Commit f7e68169 authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'dm-4.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - initially based on Jens' 'for-4.8/core' (given all the flag churn)
   and later merged with 'for-4.8/core' to pickup the QUEUE_FLAG_DAX
   commits that DM depends on to provide its DAX support

 - clean up the bio-based vs request-based DM core code by moving the
   request-based DM core code out to dm-rq.[hc]

 - reinstate bio-based support in the DM multipath target (done with the
   idea that fast storage like NVMe over Fabrics could benefit) -- while
   preserving support for request_fn and blk-mq request-based DM mpath

 - SCSI and DM multipath persistent reservation fixes that were
   coordinated with Martin Petersen.

 - the DM raid target saw the most extensive change this cycle; it now
   provides reshape and takeover support (by layering ontop of the
   corresponding MD capabilities)

 - DAX support for DM core and the linear, stripe and error targets

 - a DM thin-provisioning block discard vs allocation race fix that
   addresses potential for corruption

 - a stable fix for DM verity-fec's block calculation during decode

 - a few cleanups and fixes to DM core and various targets

* tag 'dm-4.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (73 commits)
  dm: allow bio-based table to be upgraded to bio-based with DAX support
  dm snap: add fake origin_direct_access
  dm stripe: add DAX support
  dm error: add DAX support
  dm linear: add DAX support
  dm: add infrastructure for DAX support
  dm thin: fix a race condition between discarding and provisioning a block
  dm btree: fix a bug in dm_btree_find_next_single()
  dm raid: fix random optimal_io_size for raid0
  dm raid: address checkpatch.pl complaints
  dm: call PR reserve/unreserve on each underlying device
  sd: don't use the ALL_TG_PT bit for reservations
  dm: fix second blk_delay_queue() parameter to be in msec units not jiffies
  dm raid: change logical functions to actually return bool
  dm raid: use rdev_for_each in status
  dm raid: use rs->raid_disks to avoid memory leaks on free
  dm raid: support delta_disks for raid1, fix table output
  dm raid: enhance reshape check and factor out reshape setup
  dm raid: allow resize during recovery
  dm raid: fix rs_is_recovering() to allow for lvextend
  ...
parents 3fc9d690 b5ab4a9b
......@@ -14,8 +14,12 @@ The target is named "raid" and it accepts the following parameters:
<#raid_devs> <metadata_dev0> <dev0> [.. <metadata_devN> <devN>]
<raid_type>:
raid0 RAID0 striping (no resilience)
raid1 RAID1 mirroring
raid4 RAID4 dedicated parity disk
raid4 RAID4 with dedicated last parity disk
raid5_n RAID5 with dedicated last parity disk suporting takeover
Same as raid4
-Transitory layout
raid5_la RAID5 left asymmetric
- rotating parity 0 with data continuation
raid5_ra RAID5 right asymmetric
......@@ -30,7 +34,19 @@ The target is named "raid" and it accepts the following parameters:
- rotating parity N (right-to-left) with data restart
raid6_nc RAID6 N continue
- rotating parity N (right-to-left) with data continuation
raid6_n_6 RAID6 with dedicate parity disks
- parity and Q-syndrome on the last 2 disks;
laylout for takeover from/to raid4/raid5_n
raid6_la_6 Same as "raid_la" plus dedicated last Q-syndrome disk
- layout for takeover from raid5_la from/to raid6
raid6_ra_6 Same as "raid5_ra" dedicated last Q-syndrome disk
- layout for takeover from raid5_ra from/to raid6
raid6_ls_6 Same as "raid5_ls" dedicated last Q-syndrome disk
- layout for takeover from raid5_ls from/to raid6
raid6_rs_6 Same as "raid5_rs" dedicated last Q-syndrome disk
- layout for takeover from raid5_rs from/to raid6
raid10 Various RAID10 inspired algorithms chosen by additional params
(see raid10_format and raid10_copies below)
- RAID10: Striped Mirrors (aka 'Striping on top of mirrors')
- RAID1E: Integrated Adjacent Stripe Mirroring
- RAID1E: Integrated Offset Stripe Mirroring
......@@ -116,10 +132,41 @@ The target is named "raid" and it accepts the following parameters:
Here we see layouts closely akin to 'RAID1E - Integrated
Offset Stripe Mirroring'.
[delta_disks <N>]
The delta_disks option value (-251 < N < +251) triggers
device removal (negative value) or device addition (positive
value) to any reshape supporting raid levels 4/5/6 and 10.
RAID levels 4/5/6 allow for addition of devices (metadata
and data device tupel), raid10_near and raid10_offset only
allow for device addtion. raid10_far does not support any
reshaping at all.
A minimum of devices have to be kept to enforce resilience,
which is 3 devices for raid4/5 and 4 devices for raid6.
[data_offset <sectors>]
This option value defines the offset into each data device
where the data starts. This is used to provide out-of-place
reshaping space to avoid writing over data whilst
changing the layout of stripes, hence an interruption/crash
may happen at any time without the risk of losing data.
E.g. when adding devices to an existing raid set during
forward reshaping, the out-of-place space will be allocated
at the beginning of each raid device. The kernel raid4/5/6/10
MD personalities supporting such device addition will read the data from
the existing first stripes (those with smaller number of stripes)
starting at data_offset to fill up a new stripe with the larger
number of stripes, calculate the redundancy blocks (CRC/Q-syndrome)
and write that new stripe to offset 0. Same will be applied to all
N-1 other new stripes. This out-of-place scheme is used to change
the RAID type (i.e. the allocation algorithm) as well, e.g.
changing from raid5_ls to raid5_n.
<#raid_devs>: The number of devices composing the array.
Each device consists of two entries. The first is the device
containing the metadata (if any); the second is the one containing the
data.
data. A Maximum of 64 metadata/data device entries are supported
up to target version 1.8.0.
1.9.0 supports up to 253 which is enforced by the used MD kernel runtime.
If a drive has failed or is missing at creation time, a '-' can be
given for both the metadata and data drives for a given position.
......@@ -207,7 +254,6 @@ include:
"recover"- Initiate/continue a recover process.
"check" - Initiate a check (i.e. a "scrub") of the array.
"repair" - Initiate a repair of the array.
"reshape"- Currently unsupported (-EINVAL).
Discard Support
......@@ -257,3 +303,9 @@ Version History
1.5.2 'mismatch_cnt' is zero unless [last_]sync_action is "check".
1.6.0 Add discard support (and devices_handle_discard_safely module param).
1.7.0 Add support for MD RAID0 mappings.
1.8.0 Explictely check for compatible flags in the superblock metadata
and reject to start the raid set if any are set by a newer
target version, thus avoiding data corruption on a raid set
with a reshape in progress.
1.9.0 Add support for RAID level takeover/reshape/region size
and set size reduction.
......@@ -3,7 +3,8 @@
#
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,
......
/*
* 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
......@@ -683,7 +683,7 @@ static int crypt_iv_tcw_whitening(struct crypt_config *cc,
u8 *data)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
u64 sector = cpu_to_le64((u64)dmreq->iv_sector);
__le64 sector = cpu_to_le64(dmreq->iv_sector);
u8 buf[TCW_WHITENING_SIZE];
SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
int i, r;
......@@ -722,7 +722,7 @@ static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
u64 sector = cpu_to_le64((u64)dmreq->iv_sector);
__le64 sector = cpu_to_le64(dmreq->iv_sector);
u8 *src;
int r = 0;
......
......@@ -5,7 +5,7 @@
* This file is released under the GPL.
*/
#include "dm.h"
#include "dm-core.h"
#include <linux/device-mapper.h>
......
......@@ -5,7 +5,7 @@
* This file is released under the GPL.
*/
#include "dm.h"
#include "dm-core.h"
#include <linux/module.h>
#include <linux/vmalloc.h>
......@@ -1267,6 +1267,15 @@ static int populate_table(struct dm_table *table,
return dm_table_complete(table);
}
static bool is_valid_type(unsigned cur, unsigned new)
{
if (cur == new ||
(cur == DM_TYPE_BIO_BASED && new == DM_TYPE_DAX_BIO_BASED))
return true;
return false;
}
static int table_load(struct dm_ioctl *param, size_t param_size)
{
int r;
......@@ -1309,7 +1318,7 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
DMWARN("unable to set up device queue for new table.");
goto err_unlock_md_type;
}
} else if (dm_get_md_type(md) != dm_table_get_type(t)) {
} else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
DMWARN("can't change device type after initial table load.");
r = -EINVAL;
goto err_unlock_md_type;
......@@ -1670,8 +1679,7 @@ static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
return r;
}
#define DM_PARAMS_KMALLOC 0x0001 /* Params alloced with kmalloc */
#define DM_PARAMS_VMALLOC 0x0002 /* Params alloced with vmalloc */
#define DM_PARAMS_MALLOC 0x0001 /* Params allocated with kvmalloc() */
#define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
......@@ -1679,10 +1687,8 @@ static void free_params(struct dm_ioctl *param, size_t param_size, int param_fla
if (param_flags & DM_WIPE_BUFFER)
memset(param, 0, param_size);
if (param_flags & DM_PARAMS_KMALLOC)
kfree(param);
if (param_flags & DM_PARAMS_VMALLOC)
vfree(param);
if (param_flags & DM_PARAMS_MALLOC)
kvfree(param);
}
static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
......@@ -1714,19 +1720,14 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern
* Use kmalloc() rather than vmalloc() when we can.
