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-rw-r--r--block/blk-barrier.c2
-rw-r--r--block/blk-ioc.c5
-rw-r--r--block/blk-settings.c140
-rw-r--r--block/cfq-iosched.c73
-rw-r--r--block/genhd.c2
5 files changed, 131 insertions, 91 deletions
diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 8873b9b439f..8618d8996fe 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -402,7 +402,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
* our current implementations need. If we'll ever need
* more the interface will need revisiting.
*/
- page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ page = alloc_page(gfp_mask | __GFP_ZERO);
if (!page)
goto out_free_bio;
if (bio_add_pc_page(q, bio, page, sector_size, 0) < sector_size)
diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index cbdabb0dd6d..98e6bf61b0a 100644
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -39,8 +39,6 @@ int put_io_context(struct io_context *ioc)
if (atomic_long_dec_and_test(&ioc->refcount)) {
rcu_read_lock();
- if (ioc->aic && ioc->aic->dtor)
- ioc->aic->dtor(ioc->aic);
cfq_dtor(ioc);
rcu_read_unlock();
@@ -76,8 +74,6 @@ void exit_io_context(struct task_struct *task)
task_unlock(task);
if (atomic_dec_and_test(&ioc->nr_tasks)) {
- if (ioc->aic && ioc->aic->exit)
- ioc->aic->exit(ioc->aic);
cfq_exit(ioc);
}
@@ -97,7 +93,6 @@ struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
ret->ioprio = 0;
ret->last_waited = jiffies; /* doesn't matter... */
ret->nr_batch_requests = 0; /* because this is 0 */
- ret->aic = NULL;
INIT_RADIX_TREE(&ret->radix_root, GFP_ATOMIC | __GFP_HIGH);
INIT_HLIST_HEAD(&ret->cic_list);
ret->ioc_data = NULL;
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 6ae118d6e19..5eeb9e0d256 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -505,21 +505,30 @@ static unsigned int lcm(unsigned int a, unsigned int b)
/**
* blk_stack_limits - adjust queue_limits for stacked devices
- * @t: the stacking driver limits (top)
- * @b: the underlying queue limits (bottom)
+ * @t: the stacking driver limits (top device)
+ * @b: the underlying queue limits (bottom, component device)
* @offset: offset to beginning of data within component device
*
* Description:
- * Merges two queue_limit structs. Returns 0 if alignment didn't
- * change. Returns -1 if adding the bottom device caused
- * misalignment.
+ * This function is used by stacking drivers like MD and DM to ensure
+ * that all component devices have compatible block sizes and
+ * alignments. The stacking driver must provide a queue_limits
+ * struct (top) and then iteratively call the stacking function for
+ * all component (bottom) devices. The stacking function will
+ * attempt to combine the values and ensure proper alignment.
+ *
+ * Returns 0 if the top and bottom queue_limits are compatible. The
+ * top device's block sizes and alignment offsets may be adjusted to
+ * ensure alignment with the bottom device. If no compatible sizes
+ * and alignments exist, -1 is returned and the resulting top
+ * queue_limits will have the misaligned flag set to indicate that
+ * the alignment_offset is undefined.
*/
int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
sector_t offset)
{
- int ret;
-
- ret = 0;
+ sector_t alignment;
+ unsigned int top, bottom, ret = 0;
t->max_sectors = min_not_zero(t->max_sectors, b->max_sectors);
t->max_hw_sectors = min_not_zero(t->max_hw_sectors, b->max_hw_sectors);
@@ -537,6 +546,26 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
t->max_segment_size = min_not_zero(t->max_segment_size,
b->max_segment_size);
+ t->misaligned |= b->misaligned;
+
+ alignment = queue_limit_alignment_offset(b, offset);
+
+ /* Bottom device has different alignment. Check that it is
+ * compatible with the current top alignment.
