#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/writeback.h>
+#include <linux/interrupt.h>
+#include <linux/cpu.h>
+#include <linux/blktrace_api.h>
/*
* for max sense size
/*
* Controlling structure to kblockd
*/
-static struct workqueue_struct *kblockd_workqueue;
+static struct workqueue_struct *kblockd_workqueue;
unsigned long blk_max_low_pfn, blk_max_pfn;
EXPORT_SYMBOL(blk_max_low_pfn);
EXPORT_SYMBOL(blk_max_pfn);
+static DEFINE_PER_CPU(struct list_head, blk_cpu_done);
+
/* Amount of time in which a process may batch requests */
#define BLK_BATCH_TIME (HZ/50UL)
EXPORT_SYMBOL(blk_queue_merge_bvec);
+void blk_queue_softirq_done(request_queue_t *q, softirq_done_fn *fn)
+{
+ q->softirq_done_fn = fn;
+}
+
+EXPORT_SYMBOL(blk_queue_softirq_done);
+
/**
* blk_queue_make_request - define an alternate make_request function for a device
* @q: the request queue for the device to be affected
static inline void rq_init(request_queue_t *q, struct request *rq)
{
INIT_LIST_HEAD(&rq->queuelist);
+ INIT_LIST_HEAD(&rq->donelist);
rq->errors = 0;
rq->rq_status = RQ_ACTIVE;
rq->sense = NULL;
rq->end_io = NULL;
rq->end_io_data = NULL;
+ rq->completion_data = NULL;
}
/**
* blk_queue_ordered - does this queue support ordered writes
* @q: the request queue
* @ordered: one of QUEUE_ORDERED_*
+ * @prepare_flush_fn: rq setup helper for cache flush ordered writes
*
* Description:
* For journalled file systems, doing ordered writes on a commit
return -EINVAL;
}
+ q->ordered = ordered;
q->next_ordered = ordered;
q->prepare_flush_fn = prepare_flush_fn;
rq->end_io = end_io;
q->prepare_flush_fn(q, rq);
- __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
+ elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
}
static inline struct request *start_ordered(request_queue_t *q,
else
q->ordseq |= QUEUE_ORDSEQ_POSTFLUSH;
- __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
+ elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
if (q->ordered & QUEUE_ORDERED_PREFLUSH) {
queue_flush(q, QUEUE_ORDERED_PREFLUSH);
int blk_do_ordered(request_queue_t *q, struct request **rqp)
{
- struct request *rq = *rqp, *allowed_rq;
+ struct request *rq = *rqp;
int is_barrier = blk_fs_request(rq) && blk_barrier_rq(rq);
if (!q->ordseq) {
}
}
+ /*
+ * Ordered sequence in progress
+ */
+
+ /* Special requests are not subject to ordering rules. */
+ if (!blk_fs_request(rq) &&
+ rq != &q->pre_flush_rq && rq != &q->post_flush_rq)
+ return 1;
+
if (q->ordered & QUEUE_ORDERED_TAG) {
+ /* Ordered by tag. Blocking the next barrier is enough. */
if (is_barrier && rq != &q->bar_rq)
*rqp = NULL;
- return 1;
- }
-
- switch (blk_ordered_cur_seq(q)) {
- case QUEUE_ORDSEQ_PREFLUSH:
- allowed_rq = &q->pre_flush_rq;
- break;
- case QUEUE_ORDSEQ_BAR:
- allowed_rq = &q->bar_rq;
- break;
- case QUEUE_ORDSEQ_POSTFLUSH:
- allowed_rq = &q->post_flush_rq;
- break;
- default:
- allowed_rq = NULL;
- break;
+ } else {
+ /* Ordered by draining. Wait for turn. */
+ WARN_ON(blk_ordered_req_seq(rq) < blk_ordered_cur_seq(q));
+ if (blk_ordered_req_seq(rq) > blk_ordered_cur_seq(q))
+ *rqp = NULL;
}
- if (rq != allowed_rq &&
- (blk_fs_request(rq) || rq == &q->pre_flush_rq ||
- rq == &q->post_flush_rq))
- *rqp = NULL;
-
return 1;
}
* Different hardware can have different requirements as to what pages
* it can do I/O directly to. A low level driver can call
* blk_queue_bounce_limit to have lower memory pages allocated as bounce
- * buffers for doing I/O to pages residing above @page. By default
- * the block layer sets this to the highest numbered "low" memory page.
+ * buffers for doing I/O to pages residing above @page.