*/
dmi = NULL;
if (param_kernel->data_size <= KMALLOC_MAX_SIZE) {
if (param_kernel->data_size <= KMALLOC_MAX_SIZE)
dmi = kmalloc(param_kernel->data_size, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
if (dmi)
*param_flags |= DM_PARAMS_KMALLOC;
}
if (!dmi) {
unsigned noio_flag;
noio_flag = memalloc_noio_save();
dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_HIGH | __GFP_HIGHMEM, PAGE_KERNEL);
memalloc_noio_restore(noio_flag);
if (dmi)
*param_flags |= DM_PARAMS_VMALLOC;
}
if (!dmi) {
......@@ -1735,6 +1736,8 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern
return -ENOMEM;
}
*param_flags |= DM_PARAMS_MALLOC;
if (copy_from_user(dmi, user, param_kernel->data_size))
goto bad;
......
......@@ -26,7 +26,7 @@
#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
......
......@@ -141,9 +141,27 @@ static int linear_iterate_devices(struct dm_target *ti,
return fn(ti, lc->dev, lc->start, ti->len, data);
}
static long linear_direct_access(struct dm_target *ti, sector_t sector,
void __pmem **kaddr, pfn_t *pfn, long size)
{
struct linear_c *lc = ti->private;
struct block_device *bdev = lc->dev->bdev;
struct blk_dax_ctl dax = {
.sector = linear_map_sector(ti, sector),
.size = size,
};
long ret;
ret = bdev_direct_access(bdev, &dax);
*kaddr = dax.addr;
*pfn = dax.pfn;
return ret;
}
static struct target_type linear_target = {
.name = "linear",
.version = {1, 2, 1},
.version = {1, 3, 0},
.module = THIS_MODULE,
.ctr = linear_ctr,
.dtr = linear_dtr,
......@@ -151,6 +169,7 @@ static struct target_type linear_target = {
.status = linear_status,
.prepare_ioctl = linear_prepare_ioctl,
.iterate_devices = linear_iterate_devices,
.direct_access = linear_direct_access,
};
int __init dm_linear_init(void)
......
......@@ -7,7 +7,8 @@
#include <linux/device-mapper.h>
#include "dm.h"
#include "dm-rq.h"
#include "dm-bio-record.h"
#include "dm-path-selector.h"
#include "dm-uevent.h"
......@@ -89,6 +90,8 @@ struct multipath {
atomic_t pg_init_in_progress; /* Only one pg_init allowed at once */
atomic_t pg_init_count; /* Number of times pg_init called */
unsigned queue_mode;
/*
* We must use a mempool of dm_mpath_io structs so that we
* can resubmit bios on error.
......@@ -97,10 +100,13 @@ struct multipath {
struct mutex work_mutex;
struct work_struct trigger_event;
struct work_struct process_queued_bios;
struct bio_list queued_bios;
};
/*
* Context information attached to each bio we process.
* Context information attached to each io we process.
*/
struct dm_mpath_io {
struct pgpath *pgpath;
......@@ -114,6 +120,7 @@ static struct kmem_cache *_mpio_cache;
static struct workqueue_struct *kmultipathd, *kmpath_handlerd;
static void trigger_event(struct work_struct *work);
static void activate_path(struct work_struct *work);
static void process_queued_bios(struct work_struct *work);
/*-----------------------------------------------
* Multipath state flags.
......@@ -185,7 +192,7 @@ static void free_priority_group(struct priority_group *pg,
kfree(pg);
}
static struct multipath *alloc_multipath(struct dm_target *ti, bool use_blk_mq)
static struct multipath *alloc_multipath(struct dm_target *ti)
{
struct multipath *m;
......@@ -203,15 +210,7 @@ static struct multipath *alloc_multipath(struct dm_target *ti, bool use_blk_mq)
mutex_init(&m->work_mutex);
m->mpio_pool = NULL;
if (!use_blk_mq) {
unsigned min_ios = dm_get_reserved_rq_based_ios();
m->mpio_pool = mempool_create_slab_pool(min_ios, _mpio_cache);
if (!m->mpio_pool) {
kfree(m);
return NULL;
}
}
m->queue_mode = DM_TYPE_NONE;
m->ti = ti;
ti->private = m;
......@@ -220,6 +219,39 @@ static struct multipath *alloc_multipath(struct dm_target *ti, bool use_blk_mq)
return m;
}
static int alloc_multipath_stage2(struct dm_target *ti, struct multipath *m)
{
if (m->queue_mode == DM_TYPE_NONE) {
/*
* Default to request-based.
*/
if (dm_use_blk_mq(dm_table_get_md(ti->table)))
m->queue_mode = DM_TYPE_MQ_REQUEST_BASED;
else
m->queue_mode = DM_TYPE_REQUEST_BASED;
}
if (m->queue_mode == DM_TYPE_REQUEST_BASED) {
unsigned min_ios = dm_get_reserved_rq_based_ios();
m->mpio_pool = mempool_create_slab_pool(min_ios, _mpio_cache);
if (!m->mpio_pool)
return -ENOMEM;
}
else if (m->queue_mode == DM_TYPE_BIO_BASED) {
INIT_WORK(&m->process_queued_bios, process_queued_bios);
/*
* bio-based doesn't support any direct scsi_dh management;
* it just discovers if a scsi_dh is attached.
*/
set_bit(MPATHF_RETAIN_ATTACHED_HW_HANDLER, &m->flags);
}
dm_table_set_type(ti->table, m->queue_mode);
return 0;
}
static void free_multipath(struct multipath *m)
{
struct priority_group *pg, *tmp;
......@@ -272,6 +304,41 @@ static void clear_request_fn_mpio(struct multipath *m, union map_info *info)
}
}
static size_t multipath_per_bio_data_size(void)
{
return sizeof(struct dm_mpath_io) + sizeof(struct dm_bio_details);
}
static struct dm_mpath_io *get_mpio_from_bio(struct bio *bio)
{
return dm_per_bio_data(bio, multipath_per_bio_data_size());
}
static struct dm_bio_details *get_bio_details_from_bio(struct bio *bio)
{
/* dm_bio_details is immediately after the dm_mpath_io in bio's per-bio-data */
struct dm_mpath_io *mpio = get_mpio_from_bio(bio);
void *bio_details = mpio + 1;
return bio_details;
}
static void multipath_init_per_bio_data(struct bio *bio, struct dm_mpath_io **mpio_p,
struct dm_bio_details **bio_details_p)
{
struct dm_mpath_io *mpio = get_mpio_from_bio(bio);
struct dm_bio_details *bio_details = get_bio_details_from_bio(bio);
memset(mpio, 0, sizeof(*mpio));
memset(bio_details, 0, sizeof(*bio_details));
dm_bio_record(bio_details, bio);
if (mpio_p)
*mpio_p = mpio;
if (bio_details_p)
*bio_details_p = bio_details;
}
/*-----------------------------------------------
* Path selection
*-----------------------------------------------*/
......@@ -431,16 +498,26 @@ static struct pgpath *choose_pgpath(struct multipath *m, size_t nr_bytes)
* and multipath_resume() calls and we have no need to check
* for the DMF_NOFLUSH_SUSPENDING flag.
