Add some seperation between bio-based and request-based DM core code.
'struct mapped_device' and other DM core only structures and functions
have been moved to dm-core.h and all relevant DM core .c files have been
updated to include dm-core.h rather than dm.h
DM targets should _never_ include dm-core.h!
[block core merge conflict resolution from Stephen Rothwell]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
#
dm-mod-y += dm.o dm-table.o dm-target.o dm-linear.o dm-stripe.o \
- dm-ioctl.o dm-io.o dm-kcopyd.o dm-sysfs.o dm-stats.o
+ dm-ioctl.o dm-io.o dm-kcopyd.o dm-sysfs.o dm-stats.o \
+ dm-rq.o
dm-multipath-y += dm-path-selector.o dm-mpath.o
dm-snapshot-y += dm-snap.o dm-exception-store.o dm-snap-transient.o \
dm-snap-persistent.o
-#include "dm.h"
+#include "dm-core.h"
/*
* The kobject release method must not be placed in the module itself,
--- /dev/null
+/*
+ * Internal header file _only_ for device mapper core
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef DM_CORE_INTERNAL_H
+#define DM_CORE_INTERNAL_H
+
+#include <linux/kthread.h>
+#include <linux/ktime.h>
+#include <linux/blk-mq.h>
+
+#include <trace/events/block.h>
+
+#include "dm.h"
+
+#define DM_RESERVED_MAX_IOS 1024
+
+struct dm_kobject_holder {
+ struct kobject kobj;
+ struct completion completion;
+};
+
+/*
+ * DM core internal structure that used directly by dm.c and dm-rq.c
+ * DM targets must _not_ deference a mapped_device to directly access its members!
+ */
+struct mapped_device {
+ struct srcu_struct io_barrier;
+ struct mutex suspend_lock;
+
+ /*
+ * The current mapping (struct dm_table *).
+ * Use dm_get_live_table{_fast} or take suspend_lock for
+ * dereference.
+ */
+ void __rcu *map;
+
+ struct list_head table_devices;
+ struct mutex table_devices_lock;
+
+ unsigned long flags;
+
+ struct request_queue *queue;
+ int numa_node_id;
+
+ unsigned type;
+ /* Protect queue and type against concurrent access. */
+ struct mutex type_lock;
+
+ atomic_t holders;
+ atomic_t open_count;
+
+ struct dm_target *immutable_target;
+ struct target_type *immutable_target_type;
+
+ struct gendisk *disk;
+ char name[16];
+
+ void *interface_ptr;
+
+ /*
+ * A list of ios that arrived while we were suspended.
+ */
+ atomic_t pending[2];
+ wait_queue_head_t wait;
+ struct work_struct work;
+ spinlock_t deferred_lock;
+ struct bio_list deferred;
+
+ /*
+ * Event handling.
+ */
+ wait_queue_head_t eventq;
+ atomic_t event_nr;
+ atomic_t uevent_seq;
+ struct list_head uevent_list;
+ spinlock_t uevent_lock; /* Protect access to uevent_list */
+
+ /* the number of internal suspends */
+ unsigned internal_suspend_count;
+
+ /*
+ * Processing queue (flush)
+ */
+ struct workqueue_struct *wq;
+
+ /*
+ * io objects are allocated from here.
+ */
+ mempool_t *io_pool;
+ mempool_t *rq_pool;
+
+ struct bio_set *bs;
+
+ /*
+ * freeze/thaw support require holding onto a super block
+ */
+ struct super_block *frozen_sb;
+
+ /* forced geometry settings */
+ struct hd_geometry geometry;
+
+ struct block_device *bdev;
+
+ /* kobject and completion */
+ struct dm_kobject_holder kobj_holder;
+
+ /* zero-length flush that will be cloned and submitted to targets */
+ struct bio flush_bio;
+
+ struct dm_stats stats;
+
+ struct kthread_worker kworker;
+ struct task_struct *kworker_task;
+
+ /* for request-based merge heuristic in dm_request_fn() */
+ unsigned seq_rq_merge_deadline_usecs;
+ int last_rq_rw;
+ sector_t last_rq_pos;
+ ktime_t last_rq_start_time;
+
+ /* for blk-mq request-based DM support */
+ struct blk_mq_tag_set *tag_set;
+ bool use_blk_mq:1;
+ bool init_tio_pdu:1;
+};
+
+void dm_init_md_queue(struct mapped_device *md);
+void dm_init_normal_md_queue(struct mapped_device *md);
+int md_in_flight(struct mapped_device *md);
+void disable_write_same(struct mapped_device *md);
+
+static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
+{
+ return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
+}
+
+unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max);
+
+static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen)
+{
+ return !maxlen || strlen(result) + 1 >= maxlen;
+}
+
+#endif
* This file is released under the GPL.
*/
-#include "dm.h"
+#include "dm-core.h"
#include <linux/device-mapper.h>
* This file is released under the GPL.
*/
-#include "dm.h"
+#include "dm-core.h"
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/device-mapper.h>
#include <linux/dm-kcopyd.h>
-#include "dm.h"
+#include "dm-core.h"
#define SUB_JOB_SIZE 128
#define SPLIT_COUNT 8
#include <linux/device-mapper.h>
-#include "dm.h"
+#include "dm-rq.h"
#include "dm-path-selector.h"
#include "dm-uevent.h"
* during end I/O handling, since those clone requests don't have
* bio clones. If we queue them inside the multipath target,
* we need to make bio clones, that requires memory allocation.
- * (See drivers/md/dm.c:end_clone_bio() about why the clone requests
+ * (See drivers/md/dm-rq.c:end_clone_bio() about why the clone requests
* don't have bio clones.)
* Instead of queueing the clone request here, we queue the original
* request into dm core, which will remake a clone request and
--- /dev/null
+/*
+ * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the GPL.
+ */
+
+#include "dm-core.h"
+#include "dm-rq.h"
+
+#include <linux/elevator.h> /* for rq_end_sector() */
+#include <linux/blk-mq.h>
+
+#define DM_MSG_PREFIX "core-rq"
+
+#define DM_MQ_NR_HW_QUEUES 1
+#define DM_MQ_QUEUE_DEPTH 2048
+static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES;
+static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;
+
+/*
+ * Request-based DM's mempools' reserved IOs set by the user.
+ */
+#define RESERVED_REQUEST_BASED_IOS 256
+static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;
+
+#ifdef CONFIG_DM_MQ_DEFAULT
+static bool use_blk_mq = true;
+#else
+static bool use_blk_mq = false;
+#endif
+
+bool dm_use_blk_mq_default(void)
+{
+ return use_blk_mq;
+}
+
+bool dm_use_blk_mq(struct mapped_device *md)
+{
+ return md->use_blk_mq;
+}
+EXPORT_SYMBOL_GPL(dm_use_blk_mq);
+
+unsigned dm_get_reserved_rq_based_ios(void)
+{
+ return __dm_get_module_param(&reserved_rq_based_ios,
+ RESERVED_REQUEST_BASED_IOS, DM_RESERVED_MAX_IOS);
+}
+EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios);
+
+static unsigned dm_get_blk_mq_nr_hw_queues(void)
+{
+ return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32);
+}
+
+static unsigned dm_get_blk_mq_queue_depth(void)
+{
+ return __dm_get_module_param(&dm_mq_queue_depth,
+ DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH);
+}
+
+int dm_request_based(struct mapped_device *md)
+{
+ return blk_queue_stackable(md->queue);
+}
+
+static void dm_old_start_queue(struct request_queue *q)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (blk_queue_stopped(q))
+ blk_start_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+void dm_start_queue(struct request_queue *q)
+{
+ if (!q->mq_ops)
+ dm_old_start_queue(q);
+ else {
+ blk_mq_start_stopped_hw_queues(q, true);
+ blk_mq_kick_requeue_list(q);
+ }
+}
+
+static void dm_old_stop_queue(struct request_queue *q)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (blk_queue_stopped(q)) {
+ spin_unlock_irqrestore(q->queue_lock, flags);
+ return;
+ }
+
+ blk_stop_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+void dm_stop_queue(struct request_queue *q)
+{
+ if (!q->mq_ops)
+ dm_old_stop_queue(q);
+ else
+ blk_mq_stop_hw_queues(q);
+}
+
+static struct dm_rq_target_io *alloc_old_rq_tio(struct mapped_device *md,
+ gfp_t gfp_mask)
+{
+ return mempool_alloc(md->io_pool, gfp_mask);
+}
+
+static void free_old_rq_tio(struct dm_rq_target_io *tio)
+{
+ mempool_free(tio, tio->md->io_pool);
+}
+
+static struct request *alloc_old_clone_request(struct mapped_device *md,
+ gfp_t gfp_mask)
+{
+ return mempool_alloc(md->rq_pool, gfp_mask);
+}
+
+static void free_old_clone_request(struct mapped_device *md, struct request *rq)
+{
+ mempool_free(rq, md->rq_pool);
+}
+
+/*
+ * Partial completion handling for request-based dm
+ */
+static void end_clone_bio(struct bio *clone)
+{
+ struct dm_rq_clone_bio_info *info =
+ container_of(clone, struct dm_rq_clone_bio_info, clone);
+ struct dm_rq_target_io *tio = info->tio;
+ struct bio *bio = info->orig;
+ unsigned int nr_bytes = info->orig->bi_iter.bi_size;
+ int error = clone->bi_error;
+
+ bio_put(clone);
+
+ if (tio->error)
+ /*
+ * An error has already been detected on the request.
