[SCSI] scsi_debug version 1.80

See http://www.torque.net/sg/sdebug26.html for more
information on the scsi_debug driver.

ChangeLog:
  - add 'vpd_use_hostno' parameter to allow simulated hosts
    to see the same set of targets (and luns). For testing
    multipath software.
  - add 'fake_rw' parameter to ignore the data in READ and
    WRITE commands
  - add support for log subpages (new in SPC-4)
  - yield appropriate block descriptor for MODE SENSE
    commands (only for pdt=0 (i.e. disks))
  - REQUEST SENSE response no longer shows the stopped
    power condition (SAT changed to agree with SPC-3)

Signed-off-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 189 insertions, 41 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index a80303c6b3fd..9c0f35820e3e 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -1,5 +1,4 @@
 /*
- *  linux/kernel/scsi_debug.c
  * vvvvvvvvvvvvvvvvvvvvvvv Original vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
  *  Copyright (C) 1992  Eric Youngdale
  *  Simulate a host adapter with 2 disks attached.  Do a lot of checking
@@ -8,7 +7,9 @@
  * ^^^^^^^^^^^^^^^^^^^^^^^ Original ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  *
  *  This version is more generic, simulating a variable number of disk
- *  (or disk like devices) sharing a common amount of RAM
+ *  (or disk like devices) sharing a common amount of RAM. To be more
+ *  realistic, the simulated devices have the transport attributes of
+ *  SAS disks.
  *
  *
  *  For documentation see http://www.torque.net/sg/sdebug26.html
@@ -50,8 +51,8 @@
 #include "scsi_logging.h"
 #include "scsi_debug.h"
 
-#define SCSI_DEBUG_VERSION "1.79"
-static const char * scsi_debug_version_date = "20060604";
+#define SCSI_DEBUG_VERSION "1.80"
+static const char * scsi_debug_version_date = "20060914";
 
 /* Additional Sense Code (ASC) used */
 #define NO_ADDITIONAL_SENSE 0x0
@@ -86,6 +87,8 @@ static const char * scsi_debug_version_date = "20060604";
 #define DEF_D_SENSE   0
 #define DEF_NO_LUN_0   0
 #define DEF_VIRTUAL_GB   0
+#define DEF_FAKE_RW     0
+#define DEF_VPD_USE_HOSTNO 1
 
 /* bit mask values for scsi_debug_opts */
 #define SCSI_DEBUG_OPT_NOISE   1
@@ -127,6 +130,8 @@ static int scsi_debug_ptype = DEF_PTYPE; /* SCSI peripheral type (0==disk) */
 static int scsi_debug_dsense = DEF_D_SENSE;
 static int scsi_debug_no_lun_0 = DEF_NO_LUN_0;
 static int scsi_debug_virtual_gb = DEF_VIRTUAL_GB;
+static int scsi_debug_fake_rw = DEF_FAKE_RW;
+static int scsi_debug_vpd_use_hostno = DEF_VPD_USE_HOSTNO;
 
 static int scsi_debug_cmnd_count = 0;
 
@@ -423,6 +428,8 @@ int scsi_debug_queuecommand(struct scsi_cmnd * SCpnt, done_funct_t done)
         case READ_6:
                 if ((errsts = check_readiness(SCpnt, 0, devip)))
                         break;
+                if (scsi_debug_fake_rw)
+                        break;
                 if ((*cmd) == READ_16) {
                         for (lba = 0, j = 0; j < 8; ++j) {
                                 if (j > 0)
@@ -465,6 +472,8 @@ int scsi_debug_queuecommand(struct scsi_cmnd * SCpnt, done_funct_t done)
         case WRITE_6:
                 if ((errsts = check_readiness(SCpnt, 0, devip)))
                         break;
+                if (scsi_debug_fake_rw)
+                        break;
                 if ((*cmd) == WRITE_16) {
                         for (lba = 0, j = 0; j < 8; ++j) {
                                 if (j > 0)
@@ -941,6 +950,8 @@ static int resp_inquiry(struct scsi_cmnd * scp, int target,
                 char lu_id_str[6];
                 int host_no = devip->sdbg_host->shost->host_no;
                 
