#include <linux/swap.h>
#include <linux/writeback.h>
#include <linux/task_io_accounting_ops.h>
-#include <linux/blktrace_api.h>
#include <linux/fault-inject.h>
-#include <trace/block.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/block.h>
#include "blk.h"
-DEFINE_TRACE(block_plug);
-DEFINE_TRACE(block_unplug_io);
-DEFINE_TRACE(block_unplug_timer);
-DEFINE_TRACE(block_getrq);
-DEFINE_TRACE(block_sleeprq);
-DEFINE_TRACE(block_rq_requeue);
-DEFINE_TRACE(block_bio_backmerge);
-DEFINE_TRACE(block_bio_frontmerge);
-DEFINE_TRACE(block_bio_queue);
-DEFINE_TRACE(block_rq_complete);
-DEFINE_TRACE(block_remap); /* Also used in drivers/md/dm.c */
EXPORT_TRACEPOINT_SYMBOL_GPL(block_remap);
+EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);
+EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);
static int __make_request(struct request_queue *q, struct bio *bio);
return;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(rq->rq_disk, rq->sector);
+ part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
if (!new_io)
part_stat_inc(cpu, part, merges[rw]);
else {
part_round_stats(cpu, part);
- part_inc_in_flight(part);
+ part_inc_in_flight(part, rw);
}
part_stat_unlock();
INIT_LIST_HEAD(&rq->timeout_list);
rq->cpu = -1;
rq->q = q;
- rq->sector = rq->hard_sector = (sector_t) -1;
+ rq->__sector = (sector_t) -1;
INIT_HLIST_NODE(&rq->hash);
RB_CLEAR_NODE(&rq->rb_node);
rq->cmd = rq->__cmd;
rq->rq_disk ? rq->rq_disk->disk_name : "?", rq->cmd_type,
rq->cmd_flags);
- printk(KERN_INFO " sector %llu, nr/cnr %lu/%u\n",
- (unsigned long long)rq->sector,
- rq->nr_sectors,
- rq->current_nr_sectors);
+ printk(KERN_INFO " sector %llu, nr/cnr %u/%u\n",
+ (unsigned long long)blk_rq_pos(rq),
+ blk_rq_sectors(rq), blk_rq_cur_sectors(rq));
printk(KERN_INFO " bio %p, biotail %p, buffer %p, len %u\n",
- rq->bio, rq->biotail,
- rq->buffer, rq->data_len);
+ rq->bio, rq->biotail, rq->buffer, blk_rq_bytes(rq));
if (blk_pc_request(rq)) {
printk(KERN_INFO " cdb: ");
q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
q->backing_dev_info.unplug_io_data = q;
+ q->backing_dev_info.ra_pages =
+ (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
+ q->backing_dev_info.state = 0;
+ q->backing_dev_info.capabilities = BDI_CAP_MAP_COPY;
+ q->backing_dev_info.name = "block";
+
err = bdi_init(&q->backing_dev_info);
if (err) {
kmem_cache_free(blk_requestq_cachep, q);
return NULL;
}
- /*
- * if caller didn't supply a lock, they get per-queue locking with
- * our embedded lock
- */
- if (!lock)
- lock = &q->__queue_lock;
-
q->request_fn = rfn;
q->prep_rq_fn = NULL;
q->unplug_fn = generic_unplug_device;
q->sg_reserved_size = INT_MAX;
- blk_set_cmd_filter_defaults(&q->cmd_filter);
-
/*
* all done
*/
EXPORT_SYMBOL(blk_get_request);
/**
+ * blk_make_request - given a bio, allocate a corresponding struct request.
+ * @q: target request queue
+ * @bio: The bio describing the memory mappings that will be submitted for IO.
+ * It may be a chained-bio properly constructed by block/bio layer.
+ * @gfp_mask: gfp flags to be used for memory allocation
+ *
+ * blk_make_request is the parallel of generic_make_request for BLOCK_PC
+ * type commands. Where the struct request needs to be farther initialized by
+ * the caller. It is passed a &struct bio, which describes the memory info of
+ * the I/O transfer.
+ *
+ * The caller of blk_make_request must make sure that bi_io_vec
+ * are set to describe the memory buffers. That bio_data_dir() will return
+ * the needed direction of the request. (And all bio's in the passed bio-chain
+ * are properly set accordingly)
+ *
+ * If called under none-sleepable conditions, mapped bio buffers must not
+ * need bouncing, by calling the appropriate masked or flagged allocator,
+ * suitable for the target device. Otherwise the call to blk_queue_bounce will
+ * BUG.