+ * Once error occurred, just let clone->end_io() handle
+ * the remainder.
+ */
+ return;
+ else if (error) {
+ /*
+ * Don't notice the error to the upper layer yet.
+ * The error handling decision is made by the target driver,
+ * when the request is completed.
+ */
+ tio->error = error;
+ return;
+ }
+
+ /*
+ * I/O for the bio successfully completed.
+ * Notice the data completion to the upper layer.
+ */
+
+ /*
+ * bios are processed from the head of the list.
+ * So the completing bio should always be rq->bio.
+ * If it's not, something wrong is happening.
+ */
+ if (tio->orig->bio != bio)
+ DMERR("bio completion is going in the middle of the request");
+
+ /*
+ * Update the original request.
+ * Do not use blk_end_request() here, because it may complete
+ * the original request before the clone, and break the ordering.
+ */
+ blk_update_request(tio->orig, 0, nr_bytes);
+}
+
+static struct dm_rq_target_io *tio_from_request(struct request *rq)
+{
+ return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special);
+}
+
+static void rq_end_stats(struct mapped_device *md, struct request *orig)
+{
+ if (unlikely(dm_stats_used(&md->stats))) {
+ struct dm_rq_target_io *tio = tio_from_request(orig);
+ tio->duration_jiffies = jiffies - tio->duration_jiffies;
+ dm_stats_account_io(&md->stats, rq_data_dir(orig),
+ blk_rq_pos(orig), tio->n_sectors, true,
+ tio->duration_jiffies, &tio->stats_aux);
+ }
+}
+
+/*
+ * Don't touch any member of the md after calling this function because
+ * the md may be freed in dm_put() at the end of this function.
+ * Or do dm_get() before calling this function and dm_put() later.
+ */
+static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
+{
+ atomic_dec(&md->pending[rw]);
+
+ /* nudge anyone waiting on suspend queue */
+ if (!md_in_flight(md))
+ wake_up(&md->wait);
+
+ /*
+ * Run this off this callpath, as drivers could invoke end_io while
+ * inside their request_fn (and holding the queue lock). Calling
+ * back into ->request_fn() could deadlock attempting to grab the
+ * queue lock again.
+ */
+ if (!md->queue->mq_ops && run_queue)
+ blk_run_queue_async(md->queue);
+
+ /*
+ * dm_put() must be at the end of this function. See the comment above
+ */
+ dm_put(md);
+}
+
+static void free_rq_clone(struct request *clone)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ struct mapped_device *md = tio->md;
+
+ blk_rq_unprep_clone(clone);
+
+ if (md->type == DM_TYPE_MQ_REQUEST_BASED)
+ /* stacked on blk-mq queue(s) */
+ tio->ti->type->release_clone_rq(clone);
+ else if (!md->queue->mq_ops)
+ /* request_fn queue stacked on request_fn queue(s) */
+ free_old_clone_request(md, clone);
+
+ if (!md->queue->mq_ops)
+ free_old_rq_tio(tio);
+}
+
+/*
+ * Complete the clone and the original request.
+ * Must be called without clone's queue lock held,
+ * see end_clone_request() for more details.
+ */
+static void dm_end_request(struct request *clone, int error)
+{
+ int rw = rq_data_dir(clone);
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ struct mapped_device *md = tio->md;
+ struct request *rq = tio->orig;
+
+ if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
+ rq->errors = clone->errors;
+ rq->resid_len = clone->resid_len;
+
+ if (rq->sense)
+ /*
+ * We are using the sense buffer of the original
+ * request.
+ * So setting the length of the sense data is enough.
+ */
+ rq->sense_len = clone->sense_len;
+ }
+
+ free_rq_clone(clone);
+ rq_end_stats(md, rq);
+ if (!rq->q->mq_ops)
+ blk_end_request_all(rq, error);
+ else
+ blk_mq_end_request(rq, error);
+ rq_completed(md, rw, true);
+}
+
+static void dm_unprep_request(struct request *rq)
+{
+ struct dm_rq_target_io *tio = tio_from_request(rq);
+ struct request *clone = tio->clone;
+
+ if (!rq->q->mq_ops) {
+ rq->special = NULL;
+ rq->cmd_flags &= ~REQ_DONTPREP;
+ }
+
+ if (clone)
+ free_rq_clone(clone);
+ else if (!tio->md->queue->mq_ops)
+ free_old_rq_tio(tio);
+}
+
+/*
+ * Requeue the original request of a clone.
+ */
+static void dm_old_requeue_request(struct request *rq)
+{
+ struct request_queue *q = rq->q;
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ blk_requeue_request(q, rq);
+ blk_run_queue_async(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+static void dm_mq_requeue_request(struct request *rq)
+{
+ struct request_queue *q = rq->q;
+ unsigned long flags;
+
+ blk_mq_requeue_request(rq);
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (!blk_queue_stopped(q))
+ blk_mq_kick_requeue_list(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+static void dm_requeue_original_request(struct mapped_device *md,
+ struct request *rq)
+{
+ int rw = rq_data_dir(rq);
+
+ rq_end_stats(md, rq);
+ dm_unprep_request(rq);
+
+ if (!rq->q->mq_ops)
+ dm_old_requeue_request(rq);
+ else
+ dm_mq_requeue_request(rq);
+
+ rq_completed(md, rw, false);
+}
+
+static void dm_done(struct request *clone, int error, bool mapped)
+{
+ int r = error;
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ dm_request_endio_fn rq_end_io = NULL;
+
+ if (tio->ti) {
+ rq_end_io = tio->ti->type->rq_end_io;
+
+ if (mapped && rq_end_io)
+ r = rq_end_io(tio->ti, clone, error, &tio->info);
+ }
+
+ if (unlikely(r == -EREMOTEIO && (req_op(clone) == REQ_OP_WRITE_SAME) &&
+ !clone->q->limits.max_write_same_sectors))
+ disable_write_same(tio->md);
+
+ if (r <= 0)
+ /* The target wants to complete the I/O */
+ dm_end_request(clone, r);
+ else if (r == DM_ENDIO_INCOMPLETE)
+ /* The target will handle the I/O */
+ return;
+ else if (r == DM_ENDIO_REQUEUE)
+ /* The target wants to requeue the I/O */
+ dm_requeue_original_request(tio->md, tio->orig);
+ else {
+ DMWARN("unimplemented target endio return value: %d", r);
+ BUG();
+ }
+}
+
+/*
+ * Request completion handler for request-based dm
+ */
+static void dm_softirq_done(struct request *rq)
+{
+ bool mapped = true;
+ struct dm_rq_target_io *tio = tio_from_request(rq);
+ struct request *clone = tio->clone;
+ int rw;
+
+ if (!clone) {
+ rq_end_stats(tio->md, rq);
+ rw = rq_data_dir(rq);
+ if (!rq->q->mq_ops) {
+ blk_end_request_all(rq, tio->error);
+ rq_completed(tio->md, rw, false);
+ free_old_rq_tio(tio);
+ } else {
+ blk_mq_end_request(rq, tio->error);
+ rq_completed(tio->md, rw, false);
+ }
+ return;
+ }
+
+ if (rq->cmd_flags & REQ_FAILED)
+ mapped = false;
+
+ dm_done(clone, tio->error, mapped);
+}
+
+/*
+ * Complete the clone and the original request with the error status
+ * through softirq context.
+ */
+static void dm_complete_request(struct request *rq, int error)
+{
+ struct dm_rq_target_io *tio = tio_from_request(rq);
+
+ tio->error = error;
+ if (!rq->q->mq_ops)
+ blk_complete_request(rq);
+ else
+ blk_mq_complete_request(rq, error);
+}
+
+/*
+ * Complete the not-mapped clone and the original request with the error status
+ * through softirq context.
+ * Target's rq_end_io() function isn't called.
+ * This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
+ */
+static void dm_kill_unmapped_request(struct request *rq, int error)
+{
+ rq->cmd_flags |= REQ_FAILED;
+ dm_complete_request(rq, error);
+}
+
+/*
+ * Called with the clone's queue lock held (in the case of .request_fn)
+ */
+static void end_clone_request(struct request *clone, int error)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+
+ if (!clone->q->mq_ops) {
+ /*
+ * For just cleaning up the information of the queue in which
+ * the clone was dispatched.
+ * The clone is *NOT* freed actually here because it is alloced
+ * from dm own mempool (REQ_ALLOCED isn't set).
