On 11/27/2015 05:09 AM, Wenwei Tao wrote:
To avoid race conditions, traverse dev, media manager,
and targeet lists and also register, unregister entries
to/from them, should be always under the nvm_lock control.
Signed-off-by: Wenwei Tao <ww.tao0320@xxxxxxxxx>
---
drivers/lightnvm/core.c | 73 +++++++++++++++++++++++++------------------------
1 file changed, 38 insertions(+), 35 deletions(-)
diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 5178645..071a3e4 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -123,6 +123,24 @@ 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;
@@ -221,7 +239,6 @@ static void nvm_free(struct nvm_dev *dev)
static int nvm_init(struct nvm_dev *dev)
{
- struct nvmm_type *mt;
int ret = -EINVAL;
if (!dev->q || !dev->ops)
@@ -251,22 +268,13 @@ static int nvm_init(struct nvm_dev *dev)
pr_err("nvm: could not initialize core structures.\n");
goto err;
}
-
- /* register with device with a supported manager */
- list_for_each_entry(mt, &nvm_mgrs, list) {
- ret = mt->register_mgr(dev);
- if (ret < 0)
- goto err; /* initialization failed */
- if (ret > 0) {
- dev->mt = mt;
- break; /* successfully initialized */
- }
- }
-
- if (!ret) {
- pr_info("nvm: no compatible manager found.\n");
+ 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,
@@ -335,18 +343,18 @@ EXPORT_SYMBOL(nvm_register);
void nvm_unregister(char *disk_name)
{
+ down_write(&nvm_lock);
struct nvm_dev *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;
}
- down_write(&nvm_lock);
list_del(&dev->devices);
up_write(&nvm_lock);
-
nvm_exit(dev);
kfree(dev);
}
@@ -361,38 +369,30 @@ static int nvm_create_target(struct nvm_dev *dev,
{
struct nvm_ioctl_create_simple *s = &create->conf.s;
struct request_queue *tqueue;
- struct nvmm_type *mt;
struct gendisk *tdisk;
struct nvm_tgt_type *tt;
struct nvm_target *t;
void *targetdata;
int ret = 0;
+ down_write(&nvm_lock);
if (!dev->mt) {
- /* register with device with a supported NVM manager */
- list_for_each_entry(mt, &nvm_mgrs, list) {
- ret = mt->register_mgr(dev);
- if (ret < 0)
- return ret; /* initialization failed */
- if (ret > 0) {
- dev->mt = mt;
- break; /* successfully initialized */
- }
- }
-
- if (!ret) {
- pr_info("nvm: no compatible nvm manager found.\n");
- return -ENODEV;
+ ret = register_mgr(dev);
+ if (!ret)
+ ret = -ENODEV;
+ if (ret < 0) {
+ up_write(&nvm_lock);
+ return ret;
}
}
tt = nvm_find_target_type(create->tgttype);
if (!tt) {
pr_err("nvm: target type %s not found\n", create->tgttype);
+ up_write(&nvm_lock);
return -EINVAL;
}
- down_write(&nvm_lock);
list_for_each_entry(t, &dev->online_targets, list) {
if (!strcmp(create->tgtname, t->disk->disk_name)) {
pr_err("nvm: target name already exists.\n");
@@ -475,8 +475,9 @@ static int __nvm_configure_create(struct nvm_ioctl_create *create)
{
struct nvm_dev *dev;
struct nvm_ioctl_create_simple *s;
-
+ 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;
@@ -535,7 +536,9 @@ static int nvm_configure_show(const char *val)
return -EINVAL;
}
+ down_write(&nvm_lock);
dev = nvm_find_nvm_dev(devname);
+ up_write(&nvm_lock);
if (!dev) {
pr_err("nvm: device not found\n");
return -EINVAL;
Thanks Wei. I applied the previous version of the patch.
You can see the patches I have queued for upstream in the for-next at
https://github.com/OpenChannelSSD/linux/commits/for-next
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