lightnvm: introduce ioctl to initialize device

Based on the previous patch, we now introduce an ioctl to initialize the
device using nvm_init_sysblock and create the necessary system blocks.
The user may specify the media manager that they wish to instantiate on
top. Default from user-space will be "gennvm".

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

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 73b8ae1dafc4fe04f580367f84827c50d95433f9..ee08fac6f327ee78078a55ca89f834821d5e0ae9 100644 (file)
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -1019,6 +1019,54 @@ static long nvm_ioctl_dev_remove(struct file *file, void __user *arg)
        return __nvm_configure_remove(&remove);
 }
 
+static void nvm_setup_nvm_sb_info(struct nvm_sb_info *info)
+{
+       info->seqnr = 1;
+       info->erase_cnt = 0;
+       info->version = 1;
+}
+
+static long __nvm_ioctl_dev_init(struct nvm_ioctl_dev_init *init)
+{
+       struct nvm_dev *dev;
+       struct nvm_sb_info info;
+
+       down_write(&nvm_lock);
+       dev = nvm_find_nvm_dev(init->dev);
+       up_write(&nvm_lock);
+       if (!dev) {
+               pr_err("nvm: device not found\n");
+               return -EINVAL;
+       }
+
+       nvm_setup_nvm_sb_info(&info);
+
+       strncpy(info.mmtype, init->mmtype, NVM_MMTYPE_LEN);
+       info.fs_ppa.ppa = -1;
+
+       return nvm_init_sysblock(dev, &info);
+}
+
+static long nvm_ioctl_dev_init(struct file *file, void __user *arg)
+{
+       struct nvm_ioctl_dev_init init;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
+       if (copy_from_user(&init, arg, sizeof(struct nvm_ioctl_dev_init)))
+               return -EFAULT;
+
+       if (init.flags != 0) {
+               pr_err("nvm: no flags supported\n");
+               return -EINVAL;
+       }
+
+       init.dev[DISK_NAME_LEN - 1] = '\0';
+
+       return __nvm_ioctl_dev_init(&init);
+}
+
 static long nvm_ctl_ioctl(struct file *file, uint cmd, unsigned long arg)
 {
        void __user *argp = (void __user *)arg;
@@ -1032,6 +1080,8 @@ static long nvm_ctl_ioctl(struct file *file, uint cmd, unsigned long arg)
                return nvm_ioctl_dev_create(file, argp);
        case NVM_DEV_REMOVE:
                return nvm_ioctl_dev_remove(file, argp);
+       case NVM_DEV_INIT:
+               return nvm_ioctl_dev_init(file, argp);
        }
        return 0;
 }

diff --git a/include/uapi/linux/lightnvm.h b/include/uapi/linux/lightnvm.h
index 0171b85e7efc2d343895c6c045248f3875d668e3..56339e2e0a46b8f47b6b723af7d0cc4408d1a68f 100644 (file)
--- a/include/uapi/linux/lightnvm.h
+++ b/include/uapi/linux/lightnvm.h
@@ -101,6 +101,12 @@ struct nvm_ioctl_remove {
        __u32 flags;
 };
 
+struct nvm_ioctl_dev_init {
+       char dev[DISK_NAME_LEN];                /* open-channel SSD device */
+       char mmtype[NVM_MMTYPE_LEN];            /* register to media manager */
+
+       __u32 flags;
+};
 
 /* The ioctl type, 'L', 0x20 - 0x2F documented in ioctl-number.txt */
 enum {
@@ -111,6 +117,9 @@ enum {
        /* device level cmds */
        NVM_DEV_CREATE_CMD,
        NVM_DEV_REMOVE_CMD,
+
+       /* Init a device to support LightNVM media managers */
+       NVM_DEV_INIT_CMD,
 };
 
 #define NVM_IOCTL 'L' /* 0x4c */
@@ -123,6 +132,8 @@ enum {
                                                struct nvm_ioctl_create)
 #define NVM_DEV_REMOVE         _IOW(NVM_IOCTL, NVM_DEV_REMOVE_CMD, \
                                                struct nvm_ioctl_remove)
+#define NVM_DEV_INIT           _IOW(NVM_IOCTL, NVM_DEV_INIT_CMD, \
+                                               struct nvm_ioctl_dev_init)
 
 #define NVM_VERSION_MAJOR      1
 #define NVM_VERSION_MINOR      0