+ */
+ if (t->alignment_offset != alignment) {
+
+ top = max(t->physical_block_size, t->io_min)
+ + t->alignment_offset;
+ bottom = max(b->physical_block_size, b->io_min) + alignment;
+
+ /* Verify that top and bottom intervals line up */
+ if (max(top, bottom) & (min(top, bottom) - 1)) {
+ t->misaligned = 1;
+ ret = -1;
+ }
+ }
+
t->logical_block_size = max(t->logical_block_size,
b->logical_block_size);
@@ -544,58 +573,95 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
b->physical_block_size);
t->io_min = max(t->io_min, b->io_min);
+ t->io_opt = lcm(t->io_opt, b->io_opt);
+
t->no_cluster |= b->no_cluster;
t->discard_zeroes_data &= b->discard_zeroes_data;
- /* Bottom device offset aligned? */
- if (offset &&
- (offset & (b->physical_block_size - 1)) != b->alignment_offset) {
+ /* Physical block size a multiple of the logical block size? */
+ if (t->physical_block_size & (t->logical_block_size - 1)) {
+ t->physical_block_size = t->logical_block_size;
t->misaligned = 1;
ret = -1;
}
- /*
- * Temporarily disable discard granularity. It's currently buggy
- * since we default to 0 for discard_granularity, hence this
- * "failure" will always trigger for non-zero offsets.
- */
-#if 0
- if (offset &&
- (offset & (b->discard_granularity - 1)) != b->discard_alignment) {
- t->discard_misaligned = 1;
+ /* Minimum I/O a multiple of the physical block size? */
+ if (t->io_min & (t->physical_block_size - 1)) {
+ t->io_min = t->physical_block_size;
+ t->misaligned = 1;
ret = -1;
}
-#endif
- /* If top has no alignment offset, inherit from bottom */
- if (!t->alignment_offset)
- t->alignment_offset =
- b->alignment_offset & (b->physical_block_size - 1);
+ /* Optimal I/O a multiple of the physical block size? */
+ if (t->io_opt & (t->physical_block_size - 1)) {
+ t->io_opt = 0;
+ t->misaligned = 1;
+ ret = -1;
+ }
- if (!t->discard_alignment)
- t->discard_alignment =
- b->discard_alignment & (b->discard_granularity - 1);
+ /* Find lowest common alignment_offset */
+ t->alignment_offset = lcm(t->alignment_offset, alignment)
+ & (max(t->physical_block_size, t->io_min) - 1);
- /* Top device aligned on logical block boundary? */
+ /* Verify that new alignment_offset is on a logical block boundary */
if (t->alignment_offset & (t->logical_block_size - 1)) {
t->misaligned = 1;
ret = -1;
}
- /* Find lcm() of optimal I/O size and granularity */
- t->io_opt = lcm(t->io_opt, b->io_opt);
- t->discard_granularity = lcm(t->discard_granularity,
- b->discard_granularity);
-
- /* Verify that optimal I/O size is a multiple of io_min */
- if (t->io_min && t->io_opt % t->io_min)
- ret = -1;
+ /* Discard alignment and granularity */
+ if (b->discard_granularity) {
+ unsigned int granularity = b->discard_granularity;
+ offset &= granularity - 1;
+
+ alignment = (granularity + b->discard_alignment - offset)
+ & (granularity - 1);
+
+ if (t->discard_granularity != 0 &&
+ t->discard_alignment != alignment) {
+ top = t->discard_granularity + t->discard_alignment;
+ bottom = b->discard_granularity + alignment;
+
+ /* Verify that top and bottom intervals line up */
+ if (max(top, bottom) & (min(top, bottom) - 1))
+ t->discard_misaligned = 1;
+ }
+
+ t->max_discard_sectors = min_not_zero(t->max_discard_sectors,
+ b->max_discard_sectors);
+ t->discard_granularity = max(t->discard_granularity,
+ b->discard_granularity);
+ t->discard_alignment = lcm(t->discard_alignment, alignment) &
+ (t->discard_granularity - 1);
+ }
return ret;
}
EXPORT_SYMBOL(blk_stack_limits);
/**
+ * bdev_stack_limits - adjust queue limits for stacked drivers
+ * @t: the stacking driver limits (top device)
+ * @bdev: the component block_device (bottom)
+ * @start: first data sector within component device
+ *
+ * Description:
+ * Merges queue limits for a top device and a block_device. Returns
+ * 0 if alignment didn't change. Returns -1 if adding the bottom
+ * device caused misalignment.