+ *
+ * WARNING: When allocating/cloning a bio-chain, careful consideration should be
+ * given to how you allocate bios. In particular, you cannot use __GFP_WAIT for
+ * anything but the first bio in the chain. Otherwise you risk waiting for IO
+ * completion of a bio that hasn't been submitted yet, thus resulting in a
+ * deadlock. Alternatively bios should be allocated using bio_kmalloc() instead
+ * of bio_alloc(), as that avoids the mempool deadlock.
+ * If possible a big IO should be split into smaller parts when allocation
+ * fails. Partial allocation should not be an error, or you risk a live-lock.
+ */
+struct request *blk_make_request(struct request_queue *q, struct bio *bio,
+ gfp_t gfp_mask)
+{
+ struct request *rq = blk_get_request(q, bio_data_dir(bio), gfp_mask);
+
+ if (unlikely(!rq))
+ return ERR_PTR(-ENOMEM);
+
+ for_each_bio(bio) {
+ struct bio *bounce_bio = bio;
+ int ret;
+
+ blk_queue_bounce(q, &bounce_bio);
+ ret = blk_rq_append_bio(q, rq, bounce_bio);
+ if (unlikely(ret)) {
+ blk_put_request(rq);
+ return ERR_PTR(ret);
+ }
+ }
+
+ return rq;
+}
+EXPORT_SYMBOL(blk_make_request);
+
+/**
* blk_requeue_request - put a request back on queue
* @q: request queue where request should be inserted
* @rq: request to be inserted
if (blk_rq_tagged(rq))
blk_queue_end_tag(q, rq);
+ BUG_ON(blk_queued_rq(rq));
+
elv_requeue_request(q, rq);
}
EXPORT_SYMBOL(blk_requeue_request);
if (now == part->stamp)
return;
- if (part->in_flight) {
+ if (part_in_flight(part)) {
__part_stat_add(cpu, part, time_in_queue,
- part->in_flight * (now - part->stamp));
+ part_in_flight(part) * (now - part->stamp));
__part_stat_add(cpu, part, io_ticks, (now - part->stamp));
}
part->stamp = now;
req->cmd_type = REQ_TYPE_FS;
/*
- * inherit FAILFAST from bio (for read-ahead, and explicit FAILFAST)
+ * Inherit FAILFAST from bio (for read-ahead, and explicit
+ * FAILFAST). FAILFAST flags are identical for req and bio.
*/
- if (bio_rw_ahead(bio))
- req->cmd_flags |= (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
- REQ_FAILFAST_DRIVER);
- if (bio_failfast_dev(bio))
- req->cmd_flags |= REQ_FAILFAST_DEV;
- if (bio_failfast_transport(bio))
- req->cmd_flags |= REQ_FAILFAST_TRANSPORT;
- if (bio_failfast_driver(bio))
- req->cmd_flags |= REQ_FAILFAST_DRIVER;
-
- if (unlikely(bio_discard(bio))) {
+ if (bio_rw_flagged(bio, BIO_RW_AHEAD))
+ req->cmd_flags |= REQ_FAILFAST_MASK;
+ else
+ req->cmd_flags |= bio->bi_rw & REQ_FAILFAST_MASK;
+
+ if (unlikely(bio_rw_flagged(bio, BIO_RW_DISCARD))) {
req->cmd_flags |= REQ_DISCARD;
- if (bio_barrier(bio))
+ if (bio_rw_flagged(bio, BIO_RW_BARRIER))
req->cmd_flags |= REQ_SOFTBARRIER;
- req->q->prepare_discard_fn(req->q, req);
- } else if (unlikely(bio_barrier(bio)))
+ } else if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER)))
req->cmd_flags |= REQ_HARDBARRIER;
- if (bio_sync(bio))
+ if (bio_rw_flagged(bio, BIO_RW_SYNCIO))
req->cmd_flags |= REQ_RW_SYNC;
- if (bio_rw_meta(bio))
+ if (bio_rw_flagged(bio, BIO_RW_META))
req->cmd_flags |= REQ_RW_META;
- if (bio_noidle(bio))
+ if (bio_rw_flagged(bio, BIO_RW_NOIDLE))
req->cmd_flags |= REQ_NOIDLE;
req->errors = 0;
- req->hard_sector = req->sector = bio->bi_sector;
+ req->__sector = bio->bi_sector;
req->ioprio = bio_prio(bio);
blk_rq_bio_prep(req->q, req, bio);
}
*/
static inline bool queue_should_plug(struct request_queue *q)
{
- return !(blk_queue_nonrot(q) && blk_queue_tagged(q));
+ return !(blk_queue_nonrot(q) && blk_queue_queuing(q));
}
static int __make_request(struct request_queue *q, struct bio *bio)
{
