NVMe: Add NVME_IOCTL_SUBMIT_IO

Allow userspace to submit synchronous I/O like the SCSI sg interface does.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c
index f44d6cd..40fb2e1 100644 (file)
--- a/drivers/block/nvme.c
+++ b/drivers/block/nvme.c
@@ -780,6 +780,47 @@ static int nvme_get_range_type(struct nvme_ns *ns, unsigned long addr)
        return nvme_submit_user_admin_command(ns->dev, addr, 4096, &c);
 }
 
+static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
+{
+       struct nvme_dev *dev = ns->dev;
+       struct nvme_queue *nvmeq;
+       struct nvme_user_io io;
+       struct nvme_command c;
+       unsigned length;
+       u32 result;
+       int nents, status;
+       struct scatterlist *sg;
+
+       if (copy_from_user(&io, uio, sizeof(io)))
+               return -EFAULT;
+       length = io.nblocks << io.block_shift;
+       nents = nvme_map_user_pages(dev, io.opcode & 1, io.addr, length, &sg);
+       if (nents < 0)
+               return nents;
+
+       memset(&c, 0, sizeof(c));
+       c.rw.opcode = io.opcode;
+       c.rw.flags = io.flags;
+       c.rw.nsid = cpu_to_le32(io.nsid);
+       c.rw.slba = cpu_to_le64(io.slba);
+       c.rw.length = cpu_to_le16(io.nblocks - 1);
+       c.rw.control = cpu_to_le16(io.control);
+       c.rw.dsmgmt = cpu_to_le16(io.dsmgmt);
+       c.rw.reftag = cpu_to_le32(io.reftag);   /* XXX: endian? */
+       c.rw.apptag = cpu_to_le16(io.apptag);
+       c.rw.appmask = cpu_to_le16(io.appmask);
+       /* XXX: metadata */
+       nvme_setup_prps(&c.common, sg, length);
+
+       nvmeq = get_nvmeq(ns);
+       status = nvme_submit_sync_cmd(nvmeq, &c, &result);
+       put_nvmeq(nvmeq);
+
+       nvme_unmap_user_pages(dev, io.opcode & 1, io.addr, length, sg, nents);
+       put_user(result, &uio->result);
+       return status;
+}
+
 static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
                                                        unsigned long arg)
 {
@@ -792,6 +833,8 @@ static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
                return nvme_identify(ns, arg, 1);
        case NVME_IOCTL_GET_RANGE_TYPE:
                return nvme_get_range_type(ns, arg);
+       case NVME_IOCTL_SUBMIT_IO:
+               return nvme_submit_io(ns, (void __user *)arg);
        default:
                return -ENOTTY;
        }

diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 1c0b5ef..0aaecb0 100644 (file)
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -340,8 +340,26 @@ struct nvme_completion {
        __le16  status;         /* did the command fail, and if so, why? */
 };
 
+struct nvme_user_io {
+       __u8    opcode;
+       __u8    flags;
+       __u16   control;
+       __u32   nsid;
+       __u64   metadata;
+       __u64   addr;
+       __u64   slba;
+       __u16   nblocks;
+       __u16   block_shift;
+       __u32   dsmgmt;
+       __u32   reftag;
+       __u16   apptag;
+       __u16   appmask;
+       __u32   result;
+};
+
 #define NVME_IOCTL_IDENTIFY_NS _IOW('N', 0x40, struct nvme_id_ns)
 #define NVME_IOCTL_IDENTIFY_CTRL _IOW('N', 0x41, struct nvme_id_ctrl)
 #define NVME_IOCTL_GET_RANGE_TYPE _IOW('N', 0x42, struct nvme_lba_range_type)
+#define NVME_IOCTL_SUBMIT_IO   _IOWR('N', 0x43, struct nvme_rw_command)
 
 #endif /* _LINUX_NVME_H */