diff options
Diffstat (limited to 'drivers/dax/bus.c')
| -rw-r--r-- | drivers/dax/bus.c | 465 |
1 files changed, 295 insertions, 170 deletions
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 5aee26e1bbd6..fde29e0ad68b 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -10,17 +10,27 @@ #include "dax-private.h" #include "bus.h" -static struct class *dax_class; - static DEFINE_MUTEX(dax_bus_lock); +/* + * All changes to the dax region configuration occur with this lock held + * for write. + */ +DECLARE_RWSEM(dax_region_rwsem); + +/* + * All changes to the dax device configuration occur with this lock held + * for write. + */ +DECLARE_RWSEM(dax_dev_rwsem); + #define DAX_NAME_LEN 30 struct dax_id { struct list_head list; char dev_name[DAX_NAME_LEN]; }; -static int dax_bus_uevent(struct device *dev, struct kobj_uevent_env *env) +static int dax_bus_uevent(const struct device *dev, struct kobj_uevent_env *env) { /* * We only ever expect to handle device-dax instances, i.e. the @@ -29,12 +39,9 @@ static int dax_bus_uevent(struct device *dev, struct kobj_uevent_env *env) return add_uevent_var(env, "MODALIAS=" DAX_DEVICE_MODALIAS_FMT, 0); } -static struct dax_device_driver *to_dax_drv(struct device_driver *drv) -{ - return container_of(drv, struct dax_device_driver, drv); -} +#define to_dax_drv(__drv) container_of_const(__drv, struct dax_device_driver, drv) -static struct dax_id *__dax_match_id(struct dax_device_driver *dax_drv, +static struct dax_id *__dax_match_id(const struct dax_device_driver *dax_drv, const char *dev_name) { struct dax_id *dax_id; @@ -47,7 +54,7 @@ static struct dax_id *__dax_match_id(struct dax_device_driver *dax_drv, return NULL; } -static int dax_match_id(struct dax_device_driver *dax_drv, struct device *dev) +static int dax_match_id(const struct dax_device_driver *dax_drv, struct device *dev) { int match; @@ -58,6 +65,25 @@ static int dax_match_id(struct dax_device_driver *dax_drv, struct device *dev) return match; } +static int dax_match_type(const struct dax_device_driver *dax_drv, struct device *dev) +{ + enum dax_driver_type type = DAXDRV_DEVICE_TYPE; + struct dev_dax *dev_dax = to_dev_dax(dev); + + if (dev_dax->region->res.flags & IORESOURCE_DAX_KMEM) + type = DAXDRV_KMEM_TYPE; + + if (dax_drv->type == type) + return 1; + + /* default to device mode if dax_kmem is disabled */ + if (dax_drv->type == DAXDRV_DEVICE_TYPE && + !IS_ENABLED(CONFIG_DEV_DAX_KMEM)) + return 1; + + return 0; +} + enum id_action { ID_REMOVE, ID_ADD, @@ -86,7 +112,7 @@ static ssize_t do_id_store(struct device_driver *drv, const char *buf, if (action == ID_ADD) { dax_id = kzalloc(sizeof(*dax_id), GFP_KERNEL); if (dax_id) { - strncpy(dax_id->dev_name, buf, DAX_NAME_LEN); + strscpy(dax_id->dev_name, buf, DAX_NAME_LEN); list_add(&dax_id->list, &dax_drv->ids); } else rc = -ENOMEM; @@ -127,19 +153,43 @@ static struct attribute *dax_drv_attrs[] = { }; ATTRIBUTE_GROUPS(dax_drv); -static int dax_bus_match(struct device *dev, struct device_driver *drv); +static int dax_bus_match(struct device *dev, const struct device_driver *drv); +/* + * Static dax regions are regions created by an external subsystem + * nvdimm where a single range is assigned. Its boundaries are by the external + * subsystem and are usually limited to one physical memory range. For example, + * for PMEM it is usually defined by NVDIMM Namespace boundaries (i.e. a + * single contiguous range) + * + * On dynamic dax regions, the assigned