Module scst_vdisk autogenerates EVPD INQUERY pages 0x80 and 0x83 from virtual devices
names. For cases if several targets with identical configuration are created, scst_vdisk
has module parameter scst_vdisk_ID to make the INQUERY data different for those targets.
This patch makes this functionality complete by making more scalable and reducing chances
for collisions of the autogenerated data.
Signed-off-by: Vladislav Bolkhovitin <[email protected]>
scst_vdisk.c | 44 +++++++++++++++++++-------------------------
1 file changed, 19 insertions(+), 25 deletions(-)
Index: scst/src/dev_handlers/scst_vdisk.c
===================================================================
--- scst/src/dev_handlers/scst_vdisk.c (revision 643)
+++ scst/src/dev_handlers/scst_vdisk.c (working copy)
@@ -1119,21 +1119,17 @@ out_done:
goto out;
}
-static int vdisk_gen_dev_id_num(struct scst_vdisk_dev *virt_dev)
+static uint64_t vdisk_gen_dev_id_num(struct scst_vdisk_dev *virt_dev)
{
- int dev_id_num, i;
+ unsigned int dev_id_num, i;
- for (dev_id_num = 0, i = 0; i < (int)strlen(virt_dev->name); i++) {
+ for (dev_id_num = 0, i = 0; i < strlen(virt_dev->name); i++) {
unsigned int rv = random_values[(int)(virt_dev->name[i])];
- /*
- * Device name maximum length = 16, do some rotating of the
- * bits.
- */
+ /* Do some rotating of the bits */
dev_id_num ^= ((rv << i) | (rv >> (32 - i)));
}
- dev_id_num += scst_vdisk_ID;
- return dev_id_num;
+ return ((uint64_t)scst_vdisk_ID << 32) | dev_id_num;
}
static void vdisk_exec_inquiry(struct scst_cmd *cmd)
@@ -1183,13 +1179,14 @@ static void vdisk_exec_inquiry(struct sc
buf[1] = 0x80; /* removable */
/* Vital Product */
if (cmd->cdb[1] & EVPD) {
- int dev_id_num, dev_id_len;
- char dev_id_str[6];
+ uint64_t dev_id_num;
+ int dev_id_len;
+ char dev_id_str[17];
dev_id_num = vdisk_gen_dev_id_num(virt_dev);
- dev_id_len = scnprintf(dev_id_str, sizeof(dev_id_str), "%d",
+ dev_id_len = scnprintf(dev_id_str, sizeof(dev_id_str), "%llx",
dev_id_num);
- TRACE_DBG("dev_id num %d, str %s, len %d", dev_id_num,
+ TRACE_DBG("dev_id num %lld, str %s, len %d", dev_id_num,
dev_id_str, dev_id_len);
if (0 == cmd->cdb[2]) {
/* supported vital product data pages */
@@ -1210,21 +1207,19 @@ static void vdisk_exec_inquiry(struct sc
int num = 4;
buf[1] = 0x83;
- /* Two identification descriptors: */
/* T10 vendor identifier field format (faked) */
buf[num + 0] = 0x2; /* ASCII */
- buf[num + 1] = 0x1;
- buf[num + 2] = 0x0;
+ buf[num + 1] = 0x1; /* Vendor ID */
if (virt_dev->blockio)
memcpy(&buf[num + 4], SCST_BIO_VENDOR, 8);
else
memcpy(&buf[num + 4], SCST_FIO_VENDOR, 8);
- memset(&buf[num + 12], ' ', 16);
- i = min(strlen(virt_dev->name), (size_t)16);
- memcpy(&buf[num + 12], virt_dev->name, i);
- memcpy(&buf[num + 28], dev_id_str, dev_id_len);
- buf[num + 3] = 8 + 16 + dev_id_len;
+ i = strlen(virt_dev->name) + 1; /* for ' ' */
+ memset(&buf[num + 12], ' ', i + dev_id_len);
+ memcpy(&buf[num + 12], virt_dev->name, i-1);
+ memcpy(&buf[num + 12 + i], dev_id_str, dev_id_len);
+ buf[num + 3] = 8 + i + dev_id_len;
num += buf[num + 3];
#if 0 /* This isn't required and can be misleading, so let's disable it */
@@ -1287,8 +1282,7 @@ static void vdisk_exec_inquiry(struct sc
* aligned.
*/
memset(&buf[16], ' ', 16);
- len = strlen(virt_dev->name);
- len = len < 16 ? len : 16;
+ len = min(strlen(virt_dev->name), (size_t)16);
memcpy(&buf[16], virt_dev->name, len);
/*
@@ -2955,7 +2949,7 @@ static int vdisk_write_proc(char *buffer
strcpy(virt_dev->name, name);
- scnprintf(virt_dev->usn, sizeof(virt_dev->usn), "%x",
+ scnprintf(virt_dev->usn, sizeof(virt_dev->usn), "%llx",
vdisk_gen_dev_id_num(virt_dev));
TRACE_DBG("usn %s", virt_dev->usn);
@@ -3092,7 +3086,7 @@ static int vcdrom_open(char *p, char *na
strcpy(virt_dev->name, name);
- scnprintf(virt_dev->usn, sizeof(virt_dev->usn), "%x",
+ scnprintf(virt_dev->usn, sizeof(virt_dev->usn), "%llx",
vdisk_gen_dev_id_num(virt_dev));
TRACE_DBG("usn %s", virt_dev->usn);