[PATCH 08/33] TCMU PR: add functions to handle PR generation

[Zhu Lingshan]

This patch added two functions: tcmu_pr_info_gen_encode()
and tcmu_pr_info_gen_decode() to encode/decode the generations of
Persistent Reservations

Signed-off-by: Zhu Lingshan <ls...@suse.com>
---
 drivers/target/target_core_user.c | 34 +++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/target/target_core_user.c 
b/drivers/target/target_core_user.c
index 50723ac0ed22..ef79de7622b6 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -1940,6 +1940,40 @@ tcmu_pr_info_scsi2_rsv_encode(char *buf, size_t 
buf_remain,
        return rc;
 }
 
+static int
+tcmu_pr_info_gen_decode(char *str, u32 *gen)
+{
+       int rc;
+
+       if (!gen) {
+               WARN_ON(1);
+               return -EINVAL;
+       }
+       rc = sscanf(str, "0x%08x", gen);
+       if (rc != 1) {
+               pr_err("failed to parse PR gen: %s\n", str);
+               return -EINVAL;
+       }
+
+       pr_debug("processed pr_info generation: %s\n", str);
+
+       return 0;
+}
+
+static int
+tcmu_pr_info_gen_encode(char *buf, size_t buf_remain, u32 gen)
+{
+       int rc;
+
+       rc = snprintf(buf, buf_remain, "0x%08x\n", gen);
+       if ((rc < 0) || (rc >= buf_remain)) {
+               pr_err("failed to encode PR gen\n");
+               return -EINVAL;
+       }
+
+       return rc;
+}
+
 static int tcmu_configure_device(struct se_device *dev)
 {
        struct tcmu_dev *udev = TCMU_DEV(dev);
-- 
2.17.1