struct request *req;
- int el_ret, nr_sectors;
+ int el_ret;
+ unsigned int bytes = bio->bi_size;
const unsigned short prio = bio_prio(bio);
- const int sync = bio_sync(bio);
- const int unplug = bio_unplug(bio);
+ const bool sync = bio_rw_flagged(bio, BIO_RW_SYNCIO);
+ const bool unplug = bio_rw_flagged(bio, BIO_RW_UNPLUG);
+ const unsigned int ff = bio->bi_rw & REQ_FAILFAST_MASK;
int rw_flags;
- nr_sectors = bio_sectors(bio);
-
+ if (bio_rw_flagged(bio, BIO_RW_BARRIER) && bio_has_data(bio) &&
+ (q->next_ordered == QUEUE_ORDERED_NONE)) {
+ bio_endio(bio, -EOPNOTSUPP);
+ return 0;
+ }
/*
* low level driver can indicate that it wants pages above a
* certain limit bounced to low memory (ie for highmem, or even
spin_lock_irq(q->queue_lock);
- if (unlikely(bio_barrier(bio)) || elv_queue_empty(q))
+ if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER)) || elv_queue_empty(q))
goto get_rq;
el_ret = elv_merge(q, &req, bio);
trace_block_bio_backmerge(q, bio);
+ if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
+ blk_rq_set_mixed_merge(req);
+
req->biotail->bi_next = bio;
req->biotail = bio;
- req->nr_sectors = req->hard_nr_sectors += nr_sectors;
+ req->__data_len += bytes;
req->ioprio = ioprio_best(req->ioprio, prio);
if (!blk_rq_cpu_valid(req))
req->cpu = bio->bi_comp_cpu;
trace_block_bio_frontmerge(q, bio);
+ if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) {
+ blk_rq_set_mixed_merge(req);
+ req->cmd_flags &= ~REQ_FAILFAST_MASK;
+ req->cmd_flags |= ff;
+ }
+
bio->bi_next = req->bio;
req->bio = bio;
* not touch req->buffer either...
*/
req->buffer = bio_data(bio);
- req->current_nr_sectors = bio_cur_sectors(bio);
- req->hard_cur_sectors = req->current_nr_sectors;
- req->sector = req->hard_sector = bio->bi_sector;
- req->nr_sectors = req->hard_nr_sectors += nr_sectors;
+ req->__sector = bio->bi_sector;
+ req->__data_len += bytes;
req->ioprio = ioprio_best(req->ioprio, prio);
if (!blk_rq_cpu_valid(req))
req->cpu = bio->bi_comp_cpu;
bio->bi_bdev = bdev->bd_contains;
trace_block_remap(bdev_get_queue(bio->bi_bdev), bio,
- bdev->bd_dev, bio->bi_sector,
+ bdev->bd_dev,
bio->bi_sector - p->start_sect);
}
}
goto end_io;
}
- if (unlikely(nr_sectors > q->max_hw_sectors)) {
+ if (unlikely(!bio_rw_flagged(bio, BIO_RW_DISCARD) &&
+ nr_sectors > queue_max_hw_sectors(q))) {
printk(KERN_ERR "bio too big device %s (%u > %u)\n",
- bdevname(bio->bi_bdev, b),
- bio_sectors(bio),
- q->max_hw_sectors);
+ bdevname(bio->bi_bdev, b),
+ bio_sectors(bio),
+ queue_max_hw_sectors(q));
goto end_io;
}
goto end_io;
if (old_sector != -1)
- trace_block_remap(q, bio, old_dev, bio->bi_sector,
- old_sector);
-
- trace_block_bio_queue(q, bio);
+ trace_block_remap(q, bio, old_dev, old_sector);
old_sector = bio->bi_sector;
old_dev = bio->bi_bdev->bd_dev;
if (bio_check_eod(bio, nr_sectors))
goto end_io;
- if (bio_discard(bio) && !q->prepare_discard_fn) {
- err = -EOPNOTSUPP;
- goto end_io;
- }
- if (bio_barrier(bio) && bio_has_data(bio) &&
- (q->next_ordered == QUEUE_ORDERED_NONE)) {
+ if (bio_rw_flagged(bio, BIO_RW_DISCARD) &&
+ !blk_queue_discard(q)) {
err = -EOPNOTSUPP;
goto end_io;
}
+ trace_block_bio_queue(q, bio);
+
ret = q->make_request_fn(q, bio);
} while (ret);
*/
int blk_rq_check_limits(struct request_queue *q, struct request *rq)
{
- if (rq->nr_sectors > q->max_sectors ||
- rq->data_len > q->max_hw_sectors << 9) {
+ if (blk_rq_sectors(rq) > queue_max_sectors(q) ||
+ blk_rq_bytes(rq) > queue_max_hw_sectors(q) << 9) {
printk(KERN_ERR "%s: over max size limit.\n", __func__);
return -EIO;
}
* limitation.