*/
static int must_push_back(struct multipath *m)
static bool __must_push_back(struct multipath *m)
{
return ((test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags) !=
test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags)) &&
dm_noflush_suspending(m->ti));
}
static bool must_push_back_rq(struct multipath *m)
{
return (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags) ||
((test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags) !=
test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags)) &&
dm_noflush_suspending(m->ti)));
__must_push_back(m));
}
static bool must_push_back_bio(struct multipath *m)
{
return __must_push_back(m);
}
/*
* Map cloned requests
* Map cloned requests (request-based multipath)
*/
static int __multipath_map(struct dm_target *ti, struct request *clone,
union map_info *map_context,
......@@ -459,7 +536,7 @@ static int __multipath_map(struct dm_target *ti, struct request *clone,
pgpath = choose_pgpath(m, nr_bytes);
if (!pgpath) {
if (!must_push_back(m))
if (!must_push_back_rq(m))
r = -EIO; /* Failed */
return r;
} else if (test_bit(MPATHF_QUEUE_IO, &m->flags) ||
......@@ -529,6 +606,108 @@ static void multipath_release_clone(struct request *clone)
blk_mq_free_request(clone);
}
/*
* Map cloned bios (bio-based multipath)
*/
static int __multipath_map_bio(struct multipath *m, struct bio *bio, struct dm_mpath_io *mpio)
{
size_t nr_bytes = bio->bi_iter.bi_size;
struct pgpath *pgpath;
unsigned long flags;
bool queue_io;
/* Do we need to select a new pgpath? */
pgpath = lockless_dereference(m->current_pgpath);
queue_io = test_bit(MPATHF_QUEUE_IO, &m->flags);
if (!pgpath || !queue_io)
pgpath = choose_pgpath(m, nr_bytes);
if ((pgpath && queue_io) ||
(!pgpath && test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags))) {
/* Queue for the daemon to resubmit */
spin_lock_irqsave(&m->lock, flags);
bio_list_add(&m->queued_bios, bio);
spin_unlock_irqrestore(&m->lock, flags);
/* PG_INIT_REQUIRED cannot be set without QUEUE_IO */
if (queue_io || test_bit(MPATHF_PG_INIT_REQUIRED, &m->flags))
pg_init_all_paths(m);
else if (!queue_io)
queue_work(kmultipathd, &m->process_queued_bios);
return DM_MAPIO_SUBMITTED;
}
if (!pgpath) {
if (!must_push_back_bio(m))
return -EIO;
return DM_MAPIO_REQUEUE;
}
mpio->pgpath = pgpath;
mpio->nr_bytes = nr_bytes;
bio->bi_error = 0;
bio->bi_bdev = pgpath->path.dev->bdev;
bio->bi_rw |= REQ_FAILFAST_TRANSPORT;
if (pgpath->pg->ps.type->start_io)
pgpath->pg->ps.type->start_io(&pgpath->pg->ps,
&pgpath->path,
nr_bytes);
return DM_MAPIO_REMAPPED;
}
static int multipath_map_bio(struct dm_target *ti, struct bio *bio)
{
struct multipath *m = ti->private;
struct dm_mpath_io *mpio = NULL;
multipath_init_per_bio_data(bio, &mpio, NULL);
return __multipath_map_bio(m, bio, mpio);
}
static void process_queued_bios_list(struct multipath *m)
{
if (m->queue_mode == DM_TYPE_BIO_BASED)
queue_work(kmultipathd, &m->process_queued_bios);
}
static void process_queued_bios(struct work_struct *work)
{
int r;
unsigned long flags;
struct bio *bio;
struct bio_list bios;
struct blk_plug plug;
struct multipath *m =
container_of(work, struct multipath, process_queued_bios);
bio_list_init(&bios);
spin_lock_irqsave(&m->lock, flags);
if (bio_list_empty(&m->queued_bios)) {
spin_unlock_irqrestore(&m->lock, flags);
return;
}
bio_list_merge(&bios, &m->queued_bios);
bio_list_init(&m->queued_bios);
spin_unlock_irqrestore(&m->lock, flags);
blk_start_plug(&plug);
while ((bio = bio_list_pop(&bios))) {
r = __multipath_map_bio(m, bio, get_mpio_from_bio(bio));
if (r < 0 || r == DM_MAPIO_REQUEUE) {
bio->bi_error = r;
bio_endio(bio);
} else if (r == DM_MAPIO_REMAPPED)
generic_make_request(bio);
}
blk_finish_plug(&plug);
}
/*
* If we run out of usable paths, should we queue I/O or error it?
*/
......@@ -557,8 +736,10 @@ static int queue_if_no_path(struct multipath *m, bool queue_if_no_path,
spin_unlock_irqrestore(&m->lock, flags);
if (!queue_if_no_path)
if (!queue_if_no_path) {
dm_table_run_md_queue_async(m->ti->table);
process_queued_bios_list(m);
}
return 0;
}
......@@ -798,6 +979,12 @@ static int parse_hw_handler(struct dm_arg_set *as, struct multipath *m)
if (!hw_argc)
return 0;
if (m->queue_mode == DM_TYPE_BIO_BASED) {
dm_consume_args(as, hw_argc);
DMERR("bio-based multipath doesn't allow hardware handler args");
return 0;
}
m->hw_handler_name = kstrdup(dm_shift_arg(as), GFP_KERNEL);
if (hw_argc > 1) {
......@@ -833,7 +1020,7 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
const char *arg_name;
static struct dm_arg _args[] = {
{0, 6, "invalid number of feature args"},
{0, 8, "invalid number of feature args"},
{1, 50, "pg_init_retries must be between 1 and 50"},
{0, 60000, "pg_init_delay_msecs must be between 0 and 60000"},
};
......@@ -873,6 +1060,24 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
continue;
}
if (!strcasecmp(arg_name, "queue_mode") &&
(argc >= 1)) {
const char *queue_mode_name = dm_shift_arg(as);
if (!strcasecmp(queue_mode_name, "bio"))
m->queue_mode = DM_TYPE_BIO_BASED;
else if (!strcasecmp(queue_mode_name, "rq"))
m->queue_mode = DM_TYPE_REQUEST_BASED;
else if (!strcasecmp(queue_mode_name, "mq"))
m->queue_mode = DM_TYPE_MQ_REQUEST_BASED;
else {
ti->error = "Unknown 'queue_mode' requested";
r = -EINVAL;
}
argc--;
continue;
}
ti->error = "Unrecognised multipath feature request";
r = -EINVAL;
} while (argc && !r);
......@@ -880,8 +1085,7 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
return r;
}
static int multipath_ctr(struct dm_target *ti, unsigned int argc,
char **argv)
static int multipath_ctr(struct dm_target *ti, unsigned argc, char **argv)
{
/* target arguments */
static struct dm_arg _args[] = {
......@@ -894,12 +1098,11 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
struct dm_arg_set as;
unsigned pg_count = 0;
unsigned next_pg_num;
bool use_blk_mq = dm_use_blk_mq(dm_table_get_md(ti->table));
as.argc = argc;
as.argv = argv;
m = alloc_multipath(ti, use_blk_mq);
m = alloc_multipath(ti);
if (!m) {
ti->error = "can't allocate multipath";
return -EINVAL;
......@@ -909,6 +1112,10 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
if (r)
goto bad;
r = alloc_multipath_stage2(ti, m);
if (r)
goto bad;
r = parse_hw_handler(&as, m);
if (r)
goto bad;
......@@ -958,7 +1165,9 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
ti->num_flush_bios = 1;
ti->num_discard_bios = 1;
ti->num_write_same_bios = 1;
if (use_blk_mq)
if (m->queue_mode == DM_TYPE_BIO_BASED)
ti->per_io_data_size = multipath_per_bio_data_size();
else if (m->queue_mode == DM_TYPE_MQ_REQUEST_BASED)
ti->per_io_data_size = sizeof(struct dm_mpath_io);
return 0;
......@@ -1083,8 +1292,10 @@ static int reinstate_path(struct pgpath *pgpath)
out:
spin_unlock_irqrestore(&m->lock, flags);
if (run_queue)
if (run_queue) {
dm_table_run_md_queue_async(m->ti->table);
process_queued_bios_list(m);
}
return r;
}
......@@ -1281,6 +1492,8 @@ static void pg_init_done(void *data, int errors)
}
clear_bit(MPATHF_QUEUE_IO, &m->flags);
process_queued_bios_list(m);
/*
* Wake up any thread waiting to suspend.
*/
......@@ -1328,7 +1541,7 @@ static int do_end_io(struct multipath *m, struct request *clone,
* 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
......@@ -1347,7 +1560,7 @@ static int do_end_io(struct multipath *m, struct request *clone,
if (!atomic_read(&m->nr_valid_paths)) {
if (!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
if (!must_push_back(m))
if (!must_push_back_rq(m))
r = -EIO;
} else {
if (error == -EBADE)
......@@ -1381,6 +1594,64 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
return r;
}
static int do_end_io_bio(struct multipath *m, struct bio *clone,
int error, struct dm_mpath_io *mpio)
{
unsigned long flags;
if (!error)
return 0; /* I/O complete */
if (noretry_error(error))
return error;
if (mpio->pgpath)
fail_path(mpio->pgpath);
if (!atomic_read(&m->nr_valid_paths)) {
if (!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
if (!must_push_back_bio(m))
return -EIO;
return DM_ENDIO_REQUEUE;
} else {
if (error == -EBADE)
return error;
}
}
/* Queue for the daemon to resubmit */
dm_bio_restore(get_bio_details_from_bio(clone), clone);
spin_lock_irqsave(&m->lock, flags);
bio_list_add(&m->queued_bios, clone);
spin_unlock_irqrestore(&m->lock, flags);
if (!test_bit(MPATHF_QUEUE_IO, &m->flags))
queue_work(kmultipathd, &m->process_queued_bios);
return DM_ENDIO_INCOMPLETE;
}
static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, int error)
{
struct multipath *m = ti->private;
struct dm_mpath_io *mpio = get_mpio_from_bio(clone);
struct pgpath *pgpath;
struct path_selector *ps;
int r;
BUG_ON(!mpio);
r = do_end_io_bio(m, clone, error, mpio);
pgpath = mpio->pgpath;
if (pgpath) {
ps = &pgpath->pg->ps;
if (ps->type->end_io)
ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
}
return r;
}
/*
* Suspend can't complete until all the I/O is processed so if
* the last path fails we must error any remaining I/O.
