lightnvm: control life of nvm_dev in driver

LightNVM compatible device drivers does not have a method to expose
LightNVM specific sysfs entries.

To enable LightNVM sysfs entries to be exposed, lightnvm device
drivers require a struct device to attach it to. To allow both the
actual device driver and lightnvm sysfs entries to coexist, the device
driver tracks the lifetime of the nvm_dev structure.

This patch refactors NVMe and null_blk to handle the lifetime of struct
nvm_dev, which eliminates the need for struct gendisk when a lightnvm
compatible device is provided.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Matias Bjørling 2016-09-16 14:25:07 +02:00 committed by Jens Axboe
parent b21d5b3017
commit b0b4e09c1a
6 changed files with 83 additions and 68 deletions

View File

@ -34,6 +34,7 @@ struct nullb {
unsigned int index;
struct request_queue *q;
struct gendisk *disk;
struct nvm_dev *ndev;
struct blk_mq_tag_set tag_set;
struct hrtimer timer;
unsigned int queue_depth;
@ -550,12 +551,29 @@ static struct nvm_dev_ops null_lnvm_dev_ops = {
static int null_nvm_register(struct nullb *nullb)
{
return nvm_register(nullb->q, nullb->disk_name, &null_lnvm_dev_ops);
struct nvm_dev *dev;
int rv;
dev = nvm_alloc_dev(0);
if (!dev)
return -ENOMEM;
dev->q = nullb->q;
memcpy(dev->name, nullb->disk_name, DISK_NAME_LEN);
dev->ops = &null_lnvm_dev_ops;
rv = nvm_register(dev);
if (rv) {
kfree(dev);
return rv;
}
nullb->ndev = dev;
return 0;
}
static void null_nvm_unregister(struct nullb *nullb)
{
nvm_unregister(nullb->disk_name);
nvm_unregister(nullb->ndev);
}
#else
static int null_nvm_register(struct nullb *nullb)

View File

@ -660,23 +660,16 @@ static void nvm_exit(struct nvm_dev *dev)
pr_info("nvm: successfully unloaded\n");
}
int nvm_register(struct request_queue *q, char *disk_name,
struct nvm_dev_ops *ops)
struct nvm_dev *nvm_alloc_dev(int node)
{
return kzalloc_node(sizeof(struct nvm_dev), GFP_KERNEL, node);
}
EXPORT_SYMBOL(nvm_alloc_dev);
int nvm_register(struct nvm_dev *dev)
{
struct nvm_dev *dev;
int ret;
if (!ops->identity)
return -EINVAL;
dev = kzalloc(sizeof(struct nvm_dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->q = q;
dev->ops = ops;
strncpy(dev->name, disk_name, DISK_NAME_LEN);
ret = nvm_init(dev);
if (ret)
goto err_init;
@ -714,29 +707,17 @@ int nvm_register(struct request_queue *q, char *disk_name,
return 0;
err_init:
kfree(dev->lun_map);
kfree(dev);
return ret;
}
EXPORT_SYMBOL(nvm_register);
void nvm_unregister(char *disk_name)
void nvm_unregister(struct nvm_dev *dev)
{
struct nvm_dev *dev;
down_write(&nvm_lock);
dev = nvm_find_nvm_dev(disk_name);
if (!dev) {
pr_err("nvm: could not find device %s to unregister\n",
disk_name);
up_write(&nvm_lock);
return;
}
list_del(&dev->devices);
up_write(&nvm_lock);
nvm_exit(dev);
kfree(dev);
}
EXPORT_SYMBOL(nvm_unregister);

View File

@ -156,12 +156,14 @@ static void nvme_free_ns(struct kref *kref)
{
struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
if (ns->type == NVME_NS_LIGHTNVM)
nvme_nvm_unregister(ns->queue, ns->disk->disk_name);
if (ns->ndev)
nvme_nvm_unregister(ns);
spin_lock(&dev_list_lock);
ns->disk->private_data = NULL;
spin_unlock(&dev_list_lock);
if (ns->disk) {
spin_lock(&dev_list_lock);
ns->disk->private_data = NULL;
spin_unlock(&dev_list_lock);
}
put_disk(ns->disk);
ida_simple_remove(&ns->ctrl->ns_ida, ns->instance);
@ -891,8 +893,7 @@ static void nvme_config_discard(struct nvme_ns *ns)
static int nvme_revalidate_ns(struct nvme_ns *ns, struct nvme_id_ns **id)
{
if (nvme_identify_ns(ns->ctrl, ns->ns_id, id)) {
dev_warn(disk_to_dev(ns->disk), "%s: Identify failure\n",
__func__);
dev_warn(ns->ctrl->dev, "%s: Identify failure\n", __func__);
return -ENODEV;
}
@ -1683,18 +1684,11 @@ static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
goto out_free_queue;
if (nvme_nvm_ns_supported(ns, id)) {
if (nvme_nvm_register(ns->queue, disk_name)) {
dev_warn(ctrl->dev,
"%s: LightNVM init failure\n", __func__);
if (nvme_nvm_register(ns, disk_name, node)) {
dev_warn(ctrl->dev, "%s: LightNVM init failure\n",
__func__);
goto out_free_id;
}
disk = alloc_disk_node(0, node);
if (!disk)
goto out_free_id;
memcpy(disk->disk_name, disk_name, DISK_NAME_LEN);
ns->disk = disk;
ns->type = NVME_NS_LIGHTNVM;
} else {
disk = alloc_disk_node(0, node);
if (!disk)
@ -1718,7 +1712,7 @@ static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
kfree(id);
if (ns->type == NVME_NS_LIGHTNVM)
if (ns->ndev)
return;
device_add_disk(ctrl->device, ns->disk);
@ -1742,7 +1736,7 @@ static void nvme_ns_remove(struct nvme_ns *ns)
if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
return;
if (ns->disk->flags & GENHD_FL_UP) {
if (ns->disk && ns->disk->flags & GENHD_FL_UP) {
if (blk_get_integrity(ns->disk))
blk_integrity_unregister(ns->disk);
sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
@ -1765,7 +1759,7 @@ static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
ns = nvme_find_get_ns(ctrl, nsid);
if (ns) {
if (revalidate_disk(ns->disk))
if (ns->disk && revalidate_disk(ns->disk))
nvme_ns_remove(ns);
nvme_put_ns(ns);
} else
@ -2070,7 +2064,7 @@ void nvme_kill_queues(struct nvme_ctrl *ctrl)
* Revalidating a dead namespace sets capacity to 0. This will
* end buffered writers dirtying pages that can't be synced.
*/
if (!test_and_set_bit(NVME_NS_DEAD, &ns->flags))
if (ns->disk && !test_and_set_bit(NVME_NS_DEAD, &ns->flags))
revalidate_disk(ns->disk);
blk_set_queue_dying(ns->queue);