region can be partitioned by dax core + * into multiple subdivisions. A subdivision is represented into one + * /dev/daxN.M device composed by one or more potentially discontiguous ranges. + * + * When allocating a dax region, drivers must set whether it's static + * (IORESOURCE_DAX_STATIC). On static dax devices, the @pgmap is pre-assigned + * to dax core when calling devm_create_dev_dax(), whereas in dynamic dax + * devices it is NULL but afterwards allocated by dax core on device ->probe(). + * Care is needed to make sure that dynamic dax devices are torn down with a + * cleared @pgmap field (see kill_dev_dax()). + */ static bool is_static(struct dax_region *dax_region) { return (dax_region->res.flags & IORESOURCE_DAX_STATIC) != 0; } +bool static_dev_dax(struct dev_dax *dev_dax) +{ + return is_static(dev_dax->region); +} +EXPORT_SYMBOL_GPL(static_dev_dax); + static u64 dev_dax_size(struct dev_dax *dev_dax) { u64 size = 0; int i; - device_lock_assert(&dev_dax->dev); + lockdep_assert_held(&dax_dev_rwsem); for (i = 0; i < dev_dax->nr_range; i++) size += range_len(&dev_dax->ranges[i].range); @@ -153,8 +203,15 @@ static int dax_bus_probe(struct device *dev) struct dev_dax *dev_dax = to_dev_dax(dev); struct dax_region *dax_region = dev_dax->region; int rc; + u64 size; - if (dev_dax_size(dev_dax) == 0 || dev_dax->id < 0) + rc = down_read_interruptible(&dax_dev_rwsem); + if (rc) + return rc; + size = dev_dax_size(dev_dax); + up_read(&dax_dev_rwsem); + + if (size == 0 || dev_dax->id < 0) return -ENXIO; rc = dax_drv->probe(dev_dax); @@ -172,18 +229,16 @@ static int dax_bus_probe(struct device *dev) return 0; } -static int dax_bus_remove(struct device *dev) +static void dax_bus_remove(struct device *dev) { struct dax_device_driver *dax_drv = to_dax_drv(dev->driver); struct dev_dax *dev_dax = to_dev_dax(dev); if (dax_drv->remove) dax_drv->remove(dev_dax); - - return 0; } -static struct bus_type dax_bus_type = { +static const struct bus_type dax_bus_type = { .name = "dax", .uevent = dax_bus_uevent, .match = dax_bus_match, @@ -192,18 +247,13 @@ static struct bus_type dax_bus_type = { .drv_groups = dax_drv_groups, }; -static int dax_bus_match(struct device *dev, struct device_driver *drv) +static int dax_bus_match(struct device *dev, const struct device_driver *drv) { - struct dax_device_driver *dax_drv = to_dax_drv(drv); + const struct dax_device_driver *dax_drv = to_dax_drv(drv); - /* - * All but the 'device-dax' driver, which has 'match_always' - * set, requires an exact id match. - */ - if (dax_drv->match_always) + if (dax_match_id(dax_drv, dev)) return 1; - - return dax_match_id(dax_drv, dev); + return dax_match_type(dax_drv, dev); } /* @@ -216,7 +266,7 @@ static ssize_t id_show(struct device *dev, { struct dax_region *dax_region = dev_get_drvdata(dev); - return sprintf(buf, "%d\n", dax_region->id); + return sysfs_emit(buf, "%d\n", dax_region->id); } static DEVICE_ATTR_RO(id); @@ -225,8 +275,8 @@ static ssize_t region_size_show(struct device *dev, { struct dax_region *dax_region = dev_get_drvdata(dev); - return sprintf(buf, "%llu\n", (unsigned long long) - resource_size(&dax_region->res)); + return sysfs_emit(buf, "%llu\n", + (unsigned long long)resource_size(&dax_region->res)); } static struct device_attribute dev_attr_region_size = __ATTR(size, 0444, region_size_show, NULL); @@ -236,7 +286,7 @@ static ssize_t region_align_show(struct device *dev, { struct dax_region *dax_region = dev_get_drvdata(dev); - return