......@@ -1454,7 +1725,9 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
DMEMIT("%u ", test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags) +
(m->pg_init_retries > 0) * 2 +
(m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT) * 2 +
test_bit(MPATHF_RETAIN_ATTACHED_HW_HANDLER, &m->flags));
test_bit(MPATHF_RETAIN_ATTACHED_HW_HANDLER, &m->flags) +
(m->queue_mode != DM_TYPE_REQUEST_BASED) * 2);
if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags))
DMEMIT("queue_if_no_path ");
if (m->pg_init_retries)
......@@ -1463,6 +1736,16 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
DMEMIT("pg_init_delay_msecs %u ", m->pg_init_delay_msecs);
if (test_bit(MPATHF_RETAIN_ATTACHED_HW_HANDLER, &m->flags))
DMEMIT("retain_attached_hw_handler ");
if (m->queue_mode != DM_TYPE_REQUEST_BASED) {
switch(m->queue_mode) {
case DM_TYPE_BIO_BASED:
DMEMIT("queue_mode bio ");
break;
case DM_TYPE_MQ_REQUEST_BASED:
DMEMIT("queue_mode mq ");
break;
}
}
}
if (!m->hw_handler_name || type == STATUSTYPE_INFO)
......@@ -1642,6 +1925,7 @@ static int multipath_prepare_ioctl(struct dm_target *ti,
if (test_bit(MPATHF_PG_INIT_REQUIRED, &m->flags))
pg_init_all_paths(m);
dm_table_run_md_queue_async(m->ti->table);
process_queued_bios_list(m);
}
/*
......@@ -1748,7 +2032,7 @@ static int multipath_busy(struct dm_target *ti)
*---------------------------------------------------------------*/
static struct target_type multipath_target = {
.name = "multipath",
.version = {1, 11, 0},
.version = {1, 12, 0},
.features = DM_TARGET_SINGLETON | DM_TARGET_IMMUTABLE,
.module = THIS_MODULE,
.ctr = multipath_ctr,
......@@ -1757,6 +2041,8 @@ static struct target_type multipath_target = {
.clone_and_map_rq = multipath_clone_and_map,
.release_clone_rq = multipath_release_clone,
.rq_end_io = multipath_end_io,
.map = multipath_map_bio,
.end_io = multipath_end_io_bio,
.presuspend = multipath_presuspend,
.postsuspend = multipath_postsuspend,
.resume = multipath_resume,
......@@ -1771,14 +2057,14 @@ static int __init dm_multipath_init(void)
{
int r;
/* allocate a slab for the dm_ios */
/* allocate a slab for the dm_mpath_ios */
_mpio_cache = KMEM_CACHE(dm_mpath_io, 0);
if (!_mpio_cache)
return -ENOMEM;
r = dm_register_target(&multipath_target);
if (r < 0) {
DMERR("register failed %d", r);
DMERR("request-based register failed %d", r);
r = -EINVAL;
goto bad_register_target;
}
......@@ -1804,10 +2090,6 @@ static int __init dm_multipath_init(void)
goto bad_alloc_kmpath_handlerd;
}
DMINFO("version %u.%u.%u loaded",
multipath_target.version[0], multipath_target.version[1],
multipath_target.version[2]);
return 0;
bad_alloc_kmpath_handlerd:
......
This source diff could not be displayed because it is too large. You can view the blob instead.
/*
* 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);
/*
* It is possible for a clone_old_rq() allocated clone to
* get passed in -- it may not yet have a request_queue.
* This is known to occur if the error target replaces
* a multipath target that has a request_fn queue stacked
* on blk-mq queue(s).
*/
if (clone->q && clone->q->mq_ops)
/* 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_all_blk_mq_devices(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_get_md_type(md) != DM_TYPE_REQUEST_BASED)
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, 10);
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));
if (IS_ERR(md->kworker_task))
return PTR_ERR(md->kworker_task);
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_table *t)
{
struct request_queue *q;
struct dm_target *immutable_tgt;
int err;
if (!dm_table_all_blk_mq_devices(t)) {
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);
immutable_tgt = dm_table_get_immutable_target(t);
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");
/*
* 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_table *t);
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
......@@ -2302,6 +2302,13 @@ static int origin_map(struct dm_target *ti, struct bio *bio)
return do_origin(o->dev, bio);
}
static long origin_direct_access(struct dm_target *ti, sector_t sector,
void __pmem **kaddr, pfn_t *pfn, long size)
{
DMWARN("device does not support dax.");
return -EIO;
}
/*
* Set the target "max_io_len" field to the minimum of all the snapshots'
* chunk sizes.
......@@ -2361,6 +2368,7 @@ static struct target_type origin_target = {
.postsuspend = origin_postsuspend,
.status = origin_status,
.iterate_devices = origin_iterate_devices,
.direct_access = origin_direct_access,
};
static struct target_type snapshot_target = {
......
......@@ -10,7 +10,7 @@
#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"
......
......@@ -308,6 +308,29 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)
return DM_MAPIO_REMAPPED;
}
static long stripe_direct_access(struct dm_target *ti, sector_t sector,
void __pmem **kaddr, pfn_t *pfn, long size)
{
struct stripe_c *sc = ti->private;
uint32_t stripe;
struct block_device *bdev;
struct blk_dax_ctl dax = {
.size = size,
};
long ret;
stripe_map_sector(sc, sector, &stripe, &dax.sector);
dax.sector += sc->stripe[stripe].physical_start;
bdev = sc->stripe[stripe].dev->bdev;
ret = bdev_direct_access(bdev, &dax);
*kaddr = dax.addr;
*pfn = dax.pfn;
return ret;
}
/*
* Stripe status:
*
......@@ -416,7 +439,7 @@ static void stripe_io_hints(struct dm_target *ti,
static struct target_type stripe_target = {
.name = "striped",
.version = {1, 5, 1},
.version = {1, 6, 0},
.module = THIS_MODULE,
.ctr = stripe_ctr,
.dtr = stripe_dtr,
......@@ -425,6 +448,7 @@ static struct target_type stripe_target = {
.status = stripe_status,
.iterate_devices = stripe_iterate_devices,
.io_hints = stripe_io_hints,
.direct_access = stripe_direct_access,
};
int __init dm_stripe_init(void)
......
......@@ -6,7 +6,8 @@
#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;
......
......@@ -5,7 +5,7 @@
* This file is released under the GPL.
*/
#include "dm.h"
#include "dm-core.h"
#include <linux/module.h>
#include <linux/vmalloc.h>
......@@ -43,8 +43,10 @@ struct dm_table {
struct dm_target *targets;
struct target_type *immutable_target_type;
unsigned integrity_supported:1;
unsigned singleton:1;
bool integrity_supported:1;
bool singleton:1;
bool all_blk_mq:1;
/*
* Indicates the rw permissions for the new logical
......@@ -206,6 +208,7 @@ int dm_table_create(struct dm_table **result, fmode_t mode,
return -ENOMEM;
}
t->type = DM_TYPE_NONE;
t->mode = mode;
t->md = md;
*result = t;
......@@ -703,7 +706,7 @@ int dm_table_add_target(struct dm_table *t, const char *type,
dm_device_name(t->md), type);
return -EINVAL;
}
t->singleton = 1;
t->singleton = true;
}
if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
......@@ -824,22 +827,70 @@ void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
}
EXPORT_SYMBOL(dm_consume_args);
static bool __table_type_bio_based(unsigned table_type)
{
return (table_type == DM_TYPE_BIO_BASED ||
table_type == DM_TYPE_DAX_BIO_BASED);
}
static bool __table_type_request_based(unsigned table_type)
{
return (table_type == DM_TYPE_REQUEST_BASED ||
table_type == DM_TYPE_MQ_REQUEST_BASED);
}
static int dm_table_set_type(struct dm_table *t)
void dm_table_set_type(struct dm_table *t, unsigned type)
{
t->type = type;
}
EXPORT_SYMBOL_GPL(dm_table_set_type);
static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
{
struct request_queue *q = bdev_get_queue(dev->bdev);
return q && blk_queue_dax(q);
}
static bool dm_table_supports_dax(struct dm_table *t)
{
struct dm_target *ti;
unsigned i = 0;
/* Ensure that all targets support DAX. */
while (i < dm_table_get_num_targets(t)) {
ti = dm_table_get_target(t, i++);
if (!ti->type->direct_access)
return false;
if (!ti->type->iterate_devices ||
!ti->type->iterate_devices(ti, device_supports_dax, NULL))
return false;
}
return true;
}
static int dm_table_determine_type(struct dm_table *t)
{
unsigned i;
unsigned bio_based = 0, request_based = 0, hybrid = 0;
bool use_blk_mq = false;
bool verify_blk_mq = false;
struct dm_target *tgt;
struct dm_dev_internal *dd;
struct list_head *devices;
struct list_head *devices = dm_table_get_devices(t);
unsigned live_md_type = dm_get_md_type(t->md);
if (t->type != DM_TYPE_NONE) {
/* target already set the table's type */
if (t->type == DM_TYPE_BIO_BASED)
return 0;
BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
goto verify_rq_based;
}
for (i = 0; i < t->num_targets; i++) {
tgt = t->targets + i;
if (dm_target_hybrid(tgt))
......@@ -871,11 +922,27 @@ static int dm_table_set_type(struct dm_table *t)
if (bio_based) {
/* We must use this table as bio-based */
t->type = DM_TYPE_BIO_BASED;
if (dm_table_supports_dax(t) ||
(list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED))
t->type = DM_TYPE_DAX_BIO_BASED;
return 0;
}
BUG_ON(!request_based); /* No targets in this table */
if (list_empty(devices) && __table_type_request_based(live_md_type)) {
/* inherit live MD type */
t->type = live_md_type;
return 0;
}
/*
* The only way to establish DM_TYPE_MQ_REQUEST_BASED is by
* having a compatible target use dm_table_set_type.
