[SCSI] scsi_debug: Runtime-configurable sector size

Make scsi_debug sector size configurable at load time instead of being
a #define.  Handy for testing 4KB sectors.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 59 insertions, 39 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index f6600bfb5bde..3901125455c9 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -94,6 +94,7 @@ static const char * scsi_debug_version_date = "20070104";
 #define DEF_VIRTUAL_GB   0
 #define DEF_FAKE_RW     0
 #define DEF_VPD_USE_HOSTNO 1
+#define DEF_SECTOR_SIZE 512
 
 /* bit mask values for scsi_debug_opts */
 #define SCSI_DEBUG_OPT_NOISE   1
@@ -142,6 +143,7 @@ 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_sector_size = DEF_SECTOR_SIZE;
 
 static int scsi_debug_cmnd_count = 0;
 
@@ -157,11 +159,6 @@ static int sdebug_heads;		/* heads per disk */
 static int sdebug_cylinders_per;        /* cylinders per surface */
 static int sdebug_sectors_per;          /* sectors per cylinder */
 
-/* default sector size is 512 bytes, 2**9 bytes */
-#define POW2_SECT_SIZE 9
-#define SECT_SIZE (1 << POW2_SECT_SIZE)
-#define SECT_SIZE_PER(TGT) SECT_SIZE
-
 #define SDEBUG_MAX_PARTS 4
 
 #define SDEBUG_SENSE_LEN 32
@@ -878,8 +875,8 @@ static int resp_readcap(struct scsi_cmnd * scp,
                 arr[2] = 0xff;
                 arr[3] = 0xff;
         }
-        arr[6] = (SECT_SIZE_PER(target) >> 8) & 0xff;
-        arr[7] = SECT_SIZE_PER(target) & 0xff;
+        arr[6] = (scsi_debug_sector_size >> 8) & 0xff;
+        arr[7] = scsi_debug_sector_size & 0xff;
         return fill_from_dev_buffer(scp, arr, SDEBUG_READCAP_ARR_SZ);
 }
 
@@ -902,10 +899,10 @@ static int resp_readcap16(struct scsi_cmnd * scp,
         capac = sdebug_capacity - 1;
         for (k = 0; k < 8; ++k, capac >>= 8)
                 arr[7 - k] = capac & 0xff;
-        arr[8] = (SECT_SIZE_PER(target) >> 24) & 0xff;
-        arr[9] = (SECT_SIZE_PER(target) >> 16) & 0xff;
-        arr[10] = (SECT_SIZE_PER(target) >> 8) & 0xff;
-        arr[11] = SECT_SIZE_PER(target) & 0xff;
+        arr[8] = (scsi_debug_sector_size >> 24) & 0xff;
+        arr[9] = (scsi_debug_sector_size >> 16) & 0xff;
+        arr[10] = (scsi_debug_sector_size >> 8) & 0xff;
+        arr[11] = scsi_debug_sector_size & 0xff;
         return fill_from_dev_buffer(scp, arr,
                                     min(alloc_len, SDEBUG_READCAP16_ARR_SZ));
 }
@@ -1019,20 +1016,20 @@ static int resp_disconnect_pg(unsigned char * p, int pcontrol, int target)
 
 static int resp_format_pg(unsigned char * p, int pcontrol, int target)
 {       /* Format device page for mode_sense */
-        unsigned char format_pg[] = {0x3, 0x16, 0, 0, 0, 0, 0, 0,
-                                     0, 0, 0, 0, 0, 0, 0, 0,
-                                     0, 0, 0, 0, 0x40, 0, 0, 0};
-
-        memcpy(p, format_pg, sizeof(format_pg));
-        p[10] = (sdebug_sectors_per >> 8) & 0xff;
-        p[11] = sdebug_sectors_per & 0xff;
-        p[12] = (SECT_SIZE >> 8) & 0xff;
-        p[13] = SECT_SIZE & 0xff;
-        if (DEV_REMOVEABLE(target))
-                p[20] |= 0x20; /* should agree with INQUIRY */
-        if (1 == pcontrol)
-                memset(p + 2, 0, sizeof(format_pg) - 2);
-        return sizeof(format_pg);
+        unsigned char format_pg[] = {0x3, 0x16, 0, 0, 0, 0, 0, 0,
+                                     0, 0, 0, 0, 0, 0, 0, 0,
+                                     0, 0, 0, 0, 0x40, 0, 0, 0};
+
+        memcpy(p, format_pg, sizeof(format_pg));
+        p[10] = (sdebug_sectors_per >> 8) & 0xff;
+        p[11] = sdebug_sectors_per & 0xff;
+        p[12] = (scsi_debug_sector_size >> 8) & 0xff;
+        p[13] = scsi_debug_sector_size & 0xff;
+        if (DEV_REMOVEABLE(target))
+                p[20] |= 0x20; /* should agree with INQUIRY */
+        if (1 == pcontrol)
+                memset(p + 2, 0, sizeof(format_pg) - 2);
+        return sizeof(format_pg);
 }
 
 static int resp_caching_pg(unsigned char * p, int pcontrol, int target)
@@ -1206,8 +1203,8 @@ static int resp_mode_sense(struct scsi_cmnd * scp, int target,
                         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;
+                ap[6] = (scsi_debug_sector_size >> 8) & 0xff;
+                ap[7] = scsi_debug_sector_size & 0xff;
                 offset += bd_len;
                 ap = arr + offset;
         } else if (16 == bd_len) {
@@ -1215,10 +1212,10 @@ static int resp_mode_sense(struct scsi_cmnd * scp, int target,
 
