On 11/25/2015 01:42 PM, Wenwei Tao wrote:
block creations of new targets, remove exiting targets when
underlying device was gone.
Signed-off-by: Wenwei Tao <ww.tao0320@xxxxxxxxx>
---
drivers/lightnvm/core.c | 127 ++++++++++++++++++++++++++++++-----------------
include/linux/lightnvm.h | 3 ++
2 files changed, 85 insertions(+), 45 deletions(-)
diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 39aec3a..0b71dd2 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -33,6 +33,17 @@ static LIST_HEAD(nvm_targets);
static LIST_HEAD(nvm_mgrs);
static LIST_HEAD(nvm_devices);
static DECLARE_RWSEM(nvm_lock);
+#define NVM_EXITING 1
+
+static inline int NvmExiting(struct nvm_dev *dev)
+{
+ return ((unsigned long)dev->ppalist_pool & NVM_EXITING) != 0;
+}
+
+static inline void *ppalist_pool(struct nvm_dev *dev)
+{
+ return (void *)((unsigned long)dev->ppalist_pool & ~NVM_EXITING);
+}
I think I rather want to have a state variable (so we have a state
machine for three state. Initializing, running, and stopping.
What was the reason you'll like to put it in the ppalist_pool?
ps. could you rebase it on top of the latest master. Then I'll review
the rest of it.
static struct nvm_tgt_type *nvm_find_target_type(const char *name)
{
@@ -74,7 +85,7 @@ EXPORT_SYMBOL(nvm_unregister_target);
void *nvm_dev_dma_alloc(struct nvm_dev *dev, gfp_t mem_flags,
dma_addr_t *dma_handler)
{
- return dev->ops->dev_dma_alloc(dev->q, dev->ppalist_pool, mem_flags,
+ return dev->ops->dev_dma_alloc(dev->q, ppalist_pool(dev), mem_flags,
dma_handler);
}
EXPORT_SYMBOL(nvm_dev_dma_alloc);
@@ -82,7 +93,7 @@ EXPORT_SYMBOL(nvm_dev_dma_alloc);
void nvm_dev_dma_free(struct nvm_dev *dev, void *ppa_list,
dma_addr_t dma_handler)
{
- dev->ops->dev_dma_free(dev->ppalist_pool, ppa_list, dma_handler);
+ dev->ops->dev_dma_free(ppalist_pool(dev), ppa_list, dma_handler);
}
EXPORT_SYMBOL(nvm_dev_dma_free);
@@ -206,17 +217,6 @@ static int nvm_core_init(struct nvm_dev *dev)
return 0;
}
-static void nvm_free(struct nvm_dev *dev)
-{
- if (!dev)
- return;
-
- if (dev->mt)
- dev->mt->unregister_mgr(dev);
-
- nvm_core_free(dev);
-}
-
static int nvm_init(struct nvm_dev *dev)
{
struct nvmm_type *mt;
@@ -262,6 +262,7 @@ static int nvm_init(struct nvm_dev *dev)
}
}
+ kref_init(&dev->kref);
if (!ret) {
pr_info("nvm: no compatible manager found.\n");
return 0;
@@ -278,11 +279,47 @@ err:
return ret;
}
-static void nvm_exit(struct nvm_dev *dev)
+static void nvm_remove_target(struct nvm_target *t)
{
- if (dev->ppalist_pool)
- dev->ops->destroy_dma_pool(dev->ppalist_pool);
- nvm_free(dev);
+ struct nvm_tgt_type *tt = t->type;
+ struct gendisk *tdisk = t->disk;
+ struct request_queue *q = tdisk->queue;
+
+ lockdep_assert_held(&nvm_lock);
+
+ del_gendisk(tdisk);
+ if (tt->exit)
+ tt->exit(tdisk->private_data);
+
+ blk_cleanup_queue(q);
+
+ put_disk(tdisk);
+
+ list_del(&t->list);
+ kfree(t);
+}
+
+static inline void nvm_remove_targets(struct nvm_dev *dev)
+{
+ struct nvm_target *t, *n;
+
+ list_for_each_entry_safe(t, n, &dev->online_targets, list)
+ nvm_remove_target(t);
+}
+
+static void nvm_exit(struct kref *kref)
+{
+ struct nvm_dev *dev;
+
+ dev = container_of(kref, struct nvm_dev, kref);
+ if (ppalist_pool(dev))
+ dev->ops->destroy_dma_pool(ppalist_pool(dev));
+
+ if (dev->mt)
+ dev->mt->unregister_mgr(dev);
+
+ if (dev->ops->dev_remove)
+ dev->ops->dev_remove(dev->q);
pr_info("nvm: successfully unloaded\n");
}
@@ -344,8 +381,10 @@ void nvm_unregister(char *disk_name)