**/
void blk_queue_bounce_limit(request_queue_t *q, u64 dma_addr)
{
unsigned long bounce_pfn = dma_addr >> PAGE_SHIFT;
-
- /*
- * set appropriate bounce gfp mask -- unfortunately we don't have a
- * full 4GB zone, so we have to resort to low memory for any bounces.
- * ISA has its own < 16MB zone.
- */
- if (bounce_pfn < blk_max_low_pfn) {
- BUG_ON(dma_addr < BLK_BOUNCE_ISA);
+ int dma = 0;
+
+ q->bounce_gfp = GFP_NOIO;
+#if BITS_PER_LONG == 64
+ /* Assume anything <= 4GB can be handled by IOMMU.
+ Actually some IOMMUs can handle everything, but I don't
+ know of a way to test this here. */
+ if (bounce_pfn < (0xffffffff>>PAGE_SHIFT))
+ dma = 1;
+ q->bounce_pfn = max_low_pfn;
+#else
+ if (bounce_pfn < blk_max_low_pfn)
+ dma = 1;
+ q->bounce_pfn = bounce_pfn;
+#endif
+ if (dma) {
init_emergency_isa_pool();
q->bounce_gfp = GFP_NOIO | GFP_DMA;
- } else
- q->bounce_gfp = GFP_NOIO;
-
- q->bounce_pfn = bounce_pfn;
+ q->bounce_pfn = bounce_pfn;
+ }
}
EXPORT_SYMBOL(blk_queue_bounce_limit);
* Enables a low level driver to set an upper limit on the size of
* received requests.
**/
-void blk_queue_max_sectors(request_queue_t *q, unsigned short max_sectors)
+void blk_queue_max_sectors(request_queue_t *q, unsigned int max_sectors)
{
if ((max_sectors << 9) < PAGE_CACHE_SIZE) {
max_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
t->max_hw_segments = min(t->max_hw_segments,b->max_hw_segments);
t->max_segment_size = min(t->max_segment_size,b->max_segment_size);
t->hardsect_size = max(t->hardsect_size,b->hardsect_size);
+ if (!test_bit(QUEUE_FLAG_CLUSTER, &b->queue_flags))
+ clear_bit(QUEUE_FLAG_CLUSTER, &t->queue_flags);
}
EXPORT_SYMBOL(blk_queue_stack_limits);
__FUNCTION__, depth);
}
- tag_index = kmalloc(depth * sizeof(struct request *), GFP_ATOMIC);
+ tag_index = kzalloc(depth * sizeof(struct request *), GFP_ATOMIC);
if (!tag_index)
goto fail;
nr_ulongs = ALIGN(depth, BITS_PER_LONG) / BITS_PER_LONG;
- tag_map = kmalloc(nr_ulongs * sizeof(unsigned long), GFP_ATOMIC);
+ tag_map = kzalloc(nr_ulongs * sizeof(unsigned long), GFP_ATOMIC);
if (!tag_map)
goto fail;
- memset(tag_index, 0, depth * sizeof(struct request *));
- memset(tag_map, 0, nr_ulongs * sizeof(unsigned long));
tags->real_max_depth = depth;
tags->max_depth = depth;
tags->tag_index = tag_index;
if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))
return;
- if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags))
+ if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) {
mod_timer(&q->unplug_timer, jiffies + q->unplug_delay);
+ blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG);
+ }
}
EXPORT_SYMBOL(blk_plug_device);
/*
* devices don't necessarily have an ->unplug_fn defined
*/
- if (q->unplug_fn)
+ if (q->unplug_fn) {
+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
+ q->rq.count[READ] + q->rq.count[WRITE]);
+
q->unplug_fn(q);
+ }
}
static void blk_unplug_work(void *data)
{
request_queue_t *q = data;
+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
+ q->rq.count[READ] + q->rq.count[WRITE]);
+
q->unplug_fn(q);
}
{
request_queue_t *q = (request_queue_t *)data;
+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_TIMER, NULL,
+ q->rq.count[READ] + q->rq.count[WRITE]);
+
kblockd_schedule_work(&q->unplug_work);
}
/**
* blk_cleanup_queue: - release a &request_queue_t when it is no longer needed
- * @q: the request queue to be released
+ * @kobj: the kobj belonging of the request queue to be released
*
* Description:
* blk_cleanup_queue is the pair to blk_init_queue() or
* Hopefully the low level driver will have finished any
* outstanding requests first...
