ARM: tegra: ardbeg: set avg values for productized sensors
[linux-3.10.git] / block / blk-core.c
index 277134c..d5745b5 100644 (file)
@@ -30,6 +30,7 @@
 #include <linux/list_sort.h>
 #include <linux/delay.h>
 #include <linux/ratelimit.h>
+#include <linux/pm_runtime.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/block.h>
@@ -159,20 +160,10 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
        else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
                error = -EIO;
 
-       if (unlikely(nbytes > bio->bi_size)) {
-               printk(KERN_ERR "%s: want %u bytes done, %u left\n",
-                      __func__, nbytes, bio->bi_size);
-               nbytes = bio->bi_size;
-       }
-
        if (unlikely(rq->cmd_flags & REQ_QUIET))
                set_bit(BIO_QUIET, &bio->bi_flags);
 
-       bio->bi_size -= nbytes;
-       bio->bi_sector += (nbytes >> 9);
-
-       if (bio_integrity(bio))
-               bio_integrity_advance(bio, nbytes);
+       bio_advance(bio, nbytes);
 
        /* don't actually finish bio if it's part of flush sequence */
        if (bio->bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ))
@@ -1264,6 +1255,16 @@ void part_round_stats(int cpu, struct hd_struct *part)
 }
 EXPORT_SYMBOL_GPL(part_round_stats);
 
+#ifdef CONFIG_PM_RUNTIME
+static void blk_pm_put_request(struct request *rq)
+{
+       if (rq->q->dev && !(rq->cmd_flags & REQ_PM) && !--rq->q->nr_pending)
+               pm_runtime_mark_last_busy(rq->q->dev);
+}
+#else
+static inline void blk_pm_put_request(struct request *rq) {}
+#endif
+
 /*
  * queue lock must be held
  */
@@ -1274,6 +1275,8 @@ void __blk_put_request(struct request_queue *q, struct request *req)
        if (unlikely(--req->ref_count))
                return;
 
+       blk_pm_put_request(req);
+
        elv_completed_request(q, req);
 
        /* this is a bio leak */
@@ -1348,7 +1351,7 @@ static bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
        if (!ll_back_merge_fn(q, req, bio))
                return false;
 
-       trace_block_bio_backmerge(q, bio);
+       trace_block_bio_backmerge(q, req, bio);
 
        if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
                blk_rq_set_mixed_merge(req);
@@ -1370,7 +1373,7 @@ static bool bio_attempt_front_merge(struct request_queue *q,
        if (!ll_front_merge_fn(q, req, bio))
                return false;
 
-       trace_block_bio_frontmerge(q, bio);
+       trace_block_bio_frontmerge(q, req, bio);
 
        if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
                blk_rq_set_mixed_merge(req);
@@ -1553,13 +1556,6 @@ get_rq:
                if (list_empty(&plug->list))
                        trace_block_plug(q);
                else {
-                       if (!plug->should_sort) {
-                               struct request *__rq;
-
-                               __rq = list_entry_rq(plug->list.prev);
-                               if (__rq->q != q)
-                                       plug->should_sort = 1;
-                       }
                        if (request_count >= BLK_MAX_REQUEST_COUNT) {
                                blk_flush_plug_list(plug, false);
                                trace_block_plug(q);
@@ -1604,7 +1600,7 @@ static void handle_bad_sector(struct bio *bio)
        printk(KERN_INFO "%s: rw=%ld, want=%Lu, limit=%Lu\n",
                        bdevname(bio->bi_bdev, b),
                        bio->bi_rw,
-                       (unsigned long long)bio->bi_sector + bio_sectors(bio),
+                       (unsigned long long)bio_end_sector(bio),
                        (long long)(i_size_read(bio->bi_bdev->bd_inode) >> 9));
 
        set_bit(BIO_EOF, &bio->bi_flags);
@@ -2060,6 +2056,28 @@ static void blk_account_io_done(struct request *req)
        }
 }
 
+#ifdef CONFIG_PM_RUNTIME
+/*
+ * Don't process normal requests when queue is suspended
+ * or in the process of suspending/resuming
+ */
+static struct request *blk_pm_peek_request(struct request_queue *q,
+                                          struct request *rq)
+{
+       if (q->dev && (q->rpm_status == RPM_SUSPENDED ||
+           (q->rpm_status != RPM_ACTIVE && !(rq->cmd_flags & REQ_PM))))
+               return NULL;
+       else
+               return rq;
+}
+#else
+static inline struct request *blk_pm_peek_request(struct request_queue *q,
+                                                 struct request *rq)
+{
+       return rq;
+}
+#endif
+
 /**
  * blk_peek_request - peek at the top of a request queue
  * @q: request queue to peek at
@@ -2082,6 +2100,11 @@ struct request *blk_peek_request(struct request_queue *q)
        int ret;
 