*/
t->type = DM_TYPE_REQUEST_BASED;
verify_rq_based:
/*
* Request-based dm supports only tables that have a single target now.
* To support multiple targets, request splitting support is needed,
......@@ -888,7 +955,6 @@ static int dm_table_set_type(struct dm_table *t)
}
/* Non-request-stackable devices can't be used for request-based dm */
devices = dm_table_get_devices(t);
list_for_each_entry(dd, devices, list) {
struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);
......@@ -899,10 +965,10 @@ static int dm_table_set_type(struct dm_table *t)
}
if (q->mq_ops)
use_blk_mq = true;
verify_blk_mq = true;
}
if (use_blk_mq) {
if (verify_blk_mq) {
/* verify _all_ devices in the table are blk-mq devices */
list_for_each_entry(dd, devices, list)
if (!bdev_get_queue(dd->dm_dev->bdev)->mq_ops) {
......@@ -910,14 +976,9 @@ static int dm_table_set_type(struct dm_table *t)
" are blk-mq request-stackable");
return -EINVAL;
}
t->type = DM_TYPE_MQ_REQUEST_BASED;
} else if (list_empty(devices) && __table_type_request_based(live_md_type)) {
/* inherit live MD type */
t->type = live_md_type;
} else
t->type = DM_TYPE_REQUEST_BASED;
t->all_blk_mq = true;
}
return 0;
}
......@@ -956,14 +1017,19 @@ struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
return NULL;
}
bool dm_table_bio_based(struct dm_table *t)
{
return __table_type_bio_based(dm_table_get_type(t));
}
bool dm_table_request_based(struct dm_table *t)
{
return __table_type_request_based(dm_table_get_type(t));
}
bool dm_table_mq_request_based(struct dm_table *t)
bool dm_table_all_blk_mq_devices(struct dm_table *t)
{
return dm_table_get_type(t) == DM_TYPE_MQ_REQUEST_BASED;
return t->all_blk_mq;
}
static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
......@@ -978,7 +1044,7 @@ static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *
return -EINVAL;
}
if (type == DM_TYPE_BIO_BASED)
if (__table_type_bio_based(type))
for (i = 0; i < t->num_targets; i++) {
tgt = t->targets + i;
per_io_data_size = max(per_io_data_size, tgt->per_io_data_size);
......@@ -1106,7 +1172,7 @@ static int dm_table_register_integrity(struct dm_table *t)
return 0;
if (!integrity_profile_exists(dm_disk(md))) {
t->integrity_supported = 1;
t->integrity_supported = true;
/*
* Register integrity profile during table load; we can do
* this because the final profile must match during resume.
......@@ -1129,7 +1195,7 @@ static int dm_table_register_integrity(struct dm_table *t)
}
/* Preserve existing integrity profile */
t->integrity_supported = 1;
t->integrity_supported = true;
return 0;
}
......@@ -1141,9 +1207,9 @@ int dm_table_complete(struct dm_table *t)
{
int r;
r = dm_table_set_type(t);
r = dm_table_determine_type(t);
if (r) {
DMERR("unable to set table type");
DMERR("unable to determine table type");
return r;
}
......
......@@ -4,7 +4,7 @@
* This file is released under the GPL.
*/
#include "dm.h"
#include "dm-core.h"
#include <linux/module.h>
#include <linux/init.h>
......@@ -148,9 +148,15 @@ static void io_err_release_clone_rq(struct request *clone)
{
}
static long io_err_direct_access(struct dm_target *ti, sector_t sector,
void __pmem **kaddr, pfn_t *pfn, long size)
{
return -EIO;
}
static struct target_type error_target = {
.name = "error",
.version = {1, 4, 0},
.version = {1, 5, 0},
.features = DM_TARGET_WILDCARD,
.ctr = io_err_ctr,
.dtr = io_err_dtr,
......@@ -158,6 +164,7 @@ static struct target_type error_target = {
.map_rq = io_err_map_rq,
.clone_and_map_rq = io_err_clone_and_map_rq,
.release_clone_rq = io_err_release_clone_rq,
.direct_access = io_err_direct_access,
};
int __init dm_target_init(void)
......
......@@ -1677,6 +1677,36 @@ int dm_pool_block_is_used(struct dm_pool_metadata *pmd, dm_block_t b, bool *resu
return r;
}
int dm_pool_inc_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e)
{
int r = 0;
down_write(&pmd->root_lock);
for (; b != e; b++) {
r = dm_sm_inc_block(pmd->data_sm, b);
if (r)
break;
}
up_write(&pmd->root_lock);
return r;
}
int dm_pool_dec_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e)
{
int r = 0;
down_write(&pmd->root_lock);
for (; b != e; b++) {
r = dm_sm_dec_block(pmd->data_sm, b);
if (r)
break;
}
up_write(&pmd->root_lock);
return r;
}
bool dm_thin_changed_this_transaction(struct dm_thin_device *td)
{
int r;
......
......@@ -197,6 +197,9 @@ int dm_pool_get_data_dev_size(struct dm_pool_metadata *pmd, dm_block_t *result);
int dm_pool_block_is_used(struct dm_pool_metadata *pmd, dm_block_t b, bool *result);
int dm_pool_inc_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e);
int dm_pool_dec_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e);
/*
* Returns -ENOSPC if the new size is too small and already allocated
* blocks would be lost.
......
......@@ -253,6 +253,7 @@ struct pool {
struct bio_list deferred_flush_bios;
struct list_head prepared_mappings;
struct list_head prepared_discards;
struct list_head prepared_discards_pt2;
struct list_head active_thins;
struct dm_deferred_set *shared_read_ds;
......@@ -269,6 +270,7 @@ struct pool {
process_mapping_fn process_prepared_mapping;
process_mapping_fn process_prepared_discard;
process_mapping_fn process_prepared_discard_pt2;
struct dm_bio_prison_cell **cell_sort_array;
};
......@@ -1001,7 +1003,8 @@ static void process_prepared_discard_no_passdown(struct dm_thin_new_mapping *m)
/*----------------------------------------------------------------*/
static void passdown_double_checking_shared_status(struct dm_thin_new_mapping *m)
static void passdown_double_checking_shared_status(struct dm_thin_new_mapping *m,
struct bio *discard_parent)
{
/*
* We've already unmapped this range of blocks, but before we
......@@ -1014,7 +1017,7 @@ static void passdown_double_checking_shared_status(struct dm_thin_new_mapping *m
dm_block_t b = m->data_block, e, end = m->data_block + m->virt_end - m->virt_begin;
struct discard_op op;
begin_discard(&op, tc, m->bio);
begin_discard(&op, tc, discard_parent);
while (b != end) {
/* find start of unmapped run */
for (; b < end; b++) {
......@@ -1049,28 +1052,101 @@ static void passdown_double_checking_shared_status(struct dm_thin_new_mapping *m
end_discard(&op, r);
}
static void process_prepared_discard_passdown(struct dm_thin_new_mapping *m)
static void queue_passdown_pt2(struct dm_thin_new_mapping *m)
{
unsigned long flags;
struct pool *pool = m->tc->pool;
spin_lock_irqsave(&pool->lock, flags);
list_add_tail(&m->list, &pool->prepared_discards_pt2);
spin_unlock_irqrestore(&pool->lock, flags);
wake_worker(pool);
}
static void passdown_endio(struct bio *bio)
{
/*
* It doesn't matter if the passdown discard failed, we still want
* to unmap (we ignore err).