+                if (0 == scsi_debug_vpd_use_hostno)
+                        host_no = 0;
                 lu_id_num = devip->wlun ? -1 : (((host_no + 1) * 2000) +
                             (devip->target * 1000) + devip->lun);
                 target_dev_id = ((host_no + 1) * 2000) +
@@ -1059,19 +1070,6 @@ static int resp_requests(struct scsi_cmnd * scp,
                         arr[12] = THRESHOLD_EXCEEDED;
                         arr[13] = 0xff;         /* TEST set and MRIE==6 */
                 }
-        } else if (devip->stopped) {
-                if (want_dsense) {
-                        arr[0] = 0x72;
-                        arr[1] = 0x0;           /* NO_SENSE in sense_key */
-                        arr[2] = LOW_POWER_COND_ON;
-                        arr[3] = 0x0;           /* TEST set and MRIE==6 */
-                } else {
-                        arr[0] = 0x70;
-                        arr[2] = 0x0;           /* NO_SENSE in sense_key */
-                        arr[7] = 0xa;           /* 18 byte sense buffer */
-                        arr[12] = LOW_POWER_COND_ON;
-                        arr[13] = 0x0;          /* TEST set and MRIE==6 */
-                }
         } else {
                 memcpy(arr, sbuff, SDEBUG_SENSE_LEN);
                 if ((cmd[1] & 1) && (! scsi_debug_dsense)) {
@@ -1325,21 +1323,26 @@ static int resp_sas_sha_m_spg(unsigned char * p, int pcontrol)
 static int resp_mode_sense(struct scsi_cmnd * scp, int target,
                            struct sdebug_dev_info * devip)
 {
-        unsigned char dbd;
-        int pcontrol, pcode, subpcode;
+        unsigned char dbd, llbaa;
+        int pcontrol, pcode, subpcode, bd_len;
         unsigned char dev_spec;
-        int alloc_len, msense_6, offset, len, errsts, target_dev_id;
+        int k, alloc_len, msense_6, offset, len, errsts, target_dev_id;
         unsigned char * ap;
         unsigned char arr[SDEBUG_MAX_MSENSE_SZ];
         unsigned char *cmd = (unsigned char *)scp->cmnd;
 
         if ((errsts = check_readiness(scp, 1, devip)))
                 return errsts;
-        dbd = cmd[1] & 0x8;
+        dbd = !!(cmd[1] & 0x8);
         pcontrol = (cmd[2] & 0xc0) >> 6;
         pcode = cmd[2] & 0x3f;
         subpcode = cmd[3];
         msense_6 = (MODE_SENSE == cmd[0]);
+        llbaa = msense_6 ? 0 : !!(cmd[1] & 0x10);
+        if ((0 == scsi_debug_ptype) && (0 == dbd))
+                bd_len = llbaa ? 16 : 8;
+        else
+                bd_len = 0;
         alloc_len = msense_6 ? cmd[4] : ((cmd[7] << 8) | cmd[8]);
         memset(arr, 0, SDEBUG_MAX_MSENSE_SZ);
         if (0x3 == pcontrol) {  /* Saving values not supported */
@@ -1349,15 +1352,58 @@ static int resp_mode_sense(struct scsi_cmnd * scp, int target,
         }
         target_dev_id = ((devip->sdbg_host->shost->host_no + 1) * 2000) +
                         (devip->target * 1000) - 3;
-        dev_spec = DEV_READONLY(target) ? 0x80 : 0x0;
+        /* set DPOFUA bit for disks */
+        if (0 == scsi_debug_ptype)
+                dev_spec = (DEV_READONLY(target) ? 0x80 : 0x0) | 0x10;
+        else
+                dev_spec = 0x0;
         if (msense_6) {
                 arr[2] = dev_spec;
+                arr[3] = bd_len;
                 offset = 4;
         } else {
                 arr[3] = dev_spec;
+                if (16 == bd_len)
+                        arr[4] = 0x1;   /* set LONGLBA bit */
+                arr[7] = bd_len;        /* assume 255 or less */
                 offset = 8;
         }
         ap = arr + offset;
+        if ((bd_len > 0) && (0 == sdebug_capacity)) {
+                if (scsi_debug_virtual_gb > 0) {
+                        sdebug_capacity = 2048 * 1024;
+                        sdebug_capacity *= scsi_debug_virtual_gb;
+                } else
+                        sdebug_capacity = sdebug_store_sectors;
+        }
+        if (8 == bd_len) {
+                if (sdebug_capacity > 0xfffffffe) {
+                        ap[0] = 0xff;
+                        ap[1] = 0xff;
+                        ap[2] = 0xff;
+                        ap[3] = 0xff;
+                } else {
+                        ap[0] = (sdebug_capacity >> 24) & 0xff;
+                        ap[1] = (sdebug_capacity >> 16) & 0xff;
+                        ap[2] = (sdebug_capacity >> 8) & 0xff;
+                        ap[3] = sdebug_capacity & 0xff;
+                }
+                ap[6] = (SECT_SIZE_PER(target) >> 8) & 0xff;
+                ap[7] = SECT_SIZE_PER(target) & 0xff;
+                offset += bd_len;
+                ap = arr + offset;
+        } else if (16 == bd_len) {
+                unsigned long long capac = sdebug_capacity;
+
+                for (k = 0; k < 8; ++k, capac >>= 8)
+                        ap[7 - k] = capac & 0xff;
+                ap[12] = (SECT_SIZE_PER(target) >> 24) & 0xff;
+                ap[13] = (SECT_SIZE_PER(target) >> 16) & 0xff;
+                ap[14] = (SECT_SIZE_PER(target) >> 8) & 0xff;
+                ap[15] = SECT_SIZE_PER(target) & 0xff;
+                offset += bd_len;
+                ap = arr + offset;
+        }
 
