ieee1394: sbp2: more checks of status block

 - Add checks for the (very unlikely) cases that the target writes too
   little or too much status data or writes unsolicited status.
 - Indicate that these and similar conditions are unlikely().
 - Check the 'resp' and 'sbp_status' fields for possible failure status.
 - Slightly optimize access macros for the status block bitfields.
 - Unify a few related log messages.

TODO:  Check if 'src'==1, then withhold the respective ORB from reuse
until status for any subsequent ORB was received.  This is an old bug
whose fix requires more complex command queue handling.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

diff --git a/drivers/ieee1394/sbp2.c b/drivers/ieee1394/sbp2.c
index c677690..07030be 100644 (file)
--- a/drivers/ieee1394/sbp2.c
+++ b/drivers/ieee1394/sbp2.c
@@ -1201,11 +1201,8 @@ static int sbp2_query_logins(struct scsi_id_instance_data *scsi_id)
                return -EIO;
        }
 
-       if (STATUS_GET_RESP(scsi_id->status_block.ORB_offset_hi_misc) ||
-           STATUS_GET_DEAD_BIT(scsi_id->status_block.ORB_offset_hi_misc) ||
-           STATUS_GET_SBP_STATUS(scsi_id->status_block.ORB_offset_hi_misc)) {
-
-               SBP2_INFO("Error querying logins to SBP-2 device - timed out");
+       if (STATUS_TEST_RDS(scsi_id->status_block.ORB_offset_hi_misc)) {
+               SBP2_INFO("Error querying logins to SBP-2 device - failed");
                return -EIO;
        }
 
@@ -1298,18 +1295,12 @@ static int sbp2_login_device(struct scsi_id_instance_data *scsi_id)
         * Sanity. Make sure status returned matches login orb.
         */
        if (scsi_id->status_block.ORB_offset_lo != scsi_id->login_orb_dma) {
-               SBP2_ERR("Error logging into SBP-2 device - login timed-out");
+               SBP2_ERR("Error logging into SBP-2 device - timed out");
                return -EIO;
        }
 
-       /*
-        * Check status
-        */
-       if (STATUS_GET_RESP(scsi_id->status_block.ORB_offset_hi_misc) ||
-           STATUS_GET_DEAD_BIT(scsi_id->status_block.ORB_offset_hi_misc) ||
-           STATUS_GET_SBP_STATUS(scsi_id->status_block.ORB_offset_hi_misc)) {
-
-               SBP2_ERR("Error logging into SBP-2 device - login failed");
+       if (STATUS_TEST_RDS(scsi_id->status_block.ORB_offset_hi_misc)) {
+               SBP2_ERR("Error logging into SBP-2 device - failed");
                return -EIO;
        }
 
@@ -1333,9 +1324,7 @@ static int sbp2_login_device(struct scsi_id_instance_data *scsi_id)
        scsi_id->sbp2_command_block_agent_addr &= 0x0000ffffffffffffULL;
 
        SBP2_INFO("Logged into SBP-2 device");
-
        return 0;
-
 }
 
 /*
@@ -1466,25 +1455,17 @@ static int sbp2_reconnect_device(struct scsi_id_instance_data *scsi_id)
         * Sanity. Make sure status returned matches reconnect orb.
         */
        if (scsi_id->status_block.ORB_offset_lo != scsi_id->reconnect_orb_dma) {
-               SBP2_ERR("Error reconnecting to SBP-2 device - reconnect timed-out");
+               SBP2_ERR("Error reconnecting to SBP-2 device - timed out");
                return -EIO;
        }
 
-       /*
-        * Check status
-        */
-       if (STATUS_GET_RESP(scsi_id->status_block.ORB_offset_hi_misc) ||
-           STATUS_GET_DEAD_BIT(scsi_id->status_block.ORB_offset_hi_misc) ||
-           STATUS_GET_SBP_STATUS(scsi_id->status_block.ORB_offset_hi_misc)) {
-
-               SBP2_ERR("Error reconnecting to SBP-2 device - reconnect failed");
+       if (STATUS_TEST_RDS(scsi_id->status_block.ORB_offset_hi_misc)) {
+               SBP2_ERR("Error reconnecting to SBP-2 device - failed");
                return -EIO;
        }
 
        HPSB_DEBUG("Reconnected to SBP-2 device");
-
        return 0;
-
 }
 
 /*
@@ -2115,18 +2096,19 @@ static int sbp2_handle_status_write(struct hpsb_host *host, int nodeid,
 
        sbp2util_packet_dump(data, length, "sbp2 status write by device", (u32)addr);
 