}
list_del(&dev->devices);
+ nvm_remove_targets(dev);
+ dev->ppalist_pool += NVM_EXITING;
up_write(&nvm_lock);
- nvm_exit(dev);
+ kref_put(&dev->kref, nvm_exit);
}
EXPORT_SYMBOL(nvm_unregister);
@@ -366,6 +405,10 @@ static int nvm_create_target(struct nvm_dev *dev,
int ret = 0;
down_write(&nvm_lock);
+ if (NvmExiting(dev)) {
+ up_write(&nvm_lock);
+ return -ENODEV;
+ }
if (!dev->mt) {
/* register with device with a supported NVM manager */
list_for_each_entry(mt, &nvm_mgrs, list) {
@@ -439,10 +482,16 @@ static int nvm_create_target(struct nvm_dev *dev,
t->disk = tdisk;
down_write(&nvm_lock);
+ if (NvmExiting(dev)) {
+ up_write(&nvm_lock);
+ goto err_nvm_exiting;
+ }
list_add_tail(&t->list, &dev->online_targets);
up_write(&nvm_lock);
return 0;
+err_nvm_exiting:
+ del_gendisk(tdisk);
err_init:
put_disk(tdisk);
err_queue:
@@ -452,62 +501,50 @@ err_t:
return -ENOMEM;
}
-static void nvm_remove_target(struct nvm_target *t)
-{
- struct nvm_tgt_type *tt = t->type;
- struct gendisk *tdisk = t->disk;
- struct request_queue *q = tdisk->queue;
-
- lockdep_assert_held(&nvm_lock);
-
- del_gendisk(tdisk);
- if (tt->exit)
- tt->exit(tdisk->private_data);
-
- blk_cleanup_queue(q);
-
- put_disk(tdisk);
-
- list_del(&t->list);
- kfree(t);
-}
-
static int __nvm_configure_create(struct nvm_ioctl_create *create)
{
struct nvm_dev *dev;
struct nvm_ioctl_create_simple *s;
+ int ret = -EINVAL;
+
down_write(&nvm_lock);
dev = nvm_find_nvm_dev(create->dev);
- up_write(&nvm_lock);
if (!dev) {
pr_err("nvm: device not found\n");
- return -EINVAL;
+ up_write(&nvm_lock);
+ goto out;
}
+ kref_get(&dev->kref);
+ up_write(&nvm_lock);
if (create->conf.type != NVM_CONFIG_TYPE_SIMPLE) {
pr_err("nvm: config type not valid\n");
- return -EINVAL;
+ goto out;
}
s = &create->conf.s;
if (s->lun_begin > s->lun_end || s->lun_end > dev->nr_luns) {
pr_err("nvm: lun out of bound (%u:%u > %u)\n",
s->lun_begin, s->lun_end, dev->nr_luns);
- return -EINVAL;
+ goto out;
}
- return nvm_create_target(dev, create);
+ ret = nvm_create_target(dev, create);
+out:
+ if (dev)
+ kref_put(&dev->kref, nvm_exit);
+ return ret;
}
static int __nvm_configure_remove(struct nvm_ioctl_remove *remove)
{
- struct nvm_target *t = NULL;
+ struct nvm_target *n, *t = NULL;
struct nvm_dev *dev;
int ret = -1;
down_write(&nvm_lock);
list_for_each_entry(dev, &nvm_devices, devices)
- list_for_each_entry(t, &dev->online_targets, list) {
+ list_for_each_entry_safe(t, n, &dev->online_targets, list) {
if (!strcmp(remove->tgtname, t->disk->disk_name)) {
nvm_remove_target(t);
ret = 0;
diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index 69c9057..1b42305 100644
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -205,6 +205,7 @@ typedef void (nvm_destroy_dma_pool_fn)(void *);
typedef void *(nvm_dev_dma_alloc_fn)(struct request_queue *, void *, gfp_t,
dma_addr_t *);
typedef void (nvm_dev_dma_free_fn)(void *, void*, dma_addr_t);
+typedef void (nvm_dev_remove_fn) (struct request_queue *);
struct nvm_dev_ops {
nvm_id_fn *identity;
@@ -219,6 +220,7 @@ struct nvm_dev_ops {
nvm_destroy_dma_pool_fn *destroy_dma_pool;
nvm_dev_dma_alloc_fn *dev_dma_alloc;
nvm_dev_dma_free_fn *dev_dma_free;
+ nvm_dev_remove_fn *dev_remove;
uint8_t max_phys_sect;
};
@@ -252,6 +254,7 @@ struct nvm_dev {
/* Media manager */
struct nvmm_type *mt;
+ struct kref kref;
void *mp;
/* Device information */
--
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