*/
queue_passdown_pt2(bio->bi_private);
}
static void process_prepared_discard_passdown_pt1(struct dm_thin_new_mapping *m)
{
int r;
struct thin_c *tc = m->tc;
struct pool *pool = tc->pool;
struct bio *discard_parent;
dm_block_t data_end = m->data_block + (m->virt_end - m->virt_begin);
/*
* Only this thread allocates blocks, so we can be sure that the
* newly unmapped blocks will not be allocated before the end of
* the function.
*/
r = dm_thin_remove_range(tc->td, m->virt_begin, m->virt_end);
if (r) {
metadata_operation_failed(pool, "dm_thin_remove_range", r);
bio_io_error(m->bio);
cell_defer_no_holder(tc, m->cell);
mempool_free(m, pool->mapping_pool);
return;
}
} else if (m->maybe_shared) {
passdown_double_checking_shared_status(m);
discard_parent = bio_alloc(GFP_NOIO, 1);
if (!discard_parent) {
DMWARN("%s: unable to allocate top level discard bio for passdown. Skipping passdown.",
dm_device_name(tc->pool->pool_md));
queue_passdown_pt2(m);
} else {
struct discard_op op;
begin_discard(&op, tc, m->bio);
r = issue_discard(&op, m->data_block,
m->data_block + (m->virt_end - m->virt_begin));
end_discard(&op, r);
discard_parent->bi_end_io = passdown_endio;
discard_parent->bi_private = m;
if (m->maybe_shared)
passdown_double_checking_shared_status(m, discard_parent);
else {
struct discard_op op;
begin_discard(&op, tc, discard_parent);
r = issue_discard(&op, m->data_block, data_end);
end_discard(&op, r);
}
}
/*
* Increment the unmapped blocks. This prevents a race between the
* passdown io and reallocation of freed blocks.
*/
r = dm_pool_inc_data_range(pool->pmd, m->data_block, data_end);
if (r) {
metadata_operation_failed(pool, "dm_pool_inc_data_range", r);
bio_io_error(m->bio);
cell_defer_no_holder(tc, m->cell);
mempool_free(m, pool->mapping_pool);
return;
}
}
static void process_prepared_discard_passdown_pt2(struct dm_thin_new_mapping *m)
{
int r;
struct thin_c *tc = m->tc;
struct pool *pool = tc->pool;
/*
* The passdown has completed, so now we can decrement all those
* unmapped blocks.
*/
r = dm_pool_dec_data_range(pool->pmd, m->data_block,
m->data_block + (m->virt_end - m->virt_begin));
if (r) {
metadata_operation_failed(pool, "dm_pool_dec_data_range", r);
bio_io_error(m->bio);
} else
bio_endio(m->bio);
cell_defer_no_holder(tc, m->cell);
mempool_free(m, pool->mapping_pool);
}
......@@ -2215,6 +2291,8 @@ static void do_worker(struct work_struct *ws)
throttle_work_update(&pool->throttle);
process_prepared(pool, &pool->prepared_discards, &pool->process_prepared_discard);
throttle_work_update(&pool->throttle);
process_prepared(pool, &pool->prepared_discards_pt2, &pool->process_prepared_discard_pt2);
throttle_work_update(&pool->throttle);
process_deferred_bios(pool);
throttle_work_complete(&pool->throttle);
}
......@@ -2343,7 +2421,8 @@ static void set_discard_callbacks(struct pool *pool)
if (passdown_enabled(pt)) {
pool->process_discard_cell = process_discard_cell_passdown;
pool->process_prepared_discard = process_prepared_discard_passdown;
pool->process_prepared_discard = process_prepared_discard_passdown_pt1;
pool->process_prepared_discard_pt2 = process_prepared_discard_passdown_pt2;
} else {
pool->process_discard_cell = process_discard_cell_no_passdown;
pool->process_prepared_discard = process_prepared_discard_no_passdown;
......@@ -2830,6 +2909,7 @@ static struct pool *pool_create(struct mapped_device *pool_md,
bio_list_init(&pool->deferred_flush_bios);
INIT_LIST_HEAD(&pool->prepared_mappings);
INIT_LIST_HEAD(&pool->prepared_discards);
INIT_LIST_HEAD(&pool->prepared_discards_pt2);
INIT_LIST_HEAD(&pool->active_thins);
pool->low_water_triggered = false;
pool->suspended = true;
......
......@@ -453,9 +453,7 @@ int verity_fec_decode(struct dm_verity *v, struct dm_verity_io *io,
*/
offset = block << v->data_dev_block_bits;
res = offset;
div64_u64(res, v->fec->rounds << v->data_dev_block_bits);
res = div64_u64(offset, v->fec->rounds << v->data_dev_block_bits);
/*
* The base RS block we can feed to the interleaver to find out all
......
......@@ -5,13 +5,13 @@
* 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>
......@@ -20,14 +20,8 @@
#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
......@@ -63,7 +57,6 @@ static DECLARE_WORK(deferred_remove_work, do_deferred_remove);
static struct workqueue_struct *deferred_remove_workqueue;
/*
* For bio-based dm.
* One of these is allocated per bio.
*/
struct dm_io {
......@@ -76,36 +69,6 @@ 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)
/*
......@@ -120,130 +83,9 @@ struct dm_rq_clone_bio_info {
#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.
*/
......@@ -259,9 +101,6 @@ struct table_device {
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;
......@@ -269,13 +108,9 @@ 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);
......@@ -297,8 +132,8 @@ static int __dm_get_module_param_int(int *module_param, int min, int max)
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;
......@@ -319,28 +154,10 @@ static unsigned __dm_get_module_param(unsigned *module_param,
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,
......@@ -679,29 +496,7 @@ static void free_tio(struct dm_target_io *tio)
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]);
......@@ -1019,7 +814,7 @@ static void dec_pending(struct dm_io *io, int error)
}
}
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);
......@@ -1061,371 +856,6 @@ static void clone_endio(struct bio *bio)
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.
......@@ -1475,14 +905,41 @@ int dm_set_target_max_io_len(struct dm_target *ti, sector_t len)
}
EXPORT_SYMBOL_GPL(dm_set_target_max_io_len);
/*
* A target may call dm_accept_partial_bio only from the map routine. It is
* allowed for all bio types except REQ_PREFLUSH.
*
* dm_accept_partial_bio informs the dm that the target only wants to process
* additional n_sectors sectors of the bio and the rest of the data should be
* sent in a next bio.
*
static long dm_blk_direct_access(struct block_device *bdev, sector_t sector,
void __pmem **kaddr, pfn_t *pfn, long size)
{
struct mapped_device *md = bdev->bd_disk->private_data;
struct dm_table *map;
struct dm_target *ti;
int srcu_idx;
long len, ret = -EIO;
map = dm_get_live_table(md, &srcu_idx);
if (!map)
goto out;
ti = dm_table_find_target(map, sector);
if (!dm_target_is_valid(ti))
goto out;
len = max_io_len(sector, ti) << SECTOR_SHIFT;
size = min(len, size);
if (ti->type->direct_access)
ret = ti->type->direct_access(ti, sector, kaddr, pfn, size);
out:
dm_put_live_table(md, srcu_idx);
return min(ret, size);
}
/*
* A target may call dm_accept_partial_bio only from the map routine. It is
* allowed for all bio types except REQ_PREFLUSH.
*
* dm_accept_partial_bio informs the dm that the target only wants to process
* additional n_sectors sectors of the bio and the rest of the data should be
* sent in a next bio.
*
* A diagram that explains the arithmetics:
* +--------------------+---------------+-------+
* | 1 | 2 | 3 |
......@@ -1684,512 +1141,165 @@ static unsigned get_num_write_same_bios(struct dm_target *ti)
return ti->num_write_same_bios;
}
typedef bool (*is_split_required_fn)(struct dm_target *ti);
static bool is_split_required_for_discard(struct dm_target *ti)
{
return ti->split_discard_bios;
}
static int __send_changing_extent_only(struct clone_info *ci,
get_num_bios_fn get_num_bios,
is_split_required_fn is_split_required)
{
struct dm_target *ti;
unsigned len;
unsigned num_bios;
do {
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))
return -EIO;
/*
* Even though the device advertised support for this type of
* request, that does not mean every target supports it, and
* reconfiguration might also have changed that since the
* check was performed.