+ */
+ __blk_put_request(clone->q, clone);
+ }
+
+ /*
+ * Actual request completion is done in a softirq context which doesn't
+ * hold the clone's queue lock. Otherwise, deadlock could occur because:
+ * - another request may be submitted by the upper level driver
+ * of the stacking during the completion
+ * - the submission which requires queue lock may be done
+ * against this clone's queue
+ */
+ dm_complete_request(tio->orig, error);
+}
+
+static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
+{
+ int r;
+
+ if (blk_queue_io_stat(clone->q))
+ clone->cmd_flags |= REQ_IO_STAT;
+
+ clone->start_time = jiffies;
+ r = blk_insert_cloned_request(clone->q, clone);
+ if (r)
+ /* must complete clone in terms of original request */
+ dm_complete_request(rq, r);
+}
+
+static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
+ void *data)
+{
+ struct dm_rq_target_io *tio = data;
+ struct dm_rq_clone_bio_info *info =
+ container_of(bio, struct dm_rq_clone_bio_info, clone);
+
+ info->orig = bio_orig;
+ info->tio = tio;
+ bio->bi_end_io = end_clone_bio;
+
+ return 0;
+}
+
+static int setup_clone(struct request *clone, struct request *rq,
+ struct dm_rq_target_io *tio, gfp_t gfp_mask)
+{
+ int r;
+
+ r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
+ dm_rq_bio_constructor, tio);
+ if (r)
+ return r;
+
+ clone->cmd = rq->cmd;
+ clone->cmd_len = rq->cmd_len;
+ clone->sense = rq->sense;
+ clone->end_io = end_clone_request;
+ clone->end_io_data = tio;
+
+ tio->clone = clone;
+
+ return 0;
+}
+
+static struct request *clone_old_rq(struct request *rq, struct mapped_device *md,
+ struct dm_rq_target_io *tio, gfp_t gfp_mask)
+{
+ /*
+ * Create clone for use with .request_fn request_queue
+ */
+ struct request *clone;
+
+ clone = alloc_old_clone_request(md, gfp_mask);
+ if (!clone)
+ return NULL;
+
+ blk_rq_init(NULL, clone);
+ if (setup_clone(clone, rq, tio, gfp_mask)) {
+ /* -ENOMEM */
+ free_old_clone_request(md, clone);
+ return NULL;
+ }
+
+ return clone;
+}
+
+static void map_tio_request(struct kthread_work *work);
+
+static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
+ struct mapped_device *md)
+{
+ tio->md = md;
+ tio->ti = NULL;
+ tio->clone = NULL;
+ tio->orig = rq;
+ tio->error = 0;
+ /*
+ * Avoid initializing info for blk-mq; it passes
+ * target-specific data through info.ptr
+ * (see: dm_mq_init_request)
+ */
+ if (!md->init_tio_pdu)
+ memset(&tio->info, 0, sizeof(tio->info));
+ if (md->kworker_task)
+ init_kthread_work(&tio->work, map_tio_request);
+}
+
+static struct dm_rq_target_io *dm_old_prep_tio(struct request *rq,
+ struct mapped_device *md,
+ gfp_t gfp_mask)
+{
+ struct dm_rq_target_io *tio;
+ int srcu_idx;
+ struct dm_table *table;
+
+ tio = alloc_old_rq_tio(md, gfp_mask);
+ if (!tio)
+ return NULL;
+
+ init_tio(tio, rq, md);
+
+ table = dm_get_live_table(md, &srcu_idx);
+ /*
+ * Must clone a request if this .request_fn DM device
+ * is stacked on .request_fn device(s).
+ */
+ if (!dm_table_mq_request_based(table)) {
+ if (!clone_old_rq(rq, md, tio, gfp_mask)) {
+ dm_put_live_table(md, srcu_idx);
+ free_old_rq_tio(tio);
+ return NULL;
+ }
+ }
+ dm_put_live_table(md, srcu_idx);
+
+ return tio;
+}
+
+/*
+ * Called with the queue lock held.
+ */
+static int dm_old_prep_fn(struct request_queue *q, struct request *rq)
+{
+ struct mapped_device *md = q->queuedata;
+ struct dm_rq_target_io *tio;
+
+ if (unlikely(rq->special)) {
+ DMWARN("Already has something in rq->special.");
+ return BLKPREP_KILL;
+ }
+
+ tio = dm_old_prep_tio(rq, md, GFP_ATOMIC);
+ if (!tio)
+ return BLKPREP_DEFER;
+
+ rq->special = tio;
+ rq->cmd_flags |= REQ_DONTPREP;
+
+ return BLKPREP_OK;
+}
+
+/*
+ * Returns:
+ * 0 : the request has been processed
+ * DM_MAPIO_REQUEUE : the original request needs to be requeued
+ * < 0 : the request was completed due to failure
+ */
+static int map_request(struct dm_rq_target_io *tio, struct request *rq,
+ struct mapped_device *md)
+{
+ int r;
+ struct dm_target *ti = tio->ti;
+ struct request *clone = NULL;
+
+ if (tio->clone) {
+ clone = tio->clone;
+ r = ti->type->map_rq(ti, clone, &tio->info);
+ } else {
+ r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone);
+ if (r < 0) {
+ /* The target wants to complete the I/O */
+ dm_kill_unmapped_request(rq, r);
+ return r;
+ }
+ if (r != DM_MAPIO_REMAPPED)
+ return r;
+ if (setup_clone(clone, rq, tio, GFP_ATOMIC)) {
+ /* -ENOMEM */
+ ti->type->release_clone_rq(clone);
+ return DM_MAPIO_REQUEUE;
+ }
+ }
+
+ switch (r) {
+ case DM_MAPIO_SUBMITTED:
+ /* The target has taken the I/O to submit by itself later */
+ break;
+ case DM_MAPIO_REMAPPED:
+ /* The target has remapped the I/O so dispatch it */
+ trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
+ blk_rq_pos(rq));
+ dm_dispatch_clone_request(clone, rq);
+ break;
+ case DM_MAPIO_REQUEUE:
+ /* The target wants to requeue the I/O */
+ dm_requeue_original_request(md, tio->orig);
+ break;
+ default:
+ if (r > 0) {
+ DMWARN("unimplemented target map return value: %d", r);
+ BUG();
+ }
+
+ /* The target wants to complete the I/O */
+ dm_kill_unmapped_request(rq, r);
+ return r;
+ }
+
+ return 0;
+}
+
+static void dm_start_request(struct mapped_device *md, struct request *orig)
+{
+ if (!orig->q->mq_ops)
+ blk_start_request(orig);
+ else
+ blk_mq_start_request(orig);
+ atomic_inc(&md->pending[rq_data_dir(orig)]);
+
+ if (md->seq_rq_merge_deadline_usecs) {
+ md->last_rq_pos = rq_end_sector(orig);
+ md->last_rq_rw = rq_data_dir(orig);
+ md->last_rq_start_time = ktime_get();
+ }
+
+ if (unlikely(dm_stats_used(&md->stats))) {
+ struct dm_rq_target_io *tio = tio_from_request(orig);
+ tio->duration_jiffies = jiffies;
+ tio->n_sectors = blk_rq_sectors(orig);
+ dm_stats_account_io(&md->stats, rq_data_dir(orig),
+ blk_rq_pos(orig), tio->n_sectors, false, 0,
+ &tio->stats_aux);
+ }
+
+ /*
+ * Hold the md reference here for the in-flight I/O.
+ * We can't rely on the reference count by device opener,
+ * because the device may be closed during the request completion
+ * when all bios are completed.
+ * See the comment in rq_completed() too.
+ */
+ dm_get(md);
+}
+
+static void map_tio_request(struct kthread_work *work)
+{
+ struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work);
+ struct request *rq = tio->orig;
+ struct mapped_device *md = tio->md;
+
+ if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE)
+ dm_requeue_original_request(md, rq);
+}
+
+ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
+{
+ return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs);
+}
+
+#define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000
+
+ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
+ const char *buf, size_t count)
+{
+ unsigned deadline;
+
+ if (!dm_request_based(md) || md->use_blk_mq)
+ return count;
+
+ if (kstrtouint(buf, 10, &deadline))
+ return -EINVAL;
+
+ if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS)
+ deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS;
+
+ md->seq_rq_merge_deadline_usecs = deadline;
+
+ return count;
+}
+
+static bool dm_old_request_peeked_before_merge_deadline(struct mapped_device *md)
+{
+ ktime_t kt_deadline;
+
+ if (!md->seq_rq_merge_deadline_usecs)
+ return false;
+
+ kt_deadline = ns_to_ktime((u64)md->seq_rq_merge_deadline_usecs * NSEC_PER_USEC);
+ kt_deadline = ktime_add_safe(md->last_rq_start_time, kt_deadline);
+
+ return !ktime_after(ktime_get(), kt_deadline);
+}
+
+/*
+ * q->request_fn for old request-based dm.
+ * Called with the queue lock held.
+ */
+static void dm_old_request_fn(struct request_queue *q)
+{
+ struct mapped_device *md = q->queuedata;
+ struct dm_target *ti = md->immutable_target;
+ struct request *rq;
+ struct dm_rq_target_io *tio;
+ sector_t pos = 0;
+
+ if (unlikely(!ti)) {
+ int srcu_idx;
+ struct dm_table *map = dm_get_live_table(md, &srcu_idx);
+
+ ti = dm_table_find_target(map, pos);
+ dm_put_live_table(md, srcu_idx);
+ }
+
+ /*
+ * For suspend, check blk_queue_stopped() and increment
+ * ->pending within a single queue_lock not to increment the
+ * number of in-flight I/Os after the queue is stopped in
+ * dm_suspend().
