[PATCH 7/9] lightnvm: fix media mgr registration

From: Matias BjÃrling
Date: Sun Dec 06 2015 - 05:27:38 EST


This patch fixes two issues during media manager registration.

1. The ppa pool can be used at media manager registration. Allocate the
ppa pool before that.

2. If a media manager can't be found, this should not lead to the
device being unallocated. A media manager can be registered later, that
can manage the device. Only warn if a media manager fails
initialization.

Signed-off-by: Matias BjÃrling <m@xxxxxxxxxxx>
---
drivers/lightnvm/core.c | 78 ++++++++++++++++++++++++-------------------------
1 file changed, 39 insertions(+), 39 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 4a8d1fe..8f41b24 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -97,15 +97,47 @@ static struct nvmm_type *nvm_find_mgr_type(const char *name)
return NULL;
}

+struct nvmm_type *nvm_init_mgr(struct nvm_dev *dev)
+{
+ struct nvmm_type *mt;
+ int ret;
+
+ lockdep_assert_held(&nvm_lock);
+
+ list_for_each_entry(mt, &nvm_mgrs, list) {
+ ret = mt->register_mgr(dev);
+ if (ret < 0) {
+ pr_err("nvm: media mgr failed to init (%d) on dev %s\n",
+ ret, dev->name);
+ return NULL; /* initialization failed */
+ } else if (ret > 0)
+ return mt;
+ }
+
+ return NULL;
+}
+
int nvm_register_mgr(struct nvmm_type *mt)
{
+ struct nvm_dev *dev;
int ret = 0;

down_write(&nvm_lock);
- if (nvm_find_mgr_type(mt->name))
+ if (nvm_find_mgr_type(mt->name)) {
ret = -EEXIST;
- else
+ goto finish;
+ } else {
list_add(&mt->list, &nvm_mgrs);
+ }
+
+ /* try to register media mgr if any device have none configured */
+ list_for_each_entry(dev, &nvm_devices, devices) {
+ if (dev->mt)
+ continue;
+
+ dev->mt = nvm_init_mgr(dev);
+ }
+finish:
up_write(&nvm_lock);

return ret;
@@ -123,26 +155,6 @@ void nvm_unregister_mgr(struct nvmm_type *mt)
}
EXPORT_SYMBOL(nvm_unregister_mgr);

-/* register with device with a supported manager */
-static int register_mgr(struct nvm_dev *dev)
-{
- struct nvmm_type *mt;
- int ret = 0;
-
- list_for_each_entry(mt, &nvm_mgrs, list) {
- ret = mt->register_mgr(dev);
- if (ret > 0) {
- dev->mt = mt;
- break; /* successfully initialized */
- }
- }
-
- if (!ret)
- pr_info("nvm: no compatible nvm manager found.\n");
-
- return ret;
-}
-
static struct nvm_dev *nvm_find_nvm_dev(const char *name)
{
struct nvm_dev *dev;
@@ -271,14 +283,6 @@ static int nvm_init(struct nvm_dev *dev)
goto err;
}

- down_write(&nvm_lock);
- ret = register_mgr(dev);
- up_write(&nvm_lock);
- if (ret < 0)
- goto err;
- if (!ret)
- return 0;
-
pr_info("nvm: registered %s [%u/%u/%u/%u/%u/%u]\n",
dev->name, dev->sec_per_pg, dev->nr_planes,
dev->pgs_per_blk, dev->blks_per_lun, dev->nr_luns,
@@ -334,7 +338,9 @@ int nvm_register(struct request_queue *q, char *disk_name,
}
}

+ /* register device with a supported media manager */
down_write(&nvm_lock);
+ dev->mt = nvm_init_mgr(dev);
list_add(&dev->devices, &nvm_devices);
up_write(&nvm_lock);

@@ -379,19 +385,13 @@ static int nvm_create_target(struct nvm_dev *dev,
struct nvm_tgt_type *tt;
struct nvm_target *t;
void *targetdata;
- int ret = 0;

- down_write(&nvm_lock);
if (!dev->mt) {
- ret = register_mgr(dev);
- if (!ret)
- ret = -ENODEV;
- if (ret < 0) {
- up_write(&nvm_lock);
- return ret;
- }
+ pr_info("nvm: device has no media manager registered.\n");
+ return -ENODEV;
}

+ down_write(&nvm_lock);
tt = nvm_find_target_type(create->tgttype);
if (!tt) {
pr_err("nvm: target type %s not found\n", create->tgttype);
--
2.1.4

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