This patch added a function tcmu_pr_info_get() which can help get Persistent Reservation information from a TCMU device.
Signed-off-by: Zhu Lingshan <[email protected]> --- drivers/target/target_core_user.c | 51 +++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 12f4a5a5c1e1..0f8eeed61c60 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -2253,6 +2253,57 @@ static int tcmu_pr_info_decode(char *pr_xattr, int pr_xattr_len, return rc; } +static int tcmu_pr_info_get(struct tcmu_dev *udev, + struct tcmu_pr_info **_pr_info, + char **_pr_xattr, int *_pr_xattr_len) +{ + int rc; + char *pr_xattr = udev->pr_info.pr_info_buf; + char *dup_xattr = NULL; + int pr_xattr_len = 0; + struct tcmu_pr_info *pr_info = NULL; + + if (!_pr_info) { + WARN_ON(1); + return -EINVAL; + } + + rc = tcmu_get_dev_pr_info(udev, &pr_xattr_len); + + if (rc) { + if (rc != -ENODATA) + pr_err("failed to obtain PR xattr: %d\n", rc); + return rc; + } + + if (_pr_xattr) { + /* dup before decode, which trashes @pr_xattr */ + dup_xattr = kstrdup(pr_xattr, GFP_KERNEL); + if (!dup_xattr) + return -ENOMEM; + } + + rc = tcmu_pr_info_decode(pr_xattr, pr_xattr_len, &pr_info); + if (rc) { + pr_err("failed to decode PR xattr: %d\n", rc); + goto err_dup_xattr_free; + } + + if (_pr_xattr) { + WARN_ON(!_pr_xattr_len); + *_pr_xattr = dup_xattr; + *_pr_xattr_len = pr_xattr_len; + } + + *_pr_info = pr_info; + pr_debug("successfully obtained PR info\n"); + return 0; + +err_dup_xattr_free: + kfree(dup_xattr); + return rc; +} + static int tcmu_configure_device(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev); -- 2.17.1
