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3073 lines
70 KiB
3073 lines
70 KiB
/* |
|
* Copyright (C) 2001, 2002 Sistina Software (UK) Limited. |
|
* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
|
* |
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* This file is released under the GPL. |
|
*/ |
|
|
|
#include "dm-core.h" |
|
#include "dm-rq.h" |
|
#include "dm-uevent.h" |
|
#include "dm-ima.h" |
|
|
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#include <linux/init.h> |
|
#include <linux/module.h> |
|
#include <linux/mutex.h> |
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#include <linux/sched/mm.h> |
|
#include <linux/sched/signal.h> |
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#include <linux/blkpg.h> |
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#include <linux/bio.h> |
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#include <linux/mempool.h> |
|
#include <linux/dax.h> |
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#include <linux/slab.h> |
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#include <linux/idr.h> |
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#include <linux/uio.h> |
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#include <linux/hdreg.h> |
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#include <linux/delay.h> |
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#include <linux/wait.h> |
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#include <linux/pr.h> |
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#include <linux/refcount.h> |
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#include <linux/part_stat.h> |
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#include <linux/blk-crypto.h> |
|
#include <linux/keyslot-manager.h> |
|
|
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#define DM_MSG_PREFIX "core" |
|
|
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/* |
|
* Cookies are numeric values sent with CHANGE and REMOVE |
|
* uevents while resuming, removing or renaming the device. |
|
*/ |
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#define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" |
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#define DM_COOKIE_LENGTH 24 |
|
|
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static const char *_name = DM_NAME; |
|
|
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static unsigned int major = 0; |
|
static unsigned int _major = 0; |
|
|
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static DEFINE_IDR(_minor_idr); |
|
|
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static DEFINE_SPINLOCK(_minor_lock); |
|
|
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static void do_deferred_remove(struct work_struct *w); |
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|
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static DECLARE_WORK(deferred_remove_work, do_deferred_remove); |
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|
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static struct workqueue_struct *deferred_remove_workqueue; |
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|
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atomic_t dm_global_event_nr = ATOMIC_INIT(0); |
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DECLARE_WAIT_QUEUE_HEAD(dm_global_eventq); |
|
|
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void dm_issue_global_event(void) |
|
{ |
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atomic_inc(&dm_global_event_nr); |
|
wake_up(&dm_global_eventq); |
|
} |
|
|
|
/* |
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* One of these is allocated (on-stack) per original bio. |
|
*/ |
|
struct clone_info { |
|
struct dm_table *map; |
|
struct bio *bio; |
|
struct dm_io *io; |
|
sector_t sector; |
|
unsigned sector_count; |
|
}; |
|
|
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#define DM_TARGET_IO_BIO_OFFSET (offsetof(struct dm_target_io, clone)) |
|
#define DM_IO_BIO_OFFSET \ |
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(offsetof(struct dm_target_io, clone) + offsetof(struct dm_io, tio)) |
|
|
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void *dm_per_bio_data(struct bio *bio, size_t data_size) |
|
{ |
|
struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
|
if (!tio->inside_dm_io) |
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return (char *)bio - DM_TARGET_IO_BIO_OFFSET - data_size; |
|
return (char *)bio - DM_IO_BIO_OFFSET - data_size; |
|
} |
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EXPORT_SYMBOL_GPL(dm_per_bio_data); |
|
|
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struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size) |
|
{ |
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struct dm_io *io = (struct dm_io *)((char *)data + data_size); |
|
if (io->magic == DM_IO_MAGIC) |
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return (struct bio *)((char *)io + DM_IO_BIO_OFFSET); |
|
BUG_ON(io->magic != DM_TIO_MAGIC); |
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return (struct bio *)((char *)io + DM_TARGET_IO_BIO_OFFSET); |
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} |
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EXPORT_SYMBOL_GPL(dm_bio_from_per_bio_data); |
|
|
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unsigned dm_bio_get_target_bio_nr(const struct bio *bio) |
|
{ |
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return container_of(bio, struct dm_target_io, clone)->target_bio_nr; |
|
} |
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EXPORT_SYMBOL_GPL(dm_bio_get_target_bio_nr); |
|
|
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#define MINOR_ALLOCED ((void *)-1) |
|
|
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#define DM_NUMA_NODE NUMA_NO_NODE |
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static int dm_numa_node = DM_NUMA_NODE; |
|
|
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#define DEFAULT_SWAP_BIOS (8 * 1048576 / PAGE_SIZE) |
|
static int swap_bios = DEFAULT_SWAP_BIOS; |
|
static int get_swap_bios(void) |
|
{ |
|
int latch = READ_ONCE(swap_bios); |
|
if (unlikely(latch <= 0)) |
|
latch = DEFAULT_SWAP_BIOS; |
|
return latch; |
|
} |
|
|
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/* |
|
* For mempools pre-allocation at the table loading time. |
|
*/ |
|
struct dm_md_mempools { |
|
struct bio_set bs; |
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struct bio_set io_bs; |
|
}; |
|
|
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struct table_device { |
|
struct list_head list; |
|
refcount_t count; |
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struct dm_dev dm_dev; |
|
}; |
|
|
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/* |
|
* Bio-based DM's mempools' reserved IOs set by the user. |
|
*/ |
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#define RESERVED_BIO_BASED_IOS 16 |
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static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; |
|
|
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static int __dm_get_module_param_int(int *module_param, int min, int max) |
|
{ |
|
int param = READ_ONCE(*module_param); |
|
int modified_param = 0; |
|
bool modified = true; |
|
|
|
if (param < min) |
|
modified_param = min; |
|
else if (param > max) |
|
modified_param = max; |
|
else |
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modified = false; |
|
|
|
if (modified) { |
|
(void)cmpxchg(module_param, param, modified_param); |
|
param = modified_param; |
|
} |
|
|
|
return param; |
|
} |
|
|
|
unsigned __dm_get_module_param(unsigned *module_param, |
|
unsigned def, unsigned max) |
|
{ |
|
unsigned param = READ_ONCE(*module_param); |
|
unsigned modified_param = 0; |
|
|
|
if (!param) |
|
modified_param = def; |
|
else if (param > max) |
|
modified_param = max; |
|
|
|
if (modified_param) { |
|
(void)cmpxchg(module_param, param, modified_param); |
|
param = modified_param; |
|
} |
|
|
|
return param; |
|
} |
|
|
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unsigned dm_get_reserved_bio_based_ios(void) |
|
{ |
|
return __dm_get_module_param(&reserved_bio_based_ios, |
|
RESERVED_BIO_BASED_IOS, DM_RESERVED_MAX_IOS); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); |
|
|
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static unsigned dm_get_numa_node(void) |
|
{ |
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return __dm_get_module_param_int(&dm_numa_node, |
|
DM_NUMA_NODE, num_online_nodes() - 1); |
|
} |
|
|
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static int __init local_init(void) |
|
{ |
|
int r; |
|
|
|
r = dm_uevent_init(); |
|
if (r) |
|
return r; |
|
|
|
deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); |
|
if (!deferred_remove_workqueue) { |
|
r = -ENOMEM; |
|
goto out_uevent_exit; |
|
} |
|
|
|
_major = major; |
|
r = register_blkdev(_major, _name); |
|
if (r < 0) |
|
goto out_free_workqueue; |
|
|
|
if (!_major) |
|
_major = r; |
|
|
|
return 0; |
|
|
|
out_free_workqueue: |
|
destroy_workqueue(deferred_remove_workqueue); |
|
out_uevent_exit: |
|
dm_uevent_exit(); |
|
|
|
return r; |
|
} |
|
|
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static void local_exit(void) |
|
{ |
|
flush_scheduled_work(); |
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destroy_workqueue(deferred_remove_workqueue); |
|
|
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unregister_blkdev(_major, _name); |
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dm_uevent_exit(); |
|
|
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_major = 0; |
|
|
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DMINFO("cleaned up"); |
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} |
|
|
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static int (*_inits[])(void) __initdata = { |
|
local_init, |
|
dm_target_init, |
|
dm_linear_init, |
|
dm_stripe_init, |
|
dm_io_init, |
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dm_kcopyd_init, |
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dm_interface_init, |
|
dm_statistics_init, |
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}; |
|
|
|
static void (*_exits[])(void) = { |
|
local_exit, |
|
dm_target_exit, |
|
dm_linear_exit, |
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dm_stripe_exit, |
|
dm_io_exit, |
|
dm_kcopyd_exit, |
|
dm_interface_exit, |
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dm_statistics_exit, |
|
}; |
|
|
|
static int __init dm_init(void) |
|
{ |
|
const int count = ARRAY_SIZE(_inits); |
|
int r, i; |
|
|
|
#if (IS_ENABLED(CONFIG_IMA) && !IS_ENABLED(CONFIG_IMA_DISABLE_HTABLE)) |
|
DMWARN("CONFIG_IMA_DISABLE_HTABLE is disabled." |
|
" Duplicate IMA measurements will not be recorded in the IMA log."); |
|
#endif |
|
|
|
for (i = 0; i < count; i++) { |
|
r = _inits[i](); |
|
if (r) |
|
goto bad; |
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} |
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|
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return 0; |
|
bad: |
|
while (i--) |
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_exits[i](); |
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|
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return r; |
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} |
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|
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static void __exit dm_exit(void) |
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{ |
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int i = ARRAY_SIZE(_exits); |
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|
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while (i--) |
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_exits[i](); |
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|
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/* |
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* Should be empty by this point. |
|
*/ |
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idr_destroy(&_minor_idr); |
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} |
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|
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/* |
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* Block device functions |
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*/ |
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int dm_deleting_md(struct mapped_device *md) |
|
{ |
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return test_bit(DMF_DELETING, &md->flags); |
|
} |
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|
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static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
|
{ |
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struct mapped_device *md; |
|
|
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spin_lock(&_minor_lock); |
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|
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md = bdev->bd_disk->private_data; |
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if (!md) |
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goto out; |
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|
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if (test_bit(DMF_FREEING, &md->flags) || |
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dm_deleting_md(md)) { |
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md = NULL; |
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goto out; |
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} |
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|
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dm_get(md); |
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atomic_inc(&md->open_count); |
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out: |
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spin_unlock(&_minor_lock); |
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|
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return md ? 0 : -ENXIO; |
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} |
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|
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static void dm_blk_close(struct gendisk *disk, fmode_t mode) |
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{ |
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struct mapped_device *md; |
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|
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spin_lock(&_minor_lock); |
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|
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md = disk->private_data; |
|
if (WARN_ON(!md)) |
|
goto out; |
|
|
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if (atomic_dec_and_test(&md->open_count) && |
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(test_bit(DMF_DEFERRED_REMOVE, &md->flags))) |
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queue_work(deferred_remove_workqueue, &deferred_remove_work); |
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|
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dm_put(md); |
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out: |
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spin_unlock(&_minor_lock); |
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} |
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|
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int dm_open_count(struct mapped_device *md) |
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{ |
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return atomic_read(&md->open_count); |
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} |
|
|
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/* |
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* Guarantees nothing is using the device before it's deleted. |
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*/ |
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int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) |
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{ |
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int r = 0; |
|
|
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spin_lock(&_minor_lock); |
|
|
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if (dm_open_count(md)) { |
|
r = -EBUSY; |
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if (mark_deferred) |
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set_bit(DMF_DEFERRED_REMOVE, &md->flags); |
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} else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) |
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r = -EEXIST; |
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else |
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set_bit(DMF_DELETING, &md->flags); |
|
|
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spin_unlock(&_minor_lock); |
|
|
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return r; |
|
} |
|
|
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int dm_cancel_deferred_remove(struct mapped_device *md) |
|
{ |
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int r = 0; |
|
|
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spin_lock(&_minor_lock); |
|
|
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if (test_bit(DMF_DELETING, &md->flags)) |
|
r = -EBUSY; |
|
else |
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clear_bit(DMF_DEFERRED_REMOVE, &md->flags); |
|
|
|
spin_unlock(&_minor_lock); |
|
|
|
return r; |
|
} |
|
|
|
static void do_deferred_remove(struct work_struct *w) |
|
{ |
|
dm_deferred_remove(); |
|
} |
|
|
|
static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
|
{ |
|
struct mapped_device *md = bdev->bd_disk->private_data; |
|
|
|
return dm_get_geometry(md, geo); |
|
} |
|
|
|
static int dm_prepare_ioctl(struct mapped_device *md, int *srcu_idx, |
|
struct block_device **bdev) |
|
{ |
|
struct dm_target *tgt; |
|
struct dm_table *map; |
|
int r; |
|
|
|
retry: |
|
r = -ENOTTY; |
|
map = dm_get_live_table(md, srcu_idx); |
|
if (!map || !dm_table_get_size(map)) |
|
return r; |
|
|
|
/* We only support devices that have a single target */ |
|
if (dm_table_get_num_targets(map) != 1) |
|
return r; |
|
|
|
tgt = dm_table_get_target(map, 0); |
|
if (!tgt->type->prepare_ioctl) |
|
return r; |
|
|
|
if (dm_suspended_md(md)) |
|
return -EAGAIN; |
|
|
|
r = tgt->type->prepare_ioctl(tgt, bdev); |
|
if (r == -ENOTCONN && !fatal_signal_pending(current)) { |
|
dm_put_live_table(md, *srcu_idx); |
|
msleep(10); |
|
goto retry; |
|
} |
|
|
|
return r; |
|
} |
|
|
|
static void dm_unprepare_ioctl(struct mapped_device *md, int srcu_idx) |
|
{ |
|
dm_put_live_table(md, srcu_idx); |
|
} |
|
|
|
static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
struct mapped_device *md = bdev->bd_disk->private_data; |
|
int r, srcu_idx; |
|
|
|
r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
|
if (r < 0) |
|
goto out; |
|
|
|
if (r > 0) { |
|
/* |
|
* Target determined this ioctl is being issued against a |
|
* subset of the parent bdev; require extra privileges. |
|
*/ |
|
if (!capable(CAP_SYS_RAWIO)) { |
|
DMDEBUG_LIMIT( |
|
"%s: sending ioctl %x to DM device without required privilege.", |
|
current->comm, cmd); |
|
r = -ENOIOCTLCMD; |
|
goto out; |
|
} |
|
} |
|
|
|
if (!bdev->bd_disk->fops->ioctl) |
|
r = -ENOTTY; |
|
else |
|
r = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg); |
|
out: |
|
dm_unprepare_ioctl(md, srcu_idx); |
|
return r; |
|
} |
|
|
|
u64 dm_start_time_ns_from_clone(struct bio *bio) |
|
{ |
|
struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
|
struct dm_io *io = tio->io; |
|
|
|
return jiffies_to_nsecs(io->start_time); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_start_time_ns_from_clone); |
|
|
|
static void start_io_acct(struct dm_io *io) |
|
{ |
|
struct mapped_device *md = io->md; |
|
struct bio *bio = io->orig_bio; |
|
|
|
bio_start_io_acct_time(bio, io->start_time); |
|
if (unlikely(dm_stats_used(&md->stats))) |
|
dm_stats_account_io(&md->stats, bio_data_dir(bio), |
|
bio->bi_iter.bi_sector, bio_sectors(bio), |
|
false, 0, &io->stats_aux); |
|
} |
|
|
|
static void end_io_acct(struct mapped_device *md, struct bio *bio, |
|
unsigned long start_time, struct dm_stats_aux *stats_aux) |
|
{ |
|
unsigned long duration = jiffies - start_time; |
|
|
|
bio_end_io_acct(bio, start_time); |
|
|
|
if (unlikely(dm_stats_used(&md->stats))) |
|
dm_stats_account_io(&md->stats, bio_data_dir(bio), |
|
bio->bi_iter.bi_sector, bio_sectors(bio), |
|
true, duration, stats_aux); |
|
|
|
/* nudge anyone waiting on suspend queue */ |
|
if (unlikely(wq_has_sleeper(&md->wait))) |
|
wake_up(&md->wait); |
|
} |
|
|
|
static struct dm_io *alloc_io(struct mapped_device *md, struct bio *bio) |
|
{ |
|
struct dm_io *io; |
|
struct dm_target_io *tio; |
|
struct bio *clone; |
|
|
|
clone = bio_alloc_bioset(GFP_NOIO, 0, &md->io_bs); |
|
if (!clone) |
|
return NULL; |
|
|
|
tio = container_of(clone, struct dm_target_io, clone); |
|
tio->inside_dm_io = true; |
|
tio->io = NULL; |
|
|
|
io = container_of(tio, struct dm_io, tio); |
|
io->magic = DM_IO_MAGIC; |
|
io->status = 0; |
|
atomic_set(&io->io_count, 1); |
|
io->orig_bio = bio; |
|
io->md = md; |
|
spin_lock_init(&io->endio_lock); |
|
|
|
io->start_time = jiffies; |
|
|
|
return io; |
|
} |
|
|
|
static void free_io(struct mapped_device *md, struct dm_io *io) |
|
{ |
|
bio_put(&io->tio.clone); |
|
} |
|
|
|
static struct dm_target_io *alloc_tio(struct clone_info *ci, struct dm_target *ti, |
|
unsigned target_bio_nr, gfp_t gfp_mask) |
|
{ |
|
struct dm_target_io *tio; |
|
|
|
if (!ci->io->tio.io) { |
|
/* the dm_target_io embedded in ci->io is available */ |
|
tio = &ci->io->tio; |
|
} else { |
|
struct bio *clone = bio_alloc_bioset(gfp_mask, 0, &ci->io->md->bs); |
|
if (!clone) |
|
return NULL; |
|
|
|
tio = container_of(clone, struct dm_target_io, clone); |
|
tio->inside_dm_io = false; |
|
} |
|
|
|
tio->magic = DM_TIO_MAGIC; |
|
tio->io = ci->io; |
|
tio->ti = ti; |
|
tio->target_bio_nr = target_bio_nr; |
|
|
|
return tio; |
|
} |
|
|
|
static void free_tio(struct dm_target_io *tio) |
|
{ |
|
if (tio->inside_dm_io) |
|
return; |
|
bio_put(&tio->clone); |
|
} |
|
|
|
/* |
|
* Add the bio to the list of deferred io. |
|
*/ |
|
static void queue_io(struct mapped_device *md, struct bio *bio) |
|
{ |
|
unsigned long flags; |
|
|
|
spin_lock_irqsave(&md->deferred_lock, flags); |
|
bio_list_add(&md->deferred, bio); |
|
spin_unlock_irqrestore(&md->deferred_lock, flags); |
|
queue_work(md->wq, &md->work); |
|
} |
|
|
|
/* |
|
* Everyone (including functions in this file), should use this |
|
* function to access the md->map field, and make sure they call |
|
* dm_put_live_table() when finished. |
|
*/ |
|
struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) |
|
{ |
|
*srcu_idx = srcu_read_lock(&md->io_barrier); |
|
|
|
return srcu_dereference(md->map, &md->io_barrier); |
|
} |
|
|
|
void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) |
|
{ |
|
srcu_read_unlock(&md->io_barrier, srcu_idx); |
|
} |
|
|
|
void dm_sync_table(struct mapped_device *md) |
|
{ |
|
synchronize_srcu(&md->io_barrier); |
|
synchronize_rcu_expedited(); |
|
} |
|
|
|
/* |
|
* A fast alternative to dm_get_live_table/dm_put_live_table. |
|
* The caller must not block between these two functions. |
|
*/ |
|
static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) |
|
{ |
|
rcu_read_lock(); |
|
return rcu_dereference(md->map); |
|
} |
|
|
|
static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) |
|
{ |
|
rcu_read_unlock(); |
|
} |
|
|
|
static char *_dm_claim_ptr = "I belong to device-mapper"; |
|
|
|
/* |
|
* Open a table device so we can use it as a map destination. |
|
*/ |
|
static int open_table_device(struct table_device *td, dev_t dev, |
|
struct mapped_device *md) |
|
{ |
|
struct block_device *bdev; |
|
|
|
int r; |
|
|
|
BUG_ON(td->dm_dev.bdev); |
|
|
|
bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _dm_claim_ptr); |
|
if (IS_ERR(bdev)) |
|
return PTR_ERR(bdev); |
|
|
|
r = bd_link_disk_holder(bdev, dm_disk(md)); |
|
if (r) { |
|
blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); |
|
return r; |
|
} |
|
|
|
td->dm_dev.bdev = bdev; |
|
td->dm_dev.dax_dev = fs_dax_get_by_bdev(bdev); |
|
return 0; |
|
} |
|
|
|
/* |
|
* Close a table device that we've been using. |
|
*/ |
|
static void close_table_device(struct table_device *td, struct mapped_device *md) |
|
{ |
|
if (!td->dm_dev.bdev) |
|
return; |
|
|
|
bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); |
|
blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); |
|
put_dax(td->dm_dev.dax_dev); |
|
td->dm_dev.bdev = NULL; |
|
td->dm_dev.dax_dev = NULL; |
|
} |
|
|
|
static struct table_device *find_table_device(struct list_head *l, dev_t dev, |
|
fmode_t mode) |
|
{ |
|
struct table_device *td; |
|
|
|
list_for_each_entry(td, l, list) |
|
if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) |
|
return td; |
|
|
|
return NULL; |
|
} |
|
|
|
int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, |
|
struct dm_dev **result) |
|
{ |
|
int r; |
|
struct table_device *td; |
|
|
|
mutex_lock(&md->table_devices_lock); |
|
td = find_table_device(&md->table_devices, dev, mode); |
|
if (!td) { |
|
td = kmalloc_node(sizeof(*td), GFP_KERNEL, md->numa_node_id); |
|
if (!td) { |
|
mutex_unlock(&md->table_devices_lock); |
|
return -ENOMEM; |
|
} |
|
|
|
td->dm_dev.mode = mode; |
|
td->dm_dev.bdev = NULL; |
|
|
|
if ((r = open_table_device(td, dev, md))) { |
|
mutex_unlock(&md->table_devices_lock); |
|
kfree(td); |
|
return r; |
|
} |
|
|
|
format_dev_t(td->dm_dev.name, dev); |
|
|
|
refcount_set(&td->count, 1); |
|
list_add(&td->list, &md->table_devices); |
|
} else { |
|
refcount_inc(&td->count); |
|
} |
|
mutex_unlock(&md->table_devices_lock); |
|
|
|
*result = &td->dm_dev; |
|
return 0; |
|
} |
|
|
|
void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) |
|
{ |
|
struct table_device *td = container_of(d, struct table_device, dm_dev); |
|
|
|
mutex_lock(&md->table_devices_lock); |
|
if (refcount_dec_and_test(&td->count)) { |
|
close_table_device(td, md); |
|
list_del(&td->list); |
|
kfree(td); |
|
} |
|
mutex_unlock(&md->table_devices_lock); |
|
} |
|
|
|
static void free_table_devices(struct list_head *devices) |
|
{ |
|
struct list_head *tmp, *next; |
|
|
|
list_for_each_safe(tmp, next, devices) { |
|
struct table_device *td = list_entry(tmp, struct table_device, list); |
|
|
|
DMWARN("dm_destroy: %s still exists with %d references", |
|
td->dm_dev.name, refcount_read(&td->count)); |
|
kfree(td); |
|
} |
|
} |
|
|
|
/* |
|
* Get the geometry associated with a dm device |
|
*/ |
|
int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) |
|
{ |
|
*geo = md->geometry; |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Set the geometry of a device. |
|
*/ |
|
int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) |
|
{ |
|
sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; |
|
|
|
if (geo->start > sz) { |
|
DMWARN("Start sector is beyond the geometry limits."); |
|
return -EINVAL; |
|
} |
|
|
|
md->geometry = *geo; |
|
|
|
return 0; |
|
} |
|
|
|
static int __noflush_suspending(struct mapped_device *md) |
|
{ |
|
return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
|
} |
|
|
|
/* |
|
* Decrements the number of outstanding ios that a bio has been |
|
* cloned into, completing the original io if necc. |
|
*/ |
|
void dm_io_dec_pending(struct dm_io *io, blk_status_t error) |
|
{ |
|
unsigned long flags; |
|
blk_status_t io_error; |
|
struct bio *bio; |
|
struct mapped_device *md = io->md; |
|
unsigned long start_time = 0; |
|
struct dm_stats_aux stats_aux; |
|
|
|
/* Push-back supersedes any I/O errors */ |
|
if (unlikely(error)) { |
|
spin_lock_irqsave(&io->endio_lock, flags); |
|
if (!(io->status == BLK_STS_DM_REQUEUE && __noflush_suspending(md))) |
|
io->status = error; |
|
spin_unlock_irqrestore(&io->endio_lock, flags); |
|
} |
|
|
|
if (atomic_dec_and_test(&io->io_count)) { |
|
bio = io->orig_bio; |
|
if (io->status == BLK_STS_DM_REQUEUE) { |
|
/* |
|
* Target requested pushing back the I/O. |
|
*/ |
|
spin_lock_irqsave(&md->deferred_lock, flags); |
|
if (__noflush_suspending(md) && |
|
!WARN_ON_ONCE(dm_is_zone_write(md, bio))) { |
|
/* NOTE early return due to BLK_STS_DM_REQUEUE below */ |
|
bio_list_add_head(&md->deferred, bio); |
|
} else { |
|
/* |
|
* noflush suspend was interrupted or this is |
|
* a write to a zoned target. |
|
*/ |
|
io->status = BLK_STS_IOERR; |
|
} |
|
spin_unlock_irqrestore(&md->deferred_lock, flags); |
|
} |
|
|
|
io_error = io->status; |
|
start_time = io->start_time; |
|
stats_aux = io->stats_aux; |
|
free_io(md, io); |
|
end_io_acct(md, bio, start_time, &stats_aux); |
|
|
|
if (io_error == BLK_STS_DM_REQUEUE) |
|
return; |
|
|
|
if ((bio->bi_opf & REQ_PREFLUSH) && bio->bi_iter.bi_size) { |
|
/* |
|
* Preflush done for flush with data, reissue |
|
* without REQ_PREFLUSH. |
|
*/ |
|
bio->bi_opf &= ~REQ_PREFLUSH; |
|
queue_io(md, bio); |
|
} else { |
|
/* done with normal IO or empty flush */ |
|
if (io_error) |
|
bio->bi_status = io_error; |
|
bio_endio(bio); |
|
} |
|
} |
|
} |
|
|
|
void disable_discard(struct mapped_device *md) |
|
{ |
|
struct queue_limits *limits = dm_get_queue_limits(md); |
|
|
|
/* device doesn't really support DISCARD, disable it */ |
|
limits->max_discard_sectors = 0; |
|
blk_queue_flag_clear(QUEUE_FLAG_DISCARD, md->queue); |
|
} |
|
|
|
void disable_write_same(struct mapped_device *md) |
|
{ |
|
struct queue_limits *limits = dm_get_queue_limits(md); |
|
|
|
/* device doesn't really support WRITE SAME, disable it */ |
|
limits->max_write_same_sectors = 0; |
|
} |
|
|
|
void disable_write_zeroes(struct mapped_device *md) |
|
{ |
|
struct queue_limits *limits = dm_get_queue_limits(md); |
|
|
|
/* device doesn't really support WRITE ZEROES, disable it */ |
|
limits->max_write_zeroes_sectors = 0; |
|
} |
|
|
|
static bool swap_bios_limit(struct dm_target *ti, struct bio *bio) |
|
{ |
|
return unlikely((bio->bi_opf & REQ_SWAP) != 0) && unlikely(ti->limit_swap_bios); |
|
} |
|
|
|
static void clone_endio(struct bio *bio) |
|
{ |
|
blk_status_t error = bio->bi_status; |
|
struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
|
struct dm_io *io = tio->io; |
|
struct mapped_device *md = tio->io->md; |
|
dm_endio_fn endio = tio->ti->type->end_io; |
|
struct request_queue *q = bio->bi_bdev->bd_disk->queue; |
|
|
|
if (unlikely(error == BLK_STS_TARGET)) { |
|
if (bio_op(bio) == REQ_OP_DISCARD && |
|
!q->limits.max_discard_sectors) |
|
disable_discard(md); |
|
else if (bio_op(bio) == REQ_OP_WRITE_SAME && |
|
!q->limits.max_write_same_sectors) |
|
disable_write_same(md); |
|
else if (bio_op(bio) == REQ_OP_WRITE_ZEROES && |
|
!q->limits.max_write_zeroes_sectors) |
|
disable_write_zeroes(md); |
|
} |
|
|
|
if (blk_queue_is_zoned(q)) |
|
dm_zone_endio(io, bio); |
|
|
|
if (endio) { |
|
int r = endio(tio->ti, bio, &error); |
|
switch (r) { |
|
case DM_ENDIO_REQUEUE: |
|
/* |
|
* Requeuing writes to a sequential zone of a zoned |
|
* target will break the sequential write pattern: |
|
* fail such IO. |
|
*/ |
|
if (WARN_ON_ONCE(dm_is_zone_write(md, bio))) |
|
error = BLK_STS_IOERR; |
|
else |
|
error = BLK_STS_DM_REQUEUE; |
|
fallthrough; |
|
case DM_ENDIO_DONE: |
|
break; |
|
case DM_ENDIO_INCOMPLETE: |
|
/* The target will handle the io */ |
|
return; |
|
default: |
|
DMWARN("unimplemented target endio return value: %d", r); |
|
BUG(); |
|
} |
|
} |
|
|
|
if (unlikely(swap_bios_limit(tio->ti, bio))) { |
|
struct mapped_device *md = io->md; |
|
up(&md->swap_bios_semaphore); |
|
} |
|
|
|
free_tio(tio); |
|
dm_io_dec_pending(io, error); |
|
} |
|
|
|
/* |
|
* Return maximum size of I/O possible at the supplied sector up to the current |
|
* target boundary. |
|
*/ |
|
static inline sector_t max_io_len_target_boundary(struct dm_target *ti, |
|
sector_t target_offset) |
|
{ |
|
return ti->len - target_offset; |
|
} |
|
|
|
static sector_t max_io_len(struct dm_target *ti, sector_t sector) |
|
{ |
|
sector_t target_offset = dm_target_offset(ti, sector); |
|
sector_t len = max_io_len_target_boundary(ti, target_offset); |
|
sector_t max_len; |
|
|
|
/* |
|
* Does the target need to split IO even further? |
|
* - varied (per target) IO splitting is a tenet of DM; this |
|
* explains why stacked chunk_sectors based splitting via |
|
* blk_max_size_offset() isn't possible here. So pass in |
|
* ti->max_io_len to override stacked chunk_sectors. |
|
*/ |
|
if (ti->max_io_len) { |
|
max_len = blk_max_size_offset(ti->table->md->queue, |
|
target_offset, ti->max_io_len); |
|
if (len > max_len) |
|
len = max_len; |
|
} |
|
|
|
return len; |
|
} |
|
|
|
int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) |
|
{ |
|
if (len > UINT_MAX) { |
|
DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", |
|
(unsigned long long)len, UINT_MAX); |
|
ti->error = "Maximum size of target IO is too large"; |
|
return -EINVAL; |
|
} |
|
|
|
ti->max_io_len = (uint32_t) len; |
|
|
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); |
|
|
|
static struct dm_target *dm_dax_get_live_target(struct mapped_device *md, |
|
sector_t sector, int *srcu_idx) |
|
__acquires(md->io_barrier) |
|
{ |
|
struct dm_table *map; |
|
struct dm_target *ti; |
|
|
|
map = dm_get_live_table(md, srcu_idx); |
|
if (!map) |
|
return NULL; |
|
|
|
ti = dm_table_find_target(map, sector); |
|
if (!ti) |
|
return NULL; |
|
|
|
return ti; |
|
} |
|
|
|
static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, |
|
long nr_pages, void **kaddr, pfn_t *pfn) |
|
{ |
|
struct mapped_device *md = dax_get_private(dax_dev); |
|
sector_t sector = pgoff * PAGE_SECTORS; |
|
struct dm_target *ti; |
|
long len, ret = -EIO; |
|
int srcu_idx; |
|
|
|
ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
|
|
|
if (!ti) |
|
goto out; |
|
if (!ti->type->direct_access) |
|
goto out; |
|
len = max_io_len(ti, sector) / PAGE_SECTORS; |
|
if (len < 1) |
|
goto out; |
|
nr_pages = min(len, nr_pages); |
|
ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn); |
|
|
|
out: |
|
dm_put_live_table(md, srcu_idx); |
|
|
|
return ret; |
|
} |
|
|
|
static bool dm_dax_supported(struct dax_device *dax_dev, struct block_device *bdev, |
|
int blocksize, sector_t start, sector_t len) |
|
{ |
|
struct mapped_device *md = dax_get_private(dax_dev); |
|
struct dm_table *map; |
|
bool ret = false; |
|
int srcu_idx; |
|
|
|
map = dm_get_live_table(md, &srcu_idx); |
|
if (!map) |
|
goto out; |
|
|
|
ret = dm_table_supports_dax(map, device_not_dax_capable, &blocksize); |
|
|
|
out: |
|
dm_put_live_table(md, srcu_idx); |
|
|
|
return ret; |
|
} |
|
|
|
static size_t dm_dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, |
|
void *addr, size_t bytes, struct iov_iter *i) |
|
{ |
|
struct mapped_device *md = dax_get_private(dax_dev); |
|
sector_t sector = pgoff * PAGE_SECTORS; |
|
struct dm_target *ti; |
|
long ret = 0; |
|
int srcu_idx; |
|
|
|
ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
|
|
|
if (!ti) |
|
goto out; |
|
if (!ti->type->dax_copy_from_iter) { |
|
ret = copy_from_iter(addr, bytes, i); |
|
goto out; |
|
} |
|
ret = ti->type->dax_copy_from_iter(ti, pgoff, addr, bytes, i); |
|
out: |
|
dm_put_live_table(md, srcu_idx); |
|
|
|
return ret; |
|
} |
|
|
|
static size_t dm_dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, |
|
void *addr, size_t bytes, struct iov_iter *i) |
|
{ |
|
struct mapped_device *md = dax_get_private(dax_dev); |
|
sector_t sector = pgoff * PAGE_SECTORS; |
|
struct dm_target *ti; |
|
long ret = 0; |
|
int srcu_idx; |
|
|
|
ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
|
|
|
if (!ti) |
|
goto out; |
|
if (!ti->type->dax_copy_to_iter) { |
|
ret = copy_to_iter(addr, bytes, i); |
|
goto out; |
|
} |
|
ret = ti->type->dax_copy_to_iter(ti, pgoff, addr, bytes, i); |
|
out: |
|
dm_put_live_table(md, srcu_idx); |
|
|
|
return ret; |
|
} |
|
|
|
static int dm_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff, |
|
size_t nr_pages) |
|
{ |
|
struct mapped_device *md = dax_get_private(dax_dev); |
|
sector_t sector = pgoff * PAGE_SECTORS; |
|
struct dm_target *ti; |
|
int ret = -EIO; |
|
int srcu_idx; |
|
|
|
ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
|
|
|
if (!ti) |
|
goto out; |
|
if (WARN_ON(!ti->type->dax_zero_page_range)) { |
|
/* |
|
* ->zero_page_range() is mandatory dax operation. If we are |
|
* here, something is wrong. |
|
*/ |
|
goto out; |
|
} |
|
ret = ti->type->dax_zero_page_range(ti, pgoff, nr_pages); |
|
out: |
|
dm_put_live_table(md, srcu_idx); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* A target may call dm_accept_partial_bio only from the map routine. It is |
|
* allowed for all bio types except REQ_PREFLUSH, REQ_OP_ZONE_* zone management |
|
* operations and REQ_OP_ZONE_APPEND (zone append writes). |
|
* |
|
* 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 | |
|
* +--------------------+---------------+-------+ |
|
* |
|
* <-------------- *tio->len_ptr ---------------> |
|
* <------- bi_size -------> |
|
* <-- n_sectors --> |
|
* |
|
* Region 1 was already iterated over with bio_advance or similar function. |
|
* (it may be empty if the target doesn't use bio_advance) |
|
* Region 2 is the remaining bio size that the target wants to process. |
|
* (it may be empty if region 1 is non-empty, although there is no reason |
|
* to make it empty) |
|
* The target requires that region 3 is to be sent in the next bio. |
|
* |
|
* If the target wants to receive multiple copies of the bio (via num_*bios, etc), |
|
* the partially processed part (the sum of regions 1+2) must be the same for all |
|
* copies of the bio. |
|
*/ |
|
void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) |
|
{ |
|
struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
|
unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; |
|
|
|
BUG_ON(bio->bi_opf & REQ_PREFLUSH); |
|
BUG_ON(op_is_zone_mgmt(bio_op(bio))); |
|
BUG_ON(bio_op(bio) == REQ_OP_ZONE_APPEND); |
|
BUG_ON(bi_size > *tio->len_ptr); |
|
BUG_ON(n_sectors > bi_size); |
|
|
|
*tio->len_ptr -= bi_size - n_sectors; |
|
bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_accept_partial_bio); |
|
|
|
static noinline void __set_swap_bios_limit(struct mapped_device *md, int latch) |
|
{ |
|
mutex_lock(&md->swap_bios_lock); |
|
while (latch < md->swap_bios) { |
|
cond_resched(); |
|
down(&md->swap_bios_semaphore); |
|
md->swap_bios--; |
|
} |
|
while (latch > md->swap_bios) { |
|
cond_resched(); |
|
up(&md->swap_bios_semaphore); |
|
md->swap_bios++; |
|
} |
|
mutex_unlock(&md->swap_bios_lock); |
|
} |
|
|
|
static blk_qc_t __map_bio(struct dm_target_io *tio) |
|
{ |
|
int r; |
|
sector_t sector; |
|
struct bio *clone = &tio->clone; |
|
struct dm_io *io = tio->io; |
|
struct dm_target *ti = tio->ti; |
|
blk_qc_t ret = BLK_QC_T_NONE; |
|
|
|
clone->bi_end_io = clone_endio; |
|
|
|
/* |
|
* Map the clone. If r == 0 we don't need to do |
|
* anything, the target has assumed ownership of |
|
* this io. |
|
*/ |
|
dm_io_inc_pending(io); |
|
sector = clone->bi_iter.bi_sector; |
|
|
|
if (unlikely(swap_bios_limit(ti, clone))) { |
|
struct mapped_device *md = io->md; |
|
int latch = get_swap_bios(); |
|
if (unlikely(latch != md->swap_bios)) |
|
__set_swap_bios_limit(md, latch); |
|
down(&md->swap_bios_semaphore); |
|
} |
|
|
|
/* |
|
* Check if the IO needs a special mapping due to zone append emulation |
|
* on zoned target. In this case, dm_zone_map_bio() calls the target |
|
* map operation. |
|
*/ |
|
if (dm_emulate_zone_append(io->md)) |
|
r = dm_zone_map_bio(tio); |
|
else |
|
r = ti->type->map(ti, clone); |
|
|
|
switch (r) { |
|
case DM_MAPIO_SUBMITTED: |
|
break; |
|
case DM_MAPIO_REMAPPED: |
|
/* the bio has been remapped so dispatch it */ |
|
trace_block_bio_remap(clone, bio_dev(io->orig_bio), sector); |
|
ret = submit_bio_noacct(clone); |
|
break; |
|
case DM_MAPIO_KILL: |
|
if (unlikely(swap_bios_limit(ti, clone))) { |
|
struct mapped_device *md = io->md; |
|
up(&md->swap_bios_semaphore); |
|
} |
|
free_tio(tio); |
|
dm_io_dec_pending(io, BLK_STS_IOERR); |
|
break; |
|
case DM_MAPIO_REQUEUE: |
|
if (unlikely(swap_bios_limit(ti, clone))) { |
|
struct mapped_device *md = io->md; |
|
up(&md->swap_bios_semaphore); |
|
} |
|
free_tio(tio); |
|
dm_io_dec_pending(io, BLK_STS_DM_REQUEUE); |
|
break; |
|
default: |
|
DMWARN("unimplemented target map return value: %d", r); |
|
BUG(); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) |
|
{ |
|
bio->bi_iter.bi_sector = sector; |
|
bio->bi_iter.bi_size = to_bytes(len); |
|
} |
|
|
|
/* |
|
* Creates a bio that consists of range of complete bvecs. |
|
*/ |
|
static int clone_bio(struct dm_target_io *tio, struct bio *bio, |
|
sector_t sector, unsigned len) |
|
{ |
|
struct bio *clone = &tio->clone; |
|
int r; |
|
|
|
__bio_clone_fast(clone, bio); |
|
|
|
r = bio_crypt_clone(clone, bio, GFP_NOIO); |
|
if (r < 0) |
|
return r; |
|
|
|
if (bio_integrity(bio)) { |
|
if (unlikely(!dm_target_has_integrity(tio->ti->type) && |
|
!dm_target_passes_integrity(tio->ti->type))) { |
|
DMWARN("%s: the target %s doesn't support integrity data.", |
|
dm_device_name(tio->io->md), |
|
tio->ti->type->name); |
|
return -EIO; |
|
} |
|
|
|
r = bio_integrity_clone(clone, bio, GFP_NOIO); |
|
if (r < 0) |
|
return r; |
|
} |
|
|
|
bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); |
|
clone->bi_iter.bi_size = to_bytes(len); |
|
|
|
if (bio_integrity(bio)) |
|
bio_integrity_trim(clone); |
|
|
|
return 0; |
|
} |
|
|
|
static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, |
|
struct dm_target *ti, unsigned num_bios) |
|
{ |
|
struct dm_target_io *tio; |
|
int try; |
|
|
|
if (!num_bios) |
|
return; |
|
|
|
if (num_bios == 1) { |
|
tio = alloc_tio(ci, ti, 0, GFP_NOIO); |
|
bio_list_add(blist, &tio->clone); |
|
return; |
|
} |
|
|
|
for (try = 0; try < 2; try++) { |
|
int bio_nr; |
|
struct bio *bio; |
|
|
|
if (try) |
|
mutex_lock(&ci->io->md->table_devices_lock); |
|
for (bio_nr = 0; bio_nr < num_bios; bio_nr++) { |
|
tio = alloc_tio(ci, ti, bio_nr, try ? GFP_NOIO : GFP_NOWAIT); |
|
if (!tio) |
|
break; |
|
|
|
bio_list_add(blist, &tio->clone); |
|
} |
|
if (try) |
|
mutex_unlock(&ci->io->md->table_devices_lock); |
|
if (bio_nr == num_bios) |
|
return; |
|
|
|
while ((bio = bio_list_pop(blist))) { |
|
tio = container_of(bio, struct dm_target_io, clone); |
|
free_tio(tio); |
|
} |
|
} |
|
} |
|
|
|
static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, |
|
struct dm_target_io *tio, unsigned *len) |
|
{ |
|
struct bio *clone = &tio->clone; |
|
|
|
tio->len_ptr = len; |
|
|
|
__bio_clone_fast(clone, ci->bio); |
|
if (len) |
|
bio_setup_sector(clone, ci->sector, *len); |
|
|
|
return __map_bio(tio); |
|
} |
|
|
|
static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, |
|
unsigned num_bios, unsigned *len) |
|
{ |
|
struct bio_list blist = BIO_EMPTY_LIST; |
|
struct bio *bio; |
|
struct dm_target_io *tio; |
|
|
|
alloc_multiple_bios(&blist, ci, ti, num_bios); |
|
|
|
while ((bio = bio_list_pop(&blist))) { |
|
tio = container_of(bio, struct dm_target_io, clone); |
|
(void) __clone_and_map_simple_bio(ci, tio, len); |
|
} |
|
} |
|
|
|
static int __send_empty_flush(struct clone_info *ci) |
|
{ |
|
unsigned target_nr = 0; |
|
struct dm_target *ti; |
|
struct bio flush_bio; |
|
|
|
/* |
|
* Use an on-stack bio for this, it's safe since we don't |
|
* need to reference it after submit. It's just used as |
|
* the basis for the clone(s). |
|
*/ |
|
bio_init(&flush_bio, NULL, 0); |
|
flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; |
|
bio_set_dev(&flush_bio, ci->io->md->disk->part0); |
|
|
|
ci->bio = &flush_bio; |
|
ci->sector_count = 0; |
|
|
|
BUG_ON(bio_has_data(ci->bio)); |
|
while ((ti = dm_table_get_target(ci->map, target_nr++))) |
|
__send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); |
|
|
|
bio_uninit(ci->bio); |
|
return 0; |
|
} |
|
|
|
static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, |
|
sector_t sector, unsigned *len) |
|
{ |
|
struct bio *bio = ci->bio; |
|
struct dm_target_io *tio; |
|
int r; |
|
|
|
tio = alloc_tio(ci, ti, 0, GFP_NOIO); |
|
tio->len_ptr = len; |
|
r = clone_bio(tio, bio, sector, *len); |
|
if (r < 0) { |
|
free_tio(tio); |
|
return r; |
|
} |
|
(void) __map_bio(tio); |
|
|
|
return 0; |
|
} |
|
|
|
static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti, |
|
unsigned num_bios) |
|
{ |
|
unsigned len; |
|
|
|
/* |
|
* 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. |
|
*/ |
|
if (!num_bios) |
|
return -EOPNOTSUPP; |
|
|
|
len = min_t(sector_t, ci->sector_count, |
|
max_io_len_target_boundary(ti, dm_target_offset(ti, ci->sector))); |
|
|
|
__send_duplicate_bios(ci, ti, num_bios, &len); |
|
|
|
ci->sector += len; |
|
ci->sector_count -= len; |
|
|
|
return 0; |
|
} |
|
|
|
static bool is_abnormal_io(struct bio *bio) |
|
{ |
|
bool r = false; |
|
|
|
switch (bio_op(bio)) { |
|
case REQ_OP_DISCARD: |
|
case REQ_OP_SECURE_ERASE: |
|
case REQ_OP_WRITE_SAME: |
|
case REQ_OP_WRITE_ZEROES: |
|
r = true; |
|
break; |
|
} |
|
|
|
return r; |
|
} |
|
|
|
static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti, |
|
int *result) |
|
{ |
|
struct bio *bio = ci->bio; |
|
unsigned num_bios = 0; |
|
|
|
switch (bio_op(bio)) { |
|
case REQ_OP_DISCARD: |
|
num_bios = ti->num_discard_bios; |
|
break; |
|
case REQ_OP_SECURE_ERASE: |
|
num_bios = ti->num_secure_erase_bios; |
|
break; |
|
case REQ_OP_WRITE_SAME: |
|
num_bios = ti->num_write_same_bios; |
|
break; |
|
case REQ_OP_WRITE_ZEROES: |
|
num_bios = ti->num_write_zeroes_bios; |
|
break; |
|
default: |
|
return false; |
|
} |
|
|
|
*result = __send_changing_extent_only(ci, ti, num_bios); |
|
return true; |
|
} |
|
|
|
/* |
|
* Select the correct strategy for processing a non-flush bio. |
|
*/ |
|
static int __split_and_process_non_flush(struct clone_info *ci) |
|
{ |
|
struct dm_target *ti; |
|
unsigned len; |
|
int r; |
|
|
|
ti = dm_table_find_target(ci->map, ci->sector); |
|
if (!ti) |
|
return -EIO; |
|
|
|
if (__process_abnormal_io(ci, ti, &r)) |
|
return r; |
|
|
|
len = min_t(sector_t, max_io_len(ti, ci->sector), 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; |
|
} |
|
|
|
static void init_clone_info(struct clone_info *ci, struct mapped_device *md, |
|
struct dm_table *map, struct bio *bio) |
|
{ |
|
ci->map = map; |
|
ci->io = alloc_io(md, bio); |
|
ci->sector = bio->bi_iter.bi_sector; |
|
} |
|
|
|
/* |
|
* Entry point to split a bio into clones and submit them to the targets. |
|
*/ |
|
static blk_qc_t __split_and_process_bio(struct mapped_device *md, |
|
struct dm_table *map, struct bio *bio) |
|
{ |
|
struct clone_info ci; |
|
blk_qc_t ret = BLK_QC_T_NONE; |
|
int error = 0; |
|
|
|
init_clone_info(&ci, md, map, bio); |
|
|
|
if (bio->bi_opf & REQ_PREFLUSH) { |
|
error = __send_empty_flush(&ci); |
|
/* dm_io_dec_pending submits any data associated with flush */ |
|
} else if (op_is_zone_mgmt(bio_op(bio))) { |
|
ci.bio = bio; |
|
ci.sector_count = 0; |
|
error = __split_and_process_non_flush(&ci); |
|
} else { |
|
ci.bio = bio; |
|
ci.sector_count = bio_sectors(bio); |
|
error = __split_and_process_non_flush(&ci); |
|
if (ci.sector_count && !error) { |
|
/* |
|
* Remainder must be passed to submit_bio_noacct() |
|
* so that it gets handled *after* bios already submitted |
|
* have been completely processed. |
|
* We take a clone of the original to store in |
|
* ci.io->orig_bio to be used by end_io_acct() and |
|
* for dec_pending to use for completion handling. |
|
*/ |
|
struct bio *b = bio_split(bio, bio_sectors(bio) - ci.sector_count, |
|
GFP_NOIO, &md->queue->bio_split); |
|
ci.io->orig_bio = b; |
|
|
|
bio_chain(b, bio); |
|
trace_block_split(b, bio->bi_iter.bi_sector); |
|
ret = submit_bio_noacct(bio); |
|
} |
|
} |
|
start_io_acct(ci.io); |
|
|
|
/* drop the extra reference count */ |
|
dm_io_dec_pending(ci.io, errno_to_blk_status(error)); |
|
return ret; |
|
} |
|
|
|
static blk_qc_t dm_submit_bio(struct bio *bio) |
|
{ |
|
struct mapped_device *md = bio->bi_bdev->bd_disk->private_data; |
|
blk_qc_t ret = BLK_QC_T_NONE; |
|
int srcu_idx; |
|
struct dm_table *map; |
|
|
|
map = dm_get_live_table(md, &srcu_idx); |
|
if (unlikely(!map)) { |
|
DMERR_LIMIT("%s: mapping table unavailable, erroring io", |
|
dm_device_name(md)); |
|
bio_io_error(bio); |
|
goto out; |
|
} |
|
|
|
/* If suspended, queue this IO for later */ |
|
if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { |
|
if (bio->bi_opf & REQ_NOWAIT) |
|
bio_wouldblock_error(bio); |
|
else if (bio->bi_opf & REQ_RAHEAD) |
|
bio_io_error(bio); |
|
else |
|
queue_io(md, bio); |
|
goto out; |
|
} |
|
|
|
/* |
|
* Use blk_queue_split() for abnormal IO (e.g. discard, writesame, etc) |
|
* otherwise associated queue_limits won't be imposed. |
|
*/ |
|
if (is_abnormal_io(bio)) |
|
blk_queue_split(&bio); |
|
|
|
ret = __split_and_process_bio(md, map, bio); |
|
out: |
|
dm_put_live_table(md, srcu_idx); |
|
return ret; |
|
} |
|
|
|
/*----------------------------------------------------------------- |
|
* An IDR is used to keep track of allocated minor numbers. |
|
*---------------------------------------------------------------*/ |
|
static void free_minor(int minor) |
|
{ |
|
spin_lock(&_minor_lock); |
|
idr_remove(&_minor_idr, minor); |
|
spin_unlock(&_minor_lock); |
|
} |
|
|
|
/* |
|
* See if the device with a specific minor # is free. |
|
*/ |
|
static int specific_minor(int minor) |
|
{ |
|
int r; |
|
|
|
if (minor >= (1 << MINORBITS)) |
|
return -EINVAL; |
|
|
|
idr_preload(GFP_KERNEL); |
|
spin_lock(&_minor_lock); |
|
|
|
r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); |
|
|
|
spin_unlock(&_minor_lock); |
|
idr_preload_end(); |
|
if (r < 0) |
|
return r == -ENOSPC ? -EBUSY : r; |
|
return 0; |
|
} |
|
|
|
static int next_free_minor(int *minor) |
|
{ |
|
int r; |
|
|
|
idr_preload(GFP_KERNEL); |
|
spin_lock(&_minor_lock); |
|
|
|
r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); |
|
|
|
spin_unlock(&_minor_lock); |
|
idr_preload_end(); |
|
if (r < 0) |
|
return r; |
|
*minor = r; |
|
return 0; |
|
} |
|
|
|
static const struct block_device_operations dm_blk_dops; |
|
static const struct block_device_operations dm_rq_blk_dops; |
|
static const struct dax_operations dm_dax_ops; |
|
|
|
static void dm_wq_work(struct work_struct *work); |
|
|
|
#ifdef CONFIG_BLK_INLINE_ENCRYPTION |
|
static void dm_queue_destroy_keyslot_manager(struct request_queue *q) |
|
{ |
|
dm_destroy_keyslot_manager(q->ksm); |
|
} |
|
|
|
#else /* CONFIG_BLK_INLINE_ENCRYPTION */ |
|
|
|
static inline void dm_queue_destroy_keyslot_manager(struct request_queue *q) |
|
{ |
|
} |
|
#endif /* !CONFIG_BLK_INLINE_ENCRYPTION */ |
|
|
|
static void cleanup_mapped_device(struct mapped_device *md) |
|
{ |
|
if (md->wq) |
|
destroy_workqueue(md->wq); |
|
bioset_exit(&md->bs); |
|
bioset_exit(&md->io_bs); |
|
|
|
if (md->dax_dev) { |
|
kill_dax(md->dax_dev); |
|
put_dax(md->dax_dev); |
|
md->dax_dev = NULL; |
|
} |
|
|
|
if (md->disk) { |
|
spin_lock(&_minor_lock); |
|
md->disk->private_data = NULL; |
|
spin_unlock(&_minor_lock); |
|
if (dm_get_md_type(md) != DM_TYPE_NONE) { |
|
dm_sysfs_exit(md); |
|
del_gendisk(md->disk); |
|
} |
|
dm_queue_destroy_keyslot_manager(md->queue); |
|
blk_cleanup_disk(md->disk); |
|
} |
|
|
|
cleanup_srcu_struct(&md->io_barrier); |
|
|
|
mutex_destroy(&md->suspend_lock); |
|
mutex_destroy(&md->type_lock); |
|
mutex_destroy(&md->table_devices_lock); |
|
mutex_destroy(&md->swap_bios_lock); |
|
|
|
dm_mq_cleanup_mapped_device(md); |
|
dm_cleanup_zoned_dev(md); |
|
} |
|
|
|
/* |
|
* Allocate and initialise a blank device with a given minor. |
|
*/ |
|
static struct mapped_device *alloc_dev(int minor) |
|
{ |
|
int r, numa_node_id = dm_get_numa_node(); |
|
struct mapped_device *md; |
|
void *old_md; |
|
|
|
md = kvzalloc_node(sizeof(*md), GFP_KERNEL, numa_node_id); |
|
if (!md) { |
|
DMWARN("unable to allocate device, out of memory."); |
|
return NULL; |
|
} |
|
|
|
if (!try_module_get(THIS_MODULE)) |
|
goto bad_module_get; |
|
|
|
/* get a minor number for the dev */ |
|
if (minor == DM_ANY_MINOR) |
|
r = next_free_minor(&minor); |
|
else |
|
r = specific_minor(minor); |
|
if (r < 0) |
|
goto bad_minor; |
|
|
|
r = init_srcu_struct(&md->io_barrier); |
|
if (r < 0) |
|
goto bad_io_barrier; |
|
|
|
md->numa_node_id = numa_node_id; |
|
md->init_tio_pdu = false; |
|
md->type = DM_TYPE_NONE; |
|
mutex_init(&md->suspend_lock); |
|
mutex_init(&md->type_lock); |
|
mutex_init(&md->table_devices_lock); |
|
spin_lock_init(&md->deferred_lock); |
|
atomic_set(&md->holders, 1); |
|
atomic_set(&md->open_count, 0); |
|
atomic_set(&md->event_nr, 0); |
|
atomic_set(&md->uevent_seq, 0); |
|
INIT_LIST_HEAD(&md->uevent_list); |
|
INIT_LIST_HEAD(&md->table_devices); |
|
spin_lock_init(&md->uevent_lock); |
|
|
|
/* |
|
* default to bio-based until DM table is loaded and md->type |
|
* established. If request-based table is loaded: blk-mq will |
|
* override accordingly. |
|
*/ |
|
md->disk = blk_alloc_disk(md->numa_node_id); |
|
if (!md->disk) |
|
goto bad; |
|
md->queue = md->disk->queue; |
|
|
|
init_waitqueue_head(&md->wait); |
|
INIT_WORK(&md->work, dm_wq_work); |
|
init_waitqueue_head(&md->eventq); |
|
init_completion(&md->kobj_holder.completion); |
|
|
|
md->swap_bios = get_swap_bios(); |
|
sema_init(&md->swap_bios_semaphore, md->swap_bios); |
|
mutex_init(&md->swap_bios_lock); |
|
|
|
md->disk->major = _major; |
|
md->disk->first_minor = minor; |
|
md->disk->minors = 1; |
|
md->disk->fops = &dm_blk_dops; |
|
md->disk->queue = md->queue; |
|
md->disk->private_data = md; |
|
sprintf(md->disk->disk_name, "dm-%d", minor); |
|
|
|
if (IS_ENABLED(CONFIG_DAX_DRIVER)) { |
|
md->dax_dev = alloc_dax(md, md->disk->disk_name, |
|
&dm_dax_ops, 0); |
|
if (IS_ERR(md->dax_dev)) { |
|
md->dax_dev = NULL; |
|
goto bad; |
|
} |
|
} |
|
|
|
format_dev_t(md->name, MKDEV(_major, minor)); |
|
|
|
md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); |
|
if (!md->wq) |
|
goto bad; |
|
|
|
dm_stats_init(&md->stats); |
|
|
|
/* Populate the mapping, nobody knows we exist yet */ |
|
spin_lock(&_minor_lock); |
|
old_md = idr_replace(&_minor_idr, md, minor); |
|
spin_unlock(&_minor_lock); |
|
|
|
BUG_ON(old_md != MINOR_ALLOCED); |
|
|
|
return md; |
|
|
|
bad: |
|
cleanup_mapped_device(md); |
|
bad_io_barrier: |
|
free_minor(minor); |
|
bad_minor: |
|
module_put(THIS_MODULE); |
|
bad_module_get: |
|
kvfree(md); |
|
return NULL; |
|
} |
|
|
|
static void unlock_fs(struct mapped_device *md); |
|
|
|
static void free_dev(struct mapped_device *md) |
|
{ |
|
int minor = MINOR(disk_devt(md->disk)); |
|
|
|
unlock_fs(md); |
|
|
|
cleanup_mapped_device(md); |
|
|
|
free_table_devices(&md->table_devices); |
|
dm_stats_cleanup(&md->stats); |
|
free_minor(minor); |
|
|
|
module_put(THIS_MODULE); |
|
kvfree(md); |
|
} |
|
|
|
static int __bind_mempools(struct mapped_device *md, struct dm_table *t) |
|
{ |
|
struct dm_md_mempools *p = dm_table_get_md_mempools(t); |
|
int ret = 0; |
|
|
|
if (dm_table_bio_based(t)) { |
|
/* |
|
* The md may already have mempools that need changing. |
|
* If so, reload bioset because front_pad may have changed |
|
* because a different table was loaded. |
|
*/ |
|
bioset_exit(&md->bs); |
|
bioset_exit(&md->io_bs); |
|
|
|
} else if (bioset_initialized(&md->bs)) { |
|
/* |
|
* There's no need to reload with request-based dm |
|
* because the size of front_pad doesn't change. |
|
* Note for future: If you are to reload bioset, |
|
* prep-ed requests in the queue may refer |
|
* to bio from the old bioset, so you must walk |
|
* through the queue to unprep. |
|
*/ |
|
goto out; |
|
} |
|
|
|
BUG_ON(!p || |
|
bioset_initialized(&md->bs) || |
|
bioset_initialized(&md->io_bs)); |
|
|
|
ret = bioset_init_from_src(&md->bs, &p->bs); |
|
if (ret) |
|
goto out; |
|
ret = bioset_init_from_src(&md->io_bs, &p->io_bs); |
|
if (ret) |
|
bioset_exit(&md->bs); |
|
out: |
|
/* mempool bind completed, no longer need any mempools in the table */ |
|
dm_table_free_md_mempools(t); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Bind a table to the device. |
|
*/ |
|
static void event_callback(void *context) |
|
{ |
|
unsigned long flags; |
|
LIST_HEAD(uevents); |
|
struct mapped_device *md = (struct mapped_device *) context; |
|
|
|
spin_lock_irqsave(&md->uevent_lock, flags); |
|
list_splice_init(&md->uevent_list, &uevents); |
|
spin_unlock_irqrestore(&md->uevent_lock, flags); |
|
|
|
dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
|
|
|
atomic_inc(&md->event_nr); |
|
wake_up(&md->eventq); |
|
dm_issue_global_event(); |
|
} |
|
|
|
/* |
|
* Returns old map, which caller must destroy. |
|
*/ |
|
static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, |
|
struct queue_limits *limits) |
|
{ |
|
struct dm_table *old_map; |
|
struct request_queue *q = md->queue; |
|
bool request_based = dm_table_request_based(t); |
|
sector_t size; |
|
int ret; |
|
|
|
lockdep_assert_held(&md->suspend_lock); |
|
|
|
size = dm_table_get_size(t); |
|
|
|
/* |
|
* Wipe any geometry if the size of the table changed. |
|
*/ |
|
if (size != dm_get_size(md)) |
|
memset(&md->geometry, 0, sizeof(md->geometry)); |
|
|
|
if (!get_capacity(md->disk)) |
|
set_capacity(md->disk, size); |
|
else |
|
set_capacity_and_notify(md->disk, size); |
|
|
|
dm_table_event_callback(t, event_callback, md); |
|
|
|
/* |
|
* The queue hasn't been stopped yet, if the old table type wasn't |
|
* for request-based during suspension. So stop it to prevent |
|
* I/O mapping before resume. |
|
* This must be done before setting the queue restrictions, |
|
* because request-based dm may be run just after the setting. |
|
*/ |
|
if (request_based) |
|
dm_stop_queue(q); |
|
|
|
if (request_based) { |
|
/* |
|
* Leverage the fact that request-based DM targets are |
|
* immutable singletons - used to optimize dm_mq_queue_rq. |
|
*/ |
|
md->immutable_target = dm_table_get_immutable_target(t); |
|
} |
|
|
|
ret = __bind_mempools(md, t); |
|
if (ret) { |
|
old_map = ERR_PTR(ret); |
|
goto out; |
|
} |
|
|
|
ret = dm_table_set_restrictions(t, q, limits); |
|
if (ret) { |
|
old_map = ERR_PTR(ret); |
|
goto out; |
|
} |
|
|
|
old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
|
rcu_assign_pointer(md->map, (void *)t); |
|
md->immutable_target_type = dm_table_get_immutable_target_type(t); |
|
|
|
if (old_map) |
|
dm_sync_table(md); |
|
|
|
out: |
|
return old_map; |
|
} |
|
|
|
/* |
|
* Returns unbound table for the caller to free. |
|
*/ |
|
static struct dm_table *__unbind(struct mapped_device *md) |
|
{ |
|
struct dm_table *map = rcu_dereference_protected(md->map, 1); |
|
|
|
if (!map) |
|
return NULL; |
|
|
|
dm_table_event_callback(map, NULL, NULL); |
|
RCU_INIT_POINTER(md->map, NULL); |
|
dm_sync_table(md); |
|
|
|
return map; |
|
} |
|
|
|
/* |
|
* Constructor for a new device. |
|
*/ |
|
int dm_create(int minor, struct mapped_device **result) |
|
{ |
|
struct mapped_device *md; |
|
|
|
md = alloc_dev(minor); |
|
if (!md) |
|
return -ENXIO; |
|
|
|
dm_ima_reset_data(md); |
|
|
|
*result = md; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Functions to manage md->type. |
|
* All are required to hold md->type_lock. |
|
*/ |
|
void dm_lock_md_type(struct mapped_device *md) |
|
{ |
|
mutex_lock(&md->type_lock); |
|
} |
|
|
|
void dm_unlock_md_type(struct mapped_device *md) |
|
{ |
|
mutex_unlock(&md->type_lock); |
|
} |
|
|
|
void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type) |
|
{ |
|
BUG_ON(!mutex_is_locked(&md->type_lock)); |
|
md->type = type; |
|
} |
|
|
|
enum dm_queue_mode dm_get_md_type(struct mapped_device *md) |
|
{ |
|
return md->type; |
|
} |
|
|
|
struct target_type *dm_get_immutable_target_type(struct mapped_device *md) |
|
{ |
|
return md->immutable_target_type; |
|
} |
|
|
|
/* |
|
* The queue_limits are only valid as long as you have a reference |
|
* count on 'md'. |
|
*/ |
|
struct queue_limits *dm_get_queue_limits(struct mapped_device *md) |
|
{ |
|
BUG_ON(!atomic_read(&md->holders)); |
|
return &md->queue->limits; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_get_queue_limits); |
|
|
|
/* |
|
* Setup the DM device's queue based on md's type |
|
*/ |
|
int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t) |
|
{ |
|
enum dm_queue_mode type = dm_table_get_type(t); |
|
struct queue_limits limits; |
|
int r; |
|
|
|
switch (type) { |
|
case DM_TYPE_REQUEST_BASED: |
|
md->disk->fops = &dm_rq_blk_dops; |
|
r = dm_mq_init_request_queue(md, t); |
|
if (r) { |
|
DMERR("Cannot initialize queue for request-based dm mapped device"); |
|
return r; |
|
} |
|
break; |
|
case DM_TYPE_BIO_BASED: |
|
case DM_TYPE_DAX_BIO_BASED: |
|
break; |
|
case DM_TYPE_NONE: |
|
WARN_ON_ONCE(true); |
|
break; |
|
} |
|
|
|
r = dm_calculate_queue_limits(t, &limits); |
|
if (r) { |
|
DMERR("Cannot calculate initial queue limits"); |
|
return r; |
|
} |
|
r = dm_table_set_restrictions(t, md->queue, &limits); |
|
if (r) |
|
return r; |
|
|
|
add_disk(md->disk); |
|
|
|
r = dm_sysfs_init(md); |
|
if (r) { |
|
del_gendisk(md->disk); |
|
return r; |
|
} |
|
md->type = type; |
|
return 0; |
|
} |
|
|
|
struct mapped_device *dm_get_md(dev_t dev) |
|
{ |
|
struct mapped_device *md; |
|
unsigned minor = MINOR(dev); |
|
|
|
if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) |
|
return NULL; |
|
|
|
spin_lock(&_minor_lock); |
|
|
|
md = idr_find(&_minor_idr, minor); |
|
if (!md || md == MINOR_ALLOCED || (MINOR(disk_devt(dm_disk(md))) != minor) || |
|
test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) { |
|
md = NULL; |
|
goto out; |
|
} |
|
dm_get(md); |
|
out: |
|
spin_unlock(&_minor_lock); |
|
|
|
return md; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_get_md); |
|
|
|
void *dm_get_mdptr(struct mapped_device *md) |
|
{ |
|
return md->interface_ptr; |
|
} |
|
|
|
void dm_set_mdptr(struct mapped_device *md, void *ptr) |
|
{ |
|
md->interface_ptr = ptr; |
|
} |
|
|
|
void dm_get(struct mapped_device *md) |
|
{ |
|
atomic_inc(&md->holders); |
|
BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
|
} |
|
|
|
int dm_hold(struct mapped_device *md) |
|
{ |
|
spin_lock(&_minor_lock); |
|
if (test_bit(DMF_FREEING, &md->flags)) { |
|
spin_unlock(&_minor_lock); |
|
return -EBUSY; |
|
} |
|
dm_get(md); |
|
spin_unlock(&_minor_lock); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_hold); |
|
|
|
const char *dm_device_name(struct mapped_device *md) |
|
{ |
|
return md->name; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_device_name); |
|
|
|
static void __dm_destroy(struct mapped_device *md, bool wait) |
|
{ |
|
struct dm_table *map; |
|
int srcu_idx; |
|
|
|
might_sleep(); |
|
|
|
spin_lock(&_minor_lock); |
|
idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); |
|
set_bit(DMF_FREEING, &md->flags); |
|
spin_unlock(&_minor_lock); |
|
|
|
blk_mark_disk_dead(md->disk); |
|
|
|
/* |
|
* Take suspend_lock so that presuspend and postsuspend methods |
|
* do not race with internal suspend. |
|
*/ |
|
mutex_lock(&md->suspend_lock); |
|
map = dm_get_live_table(md, &srcu_idx); |
|
if (!dm_suspended_md(md)) { |
|
dm_table_presuspend_targets(map); |
|
set_bit(DMF_SUSPENDED, &md->flags); |
|
set_bit(DMF_POST_SUSPENDING, &md->flags); |
|
dm_table_postsuspend_targets(map); |
|
} |
|
/* dm_put_live_table must be before msleep, otherwise deadlock is possible */ |
|
dm_put_live_table(md, srcu_idx); |
|
mutex_unlock(&md->suspend_lock); |
|
|
|
/* |
|
* Rare, but there may be I/O requests still going to complete, |
|
* for example. Wait for all references to disappear. |
|
* No one should increment the reference count of the mapped_device, |
|
* after the mapped_device state becomes DMF_FREEING. |
|
*/ |
|
if (wait) |
|
while (atomic_read(&md->holders)) |
|
msleep(1); |
|
else if (atomic_read(&md->holders)) |
|
DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", |
|
dm_device_name(md), atomic_read(&md->holders)); |
|
|
|
dm_table_destroy(__unbind(md)); |
|
free_dev(md); |
|
} |
|
|
|
void dm_destroy(struct mapped_device *md) |
|
{ |
|
__dm_destroy(md, true); |
|
} |
|
|
|
void dm_destroy_immediate(struct mapped_device *md) |
|
{ |
|
__dm_destroy(md, false); |
|
} |
|
|
|
void dm_put(struct mapped_device *md) |
|
{ |
|
atomic_dec(&md->holders); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_put); |
|
|
|
static bool md_in_flight_bios(struct mapped_device *md) |
|
{ |
|
int cpu; |
|
struct block_device *part = dm_disk(md)->part0; |
|
long sum = 0; |
|
|
|
for_each_possible_cpu(cpu) { |
|
sum += part_stat_local_read_cpu(part, in_flight[0], cpu); |
|
sum += part_stat_local_read_cpu(part, in_flight[1], cpu); |
|
} |
|
|
|
return sum != 0; |
|
} |
|
|
|
static int dm_wait_for_bios_completion(struct mapped_device *md, unsigned int task_state) |
|
{ |
|
int r = 0; |
|
DEFINE_WAIT(wait); |
|
|
|
while (true) { |
|
prepare_to_wait(&md->wait, &wait, task_state); |
|
|
|
if (!md_in_flight_bios(md)) |
|
break; |
|
|
|
if (signal_pending_state(task_state, current)) { |
|
r = -EINTR; |
|
break; |
|
} |
|
|
|
io_schedule(); |
|
} |
|
finish_wait(&md->wait, &wait); |
|
|
|
return r; |
|
} |
|
|
|
static int dm_wait_for_completion(struct mapped_device *md, unsigned int task_state) |
|
{ |
|
int r = 0; |
|
|
|
if (!queue_is_mq(md->queue)) |
|
return dm_wait_for_bios_completion(md, task_state); |
|
|
|
while (true) { |
|
if (!blk_mq_queue_inflight(md->queue)) |
|
break; |
|
|
|
if (signal_pending_state(task_state, current)) { |
|
r = -EINTR; |
|
break; |
|
} |
|
|
|
msleep(5); |
|
} |
|
|
|
return r; |
|
} |
|
|
|
/* |
|
* Process the deferred bios |
|
*/ |
|
static void dm_wq_work(struct work_struct *work) |
|
{ |
|
struct mapped_device *md = container_of(work, struct mapped_device, work); |
|
struct bio *bio; |
|
|
|
while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
|
spin_lock_irq(&md->deferred_lock); |
|
bio = bio_list_pop(&md->deferred); |
|
spin_unlock_irq(&md->deferred_lock); |
|
|
|
if (!bio) |
|
break; |
|
|
|
submit_bio_noacct(bio); |
|
} |
|
} |
|
|
|
static void dm_queue_flush(struct mapped_device *md) |
|
{ |
|
clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
|
smp_mb__after_atomic(); |
|
queue_work(md->wq, &md->work); |
|
} |
|
|
|
/* |
|
* Swap in a new table, returning the old one for the caller to destroy. |
|
*/ |
|
struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
|
{ |
|
struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); |
|
struct queue_limits limits; |
|
int r; |
|
|
|
mutex_lock(&md->suspend_lock); |
|
|
|
/* device must be suspended */ |
|
if (!dm_suspended_md(md)) |
|
goto out; |
|
|
|
/* |
|
* If the new table has no data devices, retain the existing limits. |
|
* This helps multipath with queue_if_no_path if all paths disappear, |
|
* then new I/O is queued based on these limits, and then some paths |
|
* reappear. |
|
*/ |
|
if (dm_table_has_no_data_devices(table)) { |
|
live_map = dm_get_live_table_fast(md); |
|
if (live_map) |
|
limits = md->queue->limits; |
|
dm_put_live_table_fast(md); |
|
} |
|
|
|
if (!live_map) { |
|
r = dm_calculate_queue_limits(table, &limits); |
|
if (r) { |
|
map = ERR_PTR(r); |
|
goto out; |
|
} |
|
} |
|
|
|
map = __bind(md, table, &limits); |
|
dm_issue_global_event(); |
|
|
|
out: |
|
mutex_unlock(&md->suspend_lock); |
|
return map; |
|
} |
|
|
|
/* |
|
* Functions to lock and unlock any filesystem running on the |
|
* device. |
|
*/ |
|
static int lock_fs(struct mapped_device *md) |
|
{ |
|
int r; |
|
|
|
WARN_ON(test_bit(DMF_FROZEN, &md->flags)); |
|
|
|
r = freeze_bdev(md->disk->part0); |
|
if (!r) |
|
set_bit(DMF_FROZEN, &md->flags); |
|
return r; |
|
} |
|
|
|
static void unlock_fs(struct mapped_device *md) |
|
{ |
|
if (!test_bit(DMF_FROZEN, &md->flags)) |
|
return; |
|
thaw_bdev(md->disk->part0); |
|
clear_bit(DMF_FROZEN, &md->flags); |
|
} |
|
|
|
/* |
|
* @suspend_flags: DM_SUSPEND_LOCKFS_FLAG and/or DM_SUSPEND_NOFLUSH_FLAG |
|
* @task_state: e.g. TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE |
|
* @dmf_suspended_flag: DMF_SUSPENDED or DMF_SUSPENDED_INTERNALLY |
|
* |
|
* If __dm_suspend returns 0, the device is completely quiescent |
|
* now. There is no request-processing activity. All new requests |
|
* are being added to md->deferred list. |
|
*/ |
|
static int __dm_suspend(struct mapped_device *md, struct dm_table *map, |
|
unsigned suspend_flags, unsigned int task_state, |
|
int dmf_suspended_flag) |
|
{ |
|
bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; |
|
bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; |
|
int r; |
|
|
|
lockdep_assert_held(&md->suspend_lock); |
|
|
|
/* |
|
* DMF_NOFLUSH_SUSPENDING must be set before presuspend. |
|
* This flag is cleared before dm_suspend returns. |
|
*/ |
|
if (noflush) |
|
set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
|
else |
|
DMDEBUG("%s: suspending with flush", dm_device_name(md)); |
|
|
|
/* |
|
* This gets reverted if there's an error later and the targets |
|
* provide the .presuspend_undo hook. |
|
*/ |
|
dm_table_presuspend_targets(map); |
|
|
|
/* |
|
* Flush I/O to the device. |
|
* Any I/O submitted after lock_fs() may not be flushed. |
|
* noflush takes precedence over do_lockfs. |
|
* (lock_fs() flushes I/Os and waits for them to complete.) |
|
*/ |
|
if (!noflush && do_lockfs) { |
|
r = lock_fs(md); |
|
if (r) { |
|
dm_table_presuspend_undo_targets(map); |
|
return r; |
|
} |
|
} |
|
|
|
/* |
|
* Here we must make sure that no processes are submitting requests |
|
* to target drivers i.e. no one may be executing |
|
* __split_and_process_bio from dm_submit_bio. |
|
* |
|
* To get all processes out of __split_and_process_bio in dm_submit_bio, |
|
* we take the write lock. To prevent any process from reentering |
|
* __split_and_process_bio from dm_submit_bio and quiesce the thread |
|
* (dm_wq_work), we set DMF_BLOCK_IO_FOR_SUSPEND and call |
|
* flush_workqueue(md->wq). |
|
*/ |
|
set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
|
if (map) |
|
synchronize_srcu(&md->io_barrier); |
|
|
|
/* |
|
* Stop md->queue before flushing md->wq in case request-based |
|
* dm defers requests to md->wq from md->queue. |
|
*/ |
|
if (dm_request_based(md)) |
|
dm_stop_queue(md->queue); |
|
|
|
flush_workqueue(md->wq); |
|
|
|
/* |
|
* At this point no more requests are entering target request routines. |
|
* We call dm_wait_for_completion to wait for all existing requests |
|
* to finish. |
|
*/ |
|
r = dm_wait_for_completion(md, task_state); |
|
if (!r) |
|
set_bit(dmf_suspended_flag, &md->flags); |
|
|
|
if (noflush) |
|
clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
|
if (map) |
|
synchronize_srcu(&md->io_barrier); |
|
|
|
/* were we interrupted ? */ |
|
if (r < 0) { |
|
dm_queue_flush(md); |
|
|
|
if (dm_request_based(md)) |
|
dm_start_queue(md->queue); |
|
|
|
unlock_fs(md); |
|
dm_table_presuspend_undo_targets(map); |
|
/* pushback list is already flushed, so skip flush */ |
|
} |
|
|
|
return r; |
|
} |
|
|
|
/* |
|
* We need to be able to change a mapping table under a mounted |
|
* filesystem. For example we might want to move some data in |
|
* the background. Before the table can be swapped with |
|
* dm_bind_table, dm_suspend must be called to flush any in |
|
* flight bios and ensure that any further io gets deferred. |
|
*/ |
|
/* |
|
* Suspend mechanism in request-based dm. |
|
* |
|
* 1. Flush all I/Os by lock_fs() if needed. |
|
* 2. Stop dispatching any I/O by stopping the request_queue. |
|
* 3. Wait for all in-flight I/Os to be completed or requeued. |
|
* |
|
* To abort suspend, start the request_queue. |
|
*/ |
|
int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
|
{ |
|
struct dm_table *map = NULL; |
|
int r = 0; |
|
|
|
retry: |
|
mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); |
|
|
|
if (dm_suspended_md(md)) { |
|
r = -EINVAL; |
|
goto out_unlock; |
|
} |
|
|
|
if (dm_suspended_internally_md(md)) { |
|
/* already internally suspended, wait for internal resume */ |
|
mutex_unlock(&md->suspend_lock); |
|
r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); |
|
if (r) |
|
return r; |
|
goto retry; |
|
} |
|
|
|
map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
|
|
|
r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED); |
|
if (r) |
|
goto out_unlock; |
|
|
|
set_bit(DMF_POST_SUSPENDING, &md->flags); |
|
dm_table_postsuspend_targets(map); |
|
clear_bit(DMF_POST_SUSPENDING, &md->flags); |
|
|
|
out_unlock: |
|
mutex_unlock(&md->suspend_lock); |
|
return r; |
|
} |
|
|
|
static int __dm_resume(struct mapped_device *md, struct dm_table *map) |
|
{ |
|
if (map) { |
|
int r = dm_table_resume_targets(map); |
|
if (r) |
|
return r; |
|
} |
|
|
|
dm_queue_flush(md); |
|
|
|
/* |
|
* Flushing deferred I/Os must be done after targets are resumed |
|
* so that mapping of targets can work correctly. |
|
* Request-based dm is queueing the deferred I/Os in its request_queue. |
|
*/ |
|
if (dm_request_based(md)) |
|
dm_start_queue(md->queue); |
|
|
|
unlock_fs(md); |
|
|
|
return 0; |
|
} |
|
|
|
int dm_resume(struct mapped_device *md) |
|
{ |
|
int r; |
|
struct dm_table *map = NULL; |
|
|
|
retry: |
|
r = -EINVAL; |
|
mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); |
|
|
|
if (!dm_suspended_md(md)) |
|
goto out; |
|
|
|
if (dm_suspended_internally_md(md)) { |
|
/* already internally suspended, wait for internal resume */ |
|
mutex_unlock(&md->suspend_lock); |
|
r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); |
|
if (r) |
|
return r; |
|
goto retry; |
|
} |
|
|
|
map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
|
if (!map || !dm_table_get_size(map)) |
|
goto out; |
|
|
|
r = __dm_resume(md, map); |
|
if (r) |
|
goto out; |
|
|
|
clear_bit(DMF_SUSPENDED, &md->flags); |
|
out: |
|
mutex_unlock(&md->suspend_lock); |
|
|
|
return r; |
|
} |
|
|
|
/* |
|
* Internal suspend/resume works like userspace-driven suspend. It waits |
|
* until all bios finish and prevents issuing new bios to the target drivers. |
|
* It may be used only from the kernel. |
|
*/ |
|
|
|
static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) |
|
{ |
|
struct dm_table *map = NULL; |
|
|
|
lockdep_assert_held(&md->suspend_lock); |
|
|
|
if (md->internal_suspend_count++) |
|
return; /* nested internal suspend */ |
|
|
|
if (dm_suspended_md(md)) { |
|
set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); |
|
return; /* nest suspend */ |
|
} |
|
|
|
map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
|
|
|
/* |
|
* Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is |
|
* supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend |
|
* would require changing .presuspend to return an error -- avoid this |
|
* until there is a need for more elaborate variants of internal suspend. |
|
*/ |
|
(void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE, |
|
DMF_SUSPENDED_INTERNALLY); |
|
|
|
set_bit(DMF_POST_SUSPENDING, &md->flags); |
|
dm_table_postsuspend_targets(map); |
|
clear_bit(DMF_POST_SUSPENDING, &md->flags); |
|
} |
|
|
|
static void __dm_internal_resume(struct mapped_device *md) |
|
{ |
|
BUG_ON(!md->internal_suspend_count); |
|
|
|
if (--md->internal_suspend_count) |
|
return; /* resume from nested internal suspend */ |
|
|
|
if (dm_suspended_md(md)) |
|
goto done; /* resume from nested suspend */ |
|
|
|
/* |
|
* NOTE: existing callers don't need to call dm_table_resume_targets |
|
* (which may fail -- so best to avoid it for now by passing NULL map) |
|
*/ |
|
(void) __dm_resume(md, NULL); |
|
|
|
done: |
|
clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); |
|
smp_mb__after_atomic(); |
|
wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); |
|
} |
|
|
|
void dm_internal_suspend_noflush(struct mapped_device *md) |
|
{ |
|
mutex_lock(&md->suspend_lock); |
|
__dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); |
|
mutex_unlock(&md->suspend_lock); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); |
|
|
|
void dm_internal_resume(struct mapped_device *md) |
|
{ |
|
mutex_lock(&md->suspend_lock); |
|
__dm_internal_resume(md); |
|
mutex_unlock(&md->suspend_lock); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_internal_resume); |
|
|
|
/* |
|
* Fast variants of internal suspend/resume hold md->suspend_lock, |
|
* which prevents interaction with userspace-driven suspend. |
|
*/ |
|
|
|
void dm_internal_suspend_fast(struct mapped_device *md) |
|
{ |
|
mutex_lock(&md->suspend_lock); |
|
if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
|
return; |
|
|
|
set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
|
synchronize_srcu(&md->io_barrier); |
|
flush_workqueue(md->wq); |
|
dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_internal_suspend_fast); |
|
|
|
void dm_internal_resume_fast(struct mapped_device *md) |
|
{ |
|
if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
|
goto done; |
|
|
|
dm_queue_flush(md); |
|
|
|
done: |
|
mutex_unlock(&md->suspend_lock); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_internal_resume_fast); |
|
|
|
/*----------------------------------------------------------------- |
|
* Event notification. |
|
*---------------------------------------------------------------*/ |
|
int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
|
unsigned cookie) |
|
{ |
|
int r; |
|
unsigned noio_flag; |
|
char udev_cookie[DM_COOKIE_LENGTH]; |
|
char *envp[] = { udev_cookie, NULL }; |
|
|
|
noio_flag = memalloc_noio_save(); |
|
|
|
if (!cookie) |
|
r = kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
|
else { |
|
snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", |
|
DM_COOKIE_ENV_VAR_NAME, cookie); |
|
r = kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
|
action, envp); |
|
} |
|
|
|
memalloc_noio_restore(noio_flag); |
|
|
|
return r; |
|
} |
|
|
|
uint32_t dm_next_uevent_seq(struct mapped_device *md) |
|
{ |
|
return atomic_add_return(1, &md->uevent_seq); |
|
} |
|
|
|
uint32_t dm_get_event_nr(struct mapped_device *md) |
|
{ |
|
return atomic_read(&md->event_nr); |
|
} |
|
|
|
int dm_wait_event(struct mapped_device *md, int event_nr) |
|
{ |
|
return wait_event_interruptible(md->eventq, |
|
(event_nr != atomic_read(&md->event_nr))); |
|
} |
|
|
|
void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
|
{ |
|
unsigned long flags; |
|
|
|
spin_lock_irqsave(&md->uevent_lock, flags); |
|
list_add(elist, &md->uevent_list); |
|
spin_unlock_irqrestore(&md->uevent_lock, flags); |
|
} |
|
|
|
/* |
|
* The gendisk is only valid as long as you have a reference |
|
* count on 'md'. |
|
*/ |
|
struct gendisk *dm_disk(struct mapped_device *md) |
|
{ |
|
return md->disk; |
|
} |
|
EXPORT_SYMBOL_GPL(dm_disk); |
|
|
|
struct kobject *dm_kobject(struct mapped_device *md) |
|
{ |
|
return &md->kobj_holder.kobj; |
|
} |
|
|
|
struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
|
{ |
|
struct mapped_device *md; |
|
|
|
md = container_of(kobj, struct mapped_device, kobj_holder.kobj); |
|
|
|
spin_lock(&_minor_lock); |
|
if (test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) { |
|
md = NULL; |
|
goto out; |
|
} |
|
dm_get(md); |
|
out: |
|
spin_unlock(&_minor_lock); |
|
|
|
return md; |
|
} |
|
|
|
int dm_suspended_md(struct mapped_device *md) |
|
{ |
|
return test_bit(DMF_SUSPENDED, &md->flags); |
|
} |
|
|
|
static int dm_post_suspending_md(struct mapped_device *md) |
|
{ |
|
return test_bit(DMF_POST_SUSPENDING, &md->flags); |
|
} |
|
|
|
int dm_suspended_internally_md(struct mapped_device *md) |
|
{ |
|
return test_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); |
|
} |
|
|
|
int dm_test_deferred_remove_flag(struct mapped_device *md) |
|
{ |
|
return test_bit(DMF_DEFERRED_REMOVE, &md->flags); |
|
} |
|
|
|
int dm_suspended(struct dm_target *ti) |
|
{ |
|
return dm_suspended_md(ti->table->md); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_suspended); |
|
|
|
int dm_post_suspending(struct dm_target *ti) |
|
{ |
|
return dm_post_suspending_md(ti->table->md); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_post_suspending); |
|
|
|
int dm_noflush_suspending(struct dm_target *ti) |
|
{ |
|
return __noflush_suspending(ti->table->md); |
|
} |
|
EXPORT_SYMBOL_GPL(dm_noflush_suspending); |
|
|
|
struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type, |
|
unsigned integrity, unsigned per_io_data_size, |
|
unsigned min_pool_size) |
|
{ |
|
struct dm_md_mempools *pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id); |
|
unsigned int pool_size = 0; |
|
unsigned int front_pad, io_front_pad; |
|
int ret; |
|
|
|
if (!pools) |
|
return NULL; |
|
|
|
switch (type) { |
|
case DM_TYPE_BIO_BASED: |
|
case DM_TYPE_DAX_BIO_BASED: |
|
pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size); |
|
front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + DM_TARGET_IO_BIO_OFFSET; |
|
io_front_pad = roundup(per_io_data_size, __alignof__(struct dm_io)) + DM_IO_BIO_OFFSET; |
|
ret = bioset_init(&pools->io_bs, pool_size, io_front_pad, 0); |
|
if (ret) |
|
goto out; |
|
if (integrity && bioset_integrity_create(&pools->io_bs, pool_size)) |
|
goto out; |
|
break; |
|
case DM_TYPE_REQUEST_BASED: |
|
pool_size = max(dm_get_reserved_rq_based_ios(), min_pool_size); |
|
front_pad = offsetof(struct dm_rq_clone_bio_info, clone); |
|
/* per_io_data_size is used for blk-mq pdu at queue allocation */ |
|
break; |
|
default: |
|
BUG(); |
|
} |
|
|
|
ret = bioset_init(&pools->bs, pool_size, front_pad, 0); |
|
if (ret) |
|
goto out; |
|
|
|
if (integrity && bioset_integrity_create(&pools->bs, pool_size)) |
|
goto out; |
|
|
|
return pools; |
|
|
|
out: |
|
dm_free_md_mempools(pools); |
|
|
|
return NULL; |
|
} |
|
|
|
void dm_free_md_mempools(struct dm_md_mempools *pools) |
|
{ |
|
if (!pools) |
|
return; |
|
|
|
bioset_exit(&pools->bs); |
|
bioset_exit(&pools->io_bs); |
|
|
|
kfree(pools); |
|
} |
|
|
|
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; |
|
struct dm_table *table; |
|
struct dm_target *ti; |
|
int ret = -ENOTTY, srcu_idx; |
|
|
|
table = dm_get_live_table(md, &srcu_idx); |
|
if (!table || !dm_table_get_size(table)) |
|
goto out; |
|
|
|
/* 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); |
|
|
|
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, |
|
u32 flags) |
|
{ |
|
struct mapped_device *md = bdev->bd_disk->private_data; |
|
const struct pr_ops *ops; |
|
int r, srcu_idx; |
|
|
|
r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
|
if (r < 0) |
|
goto out; |
|
|
|
ops = bdev->bd_disk->fops->pr_ops; |
|
if (ops && ops->pr_reserve) |
|
r = ops->pr_reserve(bdev, key, type, flags); |
|
else |
|
r = -EOPNOTSUPP; |
|
out: |
|
dm_unprepare_ioctl(md, srcu_idx); |
|
return r; |
|
} |
|
|
|
static int dm_pr_release(struct block_device *bdev, u64 key, enum pr_type type) |
|
{ |
|
struct mapped_device *md = bdev->bd_disk->private_data; |
|
const struct pr_ops *ops; |
|
int r, srcu_idx; |
|
|
|
r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
|
if (r < 0) |
|
goto out; |
|
|
|
ops = bdev->bd_disk->fops->pr_ops; |
|
if (ops && ops->pr_release) |
|
r = ops->pr_release(bdev, key, type); |
|
else |
|
r = -EOPNOTSUPP; |
|
out: |
|
dm_unprepare_ioctl(md, srcu_idx); |
|
return r; |
|
} |
|
|
|
static int dm_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key, |
|
enum pr_type type, bool abort) |
|
{ |
|
struct mapped_device *md = bdev->bd_disk->private_data; |
|
const struct pr_ops *ops; |
|
int r, srcu_idx; |
|
|
|
r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
|
if (r < 0) |
|
goto out; |
|
|
|
ops = bdev->bd_disk->fops->pr_ops; |
|
if (ops && ops->pr_preempt) |
|
r = ops->pr_preempt(bdev, old_key, new_key, type, abort); |
|
else |
|
r = -EOPNOTSUPP; |
|
out: |
|
dm_unprepare_ioctl(md, srcu_idx); |
|
return r; |
|
} |
|
|
|
static int dm_pr_clear(struct block_device *bdev, u64 key) |
|
{ |
|
struct mapped_device *md = bdev->bd_disk->private_data; |
|
const struct pr_ops *ops; |
|
int r, srcu_idx; |
|
|
|
r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
|
if (r < 0) |
|
goto out; |
|
|
|
ops = bdev->bd_disk->fops->pr_ops; |
|
if (ops && ops->pr_clear) |
|
r = ops->pr_clear(bdev, key); |
|
else |
|
r = -EOPNOTSUPP; |
|
out: |
|
dm_unprepare_ioctl(md, srcu_idx); |
|
return r; |
|
} |
|
|
|
static const struct pr_ops dm_pr_ops = { |
|
.pr_register = dm_pr_register, |
|
.pr_reserve = dm_pr_reserve, |
|
.pr_release = dm_pr_release, |
|
.pr_preempt = dm_pr_preempt, |
|
.pr_clear = dm_pr_clear, |
|
}; |
|
|
|
static const struct block_device_operations dm_blk_dops = { |
|
.submit_bio = dm_submit_bio, |
|
.open = dm_blk_open, |
|
.release = dm_blk_close, |
|
.ioctl = dm_blk_ioctl, |
|
.getgeo = dm_blk_getgeo, |
|
.report_zones = dm_blk_report_zones, |
|
.pr_ops = &dm_pr_ops, |
|
.owner = THIS_MODULE |
|
}; |
|
|
|
static const struct block_device_operations dm_rq_blk_dops = { |
|
.open = dm_blk_open, |
|
.release = dm_blk_close, |
|
.ioctl = dm_blk_ioctl, |
|
.getgeo = dm_blk_getgeo, |
|
.pr_ops = &dm_pr_ops, |
|
.owner = THIS_MODULE |
|
}; |
|
|
|
static const struct dax_operations dm_dax_ops = { |
|
.direct_access = dm_dax_direct_access, |
|
.dax_supported = dm_dax_supported, |
|
.copy_from_iter = dm_dax_copy_from_iter, |
|
.copy_to_iter = dm_dax_copy_to_iter, |
|
.zero_page_range = dm_dax_zero_page_range, |
|
}; |
|
|
|
/* |
|
* module hooks |
|
*/ |
|
module_init(dm_init); |
|
module_exit(dm_exit); |
|
|
|
module_param(major, uint, 0); |
|
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(dm_numa_node, int, S_IRUGO | S_IWUSR); |
|
MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations"); |
|
|
|
module_param(swap_bios, int, S_IRUGO | S_IWUSR); |
|
MODULE_PARM_DESC(swap_bios, "Maximum allowed inflight swap IOs"); |
|
|
|
MODULE_DESCRIPTION(DM_NAME " driver"); |
|
MODULE_AUTHOR("Joe Thornber <[email protected]>"); |
|
MODULE_LICENSE("GPL");
|
|
|