*/
blk_recalc_rq_segments(rq);
- if (rq->nr_phys_segments > q->max_phys_segments ||
- rq->nr_phys_segments > q->max_hw_segments) {
+ if (rq->nr_phys_segments > queue_max_phys_segments(q) ||
+ rq->nr_phys_segments > queue_max_hw_segments(q)) {
printk(KERN_ERR "%s: over max segments limit.\n", __func__);
return -EIO;
}
EXPORT_SYMBOL_GPL(blk_insert_cloned_request);
/**
- * blkdev_dequeue_request - dequeue request and start timeout timer
- * @req: request to dequeue
+ * blk_rq_err_bytes - determine number of bytes till the next failure boundary
+ * @rq: request to examine
*
- * Dequeue @req and start timeout timer on it. This hands off the
- * request to the driver.
+ * Description:
+ * A request could be merge of IOs which require different failure
+ * handling. This function determines the number of bytes which
+ * can be failed from the beginning of the request without
+ * crossing into area which need to be retried further.
*
- * Block internal functions which don't want to start timer should
- * call elv_dequeue_request().
+ * Return:
+ * The number of bytes to fail.
+ *
+ * Context:
+ * queue_lock must be held.
*/
-void blkdev_dequeue_request(struct request *req)
+unsigned int blk_rq_err_bytes(const struct request *rq)
{
- elv_dequeue_request(req->q, req);
+ unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK;
+ unsigned int bytes = 0;
+ struct bio *bio;
+
+ if (!(rq->cmd_flags & REQ_MIXED_MERGE))
+ return blk_rq_bytes(rq);
/*
- * We are now handing the request to the hardware, add the
- * timeout handler.
+ * Currently the only 'mixing' which can happen is between
+ * different fastfail types. We can safely fail portions
+ * which have all the failfast bits that the first one has -
+ * the ones which are at least as eager to fail as the first
+ * one.
*/
- blk_add_timer(req);
+ for (bio = rq->bio; bio; bio = bio->bi_next) {
+ if ((bio->bi_rw & ff) != ff)
+ break;
+ bytes += bio->bi_size;
+ }
+
+ /* this could lead to infinite loop */
+ BUG_ON(blk_rq_bytes(rq) && !bytes);
+ return bytes;
}
-EXPORT_SYMBOL(blkdev_dequeue_request);
+EXPORT_SYMBOL_GPL(blk_rq_err_bytes);
static void blk_account_io_completion(struct request *req, unsigned int bytes)
{
int cpu;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(req->rq_disk, req->sector);
+ part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
part_stat_add(cpu, part, sectors[rw], bytes >> 9);
part_stat_unlock();
}
int cpu;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(req->rq_disk, req->sector);
+ part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
part_stat_inc(cpu, part, ios[rw]);
part_stat_add(cpu, part, ticks[rw], duration);
part_round_stats(cpu, part);
- part_dec_in_flight(part);
+ part_dec_in_flight(part, rw);
part_stat_unlock();
}
}
/**
- * blk_rq_bytes - Returns bytes left to complete in the entire request
- * @rq: the request being processed
- **/
-unsigned int blk_rq_bytes(struct request *rq)
-{
- if (blk_fs_request(rq))
- return rq->hard_nr_sectors << 9;
-
- return rq->data_len;
-}
-EXPORT_SYMBOL_GPL(blk_rq_bytes);
-
-/**
- * blk_rq_cur_bytes - Returns bytes left to complete in the current segment
- * @rq: the request being processed
- **/
-unsigned int blk_rq_cur_bytes(struct request *rq)
-{
- if (blk_fs_request(rq))
- return rq->current_nr_sectors << 9;
-
- if (rq->bio)
- return rq->bio->bi_size;
-
- return rq->data_len;
-}
-EXPORT_SYMBOL_GPL(blk_rq_cur_bytes);
-
-struct request *elv_next_request(struct request_queue *q)
+ * blk_peek_request - peek at the top of a request queue
+ * @q: request queue to peek at
+ *
+ * Description:
+ * Return the request at the top of @q. The returned request
+ * should be started using blk_start_request() before LLD starts
+ * processing it.