**/
-void blk_cleanup_queue(request_queue_t * q)
+static void blk_release_queue(struct kobject *kobj)
{
+ request_queue_t *q = container_of(kobj, struct request_queue, kobj);
struct request_list *rl = &q->rq;
- if (!atomic_dec_and_test(&q->refcnt))
- return;
-
- if (q->elevator)
- elevator_exit(q->elevator);
-
blk_sync_queue(q);
if (rl->rq_pool)
if (q->queue_tags)
__blk_queue_free_tags(q);
+ if (q->blk_trace)
+ blk_trace_shutdown(q);
+
kmem_cache_free(requestq_cachep, q);
}
+void blk_put_queue(request_queue_t *q)
+{
+ kobject_put(&q->kobj);
+}
+EXPORT_SYMBOL(blk_put_queue);
+
+void blk_cleanup_queue(request_queue_t * q)
+{
+ mutex_lock(&q->sysfs_lock);
+ set_bit(QUEUE_FLAG_DEAD, &q->queue_flags);
+ mutex_unlock(&q->sysfs_lock);
+
+ if (q->elevator)
+ elevator_exit(q->elevator);
+
+ blk_put_queue(q);
+}
+
EXPORT_SYMBOL(blk_cleanup_queue);
static int blk_init_free_list(request_queue_t *q)
}
EXPORT_SYMBOL(blk_alloc_queue);
+static struct kobj_type queue_ktype;
+
request_queue_t *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
{
request_queue_t *q;
memset(q, 0, sizeof(*q));
init_timer(&q->unplug_timer);
- atomic_set(&q->refcnt, 1);
+
+ snprintf(q->kobj.name, KOBJ_NAME_LEN, "%s", "queue");
+ q->kobj.ktype = &queue_ktype;
+ kobject_init(&q->kobj);
q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
q->backing_dev_info.unplug_io_data = q;
+ mutex_init(&q->sysfs_lock);
+
return q;
}
EXPORT_SYMBOL(blk_alloc_queue_node);
return NULL;
q->node = node_id;
- if (blk_init_free_list(q))
- goto out_init;
+ if (blk_init_free_list(q)) {
+ kmem_cache_free(requestq_cachep, q);
+ return NULL;
+ }
/*
* if caller didn't supply a lock, they get per-queue locking with
return q;
}
- blk_cleanup_queue(q);
-out_init:
- kmem_cache_free(requestq_cachep, q);
+ blk_put_queue(q);
return NULL;
}
EXPORT_SYMBOL(blk_init_queue_node);
int blk_get_queue(request_queue_t *q)
{
if (likely(!test_bit(QUEUE_FLAG_DEAD, &q->queue_flags))) {
- atomic_inc(&q->refcnt);
+ kobject_get(&q->kobj);
return 0;
}
rq_init(q, rq);
rq->rl = rl;
+
+ blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ);
out:
return rq;
}
if (!rq) {
struct io_context *ioc;
+ blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ);
+
__generic_unplug_device(q);
spin_unlock_irq(q->queue_lock);
io_schedule();
*/
void blk_requeue_request(request_queue_t *q, struct request *rq)
{
+ blk_add_trace_rq(q, rq, BLK_TA_REQUEUE);
+
if (blk_rq_tagged(rq))
blk_queue_end_tag(q, rq);
rq->rq_disk = bd_disk;
rq->flags |= REQ_NOMERGE;
rq->end_io = done;
- elv_add_request(q, rq, where, 1);
- generic_unplug_device(q);
+ WARN_ON(irqs_disabled());
+ spin_lock_irq(q->queue_lock);
+ __elv_add_request(q, rq, where, 1);
+ __generic_unplug_device(q);
+ spin_unlock_irq(q->queue_lock);
}
-
EXPORT_SYMBOL_GPL(blk_execute_rq_nowait);
/**
disk->stamp = now;
}
+EXPORT_SYMBOL_GPL(disk_round_stats);
+
/*
* queue lock must be held
*/
/**
* blk_end_sync_rq - executes a completion event on a request
* @rq: request to complete
+ * @error: end io status of the request
*/
void blk_end_sync_rq(struct request *rq, int error)
{
if (!q->back_merge_fn(q, req, bio))
break;
+ blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
+
req->biotail->bi_next = bio;
req->biotail = bio;
req->nr_sectors = req->hard_nr_sectors += nr_sectors;
if (!q->front_merge_fn(q, req, bio))
break;
+ blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
+
bio->bi_next = req->bio;
req->bio = bio;
request_queue_t *q;
sector_t maxsector;
int ret, nr_sectors = bio_sectors(bio);
+ dev_t old_dev;
might_sleep();
/* Test device or partition size, when known. */
* NOTE: we don't repeat the blk_size check for each new device.
* Stacking drivers are expected to know what they are doing.
*/
+ maxsector = -1;
+ old_dev = 0;
do {
char b[BDEVNAME_SIZE];
*/
blk_partition_remap(bio);
+ if (maxsector != -1)
+ blk_add_trace_remap(q, bio, old_dev, bio->bi_sector,
+ maxsector);
+
+ blk_add_trace_bio(q, bio, BLK_TA_QUEUE);
+
+ maxsector = bio->bi_sector;
+ old_dev = bio->bi_bdev->bd_dev;
+
ret = q->make_request_fn(q, bio);
} while (ret);
}
int total_bytes, bio_nbytes, error, next_idx = 0;
struct bio *bio;
+ blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE);
+
/*
* extend uptodate bool to allow < 0 value to be direct io error
*/
if (blk_fs_request(req) && req->rq_disk) {
const int rw = rq_data_dir(req);
- __disk_stat_add(req->rq_disk, sectors[rw], nr_bytes >> 9);
+ disk_stat_add(req->rq_disk, sectors[rw], nr_bytes >> 9);
}
total_bytes = bio_nbytes = 0;
EXPORT_SYMBOL(end_that_request_chunk);
/*
+ * splice the completion data to a local structure and hand off to
+ * process_completion_queue() to complete the requests
+ */
+static void blk_done_softirq(struct softirq_action *h)
+{
+ struct list_head *cpu_list;
+ LIST_HEAD(local_list);
+
+ local_irq_disable();
+ cpu_list = &__get_cpu_var(blk_cpu_done);
+ list_splice_init(cpu_list, &local_list);
+ local_irq_enable();
+
+ while (!list_empty(&local_list)) {
+ struct request *rq = list_entry(local_list.next, struct request, donelist);
+
+ list_del_init(&rq->donelist);
+ rq->q->softirq_done_fn(rq);
+ }
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
+ void *hcpu)
+{
+ /*
+ * If a CPU goes away, splice its entries to the current CPU
+ * and trigger a run of the softirq
+ */
+ if (action == CPU_DEAD) {
+ int cpu = (unsigned long) hcpu;
+
+ local_irq_disable();
+ list_splice_init(&per_cpu(blk_cpu_done, cpu),
+ &__get_cpu_var(blk_cpu_done));
+ raise_softirq_irqoff(BLOCK_SOFTIRQ);
+ local_irq_enable();
+ }
+
+ return NOTIFY_OK;
+}
+
+
+static struct notifier_block __devinitdata blk_cpu_notifier = {
+ .notifier_call = blk_cpu_notify,
+};
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
+/**
+ * blk_complete_request - end I/O on a request
+ * @req: the request being processed
+ *
+ * Description:
+ * Ends all I/O on a request. It does not handle partial completions,
+ * unless the driver actually implements this in its completionc callback
+ * through requeueing. Theh actual completion happens out-of-order,
+ * through a softirq handler. The user must have registered a completion
+ * callback through blk_queue_softirq_done().
+ **/
+
+void blk_complete_request(struct request *req)
+{
+ struct list_head *cpu_list;
+ unsigned long flags;
+
+ BUG_ON(!req->q->softirq_done_fn);
+
+ local_irq_save(flags);
+
+ cpu_list = &__get_cpu_var(blk_cpu_done);
+ list_add_tail(&req->donelist, cpu_list);
+ raise_softirq_irqoff(BLOCK_SOFTIRQ);
+
+ local_irq_restore(flags);
+}
+
+EXPORT_SYMBOL(blk_complete_request);
+
+/*
* queue lock must be held
*/
void end_that_request_last(struct request *req, int uptodate)
int __init blk_dev_init(void)
{
+ int i;
+
kblockd_workqueue = create_workqueue("kblockd");
if (!kblockd_workqueue)
panic("Failed to create kblockd\n");
iocontext_cachep = kmem_cache_create("blkdev_ioc",
sizeof(struct io_context), 0, SLAB_PANIC, NULL, NULL);
+ for_each_possible_cpu(i)
+ INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));
+
+ open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL);
+#ifdef CONFIG_HOTPLUG_CPU
+ register_cpu_notifier(&blk_cpu_notifier);
+#endif
+
blk_max_low_pfn = max_low_pfn;
blk_max_pfn = max_pfn;
BUG_ON(atomic_read(&ioc->refcount) == 0);
if (atomic_dec_and_test(&ioc->refcount)) {
+ struct cfq_io_context *cic;
+
+ rcu_read_lock();
if (ioc->aic && ioc->aic->dtor)
