1 files changed, 38 insertions, 2 deletions

diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index 84d3532dd3e..7be0c6fbe88 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -91,6 +91,8 @@ struct fscache_operation {
 #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 */
 
         atomic_t                usage;
         unsigned                debug_id;       /* debugging ID */
@@ -102,6 +104,16 @@ struct fscache_operation {
 
         /* operation releaser */
         fscache_operation_release_t release;
+
+#ifdef CONFIG_SLOW_WORK_PROC
+        const char *name;               /* operation name */
+        const char *state;              /* operation state */
+#define fscache_set_op_name(OP, N)      do { (OP)->name  = (N); } while(0)
+#define fscache_set_op_state(OP, S)     do { (OP)->state = (S); } while(0)
+#else
+#define fscache_set_op_name(OP, N)      do { } while(0)
+#define fscache_set_op_state(OP, S)     do { } while(0)
+#endif
 };
 
 extern atomic_t fscache_op_debug_id;
@@ -125,6 +137,7 @@ static inline void fscache_operation_init(struct fscache_operation *op,
         op->debug_id = atomic_inc_return(&fscache_op_debug_id);
         op->release = release;
         INIT_LIST_HEAD(&op->pend_link);
+        fscache_set_op_state(op, "Init");
 }
 
 /**
@@ -221,8 +234,10 @@ struct fscache_cache_ops {
         struct fscache_object *(*alloc_object)(struct fscache_cache *cache,
                                                struct fscache_cookie *cookie);
 
-        /* look up the object for a cookie */
-        void (*lookup_object)(struct fscache_object *object);
+        /* look up the object for a cookie
+         * - return -ETIMEDOUT to be requeued
+         */
+        int (*lookup_object)(struct fscache_object *object);
 
         /* finished looking up */
         void (*lookup_complete)(struct fscache_object *object);
@@ -297,12 +312,14 @@ struct fscache_cookie {
         atomic_t                        usage;          /* number of users of this cookie */
         atomic_t                        n_children;     /* number of children of this cookie */
         spinlock_t                      lock;
+        spinlock_t                      stores_lock;    /* lock on page store tree */
         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 */
         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 */
+#define FSCACHE_COOKIE_STORING_TAG      1               /* pages tag: writing to cache */
 
         unsigned long                   flags;
 #define FSCACHE_COOKIE_LOOKING_UP       0       /* T if non-index cookie being looked up still */
@@ -337,6 +354,7 @@ struct fscache_object {
                 FSCACHE_OBJECT_RECYCLING,       /* retiring object */
                 FSCACHE_OBJECT_WITHDRAWING,     /* withdrawing object */
                 FSCACHE_OBJECT_DEAD,            /* object is now dead */
+                FSCACHE_OBJECT__NSTATES
         } state;
 
         int                     debug_id;       /* debugging ID */
@@ -345,6 +363,7 @@ struct fscache_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 */
+        atomic_t                n_reads;        /* number of read ops in progress */
         spinlock_t              lock;           /* state and operations lock */
 
         unsigned long           lookup_jif;     /* time at which lookup started */
@@ -358,6 +377,7 @@ struct fscache_object {
 #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 */
@@ -373,7 +393,11 @@ struct fscache_object {
         struct list_head        dependents;     /* FIFO of dependent objects */
         struct list_head        dep_link;       /* link in parent's dependents list */
         struct list_head        pending_ops;    /* unstarted operations on this object */
+#ifdef CONFIG_FSCACHE_OBJECT_LIST
+        struct rb_node          objlist_link;   /* link in global object list */
+#endif
         pgoff_t                 store_limit;    /* current storage limit */
+        loff_t                  store_limit_l;  /* current storage limit */
 };
 
 extern const char *fscache_object_states[];
@@ -383,6 +407,10 @@ extern const char *fscache_object_states[];
          (obj)->state >= FSCACHE_OBJECT_AVAILABLE &&          \
          (obj)->state < FSCACHE_OBJECT_DYING)
 
+#define fscache_object_is_dead(obj)                             \
+        (test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) &&     \
+         (obj)->state >= FSCACHE_OBJECT_DYING)
+
 extern const struct slow_work_ops fscache_object_slow_work_ops;
 
 /**
@@ -414,6 +442,7 @@ void fscache_object_init(struct fscache_object *object,
         object->events = object->event_mask = 0;
         object->flags = 0;
         object->store_limit = 0;
+        object->store_limit_l = 0;
         object->cache = cache;
         object->cookie = cookie;
         object->parent = NULL;
@@ -422,6 +451,12 @@ void fscache_object_init(struct fscache_object *object,
 extern void fscache_object_lookup_negative(struct fscache_object *object);
 extern void fscache_obtained_object(struct fscache_object *object);
 
+#ifdef CONFIG_FSCACHE_OBJECT_LIST
+extern void fscache_object_destroy(struct fscache_object *object);
+#else
+#define fscache_object_destroy(object) do {} while(0)
+#endif
+
 /**
  * fscache_object_destroyed - Note destruction of an object in a cache
  * @cache: The cache from which the object came
@@ -460,6 +495,7 @@ static inline void fscache_object_lookup_error(struct fscache_object *object)
 static inline
 void fscache_set_store_limit(struct fscache_object *object, loff_t i_size)
 {
+        object->store_limit_l = i_size;
         object->store_limit = i_size >> PAGE_SHIFT;
         if (i_size & ~PAGE_MASK)
                 object->store_limit++;