This patch added a function tcmu_execute_pr_read_keys() which can help handle Persistent Reservation Read Keys.
Signed-off-by: Zhu Lingshan <[email protected]> --- drivers/target/target_core_user.c | 74 +++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 2fcdfc97ca75..a89c866a755d 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -2846,6 +2846,80 @@ static int tcmu_pr_info_mock_empty(struct tcmu_pr_info **_pr_info) return 0; } +static sense_reason_t +tcmu_execute_pr_read_keys(struct se_cmd *cmd, unsigned char *buf, u32 buf_len) +{ + struct se_device *dev = cmd->se_dev; + struct tcmu_pr_info *pr_info = NULL; + struct tcmu_pr_reg *reg; + u32 add_len = 0, off = 8; + int rc; + struct tcmu_dev *udev = TCMU_DEV(dev); + + udev->pr_info.pr_info_buf = kzalloc(TCMU_PR_INFO_XATTR_MAX_SIZE, + GFP_KERNEL); + if (!udev->pr_info.pr_info_buf) + return TCM_OUT_OF_RESOURCES; + + if (buf_len < 8) { + WARN_ON(1); + kfree(udev->pr_info.pr_info_buf); + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + } + + pr_debug("getting pr_info for buf: %p, %u\n", buf, buf_len); + + rc = tcmu_pr_info_get(udev, &pr_info, NULL, NULL); + if (rc == -ENODATA) { + pr_debug("PR info not present for read, mocking empty\n"); + rc = tcmu_pr_info_mock_empty(&pr_info); + } + if (rc < 0) { + kfree(udev->pr_info.pr_info_buf); + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + } + pr_debug("packing read_keys response buf: %p, %u\n", buf, buf_len); + + buf[0] = ((pr_info->gen >> 24) & 0xff); + buf[1] = ((pr_info->gen >> 16) & 0xff); + buf[2] = ((pr_info->gen >> 8) & 0xff); + buf[3] = (pr_info->gen & 0xff); + + pr_debug("packed gen %u in read_keys response\n", pr_info->gen); + + list_for_each_entry(reg, &pr_info->regs, regs_node) { + /* + * Check for overflow of 8byte PRI READ_KEYS payload and + * next reservation key list descriptor. + */ + if ((add_len + 8) > (buf_len - 8)) + break; + + buf[off++] = ((reg->key >> 56) & 0xff); + buf[off++] = ((reg->key >> 48) & 0xff); + buf[off++] = ((reg->key >> 40) & 0xff); + buf[off++] = ((reg->key >> 32) & 0xff); + buf[off++] = ((reg->key >> 24) & 0xff); + buf[off++] = ((reg->key >> 16) & 0xff); + buf[off++] = ((reg->key >> 8) & 0xff); + buf[off++] = (reg->key & 0xff); + pr_debug("packed key 0x%llx in read_keys response\n", reg->key); + + add_len += 8; + } + + buf[4] = ((add_len >> 24) & 0xff); + buf[5] = ((add_len >> 16) & 0xff); + buf[6] = ((add_len >> 8) & 0xff); + buf[7] = (add_len & 0xff); + + pr_debug("packed len %u in read_keys response\n", add_len); + tcmu_pr_info_free(pr_info); + kfree(udev->pr_info.pr_info_buf); + + return TCM_NO_SENSE; +} + static int tcmu_configure_device(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev); -- 2.17.1