+ */
+ while (!blk_queue_stopped(q)) {
+ rq = blk_peek_request(q);
+ if (!rq)
+ return;
+
+ /* always use block 0 to find the target for flushes for now */
+ pos = 0;
+ if (req_op(rq) != REQ_OP_FLUSH)
+ pos = blk_rq_pos(rq);
+
+ if ((dm_old_request_peeked_before_merge_deadline(md) &&
+ md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
+ md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
+ (ti->type->busy && ti->type->busy(ti))) {
+ blk_delay_queue(q, HZ / 100);
+ return;
+ }
+
+ dm_start_request(md, rq);
+
+ tio = tio_from_request(rq);
+ /* Establish tio->ti before queuing work (map_tio_request) */
+ tio->ti = ti;
+ queue_kthread_work(&md->kworker, &tio->work);
+ BUG_ON(!irqs_disabled());
+ }
+}
+
+/*
+ * Fully initialize a .request_fn request-based queue.
+ */
+int dm_old_init_request_queue(struct mapped_device *md)
+{
+ /* Fully initialize the queue */
+ if (!blk_init_allocated_queue(md->queue, dm_old_request_fn, NULL))
+ return -EINVAL;
+
+ /* disable dm_old_request_fn's merge heuristic by default */
+ md->seq_rq_merge_deadline_usecs = 0;
+
+ dm_init_normal_md_queue(md);
+ blk_queue_softirq_done(md->queue, dm_softirq_done);
+ blk_queue_prep_rq(md->queue, dm_old_prep_fn);
+
+ /* Initialize the request-based DM worker thread */
+ init_kthread_worker(&md->kworker);
+ md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
+ "kdmwork-%s", dm_device_name(md));
+
+ elv_register_queue(md->queue);
+
+ return 0;
+}
+
+static int dm_mq_init_request(void *data, struct request *rq,
+ unsigned int hctx_idx, unsigned int request_idx,
+ unsigned int numa_node)
+{
+ struct mapped_device *md = data;
+ struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
+
+ /*
+ * Must initialize md member of tio, otherwise it won't
+ * be available in dm_mq_queue_rq.
+ */
+ tio->md = md;
+
+ if (md->init_tio_pdu) {
+ /* target-specific per-io data is immediately after the tio */
+ tio->info.ptr = tio + 1;
+ }
+
+ return 0;
+}
+
+static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
+ const struct blk_mq_queue_data *bd)
+{
+ struct request *rq = bd->rq;
+ struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
+ struct mapped_device *md = tio->md;
+ struct dm_target *ti = md->immutable_target;
+
+ if (unlikely(!ti)) {
+ int srcu_idx;
+ struct dm_table *map = dm_get_live_table(md, &srcu_idx);
+
+ ti = dm_table_find_target(map, 0);
+ dm_put_live_table(md, srcu_idx);
+ }
+
+ if (ti->type->busy && ti->type->busy(ti))
+ return BLK_MQ_RQ_QUEUE_BUSY;
+
+ dm_start_request(md, rq);
+
+ /* Init tio using md established in .init_request */
+ init_tio(tio, rq, md);
+
+ /*
+ * Establish tio->ti before calling map_request().
+ */
+ tio->ti = ti;
+
+ /* Direct call is fine since .queue_rq allows allocations */
+ if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE) {
+ /* Undo dm_start_request() before requeuing */
+ rq_end_stats(md, rq);
+ rq_completed(md, rq_data_dir(rq), false);
+ return BLK_MQ_RQ_QUEUE_BUSY;
+ }
+
+ return BLK_MQ_RQ_QUEUE_OK;
+}
+
+static struct blk_mq_ops dm_mq_ops = {
+ .queue_rq = dm_mq_queue_rq,
+ .map_queue = blk_mq_map_queue,
+ .complete = dm_softirq_done,
+ .init_request = dm_mq_init_request,
+};
+
+int dm_mq_init_request_queue(struct mapped_device *md, struct dm_target *immutable_tgt)
+{
+ struct request_queue *q;
+ int err;
+
+ if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) {
+ DMERR("request-based dm-mq may only be stacked on blk-mq device(s)");
+ return -EINVAL;
+ }
+
+ md->tag_set = kzalloc_node(sizeof(struct blk_mq_tag_set), GFP_KERNEL, md->numa_node_id);
+ if (!md->tag_set)
+ return -ENOMEM;
+
+ md->tag_set->ops = &dm_mq_ops;
+ md->tag_set->queue_depth = dm_get_blk_mq_queue_depth();
+ md->tag_set->numa_node = md->numa_node_id;
+ md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
+ md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues();
+ md->tag_set->driver_data = md;
+
+ md->tag_set->cmd_size = sizeof(struct dm_rq_target_io);
+ if (immutable_tgt && immutable_tgt->per_io_data_size) {
+ /* any target-specific per-io data is immediately after the tio */
+ md->tag_set->cmd_size += immutable_tgt->per_io_data_size;
+ md->init_tio_pdu = true;
+ }
+
+ err = blk_mq_alloc_tag_set(md->tag_set);
+ if (err)
+ goto out_kfree_tag_set;
+
+ q = blk_mq_init_allocated_queue(md->tag_set, md->queue);
+ if (IS_ERR(q)) {
+ err = PTR_ERR(q);
+ goto out_tag_set;
+ }
+ dm_init_md_queue(md);
+
+ /* backfill 'mq' sysfs registration normally done in blk_register_queue */
+ blk_mq_register_disk(md->disk);
+
+ return 0;
+
+out_tag_set:
+ blk_mq_free_tag_set(md->tag_set);
+out_kfree_tag_set:
+ kfree(md->tag_set);
+
+ return err;
+}
+
+void dm_mq_cleanup_mapped_device(struct mapped_device *md)
+{
+ if (md->tag_set) {
+ blk_mq_free_tag_set(md->tag_set);
+ kfree(md->tag_set);
+ }
+}
+
+module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools");
+
+module_param(use_blk_mq, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(use_blk_mq, "Use block multiqueue for request-based DM devices");
+
+module_param(dm_mq_nr_hw_queues, uint, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dm_mq_nr_hw_queues, "Number of hardware queues for request-based dm-mq devices");
+
+module_param(dm_mq_queue_depth, uint, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dm_mq_queue_depth, "Queue depth for request-based dm-mq devices");
--- /dev/null
+/*
+ * Internal header file for device mapper
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef DM_RQ_INTERNAL_H
+#define DM_RQ_INTERNAL_H
+
+#include <linux/bio.h>
+#include <linux/kthread.h>
+
+#include "dm-stats.h"
+
+struct mapped_device;
+
+/*
+ * One of these is allocated per request.
+ */
+struct dm_rq_target_io {
+ struct mapped_device *md;
+ struct dm_target *ti;
+ struct request *orig, *clone;
+ struct kthread_work work;
+ int error;
+ union map_info info;
+ struct dm_stats_aux stats_aux;
+ unsigned long duration_jiffies;
+ unsigned n_sectors;
+};
+
+/*
+ * For request-based dm - the bio clones we allocate are embedded in these
+ * structs.
+ *
+ * We allocate these with bio_alloc_bioset, using the front_pad parameter when
+ * the bioset is created - this means the bio has to come at the end of the
+ * struct.
+ */
+struct dm_rq_clone_bio_info {
+ struct bio *orig;
+ struct dm_rq_target_io *tio;
+ struct bio clone;
+};
+
+bool dm_use_blk_mq_default(void);
+bool dm_use_blk_mq(struct mapped_device *md);
+
+int dm_old_init_request_queue(struct mapped_device *md);
+int dm_mq_init_request_queue(struct mapped_device *md, struct dm_target *immutable_tgt);
+void dm_mq_cleanup_mapped_device(struct mapped_device *md);
+
+void dm_start_queue(struct request_queue *q);
+void dm_stop_queue(struct request_queue *q);
+
+unsigned dm_get_reserved_rq_based_ios(void);
+
+ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf);
+ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
+ const char *buf, size_t count);
+
+#endif
#include <linux/module.h>
#include <linux/device-mapper.h>
-#include "dm.h"
+#include "dm-core.h"
#include "dm-stats.h"
#define DM_MSG_PREFIX "stats"
#include <linux/sysfs.h>
#include <linux/dm-ioctl.h>
-#include "dm.h"
+#include "dm-core.h"
+#include "dm-rq.h"
struct dm_sysfs_attr {
struct attribute attr;
* This file is released under the GPL.
*/
-#include "dm.h"
+#include "dm-core.h"
#include <linux/module.h>
#include <linux/vmalloc.h>
* This file is released under the GPL.
*/
-#include "dm.h"
+#include "dm-core.h"
#include <linux/module.h>
#include <linux/init.h>
* This file is released under the GPL.