                 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;
+                ap[12] = (scsi_debug_sector_size >> 24) & 0xff;
+                ap[13] = (scsi_debug_sector_size >> 16) & 0xff;
+                ap[14] = (scsi_debug_sector_size >> 8) & 0xff;
+                ap[15] = scsi_debug_sector_size & 0xff;
                 offset += bd_len;
                 ap = arr + offset;
         }
@@ -1519,10 +1516,10 @@ static int do_device_access(struct scsi_cmnd *scmd,
         if (block + num > sdebug_store_sectors)
                 rest = block + num - sdebug_store_sectors;
 
-        ret = func(scmd, fake_storep + (block * SECT_SIZE),
-                   (num - rest) * SECT_SIZE);
+        ret = func(scmd, fake_storep + (block * scsi_debug_sector_size),
+                   (num - rest) * scsi_debug_sector_size);
         if (!ret && rest)
-                ret = func(scmd, fake_storep, rest * SECT_SIZE);
+                ret = func(scmd, fake_storep, rest * scsi_debug_sector_size);
 
         return ret;
 }
@@ -1575,10 +1572,10 @@ static int resp_write(struct scsi_cmnd *SCpnt, unsigned long long lba,
         write_unlock_irqrestore(&atomic_rw, iflags);
         if (-1 == ret)
                 return (DID_ERROR << 16);
-        else if ((ret < (num * SECT_SIZE)) &&
+        else if ((ret < (num * scsi_debug_sector_size)) &&
                  (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts))
                 printk(KERN_INFO "scsi_debug: write: cdb indicated=%u, "
-                       " IO sent=%d bytes\n", num * SECT_SIZE, ret);
+                       " IO sent=%d bytes\n", num * scsi_debug_sector_size, ret);
         return 0;
 }
 
@@ -2085,6 +2082,7 @@ 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_param_named(sector_size, scsi_debug_sector_size, int, S_IRUGO);
 
 MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
 MODULE_DESCRIPTION("SCSI debug adapter driver");
@@ -2106,6 +2104,7 @@ 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)");
+MODULE_PARM_DESC(sector_size, "hardware sector size in bytes (def=512)");
 
 
 static char sdebug_info[256];
@@ -2158,8 +2157,9 @@ static int scsi_debug_proc_info(struct Scsi_Host *host, char *buffer, char **sta
             scsi_debug_dev_size_mb, scsi_debug_opts, scsi_debug_every_nth,
             scsi_debug_cmnd_count, scsi_debug_delay,
             scsi_debug_max_luns, scsi_debug_scsi_level,
-            SECT_SIZE, sdebug_cylinders_per, sdebug_heads, sdebug_sectors_per,
-            num_aborts, num_dev_resets, num_bus_resets, num_host_resets);
+            scsi_debug_sector_size, sdebug_cylinders_per, sdebug_heads,
+            sdebug_sectors_per, num_aborts, num_dev_resets, num_bus_resets,
+            num_host_resets);
         if (pos < offset) {
                 len = 0;
                 begin = pos;
@@ -2434,6 +2434,12 @@ static ssize_t sdebug_vpd_use_hostno_store(struct device_driver * ddp,
 DRIVER_ATTR(vpd_use_hostno, S_IRUGO | S_IWUSR, sdebug_vpd_use_hostno_show,
             sdebug_vpd_use_hostno_store);
 
+static ssize_t sdebug_sector_size_show(struct device_driver * ddp, char * buf)
+{
+        return scnprintf(buf, PAGE_SIZE, "%u\n", scsi_debug_sector_size);
+}
+DRIVER_ATTR(sector_size, S_IRUGO, sdebug_sector_size_show, NULL);
+
 /* 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
@@ -2459,11 +2465,13 @@ static int do_create_driverfs_files(void)
         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);
+        ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_sector_size);
         return ret;
 }
 
 static void do_remove_driverfs_files(void)
 {
+        driver_remove_file(&sdebug_driverfs_driver, &driver_attr_sector_size);
         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);
@@ -2499,10 +2507,22 @@ static int __init scsi_debug_init(void)
         int k;
         int ret;
 
+        switch (scsi_debug_sector_size) {
+        case  512:
+        case 1024:
+        case 2048:
+        case 4096:
+                break;
+        default:
+                printk(KERN_ERR "scsi_debug_init: invalid sector_size %u\n",
+                       scsi_debug_sector_size);
+                return -EINVAL;
+        }
+
         if (scsi_debug_dev_size_mb < 1)
                 scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
         sz = (unsigned long)scsi_debug_dev_size_mb * 1048576;
-        sdebug_store_sectors = sz / SECT_SIZE;
+        sdebug_store_sectors = sz / scsi_debug_sector_size;
         sdebug_capacity = get_sdebug_capacity();
 
         /* play around with geometry, don't waste too much on track 0 */