+ */
+int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
+ sector_t start)
+{
+ struct request_queue *bq = bdev_get_queue(bdev);
+
+ start += get_start_sect(bdev);
+
+ return blk_stack_limits(t, &bq->limits, start << 9);
+}
+EXPORT_SYMBOL(bdev_stack_limits);
+
+/**
* disk_stack_limits - adjust queue limits for stacked drivers
* @disk: MD/DM gendisk (top)
* @bdev: the underlying block device (bottom)
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index e2f80463ed0..ee130f14d1f 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -208,8 +208,6 @@ struct cfq_data {
/* Root service tree for cfq_groups */
struct cfq_rb_root grp_service_tree;
struct cfq_group root_group;
- /* Number of active cfq groups on group service tree */
- int nr_groups;
/*
* The priority currently being served
@@ -294,8 +292,7 @@ static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd);
static struct cfq_rb_root *service_tree_for(struct cfq_group *cfqg,
enum wl_prio_t prio,
- enum wl_type_t type,
- struct cfq_data *cfqd)
+ enum wl_type_t type)
{
if (!cfqg)
return NULL;
@@ -842,7 +839,6 @@ cfq_group_service_tree_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
__cfq_group_service_tree_add(st, cfqg);
cfqg->on_st = true;
- cfqd->nr_groups++;
st->total_weight += cfqg->weight;
}
@@ -863,7 +859,6 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
cfq_log_cfqg(cfqd, cfqg, "del_from_rr group");
cfqg->on_st = false;
- cfqd->nr_groups--;
st->total_weight -= cfqg->weight;
if (!RB_EMPTY_NODE(&cfqg->rb_node))
cfq_rb_erase(&cfqg->rb_node, st);
@@ -1150,7 +1145,7 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
#endif
service_tree = service_tree_for(cfqq->cfqg, cfqq_prio(cfqq),
- cfqq_type(cfqq), cfqd);
+ cfqq_type(cfqq));
if (cfq_class_idle(cfqq)) {
rb_key = CFQ_IDLE_DELAY;
parent = rb_last(&service_tree->rb);
@@ -1513,9 +1508,6 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
struct cfq_io_context *cic;
struct cfq_queue *cfqq;
- /* Deny merge if bio and rq don't belong to same cfq group */
- if ((RQ_CFQQ(rq))->cfqg != cfq_get_cfqg(cfqd, 0))
- return false;
/*
* Disallow merge of a sync bio into an async request.
*/
@@ -1616,7 +1608,7 @@ static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd)
{
struct cfq_rb_root *service_tree =
service_tree_for(cfqd->serving_group, cfqd->serving_prio,
- cfqd->serving_type, cfqd);
+ cfqd->serving_type);
if (!cfqd->rq_queued)
return NULL;
@@ -1675,13 +1667,17 @@ static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd,
#define CFQQ_SEEKY(cfqq) ((cfqq)->seek_mean > CFQQ_SEEK_THR)
static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq,
- struct request *rq)
+ struct request *rq, bool for_preempt)
{
sector_t sdist = cfqq->seek_mean;
if (!sample_valid(cfqq->seek_samples))
sdist = CFQQ_SEEK_THR;
+ /* if seek_mean is big, using it as close criteria is meaningless */
+ if (sdist > CFQQ_SEEK_THR && !for_preempt)
+ sdist = CFQQ_SEEK_THR;
+
return cfq_dist_from_last(cfqd, rq) <= sdist;
}
@@ -1709,7 +1705,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
* will contain the closest sector.