*/
-#include "dm.h"
+#include "dm-core.h"
+#include "dm-rq.h"
#include "dm-uevent.h"
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
-#include <linux/moduleparam.h>
#include <linux/blkpg.h>
#include <linux/bio.h>
#include <linux/mempool.h>
#include <linux/hdreg.h>
#include <linux/delay.h>
#include <linux/wait.h>
-#include <linux/kthread.h>
-#include <linux/ktime.h>
-#include <linux/elevator.h> /* for rq_end_sector() */
-#include <linux/blk-mq.h>
#include <linux/pr.h>
-#include <trace/events/block.h>
-
#define DM_MSG_PREFIX "core"
#ifdef CONFIG_PRINTK
static struct workqueue_struct *deferred_remove_workqueue;
/*
- * For bio-based dm.
* One of these is allocated per bio.
*/
struct dm_io {
struct dm_stats_aux stats_aux;
};
-/*
- * For request-based dm.
- * One of these is allocated per request.
- */
-struct dm_rq_target_io {
- struct mapped_device *md;
- struct dm_target *ti;
- struct request *orig, *clone;
- struct kthread_work work;
- int error;
- union map_info info;
- struct dm_stats_aux stats_aux;
- unsigned long duration_jiffies;
- unsigned n_sectors;
-};
-
-/*
- * For request-based dm - the bio clones we allocate are embedded in these
- * structs.
- *
- * We allocate these with bio_alloc_bioset, using the front_pad parameter when
- * the bioset is created - this means the bio has to come at the end of the
- * struct.
- */
-struct dm_rq_clone_bio_info {
- struct bio *orig;
- struct dm_rq_target_io *tio;
- struct bio clone;
-};
-
#define MINOR_ALLOCED ((void *)-1)
/*
#define DMF_DEFERRED_REMOVE 6
#define DMF_SUSPENDED_INTERNALLY 7
-/*
- * Work processed by per-device workqueue.
- */
-struct mapped_device {
- struct srcu_struct io_barrier;
- struct mutex suspend_lock;
-
- /*
- * The current mapping (struct dm_table *).
- * Use dm_get_live_table{_fast} or take suspend_lock for
- * dereference.
- */
- void __rcu *map;
-
- struct list_head table_devices;
- struct mutex table_devices_lock;
-
- unsigned long flags;
-
- struct request_queue *queue;
- int numa_node_id;
-
- unsigned type;
- /* Protect queue and type against concurrent access. */
- struct mutex type_lock;
-
- atomic_t holders;
- atomic_t open_count;
-
- struct dm_target *immutable_target;
- struct target_type *immutable_target_type;
-
- struct gendisk *disk;
- char name[16];
-
- void *interface_ptr;
-
- /*
- * A list of ios that arrived while we were suspended.
- */
- atomic_t pending[2];
- wait_queue_head_t wait;
- struct work_struct work;
- spinlock_t deferred_lock;
- struct bio_list deferred;
-
- /*
- * Event handling.
- */
- wait_queue_head_t eventq;
- atomic_t event_nr;
- atomic_t uevent_seq;
- struct list_head uevent_list;
- spinlock_t uevent_lock; /* Protect access to uevent_list */
-
- /* the number of internal suspends */
- unsigned internal_suspend_count;
-
- /*
- * Processing queue (flush)
- */
- struct workqueue_struct *wq;
-
- /*
- * io objects are allocated from here.
- */
- mempool_t *io_pool;
- mempool_t *rq_pool;
-
- struct bio_set *bs;
-
- /*
- * freeze/thaw support require holding onto a super block
- */
- struct super_block *frozen_sb;
-
- /* forced geometry settings */
- struct hd_geometry geometry;
-
- struct block_device *bdev;
-
- /* kobject and completion */
- struct dm_kobject_holder kobj_holder;
-
- /* zero-length flush that will be cloned and submitted to targets */
- struct bio flush_bio;
-
- struct dm_stats stats;
-
- struct kthread_worker kworker;
- struct task_struct *kworker_task;
-
- /* for request-based merge heuristic in dm_request_fn() */
- unsigned seq_rq_merge_deadline_usecs;
- int last_rq_rw;
- sector_t last_rq_pos;
- ktime_t last_rq_start_time;
-
- /* for blk-mq request-based DM support */
- struct blk_mq_tag_set *tag_set;
- bool use_blk_mq:1;
- bool init_tio_pdu:1;
-};
-
-#ifdef CONFIG_DM_MQ_DEFAULT
-static bool use_blk_mq = true;
-#else
-static bool use_blk_mq = false;
-#endif
-
-#define DM_MQ_NR_HW_QUEUES 1
-#define DM_MQ_QUEUE_DEPTH 2048
#define DM_NUMA_NODE NUMA_NO_NODE
-
-static unsigned dm_mq_nr_hw_queues = DM_MQ_NR_HW_QUEUES;
-static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;
static int dm_numa_node = DM_NUMA_NODE;
-bool dm_use_blk_mq(struct mapped_device *md)
-{
- return md->use_blk_mq;
-}
-EXPORT_SYMBOL_GPL(dm_use_blk_mq);
-
/*
* For mempools pre-allocation at the table loading time.
*/
struct dm_dev dm_dev;
};
-#define RESERVED_BIO_BASED_IOS 16
-#define RESERVED_REQUEST_BASED_IOS 256
-#define RESERVED_MAX_IOS 1024
static struct kmem_cache *_io_cache;
static struct kmem_cache *_rq_tio_cache;
static struct kmem_cache *_rq_cache;
/*
* Bio-based DM's mempools' reserved IOs set by the user.
*/
+#define RESERVED_BIO_BASED_IOS 16
static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS;
-/*
- * Request-based DM's mempools' reserved IOs set by the user.
- */
-static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;
-
static int __dm_get_module_param_int(int *module_param, int min, int max)
{
int param = ACCESS_ONCE(*module_param);
return param;
}
-static unsigned __dm_get_module_param(unsigned *module_param,
- unsigned def, unsigned max)
+unsigned __dm_get_module_param(unsigned *module_param,
+ unsigned def, unsigned max)
{
unsigned param = ACCESS_ONCE(*module_param);
unsigned modified_param = 0;
unsigned dm_get_reserved_bio_based_ios(void)
{
return __dm_get_module_param(&reserved_bio_based_ios,
- RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS);
+ RESERVED_BIO_BASED_IOS, DM_RESERVED_MAX_IOS);
}
EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios);
-unsigned dm_get_reserved_rq_based_ios(void)
-{
- return __dm_get_module_param(&reserved_rq_based_ios,
- RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS);
-}
-EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios);
-
-static unsigned dm_get_blk_mq_nr_hw_queues(void)
-{
- return __dm_get_module_param(&dm_mq_nr_hw_queues, 1, 32);
-}
-
-static unsigned dm_get_blk_mq_queue_depth(void)
-{
- return __dm_get_module_param(&dm_mq_queue_depth,
- DM_MQ_QUEUE_DEPTH, BLK_MQ_MAX_DEPTH);
-}
-
static unsigned dm_get_numa_node(void)
{
return __dm_get_module_param_int(&dm_numa_node,
bio_put(&tio->clone);
}
-static struct dm_rq_target_io *alloc_old_rq_tio(struct mapped_device *md,
- gfp_t gfp_mask)
-{
- return mempool_alloc(md->io_pool, gfp_mask);
-}
-
-static void free_old_rq_tio(struct dm_rq_target_io *tio)
-{
- mempool_free(tio, tio->md->io_pool);
-}
-
-static struct request *alloc_old_clone_request(struct mapped_device *md,
- gfp_t gfp_mask)
-{
- return mempool_alloc(md->rq_pool, gfp_mask);
-}
-
-static void free_old_clone_request(struct mapped_device *md, struct request *rq)
-{
- mempool_free(rq, md->rq_pool);
-}
-
-static int md_in_flight(struct mapped_device *md)
+int md_in_flight(struct mapped_device *md)
{
return atomic_read(&md->pending[READ]) +
atomic_read(&md->pending[WRITE]);
}
}
-static void disable_write_same(struct mapped_device *md)
+void disable_write_same(struct mapped_device *md)
{
struct queue_limits *limits = dm_get_queue_limits(md);
dec_pending(io, error);
}
-/*
- * Partial completion handling for request-based dm
- */
-static void end_clone_bio(struct bio *clone)
-{
- struct dm_rq_clone_bio_info *info =
- container_of(clone, struct dm_rq_clone_bio_info, clone);
- struct dm_rq_target_io *tio = info->tio;
- struct bio *bio = info->orig;
- unsigned int nr_bytes = info->orig->bi_iter.bi_size;
- int error = clone->bi_error;
-
- bio_put(clone);
-
- if (tio->error)
- /*
- * An error has already been detected on the request.
- * Once error occurred, just let clone->end_io() handle
- * the remainder.
- */
- return;
- else if (error) {
- /*
- * Don't notice the error to the upper layer yet.
- * The error handling decision is made by the target driver,
- * when the request is completed.
- */
- tio->error = error;
- return;
- }
-
- /*
- * I/O for the bio successfully completed.
- * Notice the data completion to the upper layer.
- */
-
- /*
- * bios are processed from the head of the list.
- * So the completing bio should always be rq->bio.
- * If it's not, something wrong is happening.