*/
num_bios = get_num_bios ? get_num_bios(ti) : 0;
if (!num_bios)
return -EOPNOTSUPP;
if (is_split_required && !is_split_required(ti))
len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti));
else
len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti));
__send_duplicate_bios(ci, ti, num_bios, &len);
ci->sector += len;
} while (ci->sector_count -= len);
return 0;
}
static int __send_discard(struct clone_info *ci)
{
return __send_changing_extent_only(ci, get_num_discard_bios,
is_split_required_for_discard);
}
static int __send_write_same(struct clone_info *ci)
{
return __send_changing_extent_only(ci, get_num_write_same_bios, NULL);
}
/*
* Select the correct strategy for processing a non-flush bio.
*/
static int __split_and_process_non_flush(struct clone_info *ci)
{
struct bio *bio = ci->bio;
struct dm_target *ti;
unsigned len;
int r;
if (unlikely(bio_op(bio) == REQ_OP_DISCARD))
return __send_discard(ci);
else if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME))
return __send_write_same(ci);
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))
return -EIO;
len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count);
r = __clone_and_map_data_bio(ci, ti, ci->sector, &len);
if (r < 0)
return r;
ci->sector += len;
ci->sector_count -= len;
return 0;
}
/*
* Entry point to split a bio into clones and submit them to the targets.
*/
static void __split_and_process_bio(struct mapped_device *md,
struct dm_table *map, struct bio *bio)
{
struct clone_info ci;
int error = 0;
if (unlikely(!map)) {
bio_io_error(bio);
return;
}
ci.map = map;
ci.md = md;
ci.io = alloc_io(md);
ci.io->error = 0;
atomic_set(&ci.io->io_count, 1);
ci.io->bio = bio;
ci.io->md = md;
spin_lock_init(&ci.io->endio_lock);
ci.sector = bio->bi_iter.bi_sector;
start_io_acct(ci.io);
if (bio->bi_rw & REQ_PREFLUSH) {
ci.bio = &ci.md->flush_bio;
ci.sector_count = 0;
error = __send_empty_flush(&ci);
/* dec_pending submits any data associated with flush */
} else {
ci.bio = bio;
ci.sector_count = bio_sectors(bio);
while (ci.sector_count && !error)
error = __split_and_process_non_flush(&ci);
}
/* drop the extra reference count */
dec_pending(ci.io, error);
}
/*-----------------------------------------------------------------
* CRUD END
*---------------------------------------------------------------*/
/*
* The request function that just remaps the bio built up by
* dm_merge_bvec.
*/
static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
{
int rw = bio_data_dir(bio);
struct mapped_device *md = q->queuedata;
int srcu_idx;
struct dm_table *map;
map = dm_get_live_table(md, &srcu_idx);
generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0);
/* if we're suspended, we have to queue this io for later */
if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) {
dm_put_live_table(md, srcu_idx);
if (!(bio->bi_rw & REQ_RAHEAD))
queue_io(md, bio);
else
bio_io_error(bio);
return BLK_QC_T_NONE;
}
__split_and_process_bio(md, map, bio);
dm_put_live_table(md, srcu_idx);
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;
}
typedef bool (*is_split_required_fn)(struct dm_target *ti);
return 0;
static bool is_split_required_for_discard(struct dm_target *ti)
{
return ti->split_discard_bios;
}
static void map_tio_request(struct kthread_work *work)
static int __send_changing_extent_only(struct clone_info *ci,
get_num_bios_fn get_num_bios,
is_split_required_fn is_split_required)
{
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;
struct dm_target *ti;
unsigned len;
unsigned num_bios;
if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE)
dm_requeue_original_request(md, rq);
}
do {
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))
return -EIO;
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)]);
/*
* Even though the device advertised support for this type of
* request, that does not mean every target supports it, and
* reconfiguration might also have changed that since the
* check was performed.
*/
num_bios = get_num_bios ? get_num_bios(ti) : 0;
if (!num_bios)
return -EOPNOTSUPP;
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 (is_split_required && !is_split_required(ti))
len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti));
else
len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti));
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);
}
__send_duplicate_bios(ci, ti, num_bios, &len);
/*
* 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);
ci->sector += len;
} while (ci->sector_count -= len);
return 0;
}
#define MAX_SEQ_RQ_MERGE_DEADLINE_USECS 100000
static int __send_discard(struct clone_info *ci)
{
return __send_changing_extent_only(ci, get_num_discard_bios,
is_split_required_for_discard);
}
ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf)
static int __send_write_same(struct clone_info *ci)
{
return sprintf(buf, "%u\n", md->seq_rq_merge_deadline_usecs);
return __send_changing_extent_only(ci, get_num_write_same_bios, NULL);
}
ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
const char *buf, size_t count)
/*
* Select the correct strategy for processing a non-flush bio.
*/
static int __split_and_process_non_flush(struct clone_info *ci)
{
unsigned deadline;
struct bio *bio = ci->bio;
struct dm_target *ti;
unsigned len;
int r;
if (!dm_request_based(md) || md->use_blk_mq)
return count;
if (unlikely(bio_op(bio) == REQ_OP_DISCARD))
return __send_discard(ci);
else if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME))
return __send_write_same(ci);
if (kstrtouint(buf, 10, &deadline))
return -EINVAL;
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))
return -EIO;
len = min_t(sector_t, max_io_len(ci->sector, ti), ci->sector_count);
if (deadline > MAX_SEQ_RQ_MERGE_DEADLINE_USECS)
deadline = MAX_SEQ_RQ_MERGE_DEADLINE_USECS;
r = __clone_and_map_data_bio(ci, ti, ci->sector, &len);
if (r < 0)
return r;
md->seq_rq_merge_deadline_usecs = deadline;
ci->sector += len;
ci->sector_count -= len;
return count;
return 0;
}
static bool dm_request_peeked_before_merge_deadline(struct mapped_device *md)
/*
* Entry point to split a bio into clones and submit them to the targets.
*/
static void __split_and_process_bio(struct mapped_device *md,
struct dm_table *map, struct bio *bio)
{
ktime_t kt_deadline;
struct clone_info ci;
int error = 0;
if (unlikely(!map)) {
bio_io_error(bio);
return;
}
ci.map = map;
ci.md = md;
ci.io = alloc_io(md);
ci.io->error = 0;
atomic_set(&ci.io->io_count, 1);
ci.io->bio = bio;
ci.io->md = md;
spin_lock_init(&ci.io->endio_lock);
ci.sector = bio->bi_iter.bi_sector;
if (!md->seq_rq_merge_deadline_usecs)
return false;
start_io_acct(ci.io);
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);
if (bio->bi_rw & REQ_PREFLUSH) {
ci.bio = &ci.md->flush_bio;
ci.sector_count = 0;
error = __send_empty_flush(&ci);
/* dec_pending submits any data associated with flush */
} else {
ci.bio = bio;
ci.sector_count = bio_sectors(bio);
while (ci.sector_count && !error)
error = __split_and_process_non_flush(&ci);
}
return !ktime_after(ktime_get(), kt_deadline);
/* drop the extra reference count */
dec_pending(ci.io, error);
}
/*-----------------------------------------------------------------
* CRUD END
*---------------------------------------------------------------*/
/*
* q->request_fn for request-based dm.
* Called with the queue lock held.
* The request function that just remaps the bio built up by
* dm_merge_bvec.
*/
static void dm_request_fn(struct request_queue *q)
static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
{
int rw = bio_data_dir(bio);
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;
int srcu_idx;
struct dm_table *map;
/* 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);
map = dm_get_live_table(md, &srcu_idx);
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;
}
generic_start_io_acct(rw, bio_sectors(bio), &dm_disk(md)->part0);
dm_start_request(md, rq);
/* if we're suspended, we have to queue this io for later */
if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) {
dm_put_live_table(md, srcu_idx);
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());
if (!(bio->bi_rw & REQ_RAHEAD))
queue_io(md, bio);
else
bio_io_error(bio);
return BLK_QC_T_NONE;
}
__split_and_process_bio(md, map, bio);
dm_put_live_table(md, srcu_idx);
return BLK_QC_T_NONE;
}
static int dm_any_congested(void *congested_data, int bdi_bits)
......@@ -2269,7 +1379,7 @@ static const struct block_device_operations dm_blk_dops;
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
......@@ -2290,7 +1400,7 @@ static void dm_init_md_queue(struct mapped_device *md)
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);
......@@ -2330,6 +1440,8 @@ static void cleanup_mapped_device(struct mapped_device *md)
bdput(md->bdev);
md->bdev = NULL;
}
dm_mq_cleanup_mapped_device(md);
}
/*
......@@ -2363,7 +1475,7 @@ static struct mapped_device *alloc_dev(int minor)
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);
......@@ -2448,10 +1560,6 @@ static void free_dev(struct mapped_device *md)
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);
......@@ -2467,7 +1575,7 @@ static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
if (md->bs) {
/* The md already has necessary mempools. */
if (dm_table_get_type(t) == DM_TYPE_BIO_BASED) {
if (dm_table_bio_based(t)) {
/*
* Reload bioset because front_pad may have changed
* because a different table was loaded.