         if ((subpcode > 0x0) && (subpcode < 0xff) && (0x19 != pcode)) {
                 /* TODO: Control Extension page */
@@ -1471,7 +1517,7 @@ static int resp_mode_select(struct scsi_cmnd * scp, int mselect6,
                        " IO sent=%d bytes\n", param_len, res);
         md_len = mselect6 ? (arr[0] + 1) : ((arr[0] << 8) + arr[1] + 2);
         bd_len = mselect6 ? arr[3] : ((arr[6] << 8) + arr[7]);
-        if ((md_len > 2) || (0 != bd_len)) {
+        if (md_len > 2) {
                 mk_sense_buffer(devip, ILLEGAL_REQUEST,
                                 INVALID_FIELD_IN_PARAM_LIST, 0);
                 return check_condition_result;
@@ -1544,7 +1590,7 @@ static int resp_ie_l_pg(unsigned char * arr)
 static int resp_log_sense(struct scsi_cmnd * scp,
                           struct sdebug_dev_info * devip)
 {
-        int ppc, sp, pcontrol, pcode, alloc_len, errsts, len, n;
+        int ppc, sp, pcontrol, pcode, subpcode, alloc_len, errsts, len, n;
         unsigned char arr[SDEBUG_MAX_LSENSE_SZ];
         unsigned char *cmd = (unsigned char *)scp->cmnd;
 