+ *
+ * Return:
+ * Pointer to the request at the top of @q if available. Null
+ * otherwise.
+ *
+ * Context:
+ * queue_lock must be held.
+ */
+struct request *blk_peek_request(struct request_queue *q)
{
struct request *rq;
int ret;
if (rq->cmd_flags & REQ_DONTPREP)
break;
- if (q->dma_drain_size && rq->data_len) {
+ if (q->dma_drain_size && blk_rq_bytes(rq)) {
/*
* make sure space for the drain appears we
* know we can do this because max_hw_segments
* avoid resource deadlock. REQ_STARTED will
* prevent other fs requests from passing this one.
*/
- if (q->dma_drain_size && rq->data_len &&
+ if (q->dma_drain_size && blk_rq_bytes(rq) &&
!(rq->cmd_flags & REQ_DONTPREP)) {
/*
* remove the space for the drain we added
break;
} else if (ret == BLKPREP_KILL) {
rq->cmd_flags |= REQ_QUIET;
+ /*
+ * Mark this request as started so we don't trigger
+ * any debug logic in the end I/O path.
+ */
+ blk_start_request(rq);
__blk_end_request_all(rq, -EIO);
} else {
printk(KERN_ERR "%s: bad return=%d\n", __func__, ret);
return rq;
}
-EXPORT_SYMBOL(elv_next_request);
+EXPORT_SYMBOL(blk_peek_request);
-void elv_dequeue_request(struct request_queue *q, struct request *rq)
+void blk_dequeue_request(struct request *rq)
{
+ struct request_queue *q = rq->q;
+
BUG_ON(list_empty(&rq->queuelist));
BUG_ON(ELV_ON_HASH(rq));
* and to it is freed is accounted as io that is in progress at
* the driver side.
*/
- if (blk_account_rq(rq))
- q->in_flight++;
+ if (blk_account_rq(rq)) {
+ q->in_flight[rq_is_sync(rq)]++;
+ /*
+ * Mark this device as supporting hardware queuing, if
+ * we have more IOs in flight than 4.
+ */
+ if (!blk_queue_queuing(q) && queue_in_flight(q) > 4)
+ set_bit(QUEUE_FLAG_CQ, &q->queue_flags);
+ }
+}
+
+/**
+ * blk_start_request - start request processing on the driver
+ * @req: request to dequeue
+ *
+ * Description:
+ * Dequeue @req and start timeout timer on it. This hands off the
+ * request to the driver.
+ *
+ * Block internal functions which don't want to start timer should
+ * call blk_dequeue_request().
+ *
+ * Context:
+ * queue_lock must be held.
+ */
+void blk_start_request(struct request *req)
+{
+ blk_dequeue_request(req);
+
+ /*
+ * We are now handing the request to the hardware, initialize
+ * resid_len to full count and add the timeout handler.
+ */
+ req->resid_len = blk_rq_bytes(req);
+ if (unlikely(blk_bidi_rq(req)))
+ req->next_rq->resid_len = blk_rq_bytes(req->next_rq);
+
+ blk_add_timer(req);
}
+EXPORT_SYMBOL(blk_start_request);
+
+/**
+ * blk_fetch_request - fetch a request from a request queue
+ * @q: request queue to fetch a request from
+ *
+ * Description:
+ * Return the request at the top of @q. The request is started on
+ * return and LLD can start processing it immediately.
+ *
+ * Return:
+ * Pointer to the request at the top of @q if available. Null
+ * otherwise.
+ *
+ * Context:
+ * queue_lock must be held.
+ */
+struct request *blk_fetch_request(struct request_queue *q)
+{
+ struct request *rq;
+
+ rq = blk_peek_request(q);
+ if (rq)
+ blk_start_request(rq);
+ return rq;
+}
+EXPORT_SYMBOL(blk_fetch_request);
/**
* blk_update_request - Special helper function for request stacking drivers
- * @rq: the request being processed
+ * @req: the request being processed
* @error: %0 for success, < %0 for error
- * @nr_bytes: number of bytes to complete @rq
+ * @nr_bytes: number of bytes to complete @req
*
* Description:
- * Ends I/O on a number of bytes attached to @rq, but doesn't complete
- * the request structure even if @rq doesn't have leftover.
