lightnvm: allow to force mm initialization

System block allows the device to initialize with its configured media
manager. The system blocks is written to disk, and read again when media
manager is determined. For this to work, the backend must store the
data. Device drivers, such as null_blk, does not have any backend
storage. This patch allows the media manager to be initialized without a
storage backend.

It also fix incorrect configuration of capabilities in null_blk, as it
does not support get/set bad block interface.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 8ba1e97d573c3b804c2ee7d14946f94b4c32fc93..ae05d31c0559c600bc940885d0085fe21671e4d2 100644 (file)
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -478,7 +478,7 @@ static int null_lnvm_id(struct nvm_dev *dev, struct nvm_id *id)
        id->ver_id = 0x1;
        id->vmnt = 0;
        id->cgrps = 1;
-       id->cap = 0x3;
+       id->cap = 0x2;
        id->dom = 0x1;
 
        id->ppaf.blk_offset = 0;

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 33224cb91c5bb98ac7e464b4202dacbac71671c9..9f6acd5d1d2e9359730ad595f92d3e902bc40d17 100644 (file)
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -572,11 +572,13 @@ int nvm_register(struct request_queue *q, char *disk_name,
                }
        }
 
-       ret = nvm_get_sysblock(dev, &dev->sb);
-       if (!ret)
-               pr_err("nvm: device not initialized.\n");
-       else if (ret < 0)
-               pr_err("nvm: err (%d) on device initialization\n", ret);
+       if (dev->identity.cap & NVM_ID_DCAP_BBLKMGMT) {
+               ret = nvm_get_sysblock(dev, &dev->sb);
+               if (!ret)
+                       pr_err("nvm: device not initialized.\n");
+               else if (ret < 0)
+                       pr_err("nvm: err (%d) on device initialization\n", ret);
+       }
 
        /* register device with a supported media manager */
        down_write(&nvm_lock);
@@ -1055,9 +1057,11 @@ static long __nvm_ioctl_dev_init(struct nvm_ioctl_dev_init *init)
        strncpy(info.mmtype, init->mmtype, NVM_MMTYPE_LEN);
        info.fs_ppa.ppa = -1;
 
-       ret = nvm_init_sysblock(dev, &info);
-       if (ret)
-               return ret;
+       if (dev->identity.cap & NVM_ID_DCAP_BBLKMGMT) {
+               ret = nvm_init_sysblock(dev, &info);
+               if (ret)
+                       return ret;
+       }
 
        memcpy(&dev->sb, &info, sizeof(struct nvm_sb_info));
 
@@ -1117,7 +1121,10 @@ static long nvm_ioctl_dev_factory(struct file *file, void __user *arg)
                dev->mt = NULL;
        }
 
-       return nvm_dev_factory(dev, fact.flags);
+       if (dev->identity.cap & NVM_ID_DCAP_BBLKMGMT)
+               return nvm_dev_factory(dev, fact.flags);
+
+       return 0;
 }
 
 static long nvm_ctl_ioctl(struct file *file, uint cmd, unsigned long arg)

diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index d6750111e48ecc4603dbc5f28eb01f2810ed6303..2190419bdf0a04e549b64946037d8d61fd025781 100644 (file)
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -135,6 +135,10 @@ enum {
        /* Memory types */
        NVM_ID_FMTYPE_SLC       = 0,
        NVM_ID_FMTYPE_MLC       = 1,
+
+       /* Device capabilities */
+       NVM_ID_DCAP_BBLKMGMT    = 0x1,
+       NVM_UD_DCAP_ECC         = 0x2,
 };
 
 struct nvm_id_lp_mlc {