        while ((rq = __elv_next_request(q)) != NULL) {
+
+               rq = blk_pm_peek_request(q, rq);
+               if (!rq)
+                       break;
+
                if (!(rq->cmd_flags & REQ_STARTED)) {
                        /*
                         * This is the first time the device driver
@@ -2260,8 +2283,7 @@ EXPORT_SYMBOL(blk_fetch_request);
  **/
 bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 {
-       int total_bytes, bio_nbytes, next_idx = 0;
-       struct bio *bio;
+       int total_bytes;
 
        if (!req->bio)
                return false;
@@ -2307,56 +2329,21 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 
        blk_account_io_completion(req, nr_bytes);
 
-       total_bytes = bio_nbytes = 0;
-       while ((bio = req->bio) != NULL) {
-               int nbytes;
+       total_bytes = 0;
+       while (req->bio) {
+               struct bio *bio = req->bio;
+               unsigned bio_bytes = min(bio->bi_size, nr_bytes);
 
-               if (nr_bytes >= bio->bi_size) {
+               if (bio_bytes == bio->bi_size)
                        req->bio = bio->bi_next;
-                       nbytes = bio->bi_size;
-                       req_bio_endio(req, bio, nbytes, error);
-                       next_idx = 0;
-                       bio_nbytes = 0;
-               } else {
-                       int idx = bio->bi_idx + next_idx;
 
-                       if (unlikely(idx >= bio->bi_vcnt)) {
-                               blk_dump_rq_flags(req, "__end_that");
-                               printk(KERN_ERR "%s: bio idx %d >= vcnt %d\n",
-                                      __func__, idx, bio->bi_vcnt);
-                               break;
-                       }
-
-                       nbytes = bio_iovec_idx(bio, idx)->bv_len;
-                       BIO_BUG_ON(nbytes > bio->bi_size);
-
-                       /*
-                        * not a complete bvec done
-                        */
-                       if (unlikely(nbytes > nr_bytes)) {
-                               bio_nbytes += nr_bytes;
-                               total_bytes += nr_bytes;
-                               break;
-                       }
+               req_bio_endio(req, bio, bio_bytes, error);
 
-                       /*
-                        * advance to the next vector
-                        */
-                       next_idx++;
-                       bio_nbytes += nbytes;
-               }
-
-               total_bytes += nbytes;
-               nr_bytes -= nbytes;
+               total_bytes += bio_bytes;
+               nr_bytes -= bio_bytes;
 
-               bio = req->bio;
-               if (bio) {
-                       /*
-                        * end more in this run, or just return 'not-done'
-                        */
-                       if (unlikely(nr_bytes <= 0))
-                               break;
-               }
+               if (!nr_bytes)
+                       break;
        }
 
        /*
@@ -2372,16 +2359,6 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
                return false;
        }
 
-       /*
-        * if the request wasn't completed, update state
-        */
-       if (bio_nbytes) {
-               req_bio_endio(req, bio, bio_nbytes, error);
-               bio->bi_idx += next_idx;
-               bio_iovec(bio)->bv_offset += nr_bytes;
-               bio_iovec(bio)->bv_len -= nr_bytes;
-       }
-
        req->__data_len -= total_bytes;
        req->buffer = bio_data(req->bio);
 
@@ -2890,7 +2867,6 @@ void blk_start_plug(struct blk_plug *plug)
        plug->magic = PLUG_MAGIC;
        INIT_LIST_HEAD(&plug->list);
        INIT_LIST_HEAD(&plug->cb_list);
-       plug->should_sort = 0;
 
        /*
         * If this is a nested plug, don't actually assign it. It will be
@@ -2992,10 +2968,7 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 
        list_splice_init(&plug->list, &list);
 
-       if (plug->should_sort) {
-               list_sort(NULL, &list, plug_rq_cmp);
-               plug->should_sort = 0;
-       }
+       list_sort(NULL, &list, plug_rq_cmp);
 
        q = NULL;
        depth = 0;
@@ -3057,6 +3030,149 @@ void blk_finish_plug(struct blk_plug *plug)
 }
 EXPORT_SYMBOL(blk_finish_plug);
 