-       if (!host) {
+       if (unlikely(length < 8 || length > sizeof(struct sbp2_status_block))) {
+               SBP2_ERR("Wrong size of status block");
+               return RCODE_ADDRESS_ERROR;
+       }
+       if (unlikely(!host)) {
                SBP2_ERR("host is NULL - this is bad!");
                return RCODE_ADDRESS_ERROR;
        }
-
        hi = hpsb_get_hostinfo(&sbp2_highlevel, host);
-
-       if (!hi) {
+       if (unlikely(!hi)) {
                SBP2_ERR("host info is NULL - this is bad!");
                return RCODE_ADDRESS_ERROR;
        }
-
        /*
         * Find our scsi_id structure by looking at the status fifo address
         * written to by the sbp2 device.
@@ -2138,8 +2120,7 @@ static int sbp2_handle_status_write(struct hpsb_host *host, int nodeid,
                        break;
                }
        }
-
-       if (!scsi_id) {
+       if (unlikely(!scsi_id)) {
                SBP2_ERR("scsi_id is NULL - device is gone?");
                return RCODE_ADDRESS_ERROR;
        }
@@ -2156,12 +2137,14 @@ static int sbp2_handle_status_write(struct hpsb_host *host, int nodeid,
        sbp2util_be32_to_cpu_buffer(sb, 8);
 
        /*
-        * Handle command ORB status here if necessary. First, need to match
-        * status with command.
+        * Ignore unsolicited status. Handle command ORB status.
         */
-       command = sbp2util_find_command_for_orb(scsi_id, sb->ORB_offset_lo);
+       if (unlikely(STATUS_GET_SRC(sb->ORB_offset_hi_misc) == 2))
+               command = NULL;
+       else
+               command = sbp2util_find_command_for_orb(scsi_id,
+                                                       sb->ORB_offset_lo);
        if (command) {
-
                SBP2_DEBUG("Found status for command ORB");
                pci_dma_sync_single_for_cpu(hi->host->pdev, command->command_orb_dma,
                                            sizeof(struct sbp2_command_orb),
@@ -2177,16 +2160,23 @@ static int sbp2_handle_status_write(struct hpsb_host *host, int nodeid,
                 * Matched status with command, now grab scsi command pointers
                 * and check status.
                 */
+               /*
+                * FIXME: If the src field in the status is 1, the ORB DMA must
+                * not be reused until status for a subsequent ORB is received.
+                */
                SCpnt = command->Current_SCpnt;
                spin_lock_irqsave(&scsi_id->sbp2_command_orb_lock, flags);
                sbp2util_mark_command_completed(scsi_id, command);
                spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock, flags);
 
                if (SCpnt) {
+                       if (STATUS_TEST_RS(sb->ORB_offset_hi_misc))
+                               scsi_status =
+                                       SBP2_SCSI_STATUS_COMMAND_TERMINATED;
                        /*
                         * See if the target stored any scsi status information.
                         */
-                       if (STATUS_GET_LENGTH(sb->ORB_offset_hi_misc) > 1) {
+                       if (STATUS_GET_LEN(sb->ORB_offset_hi_misc) > 1) {
                                SBP2_DEBUG("CHECK CONDITION");
                                scsi_status = sbp2_status_to_sense_data(
                                        (unchar *)sb, SCpnt->sense_buffer);
@@ -2196,7 +2186,7 @@ static int sbp2_handle_status_write(struct hpsb_host *host, int nodeid,
                         * Check to see if the dead bit is set. If so, we'll
                         * have to initiate a fetch agent reset.
                         */
-                       if (STATUS_GET_DEAD_BIT(sb->ORB_offset_hi_misc)) {
+                       if (STATUS_TEST_D(sb->ORB_offset_hi_misc)) {
                                SBP2_DEBUG("Dead bit set - "
                                           "initiating fetch agent reset");
                                 sbp2_agent_reset(scsi_id, 0);

diff --git a/drivers/ieee1394/sbp2.h b/drivers/ieee1394/sbp2.h
index b17016b..34e3d37 100644 (file)
--- a/drivers/ieee1394/sbp2.h
+++ b/drivers/ieee1394/sbp2.h
@@ -180,12 +180,14 @@ struct sbp2_unrestricted_page_table {
 
 #define SBP2_SCSI_STATUS_SELECTION_TIMEOUT     0xff
 
-#define STATUS_GET_ORB_OFFSET_HI(value)         (value & 0xffff)
-#define STATUS_GET_SBP_STATUS(value)            ((value >> 16) & 0xff)
-#define STATUS_GET_LENGTH(value)                ((value >> 24) & 0x7)
-#define STATUS_GET_DEAD_BIT(value)              ((value >> 27) & 0x1)
-#define STATUS_GET_RESP(value)                  ((value >> 28) & 0x3)
-#define STATUS_GET_SRC(value)                   ((value >> 30) & 0x3)
+#define STATUS_GET_SRC(value)                  (((value) >> 30) & 0x3)
+#define STATUS_GET_LEN(value)                  (((value) >> 24) & 0x7)
+#define STATUS_GET_ORB_OFFSET_HI(value)                ((value) & 0x0000ffff)
+#define STATUS_TEST_D(value)                   ((value) & 0x08000000)
+/* test 'resp' | 'sbp2_status' */
+#define STATUS_TEST_RS(value)                  ((value) & 0x30ff0000)
+/* test 'resp' | 'dead' | 'sbp2_status' */
+#define STATUS_TEST_RDS(value)                 ((value) & 0x38ff0000)
 
 struct sbp2_status_block {
        u32 ORB_offset_hi_misc;