target: Fix R_HOLDER bit usage for AllRegistrants

This patch fixes the usage of R_HOLDER bit for an All Registrants
reservation in READ_FULL_STATUS, where only the registration who
issued RESERVE was being reported as having an active reservation.

It changes core_scsi3_pri_read_full_status() to check ahead of the
list walk of active registrations to see if All Registrants is active,
and if so set R_HOLDER bit and scope/type fields for all active
registrations.

Reported-by: Ilias Tsitsimpis <i.tsitsimpis@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index f91b6a1b846eee59a2ddbcf42e88189ea4795d4e..c4a8da5415c557bbf6f2c9899150a297bd9ff3f0 100644 (file)
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -3834,7 +3834,8 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd)
        unsigned char *buf;
        u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
        u32 off = 8; /* off into first Full Status descriptor */
-       int format_code = 0;
+       int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
+       bool all_reg = false;
 
        if (cmd->data_length < 8) {
                pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
@@ -3851,6 +3852,19 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd)
        buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
        buf[3] = (dev->t10_pr.pr_generation & 0xff);
 
+       spin_lock(&dev->dev_reservation_lock);
+       if (dev->dev_pr_res_holder) {
+               struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
+
+               if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
+                   pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
+                       all_reg = true;
+                       pr_res_type = pr_holder->pr_res_type;
+                       pr_res_scope = pr_holder->pr_res_scope;
+               }
+       }
+       spin_unlock(&dev->dev_reservation_lock);
+
        spin_lock(&pr_tmpl->registration_lock);
        list_for_each_entry_safe(pr_reg, pr_reg_tmp,
                        &pr_tmpl->registration_list, pr_reg_list) {
@@ -3898,14 +3912,20 @@ core_scsi3_pri_read_full_status(struct se_cmd *cmd)
                 * reservation holder for PR_HOLDER bit.
                 *
                 * Also, if this registration is the reservation
-                * holder, fill in SCOPE and TYPE in the next byte.
+                * holder or there is an All Registrants reservation
+                * active, fill in SCOPE and TYPE in the next byte.
                 */
                if (pr_reg->pr_res_holder) {
                        buf[off++] |= 0x01;
                        buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
                                     (pr_reg->pr_res_type & 0x0f);
-               } else
+               } else if (all_reg) {
+                       buf[off++] |= 0x01;
+                       buf[off++] = (pr_res_scope & 0xf0) |
+                                    (pr_res_type & 0x0f);
+               } else {
                        off += 2;
+               }
 
                off += 4; /* Skip over reserved area */
                /*