Re: [PATCH 2/3] lightnvm: handle targets when corresponding nvm device exit

From: Wenwei Tao
Date: Thu Nov 26 2015 - 04:56:17 EST

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The reason why I put it in the ppalist_pool is that when I wrote the
code I thought state we needed was only exiting/stopping, I didn't
want to add a variable for just a bit.

I will send you a patch base on the lasted master 4.4rc2.

2015-11-25 23:39 GMT+08:00 Matias BjÃrling <m@xxxxxxxxxxx>:
> 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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Next message: Jon Hunter: "Re: [PATCH] clk: tegra: Fix bypassing of PLLs"
Previous message: Michal Hocko: "Re: [PATCH 2/2] mm: warn about ALLOC_NO_WATERMARKS request failures"
In reply to: Matias Bjørling: "Re: [PATCH 2/3] lightnvm: handle targets when corresponding nvm device exit"
Next in thread: Wenwei Tao: "[PATCH 3/3] nvme: change the interface between nvme and lightnvm"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]