- */
- if (tio->orig->bio != bio)
- DMERR("bio completion is going in the middle of the request");
-
- /*
- * Update the original request.
- * Do not use blk_end_request() here, because it may complete
- * the original request before the clone, and break the ordering.
- */
- blk_update_request(tio->orig, 0, nr_bytes);
-}
-
-static struct dm_rq_target_io *tio_from_request(struct request *rq)
-{
- return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special);
-}
-
-static void rq_end_stats(struct mapped_device *md, struct request *orig)
-{
- if (unlikely(dm_stats_used(&md->stats))) {
- struct dm_rq_target_io *tio = tio_from_request(orig);
- tio->duration_jiffies = jiffies - tio->duration_jiffies;
- dm_stats_account_io(&md->stats, rq_data_dir(orig),
- blk_rq_pos(orig), tio->n_sectors, true,
- tio->duration_jiffies, &tio->stats_aux);
- }
-}
-
-/*
- * Don't touch any member of the md after calling this function because
- * the md may be freed in dm_put() at the end of this function.
- * Or do dm_get() before calling this function and dm_put() later.
- */
-static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
-{
- atomic_dec(&md->pending[rw]);
-
- /* nudge anyone waiting on suspend queue */
- if (!md_in_flight(md))
- wake_up(&md->wait);
-
- /*
- * Run this off this callpath, as drivers could invoke end_io while
- * inside their request_fn (and holding the queue lock). Calling
- * back into ->request_fn() could deadlock attempting to grab the
- * queue lock again.
- */
- if (!md->queue->mq_ops && run_queue)
- blk_run_queue_async(md->queue);
-
- /*
- * dm_put() must be at the end of this function. See the comment above
- */
- dm_put(md);
-}
-
-static void free_rq_clone(struct request *clone)
-{
- struct dm_rq_target_io *tio = clone->end_io_data;
- struct mapped_device *md = tio->md;
-
- blk_rq_unprep_clone(clone);
-
- if (md->type == DM_TYPE_MQ_REQUEST_BASED)
- /* stacked on blk-mq queue(s) */
- tio->ti->type->release_clone_rq(clone);
- else if (!md->queue->mq_ops)
- /* request_fn queue stacked on request_fn queue(s) */
- free_old_clone_request(md, clone);
-
- if (!md->queue->mq_ops)
- free_old_rq_tio(tio);
-}
-
-/*
- * Complete the clone and the original request.
- * Must be called without clone's queue lock held,
- * see end_clone_request() for more details.
- */
-static void dm_end_request(struct request *clone, int error)
-{
- int rw = rq_data_dir(clone);
- struct dm_rq_target_io *tio = clone->end_io_data;
- struct mapped_device *md = tio->md;
- struct request *rq = tio->orig;
-
- if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
- rq->errors = clone->errors;
- rq->resid_len = clone->resid_len;
-
- if (rq->sense)
- /*
- * We are using the sense buffer of the original
- * request.
- * So setting the length of the sense data is enough.
- */
- rq->sense_len = clone->sense_len;
- }
-
- free_rq_clone(clone);
- rq_end_stats(md, rq);
- if (!rq->q->mq_ops)
- blk_end_request_all(rq, error);
- else
- blk_mq_end_request(rq, error);
- rq_completed(md, rw, true);
-}
-
-static void dm_unprep_request(struct request *rq)
-{
- struct dm_rq_target_io *tio = tio_from_request(rq);
- struct request *clone = tio->clone;
-
- if (!rq->q->mq_ops) {
- rq->special = NULL;
- rq->cmd_flags &= ~REQ_DONTPREP;
- }
-
- if (clone)
- free_rq_clone(clone);
- else if (!tio->md->queue->mq_ops)
- free_old_rq_tio(tio);
-}
-
-/*
- * Requeue the original request of a clone.
- */
-static void dm_old_requeue_request(struct request *rq)
-{
- struct request_queue *q = rq->q;
- unsigned long flags;
-
- spin_lock_irqsave(q->queue_lock, flags);
- blk_requeue_request(q, rq);
- blk_run_queue_async(q);
- spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
-static void dm_mq_requeue_request(struct request *rq)
-{
- struct request_queue *q = rq->q;
- unsigned long flags;
-
- blk_mq_requeue_request(rq);
- spin_lock_irqsave(q->queue_lock, flags);
- if (!blk_queue_stopped(q))
- blk_mq_kick_requeue_list(q);
- spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
-static void dm_requeue_original_request(struct mapped_device *md,
- struct request *rq)
-{
- int rw = rq_data_dir(rq);
-
- rq_end_stats(md, rq);
- dm_unprep_request(rq);
-
- if (!rq->q->mq_ops)
- dm_old_requeue_request(rq);
- else
- dm_mq_requeue_request(rq);
-
- rq_completed(md, rw, false);
-}
-
-static void dm_old_stop_queue(struct request_queue *q)
-{
- unsigned long flags;
-
- spin_lock_irqsave(q->queue_lock, flags);
- if (blk_queue_stopped(q)) {
- spin_unlock_irqrestore(q->queue_lock, flags);
- return;
- }
-
- blk_stop_queue(q);
- spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
-static void dm_stop_queue(struct request_queue *q)
-{
- if (!q->mq_ops)
- dm_old_stop_queue(q);
- else
- blk_mq_stop_hw_queues(q);
-}
-
-static void dm_old_start_queue(struct request_queue *q)
-{
- unsigned long flags;
-
- spin_lock_irqsave(q->queue_lock, flags);
- if (blk_queue_stopped(q))
- blk_start_queue(q);
- spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
-static void dm_start_queue(struct request_queue *q)
-{
- if (!q->mq_ops)
- dm_old_start_queue(q);
- else {
- blk_mq_start_stopped_hw_queues(q, true);
- blk_mq_kick_requeue_list(q);
- }
-}
-
-static void dm_done(struct request *clone, int error, bool mapped)
-{
- int r = error;
- struct dm_rq_target_io *tio = clone->end_io_data;
- dm_request_endio_fn rq_end_io = NULL;
-
- if (tio->ti) {
- rq_end_io = tio->ti->type->rq_end_io;
-
- if (mapped && rq_end_io)
- r = rq_end_io(tio->ti, clone, error, &tio->info);
- }
-
- if (unlikely(r == -EREMOTEIO && (req_op(clone) == REQ_OP_WRITE_SAME) &&
- !clone->q->limits.max_write_same_sectors))
- disable_write_same(tio->md);
-
- if (r <= 0)
- /* The target wants to complete the I/O */
- dm_end_request(clone, r);
- else if (r == DM_ENDIO_INCOMPLETE)
- /* The target will handle the I/O */
- return;
- else if (r == DM_ENDIO_REQUEUE)
- /* The target wants to requeue the I/O */
- dm_requeue_original_request(tio->md, tio->orig);
- else {
- DMWARN("unimplemented target endio return value: %d", r);
- BUG();
- }
-}
-
-/*
- * Request completion handler for request-based dm
- */
-static void dm_softirq_done(struct request *rq)
-{
- bool mapped = true;
- struct dm_rq_target_io *tio = tio_from_request(rq);
- struct request *clone = tio->clone;
- int rw;
-
- if (!clone) {
- rq_end_stats(tio->md, rq);
- rw = rq_data_dir(rq);
- if (!rq->q->mq_ops) {
- blk_end_request_all(rq, tio->error);
- rq_completed(tio->md, rw, false);
- free_old_rq_tio(tio);
- } else {
- blk_mq_end_request(rq, tio->error);
- rq_completed(tio->md, rw, false);
- }
- return;
- }
-
- if (rq->cmd_flags & REQ_FAILED)
- mapped = false;
-
- dm_done(clone, tio->error, mapped);
-}
-
-/*
- * Complete the clone and the original request with the error status
- * through softirq context.
- */
-static void dm_complete_request(struct request *rq, int error)
-{
- struct dm_rq_target_io *tio = tio_from_request(rq);
-
- tio->error = error;
- if (!rq->q->mq_ops)
- blk_complete_request(rq);
- else
- blk_mq_complete_request(rq, error);
-}
-
-/*
- * Complete the not-mapped clone and the original request with the error status
- * through softirq context.
- * Target's rq_end_io() function isn't called.
- * This may be used when the target's map_rq() or clone_and_map_rq() functions fail.
- */
-static void dm_kill_unmapped_request(struct request *rq, int error)
-{
- rq->cmd_flags |= REQ_FAILED;
- dm_complete_request(rq, error);
-}
-
-/*
- * Called with the clone's queue lock held (in the case of .request_fn)
- */
-static void end_clone_request(struct request *clone, int error)
-{
- struct dm_rq_target_io *tio = clone->end_io_data;
-
- if (!clone->q->mq_ops) {
- /*
- * For just cleaning up the information of the queue in which
- * the clone was dispatched.
- * The clone is *NOT* freed actually here because it is alloced
- * from dm own mempool (REQ_ALLOCED isn't set).
