_cache_ops {
         /* store the updated auxiliary data on an object */
         void (*update_object)(struct fscache_object *object);
 
+        /* Invalidate an object */
+        void (*invalidate_object)(struct fscache_operation *op);
+
         /* discard the resources pinned by an object and effect retirement if
          * necessary */
         void (*drop_object)(struct fscache_object *object);
@@ -301,11 +331,30 @@ struct fscache_cookie {
 #define FSCACHE_COOKIE_PENDING_FILL     3       /* T if pending initial fill on object */
 #define FSCACHE_COOKIE_FILLING          4       /* T if filling object incrementally */
 #define FSCACHE_COOKIE_UNAVAILABLE      5       /* T if cookie is unavailable (error, etc) */
+#define FSCACHE_COOKIE_WAITING_ON_READS 6       /* T if cookie is waiting on reads */
+#define FSCACHE_COOKIE_INVALIDATING     7       /* T if cookie is being invalidated */
 };
 
 extern struct fscache_cookie fscache_fsdef_index;
 
 /*
+ * Event list for fscache_object::{event_mask,events}
+ */
+enum {
+        FSCACHE_OBJECT_EV_REQUEUE,      /* T if object should be requeued */
+        FSCACHE_OBJECT_EV_UPDATE,       /* T if object should be updated */
+        FSCACHE_OBJECT_EV_INVALIDATE,   /* T if cache requested object invalidation */
+        FSCACHE_OBJECT_EV_CLEARED,      /* T if accessors all gone */
+        FSCACHE_OBJECT_EV_ERROR,        /* T if fatal error occurred during processing */
+        FSCACHE_OBJECT_EV_RELEASE,      /* T if netfs requested object release */
+        FSCACHE_OBJECT_EV_RETIRE,       /* T if netfs requested object retirement */
+        FSCACHE_OBJECT_EV_WITHDRAW,     /* T if cache requested object withdrawal */
+        NR_FSCACHE_OBJECT_EVENTS
+};
+
+#define FSCACHE_OBJECT_EVENTS_MASK ((1UL << NR_FSCACHE_OBJECT_EVENTS) - 1)
+
+/*
  * on-disk cache file or index handle
  */
 struct fscache_object {
@@ -317,6 +366,7 @@ struct fscache_object {
                 /* active states */
                 FSCACHE_OBJECT_AVAILABLE,       /* cleaning up object after creation */
                 FSCACHE_OBJECT_ACTIVE,          /* object is usable */
+                FSCACHE_OBJECT_INVALIDATING,    /* object is invalidating */
                 FSCACHE_OBJECT_UPDATING,        /* object is updating */
 
                 /* terminal states */
@@ -332,10 +382,10 @@ struct fscache_object {
 
         int                     debug_id;       /* debugging ID */
         int                     n_children;     /* number of child objects */
-        int                     n_ops;          /* number of ops outstanding on object */
+        int                     n_ops;          /* number of extant ops on object */
         int                     n_obj_ops;      /* number of object ops outstanding on object */
         int                     n_in_progress;  /* number of ops in progress */
-        int                     n_exclusive;    /* number of exclusive ops queued */
+        int                     n_exclusive;    /* number of exclusive ops queued or in progress */
         atomic_t                n_reads;        /* number of read ops in progress */
         spinlock_t              lock;           /* state and operations lock */
 
@@ -343,14 +393,6 @@ struct fscache_object {
         unsigned long           event_mask;     /* events this object is interested in */
         unsigned long           events;         /* events to be processed by this object
                                                  * (order is important - using fls) */
-#define FSCACHE_OBJECT_EV_REQUEUE       0       /* T if object should be requeued */
-#define FSCACHE_OBJECT_EV_UPDATE        1       /* T if object should be updated */
-#define FSCACHE_OBJECT_EV_CLEARED       2       /* T if accessors all gone */
-#define FSCACHE_OBJECT_EV_ERROR         3       /* T if fatal error occurred during processing */
-#define FSCACHE_OBJECT_EV_RELEASE       4       /* T if netfs requested object release */
-#define FSCACHE_OBJECT_EV_RETIRE        5       /* T if netfs requested object retirement */
-#define FSCACHE_OBJECT_EV_WITHDRAW      6       /* T if cache requested object withdrawal */
-#define FSCACHE_OBJECT_EVENTS_MASK      0x7f    /* mask of all events*/
 
         unsigned long           flags;
 #define FSCACHE_OBJECT_LOCK             0       /* T if object is busy being processed */
@@ -504,6 +546,9 @@ extern void fscache_withdraw_cache(struct fscache_cache *cache);
 
 extern void fscache_io_error(struct fscache_cache *cache);
 
+extern void fscache_mark_page_cached(struct fscache_retrieval *op,
+                                     struct page *page);
+
 extern void fscache_mark_pages_cached(struct fscache_retrieval *op,
                                       struct pagevec *pagevec);