......@@ -2657,176 +1765,15 @@ struct queue_limits *dm_get_queue_limits(struct mapped_device *md)
}
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)
return type;
return !md->use_blk_mq ? DM_TYPE_REQUEST_BASED : DM_TYPE_MQ_REQUEST_BASED;
}
/*
* Setup the DM device's queue based on md's type
*/
int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
{
int r;
unsigned md_type = filter_md_type(dm_get_md_type(md), md);
unsigned type = dm_get_md_type(md);
switch (md_type) {
switch (type) {
case DM_TYPE_REQUEST_BASED:
r = dm_old_init_request_queue(md);
if (r) {
......@@ -2835,13 +1782,14 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
}
break;
case DM_TYPE_MQ_REQUEST_BASED:
r = dm_mq_init_request_queue(md, dm_table_get_immutable_target(t));
r = dm_mq_init_request_queue(md, t);
if (r) {
DMERR("Cannot initialize queue for request-based dm-mq mapped device");
return r;
}
break;
case DM_TYPE_BIO_BASED:
case DM_TYPE_DAX_BIO_BASED:
dm_init_normal_md_queue(md);
blk_queue_make_request(md->queue, dm_make_request);
/*
......@@ -2850,6 +1798,9 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
*/
bioset_free(md->queue->bio_split);
md->queue->bio_split = NULL;
if (type == DM_TYPE_DAX_BIO_BASED)
queue_flag_set_unlocked(QUEUE_FLAG_DAX, md->queue);
break;
}
......@@ -3544,10 +2495,9 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, unsigned t
if (!pools)
return NULL;
type = filter_md_type(type, md);
switch (type) {
case DM_TYPE_BIO_BASED:
case DM_TYPE_DAX_BIO_BASED:
cachep = _io_cache;
pool_size = dm_get_reserved_bio_based_ios();
front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
......@@ -3604,26 +2554,76 @@ void dm_free_md_mempools(struct dm_md_mempools *pools)
kfree(pools);
}
static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
u32 flags)
struct dm_pr {
u64 old_key;
u64 new_key;
u32 flags;
bool fail_early;
};
static int dm_call_pr(struct block_device *bdev, iterate_devices_callout_fn fn,
void *data)
{
struct mapped_device *md = bdev->bd_disk->private_data;
const struct pr_ops *ops;
fmode_t mode;
int r;
struct dm_table *table;
struct dm_target *ti;
int ret = -ENOTTY, srcu_idx;
r = dm_grab_bdev_for_ioctl(md, &bdev, &mode);
if (r < 0)
return r;
table = dm_get_live_table(md, &srcu_idx);
if (!table || !dm_table_get_size(table))
goto out;
ops = bdev->bd_disk->fops->pr_ops;
if (ops && ops->pr_register)
r = ops->pr_register(bdev, old_key, new_key, flags);
else
r = -EOPNOTSUPP;
/* We only support devices that have a single target */
if (dm_table_get_num_targets(table) != 1)
goto out;
ti = dm_table_get_target(table, 0);
bdput(bdev);
return r;
ret = -EINVAL;
if (!ti->type->iterate_devices)
goto out;
ret = ti->type->iterate_devices(ti, fn, data);
out:
dm_put_live_table(md, srcu_idx);
return ret;
}
/*
* For register / unregister we need to manually call out to every path.
*/
static int __dm_pr_register(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
{
struct dm_pr *pr = data;
const struct pr_ops *ops = dev->bdev->bd_disk->fops->pr_ops;
if (!ops || !ops->pr_register)
return -EOPNOTSUPP;
return ops->pr_register(dev->bdev, pr->old_key, pr->new_key, pr->flags);
}
static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
u32 flags)
{
struct dm_pr pr = {
.old_key = old_key,
.new_key = new_key,
.flags = flags,
.fail_early = true,
};
int ret;
ret = dm_call_pr(bdev, __dm_pr_register, &pr);
if (ret && new_key) {
/* unregister all paths if we failed to register any path */
pr.old_key = new_key;
pr.new_key = 0;
pr.flags = 0;
pr.fail_early = false;
dm_call_pr(bdev, __dm_pr_register, &pr);
}
return ret;
}
static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
......@@ -3724,6 +2724,7 @@ static const struct block_device_operations dm_blk_dops = {
.open = dm_blk_open,
.release = dm_blk_close,
.ioctl = dm_blk_ioctl,
.direct_access = dm_blk_direct_access,
.getgeo = dm_blk_getgeo,
.pr_ops = &dm_pr_ops,
.owner = THIS_MODULE
......@@ -3741,18 +2742,6 @@ MODULE_PARM_DESC(major, "The major number of the device mapper");
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");
......
......@@ -13,6 +13,7 @@
#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>
......@@ -32,14 +33,6 @@
*/
#define DM_STATUS_NOFLUSH_FLAG (1 << 0)
/*
* Type of table and mapped_device's mempool
*/
#define DM_TYPE_NONE 0
#define DM_TYPE_BIO_BASED 1
#define DM_TYPE_REQUEST_BASED 2
#define DM_TYPE_MQ_REQUEST_BASED 3
/*
* List of devices that a metadevice uses and should open/close.
*/
......@@ -75,8 +68,9 @@ unsigned dm_table_get_type(struct dm_table *t);
struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
struct dm_target *dm_table_get_immutable_target(struct dm_table *t);
struct dm_target *dm_table_get_wildcard_target(struct dm_table *t);
bool dm_table_bio_based(struct dm_table *t);
bool dm_table_request_based(struct dm_table *t);
bool dm_table_mq_request_based(struct dm_table *t);
bool dm_table_all_blk_mq_devices(struct dm_table *t);
void dm_table_free_md_mempools(struct dm_table *t);
struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
......@@ -161,16 +155,6 @@ void dm_interface_exit(void);
/*
* 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);
......@@ -212,8 +196,6 @@ int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
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);
......@@ -228,18 +210,8 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, unsigned t
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
......@@ -429,7 +429,14 @@ static int dm_btree_lookup_next_single(struct dm_btree_info *info, dm_block_t ro
if (flags & INTERNAL_NODE) {
i = lower_bound(n, key);
if (i < 0 || i >= nr_entries) {
if (i < 0) {
/*
* avoid early -ENODATA return when all entries are
* higher than the search @key.
*/
i = 0;
}
if (i >= nr_entries) {
r = -ENODATA;
goto out;
}
......
......@@ -1619,8 +1619,7 @@ static int sd_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
return -EOPNOTSUPP;
return sd_pr_command(bdev, (flags & PR_FL_IGNORE_KEY) ? 0x06 : 0x00,
old_key, new_key, 0,
(1 << 0) /* APTPL */ |
(1 << 2) /* ALL_TG_PT */);
(1 << 0) /* APTPL */);
}
static int sd_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
......
......@@ -19,6 +19,15 @@ struct dm_table;
struct mapped_device;
struct bio_vec;
/*
* Type of table, mapped_device's mempool and request_queue
*/
#define DM_TYPE_NONE 0
#define DM_TYPE_BIO_BASED 1
#define DM_TYPE_REQUEST_BASED 2
#define DM_TYPE_MQ_REQUEST_BASED 3
#define DM_TYPE_DAX_BIO_BASED 4
typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
union map_info {
......@@ -116,6 +125,14 @@ typedef void (*dm_io_hints_fn) (struct dm_target *ti,
*/
typedef int (*dm_busy_fn) (struct dm_target *ti);
/*
* Returns:
* < 0 : error
* >= 0 : the number of bytes accessible at the address
*/
typedef long (*dm_direct_access_fn) (struct dm_target *ti, sector_t sector,
void __pmem **kaddr, pfn_t *pfn, long size);
void dm_error(const char *message);
struct dm_dev {
......@@ -162,6 +179,7 @@ struct target_type {
dm_busy_fn busy;
dm_iterate_devices_fn iterate_devices;
dm_io_hints_fn io_hints;
dm_direct_access_fn direct_access;
/* For internal device-mapper use. */
struct list_head list;
......@@ -443,6 +461,14 @@ int dm_table_add_target(struct dm_table *t, const char *type,
*/
void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb);
/*
* Target can use this to set the table's type.
* Can only ever be called from a target's ctr.
* Useful for "hybrid" target (supports both bio-based
* and request-based).
*/
void dm_table_set_type(struct dm_table *t, unsigned type);
/*
* Finally call this to make the table ready for use.
*/
......
......@@ -267,9 +267,9 @@ enum {
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
#define DM_VERSION_MINOR 34
#define DM_VERSION_MINOR 35
#define DM_VERSION_PATCHLEVEL 0
#define DM_VERSION_EXTRA "-ioctl (2015-10-28)"
#define DM_VERSION_EXTRA "-ioctl (2016-06-23)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */
......
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