OpenE2K/linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

Browse Source 
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm kcopyd: return client directly and not through a pointer
  dm kcopyd: reserve fewer pages
  dm io: use fixed initial mempool size
  dm kcopyd: alloc pages from the main page allocator
  dm kcopyd: add gfp parm to alloc_pl
  dm kcopyd: remove superfluous page allocation spinlock
  dm kcopyd: preallocate sub jobs to avoid deadlock
  dm kcopyd: avoid pointless job splitting
  dm mpath: do not fail paths after integrity errors
  dm table: reject devices without request fns
  dm table: allow targets to support discards internally
This commit is contained in:
Linus Torvalds 2011-05-29 11:20:48 -07:00
commit b11b06d90a
11 changed files with 144 additions and 124 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
drivers/md/dm-io.c
View File

@ -19,6 +19,8 @@
#define DM_MSG_PREFIX "io"
#define DM_IO_MAX_REGIONS BITS_PER_LONG
#define MIN_IOS 16
#define MIN_BIOS 16
struct dm_io_client {
mempool_t *pool;
@ -40,34 +42,22 @@ struct io {
static struct kmem_cache *_dm_io_cache;
/*
* io contexts are only dynamically allocated for asynchronous
* io. Since async io is likely to be the majority of io we'll
* have the same number of io contexts as bios! (FIXME: must reduce this).
*/
static unsigned int pages_to_ios(unsigned int pages)
{
return 4 * pages; /* too many ? */
}
/*
* Create a client with mempool and bioset.
*/
struct dm_io_client *dm_io_client_create(unsigned num_pages)
struct dm_io_client *dm_io_client_create(void)
{
unsigned ios = pages_to_ios(num_pages);
struct dm_io_client *client;
client = kmalloc(sizeof(*client), GFP_KERNEL);
if (!client)
return ERR_PTR(-ENOMEM);
client->pool = mempool_create_slab_pool(ios, _dm_io_cache);
client->pool = mempool_create_slab_pool(MIN_IOS, _dm_io_cache);
if (!client->pool)
goto bad;
client->bios = bioset_create(16, 0);
client->bios = bioset_create(MIN_BIOS, 0);
if (!client->bios)
goto bad;
@ -81,13 +71,6 @@ struct dm_io_client *dm_io_client_create(unsigned num_pages)
}
EXPORT_SYMBOL(dm_io_client_create);
int dm_io_client_resize(unsigned num_pages, struct dm_io_client *client)
{
return mempool_resize(client->pool, pages_to_ios(num_pages),
GFP_KERNEL);
}
EXPORT_SYMBOL(dm_io_client_resize);
void dm_io_client_destroy(struct dm_io_client *client)
{
mempool_destroy(client->pool);

168
drivers/md/dm-kcopyd.c
View File

@ -27,15 +27,19 @@
#include "dm.h"
#define SUB_JOB_SIZE 128
#define SPLIT_COUNT 8
#define MIN_JOBS 8
#define RESERVE_PAGES (DIV_ROUND_UP(SUB_JOB_SIZE << SECTOR_SHIFT, PAGE_SIZE))
/*-----------------------------------------------------------------
* Each kcopyd client has its own little pool of preallocated
* pages for kcopyd io.
*---------------------------------------------------------------*/
struct dm_kcopyd_client {
spinlock_t lock;
struct page_list *pages;
unsigned int nr_pages;
unsigned int nr_free_pages;
unsigned nr_reserved_pages;
unsigned nr_free_pages;
struct dm_io_client *io_client;
@ -67,15 +71,18 @@ static void wake(struct dm_kcopyd_client *kc)
queue_work(kc->kcopyd_wq, &kc->kcopyd_work);
}
static struct page_list *alloc_pl(void)
/*
* Obtain one page for the use of kcopyd.
*/
static struct page_list *alloc_pl(gfp_t gfp)
{
struct page_list *pl;
pl = kmalloc(sizeof(*pl), GFP_KERNEL);
pl = kmalloc(sizeof(*pl), gfp);
if (!pl)
return NULL;
pl->page = alloc_page(GFP_KERNEL);
pl->page = alloc_page(gfp);
if (!pl->page) {
kfree(pl);
return NULL;
@ -90,41 +97,56 @@ static void free_pl(struct page_list *pl)
kfree(pl);
}
/*
* Add the provided pages to a client's free page list, releasing
* back to the system any beyond the reserved_pages limit.
*/
static void kcopyd_put_pages(struct dm_kcopyd_client *kc, struct page_list *pl)
{
struct page_list *next;
do {
next = pl->next;
if (kc->nr_free_pages >= kc->nr_reserved_pages)
free_pl(pl);
else {
pl->next = kc->pages;
kc->pages = pl;
kc->nr_free_pages++;
}
pl = next;
} while (pl);
}
static int kcopyd_get_pages(struct dm_kcopyd_client *kc,
unsigned int nr, struct page_list **pages)
{
struct page_list *pl;
spin_lock(&kc->lock);
if (kc->nr_free_pages < nr) {
spin_unlock(&kc->lock);
return -ENOMEM;
}
*pages = NULL;
kc->nr_free_pages -= nr;
for (*pages = pl = kc->pages; --nr; pl = pl->next)
;
kc->pages = pl->next;
pl->next = NULL;
spin_unlock(&kc->lock);
do {
pl = alloc_pl(__GFP_NOWARN | __GFP_NORETRY);
if (unlikely(!pl)) {
/* Use reserved pages */
pl = kc->pages;
if (unlikely(!pl))
goto out_of_memory;
kc->pages = pl->next;
kc->nr_free_pages--;
}
pl->next = *pages;
*pages = pl;
} while (--nr);
return 0;
}
static void kcopyd_put_pages(struct dm_kcopyd_client *kc, struct page_list *pl)
{
struct page_list *cursor;
spin_lock(&kc->lock);
for (cursor = pl; cursor->next; cursor = cursor->next)
kc->nr_free_pages++;
kc->nr_free_pages++;
cursor->next = kc->pages;
kc->pages = pl;
spin_unlock(&kc->lock);
out_of_memory:
if (*pages)
kcopyd_put_pages(kc, *pages);
return -ENOMEM;
}
/*
@ -141,13 +163,16 @@ static void drop_pages(struct page_list *pl)
}
}
static int client_alloc_pages(struct dm_kcopyd_client *kc, unsigned int nr)
/*
* Allocate and reserve nr_pages for the use of a specific client.
*/
static int client_reserve_pages(struct dm_kcopyd_client *kc, unsigned nr_pages)
{
unsigned int i;
unsigned i;
struct page_list *pl = NULL, *next;
for (i = 0; i < nr; i++) {
next = alloc_pl();
for (i = 0; i < nr_pages; i++) {
next = alloc_pl(GFP_KERNEL);
if (!next) {
if (pl)
drop_pages(pl);
@ -157,17 +182,18 @@ static int client_alloc_pages(struct dm_kcopyd_client *kc, unsigned int nr)
pl = next;
}
kc->nr_reserved_pages += nr_pages;
kcopyd_put_pages(kc, pl);
kc->nr_pages += nr;
return 0;
}
static void client_free_pages(struct dm_kcopyd_client *kc)
{
BUG_ON(kc->nr_free_pages != kc->nr_pages);
BUG_ON(kc->nr_free_pages != kc->nr_reserved_pages);
drop_pages(kc->pages);
kc->pages = NULL;
kc->nr_free_pages = kc->nr_pages = 0;
kc->nr_free_pages = kc->nr_reserved_pages = 0;
}
/*-----------------------------------------------------------------
@ -216,16 +242,17 @@ struct kcopyd_job {
struct mutex lock;
atomic_t sub_jobs;
sector_t progress;
};
/* FIXME: this should scale with the number of pages */
#define MIN_JOBS 512
struct kcopyd_job *master_job;
};
static struct kmem_cache *_job_cache;
int __init dm_kcopyd_init(void)
{
_job_cache = KMEM_CACHE(kcopyd_job, 0);
_job_cache = kmem_cache_create("kcopyd_job",
sizeof(struct kcopyd_job) * (SPLIT_COUNT + 1),
__alignof__(struct kcopyd_job), 0, NULL);
if (!_job_cache)
return -ENOMEM;
@ -299,7 +326,12 @@ static int run_complete_job(struct kcopyd_job *job)
if (job->pages)
kcopyd_put_pages(kc, job->pages);
mempool_free(job, kc->job_pool);
/*
* If this is the master job, the sub jobs have already
* completed so we can free everything.
*/
if (job->master_job == job)
mempool_free(job, kc->job_pool);
fn(read_err, write_err, context);
if (atomic_dec_and_test(&kc->nr_jobs))
@ -460,14 +492,14 @@ static void dispatch_job(struct kcopyd_job *job)
wake(kc);
}
#define SUB_JOB_SIZE 128
static void segment_complete(int read_err, unsigned long write_err,
void *context)
{
/* FIXME: tidy this function */
sector_t progress = 0;
sector_t count = 0;
struct kcopyd_job *job = (struct kcopyd_job *) context;
struct kcopyd_job *sub_job = (struct kcopyd_job *) context;
struct kcopyd_job *job = sub_job->master_job;
struct dm_kcopyd_client *kc = job->kc;
mutex_lock(&job->lock);
@ -498,8 +530,6 @@ static void segment_complete(int read_err, unsigned long write_err,
if (count) {
int i;
struct kcopyd_job *sub_job = mempool_alloc(kc->job_pool,
GFP_NOIO);
*sub_job = *job;
sub_job->source.sector += progress;
@ -511,7 +541,7 @@ static void segment_complete(int read_err, unsigned long write_err,
}
sub_job->fn = segment_complete;
sub_job->context = job;
sub_job->context = sub_job;
dispatch_job(sub_job);
} else if (atomic_dec_and_test(&job->sub_jobs)) {
@ -531,19 +561,19 @@ static void segment_complete(int read_err, unsigned long write_err,
}
/*
* Create some little jobs that will do the move between
* them.
* Create some sub jobs to share the work between them.
*/
#define SPLIT_COUNT 8
static void split_job(struct kcopyd_job *job)
static void split_job(struct kcopyd_job *master_job)
{
int i;
atomic_inc(&job->kc->nr_jobs);
atomic_inc(&master_job->kc->nr_jobs);
atomic_set(&job->sub_jobs, SPLIT_COUNT);
for (i = 0; i < SPLIT_COUNT; i++)
segment_complete(0, 0u, job);
atomic_set(&master_job->sub_jobs, SPLIT_COUNT);
for (i = 0; i < SPLIT_COUNT; i++) {
master_job[i + 1].master_job = master_job;
segment_complete(0, 0u, &master_job[i + 1]);
}
}
int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
@ -553,7 +583,8 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
struct kcopyd_job *job;
/*
* Allocate a new job.
* Allocate an array of jobs consisting of one master job
* followed by SPLIT_COUNT sub jobs.
*/
job = mempool_alloc(kc->job_pool, GFP_NOIO);
@ -577,10 +608,10 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
job->fn = fn;
job->context = context;
job->master_job = job;
if (job->source.count < SUB_JOB_SIZE)
if (job->source.count <= SUB_JOB_SIZE)
dispatch_job(job);
else {
mutex_init(&job->lock);
job->progress = 0;
@ -606,17 +637,15 @@ int kcopyd_cancel(struct kcopyd_job *job, int block)
/*-----------------------------------------------------------------
* Client setup
*---------------------------------------------------------------*/
int dm_kcopyd_client_create(unsigned int nr_pages,
struct dm_kcopyd_client **result)
struct dm_kcopyd_client *dm_kcopyd_client_create(void)
{
int r = -ENOMEM;
struct dm_kcopyd_client *kc;
kc = kmalloc(sizeof(*kc), GFP_KERNEL);
if (!kc)
return -ENOMEM;
return ERR_PTR(-ENOMEM);
spin_lock_init(&kc->lock);
spin_lock_init(&kc->job_lock);
INIT_LIST_HEAD(&kc->complete_jobs);
INIT_LIST_HEAD(&kc->io_jobs);
@ -633,12 +662,12 @@ int dm_kcopyd_client_create(unsigned int nr_pages,
goto bad_workqueue;
kc->pages = NULL;
kc->nr_pages = kc->nr_free_pages = 0;
r = client_alloc_pages(kc, nr_pages);
kc->nr_reserved_pages = kc->nr_free_pages = 0;
r = client_reserve_pages(kc, RESERVE_PAGES);
if (r)
goto bad_client_pages;
kc->io_client = dm_io_client_create(nr_pages);
kc->io_client = dm_io_client_create();
if (IS_ERR(kc->io_client)) {
r = PTR_ERR(kc->io_client);
goto bad_io_client;
@ -647,8 +676,7 @@ int dm_kcopyd_client_create(unsigned int nr_pages,
init_waitqueue_head(&kc->destroyq);
atomic_set(&kc->nr_jobs, 0);
*result = kc;
return 0;
return kc;
bad_io_client:
client_free_pages(kc);
@ -659,7 +687,7 @@ bad_workqueue:
bad_slab:
kfree(kc);
return r;
return ERR_PTR(r);
}
EXPORT_SYMBOL(dm_kcopyd_client_create);

3
drivers/md/dm-log.c
View File

@ -449,8 +449,7 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
lc->io_req.mem.type = DM_IO_VMA;
lc->io_req.notify.fn = NULL;
lc->io_req.client = dm_io_client_create(dm_div_up(buf_size,
PAGE_SIZE));
lc->io_req.client = dm_io_client_create();
if (IS_ERR(lc->io_req.client)) {
r = PTR_ERR(lc->io_req.client);
DMWARN("couldn't allocate disk io client");

2
drivers/md/dm-mpath.c
View File

@ -1290,7 +1290,7 @@ static int do_end_io(struct multipath *m, struct request *clone,
if (!error && !clone->errors)
return 0; /* I/O complete */
if (error == -EOPNOTSUPP || error == -EREMOTEIO)
if (error == -EOPNOTSUPP || error == -EREMOTEIO || error == -EILSEQ)
return error;
if (mpio->pgpath)

10
drivers/md/dm-raid1.c
View File

@ -22,8 +22,6 @@
#define DM_MSG_PREFIX "raid1"
#define MAX_RECOVERY 1 /* Maximum number of regions recovered in parallel. */
#define DM_IO_PAGES 64
#define DM_KCOPYD_PAGES 64
#define DM_RAID1_HANDLE_ERRORS 0x01
#define errors_handled(p) ((p)->features & DM_RAID1_HANDLE_ERRORS)
@ -887,7 +885,7 @@ static struct mirror_set *alloc_context(unsigned int nr_mirrors,
return NULL;
}
ms->io_client = dm_io_client_create(DM_IO_PAGES);
ms->io_client = dm_io_client_create();
if (IS_ERR(ms->io_client)) {
ti->error = "Error creating dm_io client";
mempool_destroy(ms->read_record_pool);
@ -1117,9 +1115,11 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto err_destroy_wq;
}
r = dm_kcopyd_client_create(DM_KCOPYD_PAGES, &ms->kcopyd_client);
if (r)
ms->kcopyd_client = dm_kcopyd_client_create();
if (IS_ERR(ms->kcopyd_client)) {
r = PTR_ERR(ms->kcopyd_client);
goto err_destroy_wq;
}
wakeup_mirrord(ms);
return 0;

13
drivers/md/dm-snap-persistent.c
View File

@ -154,11 +154,6 @@ struct pstore {
struct workqueue_struct *metadata_wq;
};
static unsigned sectors_to_pages(unsigned sectors)
{
return DIV_ROUND_UP(sectors, PAGE_SIZE >> 9);
}
static int alloc_area(struct pstore *ps)
{
int r = -ENOMEM;
@ -318,8 +313,7 @@ static int read_header(struct pstore *ps, int *new_snapshot)
chunk_size_supplied = 0;
}
ps->io_client = dm_io_client_create(sectors_to_pages(ps->store->
chunk_size));
ps->io_client = dm_io_client_create();
if (IS_ERR(ps->io_client))
return PTR_ERR(ps->io_client);
@ -368,11 +362,6 @@ static int read_header(struct pstore *ps, int *new_snapshot)
return r;
}
r = dm_io_client_resize(sectors_to_pages(ps->store->chunk_size),
ps->io_client);
if (r)
return r;
r = alloc_area(ps);
return r;

10
drivers/md/dm-snap.c
View File

@ -39,11 +39,6 @@ static const char dm_snapshot_merge_target_name[] = "snapshot-merge";
*/
#define SNAPSHOT_COPY_PRIORITY 2
/*
* Reserve 1MB for each snapshot initially (with minimum of 1 page).
*/
#define SNAPSHOT_PAGES (((1UL << 20) >> PAGE_SHIFT) ? : 1)
/*
* The size of the mempool used to track chunks in use.
*/
@ -1116,8 +1111,9 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto bad_hash_tables;
}
r = dm_kcopyd_client_create(SNAPSHOT_PAGES, &s->kcopyd_client);
if (r) {
s->kcopyd_client = dm_kcopyd_client_create();
if (IS_ERR(s->kcopyd_client)) {
r = PTR_ERR(s->kcopyd_client);
ti->error = "Could not create kcopyd client";
goto bad_kcopyd;
}

23
drivers/md/dm-table.c
View File

@ -362,6 +362,7 @@ static void close_dev(struct dm_dev_internal *d, struct mapped_device *md)
static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
{
struct request_queue *q;
struct queue_limits *limits = data;
struct block_device *bdev = dev->bdev;
sector_t dev_size =
@ -370,6 +371,22 @@ static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
limits->logical_block_size >> SECTOR_SHIFT;
char b[BDEVNAME_SIZE];
/*
* Some devices exist without request functions,
* such as loop devices not yet bound to backing files.
* Forbid the use of such devices.
*/
q = bdev_get_queue(bdev);
if (!q || !q->make_request_fn) {
DMWARN("%s: %s is not yet initialised: "
"start=%llu, len=%llu, dev_size=%llu",
dm_device_name(ti->table->md), bdevname(bdev, b),
(unsigned long long)start,
(unsigned long long)len,
(unsigned long long)dev_size);
return 1;
}
if (!dev_size)
return 0;
@ -1346,7 +1363,8 @@ bool dm_table_supports_discards(struct dm_table *t)
return 0;
/*
* Ensure that at least one underlying device supports discards.
* Unless any target used by the table set discards_supported,
* require at least one underlying device to support discards.
* t->devices includes internal dm devices such as mirror logs
* so we need to use iterate_devices here, which targets
* supporting discard must provide.
@ -1354,6 +1372,9 @@ bool dm_table_supports_discards(struct dm_table *t)
while (i < dm_table_get_num_targets(t)) {
ti = dm_table_get_target(t, i++);
if (ti->discards_supported)
return 1;
if (ti->type->iterate_devices &&
ti->type->iterate_devices(ti, device_discard_capable, NULL))
return 1;

6
include/linux/device-mapper.h
View File

@ -191,6 +191,12 @@ struct dm_target {
/* Used to provide an error string from the ctr */
char *error;
/*
* Set if this target needs to receive discards regardless of
* whether or not its underlying devices have support.
*/
unsigned discards_supported:1;
};
/* Each target can link one of these into the table */

3
include/linux/dm-io.h
View File

@ -69,8 +69,7 @@ struct dm_io_request {
*
* Create/destroy may block.
*/
struct dm_io_client *dm_io_client_create(unsigned num_pages);
int dm_io_client_resize(unsigned num_pages, struct dm_io_client *client);
struct dm_io_client *dm_io_client_create(void);
void dm_io_client_destroy(struct dm_io_client *client);
/*

3
include/linux/dm-kcopyd.h
View File

@ -25,8 +25,7 @@
* To use kcopyd you must first create a dm_kcopyd_client object.
*/
struct dm_kcopyd_client;
int dm_kcopyd_client_create(unsigned num_pages,
struct dm_kcopyd_client **result);
struct dm_kcopyd_client *dm_kcopyd_client_create(void);
void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc);
/*