- */
- __blk_put_request(clone->q, clone);
- }
-
- /*
- * Actual request completion is done in a softirq context which doesn't
- * hold the clone's queue lock. Otherwise, deadlock could occur because:
- * - another request may be submitted by the upper level driver
- * of the stacking during the completion
- * - the submission which requires queue lock may be done
- * against this clone's queue
- */
- dm_complete_request(tio->orig, error);
-}
-
/*
* Return maximum size of I/O possible at the supplied sector up to the current
* target boundary.
return BLK_QC_T_NONE;
}
-int dm_request_based(struct mapped_device *md)
-{
- return blk_queue_stackable(md->queue);
-}
-
-static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
-{
- int r;
-
- if (blk_queue_io_stat(clone->q))
- clone->cmd_flags |= REQ_IO_STAT;
-
- clone->start_time = jiffies;
- r = blk_insert_cloned_request(clone->q, clone);
- if (r)
- /* must complete clone in terms of original request */
- dm_complete_request(rq, r);
-}
-
-static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
- void *data)
-{
- struct dm_rq_target_io *tio = data;
- struct dm_rq_clone_bio_info *info =
- container_of(bio, struct dm_rq_clone_bio_info, clone);
-
- info->orig = bio_orig;
- info->tio = tio;
- bio->bi_end_io = end_clone_bio;
-
- return 0;
-}
-
-static int setup_clone(struct request *clone, struct request *rq,
- struct dm_rq_target_io *tio, gfp_t gfp_mask)
-{
- int r;
-
- r = blk_rq_prep_clone(clone, rq, tio->md->bs, gfp_mask,
- dm_rq_bio_constructor, tio);
- if (r)
- return r;
-
- clone->cmd = rq->cmd;
- clone->cmd_len = rq->cmd_len;
- clone->sense = rq->sense;
- clone->end_io = end_clone_request;
- clone->end_io_data = tio;
-
- tio->clone = clone;
-
- return 0;
-}
-
-static struct request *clone_old_rq(struct request *rq, struct mapped_device *md,
- struct dm_rq_target_io *tio, gfp_t gfp_mask)
-{
- /*
- * Create clone for use with .request_fn request_queue
- */
- struct request *clone;
-
- clone = alloc_old_clone_request(md, gfp_mask);
- if (!clone)
- return NULL;
-
- blk_rq_init(NULL, clone);
- if (setup_clone(clone, rq, tio, gfp_mask)) {
- /* -ENOMEM */
- free_old_clone_request(md, clone);
- return NULL;
- }
-
- return clone;
-}
-
-static void map_tio_request(struct kthread_work *work);
-
-static void init_tio(struct dm_rq_target_io *tio, struct request *rq,
- struct mapped_device *md)
-{
- tio->md = md;
- tio->ti = NULL;
- tio->clone = NULL;
- tio->orig = rq;
- tio->error = 0;
- /*
- * Avoid initializing info for blk-mq; it passes
- * target-specific data through info.ptr
- * (see: dm_mq_init_request)
- */
- if (!md->init_tio_pdu)
- memset(&tio->info, 0, sizeof(tio->info));
- if (md->kworker_task)
- init_kthread_work(&tio->work, map_tio_request);
-}
-
-static struct dm_rq_target_io *dm_old_prep_tio(struct request *rq,
- struct mapped_device *md,
- gfp_t gfp_mask)
-{
- struct dm_rq_target_io *tio;
- int srcu_idx;
- struct dm_table *table;
-
- tio = alloc_old_rq_tio(md, gfp_mask);
- if (!tio)
- return NULL;
-
- init_tio(tio, rq, md);
-
- table = dm_get_live_table(md, &srcu_idx);
- /*
- * Must clone a request if this .request_fn DM device
- * is stacked on .request_fn device(s).
- */
- if (!dm_table_mq_request_based(table)) {
- if (!clone_old_rq(rq, md, tio, gfp_mask)) {
- dm_put_live_table(md, srcu_idx);
- free_old_rq_tio(tio);
- return NULL;
- }
- }
- dm_put_live_table(md, srcu_idx);
-
- return tio;
-}
-
-/*
- * Called with the queue lock held.
- */
-static int dm_old_prep_fn(struct request_queue *q, struct request *rq)
-{
- struct mapped_device *md = q->queuedata;
- struct dm_rq_target_io *tio;
-
- if (unlikely(rq->special)) {
- DMWARN("Already has something in rq->special.");
- return BLKPREP_KILL;
- }
-
- tio = dm_old_prep_tio(rq, md, GFP_ATOMIC);
- if (!tio)
- return BLKPREP_DEFER;
-
- rq->special = tio;
- rq->cmd_flags |= REQ_DONTPREP;
-
- return BLKPREP_OK;
-}
-
-/*
- * Returns:
- * 0 : the request has been processed
- * DM_MAPIO_REQUEUE : the original request needs to be requeued
- * < 0 : the request was completed due to failure
- */
-static int map_request(struct dm_rq_target_io *tio, struct request *rq,
- struct mapped_device *md)
-{
- int r;
- struct dm_target *ti = tio->ti;
- struct request *clone = NULL;
-
- if (tio->clone) {
- clone = tio->clone;
- r = ti->type->map_rq(ti, clone, &tio->info);
- } else {
- r = ti->type->clone_and_map_rq(ti, rq, &tio->info, &clone);
- if (r < 0) {
- /* The target wants to complete the I/O */
- dm_kill_unmapped_request(rq, r);
- return r;
- }
- if (r != DM_MAPIO_REMAPPED)
- return r;
- if (setup_clone(clone, rq, tio, GFP_ATOMIC)) {
- /* -ENOMEM */
- ti->type->release_clone_rq(clone);
- return DM_MAPIO_REQUEUE;
- }
- }
-
- switch (r) {
- case DM_MAPIO_SUBMITTED:
- /* The target has taken the I/O to submit by itself later */
- break;
- case DM_MAPIO_REMAPPED:
- /* The target has remapped the I/O so dispatch it */
- trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
- blk_rq_pos(rq));
- dm_dispatch_clone_request(clone, rq);
- break;
- case DM_MAPIO_REQUEUE:
- /* The target wants to requeue the I/O */
- dm_requeue_original_request(md, tio->orig);
- break;
- default:
- if (r > 0) {
- DMWARN("unimplemented target map return value: %d", r);
- BUG();
- }
-
- /* The target wants to complete the I/O */
- dm_kill_unmapped_request(rq, r);
- return r;
- }
-
- return 0;
-}
-
-static void map_tio_request(struct kthread_work *work)
-{
- struct dm_rq_target_io *tio = container_of(work, struct dm_rq_target_io, work);
- struct request *rq = tio->orig;
- struct mapped_device *md = tio->md;
-
- if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE)
- dm_requeue_original_request(md, rq);
-}
-
-static void dm_start_request(struct mapped_device *md, struct request *orig)
-{
- if (!orig->q->mq_ops)
- blk_start_request(orig);
- else
- blk_mq_start_request(orig);
- atomic_inc(&md->pending[rq_data_dir(orig)]);
-
- if (md->seq_rq_merge_deadline_usecs) {
- md->last_rq_pos = rq_end_sector(orig);
- md->last_rq_rw = rq_data_dir(orig);
- md->last_rq_start_time = ktime_get();
- }
-
- if (unlikely(dm_stats_used(&md->stats))) {
- struct dm_rq_target_io *tio = tio_from_request(orig);
- tio->duration_jiffies = jiffies;
- tio->n_sectors = blk_rq_sectors(orig);
- dm_stats_account_io(&md->stats, rq_data_dir(orig),
- blk_rq_pos(orig), tio->n_sectors, false, 0,
- &tio->stats_aux);
- }
-
- /*
- * Hold the md reference here for the in-flight I/O.
- * We can't rely on the reference count by device opener,
- * because the device may be closed during the request completion
- * when all bios are completed.
- * See the comment in rq_completed() too.
- */
- dm_get(md);
-}
-
-#define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000
-
-ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
-{
- return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs);
-}
-
-ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
- const char *buf, size_t count)
-{
- unsigned deadline;
-
- if (!dm_request_based(md) || md->use_blk_mq)
- return count;
-
- if (kstrtouint(buf, 10, &deadline))
- return -EINVAL;
-
- if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS)
- deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS;
-
- md->seq_rq_merge_deadline_usecs = deadline;
-
- return count;
-}
-
-static bool dm_request_peeked_before_merge_deadline(struct mapped_device *md)
-{
- ktime_t kt_deadline;
-
- if (!md->seq_rq_merge_deadline_usecs)
- return false;
-
- kt_deadline = ns_to_ktime((u64)md->seq_rq_merge_deadline_usecs * NSEC_PER_USEC);
- kt_deadline = ktime_add_safe(md->last_rq_start_time, kt_deadline);
-
- return !ktime_after(ktime_get(), kt_deadline);
-}
-
-/*
- * q->request_fn for request-based dm.
- * Called with the queue lock held.
- */
-static void dm_request_fn(struct request_queue *q)
-{
- struct mapped_device *md = q->queuedata;
- struct dm_target *ti = md->immutable_target;
- struct request *rq;
- struct dm_rq_target_io *tio;
- sector_t pos = 0;
-
- if (unlikely(!ti)) {
- int srcu_idx;
- struct dm_table *map = dm_get_live_table(md, &srcu_idx);
-
- ti = dm_table_find_target(map, pos);
- dm_put_live_table(md, srcu_idx);
- }
-
- /*
- * For suspend, check blk_queue_stopped() and increment
- * ->pending within a single queue_lock not to increment the
- * number of in-flight I/Os after the queue is stopped in
- * dm_suspend().
