[Qemu-devel] Fwd: [PATCH v2 3/6] geometry: Add driver methods to probe blocksizes and geometry

[Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>]

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-------- Forwarded Message --------
Subject: [PATCH v2 3/6] geometry: Add driver methods to probe blocksizes 
and geometry
Date: Tue, 18 Nov 2014 17:09:58 +0100
From: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
To: armbru@redhat.com, pbonzini@redhat.com, stefanha@redhat.com, 
kwolf@redhat.com
CC: borntraeger@de.ibm.com, cornelia.huck@de.ibm.com, 
dahi@linux.vnet.ibm.com, mihajlov@linux.vnet.ibm.com, Ekaterina Tumanova 
<tumanova@linux.vnet.ibm.com>

This patch introduces driver methods of defining disk blocksizes
(physical and logical) and hard drive geometry.
The method is only implemented for "host_device". For "raw" devices
driver calls child's method.
The detection will only work for DASD devices. In order to check that
a local CheckForDASD function was introduced, which calls BIODASDINFO2 ioctl
and returns 0 only if it succeeds.

Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
---
  block/raw-posix.c | 65 
+++++++++++++++++++++++++++++++++++++++++++++++++++++++
  block/raw_bsd.c   | 12 ++++++++++
  2 files changed, 77 insertions(+)

diff --git a/block/raw-posix.c b/block/raw-posix.c
index 45f1d79..274ceda 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -56,6 +56,7 @@
  #include <linux/cdrom.h>
  #include <linux/fd.h>
  #include <linux/fs.h>
+#include <linux/hdreg.h>
  #ifndef FS_NOCOW_FL
  #define FS_NOCOW_FL                     0x00800000 /* Do not cow file */
  #endif
@@ -93,6 +94,10 @@
  #include <xfs/xfs.h>
  #endif

+#ifdef __s390__
+#include <asm/dasd.h>
+#endif
+
  //#define DEBUG_FLOPPY

  //#define DEBUG_BLOCK
@@ -678,6 +683,64 @@ static void raw_refresh_limits(BlockDriverState 
*bs, Error **errp)
      bs->bl.opt_mem_alignment = s->buf_align;
  }

+static int CheckForDASD(int fd)
+{
+#ifdef BIODASDINFO2
+    struct dasd_information2_t info = {0};
+
+    return ioctl(fd, BIODASDINFO2, &info);
+#endif
+    return -1;
+}
+
+static struct ProbeBlockSize hdev_probe_blocksizes(BlockDriverState *bs)
+{
+    BDRVRawState *s = bs->opaque;
+    struct ProbeBlockSize block_sizes = {0};
+
+    block_sizes.rc = CheckForDASD(s->fd);
+    /* If DASD, get blocksizes */
+    if (block_sizes.rc == 0) {
+        block_sizes.size.log = probe_logical_blocksize(bs, s->fd);
+        block_sizes.size.phys = probe_physical_blocksize(bs, s->fd);
+    }
+
+    return block_sizes;
+}
+
+static struct ProbeGeometry hdev_probe_geometry(BlockDriverState *bs)
+{
+    BDRVRawState *s = bs->opaque;
+    struct ProbeGeometry geometry = {0};
+    struct hd_geometry ioctl_geo = {0};
+
+    geometry.rc = CheckForDASD(s->fd);
+    if (geometry.rc != 0) {
+        goto done;
+    }
+    /* If DASD, get it's geometry */
+    geometry.rc = ioctl(s->fd, HDIO_GETGEO, &ioctl_geo);
+    /* Do not return a geometry for partition */
+    if (ioctl_geo.start != 0) {
+        geometry.rc = -1;
+        goto done;
+    }
+    /* HDIO_GETGEO may return success even though geo contains zeros
+       (e.g. certain multipath setups) */
+    if (!ioctl_geo.heads || !ioctl_geo.sectors || !ioctl_geo.cylinders) {
+        geometry.rc = -1;
+        goto done;
+    }
+    if (geometry.rc == 0) {
+        geometry.geo.heads = (uint32_t)ioctl_geo.heads;
+        geometry.geo.sectors = (uint32_t)ioctl_geo.sectors;
+        geometry.geo.cylinders = (uint32_t)ioctl_geo.cylinders;
+        geometry.geo.start = (uint32_t)ioctl_geo.start;
+    }
+done:
+   return geometry;
+}
+
  static ssize_t handle_aiocb_ioctl(RawPosixAIOData *aiocb)
  {
      int ret;
@@ -2128,6 +2191,8 @@ static BlockDriver bdrv_host_device = {
      .bdrv_get_info = raw_get_info,
      .bdrv_get_allocated_file_size
                          = raw_get_allocated_file_size,
+    .bdrv_probe_blocksizes = hdev_probe_blocksizes,
+    .bdrv_probe_geometry = hdev_probe_geometry,

      .bdrv_detach_aio_context = raw_detach_aio_context,
      .bdrv_attach_aio_context = raw_attach_aio_context,
diff --git a/block/raw_bsd.c b/block/raw_bsd.c
index 401b967..d164eba 100644
--- a/block/raw_bsd.c
+++ b/block/raw_bsd.c
@@ -173,6 +173,16 @@ static int raw_probe(const uint8_t *buf, int 
buf_size, const char *filename)
      return 1;
  }

+static struct ProbeBlockSize raw_probe_blocksizes(BlockDriverState *bs)
+{
+    return bdrv_probe_blocksizes(bs->file);
+}
+
+static struct ProbeGeometry raw_probe_geometry(BlockDriverState *bs)
+{
+    return bdrv_probe_geometry(bs->file);
+}
+
  static BlockDriver bdrv_raw = {
      .format_name          = "raw",
      .bdrv_probe           = &raw_probe,
@@ -190,6 +200,8 @@ static BlockDriver bdrv_raw = {
      .has_variable_length  = true,
      .bdrv_get_info        = &raw_get_info,
      .bdrv_refresh_limits  = &raw_refresh_limits,
+    .bdrv_probe_blocksizes = &raw_probe_blocksizes,
+    .bdrv_probe_geometry  = &raw_probe_geometry,
      .bdrv_is_inserted     = &raw_is_inserted,
      .bdrv_media_changed   = &raw_media_changed,
      .bdrv_eject           = &raw_eject,
-- 
1.8.5.5