Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
Linus Torvalds [Sat, 3 Nov 2007 19:43:36 +0000 (12:43 -0700)]
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  [BLOCK] Don't allow empty barriers to be passed down to queues that don't grok them
  dm: bounce_pfn limit added
  Deadline iosched: Fix batching fairness
  Deadline iosched: Reset batch for ordered requests
  Deadline iosched: Factor out finding latter reques

block/deadline-iosched.c
block/ll_rw_blk.c
drivers/md/dm-table.c
include/linux/device-mapper.h

index 1a511ff..a054eef 100644 (file)
@@ -55,6 +55,20 @@ static void deadline_move_request(struct deadline_data *, struct request *);
 
 #define RQ_RB_ROOT(dd, rq)     (&(dd)->sort_list[rq_data_dir((rq))])
 
+/*
+ * get the request after `rq' in sector-sorted order
+ */
+static inline struct request *
+deadline_latter_request(struct request *rq)
+{
+       struct rb_node *node = rb_next(&rq->rb_node);
+
+       if (node)
+               return rb_entry_rq(node);
+
+       return NULL;
+}
+
 static void
 deadline_add_rq_rb(struct deadline_data *dd, struct request *rq)
 {
@@ -74,13 +88,8 @@ deadline_del_rq_rb(struct deadline_data *dd, struct request *rq)
 {
        const int data_dir = rq_data_dir(rq);
 
-       if (dd->next_rq[data_dir] == rq) {
-               struct rb_node *rbnext = rb_next(&rq->rb_node);
-
-               dd->next_rq[data_dir] = NULL;
-               if (rbnext)
-                       dd->next_rq[data_dir] = rb_entry_rq(rbnext);
-       }
+       if (dd->next_rq[data_dir] == rq)
+               dd->next_rq[data_dir] = deadline_latter_request(rq);
 
        elv_rb_del(RQ_RB_ROOT(dd, rq), rq);
 }
@@ -198,14 +207,11 @@ static void
 deadline_move_request(struct deadline_data *dd, struct request *rq)
 {
        const int data_dir = rq_data_dir(rq);
-       struct rb_node *rbnext = rb_next(&rq->rb_node);
 
        dd->next_rq[READ] = NULL;
        dd->next_rq[WRITE] = NULL;
+       dd->next_rq[data_dir] = deadline_latter_request(rq);
 
-       if (rbnext)
-               dd->next_rq[data_dir] = rb_entry_rq(rbnext);
-       
        dd->last_sector = rq->sector + rq->nr_sectors;
 
        /*
@@ -301,30 +307,23 @@ dispatch_find_request:
        /*
         * we are not running a batch, find best request for selected data_dir
         */
-       if (deadline_check_fifo(dd, data_dir)) {
-               /* An expired request exists - satisfy it */
-               dd->batching = 0;
+       if (deadline_check_fifo(dd, data_dir) || !dd->next_rq[data_dir]) {
+               /*
+                * A deadline has expired, the last request was in the other
+                * direction, or we have run out of higher-sectored requests.
+                * Start again from the request with the earliest expiry time.
+                */
                rq = rq_entry_fifo(dd->fifo_list[data_dir].next);
-               
-       } else if (dd->next_rq[data_dir]) {
+       } else {
                /*
                 * The last req was the same dir and we have a next request in
                 * sort order. No expired requests so continue on from here.
                 */
                rq = dd->next_rq[data_dir];
-       } else {
-               struct rb_node *node;
-               /*
-                * The last req was the other direction or we have run out of
-                * higher-sectored requests. Go back to the lowest sectored
-                * request (1 way elevator) and start a new batch.
-                */
-               dd->batching = 0;
-               node = rb_first(&dd->sort_list[data_dir]);
-               if (node)
-                       rq = rb_entry_rq(node);
        }
 
+       dd->batching = 0;
+
 dispatch_request:
        /*
         * rq is the selected appropriate request.
index 54fd385..75c98d5 100644 (file)
@@ -3221,6 +3221,7 @@ static inline void __generic_make_request(struct bio *bio)
        sector_t old_sector;
        int ret, nr_sectors = bio_sectors(bio);
        dev_t old_dev;
+       int err = -EIO;
 
        might_sleep();
 
@@ -3248,7 +3249,7 @@ static inline void __generic_make_request(struct bio *bio)
                                bdevname(bio->bi_bdev, b),
                                (long long) bio->bi_sector);
 end_io:
-                       bio_endio(bio, -EIO);
+                       bio_endio(bio, err);
                        break;
                }
 
@@ -3283,6 +3284,10 @@ end_io:
 
                if (bio_check_eod(bio, nr_sectors))
                        goto end_io;
+               if (bio_empty_barrier(bio) && !q->prepare_flush_fn) {
+                       err = -EOPNOTSUPP;
+                       goto end_io;
+               }
 
                ret = q->make_request_fn(q, bio);
        } while (ret);
index 8939e61..5a7eb65 100644 (file)
@@ -102,6 +102,8 @@ static void combine_restrictions_low(struct io_restrictions *lhs,
        lhs->seg_boundary_mask =
                min_not_zero(lhs->seg_boundary_mask, rhs->seg_boundary_mask);
 
+       lhs->bounce_pfn = min_not_zero(lhs->bounce_pfn, rhs->bounce_pfn);
+
        lhs->no_cluster |= rhs->no_cluster;
 }
 
@@ -566,6 +568,8 @@ void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
                min_not_zero(rs->seg_boundary_mask,
                             q->seg_boundary_mask);
 
+       rs->bounce_pfn = min_not_zero(rs->bounce_pfn, q->bounce_pfn);
+
        rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
 }
 EXPORT_SYMBOL_GPL(dm_set_device_limits);
@@ -707,6 +711,8 @@ static void check_for_valid_limits(struct io_restrictions *rs)
                rs->max_segment_size = MAX_SEGMENT_SIZE;
        if (!rs->seg_boundary_mask)
                rs->seg_boundary_mask = -1;
+       if (!rs->bounce_pfn)
+               rs->bounce_pfn = -1;
 }
 
 int dm_table_add_target(struct dm_table *t, const char *type,
@@ -891,6 +897,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q)
        q->hardsect_size = t->limits.hardsect_size;
        q->max_segment_size = t->limits.max_segment_size;
        q->seg_boundary_mask = t->limits.seg_boundary_mask;
+       q->bounce_pfn = t->limits.bounce_pfn;
        if (t->limits.no_cluster)
                q->queue_flags &= ~(1 << QUEUE_FLAG_CLUSTER);
        else
index 37c66d1..b8b7c51 100644 (file)
@@ -116,6 +116,7 @@ struct io_restrictions {
        unsigned short          hardsect_size;
        unsigned int            max_segment_size;
        unsigned long           seg_boundary_mask;
+       unsigned long           bounce_pfn;
        unsigned char           no_cluster; /* inverted so that 0 is default */
 };