- * If @rq has leftover, sets it up for the next range of segments.
+ * Ends I/O on a number of bytes attached to @req, but doesn't complete
+ * the request structure even if @req doesn't have leftover.
+ * If @req has leftover, sets it up for the next range of segments.
*
* This special helper function is only for request stacking drivers
* (e.g. request-based dm) so that they can handle partial completion.
if (error && (blk_fs_request(req) && !(req->cmd_flags & REQ_QUIET))) {
printk(KERN_ERR "end_request: I/O error, dev %s, sector %llu\n",
req->rq_disk ? req->rq_disk->disk_name : "?",
- (unsigned long long)req->sector);
+ (unsigned long long)blk_rq_pos(req));
}
blk_account_io_completion(req, nr_bytes);
} else {
int idx = bio->bi_idx + next_idx;
- if (unlikely(bio->bi_idx >= bio->bi_vcnt)) {
+ if (unlikely(idx >= bio->bi_vcnt)) {
blk_dump_rq_flags(req, "__end_that");
printk(KERN_ERR "%s: bio idx %d >= vcnt %d\n",
- __func__, bio->bi_idx, bio->bi_vcnt);
+ __func__, idx, bio->bi_vcnt);
break;
}
* can find how many bytes remain in the request
* later.
*/
- req->nr_sectors = req->hard_nr_sectors = 0;
- req->current_nr_sectors = req->hard_cur_sectors = 0;
+ req->__data_len = 0;
return false;
}
bio_iovec(bio)->bv_len -= nr_bytes;
}
- blk_recalc_rq_sectors(req, total_bytes >> 9);
+ req->__data_len -= total_bytes;
+ req->buffer = bio_data(req->bio);
+
+ /* update sector only for requests with clear definition of sector */
+ if (blk_fs_request(req) || blk_discard_rq(req))
+ req->__sector += total_bytes >> 9;
+
+ /* mixed attributes always follow the first bio */
+ if (req->cmd_flags & REQ_MIXED_MERGE) {
+ req->cmd_flags &= ~REQ_FAILFAST_MASK;
+ req->cmd_flags |= req->bio->bi_rw & REQ_FAILFAST_MASK;
+ }
+
+ /*
+ * If total number of sectors is less than the first segment
+ * size, something has gone terribly wrong.
+ */
+ if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) {
+ printk(KERN_ERR "blk: request botched\n");
+ req->__data_len = blk_rq_cur_bytes(req);
+ }
+
+ /* recalculate the number of segments */
blk_recalc_rq_segments(req);
+
return true;
}
EXPORT_SYMBOL_GPL(blk_update_request);
if (blk_rq_tagged(req))
blk_queue_end_tag(req->q, req);
- if (blk_queued_rq(req))
- elv_dequeue_request(req->q, req);
+ BUG_ON(blk_queued_rq(req));
if (unlikely(laptop_mode) && blk_fs_request(req))
laptop_io_completion();
* %false - we are done with this request
* %true - still buffers pending for this request
**/
-bool blk_end_bidi_request(struct request *rq, int error,
- unsigned int nr_bytes, unsigned int bidi_bytes)
+static bool blk_end_bidi_request(struct request *rq, int error,
+ unsigned int nr_bytes, unsigned int bidi_bytes)
{
struct request_queue *q = rq->q;
unsigned long flags;
return false;
}
-EXPORT_SYMBOL_GPL(blk_end_bidi_request);
/**
* __blk_end_bidi_request - Complete a bidi request with queue lock held
* %false - we are done with this request
* %true - still buffers pending for this request
**/
-bool __blk_end_bidi_request(struct request *rq, int error,
- unsigned int nr_bytes, unsigned int bidi_bytes)
+static bool __blk_end_bidi_request(struct request *rq, int error,
+ unsigned int nr_bytes, unsigned int bidi_bytes)
{
if (blk_update_bidi_request(rq, error, nr_bytes, bidi_bytes))
return true;
return false;
}
-EXPORT_SYMBOL_GPL(__blk_end_bidi_request);
+
+/**
+ * blk_end_request - Helper function for drivers to complete the request.
+ * @rq: the request being processed
+ * @error: %0 for success, < %0 for error
+ * @nr_bytes: number of bytes to complete
+ *
+ * Description:
+ * Ends I/O on a number of bytes attached to @rq.
+ * If @rq has leftover, sets it up for the next range of segments.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ **/
+bool blk_end_request(struct request *rq, int error, unsigned int nr_bytes)
+{
+ return blk_end_bidi_request(rq, error, nr_bytes, 0);
+}
+EXPORT_SYMBOL(blk_end_request);
+
+/**
+ * blk_end_request_all - Helper function for drives to finish the request.
