diff options
author | Dan Williams <dan.j.williams@intel.com> | 2016-12-17 23:50:04 +0100 |
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committer | Dan Williams <dan.j.williams@intel.com> | 2016-12-17 23:50:04 +0100 |
commit | d7fe1a67f658b50ec98ee1afb86df7b35c2b2593 (patch) | |
tree | 2831af61dca813ce22e362528adee7d037d0c80f /drivers/dax/dax.c | |
parent | libnvdimm: fix mishandled nvdimm_clear_poison() return value (diff) | |
download | linux-d7fe1a67f658b50ec98ee1afb86df7b35c2b2593.tar.xz linux-d7fe1a67f658b50ec98ee1afb86df7b35c2b2593.zip |
dax: add region 'id', 'size', and 'align' attributes
While this information is available by looking at the nvdimm parent
device that may not always be the case when/if we add support for other
memory regions. Tooling should not depend on walking a given ancestor
topology that is not guaranteed by the device's class. For example, a
device-dax instance will always have a dax_region parent, but it may not
always have a libnvdimm "dax" device as a grandparent.
Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dax/dax.c')
-rw-r--r-- | drivers/dax/dax.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c index 0e499bfca41c..369fccda3b1b 100644 --- a/drivers/dax/dax.c +++ b/drivers/dax/dax.c @@ -75,6 +75,73 @@ struct dax_dev { struct resource res[0]; }; +static ssize_t id_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dax_region *dax_region; + ssize_t rc = -ENXIO; + + device_lock(dev); + dax_region = dev_get_drvdata(dev); + if (dax_region) + rc = sprintf(buf, "%d\n", dax_region->id); + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RO(id); + +static ssize_t region_size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dax_region *dax_region; + ssize_t rc = -ENXIO; + + device_lock(dev); + dax_region = dev_get_drvdata(dev); + if (dax_region) + rc = sprintf(buf, "%llu\n", (unsigned long long) + resource_size(&dax_region->res)); + device_unlock(dev); + + return rc; +} +static struct device_attribute dev_attr_region_size = __ATTR(size, 0444, + region_size_show, NULL); + +static ssize_t align_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dax_region *dax_region; + ssize_t rc = -ENXIO; + + device_lock(dev); + dax_region = dev_get_drvdata(dev); + if (dax_region) + rc = sprintf(buf, "%u\n", dax_region->align); + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RO(align); + +static struct attribute *dax_region_attributes[] = { + &dev_attr_region_size.attr, + &dev_attr_align.attr, + &dev_attr_id.attr, + NULL, +}; + +static const struct attribute_group dax_region_attribute_group = { + .name = "dax_region", + .attrs = dax_region_attributes, +}; + +static const struct attribute_group *dax_region_attribute_groups[] = { + &dax_region_attribute_group, + NULL, +}; + static struct inode *dax_alloc_inode(struct super_block *sb) { return kmem_cache_alloc(dax_cache, GFP_KERNEL); @@ -200,12 +267,31 @@ void dax_region_put(struct dax_region *dax_region) } EXPORT_SYMBOL_GPL(dax_region_put); +static void dax_region_unregister(void *region) +{ + struct dax_region *dax_region = region; + + sysfs_remove_groups(&dax_region->dev->kobj, + dax_region_attribute_groups); + dax_region_put(dax_region); +} + struct dax_region *alloc_dax_region(struct device *parent, int region_id, struct resource *res, unsigned int align, void *addr, unsigned long pfn_flags) { struct dax_region *dax_region; + /* + * The DAX core assumes that it can store its private data in + * parent->driver_data. This WARN is a reminder / safeguard for + * developers of device-dax drivers. + */ + if (dev_get_drvdata(parent)) { + dev_WARN(parent, "dax core failed to setup private data\n"); + return NULL; + } + if (!IS_ALIGNED(res->start, align) || !IS_ALIGNED(resource_size(res), align)) return NULL; @@ -214,6 +300,7 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, if (!dax_region) return NULL; + dev_set_drvdata(parent, dax_region); memcpy(&dax_region->res, res, sizeof(*res)); dax_region->pfn_flags = pfn_flags; kref_init(&dax_region->kref); @@ -222,7 +309,14 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, dax_region->align = align; dax_region->dev = parent; dax_region->base = addr; + if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) { + kfree(dax_region); + return NULL;; + } + kref_get(&dax_region->kref); + if (devm_add_action_or_reset(parent, dax_region_unregister, dax_region)) + return NULL; return dax_region; } EXPORT_SYMBOL_GPL(alloc_dax_region); |