sprintf(buf, "%u\n", dax_region->align); + return sysfs_emit(buf, "%u\n", dax_region->align); } static struct device_attribute dev_attr_region_align = __ATTR(align, 0400, region_align_show, NULL); @@ -249,7 +299,7 @@ static unsigned long long dax_region_avail_size(struct dax_region *dax_region) resource_size_t size = resource_size(&dax_region->res); struct resource *res; - device_lock_assert(dax_region->dev); + lockdep_assert_held(&dax_region_rwsem); for_each_dax_region_resource(dax_region, res) size -= resource_size(res); @@ -261,12 +311,15 @@ static ssize_t available_size_show(struct device *dev, { struct dax_region *dax_region = dev_get_drvdata(dev); unsigned long long size; + int rc; - device_lock(dev); + rc = down_read_interruptible(&dax_region_rwsem); + if (rc) + return rc; size = dax_region_avail_size(dax_region); - device_unlock(dev); + up_read(&dax_region_rwsem); - return sprintf(buf, "%llu\n", size); + return sysfs_emit(buf, "%llu\n", size); } static DEVICE_ATTR_RO(available_size); @@ -280,10 +333,12 @@ static ssize_t seed_show(struct device *dev, if (is_static(dax_region)) return -EINVAL; - device_lock(dev); + rc = down_read_interruptible(&dax_region_rwsem); + if (rc) + return rc; seed = dax_region->seed; - rc = sprintf(buf, "%s\n", seed ? dev_name(seed) : ""); - device_unlock(dev); + rc = sysfs_emit(buf, "%s\n", seed ? dev_name(seed) : ""); + up_read(&dax_region_rwsem); return rc; } @@ -299,14 +354,18 @@ static ssize_t create_show(struct device *dev, if (is_static(dax_region)) return -EINVAL; - device_lock(dev); + rc = down_read_interruptible(&dax_region_rwsem); + if (rc) + return rc; youngest = dax_region->youngest; - rc = sprintf(buf, "%s\n", youngest ? dev_name(youngest) : ""); - device_unlock(dev); + rc = sysfs_emit(buf, "%s\n", youngest ? dev_name(youngest) : ""); + up_read(&dax_region_rwsem); return rc; } +static struct dev_dax *__devm_create_dev_dax(struct dev_dax_data *data); + static ssize_t create_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { @@ -324,7 +383,9 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr, if (val != 1) return -EINVAL; - device_lock(dev); + rc = down_write_killable(&dax_region_rwsem); + if (rc) + return rc; avail = dax_region_avail_size(dax_region); if (avail == 0) rc = -ENOSPC; @@ -333,8 +394,9 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr, .dax_region = dax_region, .size = 0, .id = -1, + .memmap_on_memory = false, }; - struct dev_dax *dev_dax = devm_create_dev_dax(&data); + struct dev_dax *dev_dax = __devm_create_dev_dax(&data); if (IS_ERR(dev_dax)) rc = PTR_ERR(dev_dax); @@ -352,7 +414,7 @@ static ssize_t create_store(struct device *dev, struct device_attribute *attr, rc = len; } } - device_unlock(dev); + up_write(&dax_region_rwsem); return rc; } @@ -365,6 +427,14 @@ void kill_dev_dax(struct dev_dax *dev_dax) kill_dax(dax_dev); unmap_mapping_range(inode->i_mapping, 0, 0, 1); + + /* + * Dynamic dax region have the pgmap allocated via dev_kzalloc() + * and thus freed by devm. Clear the pgmap to not have stale pgmap + * ranges on probe() from previous reconfigurations of region devices. + */ + if (!static_dev_dax(dev_dax)) + dev_dax->pgmap = NULL; } EXPORT_SYMBOL_GPL(kill_dev_dax); @@ -374,7 +444,7 @@ static void trim_dev_dax_range(struct dev_dax *dev_dax) struct range *range = &dev_dax->ranges[i].range; struct dax_region *dax_region = dev_dax->region; - device_lock_assert(dax_region->dev); + lockdep_assert_held_write(&dax_region_rwsem); dev_dbg(&dev_dax->dev, "delete