+ * @rq: the request to finish
+ * @error: %0 for success, < %0 for error
+ *
+ * Description:
+ * Completely finish @rq.
+ */
+void blk_end_request_all(struct request *rq, int error)
+{
+ bool pending;
+ unsigned int bidi_bytes = 0;
+
+ if (unlikely(blk_bidi_rq(rq)))
+ bidi_bytes = blk_rq_bytes(rq->next_rq);
+
+ pending = blk_end_bidi_request(rq, error, blk_rq_bytes(rq), bidi_bytes);
+ BUG_ON(pending);
+}
+EXPORT_SYMBOL(blk_end_request_all);
+
+/**
+ * blk_end_request_cur - Helper function to finish the current request chunk.
+ * @rq: the request to finish the current chunk for
+ * @error: %0 for success, < %0 for error
+ *
+ * Description:
+ * Complete the current consecutively mapped chunk from @rq.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ */
+bool blk_end_request_cur(struct request *rq, int error)
+{
+ return blk_end_request(rq, error, blk_rq_cur_bytes(rq));
+}
+EXPORT_SYMBOL(blk_end_request_cur);
+
+/**
+ * blk_end_request_err - Finish a request till the next failure boundary.
+ * @rq: the request to finish till the next failure boundary for
+ * @error: must be negative errno
+ *
+ * Description:
+ * Complete @rq till the next failure boundary.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ */
+bool blk_end_request_err(struct request *rq, int error)
+{
+ WARN_ON(error >= 0);
+ return blk_end_request(rq, error, blk_rq_err_bytes(rq));
+}
+EXPORT_SYMBOL_GPL(blk_end_request_err);
+
+/**
+ * __blk_end_request - Helper function for drivers to complete the request.
+ * @rq: the request being processed
+ * @error: %0 for success, < %0 for error
+ * @nr_bytes: number of bytes to complete
+ *
+ * Description:
+ * Must be called with queue lock held unlike blk_end_request().
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ **/
+bool __blk_end_request(struct request *rq, int error, unsigned int nr_bytes)
+{
+ return __blk_end_bidi_request(rq, error, nr_bytes, 0);
+}
+EXPORT_SYMBOL(__blk_end_request);
+
+/**
+ * __blk_end_request_all - Helper function for drives to finish the request.
+ * @rq: the request to finish
+ * @error: %0 for success, < %0 for error
+ *
+ * Description:
+ * Completely finish @rq. Must be called with queue lock held.
+ */
+void __blk_end_request_all(struct request *rq, int error)
+{
+ bool pending;
+ unsigned int bidi_bytes = 0;
+
+ if (unlikely(blk_bidi_rq(rq)))
+ bidi_bytes = blk_rq_bytes(rq->next_rq);
+
+ pending = __blk_end_bidi_request(rq, error, blk_rq_bytes(rq), bidi_bytes);
+ BUG_ON(pending);
+}
+EXPORT_SYMBOL(__blk_end_request_all);
+
+/**
+ * __blk_end_request_cur - Helper function to finish the current request chunk.
+ * @rq: the request to finish the current chunk for
+ * @error: %0 for success, < %0 for error
+ *
+ * Description:
+ * Complete the current consecutively mapped chunk from @rq. Must
+ * be called with queue lock held.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ */
+bool __blk_end_request_cur(struct request *rq, int error)
+{
+ return __blk_end_request(rq, error, blk_rq_cur_bytes(rq));
+}
+EXPORT_SYMBOL(__blk_end_request_cur);
+
+/**
+ * __blk_end_request_err - Finish a request till the next failure boundary.