@@ -1560,23 +1606,63 @@ static int resp_log_sense(struct scsi_cmnd * scp,
         }
         pcontrol = (cmd[2] & 0xc0) >> 6;
         pcode = cmd[2] & 0x3f;
+        subpcode = cmd[3] & 0xff;
         alloc_len = (cmd[7] << 8) + cmd[8];
         arr[0] = pcode;
-        switch (pcode) {
-        case 0x0:       /* Supported log pages log page */
-                n = 4;
-                arr[n++] = 0x0;         /* this page */
-                arr[n++] = 0xd;         /* Temperature */
-                arr[n++] = 0x2f;        /* Informational exceptions */
-                arr[3] = n - 4;
-                break;
-        case 0xd:       /* Temperature log page */
-                arr[3] = resp_temp_l_pg(arr + 4);
-                break;
-        case 0x2f:      /* Informational exceptions log page */
-                arr[3] = resp_ie_l_pg(arr + 4);
-                break;
-        default:
+        if (0 == subpcode) {
+                switch (pcode) {
+                case 0x0:       /* Supported log pages log page */
+                        n = 4;
+                        arr[n++] = 0x0;         /* this page */
+                        arr[n++] = 0xd;         /* Temperature */
+                        arr[n++] = 0x2f;        /* Informational exceptions */
+                        arr[3] = n - 4;
+                        break;
+                case 0xd:       /* Temperature log page */
+                        arr[3] = resp_temp_l_pg(arr + 4);
+                        break;
+                case 0x2f:      /* Informational exceptions log page */
+                        arr[3] = resp_ie_l_pg(arr + 4);
+                        break;
+                default:
+                        mk_sense_buffer(devip, ILLEGAL_REQUEST,
+                                        INVALID_FIELD_IN_CDB, 0);
+                        return check_condition_result;
+                }
+        } else if (0xff == subpcode) {
+                arr[0] |= 0x40;
+                arr[1] = subpcode;
+                switch (pcode) {
+                case 0x0:       /* Supported log pages and subpages log page */
+                        n = 4;
+                        arr[n++] = 0x0;
+                        arr[n++] = 0x0;         /* 0,0 page */
+                        arr[n++] = 0x0;
+                        arr[n++] = 0xff;        /* this page */
+                        arr[n++] = 0xd;
+                        arr[n++] = 0x0;         /* Temperature */
+                        arr[n++] = 0x2f;
+                        arr[n++] = 0x0; /* Informational exceptions */
+                        arr[3] = n - 4;
+                        break;
+                case 0xd:       /* Temperature subpages */
+                        n = 4;
+                        arr[n++] = 0xd;
+                        arr[n++] = 0x0;         /* Temperature */
+                        arr[3] = n - 4;
+                        break;
+                case 0x2f:      /* Informational exceptions subpages */
+                        n = 4;
+                        arr[n++] = 0x2f;
+                        arr[n++] = 0x0;         /* Informational exceptions */
+                        arr[3] = n - 4;
+                        break;
+                default:
+                        mk_sense_buffer(devip, ILLEGAL_REQUEST,
+                                        INVALID_FIELD_IN_CDB, 0);
+                        return check_condition_result;
+                }
+        } else {
                 mk_sense_buffer(devip, ILLEGAL_REQUEST,
                                 INVALID_FIELD_IN_CDB, 0);
                 return check_condition_result;
@@ -2151,11 +2237,18 @@ static int schedule_resp(struct scsi_cmnd * cmnd,
         }
 }
 
+/* Note: The following macros create attribute files in the
+   /sys/module/scsi_debug/parameters directory. Unfortunately this
+   driver is unaware of a change and cannot trigger auxiliary actions
+   as it can when the corresponding attribute in the
+   /sys/bus/pseudo/drivers/scsi_debug directory is changed.
+ */
 module_param_named(add_host, scsi_debug_add_host, int, S_IRUGO | S_IWUSR);
 module_param_named(delay, scsi_debug_delay, int, S_IRUGO | S_IWUSR);
 module_param_named(dev_size_mb, scsi_debug_dev_size_mb, int, S_IRUGO);
 module_param_named(dsense, scsi_debug_dsense, int, S_IRUGO | S_IWUSR);
 module_param_named(every_nth, scsi_debug_every_nth, int, S_IRUGO | S_IWUSR);
+module_param_named(fake_rw, scsi_debug_fake_rw, int, S_IRUGO | S_IWUSR);
 module_param_named(max_luns, scsi_debug_max_luns, int, S_IRUGO | S_IWUSR);
 module_param_named(no_lun_0, scsi_debug_no_lun_0, int, S_IRUGO | S_IWUSR);
 module_param_named(num_parts, scsi_debug_num_parts, int, S_IRUGO);
@@ -2164,6 +2257,8 @@ module_param_named(opts, scsi_debug_opts, int, S_IRUGO | S_IWUSR);
 module_param_named(ptype, scsi_debug_ptype, int, S_IRUGO | S_IWUSR);
 module_param_named(scsi_level, scsi_debug_scsi_level, int, S_IRUGO);
 module_param_named(virtual_gb, scsi_debug_virtual_gb, int, S_IRUGO | S_IWUSR);
+module_param_named(vpd_use_hostno, scsi_debug_vpd_use_hostno, int,
+                   S_IRUGO | S_IWUSR);
 
 MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
 MODULE_DESCRIPTION("SCSI debug adapter driver");
@@ -2175,6 +2270,7 @@ MODULE_PARM_DESC(delay, "# of jiffies to delay response(def=1)");
 MODULE_PARM_DESC(dev_size_mb, "size in MB of ram shared by devs(def=8)");
 MODULE_PARM_DESC(dsense, "use descriptor sense format(def=0 -> fixed)");
 MODULE_PARM_DESC(every_nth, "timeout every nth command(def=100)");
+MODULE_PARM_DESC(fake_rw, "fake reads/writes instead of copying (def=0)");
 MODULE_PARM_DESC(max_luns, "number of LUNs per target to simulate(def=1)");
 MODULE_PARM_DESC(no_lun_0, "no LU number 0 (def=0 -> have lun 0)");
 MODULE_PARM_DESC(num_parts, "number of partitions(def=0)");
@@ -2183,6 +2279,7 @@ MODULE_PARM_DESC(opts, "1->noise, 2->medium_error, 4->... (def=0)");
 MODULE_PARM_DESC(ptype, "SCSI peripheral type(def=0[disk])");
 MODULE_PARM_DESC(scsi_level, "SCSI level to simulate(def=5[SPC-3])");
 MODULE_PARM_DESC(virtual_gb, "virtual gigabyte size (def=0 -> use dev_size_mb)");
+MODULE_PARM_DESC(vpd_use_hostno, "0 -> dev ids ignore hostno (def=1 -> unique dev ids)");
 
 
 static char sdebug_info[256];
@@ -2334,6 +2431,24 @@ static ssize_t sdebug_dsense_store(struct device_driver * ddp,
 DRIVER_ATTR(dsense, S_IRUGO | S_IWUSR, sdebug_dsense_show,
             sdebug_dsense_store);
 
+static ssize_t sdebug_fake_rw_show(struct device_driver * ddp, char * buf)
+{
+        return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_fake_rw);
+}
+static ssize_t sdebug_fake_rw_store(struct device_driver * ddp,
+                                    const char * buf, size_t count)
+{
+        int n;
+
+        if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+                scsi_debug_fake_rw = n;
+                return count;
+        }
+        return -EINVAL;
+}
+DRIVER_ATTR(fake_rw, S_IRUGO | S_IWUSR, sdebug_fake_rw_show,
+            sdebug_fake_rw_store);
+
 static ssize_t sdebug_no_lun_0_show(struct device_driver * ddp, char * buf)
 {
         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_no_lun_0);
@@ -2487,6 +2602,31 @@ static ssize_t sdebug_add_host_store(struct device_driver * ddp,
 DRIVER_ATTR(add_host, S_IRUGO | S_IWUSR, sdebug_add_host_show, 
             sdebug_add_host_store);
 
+static ssize_t sdebug_vpd_use_hostno_show(struct device_driver * ddp,
+                                          char * buf)
+{
+        return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_vpd_use_hostno);
+}
+static ssize_t sdebug_vpd_use_hostno_store(struct device_driver * ddp,
+                                           const char * buf, size_t count)
+{
+        int n;
+
+        if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+                scsi_debug_vpd_use_hostno = n;
+                return count;
+        }
+        return -EINVAL;
+}
+DRIVER_ATTR(vpd_use_hostno, S_IRUGO | S_IWUSR, sdebug_vpd_use_hostno_show,
+            sdebug_vpd_use_hostno_store);
+
+/* Note: The following function creates attribute files in the
+   /sys/bus/pseudo/drivers/scsi_debug directory. The advantage of these
+   files (over those found in the /sys/module/scsi_debug/parameters
+   directory) is that auxiliary actions can be triggered when an attribute
+   is changed. For example see: sdebug_add_host_store() above.
+ */
 static int do_create_driverfs_files(void)
 {
         int ret;
@@ -2496,23 +2636,31 @@ static int do_create_driverfs_files(void)
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_dev_size_mb);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_dsense);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_every_nth);
+        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_fake_rw);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_max_luns);
-        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_num_tgts);
+        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_no_lun_0);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_num_parts);
+        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_num_tgts);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_ptype);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_opts);
         ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_scsi_level);
+        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_virtual_gb);
+        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_vpd_use_hostno);
         return ret;
 }
 
 static void do_remove_driverfs_files(void)
 {
+        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_vpd_use_hostno);
+        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_virtual_gb);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_scsi_level);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_opts);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_ptype);
-        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_num_parts);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_num_tgts);
+        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_num_parts);
+        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_no_lun_0);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_max_luns);
+        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_fake_rw);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_every_nth);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_dsense);
         driver_remove_file(&sdebug_driverfs_driver, &driver_attr_dev_size_mb);