range[%d]: %#llx:%#llx\n", i, (unsigned long long)range->start, (unsigned long long)range->end); @@ -398,39 +468,70 @@ static void unregister_dev_dax(void *dev) dev_dbg(dev, "%s\n", __func__); + down_write(&dax_region_rwsem); kill_dev_dax(dev_dax); - free_dev_dax_ranges(dev_dax); device_del(dev); + free_dev_dax_ranges(dev_dax); put_device(dev); + up_write(&dax_region_rwsem); +} + +static void dax_region_free(struct kref *kref) +{ + struct dax_region *dax_region; + + dax_region = container_of(kref, struct dax_region, kref); + kfree(dax_region); +} + +static void dax_region_put(struct dax_region *dax_region) +{ + kref_put(&dax_region->kref, dax_region_free); } /* a return value >= 0 indicates this invocation invalidated the id */ static int __free_dev_dax_id(struct dev_dax *dev_dax) { - struct dax_region *dax_region = dev_dax->region; - struct device *dev = &dev_dax->dev; + struct dax_region *dax_region; int rc = dev_dax->id; - device_lock_assert(dev); + lockdep_assert_held_write(&dax_dev_rwsem); - if (is_static(dax_region) || dev_dax->id < 0) + if (!dev_dax->dyn_id || dev_dax->id < 0) return -1; + dax_region = dev_dax->region; ida_free(&dax_region->ida, dev_dax->id); + dax_region_put(dax_region); dev_dax->id = -1; return rc; } static int free_dev_dax_id(struct dev_dax *dev_dax) { - struct device *dev = &dev_dax->dev; int rc; - device_lock(dev); + rc = down_write_killable(&dax_dev_rwsem); + if (rc) + return rc; rc = __free_dev_dax_id(dev_dax); - device_unlock(dev); + up_write(&dax_dev_rwsem); return rc; } +static int alloc_dev_dax_id(struct dev_dax *dev_dax) +{ + struct dax_region *dax_region = dev_dax->region; + int id; + + id = ida_alloc(&dax_region->ida, GFP_KERNEL); + if (id < 0) + return id; + kref_get(&dax_region->kref); + dev_dax->dyn_id = true; + dev_dax->id = id; + return id; +} + static ssize_t delete_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { @@ -450,6 +551,7 @@ static ssize_t delete_store(struct device *dev, struct device_attribute *attr, device_lock(dev); device_lock(victim); dev_dax = to_dev_dax(victim); + down_write(&dax_dev_rwsem); if (victim->driver || dev_dax_size(dev_dax)) rc = -EBUSY; else { @@ -469,6 +571,7 @@ static ssize_t delete_store(struct device *dev, struct device_attribute *attr, } else rc = -EBUSY; } + up_write(&dax_dev_rwsem); device_unlock(victim); /* won the race to invalidate the device, clean it up */ @@ -518,20 +621,6 @@ static const struct attribute_group *dax_region_attribute_groups[] = { NULL, }; -static void dax_region_free(struct kref *kref) -{ - struct dax_region *dax_region; - - dax_region = container_of(kref, struct dax_region, kref); - kfree(dax_region); -} - -void dax_region_put(struct dax_region *dax_region) -{ - kref_put(&dax_region->kref, dax_region_free); -} -EXPORT_SYMBOL_GPL(dax_region_put); - static void dax_region_unregister(void *region) { struct dax_region *dax_region = region; @@ -583,7 +672,6 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, return NULL; } - kref_get(&dax_region->kref); if (devm_add_action_or_reset(parent, dax_region_unregister, dax_region)) return NULL; return dax_region; @@ -593,10 +681,12 @@ EXPORT_SYMBOL_GPL(alloc_dax_region); static void dax_mapping_release(struct device *dev) { struct dax_mapping *mapping = to_dax_mapping(dev); - struct dev_dax *dev_dax = to_dev_dax(dev->parent); + struct device *parent = dev->parent; + struct dev_dax *dev_dax = to_dev_dax(parent); ida_free(&dev_dax->ida, mapping->id); kfree(mapping); + put_device(parent); } static void unregister_dax_mapping(void *data) @@ -604,41 +694,35 @@ static void unregister_dax_mapping(void *data) struct device *dev = data; struct dax_mapping *mapping = to_dax_mapping(dev); struct dev_dax *dev_dax = to_dev_dax(dev->parent); - struct dax_region *dax_region = dev_dax->region; dev_dbg(dev, "%s\n", __func__); - device_lock_assert(dax_region->dev); - dev_dax->ranges[mapping->range_id].mapping = NULL; mapping->range_id = -1; - device_del(dev); - put_device(dev); + device_unregister(dev); } static struct dev_dax_range *get_dax_range(struct device *dev) { struct dax_mapping *mapping = to_dax_mapping(dev); struct dev_dax *dev_dax = to_dev_dax(dev->parent); - struct dax_region *dax_region = dev_dax->region; + int rc; - device_lock(dax_region->dev); + rc = down_write_killable(&dax_region_rwsem); + if (rc) + return NULL; if (mapping->range_id < 0) { - device_unlock(dax_region->dev); + up_write(&dax_region_rwsem); return NULL; } return &dev_dax->ranges[mapping->range_id]; } -static void put_dax_range(struct dev_dax_range *dax_range) +static void put_dax_range(void) { - struct dax_mapping *mapping = dax_range->mapping; - struct dev_dax *dev_dax = to_dev_dax(mapping->dev.parent); - struct dax_region *dax_region = dev_dax->region; - - device_unlock(dax_region->dev); + up_write(&dax_region_rwsem); } static ssize_t start_show(struct device *dev, @@ -650,8 +734,8 @@ static ssize_t start_show(struct device *dev, dax_range = get_dax_range(dev); if (!dax_range) return -ENXIO; - rc = sprintf(buf, "%#llx\n", dax_range->range.start); - put_dax_range(dax_range); + rc = sysfs_emit(buf, "%#llx\n", dax_range->range.start); + put_dax_range(); return rc; } @@ -666,8 +750,8 @@ static ssize_t end_show(struct device *dev, dax_range = get_dax_range(dev); if (!dax_range) return -ENXIO; - rc = sprintf(buf, "%#llx\n", dax_range->range.end); - put_dax_range(dax_range); + rc = sysfs_emit(buf, "%#llx\n", dax_range->range.end); + put_dax_range(); return rc; } @@ -682,8 +766,8 @@ static ssize_t pgoff_show(struct device *dev, dax_range = get_dax_range(dev); if (!dax_range) return -ENXIO; - rc = sprintf(buf, "%#lx\n", dax_range->pgoff); - put_dax_range(dax_range); + rc = sysfs_emit(buf, "%#lx\n", dax_range->pgoff); + put_dax_range(); return rc; } @@ -705,7 +789,7 @@ static const struct attribute_group *dax_mapping_attribute_groups[] = { NULL, }; -static struct device_type dax_mapping_type = { +static const struct device_type dax_mapping_type = { .release = dax_mapping_release, .groups = dax_mapping_attribute_groups, }; @@ -717,7 +801,7 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id) struct device *dev; int rc; - device_lock_assert(dax_region->dev); + lockdep_assert_held_write(&dax_region_rwsem); if (dev_WARN_ONCE(&dev_dax->dev, !dax_region->dev->driver, "region disabled\n")) @@ -736,6 +820,7 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id) dev = &mapping->dev; device_initialize(dev); dev->parent = &dev_dax->dev; + get_device(dev->parent); dev->type = &dax_mapping_type; dev_set_name(dev, "mapping%d", mapping->id); rc = device_add(dev); @@ -762,7 +847,7 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start, struct resource *alloc; int i, rc; - device_lock_assert(dax_region->dev); + lockdep_assert_held_write(&dax_region_rwsem); /* handle the seed alloc special case */ if (!size) { @@ -816,13 +901,12 @@ static int adjust_dev_dax_range(struct dev_dax *dev_dax, struct resource *res, r { int last_range = dev_dax->nr_range - 1; struct dev_dax_range *dax_range = &dev_dax->ranges[last_range]; - struct dax_region *dax_region = dev_dax->region; bool is_shrink = resource_size(res) > size; struct range *range = &dax_range->range; struct device *dev = &dev_dax->dev; int rc; - device_lock_assert(dax_region->dev); + lockdep_assert_held_write(&dax_region_rwsem); if (dev_WARN_ONCE(dev, !size, "deletion is handled by dev_dax_shrink\n")) return -EINVAL; @@ -848,12 +932,15 @@ static ssize_t size_show(struct device *dev, { struct dev_dax *dev_dax = to_dev_dax(dev); unsigned long long size; + int rc; - device_lock(dev); + rc = down_read_interruptible(&dax_dev_rwsem); + if (rc) + return rc; size = dev_dax_size(dev_dax); - device_unlock(dev); + up_read(&dax_dev_rwsem); - return sprintf(buf, "%llu\n", size); + return sysfs_emit(buf, "%llu\n", size); } static bool alloc_is_aligned(struct dev_dax *dev_dax, resource_size_t size) @@ -1021,17 +1108,27 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr, return -EINVAL; } - device_lock(dax_region->dev); + rc = down_write_killable(&dax_region_rwsem); + if (rc) + return rc; if (!dax_region->dev->driver) { - device_unlock(dax_region->dev); - return -ENXIO; + rc = -ENXIO; + goto err_region; } - device_lock(dev); + rc = down_write_killable(&dax_dev_rwsem); + if (rc) + goto err_dev; + rc = dev_dax_resize(dax_region, dev_dax, val); - device_unlock(dev); - device_unlock(dax_region->dev); - return rc == 0 ? len : rc; +err_dev: + up_write(&dax_dev_rwsem); +err_region: + up_write(&dax_region_rwsem); + + if (rc == 0) + return len; + return rc; } static DEVICE_ATTR_RW(size); @@ -1078,19 +1175,24 @@ static ssize_t mapping_store(struct device *dev, struct device_attribute *attr, if (rc) return rc; - rc = -ENXIO; - device_lock(dax_region->dev); + rc = down_write_killable(&dax_region_rwsem); + if (rc) + return rc; if (!dax_region->dev->driver) { - device_unlock(dax_region->dev); + up_write(&dax_region_rwsem); + return rc; + } + rc = down_write_killable(&dax_dev_rwsem); + if (rc) { + up_write(&dax_region_rwsem); return rc; } - device_lock(dev); to_alloc = range_len(&r); if (alloc_is_aligned(dev_dax, to_alloc)) rc = alloc_dev_dax_range(dev_dax, r.start, to_alloc); - device_unlock(dev); - device_unlock(dax_region->dev); + up_write(&dax_dev_rwsem); + up_write(&dax_region_rwsem); return rc == 0 ? len : rc; } @@ -1101,7 +1203,7 @@ static ssize_t align_show(struct device *dev, { struct dev_dax *dev_dax = to_dev_dax(dev); - return sprintf(buf, "%d\n", dev_dax->align); + return sysfs_emit(buf, "%d\n", dev_dax->align); } static ssize_t dev_dax_validate_align(struct dev_dax *dev_dax) @@ -1137,13 +1239,19 @@ static ssize_t align_store(struct device *dev, struct device_attribute *attr, if (!dax_align_valid(val)) return -EINVAL; - device_lock(dax_region->dev); + rc = down_write_killable(&dax_region_rwsem); + if (rc) + return rc; if (!dax_region->dev->driver) { - device_unlock(dax_region->dev); + up_write(&dax_region_rwsem); return -ENXIO; } - device_lock(dev); + rc = down_write_killable(&dax_dev_rwsem); + if (rc) { + up_write(&dax_region_rwsem); + return rc; + } if (dev->driver) { rc = -EBUSY; goto out_unlock; @@ -1155,8 +1263,8 @@ static ssize_t align_store(struct device *dev, struct device_attribute *attr, if (rc) dev_dax->align = align_save; out_unlock: - device_unlock(dev); - device_unlock(dax_region->dev); + up_write(&dax_dev_rwsem); + up_write(&dax_region_rwsem); return rc == 0 ? len : rc; } static DEVICE_ATTR_RW(align); @@ -1173,7 +1281,7 @@ static ssize_t target_node_show(struct device *dev, { struct dev_dax *dev_dax = to_dev_dax(dev); - return sprintf(buf, "%d\n", dev_dax_target_node(dev_dax)); + return sysfs_emit(buf, "%d\n", dev_dax_target_node(dev_dax)); } static DEVICE_ATTR_RO(target_node); @@ -1189,7 +1297,7 @@ static ssize_t resource_show(struct device *dev, else start = dev_dax->ranges[0].range.start; - return sprintf(buf, "%#llx\n", start); + return sysfs_emit(buf, "%#llx\n", start); } static DEVICE_ATTR(resource, 0400, resource_show, NULL); @@ -1200,17 +1308,59 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, * We only ever expect to handle device-dax instances, i.e. the * @type argument to MODULE_ALIAS_DAX_DEVICE() is always zero */ - return sprintf(buf, DAX_DEVICE_MODALIAS_FMT "\n", 0); + return sysfs_emit(buf, DAX_DEVICE_MODALIAS_FMT "\n", 0); } static DEVICE_ATTR_RO(modalias); static ssize_t numa_node_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", dev_to_node(dev)); + return sysfs_emit(buf, "%d\n", dev_to_node(dev)); } static DEVICE_ATTR_RO(numa_node); +static ssize_t memmap_on_memory_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + + return sysfs_emit(buf, "%d\n", dev_dax->memmap_on_memory); +} + +static ssize_t memmap_on_memory_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + bool val; + int rc; + + rc = kstrtobool(buf, &val); + if (rc) + return rc; + + if (val == true && !mhp_supports_memmap_on_memory()) { + dev_dbg(dev, "memmap_on_memory is not available\n"); + return -EOPNOTSUPP; + } + + rc = down_write_killable(&dax_dev_rwsem); + if (rc) + return rc; + + if (dev_dax->memmap_on_memory != val && dev->driver && + to_dax_drv(dev->driver)->type == DAXDRV_KMEM_TYPE) { + up_write(&dax_dev_rwsem); + return -EBUSY; + } + + dev_dax->memmap_on_memory = val; + up_write(&dax_dev_rwsem); + + return len; +} +static DEVICE_ATTR_RW(memmap_on_memory); + static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) { struct device *dev = container_of(kobj, struct device, kobj); @@ -1237,6 +1387,7 @@ static struct attribute *dev_dax_attributes[] = { &dev_attr_align.attr, &dev_attr_resource.attr, &dev_attr_numa_node.attr, + &dev_attr_memmap_on_memory.attr, NULL, }; @@ -1253,12 +1404,10 @@ static const struct attribute_group *dax_attribute_groups[] = { static void dev_dax_release(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); - struct dax_region *dax_region = dev_dax->region; struct dax_device *dax_dev = dev_dax->dax_dev; put_dax(dax_dev); free_dev_dax_id(dev_dax); - dax_region_put(dax_region); kfree(dev_dax->pgmap); kfree(dev_dax); } @@ -1268,7 +1417,7 @@ static const struct device_type dev_dax_type = { .groups = dax_attribute_groups, }; -struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) +static struct dev_dax *__devm_create_dev_dax(struct dev_dax_data *data) { struct dax_region *dax_region = data->dax_region; struct device *parent = dax_region->dev; @@ -1282,6 +1431,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) if (!dev_dax) return ERR_PTR(-ENOMEM); + dev_dax->region = dax_region; if (is_static(dax_region)) { if (dev_WARN_ONCE(parent, data->id < 0, "dynamic id specified to static region\n")) { @@ -1297,13 +1447,11 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) goto err_id; } - rc = ida_alloc(&dax_region->ida, GFP_KERNEL); + rc = alloc_dev_dax_id(dev_dax); if (rc < 0) goto err_id; - dev_dax->id = rc; } - dev_dax->region = dax_region; dev = &dev_dax->dev; device_initialize(dev); dev_set_name(dev, "dax%d.