+ * @rq: the request to finish till the next failure boundary for
+ * @error: must be negative errno
+ *
+ * Description:
+ * Complete @rq till the next failure boundary. Must be called
+ * with queue lock held.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ */
+bool __blk_end_request_err(struct request *rq, int error)
+{
+ WARN_ON(error >= 0);
+ return __blk_end_request(rq, error, blk_rq_err_bytes(rq));
+}
+EXPORT_SYMBOL_GPL(__blk_end_request_err);
void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
struct bio *bio)
{
- /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw, and
- we want BIO_RW_AHEAD (bit 1) to imply REQ_FAILFAST (bit 1). */
- rq->cmd_flags |= (bio->bi_rw & 3);
+ /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw */
+ rq->cmd_flags |= bio->bi_rw & REQ_RW;
if (bio_has_data(bio)) {
rq->nr_phys_segments = bio_phys_segments(q, bio);
rq->buffer = bio_data(bio);
}
- rq->current_nr_sectors = bio_cur_sectors(bio);
- rq->hard_cur_sectors = rq->current_nr_sectors;
- rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio);
- rq->data_len = bio->bi_size;
-
+ rq->__data_len = bio->bi_size;
rq->bio = rq->biotail = bio;
if (bio->bi_bdev)
}
EXPORT_SYMBOL_GPL(blk_lld_busy);
+/**
+ * blk_rq_unprep_clone - Helper function to free all bios in a cloned request
+ * @rq: the clone request to be cleaned up
+ *
+ * Description:
+ * Free all bios in @rq for a cloned request.
+ */
+void blk_rq_unprep_clone(struct request *rq)
+{
+ struct bio *bio;
+
+ while ((bio = rq->bio) != NULL) {
+ rq->bio = bio->bi_next;
+
+ bio_put(bio);
+ }
+}
+EXPORT_SYMBOL_GPL(blk_rq_unprep_clone);
+
+/*
+ * Copy attributes of the original request to the clone request.
+ * The actual data parts (e.g. ->cmd, ->buffer, ->sense) are not copied.
+ */
+static void __blk_rq_prep_clone(struct request *dst, struct request *src)
+{
+ dst->cpu = src->cpu;
+ dst->cmd_flags = (rq_data_dir(src) | REQ_NOMERGE);
+ dst->cmd_type = src->cmd_type;
+ dst->__sector = blk_rq_pos(src);
+ dst->__data_len = blk_rq_bytes(src);
+ dst->nr_phys_segments = src->nr_phys_segments;
+ dst->ioprio = src->ioprio;
+ dst->extra_len = src->extra_len;
+}
+
+/**
+ * blk_rq_prep_clone - Helper function to setup clone request
+ * @rq: the request to be setup
+ * @rq_src: original request to be cloned
+ * @bs: bio_set that bios for clone are allocated from
+ * @gfp_mask: memory allocation mask for bio
+ * @bio_ctr: setup function to be called for each clone bio.
+ * Returns %0 for success, non %0 for failure.
+ * @data: private data to be passed to @bio_ctr
+ *
+ * Description:
+ * Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq.
+ * The actual data parts of @rq_src (e.g. ->cmd, ->buffer, ->sense)
+ * are not copied, and copying such parts is the caller's responsibility.
+ * Also, pages which the original bios are pointing to are not copied
+ * and the cloned bios just point same pages.
+ * So cloned bios must be completed before original bios, which means
+ * the caller must complete @rq before @rq_src.
+ */
+int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
+ struct bio_set *bs, gfp_t gfp_mask,
+ int (*bio_ctr)(struct bio *, struct bio *, void *),
+ void *data)
+{
+ struct bio *bio, *bio_src;
+
+ if (!bs)
+ bs = fs_bio_set;
+
+ blk_rq_init(NULL, rq);
+
+ __rq_for_each_bio(bio_src, rq_src) {
+ bio = bio_alloc_bioset(gfp_mask, bio_src->bi_max_vecs, bs);
+ if (!bio)
+ goto free_and_out;
+
+ __bio_clone(bio, bio_src);
+
+ if (bio_integrity(bio_src) &&
+ bio_integrity_clone(bio, bio_src, gfp_mask, bs))
+ goto free_and_out;
+
+ if (bio_ctr && bio_ctr(bio, bio_src, data))
+ goto free_and_out;
+
+ if (rq->bio) {
+ rq->biotail->bi_next = bio;
+ rq->biotail = bio;
+ } else
+ rq->bio = rq->biotail = bio;
+ }
+
+ __blk_rq_prep_clone(rq, rq_src);
+
+ return 0;
+
+free_and_out:
+ if (bio)
+ bio_free(bio, bs);
+ blk_rq_unprep_clone(rq);
+
+ return -ENOMEM;
+}
+EXPORT_SYMBOL_GPL(blk_rq_prep_clone);
+
int kblockd_schedule_work(struct request_queue *q, struct work_struct *work)
{
return queue_work(kblockd_workqueue, work);
int __init blk_dev_init(void)
{
+ BUILD_BUG_ON(__REQ_NR_BITS > 8 *
+ sizeof(((struct request *)0)->cmd_flags));
+
kblockd_workqueue = create_workqueue("kblockd");
if (!kblockd_workqueue)
panic("Failed to create kblockd\n");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff