Revision 3e1a0699095803e53072699a4a1485af7744601d authored by Joe Thornber on 03 March 2014, 16:03:26 UTC, committed by Mike Snitzer on 05 March 2014, 20:26:58 UTC
Ideally a thin pool would never run out of data space; the low water mark would trigger userland to extend the pool before we completely run out of space. However, many small random IOs to unprovisioned space can consume data space at an alarming rate. Adjust your low water mark if you're frequently seeing "out-of-data-space" mode. Before this fix, if data space ran out the pool would be put in PM_READ_ONLY mode which also aborted the pool's current metadata transaction (data loss for any changes in the transaction). This had a side-effect of needlessly compromising data consistency. And retry of queued unserviceable bios, once the data pool was resized, could initiate changes to potentially inconsistent pool metadata. Now when the pool's data space is exhausted transition to a new pool mode (PM_OUT_OF_DATA_SPACE) that allows metadata to be changed but data may not be allocated. This allows users to remove thin volumes or discard data to recover data space. The pool is no longer put in PM_READ_ONLY mode in response to the pool running out of data space. And PM_READ_ONLY mode no longer aborts the pool's current metadata transaction. Also, set_pool_mode() will now notify userspace when the pool mode is changed. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
1 parent 07f2b6e
dummy.c
/*
* dummy.c
*
* Copyright 2010 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This is useful for systems with mixed controllable and
* non-controllable regulators, as well as for allowing testing on
* systems with no controllable regulators.
*/
#include <linux/err.h>
#include <linux/export.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include "dummy.h"
struct regulator_dev *dummy_regulator_rdev;
static struct regulator_init_data dummy_initdata;
static struct regulator_ops dummy_ops;
static struct regulator_desc dummy_desc = {
.name = "regulator-dummy",
.id = -1,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.ops = &dummy_ops,
};
static int dummy_regulator_probe(struct platform_device *pdev)
{
struct regulator_config config = { };
int ret;
config.dev = &pdev->dev;
config.init_data = &dummy_initdata;
dummy_regulator_rdev = regulator_register(&dummy_desc, &config);
if (IS_ERR(dummy_regulator_rdev)) {
ret = PTR_ERR(dummy_regulator_rdev);
pr_err("Failed to register regulator: %d\n", ret);
return ret;
}
return 0;
}
static struct platform_driver dummy_regulator_driver = {
.probe = dummy_regulator_probe,
.driver = {
.name = "reg-dummy",
.owner = THIS_MODULE,
},
};
static struct platform_device *dummy_pdev;
void __init regulator_dummy_init(void)
{
int ret;
dummy_pdev = platform_device_alloc("reg-dummy", -1);
if (!dummy_pdev) {
pr_err("Failed to allocate dummy regulator device\n");
return;
}
ret = platform_device_add(dummy_pdev);
if (ret != 0) {
pr_err("Failed to register dummy regulator device: %d\n", ret);
platform_device_put(dummy_pdev);
return;
}
ret = platform_driver_register(&dummy_regulator_driver);
if (ret != 0) {
pr_err("Failed to register dummy regulator driver: %d\n", ret);
platform_device_unregister(dummy_pdev);
}
}
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...