%d", dax_region->id, dev_dax->id); @@ -1325,14 +1473,17 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) } /* - * No 'host' or dax_operations since there is no access to this - * device outside of mmap of the resulting character device. + * No dax_operations since there is no access to this device outside of + * mmap of the resulting character device. */ - dax_dev = alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC); + dax_dev = alloc_dax(dev_dax, NULL); if (IS_ERR(dax_dev)) { rc = PTR_ERR(dax_dev); goto err_alloc_dax; } + set_dax_synchronous(dax_dev); + set_dax_nocache(dax_dev); + set_dax_nomc(dax_dev); /* a device_dax instance is dead while the driver is not attached */ kill_dax(dax_dev); @@ -1341,14 +1492,12 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) dev_dax->target_node = dax_region->target_node; dev_dax->align = dax_region->align; ida_init(&dev_dax->ida); - kref_get(&dax_region->kref); + + dev_dax->memmap_on_memory = data->memmap_on_memory; inode = dax_inode(dax_dev); dev->devt = inode->i_rdev; - if (data->subsys == DEV_DAX_BUS) - dev->bus = &dax_bus_type; - else - dev->class = dax_class; + dev->bus = &dax_bus_type; dev->parent = parent; dev->type = &dev_dax_type; @@ -1383,15 +1532,23 @@ err_id: return ERR_PTR(rc); } -EXPORT_SYMBOL_GPL(devm_create_dev_dax); -static int match_always_count; +struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) +{ + struct dev_dax *dev_dax; + + down_write(&dax_region_rwsem); + dev_dax = __devm_create_dev_dax(data); + up_write(&dax_region_rwsem); + + return dev_dax; +} +EXPORT_SYMBOL_GPL(devm_create_dev_dax); int __dax_driver_register(struct dax_device_driver *dax_drv, struct module *module, const char *mod_name) { struct device_driver *drv = &dax_drv->drv; - int rc = 0; /* * dax_bus_probe() calls dax_drv->probe() unconditionally. @@ -1406,26 +1563,7 @@ int __dax_driver_register(struct dax_device_driver *dax_drv, drv->mod_name = mod_name; drv->bus = &dax_bus_type; - /* there can only be one default driver */ - mutex_lock(&dax_bus_lock); - match_always_count += dax_drv->match_always; - if (match_always_count > 1) { - match_always_count--; - WARN_ON(1); - rc = -EINVAL; - } - mutex_unlock(&dax_bus_lock); - if (rc) - return rc; - - rc = driver_register(drv); - if (rc && dax_drv->match_always) { - mutex_lock(&dax_bus_lock); - match_always_count -= dax_drv->match_always; - mutex_unlock(&dax_bus_lock); - } - - return rc; + return driver_register(drv); } EXPORT_SYMBOL_GPL(__dax_driver_register); @@ -1435,7 +1573,6 @@ void dax_driver_unregister(struct dax_device_driver *dax_drv) struct dax_id *dax_id, *_id; mutex_lock(&dax_bus_lock); - match_always_count -= dax_drv->match_always; list_for_each_entry_safe(dax_id, _id, &dax_drv->ids, list) { list_del(&dax_id->list); kfree(dax_id); @@ -1447,22 +1584,10 @@ EXPORT_SYMBOL_GPL(dax_driver_unregister); int __init dax_bus_init(void) { - int rc; - - if (IS_ENABLED(CONFIG_DEV_DAX_PMEM_COMPAT)) { - dax_class = class_create(THIS_MODULE, "dax"); - if (IS_ERR(dax_class)) - return PTR_ERR(dax_class); - } - - rc = bus_register(&dax_bus_type); - if (rc) - class_destroy(dax_class); - return rc; + return bus_register(&dax_bus_type); } void __exit dax_bus_exit(void) { bus_unregister(&dax_bus_type); - class_destroy(dax_class); } |