View File

@ -474,9 +474,8 @@ static inline void nvme_nvm_rqtocmd(struct request *rq, struct nvm_rq *rqd,
c->ph_rw.length = cpu_to_le16(rqd->nr_ppas - 1);
if (rqd->opcode == NVM_OP_HBWRITE || rqd->opcode == NVM_OP_HBREAD)
/* momentarily hardcode the shift configuration. lba_shift from
* nvm_dev will be available in a follow-up patch */
c->hb_rw.slba = cpu_to_le64(rqd->bio->bi_iter.bi_sector >> 3);
c->hb_rw.slba = cpu_to_le64(nvme_block_nr(ns,
rqd->bio->bi_iter.bi_sector));
}
static void nvme_nvm_end_io(struct request *rq, int error)
@ -593,14 +592,32 @@ static struct nvm_dev_ops nvme_nvm_dev_ops = {
.max_phys_sect = 64,
};
int nvme_nvm_register(struct request_queue *q, char *disk_name)
int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node)
{
return nvm_register(q, disk_name, &nvme_nvm_dev_ops);
struct request_queue *q = ns->queue;
struct nvm_dev *dev;
int ret;
dev = nvm_alloc_dev(node);
if (!dev)
return -ENOMEM;
dev->q = q;
memcpy(dev->name, disk_name, DISK_NAME_LEN);
dev->ops = &nvme_nvm_dev_ops;
ns->ndev = dev;
ret = nvm_register(dev);
ns->lba_shift = ilog2(dev->sec_size) - 9;
return ret;
}
void nvme_nvm_unregister(struct request_queue *q, char *disk_name)
void nvme_nvm_unregister(struct nvme_ns *ns)
{
nvm_unregister(disk_name);
nvm_unregister(ns->ndev);
kfree(ns->ndev);
}
/* move to shared place when used in multiple places. */

View File

@ -18,6 +18,7 @@
#include <linux/pci.h>
#include <linux/kref.h>
#include <linux/blk-mq.h>
#include <linux/lightnvm.h>
enum {
/*
@ -154,6 +155,7 @@ struct nvme_ns {
struct nvme_ctrl *ctrl;
struct request_queue *queue;
struct gendisk *disk;
struct nvm_dev *ndev;
struct kref kref;
int instance;
@ -165,7 +167,6 @@ struct nvme_ns {
u16 ms;
bool ext;
u8 pi_type;
int type;
unsigned long flags;
#define NVME_NS_REMOVING 0
@ -307,15 +308,16 @@ int nvme_sg_get_version_num(int __user *ip);
#ifdef CONFIG_NVM
int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
int nvme_nvm_register(struct request_queue *q, char *disk_name);
void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node);
void nvme_nvm_unregister(struct nvme_ns *ns);
#else
static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
static inline int nvme_nvm_register(struct nvme_ns *ns, char *disk_name,
int node)
{
return 0;
}
static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
static inline void nvme_nvm_unregister(struct nvme_ns *ns) {};
static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
{

View File

@ -524,9 +524,9 @@ extern struct nvm_block *nvm_get_blk(struct nvm_dev *, struct nvm_lun *,
unsigned long);
extern void nvm_put_blk(struct nvm_dev *, struct nvm_block *);
extern int nvm_register(struct request_queue *, char *,
struct nvm_dev_ops *);
extern void nvm_unregister(char *);
extern struct nvm_dev *nvm_alloc_dev(int);
extern int nvm_register(struct nvm_dev *);
extern void nvm_unregister(struct nvm_dev *);
void nvm_mark_blk(struct nvm_dev *dev, struct ppa_addr ppa, int type);
@ -575,11 +575,14 @@ extern int nvm_dev_factory(struct nvm_dev *, int flags);
#else /* CONFIG_NVM */
struct nvm_dev_ops;
static inline int nvm_register(struct request_queue *q, char *disk_name,
struct nvm_dev_ops *ops)
static inline struct nvm_dev *nvm_alloc_dev(int node)
{
return ERR_PTR(-EINVAL);
}
static inline int nvm_register(struct nvm_dev *dev)
{
return -EINVAL;
}
static inline void nvm_unregister(char *disk_name) {}
static inline void nvm_unregister(struct nvm_dev *dev) {}
#endif /* CONFIG_NVM */
#endif /* LIGHTNVM.H */