+#ifdef CONFIG_PM_RUNTIME
+/**
+ * blk_pm_runtime_init - Block layer runtime PM initialization routine
+ * @q: the queue of the device
+ * @dev: the device the queue belongs to
+ *
+ * Description:
+ *    Initialize runtime-PM-related fields for @q and start auto suspend for
+ *    @dev. Drivers that want to take advantage of request-based runtime PM
+ *    should call this function after @dev has been initialized, and its
+ *    request queue @q has been allocated, and runtime PM for it can not happen
+ *    yet(either due to disabled/forbidden or its usage_count > 0). In most
+ *    cases, driver should call this function before any I/O has taken place.
+ *
+ *    This function takes care of setting up using auto suspend for the device,
+ *    the autosuspend delay is set to -1 to make runtime suspend impossible
+ *    until an updated value is either set by user or by driver. Drivers do
+ *    not need to touch other autosuspend settings.
+ *
+ *    The block layer runtime PM is request based, so only works for drivers
+ *    that use request as their IO unit instead of those directly use bio's.
+ */
+void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
+{
+       q->dev = dev;
+       q->rpm_status = RPM_ACTIVE;
+       pm_runtime_set_autosuspend_delay(q->dev, -1);
+       pm_runtime_use_autosuspend(q->dev);
+}
+EXPORT_SYMBOL(blk_pm_runtime_init);
+
+/**
+ * blk_pre_runtime_suspend - Pre runtime suspend check
+ * @q: the queue of the device
+ *
+ * Description:
+ *    This function will check if runtime suspend is allowed for the device
+ *    by examining if there are any requests pending in the queue. If there
+ *    are requests pending, the device can not be runtime suspended; otherwise,
+ *    the queue's status will be updated to SUSPENDING and the driver can
+ *    proceed to suspend the device.
+ *
+ *    For the not allowed case, we mark last busy for the device so that
+ *    runtime PM core will try to autosuspend it some time later.
+ *
+ *    This function should be called near the start of the device's
+ *    runtime_suspend callback.
+ *
+ * Return:
+ *    0                - OK to runtime suspend the device
+ *    -EBUSY   - Device should not be runtime suspended
+ */
+int blk_pre_runtime_suspend(struct request_queue *q)
+{
+       int ret = 0;
+
+       spin_lock_irq(q->queue_lock);
+       if (q->nr_pending) {
+               ret = -EBUSY;
+               pm_runtime_mark_last_busy(q->dev);
+       } else {
+               q->rpm_status = RPM_SUSPENDING;
+       }
+       spin_unlock_irq(q->queue_lock);
+       return ret;
+}
+EXPORT_SYMBOL(blk_pre_runtime_suspend);
+
+/**
+ * blk_post_runtime_suspend - Post runtime suspend processing
+ * @q: the queue of the device
+ * @err: return value of the device's runtime_suspend function
+ *
+ * Description:
+ *    Update the queue's runtime status according to the return value of the
+ *    device's runtime suspend function and mark last busy for the device so
+ *    that PM core will try to auto suspend the device at a later time.
+ *
+ *    This function should be called near the end of the device's
+ *    runtime_suspend callback.
+ */
+void blk_post_runtime_suspend(struct request_queue *q, int err)
+{
+       spin_lock_irq(q->queue_lock);
+       if (!err) {
+               q->rpm_status = RPM_SUSPENDED;
+       } else {
+               q->rpm_status = RPM_ACTIVE;
+               pm_runtime_mark_last_busy(q->dev);
+       }
+       spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_post_runtime_suspend);
+
+/**
+ * blk_pre_runtime_resume - Pre runtime resume processing
+ * @q: the queue of the device
+ *
+ * Description:
+ *    Update the queue's runtime status to RESUMING in preparation for the
+ *    runtime resume of the device.
+ *
+ *    This function should be called near the start of the device's
+ *    runtime_resume callback.
+ */
+void blk_pre_runtime_resume(struct request_queue *q)
+{
+       spin_lock_irq(q->queue_lock);
+       q->rpm_status = RPM_RESUMING;
+       spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_pre_runtime_resume);
+
+/**
+ * blk_post_runtime_resume - Post runtime resume processing
+ * @q: the queue of the device
+ * @err: return value of the device's runtime_resume function
+ *
+ * Description:
+ *    Update the queue's runtime status according to the return value of the
+ *    device's runtime_resume function. If it is successfully resumed, process
+ *    the requests that are queued into the device's queue when it is resuming
+ *    and then mark last busy and initiate autosuspend for it.
+ *
+ *    This function should be called near the end of the device's
+ *    runtime_resume callback.
+ */
+void blk_post_runtime_resume(struct request_queue *q, int err)
+{
+       spin_lock_irq(q->queue_lock);
+       if (!err) {
+               q->rpm_status = RPM_ACTIVE;
+               __blk_run_queue(q);
+               pm_runtime_mark_last_busy(q->dev);
+               pm_request_autosuspend(q->dev);
+       } else {
+               q->rpm_status = RPM_SUSPENDED;
+       }
+       spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_post_runtime_resume);
+#endif
+
 int __init blk_dev_init(void)
 {
        BUILD_BUG_ON(__REQ_NR_BITS > 8 *