nvme: add a common helper to read Identify Controller data

[linux-2.6-block.git] / drivers / nvme / host / core.c

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index e3179b33ff8116eb641116180cd577d53d6983d5..1c9f09c80b9d03a31dc9ac6e65beb8b4213a59e4 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -776,6 +776,58 @@ int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
        return ret;
 }
 
+/*
+ * Initialize the cached copies of the Identify data and various controller
+ * register in our nvme_ctrl structure.  This should be called as soon as
+ * the admin queue is fully up and running.
+ */
+int nvme_init_identify(struct nvme_ctrl *ctrl)
+{
+       struct nvme_id_ctrl *id;
+       u64 cap;
+       int ret, page_shift;
+
+       ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
+       if (ret) {
+               dev_err(ctrl->dev, "Reading CAP failed (%d)\n", ret);
+               return ret;
+       }
+       page_shift = NVME_CAP_MPSMIN(cap) + 12;
+
+       ret = nvme_identify_ctrl(ctrl, &id);
+       if (ret) {
+               dev_err(ctrl->dev, "Identify Controller failed (%d)\n", ret);
+               return -EIO;
+       }
+
+       ctrl->oncs = le16_to_cpup(&id->oncs);
+       ctrl->abort_limit = id->acl + 1;
+       ctrl->vwc = id->vwc;
+       memcpy(ctrl->serial, id->sn, sizeof(id->sn));
+       memcpy(ctrl->model, id->mn, sizeof(id->mn));
+       memcpy(ctrl->firmware_rev, id->fr, sizeof(id->fr));
+       if (id->mdts)
+               ctrl->max_hw_sectors = 1 << (id->mdts + page_shift - 9);
+       else
+               ctrl->max_hw_sectors = UINT_MAX;
+
+       if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) && id->vs[3]) {
+               unsigned int max_hw_sectors;
+
+               ctrl->stripe_size = 1 << (id->vs[3] + page_shift);
+               max_hw_sectors = ctrl->stripe_size >> (page_shift - 9);
+               if (ctrl->max_hw_sectors) {
+                       ctrl->max_hw_sectors = min(max_hw_sectors,
+                                                       ctrl->max_hw_sectors);
+               } else {
+                       ctrl->max_hw_sectors = max_hw_sectors;
+               }
+       }
+
+       kfree(id);
+       return 0;
+}
+
 static void nvme_free_ctrl(struct kref *kref)
 {
        struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);