Provide a way to disable NVMe native multipathing on a per-subsystem basis to enable a user to use dm-mpath and nvme native multipathing on the same host for different nvme devices.
Signed-off-by: Johannes Thumshirn <[email protected]> --- drivers/nvme/host/core.c | 63 +++++++++++++++++++++++++++++++++++++++++++ drivers/nvme/host/multipath.c | 34 +++++++++++++++++++---- drivers/nvme/host/nvme.h | 8 ++++++ 3 files changed, 100 insertions(+), 5 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 99b857e5a7a9..3a1c70bd9008 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2082,6 +2082,10 @@ static struct nvme_subsystem *__nvme_find_get_subsystem(const char *subsysnqn) return NULL; } +#define SUBSYS_ATTR_RW(_name) \ + struct device_attribute subsys_attr_##_name = \ + __ATTR_RW(_name) + #define SUBSYS_ATTR_RO(_name, _mode, _show) \ struct device_attribute subsys_attr_##_name = \ __ATTR(_name, _mode, _show, NULL) @@ -2112,11 +2116,62 @@ nvme_subsys_show_str_function(model); nvme_subsys_show_str_function(serial); nvme_subsys_show_str_function(firmware_rev); + +#ifdef CONFIG_NVME_MULTIPATH +static ssize_t mpath_personality_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct nvme_subsystem *subsys = + container_of(dev, struct nvme_subsystem, dev); + ssize_t ret; + + if (subsys->native_mpath) + ret = scnprintf(buf, PAGE_SIZE, "[native] other\n"); + else + ret = scnprintf(buf, PAGE_SIZE, "native [other]\n"); + + return ret; +} + +static ssize_t mpath_personality_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct nvme_subsystem *subsys = + container_of(dev, struct nvme_subsystem, dev); + bool native_mpath = false; + int ret = 0; + + if (!strncmp(buf, "native", strlen("native"))) + native_mpath = true; + else if (!strncmp(buf, "other", strlen("other"))) + native_mpath = false; + else { + pr_warn("unknown value %s\n", buf); + ret = -EINVAL; + goto out; + } + + if (subsys->native_mpath != native_mpath) { + subsys->native_mpath = native_mpath; + ret = nvme_mpath_change_personality(subsys); + } + +out: + return ret ? ret : count; +} +static SUBSYS_ATTR_RW(mpath_personality); +#endif + static struct attribute *nvme_subsys_attrs[] = { &subsys_attr_model.attr, &subsys_attr_serial.attr, &subsys_attr_firmware_rev.attr, &subsys_attr_subsysnqn.attr, +#ifdef CONFIG_NVME_MULTIPATH + &subsys_attr_mpath_personality.attr, +#endif NULL, }; @@ -2220,6 +2275,10 @@ static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) list_add_tail(&ctrl->subsys_entry, &subsys->ctrls); mutex_unlock(&subsys->lock); +#ifdef CONFIG_NVME_MULTIPATH + subsys->native_mpath = nvme_multipath; +#endif + return 0; out_unlock: @@ -2850,6 +2909,10 @@ static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl, head->ns_id = nsid; kref_init(&head->ref); +#ifdef CONFIG_NVME_MULTIPATH + head->native_mpath = ctrl->subsys->native_mpath; +#endif + nvme_report_ns_ids(ctrl, nsid, id, &head->ids); ret = __nvme_check_ids(ctrl->subsys, head); diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index d7b664ae5923..53d2610605ca 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -14,8 +14,8 @@ #include <linux/moduleparam.h> #include "nvme.h" -static bool multipath = true; -module_param(multipath, bool, 0444); +bool nvme_multipath = true; +module_param_named(multipath, nvme_multipath, bool, 0444); MODULE_PARM_DESC(multipath, "turn on native support for multiple controllers per subsystem"); @@ -29,7 +29,7 @@ MODULE_PARM_DESC(multipath, void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns, struct nvme_ctrl *ctrl, int *flags) { - if (!multipath) { + if (!ctrl->subsys->native_mpath) { sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance); } else if (ns->head->disk) { sprintf(disk_name, "nvme%dc%dn%d", ctrl->subsys->instance, @@ -181,7 +181,7 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) * We also do this for private namespaces as the namespace sharing data could * change after a rescan. */ - if (!(ctrl->subsys->cmic & (1 << 1)) || !multipath) + if (!(ctrl->subsys->cmic & (1 << 1)) || !ctrl->subsys->native_mpath) return 0; q = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE, NULL); @@ -218,7 +218,7 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) void nvme_mpath_add_disk(struct nvme_ns_head *head) { - if (!head->disk) + if (!head->disk || !head->native_mpath) return; mutex_lock(&head->subsys->lock); @@ -246,3 +246,27 @@ void nvme_mpath_remove_disk(struct nvme_ns_head *head) blk_cleanup_queue(head->disk->queue); put_disk(head->disk); } + +int nvme_mpath_change_personality(struct nvme_subsystem *subsys) +{ + struct nvme_ctrl *ctrl; + int ret = 0; + +restart: + mutex_lock(&subsys->lock); + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) { + if (!list_empty(&ctrl->namespaces)) { + mutex_unlock(&subsys->lock); + nvme_remove_namespaces(ctrl); + goto restart; + } + } + mutex_unlock(&subsys->lock); + + mutex_lock(&subsys->lock); + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) + nvme_queue_scan(ctrl); + mutex_unlock(&subsys->lock); + + return ret; +} diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 17d2f7cf3fed..f7253c074a89 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -32,6 +32,8 @@ extern unsigned int admin_timeout; #define NVME_DEFAULT_KATO 5 #define NVME_KATO_GRACE 10 +extern bool nvme_multipath; + extern struct workqueue_struct *nvme_wq; extern struct workqueue_struct *nvme_reset_wq; extern struct workqueue_struct *nvme_delete_wq; @@ -232,6 +234,10 @@ struct nvme_subsystem { u8 cmic; u16 vendor_id; struct ida ns_ida; + +#ifdef CONFIG_NVME_MULTIPATH + bool native_mpath; +#endif }; /* @@ -257,6 +263,7 @@ struct nvme_ns_head { struct bio_list requeue_list; spinlock_t requeue_lock; struct work_struct requeue_work; + bool native_mpath; #endif struct list_head list; struct srcu_struct srcu; @@ -449,6 +456,7 @@ void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl); int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl,struct nvme_ns_head *head); void nvme_mpath_add_disk(struct nvme_ns_head *head); void nvme_mpath_remove_disk(struct nvme_ns_head *head); +int nvme_mpath_change_personality(struct nvme_subsystem *subsys); static inline void nvme_mpath_clear_current_path(struct nvme_ns *ns) { -- 2.16.3