*/
__cfqq = rb_entry(parent, struct cfq_queue, p_node);
- if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
+ if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false))
return __cfqq;
if (blk_rq_pos(__cfqq->next_rq) < sector)
@@ -1720,7 +1716,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
return NULL;
__cfqq = rb_entry(node, struct cfq_queue, p_node);
- if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
+ if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false))
return __cfqq;
return NULL;
@@ -1963,8 +1959,7 @@ static void cfq_setup_merge(struct cfq_queue *cfqq, struct cfq_queue *new_cfqq)
}
static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
- struct cfq_group *cfqg, enum wl_prio_t prio,
- bool prio_changed)
+ struct cfq_group *cfqg, enum wl_prio_t prio)
{
struct cfq_queue *queue;
int i;
@@ -1972,24 +1967,9 @@ static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
unsigned long lowest_key = 0;
enum wl_type_t cur_best = SYNC_NOIDLE_WORKLOAD;
- if (prio_changed) {
- /*
- * When priorities switched, we prefer starting
- * from SYNC_NOIDLE (first choice), or just SYNC
- * over ASYNC
- */
- if (service_tree_for(cfqg, prio, cur_best, cfqd)->count)
- return cur_best;
- cur_best = SYNC_WORKLOAD;
- if (service_tree_for(cfqg, prio, cur_best, cfqd)->count)
- return cur_best;
-
- return ASYNC_WORKLOAD;
- }
-
- for (i = 0; i < 3; ++i) {
- /* otherwise, select the one with lowest rb_key */
- queue = cfq_rb_first(service_tree_for(cfqg, prio, i, cfqd));
+ for (i = 0; i <= SYNC_WORKLOAD; ++i) {
+ /* select the one with lowest rb_key */
+ queue = cfq_rb_first(service_tree_for(cfqg, prio, i));
if (queue &&
(!key_valid || time_before(queue->rb_key, lowest_key))) {
lowest_key = queue->rb_key;
@@ -2003,8 +1983,6 @@ static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
{
- enum wl_prio_t previous_prio = cfqd->serving_prio;
- bool prio_changed;
unsigned slice;
unsigned count;
struct cfq_rb_root *st;
@@ -2032,24 +2010,19 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
* (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload
* expiration time
*/
- prio_changed = (cfqd->serving_prio != previous_prio);
- st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type,
- cfqd);
+ st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type);
count = st->count;
/*
- * If priority didn't change, check workload expiration,
- * and that we still have other queues ready
+ * check workload expiration, and that we still have other queues ready
*/
- if (!prio_changed && count &&
- !time_after(jiffies, cfqd->workload_expires))
+ if (count && !time_after(jiffies, cfqd->workload_expires))
return;
/* otherwise select new workload type */
cfqd->serving_type =
- cfq_choose_wl(cfqd, cfqg, cfqd->serving_prio, prio_changed);
- st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type,
- cfqd);
+ cfq_choose_wl(cfqd, cfqg, cfqd->serving_prio);
+ st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type);
count = st->count;
/*
@@ -3104,6 +3077,12 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
return true;
/*
+ * Don't allow a non-RT request to preempt an ongoing RT cfqq timeslice.
+ */
+ if (cfq_class_rt(cfqq) && !cfq_class_rt(new_cfqq))
+ return false;
+
+ /*
* if the new request is sync, but the currently running queue is
* not, let the sync request have priority.
*/
@@ -3143,7 +3122,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
* if this request is as-good as one we would expect from the
* current cfqq, let it preempt
*/
- if (cfq_rq_close(cfqd, cfqq, rq))
+ if (cfq_rq_close(cfqd, cfqq, rq, true))
return true;
return false;
diff --git a/block/genhd.c b/block/genhd.c
index b11a4ad7d57..d13ba76a169 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -867,7 +867,7 @@ static ssize_t disk_discard_alignment_show(struct device *dev,
{
struct gendisk *disk = dev_to_disk(dev);
- return sprintf(buf, "%u\n", queue_discard_alignment(disk->queue));
+ return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
}
static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);