From 000e084893985208513864a65695e8fbcbd1162f Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Wed, 16 Nov 2011 13:02:54 +0100
Subject: [PATCH] scsi: get physical chs geometry from mode page 0x04

The mode page is marked as obsolete, but QEMU can provide the information.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 src/blockcmd.c | 32 ++++++++++++++++++++++++++++++++
 src/blockcmd.h | 29 +++++++++++++++++++++++++++++
 2 files changed, 61 insertions(+)

diff --git a/src/blockcmd.c b/src/blockcmd.c
index 30a1736..3476cfc 100644
--- a/src/blockcmd.c
+++ b/src/blockcmd.c
@@ -131,6 +131,23 @@ scsi_init_drive(struct drive_s *drive, const char *s, int *pdt, char **desc)
     dprintf(1, "%s blksize=%d sectors=%d\n"
             , s, drive->blksize, (unsigned)drive->sectors);
 
+    struct cdbres_mode_sense_geom geomdata;
+    ret = cdb_mode_sense_geom(&dop, &geomdata);
+    if (ret == 0) {
+        u32 cylinders;
+        cylinders = geomdata.cyl[0] << 16;
+        cylinders |= geomdata.cyl[1] << 8;
+        cylinders |= geomdata.cyl[2];
+        if (cylinders && geomdata.heads &&
+            drive->sectors <= 0xFFFFFFFFULL &&
+            ((u32)drive->sectors % (geomdata.heads * cylinders) == 0)) {
+            drive->pchs.cylinders = cylinders;
+            drive->pchs.heads = geomdata.heads;
+            drive->pchs.spt = (u32)drive->sectors
+     / (geomdata.heads * cylinders);
+        }
+    }
+
     *desc = znprintf(MAXDESCSIZE, "%s Drive %s %s %s"
                       , s, vendor, product, rev);
     return 0;
@@ -185,6 +202,21 @@ cdb_read_capacity(struct disk_op_s *op, struct cdbres_read_capacity *data)
     return cdb_cmd_data(op, &cmd, sizeof(*data));
 }
 
+// Mode sense, geometry page.
+int
+cdb_mode_sense_geom(struct disk_op_s *op, struct cdbres_mode_sense_geom *data)
+{
+    struct cdb_mode_sense cmd;
+    memset(&cmd, 0, sizeof(cmd));
+    cmd.command = CDB_CMD_MODE_SENSE;
+    cmd.flags = 8; /* DBD */
+    cmd.page = MODE_PAGE_HD_GEOMETRY;
+    cmd.count = htons(sizeof(*data));
+    op->count = 1;
+    op->buf_fl = data;
+    return cdb_cmd_data(op, &cmd, sizeof(*data));
+}
+
 // Read sectors.
 int
 cdb_read(struct disk_op_s *op)
diff --git a/src/blockcmd.h b/src/blockcmd.h
index 13ae991..bace649 100644
--- a/src/blockcmd.h
+++ b/src/blockcmd.h
@@ -71,11 +71,40 @@ struct cdbres_inquiry {
     char rev[4];
 } PACKED;
 
+#define CDB_CMD_MODE_SENSE    0x5A
+#define MODE_PAGE_HD_GEOMETRY 0x04
+
+struct cdb_mode_sense {
+    u8 command;
+    u8 flags;
+    u8 page;
+    u32 reserved_03;
+    u16 count;
+    u8 reserved_09;
+    u8 pad[6];
+} PACKED;
+
+struct cdbres_mode_sense_geom {
+    u8 unused_00[3];
+    u8 read_only;
+    u32 unused_04;
+    u8 page;
+    u8 length;
+    u8 cyl[3];
+    u8 heads;
+    u8 precomp[3];
+    u8 reduced[3];
+    u16 step_rate;
+    u8 landing[3];
+    u16 rpm;
+} PACKED;
+
 // blockcmd.c
 int cdb_get_inquiry(struct disk_op_s *op, struct cdbres_inquiry *data);
 int cdb_get_sense(struct disk_op_s *op, struct cdbres_request_sense *data);
 int cdb_test_unit_ready(struct disk_op_s *op);
 int cdb_read_capacity(struct disk_op_s *op, struct cdbres_read_capacity *data);
+int cdb_mode_sense_geom(struct disk_op_s *op, struct cdbres_mode_sense_geom *data);
 int cdb_inquiry(struct disk_op_s *op, struct cdbres_inquiry *data);
 int cdb_read(struct disk_op_s *op);
 int cdb_write(struct disk_op_s *op);
-- 
2.25.1