Merge branch 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6

[pandora-kernel.git] / drivers / md / dm-table.c

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index d58b200..986b875 100644 (file)
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -540,8 +540,7 @@ int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
         * If not we'll force DM to use PAGE_SIZE or
         * smaller I/O, just to be safe.
         */
-
-       if (q->merge_bvec_fn && !ti->type->merge)
+       if (dm_queue_merge_is_compulsory(q) && !ti->type->merge)
                blk_limits_max_hw_sectors(limits,
                                          (unsigned int) (PAGE_SIZE >> 9));
        return 0;
@@ -798,6 +797,63 @@ int dm_table_add_target(struct dm_table *t, const char *type,
        return r;
 }
 
+/*
+ * Target argument parsing helpers.
+ */
+static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
+                            unsigned *value, char **error, unsigned grouped)
+{
+       const char *arg_str = dm_shift_arg(arg_set);
+
+       if (!arg_str ||
+           (sscanf(arg_str, "%u", value) != 1) ||
+           (*value < arg->min) ||
+           (*value > arg->max) ||
+           (grouped && arg_set->argc < *value)) {
+               *error = arg->error;
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
+               unsigned *value, char **error)
+{
+       return validate_next_arg(arg, arg_set, value, error, 0);
+}
+EXPORT_SYMBOL(dm_read_arg);
+
+int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set,
+                     unsigned *value, char **error)
+{
+       return validate_next_arg(arg, arg_set, value, error, 1);
+}
+EXPORT_SYMBOL(dm_read_arg_group);
+
+const char *dm_shift_arg(struct dm_arg_set *as)
+{
+       char *r;
+
+       if (as->argc) {
+               as->argc--;
+               r = *as->argv;
+               as->argv++;
+               return r;
+       }
+
+       return NULL;
+}
+EXPORT_SYMBOL(dm_shift_arg);
+
+void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
+{
+       BUG_ON(as->argc < num_args);
+       as->argc -= num_args;
+       as->argv += num_args;
+}
+EXPORT_SYMBOL(dm_consume_args);
+
 static int dm_table_set_type(struct dm_table *t)
 {
        unsigned i;
@@ -1192,9 +1248,45 @@ static void dm_table_set_integrity(struct dm_table *t)
                               blk_get_integrity(template_disk));
 }
 
+static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
+                               sector_t start, sector_t len, void *data)
+{
+       unsigned flush = (*(unsigned *)data);
+       struct request_queue *q = bdev_get_queue(dev->bdev);
+
+       return q && (q->flush_flags & flush);
+}
+
+static bool dm_table_supports_flush(struct dm_table *t, unsigned flush)
+{
+       struct dm_target *ti;
+       unsigned i = 0;
+
+       /*
+        * Require at least one underlying device to support flushes.
+        * t->devices includes internal dm devices such as mirror logs
+        * so we need to use iterate_devices here, which targets
+        * supporting flushes must provide.
+        */
+       while (i < dm_table_get_num_targets(t)) {
+               ti = dm_table_get_target(t, i++);
+
+               if (!ti->num_flush_requests)
+                       continue;
+
+               if (ti->type->iterate_devices &&
+                   ti->type->iterate_devices(ti, device_flush_capable, &flush))
+                       return 1;
+       }
+
+       return 0;
+}
+
 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
                               struct queue_limits *limits)
 {
+       unsigned flush = 0;
+
        /*
         * Copy table's limits to the DM device's request_queue
         */
@@ -1205,6 +1297,13 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
        else
                queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
 
+       if (dm_table_supports_flush(t, REQ_FLUSH)) {
+               flush |= REQ_FLUSH;
+               if (dm_table_supports_flush(t, REQ_FUA))
+                       flush |= REQ_FUA;
+       }
+       blk_queue_flush(q, flush);
+
        dm_table_set_integrity(t);
 
        /*