ioc->aic->dtor(ioc->aic);
- if (ioc->cic && ioc->cic->dtor)
- ioc->cic->dtor(ioc->cic);
+ if (ioc->cic_root.rb_node != NULL) {
+ struct rb_node *n = rb_first(&ioc->cic_root);
+
+ cic = rb_entry(n, struct cfq_io_context, rb_node);
+ cic->dtor(ioc);
+ }
+ rcu_read_unlock();
kmem_cache_free(iocontext_cachep, ioc);
}
{
unsigned long flags;
struct io_context *ioc;
+ struct cfq_io_context *cic;
local_irq_save(flags);
task_lock(current);
if (ioc->aic && ioc->aic->exit)
ioc->aic->exit(ioc->aic);
- if (ioc->cic && ioc->cic->exit)
- ioc->cic->exit(ioc->cic);
-
+ if (ioc->cic_root.rb_node != NULL) {
+ cic = rb_entry(rb_first(&ioc->cic_root), struct cfq_io_context, rb_node);
+ cic->exit(ioc);
+ }
+
put_io_context(ioc);
}
ret->last_waited = jiffies; /* doesn't matter... */
ret->nr_batch_requests = 0; /* because this is 0 */
ret->aic = NULL;
- ret->cic = NULL;
+ ret->cic_root.rb_node = NULL;
tsk->io_context = ret;
}
queue_requests_store(struct request_queue *q, const char *page, size_t count)
{
struct request_list *rl = &q->rq;
+ unsigned long nr;
+ int ret = queue_var_store(&nr, page, count);
+ if (nr < BLKDEV_MIN_RQ)
+ nr = BLKDEV_MIN_RQ;
- int ret = queue_var_store(&q->nr_requests, page, count);
- if (q->nr_requests < BLKDEV_MIN_RQ)
- q->nr_requests = BLKDEV_MIN_RQ;
+ spin_lock_irq(q->queue_lock);
+ q->nr_requests = nr;
blk_queue_congestion_threshold(q);
if (rl->count[READ] >= queue_congestion_on_threshold(q))
blk_clear_queue_full(q, WRITE);
wake_up(&rl->wait[WRITE]);
}
+ spin_unlock_irq(q->queue_lock);
return ret;
}
queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
{
struct queue_sysfs_entry *entry = to_queue(attr);
- struct request_queue *q;
+ request_queue_t *q = container_of(kobj, struct request_queue, kobj);
+ ssize_t res;
- q = container_of(kobj, struct request_queue, kobj);
if (!entry->show)
return -EIO;
-
- return entry->show(q, page);
+ mutex_lock(&q->sysfs_lock);
+ if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
+ mutex_unlock(&q->sysfs_lock);
+ return -ENOENT;
+ }
+ res = entry->show(q, page);
+ mutex_unlock(&q->sysfs_lock);
+ return res;
}
static ssize_t
const char *page, size_t length)
{
struct queue_sysfs_entry *entry = to_queue(attr);
- struct request_queue *q;
+ request_queue_t *q = container_of(kobj, struct request_queue, kobj);
+
+ ssize_t res;
- q = container_of(kobj, struct request_queue, kobj);
if (!entry->store)
return -EIO;
-
- return entry->store(q, page, length);
+ mutex_lock(&q->sysfs_lock);
+ if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
+ mutex_unlock(&q->sysfs_lock);
+ return -ENOENT;
+ }
+ res = entry->store(q, page, length);
+ mutex_unlock(&q->sysfs_lock);
+ return res;
}
static struct sysfs_ops queue_sysfs_ops = {
static struct kobj_type queue_ktype = {
.sysfs_ops = &queue_sysfs_ops,
.default_attrs = default_attrs,
+ .release = blk_release_queue,
};
int blk_register_queue(struct gendisk *disk)
return -ENXIO;
q->kobj.parent = kobject_get(&disk->kobj);
- if (!q->kobj.parent)
- return -EBUSY;
- snprintf(q->kobj.name, KOBJ_NAME_LEN, "%s", "queue");
- q->kobj.ktype = &queue_ktype;
-
- ret = kobject_register(&q->kobj);
+ ret = kobject_add(&q->kobj);
if (ret < 0)
return ret;
+ kobject_uevent(&q->kobj, KOBJ_ADD);
+
ret = elv_register_queue(q);
if (ret) {
- kobject_unregister(&q->kobj);
+ kobject_uevent(&q->kobj, KOBJ_REMOVE);
+ kobject_del(&q->kobj);
return ret;
}
if (q && q->request_fn) {
elv_unregister_queue(q);
- kobject_unregister(&q->kobj);
+ kobject_uevent(&q->kobj, KOBJ_REMOVE);
+ kobject_del(&q->kobj);
kobject_put(&disk->kobj);
}
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff