dm thin: commit before gathering status

Commit outstanding metadata before returning the status for a dm thin
pool so that the numbers reported are as up-to-date as possible.

The commit is not performed if the device is suspended or if
the DM_NOFLUSH_FLAG is supplied by userspace and passed to the target
through a new 'status_flags' parameter in the target's dm_status_fn.

The userspace dmsetup tool will support the --noflush flag with the
'dmsetup status' and 'dmsetup wait' commands from version 1.02.76
onwards.

Tested-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Alasdair G Kergon 2012-07-27 15:08:16 +01:00
parent e49e582965
commit 1f4e0ff079
15 changed files with 35 additions and 20 deletions

View File

@ -1733,7 +1733,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
}
static int crypt_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
struct crypt_config *cc = ti->private;
unsigned int sz = 0;

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@ -295,7 +295,7 @@ static int delay_map(struct dm_target *ti, struct bio *bio,
}
static int delay_status(struct dm_target *ti, status_type_t type,
char *result, unsigned maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
struct delay_c *dc = ti->private;
int sz = 0;

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@ -333,7 +333,7 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio,
}
static int flakey_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
unsigned sz = 0;
struct flakey_c *fc = ti->private;

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@ -1054,6 +1054,7 @@ static void retrieve_status(struct dm_table *table,
char *outbuf, *outptr;
status_type_t type;
size_t remaining, len, used = 0;
unsigned status_flags = 0;
outptr = outbuf = get_result_buffer(param, param_size, &len);
@ -1090,7 +1091,9 @@ static void retrieve_status(struct dm_table *table,
/* Get the status/table string from the target driver */
if (ti->type->status) {
if (ti->type->status(ti, type, outptr, remaining)) {
if (param->flags & DM_NOFLUSH_FLAG)
status_flags |= DM_STATUS_NOFLUSH_FLAG;
if (ti->type->status(ti, type, status_flags, outptr, remaining)) {
param->flags |= DM_BUFFER_FULL_FLAG;
break;
}

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@ -96,7 +96,7 @@ static int linear_map(struct dm_target *ti, struct bio *bio,
}
static int linear_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
struct linear_c *lc = (struct linear_c *) ti->private;

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@ -1378,7 +1378,7 @@ static void multipath_resume(struct dm_target *ti)
* num_paths num_selector_args [path_dev [selector_args]* ]+ ]+
*/
static int multipath_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
int sz = 0;
unsigned long flags;

View File

@ -1081,7 +1081,7 @@ static int raid_map(struct dm_target *ti, struct bio *bio, union map_info *map_c
}
static int raid_status(struct dm_target *ti, status_type_t type,
char *result, unsigned maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
struct raid_set *rs = ti->private;
unsigned raid_param_cnt = 1; /* at least 1 for chunksize */

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@ -1367,7 +1367,7 @@ static char device_status_char(struct mirror *m)
static int mirror_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
unsigned int m, sz = 0;
struct mirror_set *ms = (struct mirror_set *) ti->private;

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@ -1849,7 +1849,7 @@ static void snapshot_merge_resume(struct dm_target *ti)
}
static int snapshot_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
unsigned sz = 0;
struct dm_snapshot *snap = ti->private;
@ -2151,8 +2151,8 @@ static void origin_resume(struct dm_target *ti)
ti->max_io_len = get_origin_minimum_chunksize(dev->bdev);
}
static int origin_status(struct dm_target *ti, status_type_t type, char *result,
unsigned int maxlen)
static int origin_status(struct dm_target *ti, status_type_t type,
unsigned status_flags, char *result, unsigned maxlen)
{
struct dm_dev *dev = ti->private;

View File

@ -311,8 +311,8 @@ static int stripe_map(struct dm_target *ti, struct bio *bio,
*
*/
static int stripe_status(struct dm_target *ti,
status_type_t type, char *result, unsigned int maxlen)
static int stripe_status(struct dm_target *ti, status_type_t type,
unsigned status_flags, char *result, unsigned maxlen)
{
struct stripe_c *sc = (struct stripe_c *) ti->private;
char buffer[sc->stripes + 1];

View File

@ -5,6 +5,7 @@
*/
#include "dm-thin-metadata.h"
#include "dm.h"
#include <linux/device-mapper.h>
#include <linux/dm-io.h>
@ -2619,7 +2620,7 @@ static void emit_flags(struct pool_features *pf, char *result,
* <used data sectors>/<total data sectors> <held metadata root>
*/
static int pool_status(struct dm_target *ti, status_type_t type,
char *result, unsigned maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
int r;
unsigned sz = 0;
@ -2641,6 +2642,10 @@ static int pool_status(struct dm_target *ti, status_type_t type,
break;
}
/* Commit to ensure statistics aren't out-of-date */
if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti))
(void) commit_or_fallback(pool);
r = dm_pool_get_metadata_transaction_id(pool->pmd,
&transaction_id);
if (r)
@ -2968,7 +2973,7 @@ static void thin_postsuspend(struct dm_target *ti)
* <nr mapped sectors> <highest mapped sector>
*/
static int thin_status(struct dm_target *ti, status_type_t type,
char *result, unsigned maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
int r;
ssize_t sz = 0;

View File

@ -515,7 +515,7 @@ static int verity_map(struct dm_target *ti, struct bio *bio,
* Status: V (valid) or C (corruption found)
*/
static int verity_status(struct dm_target *ti, status_type_t type,
char *result, unsigned maxlen)
unsigned status_flags, char *result, unsigned maxlen)
{
struct dm_verity *v = ti->private;
unsigned sz = 0;

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@ -22,6 +22,11 @@
#define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
/*
* Status feature flags
*/
#define DM_STATUS_NOFLUSH_FLAG (1 << 0)
/*
* Type of table and mapped_device's mempool
*/

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@ -72,7 +72,7 @@ typedef int (*dm_preresume_fn) (struct dm_target *ti);
typedef void (*dm_resume_fn) (struct dm_target *ti);
typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
char *result, unsigned int maxlen);
unsigned status_flags, char *result, unsigned maxlen);
typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv);

View File

@ -267,9 +267,9 @@ enum {
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
#define DM_VERSION_MINOR 22
#define DM_VERSION_PATCHLEVEL 1
#define DM_VERSION_EXTRA "-ioctl (2012-06-01)"
#define DM_VERSION_MINOR 23
#define DM_VERSION_PATCHLEVEL 0
#define DM_VERSION_EXTRA "-ioctl (2012-07-25)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */
@ -307,6 +307,8 @@ enum {
/*
* Set this to suspend without flushing queued ios.
* Also disables flushing uncommitted changes in the thin target before
* generating statistics for DM_TABLE_STATUS and DM_DEV_WAIT.
*/
#define DM_NOFLUSH_FLAG (1 << 11) /* In */