- */
- while (!blk_queue_stopped(q)) {
- rq = blk_peek_request(q);
- if (!rq)
- return;
-
- /* always use block 0 to find the target for flushes for now */
- pos = 0;
- if (req_op(rq) != REQ_OP_FLUSH)
- pos = blk_rq_pos(rq);
-
- if ((dm_request_peeked_before_merge_deadline(md) &&
- md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
- md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
- (ti->type->busy && ti->type->busy(ti))) {
- blk_delay_queue(q, HZ / 100);
- return;
- }
-
- dm_start_request(md, rq);
-
- tio = tio_from_request(rq);
- /* Establish tio->ti before queuing work (map_tio_request) */
- tio->ti = ti;
- queue_kthread_work(&md->kworker, &tio->work);
- BUG_ON(!irqs_disabled());
- }
-}
-
static int dm_any_congested(void *congested_data, int bdi_bits)
{
int r = bdi_bits;
static void dm_wq_work(struct work_struct *work);
-static void dm_init_md_queue(struct mapped_device *md)
+void dm_init_md_queue(struct mapped_device *md)
{
/*
* Request-based dm devices cannot be stacked on top of bio-based dm
md->queue->backing_dev_info.congested_data = md;
}
-static void dm_init_normal_md_queue(struct mapped_device *md)
+void dm_init_normal_md_queue(struct mapped_device *md)
{
md->use_blk_mq = false;
dm_init_md_queue(md);
bdput(md->bdev);
md->bdev = NULL;
}
+
+ dm_mq_cleanup_mapped_device(md);
}
/*
goto bad_io_barrier;
md->numa_node_id = numa_node_id;
- md->use_blk_mq = use_blk_mq;
+ md->use_blk_mq = dm_use_blk_mq_default();
md->init_tio_pdu = false;
md->type = DM_TYPE_NONE;
mutex_init(&md->suspend_lock);
unlock_fs(md);
cleanup_mapped_device(md);
- if (md->tag_set) {
- blk_mq_free_tag_set(md->tag_set);
- kfree(md->tag_set);
- }
free_table_devices(&md->table_devices);
dm_stats_cleanup(&md->stats);
}
EXPORT_SYMBOL_GPL(dm_get_queue_limits);
-static void dm_old_init_rq_based_worker_thread(struct mapped_device *md)
-{
- /* Initialize the request-based DM worker thread */
- init_kthread_worker(&md->kworker);
- md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
- "kdmwork-%s", dm_device_name(md));
-}
-
-/*
- * Fully initialize a .request_fn request-based queue.
- */
-static int dm_old_init_request_queue(struct mapped_device *md)
-{
- /* Fully initialize the queue */
- if (!blk_init_allocated_queue(md->queue, dm_request_fn, NULL))
- return -EINVAL;
-
- /* disable dm_request_fn's merge heuristic by default */
- md->seq_rq_merge_deadline_usecs = 0;
-
- dm_init_normal_md_queue(md);
- blk_queue_softirq_done(md->queue, dm_softirq_done);
- blk_queue_prep_rq(md->queue, dm_old_prep_fn);
-
- dm_old_init_rq_based_worker_thread(md);
-
- elv_register_queue(md->queue);
-
- return 0;
-}
-
-static int dm_mq_init_request(void *data, struct request *rq,
- unsigned int hctx_idx, unsigned int request_idx,
- unsigned int numa_node)
-{
- struct mapped_device *md = data;
- struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
-
- /*
- * Must initialize md member of tio, otherwise it won't
- * be available in dm_mq_queue_rq.
- */
- tio->md = md;
-
- if (md->init_tio_pdu) {
- /* target-specific per-io data is immediately after the tio */
- tio->info.ptr = tio + 1;
- }
-
- return 0;
-}
-
-static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
- const struct blk_mq_queue_data *bd)
-{
- struct request *rq = bd->rq;
- struct dm_rq_target_io *tio = blk_mq_rq_to_pdu(rq);
- struct mapped_device *md = tio->md;
- struct dm_target *ti = md->immutable_target;
-
- if (unlikely(!ti)) {
- int srcu_idx;
- struct dm_table *map = dm_get_live_table(md, &srcu_idx);
-
- ti = dm_table_find_target(map, 0);
- dm_put_live_table(md, srcu_idx);
- }
-
- if (ti->type->busy && ti->type->busy(ti))
- return BLK_MQ_RQ_QUEUE_BUSY;
-
- dm_start_request(md, rq);
-
- /* Init tio using md established in .init_request */
- init_tio(tio, rq, md);
-
- /*
- * Establish tio->ti before queuing work (map_tio_request)
- * or making direct call to map_request().
- */
- tio->ti = ti;
-
- /* Direct call is fine since .queue_rq allows allocations */
- if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE) {
- /* Undo dm_start_request() before requeuing */
- rq_end_stats(md, rq);
- rq_completed(md, rq_data_dir(rq), false);
- return BLK_MQ_RQ_QUEUE_BUSY;
- }
-
- return BLK_MQ_RQ_QUEUE_OK;
-}
-
-static struct blk_mq_ops dm_mq_ops = {
- .queue_rq = dm_mq_queue_rq,
- .map_queue = blk_mq_map_queue,
- .complete = dm_softirq_done,
- .init_request = dm_mq_init_request,
-};
-
-static int dm_mq_init_request_queue(struct mapped_device *md,
- struct dm_target *immutable_tgt)
-{
- struct request_queue *q;
- int err;
-
- if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) {
- DMERR("request-based dm-mq may only be stacked on blk-mq device(s)");
- return -EINVAL;
- }
-
- md->tag_set = kzalloc_node(sizeof(struct blk_mq_tag_set), GFP_KERNEL, md->numa_node_id);
- if (!md->tag_set)
- return -ENOMEM;
-
- md->tag_set->ops = &dm_mq_ops;
- md->tag_set->queue_depth = dm_get_blk_mq_queue_depth();
- md->tag_set->numa_node = md->numa_node_id;
- md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
- md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues();
- md->tag_set->driver_data = md;
-
- md->tag_set->cmd_size = sizeof(struct dm_rq_target_io);
- if (immutable_tgt && immutable_tgt->per_io_data_size) {
- /* any target-specific per-io data is immediately after the tio */
- md->tag_set->cmd_size += immutable_tgt->per_io_data_size;
- md->init_tio_pdu = true;
- }
-
- err = blk_mq_alloc_tag_set(md->tag_set);
- if (err)
- goto out_kfree_tag_set;
-
- q = blk_mq_init_allocated_queue(md->tag_set, md->queue);
- if (IS_ERR(q)) {
- err = PTR_ERR(q);
- goto out_tag_set;
- }
- dm_init_md_queue(md);
-
- /* backfill 'mq' sysfs registration normally done in blk_register_queue */
- blk_mq_register_disk(md->disk);
-
- return 0;
-
-out_tag_set:
- blk_mq_free_tag_set(md->tag_set);
-out_kfree_tag_set:
- kfree(md->tag_set);
-
- return err;
-}
-
static unsigned filter_md_type(unsigned type, struct mapped_device *md)
{
if (type == DM_TYPE_BIO_BASED)
module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools");
-module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools");
-
-module_param(use_blk_mq, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(use_blk_mq, "Use block multiqueue for request-based DM devices");
-
-module_param(dm_mq_nr_hw_queues, uint, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(dm_mq_nr_hw_queues, "Number of hardware queues for request-based dm-mq devices");
-
-module_param(dm_mq_queue_depth, uint, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(dm_mq_queue_depth, "Queue depth for request-based dm-mq devices");
-
module_param(dm_numa_node, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations");
#include <linux/fs.h>
#include <linux/device-mapper.h>
#include <linux/list.h>
+#include <linux/moduleparam.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/hdreg.h>
/*
* sysfs interface
*/
-struct dm_kobject_holder {
- struct kobject kobj;
- struct completion completion;
-};
-
-static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
-{
- return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
-}
-
int dm_sysfs_init(struct mapped_device *md);
void dm_sysfs_exit(struct mapped_device *md);
struct kobject *dm_kobject(struct mapped_device *md);
void dm_internal_suspend(struct mapped_device *md);
void dm_internal_resume(struct mapped_device *md);
-bool dm_use_blk_mq(struct mapped_device *md);
-
int dm_io_init(void);
void dm_io_exit(void);
void dm_free_md_mempools(struct dm_md_mempools *pools);
/*
- * Helpers that are used by DM core
+ * Various helpers
*/
unsigned dm_get_reserved_bio_based_ios(void);
-unsigned dm_get_reserved_rq_based_ios(void);
-
-static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen)
-{
- return !maxlen || strlen(result) + 1 >= maxlen;
-}
-
-ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf);
-ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
- const char *buf, size_t count);
#endif
projects / karo-tx-linux.git / commitdiff